1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998
3 1999, 2000, 2001 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
37 #if !defined FUNCTION_OK_FOR_SIBCALL
38 #define FUNCTION_OK_FOR_SIBCALL(DECL) 1
41 /* Decide whether a function's arguments should be processed
42 from first to last or from last to first.
44 They should if the stack and args grow in opposite directions, but
45 only if we have push insns. */
49 #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
50 #define PUSH_ARGS_REVERSED PUSH_ARGS
55 #ifndef PUSH_ARGS_REVERSED
56 #define PUSH_ARGS_REVERSED 0
59 #ifndef STACK_POINTER_OFFSET
60 #define STACK_POINTER_OFFSET 0
63 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
64 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
66 /* Data structure and subroutines used within expand_call. */
70 /* Tree node for this argument. */
72 /* Mode for value; TYPE_MODE unless promoted. */
73 enum machine_mode mode;
74 /* Current RTL value for argument, or 0 if it isn't precomputed. */
76 /* Initially-compute RTL value for argument; only for const functions. */
78 /* Register to pass this argument in, 0 if passed on stack, or an
79 PARALLEL if the arg is to be copied into multiple non-contiguous
82 /* Register to pass this argument in when generating tail call sequence.
83 This is not the same register as for normal calls on machines with
86 /* If REG was promoted from the actual mode of the argument expression,
87 indicates whether the promotion is sign- or zero-extended. */
89 /* Number of registers to use. 0 means put the whole arg in registers.
90 Also 0 if not passed in registers. */
92 /* Non-zero if argument must be passed on stack.
93 Note that some arguments may be passed on the stack
94 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
95 pass_on_stack identifies arguments that *cannot* go in registers. */
97 /* Offset of this argument from beginning of stack-args. */
98 struct args_size offset;
99 /* Similar, but offset to the start of the stack slot. Different from
100 OFFSET if this arg pads downward. */
101 struct args_size slot_offset;
102 /* Size of this argument on the stack, rounded up for any padding it gets,
103 parts of the argument passed in registers do not count.
104 If REG_PARM_STACK_SPACE is defined, then register parms
105 are counted here as well. */
106 struct args_size size;
107 /* Location on the stack at which parameter should be stored. The store
108 has already been done if STACK == VALUE. */
110 /* Location on the stack of the start of this argument slot. This can
111 differ from STACK if this arg pads downward. This location is known
112 to be aligned to FUNCTION_ARG_BOUNDARY. */
114 /* Place that this stack area has been saved, if needed. */
116 /* If an argument's alignment does not permit direct copying into registers,
117 copy in smaller-sized pieces into pseudos. These are stored in a
118 block pointed to by this field. The next field says how many
119 word-sized pseudos we made. */
122 /* The amount that the stack pointer needs to be adjusted to
123 force alignment for the next argument. */
124 struct args_size alignment_pad;
127 /* A vector of one char per byte of stack space. A byte if non-zero if
128 the corresponding stack location has been used.
129 This vector is used to prevent a function call within an argument from
130 clobbering any stack already set up. */
131 static char *stack_usage_map;
133 /* Size of STACK_USAGE_MAP. */
134 static int highest_outgoing_arg_in_use;
136 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
137 stack location's tail call argument has been already stored into the stack.
138 This bitmap is used to prevent sibling call optimization if function tries
139 to use parent's incoming argument slots when they have been already
140 overwritten with tail call arguments. */
141 static sbitmap stored_args_map;
143 /* stack_arg_under_construction is nonzero when an argument may be
144 initialized with a constructor call (including a C function that
145 returns a BLKmode struct) and expand_call must take special action
146 to make sure the object being constructed does not overlap the
147 argument list for the constructor call. */
148 int stack_arg_under_construction;
150 static int calls_function PARAMS ((tree, int));
151 static int calls_function_1 PARAMS ((tree, int));
153 /* Nonzero if this is a call to a `const' function. */
155 /* Nonzero if this is a call to a `volatile' function. */
156 #define ECF_NORETURN 2
157 /* Nonzero if this is a call to malloc or a related function. */
159 /* Nonzero if it is plausible that this is a call to alloca. */
160 #define ECF_MAY_BE_ALLOCA 8
161 /* Nonzero if this is a call to a function that won't throw an exception. */
162 #define ECF_NOTHROW 16
163 /* Nonzero if this is a call to setjmp or a related function. */
164 #define ECF_RETURNS_TWICE 32
165 /* Nonzero if this is a call to `longjmp'. */
166 #define ECF_LONGJMP 64
167 /* Nonzero if this is a syscall that makes a new process in the image of
169 #define ECF_FORK_OR_EXEC 128
170 #define ECF_SIBCALL 256
171 /* Nonzero if this is a call to "pure" function (like const function,
172 but may read memory. */
174 /* Nonzero if this is a call to a function that returns with the stack
175 pointer depressed. */
176 #define ECF_SP_DEPRESSED 1024
177 /* Nonzero if this call is known to always return. */
178 #define ECF_ALWAYS_RETURN 2048
180 static void emit_call_1 PARAMS ((rtx, tree, tree, HOST_WIDE_INT,
181 HOST_WIDE_INT, HOST_WIDE_INT, rtx,
182 rtx, int, rtx, int));
183 static void precompute_register_parameters PARAMS ((int,
186 static int store_one_arg PARAMS ((struct arg_data *, rtx, int, int,
188 static void store_unaligned_arguments_into_pseudos PARAMS ((struct arg_data *,
190 static int finalize_must_preallocate PARAMS ((int, int,
192 struct args_size *));
193 static void precompute_arguments PARAMS ((int, int,
195 static int compute_argument_block_size PARAMS ((int,
198 static void initialize_argument_information PARAMS ((int,
205 static void compute_argument_addresses PARAMS ((struct arg_data *,
207 static rtx rtx_for_function_call PARAMS ((tree, tree));
208 static void load_register_parameters PARAMS ((struct arg_data *,
210 static rtx emit_library_call_value_1 PARAMS ((int, rtx, rtx,
214 static int special_function_p PARAMS ((tree, int));
215 static int flags_from_decl_or_type PARAMS ((tree));
216 static rtx try_to_integrate PARAMS ((tree, tree, rtx,
218 static int check_sibcall_argument_overlap_1 PARAMS ((rtx));
219 static int check_sibcall_argument_overlap PARAMS ((rtx, struct arg_data *));
221 static int combine_pending_stack_adjustment_and_call
222 PARAMS ((int, struct args_size *, int));
224 #ifdef REG_PARM_STACK_SPACE
225 static rtx save_fixed_argument_area PARAMS ((int, rtx, int *, int *));
226 static void restore_fixed_argument_area PARAMS ((rtx, rtx, int, int));
229 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
232 If WHICH is 0, return 1 if EXP contains a call to any function.
233 Actually, we only need return 1 if evaluating EXP would require pushing
234 arguments on the stack, but that is too difficult to compute, so we just
235 assume any function call might require the stack. */
237 static tree calls_function_save_exprs;
240 calls_function (exp, which)
246 calls_function_save_exprs = 0;
247 val = calls_function_1 (exp, which);
248 calls_function_save_exprs = 0;
252 /* Recursive function to do the work of above function. */
255 calls_function_1 (exp, which)
260 enum tree_code code = TREE_CODE (exp);
261 int class = TREE_CODE_CLASS (code);
262 int length = first_rtl_op (code);
264 /* If this code is language-specific, we don't know what it will do. */
265 if ((int) code >= NUM_TREE_CODES)
273 else if ((TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))
275 && (TYPE_RETURNS_STACK_DEPRESSED
276 (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))))
278 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
279 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
281 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
283 & ECF_MAY_BE_ALLOCA))
292 for (tem = CONSTRUCTOR_ELTS (exp); tem != 0; tem = TREE_CHAIN (tem))
293 if (calls_function_1 (TREE_VALUE (tem), which))
300 if (SAVE_EXPR_RTL (exp) != 0)
302 if (value_member (exp, calls_function_save_exprs))
304 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
305 calls_function_save_exprs);
306 return (TREE_OPERAND (exp, 0) != 0
307 && calls_function_1 (TREE_OPERAND (exp, 0), which));
314 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
315 if (DECL_INITIAL (local) != 0
316 && calls_function_1 (DECL_INITIAL (local), which))
319 for (subblock = BLOCK_SUBBLOCKS (exp);
321 subblock = TREE_CHAIN (subblock))
322 if (calls_function_1 (subblock, which))
328 for (; exp != 0; exp = TREE_CHAIN (exp))
329 if (calls_function_1 (TREE_VALUE (exp), which))
337 /* Only expressions, references, and blocks can contain calls. */
338 if (! IS_EXPR_CODE_CLASS (class) && class != 'r' && class != 'b')
341 for (i = 0; i < length; i++)
342 if (TREE_OPERAND (exp, i) != 0
343 && calls_function_1 (TREE_OPERAND (exp, i), which))
349 /* Force FUNEXP into a form suitable for the address of a CALL,
350 and return that as an rtx. Also load the static chain register
351 if FNDECL is a nested function.
353 CALL_FUSAGE points to a variable holding the prospective
354 CALL_INSN_FUNCTION_USAGE information. */
357 prepare_call_address (funexp, fndecl, call_fusage, reg_parm_seen, sibcallp)
364 rtx static_chain_value = 0;
366 funexp = protect_from_queue (funexp, 0);
369 /* Get possible static chain value for nested function in C. */
370 static_chain_value = lookup_static_chain (fndecl);
372 /* Make a valid memory address and copy constants thru pseudo-regs,
373 but not for a constant address if -fno-function-cse. */
374 if (GET_CODE (funexp) != SYMBOL_REF)
375 /* If we are using registers for parameters, force the
376 function address into a register now. */
377 funexp = ((SMALL_REGISTER_CLASSES && reg_parm_seen)
378 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
379 : memory_address (FUNCTION_MODE, funexp));
382 #ifndef NO_FUNCTION_CSE
383 if (optimize && ! flag_no_function_cse)
384 #ifdef NO_RECURSIVE_FUNCTION_CSE
385 if (fndecl != current_function_decl)
387 funexp = force_reg (Pmode, funexp);
391 if (static_chain_value != 0)
393 emit_move_insn (static_chain_rtx, static_chain_value);
395 if (GET_CODE (static_chain_rtx) == REG)
396 use_reg (call_fusage, static_chain_rtx);
402 /* Generate instructions to call function FUNEXP,
403 and optionally pop the results.
404 The CALL_INSN is the first insn generated.
406 FNDECL is the declaration node of the function. This is given to the
407 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
409 FUNTYPE is the data type of the function. This is given to the macro
410 RETURN_POPS_ARGS to determine whether this function pops its own args.
411 We used to allow an identifier for library functions, but that doesn't
412 work when the return type is an aggregate type and the calling convention
413 says that the pointer to this aggregate is to be popped by the callee.
415 STACK_SIZE is the number of bytes of arguments on the stack,
416 ROUNDED_STACK_SIZE is that number rounded up to
417 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
418 both to put into the call insn and to generate explicit popping
421 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
422 It is zero if this call doesn't want a structure value.
424 NEXT_ARG_REG is the rtx that results from executing
425 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
426 just after all the args have had their registers assigned.
427 This could be whatever you like, but normally it is the first
428 arg-register beyond those used for args in this call,
429 or 0 if all the arg-registers are used in this call.
430 It is passed on to `gen_call' so you can put this info in the call insn.
432 VALREG is a hard register in which a value is returned,
433 or 0 if the call does not return a value.
435 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
436 the args to this call were processed.
437 We restore `inhibit_defer_pop' to that value.
439 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
440 denote registers used by the called function. */
443 emit_call_1 (funexp, fndecl, funtype, stack_size, rounded_stack_size,
444 struct_value_size, next_arg_reg, valreg, old_inhibit_defer_pop,
445 call_fusage, ecf_flags)
447 tree fndecl ATTRIBUTE_UNUSED;
448 tree funtype ATTRIBUTE_UNUSED;
449 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED;
450 HOST_WIDE_INT rounded_stack_size;
451 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED;
452 rtx next_arg_reg ATTRIBUTE_UNUSED;
454 int old_inhibit_defer_pop;
458 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
460 int already_popped = 0;
461 HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
462 #if defined (HAVE_call) && defined (HAVE_call_value)
463 rtx struct_value_size_rtx;
464 struct_value_size_rtx = GEN_INT (struct_value_size);
467 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
468 and we don't want to load it into a register as an optimization,
469 because prepare_call_address already did it if it should be done. */
470 if (GET_CODE (funexp) != SYMBOL_REF)
471 funexp = memory_address (FUNCTION_MODE, funexp);
473 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
474 if ((ecf_flags & ECF_SIBCALL)
475 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
476 && (n_popped > 0 || stack_size == 0))
478 rtx n_pop = GEN_INT (n_popped);
481 /* If this subroutine pops its own args, record that in the call insn
482 if possible, for the sake of frame pointer elimination. */
485 pat = GEN_SIBCALL_VALUE_POP (valreg,
486 gen_rtx_MEM (FUNCTION_MODE, funexp),
487 rounded_stack_size_rtx, next_arg_reg,
490 pat = GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
491 rounded_stack_size_rtx, next_arg_reg, n_pop);
493 emit_call_insn (pat);
499 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
500 /* If the target has "call" or "call_value" insns, then prefer them
501 if no arguments are actually popped. If the target does not have
502 "call" or "call_value" insns, then we must use the popping versions
503 even if the call has no arguments to pop. */
504 #if defined (HAVE_call) && defined (HAVE_call_value)
505 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
506 && n_popped > 0 && ! (ecf_flags & ECF_SP_DEPRESSED))
508 if (HAVE_call_pop && HAVE_call_value_pop)
511 rtx n_pop = GEN_INT (n_popped);
514 /* If this subroutine pops its own args, record that in the call insn
515 if possible, for the sake of frame pointer elimination. */
518 pat = GEN_CALL_VALUE_POP (valreg,
519 gen_rtx_MEM (FUNCTION_MODE, funexp),
520 rounded_stack_size_rtx, next_arg_reg, n_pop);
522 pat = GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
523 rounded_stack_size_rtx, next_arg_reg, n_pop);
525 emit_call_insn (pat);
531 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
532 if ((ecf_flags & ECF_SIBCALL)
533 && HAVE_sibcall && HAVE_sibcall_value)
536 emit_call_insn (GEN_SIBCALL_VALUE (valreg,
537 gen_rtx_MEM (FUNCTION_MODE, funexp),
538 rounded_stack_size_rtx,
539 next_arg_reg, NULL_RTX));
541 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
542 rounded_stack_size_rtx, next_arg_reg,
543 struct_value_size_rtx));
548 #if defined (HAVE_call) && defined (HAVE_call_value)
549 if (HAVE_call && HAVE_call_value)
552 emit_call_insn (GEN_CALL_VALUE (valreg,
553 gen_rtx_MEM (FUNCTION_MODE, funexp),
554 rounded_stack_size_rtx, next_arg_reg,
557 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
558 rounded_stack_size_rtx, next_arg_reg,
559 struct_value_size_rtx));
565 /* Find the CALL insn we just emitted. */
566 for (call_insn = get_last_insn ();
567 call_insn && GET_CODE (call_insn) != CALL_INSN;
568 call_insn = PREV_INSN (call_insn))
574 /* Mark memory as used for "pure" function call. */
575 if (ecf_flags & ECF_PURE)
579 gen_rtx_USE (VOIDmode,
580 gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (VOIDmode))),
583 /* Put the register usage information on the CALL. If there is already
584 some usage information, put ours at the end. */
585 if (CALL_INSN_FUNCTION_USAGE (call_insn))
589 for (link = CALL_INSN_FUNCTION_USAGE (call_insn); XEXP (link, 1) != 0;
590 link = XEXP (link, 1))
593 XEXP (link, 1) = call_fusage;
596 CALL_INSN_FUNCTION_USAGE (call_insn) = call_fusage;
598 /* If this is a const call, then set the insn's unchanging bit. */
599 if (ecf_flags & (ECF_CONST | ECF_PURE))
600 CONST_OR_PURE_CALL_P (call_insn) = 1;
602 /* If this call can't throw, attach a REG_EH_REGION reg note to that
604 if (ecf_flags & ECF_NOTHROW)
605 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_EH_REGION, const0_rtx,
606 REG_NOTES (call_insn));
608 if (ecf_flags & ECF_NORETURN)
609 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_NORETURN, const0_rtx,
610 REG_NOTES (call_insn));
611 if (ecf_flags & ECF_ALWAYS_RETURN)
612 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_ALWAYS_RETURN, const0_rtx,
613 REG_NOTES (call_insn));
615 if (ecf_flags & ECF_RETURNS_TWICE)
617 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_SETJMP, const0_rtx,
618 REG_NOTES (call_insn));
619 current_function_calls_setjmp = 1;
622 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
624 /* Restore this now, so that we do defer pops for this call's args
625 if the context of the call as a whole permits. */
626 inhibit_defer_pop = old_inhibit_defer_pop;
631 CALL_INSN_FUNCTION_USAGE (call_insn)
632 = gen_rtx_EXPR_LIST (VOIDmode,
633 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
634 CALL_INSN_FUNCTION_USAGE (call_insn));
635 rounded_stack_size -= n_popped;
636 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
637 stack_pointer_delta -= n_popped;
640 if (!ACCUMULATE_OUTGOING_ARGS)
642 /* If returning from the subroutine does not automatically pop the args,
643 we need an instruction to pop them sooner or later.
644 Perhaps do it now; perhaps just record how much space to pop later.
646 If returning from the subroutine does pop the args, indicate that the
647 stack pointer will be changed. */
649 if (rounded_stack_size != 0)
651 if (ecf_flags & ECF_SP_DEPRESSED)
652 /* Just pretend we did the pop. */
653 stack_pointer_delta -= rounded_stack_size;
654 else if (flag_defer_pop && inhibit_defer_pop == 0
655 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
656 pending_stack_adjust += rounded_stack_size;
658 adjust_stack (rounded_stack_size_rtx);
661 /* When we accumulate outgoing args, we must avoid any stack manipulations.
662 Restore the stack pointer to its original value now. Usually
663 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
664 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
665 popping variants of functions exist as well.
667 ??? We may optimize similar to defer_pop above, but it is
668 probably not worthwhile.
670 ??? It will be worthwhile to enable combine_stack_adjustments even for
673 anti_adjust_stack (GEN_INT (n_popped));
676 /* Determine if the function identified by NAME and FNDECL is one with
677 special properties we wish to know about.
679 For example, if the function might return more than one time (setjmp), then
680 set RETURNS_TWICE to a nonzero value.
682 Similarly set LONGJMP for if the function is in the longjmp family.
684 Set MALLOC for any of the standard memory allocation functions which
685 allocate from the heap.
687 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
688 space from the stack such as alloca. */
691 special_function_p (fndecl, flags)
695 if (! (flags & ECF_MALLOC)
696 && fndecl && DECL_NAME (fndecl)
697 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
698 /* Exclude functions not at the file scope, or not `extern',
699 since they are not the magic functions we would otherwise
701 && DECL_CONTEXT (fndecl) == NULL_TREE && TREE_PUBLIC (fndecl))
703 const char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
704 const char *tname = name;
706 /* We assume that alloca will always be called by name. It
707 makes no sense to pass it as a pointer-to-function to
708 anything that does not understand its behavior. */
709 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
711 && ! strcmp (name, "alloca"))
712 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
714 && ! strcmp (name, "__builtin_alloca"))))
715 flags |= ECF_MAY_BE_ALLOCA;
717 /* Disregard prefix _, __ or __x. */
720 if (name[1] == '_' && name[2] == 'x')
722 else if (name[1] == '_')
731 && (! strcmp (tname, "setjmp")
732 || ! strcmp (tname, "setjmp_syscall")))
734 && ! strcmp (tname, "sigsetjmp"))
736 && ! strcmp (tname, "savectx")))
737 flags |= ECF_RETURNS_TWICE;
740 && ! strcmp (tname, "siglongjmp"))
741 flags |= ECF_LONGJMP;
743 else if ((tname[0] == 'q' && tname[1] == 's'
744 && ! strcmp (tname, "qsetjmp"))
745 || (tname[0] == 'v' && tname[1] == 'f'
746 && ! strcmp (tname, "vfork")))
747 flags |= ECF_RETURNS_TWICE;
749 else if (tname[0] == 'l' && tname[1] == 'o'
750 && ! strcmp (tname, "longjmp"))
751 flags |= ECF_LONGJMP;
753 else if ((tname[0] == 'f' && tname[1] == 'o'
754 && ! strcmp (tname, "fork"))
755 /* Linux specific: __clone. check NAME to insist on the
756 leading underscores, to avoid polluting the ISO / POSIX
758 || (name[0] == '_' && name[1] == '_'
759 && ! strcmp (tname, "clone"))
760 || (tname[0] == 'e' && tname[1] == 'x' && tname[2] == 'e'
761 && tname[3] == 'c' && (tname[4] == 'l' || tname[4] == 'v')
763 || ((tname[5] == 'p' || tname[5] == 'e')
764 && tname[6] == '\0'))))
765 flags |= ECF_FORK_OR_EXEC;
767 /* Do not add any more malloc-like functions to this list,
768 instead mark them as malloc functions using the malloc attribute.
769 Note, realloc is not suitable for attribute malloc since
770 it may return the same address across multiple calls.
771 C++ operator new is not suitable because it is not required
772 to return a unique pointer; indeed, the standard placement new
773 just returns its argument. */
774 else if (TYPE_MODE (TREE_TYPE (TREE_TYPE (fndecl))) == Pmode
775 && (! strcmp (tname, "malloc")
776 || ! strcmp (tname, "calloc")
777 || ! strcmp (tname, "strdup")))
783 /* Return nonzero when tree represent call to longjmp. */
786 setjmp_call_p (fndecl)
789 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
792 /* Detect flags (function attributes) from the function type node. */
795 flags_from_decl_or_type (exp)
800 /* ??? We can't set IS_MALLOC for function types? */
803 /* The function exp may have the `malloc' attribute. */
804 if (DECL_P (exp) && DECL_IS_MALLOC (exp))
807 /* The function exp may have the `pure' attribute. */
808 if (DECL_P (exp) && DECL_IS_PURE (exp))
811 if (TREE_NOTHROW (exp))
812 flags |= ECF_NOTHROW;
815 if (TREE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
818 if (TREE_THIS_VOLATILE (exp))
819 flags |= ECF_NORETURN;
824 /* Precompute all register parameters as described by ARGS, storing values
825 into fields within the ARGS array.
827 NUM_ACTUALS indicates the total number elements in the ARGS array.
829 Set REG_PARM_SEEN if we encounter a register parameter. */
832 precompute_register_parameters (num_actuals, args, reg_parm_seen)
834 struct arg_data *args;
841 for (i = 0; i < num_actuals; i++)
842 if (args[i].reg != 0 && ! args[i].pass_on_stack)
846 if (args[i].value == 0)
849 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
851 preserve_temp_slots (args[i].value);
854 /* ANSI doesn't require a sequence point here,
855 but PCC has one, so this will avoid some problems. */
859 /* If we are to promote the function arg to a wider mode,
862 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
864 = convert_modes (args[i].mode,
865 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
866 args[i].value, args[i].unsignedp);
868 /* If the value is expensive, and we are inside an appropriately
869 short loop, put the value into a pseudo and then put the pseudo
872 For small register classes, also do this if this call uses
873 register parameters. This is to avoid reload conflicts while
874 loading the parameters registers. */
876 if ((! (GET_CODE (args[i].value) == REG
877 || (GET_CODE (args[i].value) == SUBREG
878 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
879 && args[i].mode != BLKmode
880 && rtx_cost (args[i].value, SET) > COSTS_N_INSNS (1)
881 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
882 || preserve_subexpressions_p ()))
883 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
887 #ifdef REG_PARM_STACK_SPACE
889 /* The argument list is the property of the called routine and it
890 may clobber it. If the fixed area has been used for previous
891 parameters, we must save and restore it. */
894 save_fixed_argument_area (reg_parm_stack_space, argblock,
895 low_to_save, high_to_save)
896 int reg_parm_stack_space;
902 rtx save_area = NULL_RTX;
904 /* Compute the boundary of the that needs to be saved, if any. */
905 #ifdef ARGS_GROW_DOWNWARD
906 for (i = 0; i < reg_parm_stack_space + 1; i++)
908 for (i = 0; i < reg_parm_stack_space; i++)
911 if (i >= highest_outgoing_arg_in_use
912 || stack_usage_map[i] == 0)
915 if (*low_to_save == -1)
921 if (*low_to_save >= 0)
923 int num_to_save = *high_to_save - *low_to_save + 1;
924 enum machine_mode save_mode
925 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
928 /* If we don't have the required alignment, must do this in BLKmode. */
929 if ((*low_to_save & (MIN (GET_MODE_SIZE (save_mode),
930 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
933 #ifdef ARGS_GROW_DOWNWARD
935 = gen_rtx_MEM (save_mode,
936 memory_address (save_mode,
937 plus_constant (argblock,
940 stack_area = gen_rtx_MEM (save_mode,
941 memory_address (save_mode,
942 plus_constant (argblock,
946 set_mem_align (stack_area, PARM_BOUNDARY);
947 if (save_mode == BLKmode)
949 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
950 /* Cannot use emit_block_move here because it can be done by a
951 library call which in turn gets into this place again and deadly
952 infinite recursion happens. */
953 move_by_pieces (validize_mem (save_area), stack_area, num_to_save,
958 save_area = gen_reg_rtx (save_mode);
959 emit_move_insn (save_area, stack_area);
967 restore_fixed_argument_area (save_area, argblock, high_to_save, low_to_save)
973 enum machine_mode save_mode = GET_MODE (save_area);
974 #ifdef ARGS_GROW_DOWNWARD
976 = gen_rtx_MEM (save_mode,
977 memory_address (save_mode,
978 plus_constant (argblock,
982 = gen_rtx_MEM (save_mode,
983 memory_address (save_mode,
984 plus_constant (argblock,
988 if (save_mode != BLKmode)
989 emit_move_insn (stack_area, save_area);
991 /* Cannot use emit_block_move here because it can be done by a library
992 call which in turn gets into this place again and deadly infinite
993 recursion happens. */
994 move_by_pieces (stack_area, validize_mem (save_area),
995 high_to_save - low_to_save + 1, PARM_BOUNDARY);
997 #endif /* REG_PARM_STACK_SPACE */
999 /* If any elements in ARGS refer to parameters that are to be passed in
1000 registers, but not in memory, and whose alignment does not permit a
1001 direct copy into registers. Copy the values into a group of pseudos
1002 which we will later copy into the appropriate hard registers.
1004 Pseudos for each unaligned argument will be stored into the array
1005 args[argnum].aligned_regs. The caller is responsible for deallocating
1006 the aligned_regs array if it is nonzero. */
1009 store_unaligned_arguments_into_pseudos (args, num_actuals)
1010 struct arg_data *args;
1015 for (i = 0; i < num_actuals; i++)
1016 if (args[i].reg != 0 && ! args[i].pass_on_stack
1017 && args[i].mode == BLKmode
1018 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1019 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1021 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1022 int big_endian_correction = 0;
1024 args[i].n_aligned_regs
1025 = args[i].partial ? args[i].partial
1026 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1028 args[i].aligned_regs = (rtx *) xmalloc (sizeof (rtx)
1029 * args[i].n_aligned_regs);
1031 /* Structures smaller than a word are aligned to the least
1032 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1033 this means we must skip the empty high order bytes when
1034 calculating the bit offset. */
1035 if (BYTES_BIG_ENDIAN
1036 && !FUNCTION_ARG_REG_LITTLE_ENDIAN
1037 && bytes < UNITS_PER_WORD)
1038 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1040 for (j = 0; j < args[i].n_aligned_regs; j++)
1042 rtx reg = gen_reg_rtx (word_mode);
1043 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1044 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1046 args[i].aligned_regs[j] = reg;
1048 /* There is no need to restrict this code to loading items
1049 in TYPE_ALIGN sized hunks. The bitfield instructions can
1050 load up entire word sized registers efficiently.
1052 ??? This may not be needed anymore.
1053 We use to emit a clobber here but that doesn't let later
1054 passes optimize the instructions we emit. By storing 0 into
1055 the register later passes know the first AND to zero out the
1056 bitfield being set in the register is unnecessary. The store
1057 of 0 will be deleted as will at least the first AND. */
1059 emit_move_insn (reg, const0_rtx);
1061 bytes -= bitsize / BITS_PER_UNIT;
1062 store_bit_field (reg, bitsize, big_endian_correction, word_mode,
1063 extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1064 word_mode, word_mode,
1071 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1074 NUM_ACTUALS is the total number of parameters.
1076 N_NAMED_ARGS is the total number of named arguments.
1078 FNDECL is the tree code for the target of this call (if known)
1080 ARGS_SO_FAR holds state needed by the target to know where to place
1083 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1084 for arguments which are passed in registers.
1086 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1087 and may be modified by this routine.
1089 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1090 flags which may may be modified by this routine. */
1093 initialize_argument_information (num_actuals, args, args_size, n_named_args,
1094 actparms, fndecl, args_so_far,
1095 reg_parm_stack_space, old_stack_level,
1096 old_pending_adj, must_preallocate,
1098 int num_actuals ATTRIBUTE_UNUSED;
1099 struct arg_data *args;
1100 struct args_size *args_size;
1101 int n_named_args ATTRIBUTE_UNUSED;
1104 CUMULATIVE_ARGS *args_so_far;
1105 int reg_parm_stack_space;
1106 rtx *old_stack_level;
1107 int *old_pending_adj;
1108 int *must_preallocate;
1111 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1114 /* Count arg position in order args appear. */
1117 struct args_size alignment_pad;
1121 args_size->constant = 0;
1124 /* In this loop, we consider args in the order they are written.
1125 We fill up ARGS from the front or from the back if necessary
1126 so that in any case the first arg to be pushed ends up at the front. */
1128 if (PUSH_ARGS_REVERSED)
1130 i = num_actuals - 1, inc = -1;
1131 /* In this case, must reverse order of args
1132 so that we compute and push the last arg first. */
1139 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1140 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1142 tree type = TREE_TYPE (TREE_VALUE (p));
1144 enum machine_mode mode;
1146 args[i].tree_value = TREE_VALUE (p);
1148 /* Replace erroneous argument with constant zero. */
1149 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1150 args[i].tree_value = integer_zero_node, type = integer_type_node;
1152 /* If TYPE is a transparent union, pass things the way we would
1153 pass the first field of the union. We have already verified that
1154 the modes are the same. */
1155 if (TREE_CODE (type) == UNION_TYPE && TYPE_TRANSPARENT_UNION (type))
1156 type = TREE_TYPE (TYPE_FIELDS (type));
1158 /* Decide where to pass this arg.
1160 args[i].reg is nonzero if all or part is passed in registers.
1162 args[i].partial is nonzero if part but not all is passed in registers,
1163 and the exact value says how many words are passed in registers.
1165 args[i].pass_on_stack is nonzero if the argument must at least be
1166 computed on the stack. It may then be loaded back into registers
1167 if args[i].reg is nonzero.
1169 These decisions are driven by the FUNCTION_... macros and must agree
1170 with those made by function.c. */
1172 /* See if this argument should be passed by invisible reference. */
1173 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1174 && contains_placeholder_p (TYPE_SIZE (type)))
1175 || TREE_ADDRESSABLE (type)
1176 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1177 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
1178 type, argpos < n_named_args)
1182 /* If we're compiling a thunk, pass through invisible
1183 references instead of making a copy. */
1184 if (current_function_is_thunk
1185 #ifdef FUNCTION_ARG_CALLEE_COPIES
1186 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
1187 type, argpos < n_named_args)
1188 /* If it's in a register, we must make a copy of it too. */
1189 /* ??? Is this a sufficient test? Is there a better one? */
1190 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1191 && REG_P (DECL_RTL (args[i].tree_value)))
1192 && ! TREE_ADDRESSABLE (type))
1196 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1197 new object from the argument. If we are passing by
1198 invisible reference, the callee will do that for us, so we
1199 can strip off the TARGET_EXPR. This is not always safe,
1200 but it is safe in the only case where this is a useful
1201 optimization; namely, when the argument is a plain object.
1202 In that case, the frontend is just asking the backend to
1203 make a bitwise copy of the argument. */
1205 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
1206 && (DECL_P (TREE_OPERAND (args[i].tree_value, 1)))
1207 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
1208 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
1210 args[i].tree_value = build1 (ADDR_EXPR,
1211 build_pointer_type (type),
1212 args[i].tree_value);
1213 type = build_pointer_type (type);
1215 else if (TREE_CODE (args[i].tree_value) == TARGET_EXPR)
1217 /* In the V3 C++ ABI, parameters are destroyed in the caller.
1218 We implement this by passing the address of the temporary
1219 rather than expanding it into another allocated slot. */
1220 args[i].tree_value = build1 (ADDR_EXPR,
1221 build_pointer_type (type),
1222 args[i].tree_value);
1223 type = build_pointer_type (type);
1227 /* We make a copy of the object and pass the address to the
1228 function being called. */
1231 if (!COMPLETE_TYPE_P (type)
1232 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1233 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1234 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1235 STACK_CHECK_MAX_VAR_SIZE))))
1237 /* This is a variable-sized object. Make space on the stack
1239 rtx size_rtx = expr_size (TREE_VALUE (p));
1241 if (*old_stack_level == 0)
1243 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1244 *old_pending_adj = pending_stack_adjust;
1245 pending_stack_adjust = 0;
1248 copy = gen_rtx_MEM (BLKmode,
1249 allocate_dynamic_stack_space
1250 (size_rtx, NULL_RTX, TYPE_ALIGN (type)));
1251 set_mem_attributes (copy, type, 1);
1254 copy = assign_temp (type, 0, 1, 0);
1256 store_expr (args[i].tree_value, copy, 0);
1257 *ecf_flags &= ~(ECF_CONST | ECF_PURE);
1259 args[i].tree_value = build1 (ADDR_EXPR,
1260 build_pointer_type (type),
1261 make_tree (type, copy));
1262 type = build_pointer_type (type);
1266 mode = TYPE_MODE (type);
1267 unsignedp = TREE_UNSIGNED (type);
1269 #ifdef PROMOTE_FUNCTION_ARGS
1270 mode = promote_mode (type, mode, &unsignedp, 1);
1273 args[i].unsignedp = unsignedp;
1274 args[i].mode = mode;
1276 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1277 argpos < n_named_args);
1278 #ifdef FUNCTION_INCOMING_ARG
1279 /* If this is a sibling call and the machine has register windows, the
1280 register window has to be unwinded before calling the routine, so
1281 arguments have to go into the incoming registers. */
1282 args[i].tail_call_reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1283 argpos < n_named_args);
1285 args[i].tail_call_reg = args[i].reg;
1288 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1291 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1292 argpos < n_named_args);
1295 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1297 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1298 it means that we are to pass this arg in the register(s) designated
1299 by the PARALLEL, but also to pass it in the stack. */
1300 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1301 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1302 args[i].pass_on_stack = 1;
1304 /* If this is an addressable type, we must preallocate the stack
1305 since we must evaluate the object into its final location.
1307 If this is to be passed in both registers and the stack, it is simpler
1309 if (TREE_ADDRESSABLE (type)
1310 || (args[i].pass_on_stack && args[i].reg != 0))
1311 *must_preallocate = 1;
1313 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1314 we cannot consider this function call constant. */
1315 if (TREE_ADDRESSABLE (type))
1316 *ecf_flags &= ~(ECF_CONST | ECF_PURE);
1318 /* Compute the stack-size of this argument. */
1319 if (args[i].reg == 0 || args[i].partial != 0
1320 || reg_parm_stack_space > 0
1321 || args[i].pass_on_stack)
1322 locate_and_pad_parm (mode, type,
1323 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1328 fndecl, args_size, &args[i].offset,
1329 &args[i].size, &alignment_pad);
1331 #ifndef ARGS_GROW_DOWNWARD
1332 args[i].slot_offset = *args_size;
1335 args[i].alignment_pad = alignment_pad;
1337 /* If a part of the arg was put into registers,
1338 don't include that part in the amount pushed. */
1339 if (reg_parm_stack_space == 0 && ! args[i].pass_on_stack)
1340 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1341 / (PARM_BOUNDARY / BITS_PER_UNIT)
1342 * (PARM_BOUNDARY / BITS_PER_UNIT));
1344 /* Update ARGS_SIZE, the total stack space for args so far. */
1346 args_size->constant += args[i].size.constant;
1347 if (args[i].size.var)
1349 ADD_PARM_SIZE (*args_size, args[i].size.var);
1352 /* Since the slot offset points to the bottom of the slot,
1353 we must record it after incrementing if the args grow down. */
1354 #ifdef ARGS_GROW_DOWNWARD
1355 args[i].slot_offset = *args_size;
1357 args[i].slot_offset.constant = -args_size->constant;
1359 SUB_PARM_SIZE (args[i].slot_offset, args_size->var);
1362 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1363 have been used, etc. */
1365 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1366 argpos < n_named_args);
1370 /* Update ARGS_SIZE to contain the total size for the argument block.
1371 Return the original constant component of the argument block's size.
1373 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1374 for arguments passed in registers. */
1377 compute_argument_block_size (reg_parm_stack_space, args_size,
1378 preferred_stack_boundary)
1379 int reg_parm_stack_space;
1380 struct args_size *args_size;
1381 int preferred_stack_boundary ATTRIBUTE_UNUSED;
1383 int unadjusted_args_size = args_size->constant;
1385 /* For accumulate outgoing args mode we don't need to align, since the frame
1386 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1387 backends from generating misaligned frame sizes. */
1388 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1389 preferred_stack_boundary = STACK_BOUNDARY;
1391 /* Compute the actual size of the argument block required. The variable
1392 and constant sizes must be combined, the size may have to be rounded,
1393 and there may be a minimum required size. */
1397 args_size->var = ARGS_SIZE_TREE (*args_size);
1398 args_size->constant = 0;
1400 preferred_stack_boundary /= BITS_PER_UNIT;
1401 if (preferred_stack_boundary > 1)
1403 /* We don't handle this case yet. To handle it correctly we have
1404 to add the delta, round and subtract the delta.
1405 Currently no machine description requires this support. */
1406 if (stack_pointer_delta & (preferred_stack_boundary - 1))
1408 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1411 if (reg_parm_stack_space > 0)
1414 = size_binop (MAX_EXPR, args_size->var,
1415 ssize_int (reg_parm_stack_space));
1417 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1418 /* The area corresponding to register parameters is not to count in
1419 the size of the block we need. So make the adjustment. */
1421 = size_binop (MINUS_EXPR, args_size->var,
1422 ssize_int (reg_parm_stack_space));
1428 preferred_stack_boundary /= BITS_PER_UNIT;
1429 if (preferred_stack_boundary < 1)
1430 preferred_stack_boundary = 1;
1431 args_size->constant = (((args_size->constant
1432 + stack_pointer_delta
1433 + preferred_stack_boundary - 1)
1434 / preferred_stack_boundary
1435 * preferred_stack_boundary)
1436 - stack_pointer_delta);
1438 args_size->constant = MAX (args_size->constant,
1439 reg_parm_stack_space);
1441 #ifdef MAYBE_REG_PARM_STACK_SPACE
1442 if (reg_parm_stack_space == 0)
1443 args_size->constant = 0;
1446 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1447 args_size->constant -= reg_parm_stack_space;
1450 return unadjusted_args_size;
1453 /* Precompute parameters as needed for a function call.
1455 FLAGS is mask of ECF_* constants.
1457 NUM_ACTUALS is the number of arguments.
1459 ARGS is an array containing information for each argument; this
1460 routine fills in the INITIAL_VALUE and VALUE fields for each
1461 precomputed argument. */
1464 precompute_arguments (flags, num_actuals, args)
1467 struct arg_data *args;
1471 /* If this function call is cse'able, precompute all the parameters.
1472 Note that if the parameter is constructed into a temporary, this will
1473 cause an additional copy because the parameter will be constructed
1474 into a temporary location and then copied into the outgoing arguments.
1475 If a parameter contains a call to alloca and this function uses the
1476 stack, precompute the parameter. */
1478 /* If we preallocated the stack space, and some arguments must be passed
1479 on the stack, then we must precompute any parameter which contains a
1480 function call which will store arguments on the stack.
1481 Otherwise, evaluating the parameter may clobber previous parameters
1482 which have already been stored into the stack. (we have code to avoid
1483 such case by saving the outgoing stack arguments, but it results in
1486 for (i = 0; i < num_actuals; i++)
1487 if ((flags & (ECF_CONST | ECF_PURE))
1488 || calls_function (args[i].tree_value, !ACCUMULATE_OUTGOING_ARGS))
1490 enum machine_mode mode;
1492 /* If this is an addressable type, we cannot pre-evaluate it. */
1493 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1499 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1501 preserve_temp_slots (args[i].value);
1504 /* ANSI doesn't require a sequence point here,
1505 but PCC has one, so this will avoid some problems. */
1508 args[i].initial_value = args[i].value
1509 = protect_from_queue (args[i].value, 0);
1511 mode = TYPE_MODE (TREE_TYPE (args[i].tree_value));
1512 if (mode != args[i].mode)
1515 = convert_modes (args[i].mode, mode,
1516 args[i].value, args[i].unsignedp);
1517 #ifdef PROMOTE_FOR_CALL_ONLY
1518 /* CSE will replace this only if it contains args[i].value
1519 pseudo, so convert it down to the declared mode using
1521 if (GET_CODE (args[i].value) == REG
1522 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1524 args[i].initial_value
1525 = gen_lowpart_SUBREG (mode, args[i].value);
1526 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1527 SUBREG_PROMOTED_UNSIGNED_P (args[i].initial_value)
1528 = args[i].unsignedp;
1535 /* Given the current state of MUST_PREALLOCATE and information about
1536 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1537 compute and return the final value for MUST_PREALLOCATE. */
1540 finalize_must_preallocate (must_preallocate, num_actuals, args, args_size)
1541 int must_preallocate;
1543 struct arg_data *args;
1544 struct args_size *args_size;
1546 /* See if we have or want to preallocate stack space.
1548 If we would have to push a partially-in-regs parm
1549 before other stack parms, preallocate stack space instead.
1551 If the size of some parm is not a multiple of the required stack
1552 alignment, we must preallocate.
1554 If the total size of arguments that would otherwise create a copy in
1555 a temporary (such as a CALL) is more than half the total argument list
1556 size, preallocation is faster.
1558 Another reason to preallocate is if we have a machine (like the m88k)
1559 where stack alignment is required to be maintained between every
1560 pair of insns, not just when the call is made. However, we assume here
1561 that such machines either do not have push insns (and hence preallocation
1562 would occur anyway) or the problem is taken care of with
1565 if (! must_preallocate)
1567 int partial_seen = 0;
1568 int copy_to_evaluate_size = 0;
1571 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1573 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1575 else if (partial_seen && args[i].reg == 0)
1576 must_preallocate = 1;
1578 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1579 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1580 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1581 || TREE_CODE (args[i].tree_value) == COND_EXPR
1582 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1583 copy_to_evaluate_size
1584 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1587 if (copy_to_evaluate_size * 2 >= args_size->constant
1588 && args_size->constant > 0)
1589 must_preallocate = 1;
1591 return must_preallocate;
1594 /* If we preallocated stack space, compute the address of each argument
1595 and store it into the ARGS array.
1597 We need not ensure it is a valid memory address here; it will be
1598 validized when it is used.
1600 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1603 compute_argument_addresses (args, argblock, num_actuals)
1604 struct arg_data *args;
1610 rtx arg_reg = argblock;
1611 int i, arg_offset = 0;
1613 if (GET_CODE (argblock) == PLUS)
1614 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1616 for (i = 0; i < num_actuals; i++)
1618 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1619 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1622 /* Skip this parm if it will not be passed on the stack. */
1623 if (! args[i].pass_on_stack && args[i].reg != 0)
1626 if (GET_CODE (offset) == CONST_INT)
1627 addr = plus_constant (arg_reg, INTVAL (offset));
1629 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1631 addr = plus_constant (addr, arg_offset);
1632 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1633 set_mem_attributes (args[i].stack,
1634 TREE_TYPE (args[i].tree_value), 1);
1636 if (GET_CODE (slot_offset) == CONST_INT)
1637 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1639 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1641 addr = plus_constant (addr, arg_offset);
1642 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1643 set_mem_attributes (args[i].stack_slot,
1644 TREE_TYPE (args[i].tree_value), 1);
1646 /* Function incoming arguments may overlap with sibling call
1647 outgoing arguments and we cannot allow reordering of reads
1648 from function arguments with stores to outgoing arguments
1649 of sibling calls. */
1650 set_mem_alias_set (args[i].stack, 0);
1651 set_mem_alias_set (args[i].stack_slot, 0);
1656 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1657 in a call instruction.
1659 FNDECL is the tree node for the target function. For an indirect call
1660 FNDECL will be NULL_TREE.
1662 EXP is the CALL_EXPR for this call. */
1665 rtx_for_function_call (fndecl, exp)
1671 /* Get the function to call, in the form of RTL. */
1674 /* If this is the first use of the function, see if we need to
1675 make an external definition for it. */
1676 if (! TREE_USED (fndecl))
1678 assemble_external (fndecl);
1679 TREE_USED (fndecl) = 1;
1682 /* Get a SYMBOL_REF rtx for the function address. */
1683 funexp = XEXP (DECL_RTL (fndecl), 0);
1686 /* Generate an rtx (probably a pseudo-register) for the address. */
1691 = expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1692 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1698 /* Do the register loads required for any wholly-register parms or any
1699 parms which are passed both on the stack and in a register. Their
1700 expressions were already evaluated.
1702 Mark all register-parms as living through the call, putting these USE
1703 insns in the CALL_INSN_FUNCTION_USAGE field. */
1706 load_register_parameters (args, num_actuals, call_fusage, flags)
1707 struct arg_data *args;
1714 #ifdef LOAD_ARGS_REVERSED
1715 for (i = num_actuals - 1; i >= 0; i--)
1717 for (i = 0; i < num_actuals; i++)
1720 rtx reg = ((flags & ECF_SIBCALL)
1721 ? args[i].tail_call_reg : args[i].reg);
1722 int partial = args[i].partial;
1727 /* Set to non-negative if must move a word at a time, even if just
1728 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1729 we just use a normal move insn. This value can be zero if the
1730 argument is a zero size structure with no fields. */
1731 nregs = (partial ? partial
1732 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1733 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1734 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1737 /* Handle calls that pass values in multiple non-contiguous
1738 locations. The Irix 6 ABI has examples of this. */
1740 if (GET_CODE (reg) == PARALLEL)
1741 emit_group_load (reg, args[i].value,
1742 int_size_in_bytes (TREE_TYPE (args[i].tree_value)));
1744 /* If simple case, just do move. If normal partial, store_one_arg
1745 has already loaded the register for us. In all other cases,
1746 load the register(s) from memory. */
1748 else if (nregs == -1)
1749 emit_move_insn (reg, args[i].value);
1751 /* If we have pre-computed the values to put in the registers in
1752 the case of non-aligned structures, copy them in now. */
1754 else if (args[i].n_aligned_regs != 0)
1755 for (j = 0; j < args[i].n_aligned_regs; j++)
1756 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1757 args[i].aligned_regs[j]);
1759 else if (partial == 0 || args[i].pass_on_stack)
1760 move_block_to_reg (REGNO (reg),
1761 validize_mem (args[i].value), nregs,
1764 /* Handle calls that pass values in multiple non-contiguous
1765 locations. The Irix 6 ABI has examples of this. */
1766 if (GET_CODE (reg) == PARALLEL)
1767 use_group_regs (call_fusage, reg);
1768 else if (nregs == -1)
1769 use_reg (call_fusage, reg);
1771 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1776 /* Try to integrate function. See expand_inline_function for documentation
1777 about the parameters. */
1780 try_to_integrate (fndecl, actparms, target, ignore, type, structure_value_addr)
1786 rtx structure_value_addr;
1791 rtx old_stack_level = 0;
1792 int reg_parm_stack_space = 0;
1794 #ifdef REG_PARM_STACK_SPACE
1795 #ifdef MAYBE_REG_PARM_STACK_SPACE
1796 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1798 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1802 before_call = get_last_insn ();
1804 timevar_push (TV_INTEGRATION);
1806 temp = expand_inline_function (fndecl, actparms, target,
1808 structure_value_addr);
1810 timevar_pop (TV_INTEGRATION);
1812 /* If inlining succeeded, return. */
1813 if (temp != (rtx) (HOST_WIDE_INT) - 1)
1815 if (ACCUMULATE_OUTGOING_ARGS)
1817 /* If the outgoing argument list must be preserved, push
1818 the stack before executing the inlined function if it
1821 for (i = reg_parm_stack_space - 1; i >= 0; i--)
1822 if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
1825 if (stack_arg_under_construction || i >= 0)
1828 = before_call ? NEXT_INSN (before_call) : get_insns ();
1829 rtx insn = NULL_RTX, seq;
1831 /* Look for a call in the inline function code.
1832 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1833 nonzero then there is a call and it is not necessary
1834 to scan the insns. */
1836 if (DECL_SAVED_INSNS (fndecl)->outgoing_args_size == 0)
1837 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1838 if (GET_CODE (insn) == CALL_INSN)
1843 /* Reserve enough stack space so that the largest
1844 argument list of any function call in the inline
1845 function does not overlap the argument list being
1846 evaluated. This is usually an overestimate because
1847 allocate_dynamic_stack_space reserves space for an
1848 outgoing argument list in addition to the requested
1849 space, but there is no way to ask for stack space such
1850 that an argument list of a certain length can be
1853 Add the stack space reserved for register arguments, if
1854 any, in the inline function. What is really needed is the
1855 largest value of reg_parm_stack_space in the inline
1856 function, but that is not available. Using the current
1857 value of reg_parm_stack_space is wrong, but gives
1858 correct results on all supported machines. */
1860 int adjust = (DECL_SAVED_INSNS (fndecl)->outgoing_args_size
1861 + reg_parm_stack_space);
1864 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1865 allocate_dynamic_stack_space (GEN_INT (adjust),
1866 NULL_RTX, BITS_PER_UNIT);
1869 emit_insns_before (seq, first_insn);
1870 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1875 /* If the result is equivalent to TARGET, return TARGET to simplify
1876 checks in store_expr. They can be equivalent but not equal in the
1877 case of a function that returns BLKmode. */
1878 if (temp != target && rtx_equal_p (temp, target))
1883 /* If inlining failed, mark FNDECL as needing to be compiled
1884 separately after all. If function was declared inline,
1886 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1887 && optimize > 0 && !TREE_ADDRESSABLE (fndecl))
1889 warning_with_decl (fndecl, "inlining failed in call to `%s'");
1890 warning ("called from here");
1892 mark_addressable (fndecl);
1893 return (rtx) (HOST_WIDE_INT) - 1;
1896 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1897 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1898 bytes, then we would need to push some additional bytes to pad the
1899 arguments. So, we compute an adjust to the stack pointer for an
1900 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1901 bytes. Then, when the arguments are pushed the stack will be perfectly
1902 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1903 be popped after the call. Returns the adjustment. */
1906 combine_pending_stack_adjustment_and_call (unadjusted_args_size,
1908 preferred_unit_stack_boundary)
1909 int unadjusted_args_size;
1910 struct args_size *args_size;
1911 int preferred_unit_stack_boundary;
1913 /* The number of bytes to pop so that the stack will be
1914 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1915 HOST_WIDE_INT adjustment;
1916 /* The alignment of the stack after the arguments are pushed, if we
1917 just pushed the arguments without adjust the stack here. */
1918 HOST_WIDE_INT unadjusted_alignment;
1920 unadjusted_alignment
1921 = ((stack_pointer_delta + unadjusted_args_size)
1922 % preferred_unit_stack_boundary);
1924 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1925 as possible -- leaving just enough left to cancel out the
1926 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1927 PENDING_STACK_ADJUST is non-negative, and congruent to
1928 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1930 /* Begin by trying to pop all the bytes. */
1931 unadjusted_alignment
1932 = (unadjusted_alignment
1933 - (pending_stack_adjust % preferred_unit_stack_boundary));
1934 adjustment = pending_stack_adjust;
1935 /* Push enough additional bytes that the stack will be aligned
1936 after the arguments are pushed. */
1937 if (preferred_unit_stack_boundary > 1)
1939 if (unadjusted_alignment > 0)
1940 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1942 adjustment += unadjusted_alignment;
1945 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1946 bytes after the call. The right number is the entire
1947 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1948 by the arguments in the first place. */
1950 = pending_stack_adjust - adjustment + unadjusted_args_size;
1955 /* Scan X expression if it does not dereference any argument slots
1956 we already clobbered by tail call arguments (as noted in stored_args_map
1958 Return non-zero if X expression dereferences such argument slots,
1962 check_sibcall_argument_overlap_1 (x)
1973 code = GET_CODE (x);
1977 if (XEXP (x, 0) == current_function_internal_arg_pointer)
1979 else if (GET_CODE (XEXP (x, 0)) == PLUS
1980 && XEXP (XEXP (x, 0), 0) ==
1981 current_function_internal_arg_pointer
1982 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
1983 i = INTVAL (XEXP (XEXP (x, 0), 1));
1987 #ifdef ARGS_GROW_DOWNWARD
1988 i = -i - GET_MODE_SIZE (GET_MODE (x));
1991 for (k = 0; k < GET_MODE_SIZE (GET_MODE (x)); k++)
1992 if (i + k < stored_args_map->n_bits
1993 && TEST_BIT (stored_args_map, i + k))
1999 /* Scan all subexpressions. */
2000 fmt = GET_RTX_FORMAT (code);
2001 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2005 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2008 else if (*fmt == 'E')
2010 for (j = 0; j < XVECLEN (x, i); j++)
2011 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2018 /* Scan sequence after INSN if it does not dereference any argument slots
2019 we already clobbered by tail call arguments (as noted in stored_args_map
2020 bitmap). Add stack slots for ARG to stored_args_map bitmap afterwards.
2021 Return non-zero if sequence after INSN dereferences such argument slots,
2025 check_sibcall_argument_overlap (insn, arg)
2027 struct arg_data *arg;
2031 if (insn == NULL_RTX)
2032 insn = get_insns ();
2034 insn = NEXT_INSN (insn);
2036 for (; insn; insn = NEXT_INSN (insn))
2038 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2041 #ifdef ARGS_GROW_DOWNWARD
2042 low = -arg->slot_offset.constant - arg->size.constant;
2044 low = arg->slot_offset.constant;
2047 for (high = low + arg->size.constant; low < high; low++)
2048 SET_BIT (stored_args_map, low);
2049 return insn != NULL_RTX;
2052 /* Generate all the code for a function call
2053 and return an rtx for its value.
2054 Store the value in TARGET (specified as an rtx) if convenient.
2055 If the value is stored in TARGET then TARGET is returned.
2056 If IGNORE is nonzero, then we ignore the value of the function call. */
2059 expand_call (exp, target, ignore)
2064 /* Nonzero if we are currently expanding a call. */
2065 static int currently_expanding_call = 0;
2067 /* List of actual parameters. */
2068 tree actparms = TREE_OPERAND (exp, 1);
2069 /* RTX for the function to be called. */
2071 /* Sequence of insns to perform a tail recursive "call". */
2072 rtx tail_recursion_insns = NULL_RTX;
2073 /* Sequence of insns to perform a normal "call". */
2074 rtx normal_call_insns = NULL_RTX;
2075 /* Sequence of insns to perform a tail recursive "call". */
2076 rtx tail_call_insns = NULL_RTX;
2077 /* Data type of the function. */
2079 /* Declaration of the function being called,
2080 or 0 if the function is computed (not known by name). */
2083 int try_tail_call = 1;
2084 int try_tail_recursion = 1;
2087 /* Register in which non-BLKmode value will be returned,
2088 or 0 if no value or if value is BLKmode. */
2090 /* Address where we should return a BLKmode value;
2091 0 if value not BLKmode. */
2092 rtx structure_value_addr = 0;
2093 /* Nonzero if that address is being passed by treating it as
2094 an extra, implicit first parameter. Otherwise,
2095 it is passed by being copied directly into struct_value_rtx. */
2096 int structure_value_addr_parm = 0;
2097 /* Size of aggregate value wanted, or zero if none wanted
2098 or if we are using the non-reentrant PCC calling convention
2099 or expecting the value in registers. */
2100 HOST_WIDE_INT struct_value_size = 0;
2101 /* Nonzero if called function returns an aggregate in memory PCC style,
2102 by returning the address of where to find it. */
2103 int pcc_struct_value = 0;
2105 /* Number of actual parameters in this call, including struct value addr. */
2107 /* Number of named args. Args after this are anonymous ones
2108 and they must all go on the stack. */
2111 /* Vector of information about each argument.
2112 Arguments are numbered in the order they will be pushed,
2113 not the order they are written. */
2114 struct arg_data *args;
2116 /* Total size in bytes of all the stack-parms scanned so far. */
2117 struct args_size args_size;
2118 struct args_size adjusted_args_size;
2119 /* Size of arguments before any adjustments (such as rounding). */
2120 int unadjusted_args_size;
2121 /* Data on reg parms scanned so far. */
2122 CUMULATIVE_ARGS args_so_far;
2123 /* Nonzero if a reg parm has been scanned. */
2125 /* Nonzero if this is an indirect function call. */
2127 /* Nonzero if we must avoid push-insns in the args for this call.
2128 If stack space is allocated for register parameters, but not by the
2129 caller, then it is preallocated in the fixed part of the stack frame.
2130 So the entire argument block must then be preallocated (i.e., we
2131 ignore PUSH_ROUNDING in that case). */
2133 int must_preallocate = !PUSH_ARGS;
2135 /* Size of the stack reserved for parameter registers. */
2136 int reg_parm_stack_space = 0;
2138 /* Address of space preallocated for stack parms
2139 (on machines that lack push insns), or 0 if space not preallocated. */
2142 /* Mask of ECF_ flags. */
2144 /* Nonzero if this is a call to an inline function. */
2145 int is_integrable = 0;
2146 #ifdef REG_PARM_STACK_SPACE
2147 /* Define the boundary of the register parm stack space that needs to be
2149 int low_to_save = -1, high_to_save;
2150 rtx save_area = 0; /* Place that it is saved */
2153 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2154 char *initial_stack_usage_map = stack_usage_map;
2155 int old_stack_arg_under_construction = 0;
2157 rtx old_stack_level = 0;
2158 int old_pending_adj = 0;
2159 int old_inhibit_defer_pop = inhibit_defer_pop;
2160 int old_stack_allocated;
2162 tree p = TREE_OPERAND (exp, 0);
2164 /* The alignment of the stack, in bits. */
2165 HOST_WIDE_INT preferred_stack_boundary;
2166 /* The alignment of the stack, in bytes. */
2167 HOST_WIDE_INT preferred_unit_stack_boundary;
2169 /* See if this is "nothrow" function call. */
2170 if (TREE_NOTHROW (exp))
2171 flags |= ECF_NOTHROW;
2173 /* See if we can find a DECL-node for the actual function.
2174 As a result, decide whether this is a call to an integrable function. */
2176 fndecl = get_callee_fndecl (exp);
2180 && fndecl != current_function_decl
2181 && DECL_INLINE (fndecl)
2182 && DECL_SAVED_INSNS (fndecl)
2183 && DECL_SAVED_INSNS (fndecl)->inlinable)
2185 else if (! TREE_ADDRESSABLE (fndecl))
2187 /* In case this function later becomes inlinable,
2188 record that there was already a non-inline call to it.
2190 Use abstraction instead of setting TREE_ADDRESSABLE
2192 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2195 warning_with_decl (fndecl, "can't inline call to `%s'");
2196 warning ("called from here");
2198 mark_addressable (fndecl);
2201 flags |= flags_from_decl_or_type (fndecl);
2204 /* If we don't have specific function to call, see if we have a
2205 attributes set in the type. */
2207 flags |= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p)));
2209 /* Mark if the function returns with the stack pointer depressed. */
2210 if (TREE_CODE (TREE_TYPE (TREE_TYPE (p))) == FUNCTION_TYPE
2211 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (TREE_TYPE (p))))
2213 flags |= ECF_SP_DEPRESSED;
2214 flags &= ~(ECF_PURE | ECF_CONST);
2217 #ifdef REG_PARM_STACK_SPACE
2218 #ifdef MAYBE_REG_PARM_STACK_SPACE
2219 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
2221 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2225 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2226 if (reg_parm_stack_space > 0 && PUSH_ARGS)
2227 must_preallocate = 1;
2230 /* Warn if this value is an aggregate type,
2231 regardless of which calling convention we are using for it. */
2232 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2233 warning ("function call has aggregate value");
2235 /* Set up a place to return a structure. */
2237 /* Cater to broken compilers. */
2238 if (aggregate_value_p (exp))
2240 /* This call returns a big structure. */
2241 flags &= ~(ECF_CONST | ECF_PURE);
2243 #ifdef PCC_STATIC_STRUCT_RETURN
2245 pcc_struct_value = 1;
2246 /* Easier than making that case work right. */
2249 /* In case this is a static function, note that it has been
2251 if (! TREE_ADDRESSABLE (fndecl))
2252 mark_addressable (fndecl);
2256 #else /* not PCC_STATIC_STRUCT_RETURN */
2258 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2260 if (target && GET_CODE (target) == MEM)
2261 structure_value_addr = XEXP (target, 0);
2264 /* For variable-sized objects, we must be called with a target
2265 specified. If we were to allocate space on the stack here,
2266 we would have no way of knowing when to free it. */
2267 rtx d = assign_temp (TREE_TYPE (exp), 1, 1, 1);
2269 mark_temp_addr_taken (d);
2270 structure_value_addr = XEXP (d, 0);
2274 #endif /* not PCC_STATIC_STRUCT_RETURN */
2277 /* If called function is inline, try to integrate it. */
2281 rtx temp = try_to_integrate (fndecl, actparms, target,
2282 ignore, TREE_TYPE (exp),
2283 structure_value_addr);
2284 if (temp != (rtx) (HOST_WIDE_INT) - 1)
2288 /* Figure out the amount to which the stack should be aligned. */
2289 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2291 /* Operand 0 is a pointer-to-function; get the type of the function. */
2292 funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
2293 if (! POINTER_TYPE_P (funtype))
2295 funtype = TREE_TYPE (funtype);
2297 /* See if this is a call to a function that can return more than once
2298 or a call to longjmp or malloc. */
2299 flags |= special_function_p (fndecl, flags);
2301 if (flags & ECF_MAY_BE_ALLOCA)
2302 current_function_calls_alloca = 1;
2304 /* If struct_value_rtx is 0, it means pass the address
2305 as if it were an extra parameter. */
2306 if (structure_value_addr && struct_value_rtx == 0)
2308 /* If structure_value_addr is a REG other than
2309 virtual_outgoing_args_rtx, we can use always use it. If it
2310 is not a REG, we must always copy it into a register.
2311 If it is virtual_outgoing_args_rtx, we must copy it to another
2312 register in some cases. */
2313 rtx temp = (GET_CODE (structure_value_addr) != REG
2314 || (ACCUMULATE_OUTGOING_ARGS
2315 && stack_arg_under_construction
2316 && structure_value_addr == virtual_outgoing_args_rtx)
2317 ? copy_addr_to_reg (structure_value_addr)
2318 : structure_value_addr);
2321 = tree_cons (error_mark_node,
2322 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2325 structure_value_addr_parm = 1;
2328 /* Count the arguments and set NUM_ACTUALS. */
2329 for (p = actparms, num_actuals = 0; p; p = TREE_CHAIN (p))
2332 /* Compute number of named args.
2333 Normally, don't include the last named arg if anonymous args follow.
2334 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2335 (If no anonymous args follow, the result of list_length is actually
2336 one too large. This is harmless.)
2338 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2339 zero, this machine will be able to place unnamed args that were
2340 passed in registers into the stack. So treat all args as named.
2341 This allows the insns emitting for a specific argument list to be
2342 independent of the function declaration.
2344 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2345 reliable way to pass unnamed args in registers, so we must force
2346 them into memory. */
2348 if ((STRICT_ARGUMENT_NAMING
2349 || ! PRETEND_OUTGOING_VARARGS_NAMED)
2350 && TYPE_ARG_TYPES (funtype) != 0)
2352 = (list_length (TYPE_ARG_TYPES (funtype))
2353 /* Don't include the last named arg. */
2354 - (STRICT_ARGUMENT_NAMING ? 0 : 1)
2355 /* Count the struct value address, if it is passed as a parm. */
2356 + structure_value_addr_parm);
2358 /* If we know nothing, treat all args as named. */
2359 n_named_args = num_actuals;
2361 /* Start updating where the next arg would go.
2363 On some machines (such as the PA) indirect calls have a different
2364 calling convention than normal calls. The last argument in
2365 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2367 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, (fndecl == 0));
2369 /* Make a vector to hold all the information about each arg. */
2370 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
2371 memset ((char *) args, 0, num_actuals * sizeof (struct arg_data));
2373 /* Build up entries in the ARGS array, compute the size of the
2374 arguments into ARGS_SIZE, etc. */
2375 initialize_argument_information (num_actuals, args, &args_size,
2376 n_named_args, actparms, fndecl,
2377 &args_so_far, reg_parm_stack_space,
2378 &old_stack_level, &old_pending_adj,
2379 &must_preallocate, &flags);
2383 /* If this function requires a variable-sized argument list, don't
2384 try to make a cse'able block for this call. We may be able to
2385 do this eventually, but it is too complicated to keep track of
2386 what insns go in the cse'able block and which don't. */
2388 flags &= ~(ECF_CONST | ECF_PURE);
2389 must_preallocate = 1;
2392 /* Now make final decision about preallocating stack space. */
2393 must_preallocate = finalize_must_preallocate (must_preallocate,
2397 /* If the structure value address will reference the stack pointer, we
2398 must stabilize it. We don't need to do this if we know that we are
2399 not going to adjust the stack pointer in processing this call. */
2401 if (structure_value_addr
2402 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2403 || reg_mentioned_p (virtual_outgoing_args_rtx,
2404 structure_value_addr))
2406 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2407 structure_value_addr = copy_to_reg (structure_value_addr);
2409 /* Tail calls can make things harder to debug, and we're traditionally
2410 pushed these optimizations into -O2. Don't try if we're already
2411 expanding a call, as that means we're an argument. Don't try if
2412 there's cleanups, as we know there's code to follow the call.
2414 If rtx_equal_function_value_matters is false, that means we've
2415 finished with regular parsing. Which means that some of the
2416 machinery we use to generate tail-calls is no longer in place.
2417 This is most often true of sjlj-exceptions, which we couldn't
2418 tail-call to anyway. */
2420 if (currently_expanding_call++ != 0
2421 || !flag_optimize_sibling_calls
2422 || !rtx_equal_function_value_matters
2423 || any_pending_cleanups (1)
2425 try_tail_call = try_tail_recursion = 0;
2427 /* Tail recursion fails, when we are not dealing with recursive calls. */
2428 if (!try_tail_recursion
2429 || TREE_CODE (TREE_OPERAND (exp, 0)) != ADDR_EXPR
2430 || TREE_OPERAND (TREE_OPERAND (exp, 0), 0) != current_function_decl)
2431 try_tail_recursion = 0;
2433 /* Rest of purposes for tail call optimizations to fail. */
2435 #ifdef HAVE_sibcall_epilogue
2436 !HAVE_sibcall_epilogue
2441 /* Doing sibling call optimization needs some work, since
2442 structure_value_addr can be allocated on the stack.
2443 It does not seem worth the effort since few optimizable
2444 sibling calls will return a structure. */
2445 || structure_value_addr != NULL_RTX
2446 /* If the register holding the address is a callee saved
2447 register, then we lose. We have no way to prevent that,
2448 so we only allow calls to named functions. */
2449 /* ??? This could be done by having the insn constraints
2450 use a register class that is all call-clobbered. Any
2451 reload insns generated to fix things up would appear
2452 before the sibcall_epilogue. */
2453 || fndecl == NULL_TREE
2454 || (flags & (ECF_RETURNS_TWICE | ECF_LONGJMP))
2455 || TREE_THIS_VOLATILE (fndecl)
2456 || !FUNCTION_OK_FOR_SIBCALL (fndecl)
2457 /* If this function requires more stack slots than the current
2458 function, we cannot change it into a sibling call. */
2459 || args_size.constant > current_function_args_size
2460 /* If the callee pops its own arguments, then it must pop exactly
2461 the same number of arguments as the current function. */
2462 || RETURN_POPS_ARGS (fndecl, funtype, args_size.constant)
2463 != RETURN_POPS_ARGS (current_function_decl,
2464 TREE_TYPE (current_function_decl),
2465 current_function_args_size))
2468 if (try_tail_call || try_tail_recursion)
2471 actparms = NULL_TREE;
2472 /* Ok, we're going to give the tail call the old college try.
2473 This means we're going to evaluate the function arguments
2474 up to three times. There are two degrees of badness we can
2475 encounter, those that can be unsaved and those that can't.
2476 (See unsafe_for_reeval commentary for details.)
2478 Generate a new argument list. Pass safe arguments through
2479 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2480 For hard badness, evaluate them now and put their resulting
2481 rtx in a temporary VAR_DECL.
2483 initialize_argument_information has ordered the array for the
2484 order to be pushed, and we must remember this when reconstructing
2485 the original argument order. */
2487 if (PUSH_ARGS_REVERSED)
2496 i = num_actuals - 1;
2500 for (; i != end; i += inc)
2502 switch (unsafe_for_reeval (args[i].tree_value))
2507 case 1: /* Mildly unsafe. */
2508 args[i].tree_value = unsave_expr (args[i].tree_value);
2511 case 2: /* Wildly unsafe. */
2513 tree var = build_decl (VAR_DECL, NULL_TREE,
2514 TREE_TYPE (args[i].tree_value));
2516 expand_expr (args[i].tree_value, NULL_RTX,
2517 VOIDmode, EXPAND_NORMAL));
2518 args[i].tree_value = var;
2525 /* We need to build actparms for optimize_tail_recursion. We can
2526 safely trash away TREE_PURPOSE, since it is unused by this
2528 if (try_tail_recursion)
2529 actparms = tree_cons (NULL_TREE, args[i].tree_value, actparms);
2531 /* Expanding one of those dangerous arguments could have added
2532 cleanups, but otherwise give it a whirl. */
2533 if (any_pending_cleanups (1))
2534 try_tail_call = try_tail_recursion = 0;
2537 /* Generate a tail recursion sequence when calling ourselves. */
2539 if (try_tail_recursion)
2541 /* We want to emit any pending stack adjustments before the tail
2542 recursion "call". That way we know any adjustment after the tail
2543 recursion call can be ignored if we indeed use the tail recursion
2545 int save_pending_stack_adjust = pending_stack_adjust;
2546 int save_stack_pointer_delta = stack_pointer_delta;
2548 /* Emit any queued insns now; otherwise they would end up in
2549 only one of the alternates. */
2552 /* Use a new sequence to hold any RTL we generate. We do not even
2553 know if we will use this RTL yet. The final decision can not be
2554 made until after RTL generation for the entire function is
2557 /* If expanding any of the arguments creates cleanups, we can't
2558 do a tailcall. So, we'll need to pop the pending cleanups
2559 list. If, however, all goes well, and there are no cleanups
2560 then the call to expand_start_target_temps will have no
2562 expand_start_target_temps ();
2563 if (optimize_tail_recursion (actparms, get_last_insn ()))
2565 if (any_pending_cleanups (1))
2566 try_tail_call = try_tail_recursion = 0;
2568 tail_recursion_insns = get_insns ();
2570 expand_end_target_temps ();
2573 /* Restore the original pending stack adjustment for the sibling and
2574 normal call cases below. */
2575 pending_stack_adjust = save_pending_stack_adjust;
2576 stack_pointer_delta = save_stack_pointer_delta;
2579 if (profile_arc_flag && (flags & ECF_FORK_OR_EXEC))
2581 /* A fork duplicates the profile information, and an exec discards
2582 it. We can't rely on fork/exec to be paired. So write out the
2583 profile information we have gathered so far, and clear it. */
2584 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2585 is subject to race conditions, just as with multithreaded
2588 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__bb_fork_func"),
2593 /* Ensure current function's preferred stack boundary is at least
2594 what we need. We don't have to increase alignment for recursive
2596 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2597 && fndecl != current_function_decl)
2598 cfun->preferred_stack_boundary = preferred_stack_boundary;
2600 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2602 function_call_count++;
2604 /* We want to make two insn chains; one for a sibling call, the other
2605 for a normal call. We will select one of the two chains after
2606 initial RTL generation is complete. */
2607 for (pass = 0; pass < 2; pass++)
2609 int sibcall_failure = 0;
2610 /* We want to emit any pending stack adjustments before the tail
2611 recursion "call". That way we know any adjustment after the tail
2612 recursion call can be ignored if we indeed use the tail recursion
2614 int save_pending_stack_adjust = 0;
2615 int save_stack_pointer_delta = 0;
2617 rtx before_call, next_arg_reg;
2621 if (! try_tail_call)
2624 /* Emit any queued insns now; otherwise they would end up in
2625 only one of the alternates. */
2628 /* State variables we need to save and restore between
2630 save_pending_stack_adjust = pending_stack_adjust;
2631 save_stack_pointer_delta = stack_pointer_delta;
2634 flags &= ~ECF_SIBCALL;
2636 flags |= ECF_SIBCALL;
2638 /* Other state variables that we must reinitialize each time
2639 through the loop (that are not initialized by the loop itself). */
2643 /* Start a new sequence for the normal call case.
2645 From this point on, if the sibling call fails, we want to set
2646 sibcall_failure instead of continuing the loop. */
2651 /* We know at this point that there are not currently any
2652 pending cleanups. If, however, in the process of evaluating
2653 the arguments we were to create some, we'll need to be
2654 able to get rid of them. */
2655 expand_start_target_temps ();
2658 /* Don't let pending stack adjusts add up to too much.
2659 Also, do all pending adjustments now if there is any chance
2660 this might be a call to alloca or if we are expanding a sibling
2662 if (pending_stack_adjust >= 32
2663 || (pending_stack_adjust > 0 && (flags & ECF_MAY_BE_ALLOCA))
2665 do_pending_stack_adjust ();
2667 /* When calling a const function, we must pop the stack args right away,
2668 so that the pop is deleted or moved with the call. */
2669 if (flags & (ECF_CONST | ECF_PURE))
2672 /* Push the temporary stack slot level so that we can free any
2673 temporaries we make. */
2676 #ifdef FINAL_REG_PARM_STACK_SPACE
2677 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2680 /* Precompute any arguments as needed. */
2682 precompute_arguments (flags, num_actuals, args);
2684 /* Now we are about to start emitting insns that can be deleted
2685 if a libcall is deleted. */
2686 if (flags & (ECF_CONST | ECF_PURE | ECF_MALLOC))
2689 adjusted_args_size = args_size;
2690 /* Compute the actual size of the argument block required. The variable
2691 and constant sizes must be combined, the size may have to be rounded,
2692 and there may be a minimum required size. When generating a sibcall
2693 pattern, do not round up, since we'll be re-using whatever space our
2695 unadjusted_args_size
2696 = compute_argument_block_size (reg_parm_stack_space,
2697 &adjusted_args_size,
2699 : preferred_stack_boundary));
2701 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2703 /* The argument block when performing a sibling call is the
2704 incoming argument block. */
2707 argblock = virtual_incoming_args_rtx;
2708 stored_args_map = sbitmap_alloc (args_size.constant);
2709 sbitmap_zero (stored_args_map);
2712 /* If we have no actual push instructions, or shouldn't use them,
2713 make space for all args right now. */
2714 else if (adjusted_args_size.var != 0)
2716 if (old_stack_level == 0)
2718 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2719 old_pending_adj = pending_stack_adjust;
2720 pending_stack_adjust = 0;
2721 /* stack_arg_under_construction says whether a stack arg is
2722 being constructed at the old stack level. Pushing the stack
2723 gets a clean outgoing argument block. */
2724 old_stack_arg_under_construction = stack_arg_under_construction;
2725 stack_arg_under_construction = 0;
2727 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2731 /* Note that we must go through the motions of allocating an argument
2732 block even if the size is zero because we may be storing args
2733 in the area reserved for register arguments, which may be part of
2736 int needed = adjusted_args_size.constant;
2738 /* Store the maximum argument space used. It will be pushed by
2739 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2742 if (needed > current_function_outgoing_args_size)
2743 current_function_outgoing_args_size = needed;
2745 if (must_preallocate)
2747 if (ACCUMULATE_OUTGOING_ARGS)
2749 /* Since the stack pointer will never be pushed, it is
2750 possible for the evaluation of a parm to clobber
2751 something we have already written to the stack.
2752 Since most function calls on RISC machines do not use
2753 the stack, this is uncommon, but must work correctly.
2755 Therefore, we save any area of the stack that was already
2756 written and that we are using. Here we set up to do this
2757 by making a new stack usage map from the old one. The
2758 actual save will be done by store_one_arg.
2760 Another approach might be to try to reorder the argument
2761 evaluations to avoid this conflicting stack usage. */
2763 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2764 /* Since we will be writing into the entire argument area,
2765 the map must be allocated for its entire size, not just
2766 the part that is the responsibility of the caller. */
2767 needed += reg_parm_stack_space;
2770 #ifdef ARGS_GROW_DOWNWARD
2771 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2774 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2778 = (char *) alloca (highest_outgoing_arg_in_use);
2780 if (initial_highest_arg_in_use)
2781 memcpy (stack_usage_map, initial_stack_usage_map,
2782 initial_highest_arg_in_use);
2784 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2785 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2786 (highest_outgoing_arg_in_use
2787 - initial_highest_arg_in_use));
2790 /* The address of the outgoing argument list must not be
2791 copied to a register here, because argblock would be left
2792 pointing to the wrong place after the call to
2793 allocate_dynamic_stack_space below. */
2795 argblock = virtual_outgoing_args_rtx;
2799 if (inhibit_defer_pop == 0)
2801 /* Try to reuse some or all of the pending_stack_adjust
2802 to get this space. */
2804 = (combine_pending_stack_adjustment_and_call
2805 (unadjusted_args_size,
2806 &adjusted_args_size,
2807 preferred_unit_stack_boundary));
2809 /* combine_pending_stack_adjustment_and_call computes
2810 an adjustment before the arguments are allocated.
2811 Account for them and see whether or not the stack
2812 needs to go up or down. */
2813 needed = unadjusted_args_size - needed;
2817 /* We're releasing stack space. */
2818 /* ??? We can avoid any adjustment at all if we're
2819 already aligned. FIXME. */
2820 pending_stack_adjust = -needed;
2821 do_pending_stack_adjust ();
2825 /* We need to allocate space. We'll do that in
2826 push_block below. */
2827 pending_stack_adjust = 0;
2830 /* Special case this because overhead of `push_block' in
2831 this case is non-trivial. */
2833 argblock = virtual_outgoing_args_rtx;
2835 argblock = push_block (GEN_INT (needed), 0, 0);
2837 /* We only really need to call `copy_to_reg' in the case
2838 where push insns are going to be used to pass ARGBLOCK
2839 to a function call in ARGS. In that case, the stack
2840 pointer changes value from the allocation point to the
2841 call point, and hence the value of
2842 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2843 as well always do it. */
2844 argblock = copy_to_reg (argblock);
2846 /* The save/restore code in store_one_arg handles all
2847 cases except one: a constructor call (including a C
2848 function returning a BLKmode struct) to initialize
2850 if (stack_arg_under_construction)
2852 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2853 rtx push_size = GEN_INT (reg_parm_stack_space
2854 + adjusted_args_size.constant);
2856 rtx push_size = GEN_INT (adjusted_args_size.constant);
2858 if (old_stack_level == 0)
2860 emit_stack_save (SAVE_BLOCK, &old_stack_level,
2862 old_pending_adj = pending_stack_adjust;
2863 pending_stack_adjust = 0;
2864 /* stack_arg_under_construction says whether a stack
2865 arg is being constructed at the old stack level.
2866 Pushing the stack gets a clean outgoing argument
2868 old_stack_arg_under_construction
2869 = stack_arg_under_construction;
2870 stack_arg_under_construction = 0;
2871 /* Make a new map for the new argument list. */
2872 stack_usage_map = (char *)
2873 alloca (highest_outgoing_arg_in_use);
2874 memset (stack_usage_map, 0, highest_outgoing_arg_in_use);
2875 highest_outgoing_arg_in_use = 0;
2877 allocate_dynamic_stack_space (push_size, NULL_RTX,
2880 /* If argument evaluation might modify the stack pointer,
2881 copy the address of the argument list to a register. */
2882 for (i = 0; i < num_actuals; i++)
2883 if (args[i].pass_on_stack)
2885 argblock = copy_addr_to_reg (argblock);
2892 compute_argument_addresses (args, argblock, num_actuals);
2894 /* If we push args individually in reverse order, perform stack alignment
2895 before the first push (the last arg). */
2896 if (PUSH_ARGS_REVERSED && argblock == 0
2897 && adjusted_args_size.constant != unadjusted_args_size)
2899 /* When the stack adjustment is pending, we get better code
2900 by combining the adjustments. */
2901 if (pending_stack_adjust
2902 && ! (flags & (ECF_CONST | ECF_PURE))
2903 && ! inhibit_defer_pop)
2905 pending_stack_adjust
2906 = (combine_pending_stack_adjustment_and_call
2907 (unadjusted_args_size,
2908 &adjusted_args_size,
2909 preferred_unit_stack_boundary));
2910 do_pending_stack_adjust ();
2912 else if (argblock == 0)
2913 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2914 - unadjusted_args_size));
2916 /* Now that the stack is properly aligned, pops can't safely
2917 be deferred during the evaluation of the arguments. */
2920 funexp = rtx_for_function_call (fndecl, exp);
2922 /* Figure out the register where the value, if any, will come back. */
2924 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2925 && ! structure_value_addr)
2927 if (pcc_struct_value)
2928 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2929 fndecl, (pass == 0));
2931 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
2934 /* Precompute all register parameters. It isn't safe to compute anything
2935 once we have started filling any specific hard regs. */
2936 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2938 #ifdef REG_PARM_STACK_SPACE
2939 /* Save the fixed argument area if it's part of the caller's frame and
2940 is clobbered by argument setup for this call. */
2941 if (ACCUMULATE_OUTGOING_ARGS && pass)
2942 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2943 &low_to_save, &high_to_save);
2946 /* Now store (and compute if necessary) all non-register parms.
2947 These come before register parms, since they can require block-moves,
2948 which could clobber the registers used for register parms.
2949 Parms which have partial registers are not stored here,
2950 but we do preallocate space here if they want that. */
2952 for (i = 0; i < num_actuals; i++)
2953 if (args[i].reg == 0 || args[i].pass_on_stack)
2955 rtx before_arg = get_last_insn ();
2957 if (store_one_arg (&args[i], argblock, flags,
2958 adjusted_args_size.var != 0,
2959 reg_parm_stack_space)
2961 && check_sibcall_argument_overlap (before_arg,
2963 sibcall_failure = 1;
2966 /* If we have a parm that is passed in registers but not in memory
2967 and whose alignment does not permit a direct copy into registers,
2968 make a group of pseudos that correspond to each register that we
2970 if (STRICT_ALIGNMENT)
2971 store_unaligned_arguments_into_pseudos (args, num_actuals);
2973 /* Now store any partially-in-registers parm.
2974 This is the last place a block-move can happen. */
2976 for (i = 0; i < num_actuals; i++)
2977 if (args[i].partial != 0 && ! args[i].pass_on_stack)
2979 rtx before_arg = get_last_insn ();
2981 if (store_one_arg (&args[i], argblock, flags,
2982 adjusted_args_size.var != 0,
2983 reg_parm_stack_space)
2985 && check_sibcall_argument_overlap (before_arg,
2987 sibcall_failure = 1;
2990 /* If we pushed args in forward order, perform stack alignment
2991 after pushing the last arg. */
2992 if (!PUSH_ARGS_REVERSED && argblock == 0)
2993 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2994 - unadjusted_args_size));
2996 /* If register arguments require space on the stack and stack space
2997 was not preallocated, allocate stack space here for arguments
2998 passed in registers. */
2999 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3000 if (!ACCUMULATE_OUTGOING_ARGS
3001 && must_preallocate == 0 && reg_parm_stack_space > 0)
3002 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3005 /* Pass the function the address in which to return a
3007 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3009 emit_move_insn (struct_value_rtx,
3011 force_operand (structure_value_addr,
3014 if (GET_CODE (struct_value_rtx) == REG)
3015 use_reg (&call_fusage, struct_value_rtx);
3018 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
3019 reg_parm_seen, pass == 0);
3021 load_register_parameters (args, num_actuals, &call_fusage, flags);
3023 /* Perform postincrements before actually calling the function. */
3026 /* Save a pointer to the last insn before the call, so that we can
3027 later safely search backwards to find the CALL_INSN. */
3028 before_call = get_last_insn ();
3030 /* Set up next argument register. For sibling calls on machines
3031 with register windows this should be the incoming register. */
3032 #ifdef FUNCTION_INCOMING_ARG
3034 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
3038 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
3041 /* All arguments and registers used for the call must be set up by
3044 /* Stack must be properly aligned now. */
3045 if (pass && stack_pointer_delta % preferred_unit_stack_boundary)
3048 /* Generate the actual call instruction. */
3049 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
3050 adjusted_args_size.constant, struct_value_size,
3051 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3054 /* Verify that we've deallocated all the stack we used. */
3056 && old_stack_allocated != stack_pointer_delta - pending_stack_adjust)
3059 /* If call is cse'able, make appropriate pair of reg-notes around it.
3060 Test valreg so we don't crash; may safely ignore `const'
3061 if return type is void. Disable for PARALLEL return values, because
3062 we have no way to move such values into a pseudo register. */
3064 && (flags & (ECF_CONST | ECF_PURE))
3065 && valreg != 0 && GET_CODE (valreg) != PARALLEL)
3068 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3071 /* Mark the return value as a pointer if needed. */
3072 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3073 mark_reg_pointer (temp, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
3075 /* Construct an "equal form" for the value which mentions all the
3076 arguments in order as well as the function name. */
3077 for (i = 0; i < num_actuals; i++)
3078 note = gen_rtx_EXPR_LIST (VOIDmode, args[i].initial_value, note);
3079 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
3081 insns = get_insns ();
3084 if (flags & ECF_PURE)
3085 note = gen_rtx_EXPR_LIST (VOIDmode,
3086 gen_rtx_USE (VOIDmode,
3087 gen_rtx_MEM (BLKmode,
3088 gen_rtx_SCRATCH (VOIDmode))), note);
3090 emit_libcall_block (insns, temp, valreg, note);
3094 else if (flags & (ECF_CONST | ECF_PURE))
3096 /* Otherwise, just write out the sequence without a note. */
3097 rtx insns = get_insns ();
3102 else if (flags & ECF_MALLOC)
3104 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3107 /* The return value from a malloc-like function is a pointer. */
3108 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3109 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3111 emit_move_insn (temp, valreg);
3113 /* The return value from a malloc-like function can not alias
3115 last = get_last_insn ();
3117 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
3119 /* Write out the sequence. */
3120 insns = get_insns ();
3126 /* For calls to `setjmp', etc., inform flow.c it should complain
3127 if nonvolatile values are live. For functions that cannot return,
3128 inform flow that control does not fall through. */
3130 if ((flags & (ECF_NORETURN | ECF_LONGJMP)) || pass == 0)
3132 /* The barrier must be emitted
3133 immediately after the CALL_INSN. Some ports emit more
3134 than just a CALL_INSN above, so we must search for it here. */
3136 rtx last = get_last_insn ();
3137 while (GET_CODE (last) != CALL_INSN)
3139 last = PREV_INSN (last);
3140 /* There was no CALL_INSN? */
3141 if (last == before_call)
3145 emit_barrier_after (last);
3148 if (flags & ECF_LONGJMP)
3149 current_function_calls_longjmp = 1;
3151 /* If this function is returning into a memory location marked as
3152 readonly, it means it is initializing that location. But we normally
3153 treat functions as not clobbering such locations, so we need to
3154 specify that this one does. */
3155 if (target != 0 && GET_CODE (target) == MEM
3156 && structure_value_addr != 0 && RTX_UNCHANGING_P (target))
3157 emit_insn (gen_rtx_CLOBBER (VOIDmode, target));
3159 /* If value type not void, return an rtx for the value. */
3161 /* If there are cleanups to be called, don't use a hard reg as target.
3162 We need to double check this and see if it matters anymore. */
3163 if (any_pending_cleanups (1))
3165 if (target && REG_P (target)
3166 && REGNO (target) < FIRST_PSEUDO_REGISTER)
3168 sibcall_failure = 1;
3171 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
3174 target = const0_rtx;
3176 else if (structure_value_addr)
3178 if (target == 0 || GET_CODE (target) != MEM)
3181 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3182 memory_address (TYPE_MODE (TREE_TYPE (exp)),
3183 structure_value_addr));
3184 set_mem_attributes (target, exp, 1);
3187 else if (pcc_struct_value)
3189 /* This is the special C++ case where we need to
3190 know what the true target was. We take care to
3191 never use this value more than once in one expression. */
3192 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3193 copy_to_reg (valreg));
3194 set_mem_attributes (target, exp, 1);
3196 /* Handle calls that return values in multiple non-contiguous locations.
3197 The Irix 6 ABI has examples of this. */
3198 else if (GET_CODE (valreg) == PARALLEL)
3202 /* This will only be assigned once, so it can be readonly. */
3203 tree nt = build_qualified_type (TREE_TYPE (exp),
3204 (TYPE_QUALS (TREE_TYPE (exp))
3205 | TYPE_QUAL_CONST));
3207 target = assign_temp (nt, 0, 1, 1);
3208 preserve_temp_slots (target);
3211 if (! rtx_equal_p (target, valreg))
3212 emit_group_store (target, valreg,
3213 int_size_in_bytes (TREE_TYPE (exp)));
3215 /* We can not support sibling calls for this case. */
3216 sibcall_failure = 1;
3219 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
3220 && GET_MODE (target) == GET_MODE (valreg))
3222 /* TARGET and VALREG cannot be equal at this point because the
3223 latter would not have REG_FUNCTION_VALUE_P true, while the
3224 former would if it were referring to the same register.
3226 If they refer to the same register, this move will be a no-op,
3227 except when function inlining is being done. */
3228 emit_move_insn (target, valreg);
3230 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3232 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3234 /* We can not support sibling calls for this case. */
3235 sibcall_failure = 1;
3238 target = copy_to_reg (valreg);
3240 #ifdef PROMOTE_FUNCTION_RETURN
3241 /* If we promoted this return value, make the proper SUBREG. TARGET
3242 might be const0_rtx here, so be careful. */
3243 if (GET_CODE (target) == REG
3244 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3245 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3247 tree type = TREE_TYPE (exp);
3248 int unsignedp = TREE_UNSIGNED (type);
3251 /* If we don't promote as expected, something is wrong. */
3252 if (GET_MODE (target)
3253 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
3256 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3257 && GET_MODE_SIZE (GET_MODE (target))
3258 > GET_MODE_SIZE (TYPE_MODE (type)))
3260 offset = GET_MODE_SIZE (GET_MODE (target))
3261 - GET_MODE_SIZE (TYPE_MODE (type));
3262 if (! BYTES_BIG_ENDIAN)
3263 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3264 else if (! WORDS_BIG_ENDIAN)
3265 offset %= UNITS_PER_WORD;
3267 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3268 SUBREG_PROMOTED_VAR_P (target) = 1;
3269 SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
3273 /* If size of args is variable or this was a constructor call for a stack
3274 argument, restore saved stack-pointer value. */
3276 if (old_stack_level && ! (flags & ECF_SP_DEPRESSED))
3278 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3279 pending_stack_adjust = old_pending_adj;
3280 stack_arg_under_construction = old_stack_arg_under_construction;
3281 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3282 stack_usage_map = initial_stack_usage_map;
3283 sibcall_failure = 1;
3285 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3287 #ifdef REG_PARM_STACK_SPACE
3290 restore_fixed_argument_area (save_area, argblock,
3291 high_to_save, low_to_save);
3295 /* If we saved any argument areas, restore them. */
3296 for (i = 0; i < num_actuals; i++)
3297 if (args[i].save_area)
3299 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3301 = gen_rtx_MEM (save_mode,
3302 memory_address (save_mode,
3303 XEXP (args[i].stack_slot, 0)));
3305 if (save_mode != BLKmode)
3306 emit_move_insn (stack_area, args[i].save_area);
3308 emit_block_move (stack_area,
3309 validize_mem (args[i].save_area),
3310 GEN_INT (args[i].size.constant));
3313 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3314 stack_usage_map = initial_stack_usage_map;
3317 /* If this was alloca, record the new stack level for nonlocal gotos.
3318 Check for the handler slots since we might not have a save area
3319 for non-local gotos. */
3321 if ((flags & ECF_MAY_BE_ALLOCA) && nonlocal_goto_handler_slots != 0)
3322 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3326 /* Free up storage we no longer need. */
3327 for (i = 0; i < num_actuals; ++i)
3328 if (args[i].aligned_regs)
3329 free (args[i].aligned_regs);
3333 /* Undo the fake expand_start_target_temps we did earlier. If
3334 there had been any cleanups created, we've already set
3336 expand_end_target_temps ();
3339 insns = get_insns ();
3344 tail_call_insns = insns;
3346 /* Restore the pending stack adjustment now that we have
3347 finished generating the sibling call sequence. */
3349 pending_stack_adjust = save_pending_stack_adjust;
3350 stack_pointer_delta = save_stack_pointer_delta;
3352 /* Prepare arg structure for next iteration. */
3353 for (i = 0; i < num_actuals; i++)
3356 args[i].aligned_regs = 0;
3360 sbitmap_free (stored_args_map);
3363 normal_call_insns = insns;
3365 /* If something prevents making this a sibling call,
3366 zero out the sequence. */
3367 if (sibcall_failure)
3368 tail_call_insns = NULL_RTX;
3371 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3372 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3373 can happen if the arguments to this function call an inline
3374 function who's expansion contains another CALL_PLACEHOLDER.
3376 If there are any C_Ps in any of these sequences, replace them
3377 with their normal call. */
3379 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3380 if (GET_CODE (insn) == CALL_INSN
3381 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3382 replace_call_placeholder (insn, sibcall_use_normal);
3384 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
3385 if (GET_CODE (insn) == CALL_INSN
3386 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3387 replace_call_placeholder (insn, sibcall_use_normal);
3389 for (insn = tail_recursion_insns; insn; insn = NEXT_INSN (insn))
3390 if (GET_CODE (insn) == CALL_INSN
3391 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3392 replace_call_placeholder (insn, sibcall_use_normal);
3394 /* If this was a potential tail recursion site, then emit a
3395 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3396 One of them will be selected later. */
3397 if (tail_recursion_insns || tail_call_insns)
3399 /* The tail recursion label must be kept around. We could expose
3400 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3401 and makes determining true tail recursion sites difficult.
3403 So we set LABEL_PRESERVE_P here, then clear it when we select
3404 one of the call sequences after rtl generation is complete. */
3405 if (tail_recursion_insns)
3406 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3407 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3409 tail_recursion_insns,
3410 tail_recursion_label));
3413 emit_insns (normal_call_insns);
3415 currently_expanding_call--;
3417 /* If this function returns with the stack pointer depressed, ensure
3418 this block saves and restores the stack pointer, show it was
3419 changed, and adjust for any outgoing arg space. */
3420 if (flags & ECF_SP_DEPRESSED)
3422 clear_pending_stack_adjust ();
3423 emit_insn (gen_rtx (CLOBBER, VOIDmode, stack_pointer_rtx));
3424 emit_move_insn (virtual_stack_dynamic_rtx, stack_pointer_rtx);
3425 save_stack_pointer ();
3431 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3432 The RETVAL parameter specifies whether return value needs to be saved, other
3433 parameters are documented in the emit_library_call function below. */
3436 emit_library_call_value_1 (retval, orgfun, value, fn_type, outmode, nargs, p)
3440 enum libcall_type fn_type;
3441 enum machine_mode outmode;
3445 /* Total size in bytes of all the stack-parms scanned so far. */
3446 struct args_size args_size;
3447 /* Size of arguments before any adjustments (such as rounding). */
3448 struct args_size original_args_size;
3453 struct args_size alignment_pad;
3455 CUMULATIVE_ARGS args_so_far;
3459 enum machine_mode mode;
3462 struct args_size offset;
3463 struct args_size size;
3467 int old_inhibit_defer_pop = inhibit_defer_pop;
3468 rtx call_fusage = 0;
3471 int pcc_struct_value = 0;
3472 int struct_value_size = 0;
3474 int reg_parm_stack_space = 0;
3478 #ifdef REG_PARM_STACK_SPACE
3479 /* Define the boundary of the register parm stack space that needs to be
3481 int low_to_save = -1, high_to_save = 0;
3482 rtx save_area = 0; /* Place that it is saved. */
3485 /* Size of the stack reserved for parameter registers. */
3486 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3487 char *initial_stack_usage_map = stack_usage_map;
3489 #ifdef REG_PARM_STACK_SPACE
3490 #ifdef MAYBE_REG_PARM_STACK_SPACE
3491 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3493 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3497 /* By default, library functions can not throw. */
3498 flags = ECF_NOTHROW;
3505 /* Nothing to do here. */
3507 case LCT_CONST_MAKE_BLOCK:
3510 case LCT_PURE_MAKE_BLOCK:
3514 flags |= ECF_NORETURN;
3517 flags = ECF_NORETURN;
3519 case LCT_ALWAYS_RETURN:
3520 flags = ECF_ALWAYS_RETURN;
3522 case LCT_RETURNS_TWICE:
3523 flags = ECF_RETURNS_TWICE;
3528 /* Ensure current function's preferred stack boundary is at least
3530 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3531 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3533 /* If this kind of value comes back in memory,
3534 decide where in memory it should come back. */
3535 if (outmode != VOIDmode && aggregate_value_p (type_for_mode (outmode, 0)))
3537 #ifdef PCC_STATIC_STRUCT_RETURN
3539 = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
3541 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3542 pcc_struct_value = 1;
3544 value = gen_reg_rtx (outmode);
3545 #else /* not PCC_STATIC_STRUCT_RETURN */
3546 struct_value_size = GET_MODE_SIZE (outmode);
3547 if (value != 0 && GET_CODE (value) == MEM)
3550 mem_value = assign_temp (type_for_mode (outmode, 0), 0, 1, 1);
3553 /* This call returns a big structure. */
3554 flags &= ~(ECF_CONST | ECF_PURE);
3557 /* ??? Unfinished: must pass the memory address as an argument. */
3559 /* Copy all the libcall-arguments out of the varargs data
3560 and into a vector ARGVEC.
3562 Compute how to pass each argument. We only support a very small subset
3563 of the full argument passing conventions to limit complexity here since
3564 library functions shouldn't have many args. */
3566 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
3567 memset ((char *) argvec, 0, (nargs + 1) * sizeof (struct arg));
3569 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3570 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far, outmode, fun);
3572 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
3575 args_size.constant = 0;
3580 /* Now we are about to start emitting insns that can be deleted
3581 if a libcall is deleted. */
3582 if (flags & (ECF_CONST | ECF_PURE))
3587 /* If there's a structure value address to be passed,
3588 either pass it in the special place, or pass it as an extra argument. */
3589 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
3591 rtx addr = XEXP (mem_value, 0);
3594 /* Make sure it is a reasonable operand for a move or push insn. */
3595 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3596 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3597 addr = force_operand (addr, NULL_RTX);
3599 argvec[count].value = addr;
3600 argvec[count].mode = Pmode;
3601 argvec[count].partial = 0;
3603 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3604 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3605 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3609 locate_and_pad_parm (Pmode, NULL_TREE,
3610 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3613 argvec[count].reg != 0,
3615 NULL_TREE, &args_size, &argvec[count].offset,
3616 &argvec[count].size, &alignment_pad);
3618 if (argvec[count].reg == 0 || argvec[count].partial != 0
3619 || reg_parm_stack_space > 0)
3620 args_size.constant += argvec[count].size.constant;
3622 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3627 for (; count < nargs; count++)
3629 rtx val = va_arg (p, rtx);
3630 enum machine_mode mode = va_arg (p, enum machine_mode);
3632 /* We cannot convert the arg value to the mode the library wants here;
3633 must do it earlier where we know the signedness of the arg. */
3635 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3638 /* On some machines, there's no way to pass a float to a library fcn.
3639 Pass it as a double instead. */
3640 #ifdef LIBGCC_NEEDS_DOUBLE
3641 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
3642 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
3645 /* There's no need to call protect_from_queue, because
3646 either emit_move_insn or emit_push_insn will do that. */
3648 /* Make sure it is a reasonable operand for a move or push insn. */
3649 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3650 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3651 val = force_operand (val, NULL_RTX);
3653 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3654 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3658 #ifdef FUNCTION_ARG_CALLEE_COPIES
3659 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far, mode,
3664 if (GET_MODE (val) == MEM && ! must_copy)
3668 slot = assign_temp (type_for_mode (mode, 0), 0, 1, 1);
3669 emit_move_insn (slot, val);
3673 tree type = type_for_mode (mode, 0);
3675 slot = gen_rtx_MEM (mode,
3676 expand_expr (build1 (ADDR_EXPR,
3679 make_tree (type, val)),
3680 NULL_RTX, VOIDmode, 0));
3683 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3684 gen_rtx_USE (VOIDmode, slot),
3687 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3688 gen_rtx_CLOBBER (VOIDmode,
3693 val = force_operand (XEXP (slot, 0), NULL_RTX);
3697 argvec[count].value = val;
3698 argvec[count].mode = mode;
3700 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3702 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3703 argvec[count].partial
3704 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3706 argvec[count].partial = 0;
3709 locate_and_pad_parm (mode, NULL_TREE,
3710 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3713 argvec[count].reg != 0,
3715 NULL_TREE, &args_size, &argvec[count].offset,
3716 &argvec[count].size, &alignment_pad);
3718 if (argvec[count].size.var)
3721 if (reg_parm_stack_space == 0 && argvec[count].partial)
3722 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
3724 if (argvec[count].reg == 0 || argvec[count].partial != 0
3725 || reg_parm_stack_space > 0)
3726 args_size.constant += argvec[count].size.constant;
3728 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3731 #ifdef FINAL_REG_PARM_STACK_SPACE
3732 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3735 /* If this machine requires an external definition for library
3736 functions, write one out. */
3737 assemble_external_libcall (fun);
3739 original_args_size = args_size;
3740 args_size.constant = (((args_size.constant
3741 + stack_pointer_delta
3745 - stack_pointer_delta);
3747 args_size.constant = MAX (args_size.constant,
3748 reg_parm_stack_space);
3750 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3751 args_size.constant -= reg_parm_stack_space;
3754 if (args_size.constant > current_function_outgoing_args_size)
3755 current_function_outgoing_args_size = args_size.constant;
3757 if (ACCUMULATE_OUTGOING_ARGS)
3759 /* Since the stack pointer will never be pushed, it is possible for
3760 the evaluation of a parm to clobber something we have already
3761 written to the stack. Since most function calls on RISC machines
3762 do not use the stack, this is uncommon, but must work correctly.
3764 Therefore, we save any area of the stack that was already written
3765 and that we are using. Here we set up to do this by making a new
3766 stack usage map from the old one.
3768 Another approach might be to try to reorder the argument
3769 evaluations to avoid this conflicting stack usage. */
3771 needed = args_size.constant;
3773 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3774 /* Since we will be writing into the entire argument area, the
3775 map must be allocated for its entire size, not just the part that
3776 is the responsibility of the caller. */
3777 needed += reg_parm_stack_space;
3780 #ifdef ARGS_GROW_DOWNWARD
3781 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3784 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3787 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
3789 if (initial_highest_arg_in_use)
3790 memcpy (stack_usage_map, initial_stack_usage_map,
3791 initial_highest_arg_in_use);
3793 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3794 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3795 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3798 /* We must be careful to use virtual regs before they're instantiated,
3799 and real regs afterwards. Loop optimization, for example, can create
3800 new libcalls after we've instantiated the virtual regs, and if we
3801 use virtuals anyway, they won't match the rtl patterns. */
3803 if (virtuals_instantiated)
3804 argblock = plus_constant (stack_pointer_rtx, STACK_POINTER_OFFSET);
3806 argblock = virtual_outgoing_args_rtx;
3811 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3814 /* If we push args individually in reverse order, perform stack alignment
3815 before the first push (the last arg). */
3816 if (argblock == 0 && PUSH_ARGS_REVERSED)
3817 anti_adjust_stack (GEN_INT (args_size.constant
3818 - original_args_size.constant));
3820 if (PUSH_ARGS_REVERSED)
3831 #ifdef REG_PARM_STACK_SPACE
3832 if (ACCUMULATE_OUTGOING_ARGS)
3834 /* The argument list is the property of the called routine and it
3835 may clobber it. If the fixed area has been used for previous
3836 parameters, we must save and restore it.
3838 Here we compute the boundary of the that needs to be saved, if any. */
3840 #ifdef ARGS_GROW_DOWNWARD
3841 for (count = 0; count < reg_parm_stack_space + 1; count++)
3843 for (count = 0; count < reg_parm_stack_space; count++)
3846 if (count >= highest_outgoing_arg_in_use
3847 || stack_usage_map[count] == 0)
3850 if (low_to_save == -1)
3851 low_to_save = count;
3853 high_to_save = count;
3856 if (low_to_save >= 0)
3858 int num_to_save = high_to_save - low_to_save + 1;
3859 enum machine_mode save_mode
3860 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
3863 /* If we don't have the required alignment, must do this in BLKmode. */
3864 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
3865 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
3866 save_mode = BLKmode;
3868 #ifdef ARGS_GROW_DOWNWARD
3869 stack_area = gen_rtx_MEM (save_mode,
3870 memory_address (save_mode,
3871 plus_constant (argblock,
3874 stack_area = gen_rtx_MEM (save_mode,
3875 memory_address (save_mode,
3876 plus_constant (argblock,
3879 if (save_mode == BLKmode)
3881 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
3882 set_mem_align (save_area, PARM_BOUNDARY);
3883 emit_block_move (validize_mem (save_area), stack_area,
3884 GEN_INT (num_to_save));
3888 save_area = gen_reg_rtx (save_mode);
3889 emit_move_insn (save_area, stack_area);
3895 /* Push the args that need to be pushed. */
3897 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3898 are to be pushed. */
3899 for (count = 0; count < nargs; count++, argnum += inc)
3901 enum machine_mode mode = argvec[argnum].mode;
3902 rtx val = argvec[argnum].value;
3903 rtx reg = argvec[argnum].reg;
3904 int partial = argvec[argnum].partial;
3905 int lower_bound = 0, upper_bound = 0, i;
3907 if (! (reg != 0 && partial == 0))
3909 if (ACCUMULATE_OUTGOING_ARGS)
3911 /* If this is being stored into a pre-allocated, fixed-size,
3912 stack area, save any previous data at that location. */
3914 #ifdef ARGS_GROW_DOWNWARD
3915 /* stack_slot is negative, but we want to index stack_usage_map
3916 with positive values. */
3917 upper_bound = -argvec[argnum].offset.constant + 1;
3918 lower_bound = upper_bound - argvec[argnum].size.constant;
3920 lower_bound = argvec[argnum].offset.constant;
3921 upper_bound = lower_bound + argvec[argnum].size.constant;
3924 for (i = lower_bound; i < upper_bound; i++)
3925 if (stack_usage_map[i]
3926 /* Don't store things in the fixed argument area at this
3927 point; it has already been saved. */
3928 && i > reg_parm_stack_space)
3931 if (i != upper_bound)
3933 /* We need to make a save area. See what mode we can make
3935 enum machine_mode save_mode
3936 = mode_for_size (argvec[argnum].size.constant
3944 plus_constant (argblock,
3945 argvec[argnum].offset.constant)));
3946 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3948 emit_move_insn (argvec[argnum].save_area, stack_area);
3952 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
3953 argblock, GEN_INT (argvec[argnum].offset.constant),
3954 reg_parm_stack_space, ARGS_SIZE_RTX (alignment_pad));
3956 /* Now mark the segment we just used. */
3957 if (ACCUMULATE_OUTGOING_ARGS)
3958 for (i = lower_bound; i < upper_bound; i++)
3959 stack_usage_map[i] = 1;
3965 /* If we pushed args in forward order, perform stack alignment
3966 after pushing the last arg. */
3967 if (argblock == 0 && !PUSH_ARGS_REVERSED)
3968 anti_adjust_stack (GEN_INT (args_size.constant
3969 - original_args_size.constant));
3971 if (PUSH_ARGS_REVERSED)
3976 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0, 0);
3978 /* Now load any reg parms into their regs. */
3980 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3981 are to be pushed. */
3982 for (count = 0; count < nargs; count++, argnum += inc)
3984 rtx val = argvec[argnum].value;
3985 rtx reg = argvec[argnum].reg;
3986 int partial = argvec[argnum].partial;
3988 /* Handle calls that pass values in multiple non-contiguous
3989 locations. The PA64 has examples of this for library calls. */
3990 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3991 emit_group_load (reg, val, GET_MODE_SIZE (GET_MODE (val)));
3992 else if (reg != 0 && partial == 0)
3993 emit_move_insn (reg, val);
3998 /* Any regs containing parms remain in use through the call. */
3999 for (count = 0; count < nargs; count++)
4001 rtx reg = argvec[count].reg;
4002 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4003 use_group_regs (&call_fusage, reg);
4005 use_reg (&call_fusage, reg);
4008 /* Pass the function the address in which to return a structure value. */
4009 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
4011 emit_move_insn (struct_value_rtx,
4013 force_operand (XEXP (mem_value, 0),
4015 if (GET_CODE (struct_value_rtx) == REG)
4016 use_reg (&call_fusage, struct_value_rtx);
4019 /* Don't allow popping to be deferred, since then
4020 cse'ing of library calls could delete a call and leave the pop. */
4022 valreg = (mem_value == 0 && outmode != VOIDmode
4023 ? hard_libcall_value (outmode) : NULL_RTX);
4025 /* Stack must be properly aligned now. */
4026 if (stack_pointer_delta & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1))
4029 before_call = get_last_insn ();
4031 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4032 will set inhibit_defer_pop to that value. */
4033 /* The return type is needed to decide how many bytes the function pops.
4034 Signedness plays no role in that, so for simplicity, we pretend it's
4035 always signed. We also assume that the list of arguments passed has
4036 no impact, so we pretend it is unknown. */
4039 get_identifier (XSTR (orgfun, 0)),
4040 build_function_type (outmode == VOIDmode ? void_type_node
4041 : type_for_mode (outmode, 0), NULL_TREE),
4042 original_args_size.constant, args_size.constant,
4044 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
4046 old_inhibit_defer_pop + 1, call_fusage, flags);
4048 /* For calls to `setjmp', etc., inform flow.c it should complain
4049 if nonvolatile values are live. For functions that cannot return,
4050 inform flow that control does not fall through. */
4052 if (flags & (ECF_NORETURN | ECF_LONGJMP))
4054 /* The barrier note must be emitted
4055 immediately after the CALL_INSN. Some ports emit more than
4056 just a CALL_INSN above, so we must search for it here. */
4058 rtx last = get_last_insn ();
4059 while (GET_CODE (last) != CALL_INSN)
4061 last = PREV_INSN (last);
4062 /* There was no CALL_INSN? */
4063 if (last == before_call)
4067 emit_barrier_after (last);
4070 /* Now restore inhibit_defer_pop to its actual original value. */
4073 /* If call is cse'able, make appropriate pair of reg-notes around it.
4074 Test valreg so we don't crash; may safely ignore `const'
4075 if return type is void. Disable for PARALLEL return values, because
4076 we have no way to move such values into a pseudo register. */
4077 if ((flags & (ECF_CONST | ECF_PURE))
4078 && valreg != 0 && GET_CODE (valreg) != PARALLEL)
4081 rtx temp = gen_reg_rtx (GET_MODE (valreg));
4085 /* Construct an "equal form" for the value which mentions all the
4086 arguments in order as well as the function name. */
4087 for (i = 0; i < nargs; i++)
4088 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
4089 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
4091 insns = get_insns ();
4094 if (flags & ECF_PURE)
4095 note = gen_rtx_EXPR_LIST (VOIDmode,
4096 gen_rtx_USE (VOIDmode,
4097 gen_rtx_MEM (BLKmode,
4098 gen_rtx_SCRATCH (VOIDmode))), note);
4100 emit_libcall_block (insns, temp, valreg, note);
4104 else if (flags & (ECF_CONST | ECF_PURE))
4106 /* Otherwise, just write out the sequence without a note. */
4107 rtx insns = get_insns ();
4114 /* Copy the value to the right place. */
4115 if (outmode != VOIDmode && retval)
4121 if (value != mem_value)
4122 emit_move_insn (value, mem_value);
4124 else if (value != 0)
4125 emit_move_insn (value, hard_libcall_value (outmode));
4127 value = hard_libcall_value (outmode);
4130 if (ACCUMULATE_OUTGOING_ARGS)
4132 #ifdef REG_PARM_STACK_SPACE
4135 enum machine_mode save_mode = GET_MODE (save_area);
4136 #ifdef ARGS_GROW_DOWNWARD
4138 = gen_rtx_MEM (save_mode,
4139 memory_address (save_mode,
4140 plus_constant (argblock,
4144 = gen_rtx_MEM (save_mode,
4145 memory_address (save_mode,
4146 plus_constant (argblock, low_to_save)));
4149 set_mem_align (stack_area, PARM_BOUNDARY);
4150 if (save_mode != BLKmode)
4151 emit_move_insn (stack_area, save_area);
4153 emit_block_move (stack_area, validize_mem (save_area),
4154 GEN_INT (high_to_save - low_to_save + 1));
4158 /* If we saved any argument areas, restore them. */
4159 for (count = 0; count < nargs; count++)
4160 if (argvec[count].save_area)
4162 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4164 = gen_rtx_MEM (save_mode,
4167 plus_constant (argblock,
4168 argvec[count].offset.constant)));
4170 emit_move_insn (stack_area, argvec[count].save_area);
4173 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4174 stack_usage_map = initial_stack_usage_map;
4181 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4182 (emitting the queue unless NO_QUEUE is nonzero),
4183 for a value of mode OUTMODE,
4184 with NARGS different arguments, passed as alternating rtx values
4185 and machine_modes to convert them to.
4186 The rtx values should have been passed through protect_from_queue already.
4188 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4189 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4190 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4191 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4192 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4193 or other LCT_ value for other types of library calls. */
4196 emit_library_call VPARAMS((rtx orgfun, enum libcall_type fn_type,
4197 enum machine_mode outmode, int nargs, ...))
4200 VA_FIXEDARG (p, rtx, orgfun);
4201 VA_FIXEDARG (p, int, fn_type);
4202 VA_FIXEDARG (p, enum machine_mode, outmode);
4203 VA_FIXEDARG (p, int, nargs);
4205 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4210 /* Like emit_library_call except that an extra argument, VALUE,
4211 comes second and says where to store the result.
4212 (If VALUE is zero, this function chooses a convenient way
4213 to return the value.
4215 This function returns an rtx for where the value is to be found.
4216 If VALUE is nonzero, VALUE is returned. */
4219 emit_library_call_value VPARAMS((rtx orgfun, rtx value,
4220 enum libcall_type fn_type,
4221 enum machine_mode outmode, int nargs, ...))
4226 VA_FIXEDARG (p, rtx, orgfun);
4227 VA_FIXEDARG (p, rtx, value);
4228 VA_FIXEDARG (p, int, fn_type);
4229 VA_FIXEDARG (p, enum machine_mode, outmode);
4230 VA_FIXEDARG (p, int, nargs);
4232 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4240 /* Store a single argument for a function call
4241 into the register or memory area where it must be passed.
4242 *ARG describes the argument value and where to pass it.
4244 ARGBLOCK is the address of the stack-block for all the arguments,
4245 or 0 on a machine where arguments are pushed individually.
4247 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4248 so must be careful about how the stack is used.
4250 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4251 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4252 that we need not worry about saving and restoring the stack.
4254 FNDECL is the declaration of the function we are calling.
4256 Return non-zero if this arg should cause sibcall failure,
4260 store_one_arg (arg, argblock, flags, variable_size, reg_parm_stack_space)
4261 struct arg_data *arg;
4264 int variable_size ATTRIBUTE_UNUSED;
4265 int reg_parm_stack_space;
4267 tree pval = arg->tree_value;
4271 int i, lower_bound = 0, upper_bound = 0;
4272 int sibcall_failure = 0;
4274 if (TREE_CODE (pval) == ERROR_MARK)
4277 /* Push a new temporary level for any temporaries we make for
4281 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4283 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4284 save any previous data at that location. */
4285 if (argblock && ! variable_size && arg->stack)
4287 #ifdef ARGS_GROW_DOWNWARD
4288 /* stack_slot is negative, but we want to index stack_usage_map
4289 with positive values. */
4290 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4291 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4295 lower_bound = upper_bound - arg->size.constant;
4297 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4298 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4302 upper_bound = lower_bound + arg->size.constant;
4305 for (i = lower_bound; i < upper_bound; i++)
4306 if (stack_usage_map[i]
4307 /* Don't store things in the fixed argument area at this point;
4308 it has already been saved. */
4309 && i > reg_parm_stack_space)
4312 if (i != upper_bound)
4314 /* We need to make a save area. See what mode we can make it. */
4315 enum machine_mode save_mode
4316 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
4318 = gen_rtx_MEM (save_mode,
4319 memory_address (save_mode,
4320 XEXP (arg->stack_slot, 0)));
4322 if (save_mode == BLKmode)
4324 tree ot = TREE_TYPE (arg->tree_value);
4325 tree nt = build_qualified_type (ot, (TYPE_QUALS (ot)
4326 | TYPE_QUAL_CONST));
4328 arg->save_area = assign_temp (nt, 0, 1, 1);
4329 preserve_temp_slots (arg->save_area);
4330 emit_block_move (validize_mem (arg->save_area), stack_area,
4331 expr_size (arg->tree_value));
4335 arg->save_area = gen_reg_rtx (save_mode);
4336 emit_move_insn (arg->save_area, stack_area);
4340 /* Now that we have saved any slots that will be overwritten by this
4341 store, mark all slots this store will use. We must do this before
4342 we actually expand the argument since the expansion itself may
4343 trigger library calls which might need to use the same stack slot. */
4344 if (argblock && ! variable_size && arg->stack)
4345 for (i = lower_bound; i < upper_bound; i++)
4346 stack_usage_map[i] = 1;
4349 /* If this isn't going to be placed on both the stack and in registers,
4350 set up the register and number of words. */
4351 if (! arg->pass_on_stack)
4352 reg = arg->reg, partial = arg->partial;
4354 if (reg != 0 && partial == 0)
4355 /* Being passed entirely in a register. We shouldn't be called in
4359 /* If this arg needs special alignment, don't load the registers
4361 if (arg->n_aligned_regs != 0)
4364 /* If this is being passed partially in a register, we can't evaluate
4365 it directly into its stack slot. Otherwise, we can. */
4366 if (arg->value == 0)
4368 /* stack_arg_under_construction is nonzero if a function argument is
4369 being evaluated directly into the outgoing argument list and
4370 expand_call must take special action to preserve the argument list
4371 if it is called recursively.
4373 For scalar function arguments stack_usage_map is sufficient to
4374 determine which stack slots must be saved and restored. Scalar
4375 arguments in general have pass_on_stack == 0.
4377 If this argument is initialized by a function which takes the
4378 address of the argument (a C++ constructor or a C function
4379 returning a BLKmode structure), then stack_usage_map is
4380 insufficient and expand_call must push the stack around the
4381 function call. Such arguments have pass_on_stack == 1.
4383 Note that it is always safe to set stack_arg_under_construction,
4384 but this generates suboptimal code if set when not needed. */
4386 if (arg->pass_on_stack)
4387 stack_arg_under_construction++;
4389 arg->value = expand_expr (pval,
4391 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4392 ? NULL_RTX : arg->stack,
4395 /* If we are promoting object (or for any other reason) the mode
4396 doesn't agree, convert the mode. */
4398 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4399 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4400 arg->value, arg->unsignedp);
4402 if (arg->pass_on_stack)
4403 stack_arg_under_construction--;
4406 /* Don't allow anything left on stack from computation
4407 of argument to alloca. */
4408 if (flags & ECF_MAY_BE_ALLOCA)
4409 do_pending_stack_adjust ();
4411 if (arg->value == arg->stack)
4412 /* If the value is already in the stack slot, we are done. */
4414 else if (arg->mode != BLKmode)
4418 /* Argument is a scalar, not entirely passed in registers.
4419 (If part is passed in registers, arg->partial says how much
4420 and emit_push_insn will take care of putting it there.)
4422 Push it, and if its size is less than the
4423 amount of space allocated to it,
4424 also bump stack pointer by the additional space.
4425 Note that in C the default argument promotions
4426 will prevent such mismatches. */
4428 size = GET_MODE_SIZE (arg->mode);
4429 /* Compute how much space the push instruction will push.
4430 On many machines, pushing a byte will advance the stack
4431 pointer by a halfword. */
4432 #ifdef PUSH_ROUNDING
4433 size = PUSH_ROUNDING (size);
4437 /* Compute how much space the argument should get:
4438 round up to a multiple of the alignment for arguments. */
4439 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4440 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4441 / (PARM_BOUNDARY / BITS_PER_UNIT))
4442 * (PARM_BOUNDARY / BITS_PER_UNIT));
4444 /* This isn't already where we want it on the stack, so put it there.
4445 This can either be done with push or copy insns. */
4446 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX, 0,
4447 partial, reg, used - size, argblock,
4448 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
4449 ARGS_SIZE_RTX (arg->alignment_pad));
4453 /* BLKmode, at least partly to be pushed. */
4458 /* Pushing a nonscalar.
4459 If part is passed in registers, PARTIAL says how much
4460 and emit_push_insn will take care of putting it there. */
4462 /* Round its size up to a multiple
4463 of the allocation unit for arguments. */
4465 if (arg->size.var != 0)
4468 size_rtx = ARGS_SIZE_RTX (arg->size);
4472 /* PUSH_ROUNDING has no effect on us, because
4473 emit_push_insn for BLKmode is careful to avoid it. */
4474 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
4475 + partial * UNITS_PER_WORD);
4476 size_rtx = expr_size (pval);
4479 if ((flags & ECF_SIBCALL) && GET_CODE (arg->value) == MEM)
4481 /* emit_push_insn might not work properly if arg->value and
4482 argblock + arg->offset areas overlap. */
4486 if (XEXP (x, 0) == current_function_internal_arg_pointer
4487 || (GET_CODE (XEXP (x, 0)) == PLUS
4488 && XEXP (XEXP (x, 0), 0) ==
4489 current_function_internal_arg_pointer
4490 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT))
4492 if (XEXP (x, 0) != current_function_internal_arg_pointer)
4493 i = INTVAL (XEXP (XEXP (x, 0), 1));
4495 /* expand_call should ensure this */
4496 if (arg->offset.var || GET_CODE (size_rtx) != CONST_INT)
4499 if (arg->offset.constant > i)
4501 if (arg->offset.constant < i + INTVAL (size_rtx))
4502 sibcall_failure = 1;
4504 else if (arg->offset.constant < i)
4506 if (i < arg->offset.constant + INTVAL (size_rtx))
4507 sibcall_failure = 1;
4512 /* Special handling is required if part of the parameter lies in the
4513 register parameter area. The argument may be copied into the stack
4514 slot using memcpy(), but the original contents of the register
4515 parameter area will be restored after the memcpy() call.
4517 To ensure that the part that lies in the register parameter area
4518 is copied correctly, we emit a separate push for that part. This
4519 push should be small enough to avoid a call to memcpy(). */
4520 #ifndef STACK_PARMS_IN_REG_PARM_AREA
4521 if (arg->reg && arg->pass_on_stack)
4526 if (arg->offset.constant < reg_parm_stack_space && arg->offset.var)
4527 error ("variable offset is passed partially in stack and in reg");
4528 else if (arg->offset.constant < reg_parm_stack_space && arg->size.var)
4529 error ("variable size is passed partially in stack and in reg");
4530 else if (arg->offset.constant < reg_parm_stack_space
4531 && ((arg->offset.constant + arg->size.constant)
4532 > reg_parm_stack_space))
4534 rtx size_rtx1 = GEN_INT (reg_parm_stack_space - arg->offset.constant);
4535 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx1,
4536 TYPE_ALIGN (TREE_TYPE (pval)), partial, reg,
4537 excess, argblock, ARGS_SIZE_RTX (arg->offset),
4538 reg_parm_stack_space,
4539 ARGS_SIZE_RTX (arg->alignment_pad));
4544 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4545 TYPE_ALIGN (TREE_TYPE (pval)), partial, reg, excess,
4546 argblock, ARGS_SIZE_RTX (arg->offset),
4547 reg_parm_stack_space,
4548 ARGS_SIZE_RTX (arg->alignment_pad));
4551 /* Unless this is a partially-in-register argument, the argument is now
4554 ??? Note that this can change arg->value from arg->stack to
4555 arg->stack_slot and it matters when they are not the same.
4556 It isn't totally clear that this is correct in all cases. */
4558 arg->value = arg->stack_slot;
4560 /* Once we have pushed something, pops can't safely
4561 be deferred during the rest of the arguments. */
4564 /* ANSI doesn't require a sequence point here,
4565 but PCC has one, so this will avoid some problems. */
4568 /* Free any temporary slots made in processing this argument. Show
4569 that we might have taken the address of something and pushed that
4571 preserve_temp_slots (NULL_RTX);
4575 return sibcall_failure;