1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998
3 1999, 2000, 2001 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
36 #if !defined FUNCTION_OK_FOR_SIBCALL
37 #define FUNCTION_OK_FOR_SIBCALL(DECL) 1
40 #if !defined PREFERRED_STACK_BOUNDARY && defined STACK_BOUNDARY
41 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
44 /* Decide whether a function's arguments should be processed
45 from first to last or from last to first.
47 They should if the stack and args grow in opposite directions, but
48 only if we have push insns. */
52 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
53 #define PUSH_ARGS_REVERSED PUSH_ARGS
58 #ifndef PUSH_ARGS_REVERSED
59 #define PUSH_ARGS_REVERSED 0
62 #ifndef STACK_POINTER_OFFSET
63 #define STACK_POINTER_OFFSET 0
66 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
67 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
69 /* Data structure and subroutines used within expand_call. */
73 /* Tree node for this argument. */
75 /* Mode for value; TYPE_MODE unless promoted. */
76 enum machine_mode mode;
77 /* Current RTL value for argument, or 0 if it isn't precomputed. */
79 /* Initially-compute RTL value for argument; only for const functions. */
81 /* Register to pass this argument in, 0 if passed on stack, or an
82 PARALLEL if the arg is to be copied into multiple non-contiguous
85 /* Register to pass this argument in when generating tail call sequence.
86 This is not the same register as for normal calls on machines with
89 /* If REG was promoted from the actual mode of the argument expression,
90 indicates whether the promotion is sign- or zero-extended. */
92 /* Number of registers to use. 0 means put the whole arg in registers.
93 Also 0 if not passed in registers. */
95 /* Non-zero if argument must be passed on stack.
96 Note that some arguments may be passed on the stack
97 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
98 pass_on_stack identifies arguments that *cannot* go in registers. */
100 /* Offset of this argument from beginning of stack-args. */
101 struct args_size offset;
102 /* Similar, but offset to the start of the stack slot. Different from
103 OFFSET if this arg pads downward. */
104 struct args_size slot_offset;
105 /* Size of this argument on the stack, rounded up for any padding it gets,
106 parts of the argument passed in registers do not count.
107 If REG_PARM_STACK_SPACE is defined, then register parms
108 are counted here as well. */
109 struct args_size size;
110 /* Location on the stack at which parameter should be stored. The store
111 has already been done if STACK == VALUE. */
113 /* Location on the stack of the start of this argument slot. This can
114 differ from STACK if this arg pads downward. This location is known
115 to be aligned to FUNCTION_ARG_BOUNDARY. */
117 /* Place that this stack area has been saved, if needed. */
119 /* If an argument's alignment does not permit direct copying into registers,
120 copy in smaller-sized pieces into pseudos. These are stored in a
121 block pointed to by this field. The next field says how many
122 word-sized pseudos we made. */
125 /* The amount that the stack pointer needs to be adjusted to
126 force alignment for the next argument. */
127 struct args_size alignment_pad;
130 /* A vector of one char per byte of stack space. A byte if non-zero if
131 the corresponding stack location has been used.
132 This vector is used to prevent a function call within an argument from
133 clobbering any stack already set up. */
134 static char *stack_usage_map;
136 /* Size of STACK_USAGE_MAP. */
137 static int highest_outgoing_arg_in_use;
139 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
140 stack location's tail call argument has been already stored into the stack.
141 This bitmap is used to prevent sibling call optimization if function tries
142 to use parent's incoming argument slots when they have been already
143 overwritten with tail call arguments. */
144 static sbitmap stored_args_map;
146 /* stack_arg_under_construction is nonzero when an argument may be
147 initialized with a constructor call (including a C function that
148 returns a BLKmode struct) and expand_call must take special action
149 to make sure the object being constructed does not overlap the
150 argument list for the constructor call. */
151 int stack_arg_under_construction;
153 static int calls_function PARAMS ((tree, int));
154 static int calls_function_1 PARAMS ((tree, int));
156 /* Nonzero if this is a call to a `const' function. */
158 /* Nonzero if this is a call to a `volatile' function. */
159 #define ECF_NORETURN 2
160 /* Nonzero if this is a call to malloc or a related function. */
162 /* Nonzero if it is plausible that this is a call to alloca. */
163 #define ECF_MAY_BE_ALLOCA 8
164 /* Nonzero if this is a call to a function that won't throw an exception. */
165 #define ECF_NOTHROW 16
166 /* Nonzero if this is a call to setjmp or a related function. */
167 #define ECF_RETURNS_TWICE 32
168 /* Nonzero if this is a call to `longjmp'. */
169 #define ECF_LONGJMP 64
170 /* Nonzero if this is a syscall that makes a new process in the image of
172 #define ECF_FORK_OR_EXEC 128
173 #define ECF_SIBCALL 256
174 /* Nonzero if this is a call to "pure" function (like const function,
175 but may read memory. */
177 /* Nonzero if this is a call to a function that returns with the stack
178 pointer depressed. */
179 #define ECF_SP_DEPRESSED 1024
181 static void emit_call_1 PARAMS ((rtx, tree, tree, HOST_WIDE_INT,
182 HOST_WIDE_INT, HOST_WIDE_INT, rtx,
183 rtx, int, rtx, int));
184 static void precompute_register_parameters PARAMS ((int,
187 static int store_one_arg PARAMS ((struct arg_data *, rtx, int, int,
189 static void store_unaligned_arguments_into_pseudos PARAMS ((struct arg_data *,
191 static int finalize_must_preallocate PARAMS ((int, int,
193 struct args_size *));
194 static void precompute_arguments PARAMS ((int, int,
196 static int compute_argument_block_size PARAMS ((int,
199 static void initialize_argument_information PARAMS ((int,
206 static void compute_argument_addresses PARAMS ((struct arg_data *,
208 static rtx rtx_for_function_call PARAMS ((tree, tree));
209 static void load_register_parameters PARAMS ((struct arg_data *,
211 static rtx emit_library_call_value_1 PARAMS ((int, rtx, rtx,
215 static int special_function_p PARAMS ((tree, int));
216 static int flags_from_decl_or_type PARAMS ((tree));
217 static rtx try_to_integrate PARAMS ((tree, tree, rtx,
219 static int check_sibcall_argument_overlap_1 PARAMS ((rtx));
220 static int check_sibcall_argument_overlap PARAMS ((rtx, struct arg_data *));
222 static int combine_pending_stack_adjustment_and_call
223 PARAMS ((int, struct args_size *, int));
225 #ifdef REG_PARM_STACK_SPACE
226 static rtx save_fixed_argument_area PARAMS ((int, rtx, int *, int *));
227 static void restore_fixed_argument_area PARAMS ((rtx, rtx, int, int));
230 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
233 If WHICH is 0, return 1 if EXP contains a call to any function.
234 Actually, we only need return 1 if evaluating EXP would require pushing
235 arguments on the stack, but that is too difficult to compute, so we just
236 assume any function call might require the stack. */
238 static tree calls_function_save_exprs;
241 calls_function (exp, which)
247 calls_function_save_exprs = 0;
248 val = calls_function_1 (exp, which);
249 calls_function_save_exprs = 0;
253 /* Recursive function to do the work of above function. */
256 calls_function_1 (exp, which)
261 enum tree_code code = TREE_CODE (exp);
262 int class = TREE_CODE_CLASS (code);
263 int length = first_rtl_op (code);
265 /* If this code is language-specific, we don't know what it will do. */
266 if ((int) code >= NUM_TREE_CODES)
274 else if ((TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))
276 && (TYPE_RETURNS_STACK_DEPRESSED
277 (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))))
279 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
280 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
282 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
284 & ECF_MAY_BE_ALLOCA))
293 for (tem = CONSTRUCTOR_ELTS (exp); tem != 0; tem = TREE_CHAIN (tem))
294 if (calls_function_1 (TREE_VALUE (tem), which))
301 if (SAVE_EXPR_RTL (exp) != 0)
303 if (value_member (exp, calls_function_save_exprs))
305 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
306 calls_function_save_exprs);
307 return (TREE_OPERAND (exp, 0) != 0
308 && calls_function_1 (TREE_OPERAND (exp, 0), which));
313 register tree subblock;
315 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
316 if (DECL_INITIAL (local) != 0
317 && calls_function_1 (DECL_INITIAL (local), which))
320 for (subblock = BLOCK_SUBBLOCKS (exp);
322 subblock = TREE_CHAIN (subblock))
323 if (calls_function_1 (subblock, which))
329 for (; exp != 0; exp = TREE_CHAIN (exp))
330 if (calls_function_1 (TREE_VALUE (exp), which))
338 /* Only expressions, references, and blocks can contain calls. */
339 if (! IS_EXPR_CODE_CLASS (class) && class != 'r' && class != 'b')
342 for (i = 0; i < length; i++)
343 if (TREE_OPERAND (exp, i) != 0
344 && calls_function_1 (TREE_OPERAND (exp, i), which))
350 /* Force FUNEXP into a form suitable for the address of a CALL,
351 and return that as an rtx. Also load the static chain register
352 if FNDECL is a nested function.
354 CALL_FUSAGE points to a variable holding the prospective
355 CALL_INSN_FUNCTION_USAGE information. */
358 prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen, sibcallp)
365 rtx static_chain_value = 0;
367 funexp = protect_from_queue (funexp, 0);
370 /* Get possible static chain value for nested function in C. */
371 static_chain_value = lookup_static_chain (fndecl);
373 /* Make a valid memory address and copy constants thru pseudo-regs,
374 but not for a constant address if -fno-function-cse. */
375 if (GET_CODE (funexp) != SYMBOL_REF)
376 /* If we are using registers for parameters, force the
377 function address into a register now. */
378 funexp = ((SMALL_REGISTER_CLASSES && reg_parm_seen)
379 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
380 : memory_address (FUNCTION_MODE, funexp));
383 #ifndef NO_FUNCTION_CSE
384 if (optimize && ! flag_no_function_cse)
385 #ifdef NO_RECURSIVE_FUNCTION_CSE
386 if (fndecl != current_function_decl)
388 funexp = force_reg (Pmode, funexp);
392 if (static_chain_value != 0)
394 emit_move_insn (static_chain_rtx, static_chain_value);
396 if (GET_CODE (static_chain_rtx) == REG)
397 use_reg (call_fusage, static_chain_rtx);
403 /* Generate instructions to call function FUNEXP,
404 and optionally pop the results.
405 The CALL_INSN is the first insn generated.
407 FNDECL is the declaration node of the function. This is given to the
408 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
410 FUNTYPE is the data type of the function. This is given to the macro
411 RETURN_POPS_ARGS to determine whether this function pops its own args.
412 We used to allow an identifier for library functions, but that doesn't
413 work when the return type is an aggregate type and the calling convention
414 says that the pointer to this aggregate is to be popped by the callee.
416 STACK_SIZE is the number of bytes of arguments on the stack,
417 ROUNDED_STACK_SIZE is that number rounded up to
418 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
419 both to put into the call insn and to generate explicit popping
422 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
423 It is zero if this call doesn't want a structure value.
425 NEXT_ARG_REG is the rtx that results from executing
426 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
427 just after all the args have had their registers assigned.
428 This could be whatever you like, but normally it is the first
429 arg-register beyond those used for args in this call,
430 or 0 if all the arg-registers are used in this call.
431 It is passed on to `gen_call' so you can put this info in the call insn.
433 VALREG is a hard register in which a value is returned,
434 or 0 if the call does not return a value.
436 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
437 the args to this call were processed.
438 We restore `inhibit_defer_pop' to that value.
440 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
441 denote registers used by the called function. */
444 emit_call_1 (funexp, fndecl, funtype, stack_size, rounded_stack_size,
445 struct_value_size, next_arg_reg, valreg, old_inhibit_defer_pop,
446 call_fusage, ecf_flags)
448 tree fndecl ATTRIBUTE_UNUSED;
449 tree funtype ATTRIBUTE_UNUSED;
450 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED;
451 HOST_WIDE_INT rounded_stack_size;
452 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED;
455 int old_inhibit_defer_pop;
459 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
461 int already_popped = 0;
462 HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
463 #if defined (HAVE_call) && defined (HAVE_call_value)
464 rtx struct_value_size_rtx;
465 struct_value_size_rtx = GEN_INT (struct_value_size);
468 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
469 and we don't want to load it into a register as an optimization,
470 because prepare_call_address already did it if it should be done. */
471 if (GET_CODE (funexp) != SYMBOL_REF)
472 funexp = memory_address (FUNCTION_MODE, funexp);
474 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
475 if ((ecf_flags & ECF_SIBCALL)
476 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
477 && (n_popped > 0 || stack_size == 0))
479 rtx n_pop = GEN_INT (n_popped));
482 /* If this subroutine pops its own args, record that in the call insn
483 if possible, for the sake of frame pointer elimination. */
486 pat = GEN_SIBCALL_VALUE_POP (valreg,
487 gen_rtx_MEM (FUNCTION_MODE, funexp),
488 rounded_stack_size_rtx, next_arg_reg,
491 pat = GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
492 rounded_stack_size_rtx, next_arg_reg, n_pop);
494 emit_call_insn (pat);
500 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
501 /* If the target has "call" or "call_value" insns, then prefer them
502 if no arguments are actually popped. If the target does not have
503 "call" or "call_value" insns, then we must use the popping versions
504 even if the call has no arguments to pop. */
505 #if defined (HAVE_call) && defined (HAVE_call_value)
506 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
507 && n_popped > 0 && ! (ecf_flags & ECF_SP_DEPRESSED))
509 if (HAVE_call_pop && HAVE_call_value_pop)
512 rtx n_pop = GEN_INT (n_popped);
515 /* If this subroutine pops its own args, record that in the call insn
516 if possible, for the sake of frame pointer elimination. */
519 pat = GEN_CALL_VALUE_POP (valreg,
520 gen_rtx_MEM (FUNCTION_MODE, funexp),
521 rounded_stack_size_rtx, next_arg_reg, n_pop);
523 pat = GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
524 rounded_stack_size_rtx, next_arg_reg, n_pop);
526 emit_call_insn (pat);
532 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
533 if ((ecf_flags & ECF_SIBCALL)
534 && HAVE_sibcall && HAVE_sibcall_value)
537 emit_call_insn (GEN_SIBCALL_VALUE (valreg,
538 gen_rtx_MEM (FUNCTION_MODE, funexp),
539 rounded_stack_size_rtx,
540 next_arg_reg, NULL_RTX));
542 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
543 rounded_stack_size_rtx, next_arg_reg,
544 struct_value_size_rtx));
549 #if defined (HAVE_call) && defined (HAVE_call_value)
550 if (HAVE_call && HAVE_call_value)
553 emit_call_insn (GEN_CALL_VALUE (valreg,
554 gen_rtx_MEM (FUNCTION_MODE, funexp),
555 rounded_stack_size_rtx, next_arg_reg,
558 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
559 rounded_stack_size_rtx, next_arg_reg,
560 struct_value_size_rtx));
566 /* Find the CALL insn we just emitted. */
567 for (call_insn = get_last_insn ();
568 call_insn && GET_CODE (call_insn) != CALL_INSN;
569 call_insn = PREV_INSN (call_insn))
575 /* Mark memory as used for "pure" function call. */
576 if (ecf_flags & ECF_PURE)
578 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
579 gen_rtx_USE (VOIDmode,
580 gen_rtx_MEM (BLKmode,
581 gen_rtx_SCRATCH (VOIDmode))), call_fusage);
584 /* Put the register usage information on the CALL. If there is already
585 some usage information, put ours at the end. */
586 if (CALL_INSN_FUNCTION_USAGE (call_insn))
590 for (link = CALL_INSN_FUNCTION_USAGE (call_insn); XEXP (link, 1) != 0;
591 link = XEXP (link, 1))
594 XEXP (link, 1) = call_fusage;
597 CALL_INSN_FUNCTION_USAGE (call_insn) = call_fusage;
599 /* If this is a const call, then set the insn's unchanging bit. */
600 if (ecf_flags & (ECF_CONST | ECF_PURE))
601 CONST_CALL_P (call_insn) = 1;
603 /* If this call can't throw, attach a REG_EH_REGION reg note to that
605 if (ecf_flags & ECF_NOTHROW)
606 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_EH_REGION, const0_rtx,
607 REG_NOTES (call_insn));
609 if (ecf_flags & ECF_NORETURN)
610 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_NORETURN, const0_rtx,
611 REG_NOTES (call_insn));
613 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
615 /* Restore this now, so that we do defer pops for this call's args
616 if the context of the call as a whole permits. */
617 inhibit_defer_pop = old_inhibit_defer_pop;
622 CALL_INSN_FUNCTION_USAGE (call_insn)
623 = gen_rtx_EXPR_LIST (VOIDmode,
624 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
625 CALL_INSN_FUNCTION_USAGE (call_insn));
626 rounded_stack_size -= n_popped;
627 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
628 stack_pointer_delta -= n_popped;
631 if (!ACCUMULATE_OUTGOING_ARGS)
633 /* If returning from the subroutine does not automatically pop the args,
634 we need an instruction to pop them sooner or later.
635 Perhaps do it now; perhaps just record how much space to pop later.
637 If returning from the subroutine does pop the args, indicate that the
638 stack pointer will be changed. */
640 if (rounded_stack_size != 0 && ! (ecf_flags & ECF_SP_DEPRESSED))
642 if (flag_defer_pop && inhibit_defer_pop == 0
643 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
644 pending_stack_adjust += rounded_stack_size;
646 adjust_stack (rounded_stack_size_rtx);
649 /* When we accumulate outgoing args, we must avoid any stack manipulations.
650 Restore the stack pointer to its original value now. Usually
651 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
652 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
653 popping variants of functions exist as well.
655 ??? We may optimize similar to defer_pop above, but it is
656 probably not worthwhile.
658 ??? It will be worthwhile to enable combine_stack_adjustments even for
661 anti_adjust_stack (GEN_INT (n_popped));
664 /* Determine if the function identified by NAME and FNDECL is one with
665 special properties we wish to know about.
667 For example, if the function might return more than one time (setjmp), then
668 set RETURNS_TWICE to a nonzero value.
670 Similarly set LONGJMP for if the function is in the longjmp family.
672 Set MALLOC for any of the standard memory allocation functions which
673 allocate from the heap.
675 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
676 space from the stack such as alloca. */
679 special_function_p (fndecl, flags)
683 if (! (flags & ECF_MALLOC)
684 && fndecl && DECL_NAME (fndecl)
685 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
686 /* Exclude functions not at the file scope, or not `extern',
687 since they are not the magic functions we would otherwise
689 && DECL_CONTEXT (fndecl) == NULL_TREE && TREE_PUBLIC (fndecl))
691 const char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
692 const char *tname = name;
694 /* We assume that alloca will always be called by name. It
695 makes no sense to pass it as a pointer-to-function to
696 anything that does not understand its behavior. */
697 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
699 && ! strcmp (name, "alloca"))
700 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
702 && ! strcmp (name, "__builtin_alloca"))))
703 flags |= ECF_MAY_BE_ALLOCA;
705 /* Disregard prefix _, __ or __x. */
708 if (name[1] == '_' && name[2] == 'x')
710 else if (name[1] == '_')
719 && (! strcmp (tname, "setjmp")
720 || ! strcmp (tname, "setjmp_syscall")))
722 && ! strcmp (tname, "sigsetjmp"))
724 && ! strcmp (tname, "savectx")))
725 flags |= ECF_RETURNS_TWICE;
728 && ! strcmp (tname, "siglongjmp"))
729 flags |= ECF_LONGJMP;
731 else if ((tname[0] == 'q' && tname[1] == 's'
732 && ! strcmp (tname, "qsetjmp"))
733 || (tname[0] == 'v' && tname[1] == 'f'
734 && ! strcmp (tname, "vfork")))
735 flags |= ECF_RETURNS_TWICE;
737 else if (tname[0] == 'l' && tname[1] == 'o'
738 && ! strcmp (tname, "longjmp"))
739 flags |= ECF_LONGJMP;
741 else if ((tname[0] == 'f' && tname[1] == 'o'
742 && ! strcmp (tname, "fork"))
743 /* Linux specific: __clone. check NAME to insist on the
744 leading underscores, to avoid polluting the ISO / POSIX
746 || (name[0] == '_' && name[1] == '_'
747 && ! strcmp (tname, "clone"))
748 || (tname[0] == 'e' && tname[1] == 'x' && tname[2] == 'e'
749 && tname[3] == 'c' && (tname[4] == 'l' || tname[4] == 'v')
751 || ((tname[5] == 'p' || tname[5] == 'e')
752 && tname[6] == '\0'))))
753 flags |= ECF_FORK_OR_EXEC;
755 /* Do not add any more malloc-like functions to this list,
756 instead mark them as malloc functions using the malloc attribute.
757 Note, realloc is not suitable for attribute malloc since
758 it may return the same address across multiple calls.
759 C++ operator new is not suitable because it is not required
760 to return a unique pointer; indeed, the standard placement new
761 just returns its argument. */
762 else if (TYPE_MODE (TREE_TYPE (TREE_TYPE (fndecl))) == Pmode
763 && (! strcmp (tname, "malloc")
764 || ! strcmp (tname, "calloc")
765 || ! strcmp (tname, "strdup")))
771 /* Return nonzero when tree represent call to longjmp. */
774 setjmp_call_p (fndecl)
777 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
780 /* Detect flags (function attributes) from the function type node. */
783 flags_from_decl_or_type (exp)
788 /* ??? We can't set IS_MALLOC for function types? */
791 /* The function exp may have the `malloc' attribute. */
792 if (DECL_P (exp) && DECL_IS_MALLOC (exp))
795 /* The function exp may have the `pure' attribute. */
796 if (DECL_P (exp) && DECL_IS_PURE (exp))
799 if (TREE_NOTHROW (exp))
800 flags |= ECF_NOTHROW;
803 if (TREE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
806 if (TREE_THIS_VOLATILE (exp))
807 flags |= ECF_NORETURN;
812 /* Precompute all register parameters as described by ARGS, storing values
813 into fields within the ARGS array.
815 NUM_ACTUALS indicates the total number elements in the ARGS array.
817 Set REG_PARM_SEEN if we encounter a register parameter. */
820 precompute_register_parameters (num_actuals, args, reg_parm_seen)
822 struct arg_data *args;
829 for (i = 0; i < num_actuals; i++)
830 if (args[i].reg != 0 && ! args[i].pass_on_stack)
834 if (args[i].value == 0)
837 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
839 preserve_temp_slots (args[i].value);
842 /* ANSI doesn't require a sequence point here,
843 but PCC has one, so this will avoid some problems. */
847 /* If we are to promote the function arg to a wider mode,
850 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
852 = convert_modes (args[i].mode,
853 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
854 args[i].value, args[i].unsignedp);
856 /* If the value is expensive, and we are inside an appropriately
857 short loop, put the value into a pseudo and then put the pseudo
860 For small register classes, also do this if this call uses
861 register parameters. This is to avoid reload conflicts while
862 loading the parameters registers. */
864 if ((! (GET_CODE (args[i].value) == REG
865 || (GET_CODE (args[i].value) == SUBREG
866 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
867 && args[i].mode != BLKmode
868 && rtx_cost (args[i].value, SET) > COSTS_N_INSNS (1)
869 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
870 || preserve_subexpressions_p ()))
871 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
875 #ifdef REG_PARM_STACK_SPACE
877 /* The argument list is the property of the called routine and it
878 may clobber it. If the fixed area has been used for previous
879 parameters, we must save and restore it. */
882 save_fixed_argument_area (reg_parm_stack_space, argblock,
883 low_to_save, high_to_save)
884 int reg_parm_stack_space;
890 rtx save_area = NULL_RTX;
892 /* Compute the boundary of the that needs to be saved, if any. */
893 #ifdef ARGS_GROW_DOWNWARD
894 for (i = 0; i < reg_parm_stack_space + 1; i++)
896 for (i = 0; i < reg_parm_stack_space; i++)
899 if (i >= highest_outgoing_arg_in_use
900 || stack_usage_map[i] == 0)
903 if (*low_to_save == -1)
909 if (*low_to_save >= 0)
911 int num_to_save = *high_to_save - *low_to_save + 1;
912 enum machine_mode save_mode
913 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
916 /* If we don't have the required alignment, must do this in BLKmode. */
917 if ((*low_to_save & (MIN (GET_MODE_SIZE (save_mode),
918 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
921 #ifdef ARGS_GROW_DOWNWARD
923 = gen_rtx_MEM (save_mode,
924 memory_address (save_mode,
925 plus_constant (argblock,
928 stack_area = gen_rtx_MEM (save_mode,
929 memory_address (save_mode,
930 plus_constant (argblock,
933 if (save_mode == BLKmode)
935 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
936 /* Cannot use emit_block_move here because it can be done by a
937 library call which in turn gets into this place again and deadly
938 infinite recursion happens. */
939 move_by_pieces (validize_mem (save_area), stack_area, num_to_save,
944 save_area = gen_reg_rtx (save_mode);
945 emit_move_insn (save_area, stack_area);
952 restore_fixed_argument_area (save_area, argblock, high_to_save, low_to_save)
958 enum machine_mode save_mode = GET_MODE (save_area);
959 #ifdef ARGS_GROW_DOWNWARD
961 = gen_rtx_MEM (save_mode,
962 memory_address (save_mode,
963 plus_constant (argblock,
967 = gen_rtx_MEM (save_mode,
968 memory_address (save_mode,
969 plus_constant (argblock,
973 if (save_mode != BLKmode)
974 emit_move_insn (stack_area, save_area);
976 /* Cannot use emit_block_move here because it can be done by a library
977 call which in turn gets into this place again and deadly infinite
978 recursion happens. */
979 move_by_pieces (stack_area, validize_mem (save_area),
980 high_to_save - low_to_save + 1, PARM_BOUNDARY);
984 /* If any elements in ARGS refer to parameters that are to be passed in
985 registers, but not in memory, and whose alignment does not permit a
986 direct copy into registers. Copy the values into a group of pseudos
987 which we will later copy into the appropriate hard registers.
989 Pseudos for each unaligned argument will be stored into the array
990 args[argnum].aligned_regs. The caller is responsible for deallocating
991 the aligned_regs array if it is nonzero. */
994 store_unaligned_arguments_into_pseudos (args, num_actuals)
995 struct arg_data *args;
1000 for (i = 0; i < num_actuals; i++)
1001 if (args[i].reg != 0 && ! args[i].pass_on_stack
1002 && args[i].mode == BLKmode
1003 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1004 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1006 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1007 int big_endian_correction = 0;
1009 args[i].n_aligned_regs
1010 = args[i].partial ? args[i].partial
1011 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1013 args[i].aligned_regs = (rtx *) xmalloc (sizeof (rtx)
1014 * args[i].n_aligned_regs);
1016 /* Structures smaller than a word are aligned to the least
1017 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1018 this means we must skip the empty high order bytes when
1019 calculating the bit offset. */
1020 if (BYTES_BIG_ENDIAN && bytes < UNITS_PER_WORD)
1021 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1023 for (j = 0; j < args[i].n_aligned_regs; j++)
1025 rtx reg = gen_reg_rtx (word_mode);
1026 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1027 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1028 int bitalign = TYPE_ALIGN (TREE_TYPE (args[i].tree_value));
1030 args[i].aligned_regs[j] = reg;
1032 /* There is no need to restrict this code to loading items
1033 in TYPE_ALIGN sized hunks. The bitfield instructions can
1034 load up entire word sized registers efficiently.
1036 ??? This may not be needed anymore.
1037 We use to emit a clobber here but that doesn't let later
1038 passes optimize the instructions we emit. By storing 0 into
1039 the register later passes know the first AND to zero out the
1040 bitfield being set in the register is unnecessary. The store
1041 of 0 will be deleted as will at least the first AND. */
1043 emit_move_insn (reg, const0_rtx);
1045 bytes -= bitsize / BITS_PER_UNIT;
1046 store_bit_field (reg, bitsize, big_endian_correction, word_mode,
1047 extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1048 word_mode, word_mode, bitalign,
1050 bitalign, BITS_PER_WORD);
1055 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1058 NUM_ACTUALS is the total number of parameters.
1060 N_NAMED_ARGS is the total number of named arguments.
1062 FNDECL is the tree code for the target of this call (if known)
1064 ARGS_SO_FAR holds state needed by the target to know where to place
1067 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1068 for arguments which are passed in registers.
1070 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1071 and may be modified by this routine.
1073 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1074 flags which may may be modified by this routine. */
1077 initialize_argument_information (num_actuals, args, args_size, n_named_args,
1078 actparms, fndecl, args_so_far,
1079 reg_parm_stack_space, old_stack_level,
1080 old_pending_adj, must_preallocate,
1082 int num_actuals ATTRIBUTE_UNUSED;
1083 struct arg_data *args;
1084 struct args_size *args_size;
1085 int n_named_args ATTRIBUTE_UNUSED;
1088 CUMULATIVE_ARGS *args_so_far;
1089 int reg_parm_stack_space;
1090 rtx *old_stack_level;
1091 int *old_pending_adj;
1092 int *must_preallocate;
1095 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1098 /* Count arg position in order args appear. */
1101 struct args_size alignment_pad;
1105 args_size->constant = 0;
1108 /* In this loop, we consider args in the order they are written.
1109 We fill up ARGS from the front or from the back if necessary
1110 so that in any case the first arg to be pushed ends up at the front. */
1112 if (PUSH_ARGS_REVERSED)
1114 i = num_actuals - 1, inc = -1;
1115 /* In this case, must reverse order of args
1116 so that we compute and push the last arg first. */
1123 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1124 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1126 tree type = TREE_TYPE (TREE_VALUE (p));
1128 enum machine_mode mode;
1130 args[i].tree_value = TREE_VALUE (p);
1132 /* Replace erroneous argument with constant zero. */
1133 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1134 args[i].tree_value = integer_zero_node, type = integer_type_node;
1136 /* If TYPE is a transparent union, pass things the way we would
1137 pass the first field of the union. We have already verified that
1138 the modes are the same. */
1139 if (TREE_CODE (type) == UNION_TYPE && TYPE_TRANSPARENT_UNION (type))
1140 type = TREE_TYPE (TYPE_FIELDS (type));
1142 /* Decide where to pass this arg.
1144 args[i].reg is nonzero if all or part is passed in registers.
1146 args[i].partial is nonzero if part but not all is passed in registers,
1147 and the exact value says how many words are passed in registers.
1149 args[i].pass_on_stack is nonzero if the argument must at least be
1150 computed on the stack. It may then be loaded back into registers
1151 if args[i].reg is nonzero.
1153 These decisions are driven by the FUNCTION_... macros and must agree
1154 with those made by function.c. */
1156 /* See if this argument should be passed by invisible reference. */
1157 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1158 && contains_placeholder_p (TYPE_SIZE (type)))
1159 || TREE_ADDRESSABLE (type)
1160 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1161 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
1162 type, argpos < n_named_args)
1166 /* If we're compiling a thunk, pass through invisible
1167 references instead of making a copy. */
1168 if (current_function_is_thunk
1169 #ifdef FUNCTION_ARG_CALLEE_COPIES
1170 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
1171 type, argpos < n_named_args)
1172 /* If it's in a register, we must make a copy of it too. */
1173 /* ??? Is this a sufficient test? Is there a better one? */
1174 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1175 && REG_P (DECL_RTL (args[i].tree_value)))
1176 && ! TREE_ADDRESSABLE (type))
1180 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1181 new object from the argument. If we are passing by
1182 invisible reference, the callee will do that for us, so we
1183 can strip off the TARGET_EXPR. This is not always safe,
1184 but it is safe in the only case where this is a useful
1185 optimization; namely, when the argument is a plain object.
1186 In that case, the frontend is just asking the backend to
1187 make a bitwise copy of the argument. */
1189 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
1190 && (DECL_P (TREE_OPERAND (args[i].tree_value, 1)))
1191 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
1192 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
1194 args[i].tree_value = build1 (ADDR_EXPR,
1195 build_pointer_type (type),
1196 args[i].tree_value);
1197 type = build_pointer_type (type);
1201 /* We make a copy of the object and pass the address to the
1202 function being called. */
1205 if (!COMPLETE_TYPE_P (type)
1206 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1207 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1208 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1209 STACK_CHECK_MAX_VAR_SIZE))))
1211 /* This is a variable-sized object. Make space on the stack
1213 rtx size_rtx = expr_size (TREE_VALUE (p));
1215 if (*old_stack_level == 0)
1217 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1218 *old_pending_adj = pending_stack_adjust;
1219 pending_stack_adjust = 0;
1222 copy = gen_rtx_MEM (BLKmode,
1223 allocate_dynamic_stack_space
1224 (size_rtx, NULL_RTX, TYPE_ALIGN (type)));
1225 set_mem_attributes (copy, type, 1);
1228 copy = assign_temp (type, 0, 1, 0);
1230 store_expr (args[i].tree_value, copy, 0);
1231 *ecf_flags &= ~(ECF_CONST | ECF_PURE);
1233 args[i].tree_value = build1 (ADDR_EXPR,
1234 build_pointer_type (type),
1235 make_tree (type, copy));
1236 type = build_pointer_type (type);
1240 mode = TYPE_MODE (type);
1241 unsignedp = TREE_UNSIGNED (type);
1243 #ifdef PROMOTE_FUNCTION_ARGS
1244 mode = promote_mode (type, mode, &unsignedp, 1);
1247 args[i].unsignedp = unsignedp;
1248 args[i].mode = mode;
1250 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1251 argpos < n_named_args);
1252 #ifdef FUNCTION_INCOMING_ARG
1253 /* If this is a sibling call and the machine has register windows, the
1254 register window has to be unwinded before calling the routine, so
1255 arguments have to go into the incoming registers. */
1256 args[i].tail_call_reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1257 argpos < n_named_args);
1259 args[i].tail_call_reg = args[i].reg;
1262 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1265 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1266 argpos < n_named_args);
1269 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1271 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1272 it means that we are to pass this arg in the register(s) designated
1273 by the PARALLEL, but also to pass it in the stack. */
1274 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1275 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1276 args[i].pass_on_stack = 1;
1278 /* If this is an addressable type, we must preallocate the stack
1279 since we must evaluate the object into its final location.
1281 If this is to be passed in both registers and the stack, it is simpler
1283 if (TREE_ADDRESSABLE (type)
1284 || (args[i].pass_on_stack && args[i].reg != 0))
1285 *must_preallocate = 1;
1287 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1288 we cannot consider this function call constant. */
1289 if (TREE_ADDRESSABLE (type))
1290 *ecf_flags &= ~(ECF_CONST | ECF_PURE);
1292 /* Compute the stack-size of this argument. */
1293 if (args[i].reg == 0 || args[i].partial != 0
1294 || reg_parm_stack_space > 0
1295 || args[i].pass_on_stack)
1296 locate_and_pad_parm (mode, type,
1297 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1302 fndecl, args_size, &args[i].offset,
1303 &args[i].size, &alignment_pad);
1305 #ifndef ARGS_GROW_DOWNWARD
1306 args[i].slot_offset = *args_size;
1309 args[i].alignment_pad = alignment_pad;
1311 /* If a part of the arg was put into registers,
1312 don't include that part in the amount pushed. */
1313 if (reg_parm_stack_space == 0 && ! args[i].pass_on_stack)
1314 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1315 / (PARM_BOUNDARY / BITS_PER_UNIT)
1316 * (PARM_BOUNDARY / BITS_PER_UNIT));
1318 /* Update ARGS_SIZE, the total stack space for args so far. */
1320 args_size->constant += args[i].size.constant;
1321 if (args[i].size.var)
1323 ADD_PARM_SIZE (*args_size, args[i].size.var);
1326 /* Since the slot offset points to the bottom of the slot,
1327 we must record it after incrementing if the args grow down. */
1328 #ifdef ARGS_GROW_DOWNWARD
1329 args[i].slot_offset = *args_size;
1331 args[i].slot_offset.constant = -args_size->constant;
1333 SUB_PARM_SIZE (args[i].slot_offset, args_size->var);
1336 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1337 have been used, etc. */
1339 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1340 argpos < n_named_args);
1344 /* Update ARGS_SIZE to contain the total size for the argument block.
1345 Return the original constant component of the argument block's size.
1347 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1348 for arguments passed in registers. */
1351 compute_argument_block_size (reg_parm_stack_space, args_size,
1352 preferred_stack_boundary)
1353 int reg_parm_stack_space;
1354 struct args_size *args_size;
1355 int preferred_stack_boundary ATTRIBUTE_UNUSED;
1357 int unadjusted_args_size = args_size->constant;
1359 /* For accumulate outgoing args mode we don't need to align, since the frame
1360 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1361 backends from generating missaligned frame sizes. */
1362 #ifdef STACK_BOUNDARY
1363 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1364 preferred_stack_boundary = STACK_BOUNDARY;
1367 /* Compute the actual size of the argument block required. The variable
1368 and constant sizes must be combined, the size may have to be rounded,
1369 and there may be a minimum required size. */
1373 args_size->var = ARGS_SIZE_TREE (*args_size);
1374 args_size->constant = 0;
1376 #ifdef PREFERRED_STACK_BOUNDARY
1377 preferred_stack_boundary /= BITS_PER_UNIT;
1378 if (preferred_stack_boundary > 1)
1380 /* We don't handle this case yet. To handle it correctly we have
1381 to add the delta, round and substract the delta.
1382 Currently no machine description requires this support. */
1383 if (stack_pointer_delta & (preferred_stack_boundary - 1))
1385 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1389 if (reg_parm_stack_space > 0)
1392 = size_binop (MAX_EXPR, args_size->var,
1393 ssize_int (reg_parm_stack_space));
1395 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1396 /* The area corresponding to register parameters is not to count in
1397 the size of the block we need. So make the adjustment. */
1399 = size_binop (MINUS_EXPR, args_size->var,
1400 ssize_int (reg_parm_stack_space));
1406 #ifdef PREFERRED_STACK_BOUNDARY
1407 preferred_stack_boundary /= BITS_PER_UNIT;
1408 if (preferred_stack_boundary < 1)
1409 preferred_stack_boundary = 1;
1410 args_size->constant = (((args_size->constant
1411 + stack_pointer_delta
1412 + preferred_stack_boundary - 1)
1413 / preferred_stack_boundary
1414 * preferred_stack_boundary)
1415 - stack_pointer_delta);
1418 args_size->constant = MAX (args_size->constant,
1419 reg_parm_stack_space);
1421 #ifdef MAYBE_REG_PARM_STACK_SPACE
1422 if (reg_parm_stack_space == 0)
1423 args_size->constant = 0;
1426 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1427 args_size->constant -= reg_parm_stack_space;
1430 return unadjusted_args_size;
1433 /* Precompute parameters as needed for a function call.
1435 FLAGS is mask of ECF_* constants.
1437 NUM_ACTUALS is the number of arguments.
1439 ARGS is an array containing information for each argument; this
1440 routine fills in the INITIAL_VALUE and VALUE fields for each
1441 precomputed argument. */
1444 precompute_arguments (flags, num_actuals, args)
1447 struct arg_data *args;
1451 /* If this function call is cse'able, precompute all the parameters.
1452 Note that if the parameter is constructed into a temporary, this will
1453 cause an additional copy because the parameter will be constructed
1454 into a temporary location and then copied into the outgoing arguments.
1455 If a parameter contains a call to alloca and this function uses the
1456 stack, precompute the parameter. */
1458 /* If we preallocated the stack space, and some arguments must be passed
1459 on the stack, then we must precompute any parameter which contains a
1460 function call which will store arguments on the stack.
1461 Otherwise, evaluating the parameter may clobber previous parameters
1462 which have already been stored into the stack. (we have code to avoid
1463 such case by saving the ougoing stack arguments, but it results in
1466 for (i = 0; i < num_actuals; i++)
1467 if ((flags & (ECF_CONST | ECF_PURE))
1468 || calls_function (args[i].tree_value, !ACCUMULATE_OUTGOING_ARGS))
1470 enum machine_mode mode;
1472 /* If this is an addressable type, we cannot pre-evaluate it. */
1473 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1479 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1481 preserve_temp_slots (args[i].value);
1484 /* ANSI doesn't require a sequence point here,
1485 but PCC has one, so this will avoid some problems. */
1488 args[i].initial_value = args[i].value
1489 = protect_from_queue (args[i].value, 0);
1491 mode = TYPE_MODE (TREE_TYPE (args[i].tree_value));
1492 if (mode != args[i].mode)
1495 = convert_modes (args[i].mode, mode,
1496 args[i].value, args[i].unsignedp);
1497 #ifdef PROMOTE_FOR_CALL_ONLY
1498 /* CSE will replace this only if it contains args[i].value
1499 pseudo, so convert it down to the declared mode using
1501 if (GET_CODE (args[i].value) == REG
1502 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1504 args[i].initial_value
1505 = gen_lowpart_SUBREG (mode, args[i].value);
1506 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1507 SUBREG_PROMOTED_UNSIGNED_P (args[i].initial_value)
1508 = args[i].unsignedp;
1515 /* Given the current state of MUST_PREALLOCATE and information about
1516 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1517 compute and return the final value for MUST_PREALLOCATE. */
1520 finalize_must_preallocate (must_preallocate, num_actuals, args, args_size)
1521 int must_preallocate;
1523 struct arg_data *args;
1524 struct args_size *args_size;
1526 /* See if we have or want to preallocate stack space.
1528 If we would have to push a partially-in-regs parm
1529 before other stack parms, preallocate stack space instead.
1531 If the size of some parm is not a multiple of the required stack
1532 alignment, we must preallocate.
1534 If the total size of arguments that would otherwise create a copy in
1535 a temporary (such as a CALL) is more than half the total argument list
1536 size, preallocation is faster.
1538 Another reason to preallocate is if we have a machine (like the m88k)
1539 where stack alignment is required to be maintained between every
1540 pair of insns, not just when the call is made. However, we assume here
1541 that such machines either do not have push insns (and hence preallocation
1542 would occur anyway) or the problem is taken care of with
1545 if (! must_preallocate)
1547 int partial_seen = 0;
1548 int copy_to_evaluate_size = 0;
1551 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1553 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1555 else if (partial_seen && args[i].reg == 0)
1556 must_preallocate = 1;
1558 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1559 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1560 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1561 || TREE_CODE (args[i].tree_value) == COND_EXPR
1562 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1563 copy_to_evaluate_size
1564 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1567 if (copy_to_evaluate_size * 2 >= args_size->constant
1568 && args_size->constant > 0)
1569 must_preallocate = 1;
1571 return must_preallocate;
1574 /* If we preallocated stack space, compute the address of each argument
1575 and store it into the ARGS array.
1577 We need not ensure it is a valid memory address here; it will be
1578 validized when it is used.
1580 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1583 compute_argument_addresses (args, argblock, num_actuals)
1584 struct arg_data *args;
1590 rtx arg_reg = argblock;
1591 int i, arg_offset = 0;
1593 if (GET_CODE (argblock) == PLUS)
1594 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1596 for (i = 0; i < num_actuals; i++)
1598 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1599 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1602 /* Skip this parm if it will not be passed on the stack. */
1603 if (! args[i].pass_on_stack && args[i].reg != 0)
1606 if (GET_CODE (offset) == CONST_INT)
1607 addr = plus_constant (arg_reg, INTVAL (offset));
1609 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1611 addr = plus_constant (addr, arg_offset);
1612 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1613 set_mem_attributes (args[i].stack,
1614 TREE_TYPE (args[i].tree_value), 1);
1616 if (GET_CODE (slot_offset) == CONST_INT)
1617 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1619 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1621 addr = plus_constant (addr, arg_offset);
1622 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1623 set_mem_attributes (args[i].stack_slot,
1624 TREE_TYPE (args[i].tree_value), 1);
1626 /* Function incoming arguments may overlap with sibling call
1627 outgoing arguments and we cannot allow reordering of reads
1628 from function arguments with stores to outgoing arguments
1629 of sibling calls. */
1630 set_mem_alias_set (args[i].stack, 0);
1631 set_mem_alias_set (args[i].stack_slot, 0);
1636 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1637 in a call instruction.
1639 FNDECL is the tree node for the target function. For an indirect call
1640 FNDECL will be NULL_TREE.
1642 EXP is the CALL_EXPR for this call. */
1645 rtx_for_function_call (fndecl, exp)
1651 /* Get the function to call, in the form of RTL. */
1654 /* If this is the first use of the function, see if we need to
1655 make an external definition for it. */
1656 if (! TREE_USED (fndecl))
1658 assemble_external (fndecl);
1659 TREE_USED (fndecl) = 1;
1662 /* Get a SYMBOL_REF rtx for the function address. */
1663 funexp = XEXP (DECL_RTL (fndecl), 0);
1666 /* Generate an rtx (probably a pseudo-register) for the address. */
1671 expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1672 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1674 /* Check the function is executable. */
1675 if (current_function_check_memory_usage)
1677 #ifdef POINTERS_EXTEND_UNSIGNED
1678 /* It might be OK to convert funexp in place, but there's
1679 a lot going on between here and when it happens naturally
1680 that this seems safer. */
1681 funaddr = convert_memory_address (Pmode, funexp);
1683 emit_library_call (chkr_check_exec_libfunc, LCT_CONST_MAKE_BLOCK,
1684 VOIDmode, 1, funaddr, Pmode);
1691 /* Do the register loads required for any wholly-register parms or any
1692 parms which are passed both on the stack and in a register. Their
1693 expressions were already evaluated.
1695 Mark all register-parms as living through the call, putting these USE
1696 insns in the CALL_INSN_FUNCTION_USAGE field. */
1699 load_register_parameters (args, num_actuals, call_fusage, flags)
1700 struct arg_data *args;
1707 #ifdef LOAD_ARGS_REVERSED
1708 for (i = num_actuals - 1; i >= 0; i--)
1710 for (i = 0; i < num_actuals; i++)
1713 rtx reg = ((flags & ECF_SIBCALL)
1714 ? args[i].tail_call_reg : args[i].reg);
1715 int partial = args[i].partial;
1720 /* Set to non-negative if must move a word at a time, even if just
1721 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1722 we just use a normal move insn. This value can be zero if the
1723 argument is a zero size structure with no fields. */
1724 nregs = (partial ? partial
1725 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1726 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1727 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1730 /* Handle calls that pass values in multiple non-contiguous
1731 locations. The Irix 6 ABI has examples of this. */
1733 if (GET_CODE (reg) == PARALLEL)
1734 emit_group_load (reg, args[i].value,
1735 int_size_in_bytes (TREE_TYPE (args[i].tree_value)),
1736 TYPE_ALIGN (TREE_TYPE (args[i].tree_value)));
1738 /* If simple case, just do move. If normal partial, store_one_arg
1739 has already loaded the register for us. In all other cases,
1740 load the register(s) from memory. */
1742 else if (nregs == -1)
1743 emit_move_insn (reg, args[i].value);
1745 /* If we have pre-computed the values to put in the registers in
1746 the case of non-aligned structures, copy them in now. */
1748 else if (args[i].n_aligned_regs != 0)
1749 for (j = 0; j < args[i].n_aligned_regs; j++)
1750 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1751 args[i].aligned_regs[j]);
1753 else if (partial == 0 || args[i].pass_on_stack)
1754 move_block_to_reg (REGNO (reg),
1755 validize_mem (args[i].value), nregs,
1758 /* Handle calls that pass values in multiple non-contiguous
1759 locations. The Irix 6 ABI has examples of this. */
1760 if (GET_CODE (reg) == PARALLEL)
1761 use_group_regs (call_fusage, reg);
1762 else if (nregs == -1)
1763 use_reg (call_fusage, reg);
1765 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1770 /* Try to integrate function. See expand_inline_function for documentation
1771 about the parameters. */
1774 try_to_integrate (fndecl, actparms, target, ignore, type, structure_value_addr)
1780 rtx structure_value_addr;
1785 rtx old_stack_level = 0;
1786 int reg_parm_stack_space = 0;
1788 #ifdef REG_PARM_STACK_SPACE
1789 #ifdef MAYBE_REG_PARM_STACK_SPACE
1790 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1792 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1796 before_call = get_last_insn ();
1798 timevar_push (TV_INTEGRATION);
1800 temp = expand_inline_function (fndecl, actparms, target,
1802 structure_value_addr);
1804 timevar_pop (TV_INTEGRATION);
1806 /* If inlining succeeded, return. */
1807 if (temp != (rtx) (HOST_WIDE_INT) - 1)
1809 if (ACCUMULATE_OUTGOING_ARGS)
1811 /* If the outgoing argument list must be preserved, push
1812 the stack before executing the inlined function if it
1815 for (i = reg_parm_stack_space - 1; i >= 0; i--)
1816 if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
1819 if (stack_arg_under_construction || i >= 0)
1822 = before_call ? NEXT_INSN (before_call) : get_insns ();
1823 rtx insn = NULL_RTX, seq;
1825 /* Look for a call in the inline function code.
1826 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1827 nonzero then there is a call and it is not necessary
1828 to scan the insns. */
1830 if (DECL_SAVED_INSNS (fndecl)->outgoing_args_size == 0)
1831 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1832 if (GET_CODE (insn) == CALL_INSN)
1837 /* Reserve enough stack space so that the largest
1838 argument list of any function call in the inline
1839 function does not overlap the argument list being
1840 evaluated. This is usually an overestimate because
1841 allocate_dynamic_stack_space reserves space for an
1842 outgoing argument list in addition to the requested
1843 space, but there is no way to ask for stack space such
1844 that an argument list of a certain length can be
1847 Add the stack space reserved for register arguments, if
1848 any, in the inline function. What is really needed is the
1849 largest value of reg_parm_stack_space in the inline
1850 function, but that is not available. Using the current
1851 value of reg_parm_stack_space is wrong, but gives
1852 correct results on all supported machines. */
1854 int adjust = (DECL_SAVED_INSNS (fndecl)->outgoing_args_size
1855 + reg_parm_stack_space);
1858 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1859 allocate_dynamic_stack_space (GEN_INT (adjust),
1860 NULL_RTX, BITS_PER_UNIT);
1863 emit_insns_before (seq, first_insn);
1864 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1869 /* If the result is equivalent to TARGET, return TARGET to simplify
1870 checks in store_expr. They can be equivalent but not equal in the
1871 case of a function that returns BLKmode. */
1872 if (temp != target && rtx_equal_p (temp, target))
1877 /* If inlining failed, mark FNDECL as needing to be compiled
1878 separately after all. If function was declared inline,
1880 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1881 && optimize > 0 && !TREE_ADDRESSABLE (fndecl))
1883 warning_with_decl (fndecl, "inlining failed in call to `%s'");
1884 warning ("called from here");
1886 mark_addressable (fndecl);
1887 return (rtx) (HOST_WIDE_INT) - 1;
1890 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1891 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1892 bytes, then we would need to push some additional bytes to pad the
1893 arguments. So, we compute an adjust to the stack pointer for an
1894 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1895 bytes. Then, when the arguments are pushed the stack will be perfectly
1896 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1897 be popped after the call. Returns the adjustment. */
1900 combine_pending_stack_adjustment_and_call (unadjusted_args_size,
1902 preferred_unit_stack_boundary)
1903 int unadjusted_args_size;
1904 struct args_size *args_size;
1905 int preferred_unit_stack_boundary;
1907 /* The number of bytes to pop so that the stack will be
1908 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1909 HOST_WIDE_INT adjustment;
1910 /* The alignment of the stack after the arguments are pushed, if we
1911 just pushed the arguments without adjust the stack here. */
1912 HOST_WIDE_INT unadjusted_alignment;
1914 unadjusted_alignment
1915 = ((stack_pointer_delta + unadjusted_args_size)
1916 % preferred_unit_stack_boundary);
1918 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1919 as possible -- leaving just enough left to cancel out the
1920 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1921 PENDING_STACK_ADJUST is non-negative, and congruent to
1922 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1924 /* Begin by trying to pop all the bytes. */
1925 unadjusted_alignment
1926 = (unadjusted_alignment
1927 - (pending_stack_adjust % preferred_unit_stack_boundary));
1928 adjustment = pending_stack_adjust;
1929 /* Push enough additional bytes that the stack will be aligned
1930 after the arguments are pushed. */
1931 if (preferred_unit_stack_boundary > 1)
1933 if (unadjusted_alignment > 0)
1934 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1936 adjustment += unadjusted_alignment;
1939 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1940 bytes after the call. The right number is the entire
1941 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1942 by the arguments in the first place. */
1944 = pending_stack_adjust - adjustment + unadjusted_args_size;
1949 /* Scan X expression if it does not dereference any argument slots
1950 we already clobbered by tail call arguments (as noted in stored_args_map
1952 Return non-zero if X expression dereferences such argument slots,
1956 check_sibcall_argument_overlap_1 (x)
1967 code = GET_CODE (x);
1971 if (XEXP (x, 0) == current_function_internal_arg_pointer)
1973 else if (GET_CODE (XEXP (x, 0)) == PLUS
1974 && XEXP (XEXP (x, 0), 0) ==
1975 current_function_internal_arg_pointer
1976 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
1977 i = INTVAL (XEXP (XEXP (x, 0), 1));
1981 #ifdef ARGS_GROW_DOWNWARD
1982 i = -i - GET_MODE_SIZE (GET_MODE (x));
1985 for (k = 0; k < GET_MODE_SIZE (GET_MODE (x)); k++)
1986 if (i + k < stored_args_map->n_bits
1987 && TEST_BIT (stored_args_map, i + k))
1993 /* Scan all subexpressions. */
1994 fmt = GET_RTX_FORMAT (code);
1995 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
1999 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2002 else if (*fmt == 'E')
2004 for (j = 0; j < XVECLEN (x, i); j++)
2005 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2012 /* Scan sequence after INSN if it does not dereference any argument slots
2013 we already clobbered by tail call arguments (as noted in stored_args_map
2014 bitmap). Add stack slots for ARG to stored_args_map bitmap afterwards.
2015 Return non-zero if sequence after INSN dereferences such argument slots,
2019 check_sibcall_argument_overlap (insn, arg)
2021 struct arg_data *arg;
2025 if (insn == NULL_RTX)
2026 insn = get_insns ();
2028 insn = NEXT_INSN (insn);
2030 for (; insn; insn = NEXT_INSN (insn))
2032 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2035 #ifdef ARGS_GROW_DOWNWARD
2036 low = -arg->offset.constant - arg->size.constant;
2038 low = arg->offset.constant;
2041 for (high = low + arg->size.constant; low < high; low++)
2042 SET_BIT (stored_args_map, low);
2043 return insn != NULL_RTX;
2046 /* Generate all the code for a function call
2047 and return an rtx for its value.
2048 Store the value in TARGET (specified as an rtx) if convenient.
2049 If the value is stored in TARGET then TARGET is returned.
2050 If IGNORE is nonzero, then we ignore the value of the function call. */
2053 expand_call (exp, target, ignore)
2058 /* Nonzero if we are currently expanding a call. */
2059 static int currently_expanding_call = 0;
2061 /* List of actual parameters. */
2062 tree actparms = TREE_OPERAND (exp, 1);
2063 /* RTX for the function to be called. */
2065 /* Sequence of insns to perform a tail recursive "call". */
2066 rtx tail_recursion_insns = NULL_RTX;
2067 /* Sequence of insns to perform a normal "call". */
2068 rtx normal_call_insns = NULL_RTX;
2069 /* Sequence of insns to perform a tail recursive "call". */
2070 rtx tail_call_insns = NULL_RTX;
2071 /* Data type of the function. */
2073 /* Declaration of the function being called,
2074 or 0 if the function is computed (not known by name). */
2077 int try_tail_call = 1;
2078 int try_tail_recursion = 1;
2081 /* Register in which non-BLKmode value will be returned,
2082 or 0 if no value or if value is BLKmode. */
2084 /* Address where we should return a BLKmode value;
2085 0 if value not BLKmode. */
2086 rtx structure_value_addr = 0;
2087 /* Nonzero if that address is being passed by treating it as
2088 an extra, implicit first parameter. Otherwise,
2089 it is passed by being copied directly into struct_value_rtx. */
2090 int structure_value_addr_parm = 0;
2091 /* Size of aggregate value wanted, or zero if none wanted
2092 or if we are using the non-reentrant PCC calling convention
2093 or expecting the value in registers. */
2094 HOST_WIDE_INT struct_value_size = 0;
2095 /* Nonzero if called function returns an aggregate in memory PCC style,
2096 by returning the address of where to find it. */
2097 int pcc_struct_value = 0;
2099 /* Number of actual parameters in this call, including struct value addr. */
2101 /* Number of named args. Args after this are anonymous ones
2102 and they must all go on the stack. */
2105 /* Vector of information about each argument.
2106 Arguments are numbered in the order they will be pushed,
2107 not the order they are written. */
2108 struct arg_data *args;
2110 /* Total size in bytes of all the stack-parms scanned so far. */
2111 struct args_size args_size;
2112 struct args_size adjusted_args_size;
2113 /* Size of arguments before any adjustments (such as rounding). */
2114 int unadjusted_args_size;
2115 /* Data on reg parms scanned so far. */
2116 CUMULATIVE_ARGS args_so_far;
2117 /* Nonzero if a reg parm has been scanned. */
2119 /* Nonzero if this is an indirect function call. */
2121 /* Nonzero if we must avoid push-insns in the args for this call.
2122 If stack space is allocated for register parameters, but not by the
2123 caller, then it is preallocated in the fixed part of the stack frame.
2124 So the entire argument block must then be preallocated (i.e., we
2125 ignore PUSH_ROUNDING in that case). */
2127 int must_preallocate = !PUSH_ARGS;
2129 /* Size of the stack reserved for parameter registers. */
2130 int reg_parm_stack_space = 0;
2132 /* Address of space preallocated for stack parms
2133 (on machines that lack push insns), or 0 if space not preallocated. */
2136 /* Mask of ECF_ flags. */
2138 /* Nonzero if this is a call to an inline function. */
2139 int is_integrable = 0;
2140 #ifdef REG_PARM_STACK_SPACE
2141 /* Define the boundary of the register parm stack space that needs to be
2143 int low_to_save = -1, high_to_save;
2144 rtx save_area = 0; /* Place that it is saved */
2147 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2148 char *initial_stack_usage_map = stack_usage_map;
2149 int old_stack_arg_under_construction = 0;
2151 rtx old_stack_level = 0;
2152 int old_pending_adj = 0;
2153 int old_inhibit_defer_pop = inhibit_defer_pop;
2154 int old_stack_allocated;
2156 register tree p = TREE_OPERAND (exp, 0);
2158 /* The alignment of the stack, in bits. */
2159 HOST_WIDE_INT preferred_stack_boundary;
2160 /* The alignment of the stack, in bytes. */
2161 HOST_WIDE_INT preferred_unit_stack_boundary;
2163 /* The value of the function call can be put in a hard register. But
2164 if -fcheck-memory-usage, code which invokes functions (and thus
2165 damages some hard registers) can be inserted before using the value.
2166 So, target is always a pseudo-register in that case. */
2167 if (current_function_check_memory_usage)
2170 /* See if this is "nothrow" function call. */
2171 if (TREE_NOTHROW (exp))
2172 flags |= ECF_NOTHROW;
2174 /* See if we can find a DECL-node for the actual function.
2175 As a result, decide whether this is a call to an integrable function. */
2177 fndecl = get_callee_fndecl (exp);
2181 && fndecl != current_function_decl
2182 && DECL_INLINE (fndecl)
2183 && DECL_SAVED_INSNS (fndecl)
2184 && DECL_SAVED_INSNS (fndecl)->inlinable)
2186 else if (! TREE_ADDRESSABLE (fndecl))
2188 /* In case this function later becomes inlinable,
2189 record that there was already a non-inline call to it.
2191 Use abstraction instead of setting TREE_ADDRESSABLE
2193 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2196 warning_with_decl (fndecl, "can't inline call to `%s'");
2197 warning ("called from here");
2199 mark_addressable (fndecl);
2202 flags |= flags_from_decl_or_type (fndecl);
2205 /* If we don't have specific function to call, see if we have a
2206 attributes set in the type. */
2208 flags |= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p)));
2210 /* Mark if the function returns with the stack pointer depressed. */
2211 if (TREE_CODE (TREE_TYPE (TREE_TYPE (p))) == FUNCTION_TYPE
2212 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (TREE_TYPE (p))))
2214 flags |= ECF_SP_DEPRESSED;
2215 flags &= ~(ECF_PURE | ECF_CONST);
2218 #ifdef REG_PARM_STACK_SPACE
2219 #ifdef MAYBE_REG_PARM_STACK_SPACE
2220 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
2222 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2226 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2227 if (reg_parm_stack_space > 0 && PUSH_ARGS)
2228 must_preallocate = 1;
2231 /* Warn if this value is an aggregate type,
2232 regardless of which calling convention we are using for it. */
2233 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2234 warning ("function call has aggregate value");
2236 /* Set up a place to return a structure. */
2238 /* Cater to broken compilers. */
2239 if (aggregate_value_p (exp))
2241 /* This call returns a big structure. */
2242 flags &= ~(ECF_CONST | ECF_PURE);
2244 #ifdef PCC_STATIC_STRUCT_RETURN
2246 pcc_struct_value = 1;
2247 /* Easier than making that case work right. */
2250 /* In case this is a static function, note that it has been
2252 if (! TREE_ADDRESSABLE (fndecl))
2253 mark_addressable (fndecl);
2257 #else /* not PCC_STATIC_STRUCT_RETURN */
2259 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2261 if (target && GET_CODE (target) == MEM)
2262 structure_value_addr = XEXP (target, 0);
2265 /* For variable-sized objects, we must be called with a target
2266 specified. If we were to allocate space on the stack here,
2267 we would have no way of knowing when to free it. */
2268 rtx d = assign_temp (TREE_TYPE (exp), 1, 1, 1);
2270 mark_temp_addr_taken (d);
2271 structure_value_addr = XEXP (d, 0);
2275 #endif /* not PCC_STATIC_STRUCT_RETURN */
2278 /* If called function is inline, try to integrate it. */
2282 rtx temp = try_to_integrate (fndecl, actparms, target,
2283 ignore, TREE_TYPE (exp),
2284 structure_value_addr);
2285 if (temp != (rtx) (HOST_WIDE_INT) - 1)
2289 /* Figure out the amount to which the stack should be aligned. */
2290 #ifdef PREFERRED_STACK_BOUNDARY
2291 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2293 preferred_stack_boundary = STACK_BOUNDARY;
2296 /* Operand 0 is a pointer-to-function; get the type of the function. */
2297 funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
2298 if (! POINTER_TYPE_P (funtype))
2300 funtype = TREE_TYPE (funtype);
2302 /* See if this is a call to a function that can return more than once
2303 or a call to longjmp or malloc. */
2304 flags |= special_function_p (fndecl, flags);
2306 if (flags & ECF_MAY_BE_ALLOCA)
2307 current_function_calls_alloca = 1;
2309 /* If struct_value_rtx is 0, it means pass the address
2310 as if it were an extra parameter. */
2311 if (structure_value_addr && struct_value_rtx == 0)
2313 /* If structure_value_addr is a REG other than
2314 virtual_outgoing_args_rtx, we can use always use it. If it
2315 is not a REG, we must always copy it into a register.
2316 If it is virtual_outgoing_args_rtx, we must copy it to another
2317 register in some cases. */
2318 rtx temp = (GET_CODE (structure_value_addr) != REG
2319 || (ACCUMULATE_OUTGOING_ARGS
2320 && stack_arg_under_construction
2321 && structure_value_addr == virtual_outgoing_args_rtx)
2322 ? copy_addr_to_reg (structure_value_addr)
2323 : structure_value_addr);
2326 = tree_cons (error_mark_node,
2327 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2330 structure_value_addr_parm = 1;
2333 /* Count the arguments and set NUM_ACTUALS. */
2334 for (p = actparms, num_actuals = 0; p; p = TREE_CHAIN (p))
2337 /* Compute number of named args.
2338 Normally, don't include the last named arg if anonymous args follow.
2339 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2340 (If no anonymous args follow, the result of list_length is actually
2341 one too large. This is harmless.)
2343 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2344 zero, this machine will be able to place unnamed args that were
2345 passed in registers into the stack. So treat all args as named.
2346 This allows the insns emitting for a specific argument list to be
2347 independent of the function declaration.
2349 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2350 reliable way to pass unnamed args in registers, so we must force
2351 them into memory. */
2353 if ((STRICT_ARGUMENT_NAMING
2354 || ! PRETEND_OUTGOING_VARARGS_NAMED)
2355 && TYPE_ARG_TYPES (funtype) != 0)
2357 = (list_length (TYPE_ARG_TYPES (funtype))
2358 /* Don't include the last named arg. */
2359 - (STRICT_ARGUMENT_NAMING ? 0 : 1)
2360 /* Count the struct value address, if it is passed as a parm. */
2361 + structure_value_addr_parm);
2363 /* If we know nothing, treat all args as named. */
2364 n_named_args = num_actuals;
2366 /* Start updating where the next arg would go.
2368 On some machines (such as the PA) indirect calls have a different
2369 calling convention than normal calls. The last argument in
2370 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2372 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, (fndecl == 0));
2374 /* Make a vector to hold all the information about each arg. */
2375 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
2376 memset ((char *) args, 0, num_actuals * sizeof (struct arg_data));
2378 /* Build up entries in the ARGS array, compute the size of the
2379 arguments into ARGS_SIZE, etc. */
2380 initialize_argument_information (num_actuals, args, &args_size,
2381 n_named_args, actparms, fndecl,
2382 &args_so_far, reg_parm_stack_space,
2383 &old_stack_level, &old_pending_adj,
2384 &must_preallocate, &flags);
2388 /* If this function requires a variable-sized argument list, don't
2389 try to make a cse'able block for this call. We may be able to
2390 do this eventually, but it is too complicated to keep track of
2391 what insns go in the cse'able block and which don't. */
2393 flags &= ~(ECF_CONST | ECF_PURE);
2394 must_preallocate = 1;
2397 /* Now make final decision about preallocating stack space. */
2398 must_preallocate = finalize_must_preallocate (must_preallocate,
2402 /* If the structure value address will reference the stack pointer, we
2403 must stabilize it. We don't need to do this if we know that we are
2404 not going to adjust the stack pointer in processing this call. */
2406 if (structure_value_addr
2407 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2408 || reg_mentioned_p (virtual_outgoing_args_rtx,
2409 structure_value_addr))
2411 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2412 structure_value_addr = copy_to_reg (structure_value_addr);
2414 /* Tail calls can make things harder to debug, and we're traditionally
2415 pushed these optimizations into -O2. Don't try if we're already
2416 expanding a call, as that means we're an argument. Don't try if
2417 there's cleanups, as we know there's code to follow the call.
2419 If rtx_equal_function_value_matters is false, that means we've
2420 finished with regular parsing. Which means that some of the
2421 machinery we use to generate tail-calls is no longer in place.
2422 This is most often true of sjlj-exceptions, which we couldn't
2423 tail-call to anyway. */
2425 if (currently_expanding_call++ != 0
2426 || !flag_optimize_sibling_calls
2427 || !rtx_equal_function_value_matters
2428 || any_pending_cleanups (1)
2430 try_tail_call = try_tail_recursion = 0;
2432 /* Tail recursion fails, when we are not dealing with recursive calls. */
2433 if (!try_tail_recursion
2434 || TREE_CODE (TREE_OPERAND (exp, 0)) != ADDR_EXPR
2435 || TREE_OPERAND (TREE_OPERAND (exp, 0), 0) != current_function_decl)
2436 try_tail_recursion = 0;
2438 /* Rest of purposes for tail call optimizations to fail. */
2440 #ifdef HAVE_sibcall_epilogue
2441 !HAVE_sibcall_epilogue
2446 /* Doing sibling call optimization needs some work, since
2447 structure_value_addr can be allocated on the stack.
2448 It does not seem worth the effort since few optimizable
2449 sibling calls will return a structure. */
2450 || structure_value_addr != NULL_RTX
2451 /* If the register holding the address is a callee saved
2452 register, then we lose. We have no way to prevent that,
2453 so we only allow calls to named functions. */
2454 /* ??? This could be done by having the insn constraints
2455 use a register class that is all call-clobbered. Any
2456 reload insns generated to fix things up would appear
2457 before the sibcall_epilogue. */
2458 || fndecl == NULL_TREE
2459 || (flags & (ECF_RETURNS_TWICE | ECF_LONGJMP))
2460 || TREE_THIS_VOLATILE (fndecl)
2461 || !FUNCTION_OK_FOR_SIBCALL (fndecl)
2462 /* If this function requires more stack slots than the current
2463 function, we cannot change it into a sibling call. */
2464 || args_size.constant > current_function_args_size
2465 /* If the callee pops its own arguments, then it must pop exactly
2466 the same number of arguments as the current function. */
2467 || RETURN_POPS_ARGS (fndecl, funtype, args_size.constant)
2468 != RETURN_POPS_ARGS (current_function_decl,
2469 TREE_TYPE (current_function_decl),
2470 current_function_args_size))
2473 if (try_tail_call || try_tail_recursion)
2476 actparms = NULL_TREE;
2477 /* Ok, we're going to give the tail call the old college try.
2478 This means we're going to evaluate the function arguments
2479 up to three times. There are two degrees of badness we can
2480 encounter, those that can be unsaved and those that can't.
2481 (See unsafe_for_reeval commentary for details.)
2483 Generate a new argument list. Pass safe arguments through
2484 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2485 For hard badness, evaluate them now and put their resulting
2486 rtx in a temporary VAR_DECL.
2488 initialize_argument_information has ordered the array for the
2489 order to be pushed, and we must remember this when reconstructing
2490 the original argument orde. */
2492 if (PUSH_ARGS_REVERSED)
2501 i = num_actuals - 1;
2505 for (; i != end; i += inc)
2507 switch (unsafe_for_reeval (args[i].tree_value))
2512 case 1: /* Mildly unsafe. */
2513 args[i].tree_value = unsave_expr (args[i].tree_value);
2516 case 2: /* Wildly unsafe. */
2518 tree var = build_decl (VAR_DECL, NULL_TREE,
2519 TREE_TYPE (args[i].tree_value));
2521 expand_expr (args[i].tree_value, NULL_RTX,
2522 VOIDmode, EXPAND_NORMAL));
2523 args[i].tree_value = var;
2530 /* We need to build actparms for optimize_tail_recursion. We can
2531 safely trash away TREE_PURPOSE, since it is unused by this
2533 if (try_tail_recursion)
2534 actparms = tree_cons (NULL_TREE, args[i].tree_value, actparms);
2536 /* Expanding one of those dangerous arguments could have added
2537 cleanups, but otherwise give it a whirl. */
2538 if (any_pending_cleanups (1))
2539 try_tail_call = try_tail_recursion = 0;
2542 /* Generate a tail recursion sequence when calling ourselves. */
2544 if (try_tail_recursion)
2546 /* We want to emit any pending stack adjustments before the tail
2547 recursion "call". That way we know any adjustment after the tail
2548 recursion call can be ignored if we indeed use the tail recursion
2550 int save_pending_stack_adjust = pending_stack_adjust;
2551 int save_stack_pointer_delta = stack_pointer_delta;
2553 /* Emit any queued insns now; otherwise they would end up in
2554 only one of the alternates. */
2557 /* Use a new sequence to hold any RTL we generate. We do not even
2558 know if we will use this RTL yet. The final decision can not be
2559 made until after RTL generation for the entire function is
2562 /* If expanding any of the arguments creates cleanups, we can't
2563 do a tailcall. So, we'll need to pop the pending cleanups
2564 list. If, however, all goes well, and there are no cleanups
2565 then the call to expand_start_target_temps will have no
2567 expand_start_target_temps ();
2568 if (optimize_tail_recursion (actparms, get_last_insn ()))
2570 if (any_pending_cleanups (1))
2571 try_tail_call = try_tail_recursion = 0;
2573 tail_recursion_insns = get_insns ();
2575 expand_end_target_temps ();
2578 /* Restore the original pending stack adjustment for the sibling and
2579 normal call cases below. */
2580 pending_stack_adjust = save_pending_stack_adjust;
2581 stack_pointer_delta = save_stack_pointer_delta;
2584 if (profile_arc_flag && (flags & ECF_FORK_OR_EXEC))
2586 /* A fork duplicates the profile information, and an exec discards
2587 it. We can't rely on fork/exec to be paired. So write out the
2588 profile information we have gathered so far, and clear it. */
2589 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2590 is subject to race conditions, just as with multithreaded
2593 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__bb_fork_func"), 0,
2597 /* Ensure current function's preferred stack boundary is at least
2598 what we need. We don't have to increase alignment for recursive
2600 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2601 && fndecl != current_function_decl)
2602 cfun->preferred_stack_boundary = preferred_stack_boundary;
2604 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2606 function_call_count++;
2608 /* We want to make two insn chains; one for a sibling call, the other
2609 for a normal call. We will select one of the two chains after
2610 initial RTL generation is complete. */
2611 for (pass = 0; pass < 2; pass++)
2613 int sibcall_failure = 0;
2614 /* We want to emit ay pending stack adjustments before the tail
2615 recursion "call". That way we know any adjustment after the tail
2616 recursion call can be ignored if we indeed use the tail recursion
2618 int save_pending_stack_adjust = 0;
2619 int save_stack_pointer_delta = 0;
2621 rtx before_call, next_arg_reg;
2625 if (! try_tail_call)
2628 /* Emit any queued insns now; otherwise they would end up in
2629 only one of the alternates. */
2632 /* State variables we need to save and restore between
2634 save_pending_stack_adjust = pending_stack_adjust;
2635 save_stack_pointer_delta = stack_pointer_delta;
2638 flags &= ~ECF_SIBCALL;
2640 flags |= ECF_SIBCALL;
2642 /* Other state variables that we must reinitialize each time
2643 through the loop (that are not initialized by the loop itself). */
2647 /* Start a new sequence for the normal call case.
2649 From this point on, if the sibling call fails, we want to set
2650 sibcall_failure instead of continuing the loop. */
2655 /* We know at this point that there are not currently any
2656 pending cleanups. If, however, in the process of evaluating
2657 the arguments we were to create some, we'll need to be
2658 able to get rid of them. */
2659 expand_start_target_temps ();
2662 /* Don't let pending stack adjusts add up to too much.
2663 Also, do all pending adjustments now if there is any chance
2664 this might be a call to alloca or if we are expanding a sibling
2666 if (pending_stack_adjust >= 32
2667 || (pending_stack_adjust > 0 && (flags & ECF_MAY_BE_ALLOCA))
2669 do_pending_stack_adjust ();
2671 /* When calling a const function, we must pop the stack args right away,
2672 so that the pop is deleted or moved with the call. */
2673 if (flags & (ECF_CONST | ECF_PURE))
2676 /* Push the temporary stack slot level so that we can free any
2677 temporaries we make. */
2680 #ifdef FINAL_REG_PARM_STACK_SPACE
2681 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2684 /* Precompute any arguments as needed. */
2686 precompute_arguments (flags, num_actuals, args);
2688 /* Now we are about to start emitting insns that can be deleted
2689 if a libcall is deleted. */
2690 if (flags & (ECF_CONST | ECF_PURE | ECF_MALLOC))
2693 adjusted_args_size = args_size;
2694 /* Compute the actual size of the argument block required. The variable
2695 and constant sizes must be combined, the size may have to be rounded,
2696 and there may be a minimum required size. When generating a sibcall
2697 pattern, do not round up, since we'll be re-using whatever space our
2699 unadjusted_args_size
2700 = compute_argument_block_size (reg_parm_stack_space,
2701 &adjusted_args_size,
2703 : preferred_stack_boundary));
2705 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2707 /* The argument block when performing a sibling call is the
2708 incoming argument block. */
2711 argblock = virtual_incoming_args_rtx;
2712 stored_args_map = sbitmap_alloc (args_size.constant);
2713 sbitmap_zero (stored_args_map);
2716 /* If we have no actual push instructions, or shouldn't use them,
2717 make space for all args right now. */
2718 else if (adjusted_args_size.var != 0)
2720 if (old_stack_level == 0)
2722 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2723 old_pending_adj = pending_stack_adjust;
2724 pending_stack_adjust = 0;
2725 /* stack_arg_under_construction says whether a stack arg is
2726 being constructed at the old stack level. Pushing the stack
2727 gets a clean outgoing argument block. */
2728 old_stack_arg_under_construction = stack_arg_under_construction;
2729 stack_arg_under_construction = 0;
2731 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2735 /* Note that we must go through the motions of allocating an argument
2736 block even if the size is zero because we may be storing args
2737 in the area reserved for register arguments, which may be part of
2740 int needed = adjusted_args_size.constant;
2742 /* Store the maximum argument space used. It will be pushed by
2743 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2746 if (needed > current_function_outgoing_args_size)
2747 current_function_outgoing_args_size = needed;
2749 if (must_preallocate)
2751 if (ACCUMULATE_OUTGOING_ARGS)
2753 /* Since the stack pointer will never be pushed, it is
2754 possible for the evaluation of a parm to clobber
2755 something we have already written to the stack.
2756 Since most function calls on RISC machines do not use
2757 the stack, this is uncommon, but must work correctly.
2759 Therefore, we save any area of the stack that was already
2760 written and that we are using. Here we set up to do this
2761 by making a new stack usage map from the old one. The
2762 actual save will be done by store_one_arg.
2764 Another approach might be to try to reorder the argument
2765 evaluations to avoid this conflicting stack usage. */
2767 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2768 /* Since we will be writing into the entire argument area,
2769 the map must be allocated for its entire size, not just
2770 the part that is the responsibility of the caller. */
2771 needed += reg_parm_stack_space;
2774 #ifdef ARGS_GROW_DOWNWARD
2775 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2778 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2782 = (char *) alloca (highest_outgoing_arg_in_use);
2784 if (initial_highest_arg_in_use)
2785 memcpy (stack_usage_map, initial_stack_usage_map,
2786 initial_highest_arg_in_use);
2788 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2789 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2790 (highest_outgoing_arg_in_use
2791 - initial_highest_arg_in_use));
2794 /* The address of the outgoing argument list must not be
2795 copied to a register here, because argblock would be left
2796 pointing to the wrong place after the call to
2797 allocate_dynamic_stack_space below. */
2799 argblock = virtual_outgoing_args_rtx;
2803 if (inhibit_defer_pop == 0)
2805 /* Try to reuse some or all of the pending_stack_adjust
2806 to get this space. */
2808 = (combine_pending_stack_adjustment_and_call
2809 (unadjusted_args_size,
2810 &adjusted_args_size,
2811 preferred_unit_stack_boundary));
2813 /* combine_pending_stack_adjustment_and_call computes
2814 an adjustment before the arguments are allocated.
2815 Account for them and see whether or not the stack
2816 needs to go up or down. */
2817 needed = unadjusted_args_size - needed;
2821 /* We're releasing stack space. */
2822 /* ??? We can avoid any adjustment at all if we're
2823 already aligned. FIXME. */
2824 pending_stack_adjust = -needed;
2825 do_pending_stack_adjust ();
2829 /* We need to allocate space. We'll do that in
2830 push_block below. */
2831 pending_stack_adjust = 0;
2834 /* Special case this because overhead of `push_block' in
2835 this case is non-trivial. */
2837 argblock = virtual_outgoing_args_rtx;
2839 argblock = push_block (GEN_INT (needed), 0, 0);
2841 /* We only really need to call `copy_to_reg' in the case
2842 where push insns are going to be used to pass ARGBLOCK
2843 to a function call in ARGS. In that case, the stack
2844 pointer changes value from the allocation point to the
2845 call point, and hence the value of
2846 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2847 as well always do it. */
2848 argblock = copy_to_reg (argblock);
2850 /* The save/restore code in store_one_arg handles all
2851 cases except one: a constructor call (including a C
2852 function returning a BLKmode struct) to initialize
2854 if (stack_arg_under_construction)
2856 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2857 rtx push_size = GEN_INT (reg_parm_stack_space
2858 + adjusted_args_size.constant);
2860 rtx push_size = GEN_INT (adjusted_args_size.constant);
2862 if (old_stack_level == 0)
2864 emit_stack_save (SAVE_BLOCK, &old_stack_level,
2866 old_pending_adj = pending_stack_adjust;
2867 pending_stack_adjust = 0;
2868 /* stack_arg_under_construction says whether a stack
2869 arg is being constructed at the old stack level.
2870 Pushing the stack gets a clean outgoing argument
2872 old_stack_arg_under_construction
2873 = stack_arg_under_construction;
2874 stack_arg_under_construction = 0;
2875 /* Make a new map for the new argument list. */
2876 stack_usage_map = (char *)
2877 alloca (highest_outgoing_arg_in_use);
2878 memset (stack_usage_map, 0, highest_outgoing_arg_in_use);
2879 highest_outgoing_arg_in_use = 0;
2881 allocate_dynamic_stack_space (push_size, NULL_RTX,
2884 /* If argument evaluation might modify the stack pointer,
2885 copy the address of the argument list to a register. */
2886 for (i = 0; i < num_actuals; i++)
2887 if (args[i].pass_on_stack)
2889 argblock = copy_addr_to_reg (argblock);
2896 compute_argument_addresses (args, argblock, num_actuals);
2898 #ifdef PREFERRED_STACK_BOUNDARY
2899 /* If we push args individually in reverse order, perform stack alignment
2900 before the first push (the last arg). */
2901 if (PUSH_ARGS_REVERSED && argblock == 0
2902 && adjusted_args_size.constant != unadjusted_args_size)
2904 /* When the stack adjustment is pending, we get better code
2905 by combining the adjustments. */
2906 if (pending_stack_adjust
2907 && ! (flags & (ECF_CONST | ECF_PURE))
2908 && ! inhibit_defer_pop)
2910 pending_stack_adjust
2911 = (combine_pending_stack_adjustment_and_call
2912 (unadjusted_args_size,
2913 &adjusted_args_size,
2914 preferred_unit_stack_boundary));
2915 do_pending_stack_adjust ();
2917 else if (argblock == 0)
2918 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2919 - unadjusted_args_size));
2921 /* Now that the stack is properly aligned, pops can't safely
2922 be deferred during the evaluation of the arguments. */
2926 /* Don't try to defer pops if preallocating, not even from the first arg,
2927 since ARGBLOCK probably refers to the SP. */
2931 funexp = rtx_for_function_call (fndecl, exp);
2933 /* Figure out the register where the value, if any, will come back. */
2935 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2936 && ! structure_value_addr)
2938 if (pcc_struct_value)
2939 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2940 fndecl, (pass == 0));
2942 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
2945 /* Precompute all register parameters. It isn't safe to compute anything
2946 once we have started filling any specific hard regs. */
2947 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2949 #ifdef REG_PARM_STACK_SPACE
2950 /* Save the fixed argument area if it's part of the caller's frame and
2951 is clobbered by argument setup for this call. */
2952 if (ACCUMULATE_OUTGOING_ARGS && pass)
2953 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2954 &low_to_save, &high_to_save);
2957 /* Now store (and compute if necessary) all non-register parms.
2958 These come before register parms, since they can require block-moves,
2959 which could clobber the registers used for register parms.
2960 Parms which have partial registers are not stored here,
2961 but we do preallocate space here if they want that. */
2963 for (i = 0; i < num_actuals; i++)
2964 if (args[i].reg == 0 || args[i].pass_on_stack)
2966 rtx before_arg = get_last_insn ();
2968 if (store_one_arg (&args[i], argblock, flags,
2969 adjusted_args_size.var != 0,
2970 reg_parm_stack_space)
2972 && check_sibcall_argument_overlap (before_arg,
2974 sibcall_failure = 1;
2977 /* If we have a parm that is passed in registers but not in memory
2978 and whose alignment does not permit a direct copy into registers,
2979 make a group of pseudos that correspond to each register that we
2981 if (STRICT_ALIGNMENT)
2982 store_unaligned_arguments_into_pseudos (args, num_actuals);
2984 /* Now store any partially-in-registers parm.
2985 This is the last place a block-move can happen. */
2987 for (i = 0; i < num_actuals; i++)
2988 if (args[i].partial != 0 && ! args[i].pass_on_stack)
2990 rtx before_arg = get_last_insn ();
2992 if (store_one_arg (&args[i], argblock, flags,
2993 adjusted_args_size.var != 0,
2994 reg_parm_stack_space)
2996 && check_sibcall_argument_overlap (before_arg,
2998 sibcall_failure = 1;
3001 #ifdef PREFERRED_STACK_BOUNDARY
3002 /* If we pushed args in forward order, perform stack alignment
3003 after pushing the last arg. */
3004 if (!PUSH_ARGS_REVERSED && argblock == 0)
3005 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3006 - unadjusted_args_size));
3009 /* If register arguments require space on the stack and stack space
3010 was not preallocated, allocate stack space here for arguments
3011 passed in registers. */
3012 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3013 if (!ACCUMULATE_OUTGOING_ARGS
3014 && must_preallocate == 0 && reg_parm_stack_space > 0)
3015 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3018 /* Pass the function the address in which to return a
3020 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3022 emit_move_insn (struct_value_rtx,
3024 force_operand (structure_value_addr,
3027 /* Mark the memory for the aggregate as write-only. */
3028 if (current_function_check_memory_usage)
3029 emit_library_call (chkr_set_right_libfunc, LCT_CONST_MAKE_BLOCK,
3031 structure_value_addr, ptr_mode,
3032 GEN_INT (struct_value_size),
3033 TYPE_MODE (sizetype),
3034 GEN_INT (MEMORY_USE_WO),
3035 TYPE_MODE (integer_type_node));
3037 if (GET_CODE (struct_value_rtx) == REG)
3038 use_reg (&call_fusage, struct_value_rtx);
3041 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
3042 reg_parm_seen, pass == 0);
3044 load_register_parameters (args, num_actuals, &call_fusage, flags);
3046 /* Perform postincrements before actually calling the function. */
3049 /* Save a pointer to the last insn before the call, so that we can
3050 later safely search backwards to find the CALL_INSN. */
3051 before_call = get_last_insn ();
3053 /* Set up next argument register. For sibling calls on machines
3054 with register windows this should be the incoming register. */
3055 #ifdef FUNCTION_INCOMING_ARG
3057 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
3061 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
3064 /* All arguments and registers used for the call must be set up by
3067 #ifdef PREFERRED_STACK_BOUNDARY
3068 /* Stack must be properly aligned now. */
3069 if (pass && stack_pointer_delta % preferred_unit_stack_boundary)
3073 /* Generate the actual call instruction. */
3074 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
3075 adjusted_args_size.constant, struct_value_size,
3076 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3079 /* Verify that we've deallocated all the stack we used. */
3081 && old_stack_allocated != stack_pointer_delta - pending_stack_adjust)
3084 /* If call is cse'able, make appropriate pair of reg-notes around it.
3085 Test valreg so we don't crash; may safely ignore `const'
3086 if return type is void. Disable for PARALLEL return values, because
3087 we have no way to move such values into a pseudo register. */
3089 && (flags & (ECF_CONST | ECF_PURE))
3090 && valreg != 0 && GET_CODE (valreg) != PARALLEL)
3093 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3096 /* Mark the return value as a pointer if needed. */
3097 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3098 mark_reg_pointer (temp, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
3100 /* Construct an "equal form" for the value which mentions all the
3101 arguments in order as well as the function name. */
3102 for (i = 0; i < num_actuals; i++)
3103 note = gen_rtx_EXPR_LIST (VOIDmode, args[i].initial_value, note);
3104 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
3106 insns = get_insns ();
3109 if (flags & ECF_PURE)
3110 note = gen_rtx_EXPR_LIST (VOIDmode,
3111 gen_rtx_USE (VOIDmode,
3112 gen_rtx_MEM (BLKmode,
3113 gen_rtx_SCRATCH (VOIDmode))), note);
3115 emit_libcall_block (insns, temp, valreg, note);
3119 else if (flags & (ECF_CONST | ECF_PURE))
3121 /* Otherwise, just write out the sequence without a note. */
3122 rtx insns = get_insns ();
3127 else if (flags & ECF_MALLOC)
3129 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3132 /* The return value from a malloc-like function is a pointer. */
3133 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3134 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3136 emit_move_insn (temp, valreg);
3138 /* The return value from a malloc-like function can not alias
3140 last = get_last_insn ();
3142 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
3144 /* Write out the sequence. */
3145 insns = get_insns ();
3151 /* For calls to `setjmp', etc., inform flow.c it should complain
3152 if nonvolatile values are live. For functions that cannot return,
3153 inform flow that control does not fall through. */
3155 if ((flags & (ECF_RETURNS_TWICE | ECF_NORETURN | ECF_LONGJMP)) || pass == 0)
3157 /* The barrier or NOTE_INSN_SETJMP note must be emitted
3158 immediately after the CALL_INSN. Some ports emit more
3159 than just a CALL_INSN above, so we must search for it here. */
3161 rtx last = get_last_insn ();
3162 while (GET_CODE (last) != CALL_INSN)
3164 last = PREV_INSN (last);
3165 /* There was no CALL_INSN? */
3166 if (last == before_call)
3170 if (flags & ECF_RETURNS_TWICE)
3172 emit_note_after (NOTE_INSN_SETJMP, last);
3173 current_function_calls_setjmp = 1;
3176 emit_barrier_after (last);
3179 if (flags & ECF_LONGJMP)
3180 current_function_calls_longjmp = 1;
3182 /* If this function is returning into a memory location marked as
3183 readonly, it means it is initializing that location. But we normally
3184 treat functions as not clobbering such locations, so we need to
3185 specify that this one does. */
3186 if (target != 0 && GET_CODE (target) == MEM
3187 && structure_value_addr != 0 && RTX_UNCHANGING_P (target))
3188 emit_insn (gen_rtx_CLOBBER (VOIDmode, target));
3190 /* If value type not void, return an rtx for the value. */
3192 /* If there are cleanups to be called, don't use a hard reg as target.
3193 We need to double check this and see if it matters anymore. */
3194 if (any_pending_cleanups (1))
3196 if (target && REG_P (target)
3197 && REGNO (target) < FIRST_PSEUDO_REGISTER)
3199 sibcall_failure = 1;
3202 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
3205 target = const0_rtx;
3207 else if (structure_value_addr)
3209 if (target == 0 || GET_CODE (target) != MEM)
3212 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3213 memory_address (TYPE_MODE (TREE_TYPE (exp)),
3214 structure_value_addr));
3215 set_mem_attributes (target, exp, 1);
3218 else if (pcc_struct_value)
3220 /* This is the special C++ case where we need to
3221 know what the true target was. We take care to
3222 never use this value more than once in one expression. */
3223 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3224 copy_to_reg (valreg));
3225 set_mem_attributes (target, exp, 1);
3227 /* Handle calls that return values in multiple non-contiguous locations.
3228 The Irix 6 ABI has examples of this. */
3229 else if (GET_CODE (valreg) == PARALLEL)
3233 /* This will only be assigned once, so it can be readonly. */
3234 tree nt = build_qualified_type (TREE_TYPE (exp),
3235 (TYPE_QUALS (TREE_TYPE (exp))
3236 | TYPE_QUAL_CONST));
3238 target = assign_temp (nt, 0, 1, 1);
3239 preserve_temp_slots (target);
3242 if (! rtx_equal_p (target, valreg))
3243 emit_group_store (target, valreg,
3244 int_size_in_bytes (TREE_TYPE (exp)),
3245 TYPE_ALIGN (TREE_TYPE (exp)));
3247 /* We can not support sibling calls for this case. */
3248 sibcall_failure = 1;
3251 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
3252 && GET_MODE (target) == GET_MODE (valreg))
3254 /* TARGET and VALREG cannot be equal at this point because the
3255 latter would not have REG_FUNCTION_VALUE_P true, while the
3256 former would if it were referring to the same register.
3258 If they refer to the same register, this move will be a no-op,
3259 except when function inlining is being done. */
3260 emit_move_insn (target, valreg);
3262 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3264 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3266 /* We can not support sibling calls for this case. */
3267 sibcall_failure = 1;
3270 target = copy_to_reg (valreg);
3272 #ifdef PROMOTE_FUNCTION_RETURN
3273 /* If we promoted this return value, make the proper SUBREG. TARGET
3274 might be const0_rtx here, so be careful. */
3275 if (GET_CODE (target) == REG
3276 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3277 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3279 tree type = TREE_TYPE (exp);
3280 int unsignedp = TREE_UNSIGNED (type);
3283 /* If we don't promote as expected, something is wrong. */
3284 if (GET_MODE (target)
3285 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
3288 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3289 && GET_MODE_SIZE (GET_MODE (target))
3290 > GET_MODE_SIZE (TYPE_MODE (type)))
3292 offset = GET_MODE_SIZE (GET_MODE (target))
3293 - GET_MODE_SIZE (TYPE_MODE (type));
3294 if (! BYTES_BIG_ENDIAN)
3295 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3296 else if (! WORDS_BIG_ENDIAN)
3297 offset %= UNITS_PER_WORD;
3299 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3300 SUBREG_PROMOTED_VAR_P (target) = 1;
3301 SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
3305 /* If size of args is variable or this was a constructor call for a stack
3306 argument, restore saved stack-pointer value. */
3308 if (old_stack_level && ! (flags & ECF_SP_DEPRESSED))
3310 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3311 pending_stack_adjust = old_pending_adj;
3312 stack_arg_under_construction = old_stack_arg_under_construction;
3313 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3314 stack_usage_map = initial_stack_usage_map;
3315 sibcall_failure = 1;
3317 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3319 #ifdef REG_PARM_STACK_SPACE
3322 restore_fixed_argument_area (save_area, argblock,
3323 high_to_save, low_to_save);
3327 /* If we saved any argument areas, restore them. */
3328 for (i = 0; i < num_actuals; i++)
3329 if (args[i].save_area)
3331 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3333 = gen_rtx_MEM (save_mode,
3334 memory_address (save_mode,
3335 XEXP (args[i].stack_slot, 0)));
3337 if (save_mode != BLKmode)
3338 emit_move_insn (stack_area, args[i].save_area);
3340 emit_block_move (stack_area,
3341 validize_mem (args[i].save_area),
3342 GEN_INT (args[i].size.constant),
3346 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3347 stack_usage_map = initial_stack_usage_map;
3350 /* If this was alloca, record the new stack level for nonlocal gotos.
3351 Check for the handler slots since we might not have a save area
3352 for non-local gotos. */
3354 if ((flags & ECF_MAY_BE_ALLOCA) && nonlocal_goto_handler_slots != 0)
3355 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3359 /* Free up storage we no longer need. */
3360 for (i = 0; i < num_actuals; ++i)
3361 if (args[i].aligned_regs)
3362 free (args[i].aligned_regs);
3366 /* Undo the fake expand_start_target_temps we did earlier. If
3367 there had been any cleanups created, we've already set
3369 expand_end_target_temps ();
3372 insns = get_insns ();
3377 tail_call_insns = insns;
3379 /* Restore the pending stack adjustment now that we have
3380 finished generating the sibling call sequence. */
3382 pending_stack_adjust = save_pending_stack_adjust;
3383 stack_pointer_delta = save_stack_pointer_delta;
3385 /* Prepare arg structure for next iteration. */
3386 for (i = 0; i < num_actuals; i++)
3389 args[i].aligned_regs = 0;
3393 sbitmap_free (stored_args_map);
3396 normal_call_insns = insns;
3398 /* If something prevents making this a sibling call,
3399 zero out the sequence. */
3400 if (sibcall_failure)
3401 tail_call_insns = NULL_RTX;
3404 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3405 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3406 can happen if the arguments to this function call an inline
3407 function who's expansion contains another CALL_PLACEHOLDER.
3409 If there are any C_Ps in any of these sequences, replace them
3410 with their normal call. */
3412 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3413 if (GET_CODE (insn) == CALL_INSN
3414 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3415 replace_call_placeholder (insn, sibcall_use_normal);
3417 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
3418 if (GET_CODE (insn) == CALL_INSN
3419 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3420 replace_call_placeholder (insn, sibcall_use_normal);
3422 for (insn = tail_recursion_insns; insn; insn = NEXT_INSN (insn))
3423 if (GET_CODE (insn) == CALL_INSN
3424 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3425 replace_call_placeholder (insn, sibcall_use_normal);
3427 /* If this was a potential tail recursion site, then emit a
3428 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3429 One of them will be selected later. */
3430 if (tail_recursion_insns || tail_call_insns)
3432 /* The tail recursion label must be kept around. We could expose
3433 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3434 and makes determining true tail recursion sites difficult.
3436 So we set LABEL_PRESERVE_P here, then clear it when we select
3437 one of the call sequences after rtl generation is complete. */
3438 if (tail_recursion_insns)
3439 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3440 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3442 tail_recursion_insns,
3443 tail_recursion_label));
3446 emit_insns (normal_call_insns);
3448 currently_expanding_call--;
3450 /* If this function returns with the stack pointer depressed, ensure
3451 this block saves and restores the stack pointer, show it was
3452 changed, and adjust for any outgoing arg space. */
3453 if (flags & ECF_SP_DEPRESSED)
3455 clear_pending_stack_adjust ();
3456 emit_insn (gen_rtx (CLOBBER, VOIDmode, stack_pointer_rtx));
3457 emit_move_insn (virtual_stack_dynamic_rtx, stack_pointer_rtx);
3458 save_stack_pointer ();
3464 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3465 The RETVAL parameter specifies whether return value needs to be saved, other
3466 parameters are documented in the emit_library_call function below. */
3468 emit_library_call_value_1 (retval, orgfun, value, fn_type, outmode, nargs, p)
3472 enum libcall_type fn_type;
3473 enum machine_mode outmode;
3477 /* Total size in bytes of all the stack-parms scanned so far. */
3478 struct args_size args_size;
3479 /* Size of arguments before any adjustments (such as rounding). */
3480 struct args_size original_args_size;
3481 register int argnum;
3485 struct args_size alignment_pad;
3487 CUMULATIVE_ARGS args_so_far;
3491 enum machine_mode mode;
3494 struct args_size offset;
3495 struct args_size size;
3499 int old_inhibit_defer_pop = inhibit_defer_pop;
3500 rtx call_fusage = 0;
3503 int pcc_struct_value = 0;
3504 int struct_value_size = 0;
3506 int reg_parm_stack_space = 0;
3510 #ifdef REG_PARM_STACK_SPACE
3511 /* Define the boundary of the register parm stack space that needs to be
3513 int low_to_save = -1, high_to_save = 0;
3514 rtx save_area = 0; /* Place that it is saved. */
3517 /* Size of the stack reserved for parameter registers. */
3518 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3519 char *initial_stack_usage_map = stack_usage_map;
3521 #ifdef REG_PARM_STACK_SPACE
3522 #ifdef MAYBE_REG_PARM_STACK_SPACE
3523 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3525 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3529 /* By default, library functions can not throw. */
3530 flags = ECF_NOTHROW;
3537 /* Nothing to do here. */
3539 case LCT_CONST_MAKE_BLOCK:
3542 case LCT_PURE_MAKE_BLOCK:
3546 flags |= ECF_NORETURN;
3549 flags = ECF_NORETURN;
3554 #ifdef PREFERRED_STACK_BOUNDARY
3555 /* Ensure current function's preferred stack boundary is at least
3557 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3558 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 && aggregate_value_p (type_for_mode (outmode, 0)))
3565 #ifdef PCC_STATIC_STRUCT_RETURN
3567 = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
3569 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3570 pcc_struct_value = 1;
3572 value = gen_reg_rtx (outmode);
3573 #else /* not PCC_STATIC_STRUCT_RETURN */
3574 struct_value_size = GET_MODE_SIZE (outmode);
3575 if (value != 0 && GET_CODE (value) == MEM)
3578 mem_value = assign_temp (type_for_mode (outmode, 0), 0, 1, 1);
3581 /* This call returns a big structure. */
3582 flags &= ~(ECF_CONST | ECF_PURE);
3585 /* ??? Unfinished: must pass the memory address as an argument. */
3587 /* Copy all the libcall-arguments out of the varargs data
3588 and into a vector ARGVEC.
3590 Compute how to pass each argument. We only support a very small subset
3591 of the full argument passing conventions to limit complexity here since
3592 library functions shouldn't have many args. */
3594 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
3595 memset ((char *) argvec, 0, (nargs + 1) * sizeof (struct arg));
3597 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3598 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far, outmode, fun);
3600 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
3603 args_size.constant = 0;
3608 /* Now we are about to start emitting insns that can be deleted
3609 if a libcall is deleted. */
3610 if (flags & (ECF_CONST | ECF_PURE))
3615 /* If there's a structure value address to be passed,
3616 either pass it in the special place, or pass it as an extra argument. */
3617 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
3619 rtx addr = XEXP (mem_value, 0);
3622 /* Make sure it is a reasonable operand for a move or push insn. */
3623 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3624 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3625 addr = force_operand (addr, NULL_RTX);
3627 argvec[count].value = addr;
3628 argvec[count].mode = Pmode;
3629 argvec[count].partial = 0;
3631 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3632 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3633 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3637 locate_and_pad_parm (Pmode, NULL_TREE,
3638 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3641 argvec[count].reg != 0,
3643 NULL_TREE, &args_size, &argvec[count].offset,
3644 &argvec[count].size, &alignment_pad);
3646 if (argvec[count].reg == 0 || argvec[count].partial != 0
3647 || reg_parm_stack_space > 0)
3648 args_size.constant += argvec[count].size.constant;
3650 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3655 for (; count < nargs; count++)
3657 rtx val = va_arg (p, rtx);
3658 enum machine_mode mode = va_arg (p, enum machine_mode);
3660 /* We cannot convert the arg value to the mode the library wants here;
3661 must do it earlier where we know the signedness of the arg. */
3663 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3666 /* On some machines, there's no way to pass a float to a library fcn.
3667 Pass it as a double instead. */
3668 #ifdef LIBGCC_NEEDS_DOUBLE
3669 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
3670 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
3673 /* There's no need to call protect_from_queue, because
3674 either emit_move_insn or emit_push_insn will do that. */
3676 /* Make sure it is a reasonable operand for a move or push insn. */
3677 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3678 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3679 val = force_operand (val, NULL_RTX);
3681 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3682 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3686 #ifdef FUNCTION_ARG_CALLEE_COPIES
3687 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far, mode,
3692 if (GET_MODE (val) == MEM && ! must_copy)
3696 slot = assign_temp (type_for_mode (mode, 0), 0, 1, 1);
3697 emit_move_insn (slot, val);
3701 tree type = type_for_mode (mode, 0);
3703 slot = gen_rtx_MEM (mode,
3704 expand_expr (build1 (ADDR_EXPR,
3707 make_tree (type, val)),
3708 NULL_RTX, VOIDmode, 0));
3711 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3712 gen_rtx_USE (VOIDmode, slot),
3715 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3716 gen_rtx_CLOBBER (VOIDmode,
3721 val = force_operand (XEXP (slot, 0), NULL_RTX);
3725 argvec[count].value = val;
3726 argvec[count].mode = mode;
3728 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3730 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3731 argvec[count].partial
3732 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3734 argvec[count].partial = 0;
3737 locate_and_pad_parm (mode, NULL_TREE,
3738 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3741 argvec[count].reg != 0,
3743 NULL_TREE, &args_size, &argvec[count].offset,
3744 &argvec[count].size, &alignment_pad);
3746 if (argvec[count].size.var)
3749 if (reg_parm_stack_space == 0 && argvec[count].partial)
3750 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
3752 if (argvec[count].reg == 0 || argvec[count].partial != 0
3753 || reg_parm_stack_space > 0)
3754 args_size.constant += argvec[count].size.constant;
3756 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3759 #ifdef FINAL_REG_PARM_STACK_SPACE
3760 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3763 /* If this machine requires an external definition for library
3764 functions, write one out. */
3765 assemble_external_libcall (fun);
3767 original_args_size = args_size;
3768 #ifdef PREFERRED_STACK_BOUNDARY
3769 args_size.constant = (((args_size.constant
3770 + stack_pointer_delta
3774 - stack_pointer_delta);
3777 args_size.constant = MAX (args_size.constant,
3778 reg_parm_stack_space);
3780 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3781 args_size.constant -= reg_parm_stack_space;
3784 if (args_size.constant > current_function_outgoing_args_size)
3785 current_function_outgoing_args_size = args_size.constant;
3787 if (ACCUMULATE_OUTGOING_ARGS)
3789 /* Since the stack pointer will never be pushed, it is possible for
3790 the evaluation of a parm to clobber something we have already
3791 written to the stack. Since most function calls on RISC machines
3792 do not use the stack, this is uncommon, but must work correctly.
3794 Therefore, we save any area of the stack that was already written
3795 and that we are using. Here we set up to do this by making a new
3796 stack usage map from the old one.
3798 Another approach might be to try to reorder the argument
3799 evaluations to avoid this conflicting stack usage. */
3801 needed = args_size.constant;
3803 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3804 /* Since we will be writing into the entire argument area, the
3805 map must be allocated for its entire size, not just the part that
3806 is the responsibility of the caller. */
3807 needed += reg_parm_stack_space;
3810 #ifdef ARGS_GROW_DOWNWARD
3811 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3814 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3817 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
3819 if (initial_highest_arg_in_use)
3820 memcpy (stack_usage_map, initial_stack_usage_map,
3821 initial_highest_arg_in_use);
3823 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3824 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3825 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3828 /* We must be careful to use virtual regs before they're instantiated,
3829 and real regs afterwards. Loop optimization, for example, can create
3830 new libcalls after we've instantiated the virtual regs, and if we
3831 use virtuals anyway, they won't match the rtl patterns. */
3833 if (virtuals_instantiated)
3834 argblock = plus_constant (stack_pointer_rtx, STACK_POINTER_OFFSET);
3836 argblock = virtual_outgoing_args_rtx;
3841 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3844 #ifdef PREFERRED_STACK_BOUNDARY
3845 /* If we push args individually in reverse order, perform stack alignment
3846 before the first push (the last arg). */
3847 if (argblock == 0 && PUSH_ARGS_REVERSED)
3848 anti_adjust_stack (GEN_INT (args_size.constant
3849 - original_args_size.constant));
3852 if (PUSH_ARGS_REVERSED)
3863 #ifdef REG_PARM_STACK_SPACE
3864 if (ACCUMULATE_OUTGOING_ARGS)
3866 /* The argument list is the property of the called routine and it
3867 may clobber it. If the fixed area has been used for previous
3868 parameters, we must save and restore it.
3870 Here we compute the boundary of the that needs to be saved, if any. */
3872 #ifdef ARGS_GROW_DOWNWARD
3873 for (count = 0; count < reg_parm_stack_space + 1; count++)
3875 for (count = 0; count < reg_parm_stack_space; count++)
3878 if (count >= highest_outgoing_arg_in_use
3879 || stack_usage_map[count] == 0)
3882 if (low_to_save == -1)
3883 low_to_save = count;
3885 high_to_save = count;
3888 if (low_to_save >= 0)
3890 int num_to_save = high_to_save - low_to_save + 1;
3891 enum machine_mode save_mode
3892 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
3895 /* If we don't have the required alignment, must do this in BLKmode. */
3896 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
3897 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
3898 save_mode = BLKmode;
3900 #ifdef ARGS_GROW_DOWNWARD
3901 stack_area = gen_rtx_MEM (save_mode,
3902 memory_address (save_mode,
3903 plus_constant (argblock,
3906 stack_area = gen_rtx_MEM (save_mode,
3907 memory_address (save_mode,
3908 plus_constant (argblock,
3911 if (save_mode == BLKmode)
3913 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
3914 emit_block_move (validize_mem (save_area), stack_area,
3915 GEN_INT (num_to_save), PARM_BOUNDARY);
3919 save_area = gen_reg_rtx (save_mode);
3920 emit_move_insn (save_area, stack_area);
3926 /* Push the args that need to be pushed. */
3928 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3929 are to be pushed. */
3930 for (count = 0; count < nargs; count++, argnum += inc)
3932 register enum machine_mode mode = argvec[argnum].mode;
3933 register rtx val = argvec[argnum].value;
3934 rtx reg = argvec[argnum].reg;
3935 int partial = argvec[argnum].partial;
3936 int lower_bound = 0, upper_bound = 0, i;
3938 if (! (reg != 0 && partial == 0))
3940 if (ACCUMULATE_OUTGOING_ARGS)
3942 /* If this is being stored into a pre-allocated, fixed-size,
3943 stack area, save any previous data at that location. */
3945 #ifdef ARGS_GROW_DOWNWARD
3946 /* stack_slot is negative, but we want to index stack_usage_map
3947 with positive values. */
3948 upper_bound = -argvec[argnum].offset.constant + 1;
3949 lower_bound = upper_bound - argvec[argnum].size.constant;
3951 lower_bound = argvec[argnum].offset.constant;
3952 upper_bound = lower_bound + argvec[argnum].size.constant;
3955 for (i = lower_bound; i < upper_bound; i++)
3956 if (stack_usage_map[i]
3957 /* Don't store things in the fixed argument area at this
3958 point; it has already been saved. */
3959 && i > reg_parm_stack_space)
3962 if (i != upper_bound)
3964 /* We need to make a save area. See what mode we can make
3966 enum machine_mode save_mode
3967 = mode_for_size (argvec[argnum].size.constant
3975 plus_constant (argblock,
3976 argvec[argnum].offset.constant)));
3977 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3979 emit_move_insn (argvec[argnum].save_area, stack_area);
3983 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
3984 argblock, GEN_INT (argvec[argnum].offset.constant),
3985 reg_parm_stack_space, ARGS_SIZE_RTX (alignment_pad));
3987 /* Now mark the segment we just used. */
3988 if (ACCUMULATE_OUTGOING_ARGS)
3989 for (i = lower_bound; i < upper_bound; i++)
3990 stack_usage_map[i] = 1;
3996 #ifdef PREFERRED_STACK_BOUNDARY
3997 /* If we pushed args in forward order, perform stack alignment
3998 after pushing the last arg. */
3999 if (argblock == 0 && !PUSH_ARGS_REVERSED)
4000 anti_adjust_stack (GEN_INT (args_size.constant
4001 - original_args_size.constant));
4004 if (PUSH_ARGS_REVERSED)
4009 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0, 0);
4011 /* Now load any reg parms into their regs. */
4013 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4014 are to be pushed. */
4015 for (count = 0; count < nargs; count++, argnum += inc)
4017 register rtx val = argvec[argnum].value;
4018 rtx reg = argvec[argnum].reg;
4019 int partial = argvec[argnum].partial;
4021 /* Handle calls that pass values in multiple non-contiguous
4022 locations. The PA64 has examples of this for library calls. */
4023 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4024 emit_group_load (reg, val,
4025 GET_MODE_SIZE (GET_MODE (val)),
4026 GET_MODE_ALIGNMENT (GET_MODE (val)));
4027 else if (reg != 0 && partial == 0)
4028 emit_move_insn (reg, val);
4033 /* Any regs containing parms remain in use through the call. */
4034 for (count = 0; count < nargs; count++)
4036 rtx reg = argvec[count].reg;
4037 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4038 use_group_regs (&call_fusage, reg);
4040 use_reg (&call_fusage, reg);
4043 /* Pass the function the address in which to return a structure value. */
4044 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
4046 emit_move_insn (struct_value_rtx,
4048 force_operand (XEXP (mem_value, 0),
4050 if (GET_CODE (struct_value_rtx) == REG)
4051 use_reg (&call_fusage, struct_value_rtx);
4054 /* Don't allow popping to be deferred, since then
4055 cse'ing of library calls could delete a call and leave the pop. */
4057 valreg = (mem_value == 0 && outmode != VOIDmode
4058 ? hard_libcall_value (outmode) : NULL_RTX);
4060 #ifdef PREFERRED_STACK_BOUNDARY
4061 /* Stack must be properly aligned now. */
4062 if (stack_pointer_delta & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1))
4066 before_call = get_last_insn ();
4068 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4069 will set inhibit_defer_pop to that value. */
4070 /* The return type is needed to decide how many bytes the function pops.
4071 Signedness plays no role in that, so for simplicity, we pretend it's
4072 always signed. We also assume that the list of arguments passed has
4073 no impact, so we pretend it is unknown. */
4076 get_identifier (XSTR (orgfun, 0)),
4077 build_function_type (outmode == VOIDmode ? void_type_node
4078 : type_for_mode (outmode, 0), NULL_TREE),
4079 original_args_size.constant, args_size.constant,
4081 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
4083 old_inhibit_defer_pop + 1, call_fusage, flags);
4085 /* For calls to `setjmp', etc., inform flow.c it should complain
4086 if nonvolatile values are live. For functions that cannot return,
4087 inform flow that control does not fall through. */
4089 if (flags & (ECF_RETURNS_TWICE | ECF_NORETURN | ECF_LONGJMP))
4091 /* The barrier or NOTE_INSN_SETJMP note must be emitted
4092 immediately after the CALL_INSN. Some ports emit more than
4093 just a CALL_INSN above, so we must search for it here. */
4095 rtx last = get_last_insn ();
4096 while (GET_CODE (last) != CALL_INSN)
4098 last = PREV_INSN (last);
4099 /* There was no CALL_INSN? */
4100 if (last == before_call)
4104 if (flags & ECF_RETURNS_TWICE)
4106 emit_note_after (NOTE_INSN_SETJMP, last);
4107 current_function_calls_setjmp = 1;
4110 emit_barrier_after (last);
4113 /* Now restore inhibit_defer_pop to its actual original value. */
4116 /* If call is cse'able, make appropriate pair of reg-notes around it.
4117 Test valreg so we don't crash; may safely ignore `const'
4118 if return type is void. Disable for PARALLEL return values, because
4119 we have no way to move such values into a pseudo register. */
4120 if ((flags & (ECF_CONST | ECF_PURE))
4121 && valreg != 0 && GET_CODE (valreg) != PARALLEL)
4124 rtx temp = gen_reg_rtx (GET_MODE (valreg));
4128 /* Construct an "equal form" for the value which mentions all the
4129 arguments in order as well as the function name. */
4130 for (i = 0; i < nargs; i++)
4131 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
4132 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
4134 insns = get_insns ();
4137 if (flags & ECF_PURE)
4138 note = gen_rtx_EXPR_LIST (VOIDmode,
4139 gen_rtx_USE (VOIDmode,
4140 gen_rtx_MEM (BLKmode,
4141 gen_rtx_SCRATCH (VOIDmode))), note);
4143 emit_libcall_block (insns, temp, valreg, note);
4147 else if (flags & (ECF_CONST | ECF_PURE))
4149 /* Otherwise, just write out the sequence without a note. */
4150 rtx insns = get_insns ();
4157 /* Copy the value to the right place. */
4158 if (outmode != VOIDmode && retval)
4164 if (value != mem_value)
4165 emit_move_insn (value, mem_value);
4167 else if (value != 0)
4168 emit_move_insn (value, hard_libcall_value (outmode));
4170 value = hard_libcall_value (outmode);
4173 if (ACCUMULATE_OUTGOING_ARGS)
4175 #ifdef REG_PARM_STACK_SPACE
4178 enum machine_mode save_mode = GET_MODE (save_area);
4179 #ifdef ARGS_GROW_DOWNWARD
4181 = gen_rtx_MEM (save_mode,
4182 memory_address (save_mode,
4183 plus_constant (argblock,
4187 = gen_rtx_MEM (save_mode,
4188 memory_address (save_mode,
4189 plus_constant (argblock, low_to_save)));
4191 if (save_mode != BLKmode)
4192 emit_move_insn (stack_area, save_area);
4194 emit_block_move (stack_area, validize_mem (save_area),
4195 GEN_INT (high_to_save - low_to_save + 1),
4200 /* If we saved any argument areas, restore them. */
4201 for (count = 0; count < nargs; count++)
4202 if (argvec[count].save_area)
4204 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4206 = gen_rtx_MEM (save_mode,
4209 plus_constant (argblock,
4210 argvec[count].offset.constant)));
4212 emit_move_insn (stack_area, argvec[count].save_area);
4215 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4216 stack_usage_map = initial_stack_usage_map;
4223 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4224 (emitting the queue unless NO_QUEUE is nonzero),
4225 for a value of mode OUTMODE,
4226 with NARGS different arguments, passed as alternating rtx values
4227 and machine_modes to convert them to.
4228 The rtx values should have been passed through protect_from_queue already.
4230 FN_TYPE will is zero for `normal' calls, one for `const' calls, wich
4231 which will be enclosed in REG_LIBCALL/REG_RETVAL notes and two for `pure'
4232 calls, that are handled like `const' calls with extra
4233 (use (memory (scratch)). */
4236 emit_library_call VPARAMS((rtx orgfun, enum libcall_type fn_type,
4237 enum machine_mode outmode, int nargs, ...))
4239 #ifndef ANSI_PROTOTYPES
4242 enum machine_mode outmode;
4247 VA_START (p, nargs);
4249 #ifndef ANSI_PROTOTYPES
4250 orgfun = va_arg (p, rtx);
4251 fn_type = va_arg (p, int);
4252 outmode = va_arg (p, enum machine_mode);
4253 nargs = va_arg (p, int);
4256 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4261 /* Like emit_library_call except that an extra argument, VALUE,
4262 comes second and says where to store the result.
4263 (If VALUE is zero, this function chooses a convenient way
4264 to return the value.
4266 This function returns an rtx for where the value is to be found.
4267 If VALUE is nonzero, VALUE is returned. */
4270 emit_library_call_value VPARAMS((rtx orgfun, rtx value,
4271 enum libcall_type fn_type,
4272 enum machine_mode outmode, int nargs, ...))
4274 #ifndef ANSI_PROTOTYPES
4278 enum machine_mode outmode;
4283 VA_START (p, nargs);
4285 #ifndef ANSI_PROTOTYPES
4286 orgfun = va_arg (p, rtx);
4287 value = va_arg (p, rtx);
4288 fn_type = va_arg (p, int);
4289 outmode = va_arg (p, enum machine_mode);
4290 nargs = va_arg (p, int);
4293 value = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode, nargs, p);
4301 /* Return an rtx which represents a suitable home on the stack
4302 given TYPE, the type of the argument looking for a home.
4303 This is called only for BLKmode arguments.
4305 SIZE is the size needed for this target.
4306 ARGS_ADDR is the address of the bottom of the argument block for this call.
4307 OFFSET describes this parameter's offset into ARGS_ADDR. It is meaningless
4308 if this machine uses push insns. */
4311 target_for_arg (type, size, args_addr, offset)
4315 struct args_size offset;
4318 rtx offset_rtx = ARGS_SIZE_RTX (offset);
4320 /* We do not call memory_address if possible,
4321 because we want to address as close to the stack
4322 as possible. For non-variable sized arguments,
4323 this will be stack-pointer relative addressing. */
4324 if (GET_CODE (offset_rtx) == CONST_INT)
4325 target = plus_constant (args_addr, INTVAL (offset_rtx));
4328 /* I have no idea how to guarantee that this
4329 will work in the presence of register parameters. */
4330 target = gen_rtx_PLUS (Pmode, args_addr, offset_rtx);
4331 target = memory_address (QImode, target);
4334 return gen_rtx_MEM (BLKmode, target);
4338 /* Store a single argument for a function call
4339 into the register or memory area where it must be passed.
4340 *ARG describes the argument value and where to pass it.
4342 ARGBLOCK is the address of the stack-block for all the arguments,
4343 or 0 on a machine where arguments are pushed individually.
4345 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4346 so must be careful about how the stack is used.
4348 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4349 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4350 that we need not worry about saving and restoring the stack.
4352 FNDECL is the declaration of the function we are calling.
4354 Return non-zero if this arg should cause sibcall failure,
4358 store_one_arg (arg, argblock, flags, variable_size, reg_parm_stack_space)
4359 struct arg_data *arg;
4362 int variable_size ATTRIBUTE_UNUSED;
4363 int reg_parm_stack_space;
4365 register tree pval = arg->tree_value;
4369 int i, lower_bound = 0, upper_bound = 0;
4370 int sibcall_failure = 0;
4372 if (TREE_CODE (pval) == ERROR_MARK)
4375 /* Push a new temporary level for any temporaries we make for
4379 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4381 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4382 save any previous data at that location. */
4383 if (argblock && ! variable_size && arg->stack)
4385 #ifdef ARGS_GROW_DOWNWARD
4386 /* stack_slot is negative, but we want to index stack_usage_map
4387 with positive values. */
4388 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4389 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4393 lower_bound = upper_bound - arg->size.constant;
4395 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4396 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4400 upper_bound = lower_bound + arg->size.constant;
4403 for (i = lower_bound; i < upper_bound; i++)
4404 if (stack_usage_map[i]
4405 /* Don't store things in the fixed argument area at this point;
4406 it has already been saved. */
4407 && i > reg_parm_stack_space)
4410 if (i != upper_bound)
4412 /* We need to make a save area. See what mode we can make it. */
4413 enum machine_mode save_mode
4414 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
4416 = gen_rtx_MEM (save_mode,
4417 memory_address (save_mode,
4418 XEXP (arg->stack_slot, 0)));
4420 if (save_mode == BLKmode)
4422 tree ot = TREE_TYPE (arg->tree_value);
4423 tree nt = build_qualified_type (ot, (TYPE_QUALS (ot)
4424 | TYPE_QUAL_CONST));
4426 arg->save_area = assign_temp (nt, 0, 1, 1);
4427 preserve_temp_slots (arg->save_area);
4428 emit_block_move (validize_mem (arg->save_area), stack_area,
4429 expr_size (arg->tree_value),
4430 MIN (PARM_BOUNDARY, TYPE_ALIGN (nt)));
4434 arg->save_area = gen_reg_rtx (save_mode);
4435 emit_move_insn (arg->save_area, stack_area);
4439 /* Now that we have saved any slots that will be overwritten by this
4440 store, mark all slots this store will use. We must do this before
4441 we actually expand the argument since the expansion itself may
4442 trigger library calls which might need to use the same stack slot. */
4443 if (argblock && ! variable_size && arg->stack)
4444 for (i = lower_bound; i < upper_bound; i++)
4445 stack_usage_map[i] = 1;
4448 /* If this isn't going to be placed on both the stack and in registers,
4449 set up the register and number of words. */
4450 if (! arg->pass_on_stack)
4451 reg = arg->reg, partial = arg->partial;
4453 if (reg != 0 && partial == 0)
4454 /* Being passed entirely in a register. We shouldn't be called in
4458 /* If this arg needs special alignment, don't load the registers
4460 if (arg->n_aligned_regs != 0)
4463 /* If this is being passed partially in a register, we can't evaluate
4464 it directly into its stack slot. Otherwise, we can. */
4465 if (arg->value == 0)
4467 /* stack_arg_under_construction is nonzero if a function argument is
4468 being evaluated directly into the outgoing argument list and
4469 expand_call must take special action to preserve the argument list
4470 if it is called recursively.
4472 For scalar function arguments stack_usage_map is sufficient to
4473 determine which stack slots must be saved and restored. Scalar
4474 arguments in general have pass_on_stack == 0.
4476 If this argument is initialized by a function which takes the
4477 address of the argument (a C++ constructor or a C function
4478 returning a BLKmode structure), then stack_usage_map is
4479 insufficient and expand_call must push the stack around the
4480 function call. Such arguments have pass_on_stack == 1.
4482 Note that it is always safe to set stack_arg_under_construction,
4483 but this generates suboptimal code if set when not needed. */
4485 if (arg->pass_on_stack)
4486 stack_arg_under_construction++;
4488 arg->value = expand_expr (pval,
4490 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4491 ? NULL_RTX : arg->stack,
4494 /* If we are promoting object (or for any other reason) the mode
4495 doesn't agree, convert the mode. */
4497 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4498 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4499 arg->value, arg->unsignedp);
4501 if (arg->pass_on_stack)
4502 stack_arg_under_construction--;
4505 /* Don't allow anything left on stack from computation
4506 of argument to alloca. */
4507 if (flags & ECF_MAY_BE_ALLOCA)
4508 do_pending_stack_adjust ();
4510 if (arg->value == arg->stack)
4512 /* If the value is already in the stack slot, we are done. */
4513 if (current_function_check_memory_usage && GET_CODE (arg->stack) == MEM)
4515 emit_library_call (chkr_set_right_libfunc, LCT_CONST_MAKE_BLOCK,
4516 VOIDmode, 3, XEXP (arg->stack, 0), Pmode,
4517 ARGS_SIZE_RTX (arg->size),
4518 TYPE_MODE (sizetype),
4519 GEN_INT (MEMORY_USE_RW),
4520 TYPE_MODE (integer_type_node));
4523 else if (arg->mode != BLKmode)
4527 /* Argument is a scalar, not entirely passed in registers.
4528 (If part is passed in registers, arg->partial says how much
4529 and emit_push_insn will take care of putting it there.)
4531 Push it, and if its size is less than the
4532 amount of space allocated to it,
4533 also bump stack pointer by the additional space.
4534 Note that in C the default argument promotions
4535 will prevent such mismatches. */
4537 size = GET_MODE_SIZE (arg->mode);
4538 /* Compute how much space the push instruction will push.
4539 On many machines, pushing a byte will advance the stack
4540 pointer by a halfword. */
4541 #ifdef PUSH_ROUNDING
4542 size = PUSH_ROUNDING (size);
4546 /* Compute how much space the argument should get:
4547 round up to a multiple of the alignment for arguments. */
4548 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4549 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4550 / (PARM_BOUNDARY / BITS_PER_UNIT))
4551 * (PARM_BOUNDARY / BITS_PER_UNIT));
4553 /* This isn't already where we want it on the stack, so put it there.
4554 This can either be done with push or copy insns. */
4555 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX, 0,
4556 partial, reg, used - size, argblock,
4557 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
4558 ARGS_SIZE_RTX (arg->alignment_pad));
4562 /* BLKmode, at least partly to be pushed. */
4564 register int excess;
4567 /* Pushing a nonscalar.
4568 If part is passed in registers, PARTIAL says how much
4569 and emit_push_insn will take care of putting it there. */
4571 /* Round its size up to a multiple
4572 of the allocation unit for arguments. */
4574 if (arg->size.var != 0)
4577 size_rtx = ARGS_SIZE_RTX (arg->size);
4581 /* PUSH_ROUNDING has no effect on us, because
4582 emit_push_insn for BLKmode is careful to avoid it. */
4583 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
4584 + partial * UNITS_PER_WORD);
4585 size_rtx = expr_size (pval);
4588 if ((flags & ECF_SIBCALL) && GET_CODE (arg->value) == MEM)
4590 /* emit_push_insn might not work properly if arg->value and
4591 argblock + arg->offset areas overlap. */
4595 if (XEXP (x, 0) == current_function_internal_arg_pointer
4596 || (GET_CODE (XEXP (x, 0)) == PLUS
4597 && XEXP (XEXP (x, 0), 0) ==
4598 current_function_internal_arg_pointer
4599 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT))
4601 if (XEXP (x, 0) != current_function_internal_arg_pointer)
4602 i = INTVAL (XEXP (XEXP (x, 0), 1));
4604 /* expand_call should ensure this */
4605 if (arg->offset.var || GET_CODE (size_rtx) != CONST_INT)
4608 if (arg->offset.constant > i)
4610 if (arg->offset.constant < i + INTVAL (size_rtx))
4611 sibcall_failure = 1;
4613 else if (arg->offset.constant < i)
4615 if (i < arg->offset.constant + INTVAL (size_rtx))
4616 sibcall_failure = 1;
4621 /* If parm is passed both in stack and in register and offset is
4622 greater than reg_parm_stack_space, split the offset. */
4623 if (arg->reg && arg->pass_on_stack)
4625 if (arg->offset.constant < reg_parm_stack_space && arg->offset.var)
4626 error ("variable offset is passed paritially in stack and in reg");
4627 else if (arg->offset.constant < reg_parm_stack_space && arg->size.var)
4628 error ("variable size is passed partially in stack and in reg");
4629 else if (arg->offset.constant < reg_parm_stack_space
4630 && ((arg->offset.constant + arg->size.constant)
4631 > reg_parm_stack_space))
4633 rtx size_rtx1 = GEN_INT (reg_parm_stack_space - arg->offset.constant);
4634 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx1,
4635 TYPE_ALIGN (TREE_TYPE (pval)), partial, reg,
4636 excess, argblock, ARGS_SIZE_RTX (arg->offset),
4637 reg_parm_stack_space,
4638 ARGS_SIZE_RTX (arg->alignment_pad));
4640 size_rtx = GEN_INT (INTVAL(size_rtx) - reg_parm_stack_space);
4645 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4646 TYPE_ALIGN (TREE_TYPE (pval)), partial, reg, excess,
4647 argblock, ARGS_SIZE_RTX (arg->offset),
4648 reg_parm_stack_space,
4649 ARGS_SIZE_RTX (arg->alignment_pad));
4652 /* Unless this is a partially-in-register argument, the argument is now
4655 ??? Note that this can change arg->value from arg->stack to
4656 arg->stack_slot and it matters when they are not the same.
4657 It isn't totally clear that this is correct in all cases. */
4659 arg->value = arg->stack_slot;
4661 /* Once we have pushed something, pops can't safely
4662 be deferred during the rest of the arguments. */
4665 /* ANSI doesn't require a sequence point here,
4666 but PCC has one, so this will avoid some problems. */
4669 /* Free any temporary slots made in processing this argument. Show
4670 that we might have taken the address of something and pushed that
4672 preserve_temp_slots (NULL_RTX);
4676 return sibcall_failure;