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);
1217 /* We make a copy of the object and pass the address to the
1218 function being called. */
1221 if (!COMPLETE_TYPE_P (type)
1222 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1223 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1224 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1225 STACK_CHECK_MAX_VAR_SIZE))))
1227 /* This is a variable-sized object. Make space on the stack
1229 rtx size_rtx = expr_size (TREE_VALUE (p));
1231 if (*old_stack_level == 0)
1233 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1234 *old_pending_adj = pending_stack_adjust;
1235 pending_stack_adjust = 0;
1238 copy = gen_rtx_MEM (BLKmode,
1239 allocate_dynamic_stack_space
1240 (size_rtx, NULL_RTX, TYPE_ALIGN (type)));
1241 set_mem_attributes (copy, type, 1);
1244 copy = assign_temp (type, 0, 1, 0);
1246 store_expr (args[i].tree_value, copy, 0);
1247 *ecf_flags &= ~(ECF_CONST | ECF_PURE);
1249 args[i].tree_value = build1 (ADDR_EXPR,
1250 build_pointer_type (type),
1251 make_tree (type, copy));
1252 type = build_pointer_type (type);
1256 mode = TYPE_MODE (type);
1257 unsignedp = TREE_UNSIGNED (type);
1259 #ifdef PROMOTE_FUNCTION_ARGS
1260 mode = promote_mode (type, mode, &unsignedp, 1);
1263 args[i].unsignedp = unsignedp;
1264 args[i].mode = mode;
1266 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1267 argpos < n_named_args);
1268 #ifdef FUNCTION_INCOMING_ARG
1269 /* If this is a sibling call and the machine has register windows, the
1270 register window has to be unwinded before calling the routine, so
1271 arguments have to go into the incoming registers. */
1272 args[i].tail_call_reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1273 argpos < n_named_args);
1275 args[i].tail_call_reg = args[i].reg;
1278 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1281 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1282 argpos < n_named_args);
1285 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1287 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1288 it means that we are to pass this arg in the register(s) designated
1289 by the PARALLEL, but also to pass it in the stack. */
1290 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1291 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1292 args[i].pass_on_stack = 1;
1294 /* If this is an addressable type, we must preallocate the stack
1295 since we must evaluate the object into its final location.
1297 If this is to be passed in both registers and the stack, it is simpler
1299 if (TREE_ADDRESSABLE (type)
1300 || (args[i].pass_on_stack && args[i].reg != 0))
1301 *must_preallocate = 1;
1303 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1304 we cannot consider this function call constant. */
1305 if (TREE_ADDRESSABLE (type))
1306 *ecf_flags &= ~(ECF_CONST | ECF_PURE);
1308 /* Compute the stack-size of this argument. */
1309 if (args[i].reg == 0 || args[i].partial != 0
1310 || reg_parm_stack_space > 0
1311 || args[i].pass_on_stack)
1312 locate_and_pad_parm (mode, type,
1313 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1318 fndecl, args_size, &args[i].offset,
1319 &args[i].size, &alignment_pad);
1321 #ifndef ARGS_GROW_DOWNWARD
1322 args[i].slot_offset = *args_size;
1325 args[i].alignment_pad = alignment_pad;
1327 /* If a part of the arg was put into registers,
1328 don't include that part in the amount pushed. */
1329 if (reg_parm_stack_space == 0 && ! args[i].pass_on_stack)
1330 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1331 / (PARM_BOUNDARY / BITS_PER_UNIT)
1332 * (PARM_BOUNDARY / BITS_PER_UNIT));
1334 /* Update ARGS_SIZE, the total stack space for args so far. */
1336 args_size->constant += args[i].size.constant;
1337 if (args[i].size.var)
1339 ADD_PARM_SIZE (*args_size, args[i].size.var);
1342 /* Since the slot offset points to the bottom of the slot,
1343 we must record it after incrementing if the args grow down. */
1344 #ifdef ARGS_GROW_DOWNWARD
1345 args[i].slot_offset = *args_size;
1347 args[i].slot_offset.constant = -args_size->constant;
1349 SUB_PARM_SIZE (args[i].slot_offset, args_size->var);
1352 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1353 have been used, etc. */
1355 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1356 argpos < n_named_args);
1360 /* Update ARGS_SIZE to contain the total size for the argument block.
1361 Return the original constant component of the argument block's size.
1363 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1364 for arguments passed in registers. */
1367 compute_argument_block_size (reg_parm_stack_space, args_size,
1368 preferred_stack_boundary)
1369 int reg_parm_stack_space;
1370 struct args_size *args_size;
1371 int preferred_stack_boundary ATTRIBUTE_UNUSED;
1373 int unadjusted_args_size = args_size->constant;
1375 /* For accumulate outgoing args mode we don't need to align, since the frame
1376 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1377 backends from generating misaligned frame sizes. */
1378 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1379 preferred_stack_boundary = STACK_BOUNDARY;
1381 /* Compute the actual size of the argument block required. The variable
1382 and constant sizes must be combined, the size may have to be rounded,
1383 and there may be a minimum required size. */
1387 args_size->var = ARGS_SIZE_TREE (*args_size);
1388 args_size->constant = 0;
1390 preferred_stack_boundary /= BITS_PER_UNIT;
1391 if (preferred_stack_boundary > 1)
1393 /* We don't handle this case yet. To handle it correctly we have
1394 to add the delta, round and subtract the delta.
1395 Currently no machine description requires this support. */
1396 if (stack_pointer_delta & (preferred_stack_boundary - 1))
1398 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1401 if (reg_parm_stack_space > 0)
1404 = size_binop (MAX_EXPR, args_size->var,
1405 ssize_int (reg_parm_stack_space));
1407 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1408 /* The area corresponding to register parameters is not to count in
1409 the size of the block we need. So make the adjustment. */
1411 = size_binop (MINUS_EXPR, args_size->var,
1412 ssize_int (reg_parm_stack_space));
1418 preferred_stack_boundary /= BITS_PER_UNIT;
1419 if (preferred_stack_boundary < 1)
1420 preferred_stack_boundary = 1;
1421 args_size->constant = (((args_size->constant
1422 + stack_pointer_delta
1423 + preferred_stack_boundary - 1)
1424 / preferred_stack_boundary
1425 * preferred_stack_boundary)
1426 - stack_pointer_delta);
1428 args_size->constant = MAX (args_size->constant,
1429 reg_parm_stack_space);
1431 #ifdef MAYBE_REG_PARM_STACK_SPACE
1432 if (reg_parm_stack_space == 0)
1433 args_size->constant = 0;
1436 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1437 args_size->constant -= reg_parm_stack_space;
1440 return unadjusted_args_size;
1443 /* Precompute parameters as needed for a function call.
1445 FLAGS is mask of ECF_* constants.
1447 NUM_ACTUALS is the number of arguments.
1449 ARGS is an array containing information for each argument; this
1450 routine fills in the INITIAL_VALUE and VALUE fields for each
1451 precomputed argument. */
1454 precompute_arguments (flags, num_actuals, args)
1457 struct arg_data *args;
1461 /* If this function call is cse'able, precompute all the parameters.
1462 Note that if the parameter is constructed into a temporary, this will
1463 cause an additional copy because the parameter will be constructed
1464 into a temporary location and then copied into the outgoing arguments.
1465 If a parameter contains a call to alloca and this function uses the
1466 stack, precompute the parameter. */
1468 /* If we preallocated the stack space, and some arguments must be passed
1469 on the stack, then we must precompute any parameter which contains a
1470 function call which will store arguments on the stack.
1471 Otherwise, evaluating the parameter may clobber previous parameters
1472 which have already been stored into the stack. (we have code to avoid
1473 such case by saving the outgoing stack arguments, but it results in
1476 for (i = 0; i < num_actuals; i++)
1477 if ((flags & (ECF_CONST | ECF_PURE))
1478 || calls_function (args[i].tree_value, !ACCUMULATE_OUTGOING_ARGS))
1480 enum machine_mode mode;
1482 /* If this is an addressable type, we cannot pre-evaluate it. */
1483 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1489 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1491 preserve_temp_slots (args[i].value);
1494 /* ANSI doesn't require a sequence point here,
1495 but PCC has one, so this will avoid some problems. */
1498 args[i].initial_value = args[i].value
1499 = protect_from_queue (args[i].value, 0);
1501 mode = TYPE_MODE (TREE_TYPE (args[i].tree_value));
1502 if (mode != args[i].mode)
1505 = convert_modes (args[i].mode, mode,
1506 args[i].value, args[i].unsignedp);
1507 #ifdef PROMOTE_FOR_CALL_ONLY
1508 /* CSE will replace this only if it contains args[i].value
1509 pseudo, so convert it down to the declared mode using
1511 if (GET_CODE (args[i].value) == REG
1512 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1514 args[i].initial_value
1515 = gen_lowpart_SUBREG (mode, args[i].value);
1516 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1517 SUBREG_PROMOTED_UNSIGNED_P (args[i].initial_value)
1518 = args[i].unsignedp;
1525 /* Given the current state of MUST_PREALLOCATE and information about
1526 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1527 compute and return the final value for MUST_PREALLOCATE. */
1530 finalize_must_preallocate (must_preallocate, num_actuals, args, args_size)
1531 int must_preallocate;
1533 struct arg_data *args;
1534 struct args_size *args_size;
1536 /* See if we have or want to preallocate stack space.
1538 If we would have to push a partially-in-regs parm
1539 before other stack parms, preallocate stack space instead.
1541 If the size of some parm is not a multiple of the required stack
1542 alignment, we must preallocate.
1544 If the total size of arguments that would otherwise create a copy in
1545 a temporary (such as a CALL) is more than half the total argument list
1546 size, preallocation is faster.
1548 Another reason to preallocate is if we have a machine (like the m88k)
1549 where stack alignment is required to be maintained between every
1550 pair of insns, not just when the call is made. However, we assume here
1551 that such machines either do not have push insns (and hence preallocation
1552 would occur anyway) or the problem is taken care of with
1555 if (! must_preallocate)
1557 int partial_seen = 0;
1558 int copy_to_evaluate_size = 0;
1561 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1563 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1565 else if (partial_seen && args[i].reg == 0)
1566 must_preallocate = 1;
1568 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1569 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1570 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1571 || TREE_CODE (args[i].tree_value) == COND_EXPR
1572 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1573 copy_to_evaluate_size
1574 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1577 if (copy_to_evaluate_size * 2 >= args_size->constant
1578 && args_size->constant > 0)
1579 must_preallocate = 1;
1581 return must_preallocate;
1584 /* If we preallocated stack space, compute the address of each argument
1585 and store it into the ARGS array.
1587 We need not ensure it is a valid memory address here; it will be
1588 validized when it is used.
1590 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1593 compute_argument_addresses (args, argblock, num_actuals)
1594 struct arg_data *args;
1600 rtx arg_reg = argblock;
1601 int i, arg_offset = 0;
1603 if (GET_CODE (argblock) == PLUS)
1604 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1606 for (i = 0; i < num_actuals; i++)
1608 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1609 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1612 /* Skip this parm if it will not be passed on the stack. */
1613 if (! args[i].pass_on_stack && args[i].reg != 0)
1616 if (GET_CODE (offset) == CONST_INT)
1617 addr = plus_constant (arg_reg, INTVAL (offset));
1619 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1621 addr = plus_constant (addr, arg_offset);
1622 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1623 set_mem_attributes (args[i].stack,
1624 TREE_TYPE (args[i].tree_value), 1);
1626 if (GET_CODE (slot_offset) == CONST_INT)
1627 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1629 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1631 addr = plus_constant (addr, arg_offset);
1632 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1633 set_mem_attributes (args[i].stack_slot,
1634 TREE_TYPE (args[i].tree_value), 1);
1636 /* Function incoming arguments may overlap with sibling call
1637 outgoing arguments and we cannot allow reordering of reads
1638 from function arguments with stores to outgoing arguments
1639 of sibling calls. */
1640 set_mem_alias_set (args[i].stack, 0);
1641 set_mem_alias_set (args[i].stack_slot, 0);
1646 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1647 in a call instruction.
1649 FNDECL is the tree node for the target function. For an indirect call
1650 FNDECL will be NULL_TREE.
1652 EXP is the CALL_EXPR for this call. */
1655 rtx_for_function_call (fndecl, exp)
1661 /* Get the function to call, in the form of RTL. */
1664 /* If this is the first use of the function, see if we need to
1665 make an external definition for it. */
1666 if (! TREE_USED (fndecl))
1668 assemble_external (fndecl);
1669 TREE_USED (fndecl) = 1;
1672 /* Get a SYMBOL_REF rtx for the function address. */
1673 funexp = XEXP (DECL_RTL (fndecl), 0);
1676 /* Generate an rtx (probably a pseudo-register) for the address. */
1681 = expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1682 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1688 /* Do the register loads required for any wholly-register parms or any
1689 parms which are passed both on the stack and in a register. Their
1690 expressions were already evaluated.
1692 Mark all register-parms as living through the call, putting these USE
1693 insns in the CALL_INSN_FUNCTION_USAGE field. */
1696 load_register_parameters (args, num_actuals, call_fusage, flags)
1697 struct arg_data *args;
1704 #ifdef LOAD_ARGS_REVERSED
1705 for (i = num_actuals - 1; i >= 0; i--)
1707 for (i = 0; i < num_actuals; i++)
1710 rtx reg = ((flags & ECF_SIBCALL)
1711 ? args[i].tail_call_reg : args[i].reg);
1712 int partial = args[i].partial;
1717 /* Set to non-negative if must move a word at a time, even if just
1718 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1719 we just use a normal move insn. This value can be zero if the
1720 argument is a zero size structure with no fields. */
1721 nregs = (partial ? partial
1722 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1723 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1724 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1727 /* Handle calls that pass values in multiple non-contiguous
1728 locations. The Irix 6 ABI has examples of this. */
1730 if (GET_CODE (reg) == PARALLEL)
1731 emit_group_load (reg, args[i].value,
1732 int_size_in_bytes (TREE_TYPE (args[i].tree_value)));
1734 /* If simple case, just do move. If normal partial, store_one_arg
1735 has already loaded the register for us. In all other cases,
1736 load the register(s) from memory. */
1738 else if (nregs == -1)
1739 emit_move_insn (reg, args[i].value);
1741 /* If we have pre-computed the values to put in the registers in
1742 the case of non-aligned structures, copy them in now. */
1744 else if (args[i].n_aligned_regs != 0)
1745 for (j = 0; j < args[i].n_aligned_regs; j++)
1746 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1747 args[i].aligned_regs[j]);
1749 else if (partial == 0 || args[i].pass_on_stack)
1750 move_block_to_reg (REGNO (reg),
1751 validize_mem (args[i].value), nregs,
1754 /* Handle calls that pass values in multiple non-contiguous
1755 locations. The Irix 6 ABI has examples of this. */
1756 if (GET_CODE (reg) == PARALLEL)
1757 use_group_regs (call_fusage, reg);
1758 else if (nregs == -1)
1759 use_reg (call_fusage, reg);
1761 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1766 /* Try to integrate function. See expand_inline_function for documentation
1767 about the parameters. */
1770 try_to_integrate (fndecl, actparms, target, ignore, type, structure_value_addr)
1776 rtx structure_value_addr;
1781 rtx old_stack_level = 0;
1782 int reg_parm_stack_space = 0;
1784 #ifdef REG_PARM_STACK_SPACE
1785 #ifdef MAYBE_REG_PARM_STACK_SPACE
1786 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1788 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1792 before_call = get_last_insn ();
1794 timevar_push (TV_INTEGRATION);
1796 temp = expand_inline_function (fndecl, actparms, target,
1798 structure_value_addr);
1800 timevar_pop (TV_INTEGRATION);
1802 /* If inlining succeeded, return. */
1803 if (temp != (rtx) (HOST_WIDE_INT) - 1)
1805 if (ACCUMULATE_OUTGOING_ARGS)
1807 /* If the outgoing argument list must be preserved, push
1808 the stack before executing the inlined function if it
1811 for (i = reg_parm_stack_space - 1; i >= 0; i--)
1812 if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
1815 if (stack_arg_under_construction || i >= 0)
1818 = before_call ? NEXT_INSN (before_call) : get_insns ();
1819 rtx insn = NULL_RTX, seq;
1821 /* Look for a call in the inline function code.
1822 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1823 nonzero then there is a call and it is not necessary
1824 to scan the insns. */
1826 if (DECL_SAVED_INSNS (fndecl)->outgoing_args_size == 0)
1827 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1828 if (GET_CODE (insn) == CALL_INSN)
1833 /* Reserve enough stack space so that the largest
1834 argument list of any function call in the inline
1835 function does not overlap the argument list being
1836 evaluated. This is usually an overestimate because
1837 allocate_dynamic_stack_space reserves space for an
1838 outgoing argument list in addition to the requested
1839 space, but there is no way to ask for stack space such
1840 that an argument list of a certain length can be
1843 Add the stack space reserved for register arguments, if
1844 any, in the inline function. What is really needed is the
1845 largest value of reg_parm_stack_space in the inline
1846 function, but that is not available. Using the current
1847 value of reg_parm_stack_space is wrong, but gives
1848 correct results on all supported machines. */
1850 int adjust = (DECL_SAVED_INSNS (fndecl)->outgoing_args_size
1851 + reg_parm_stack_space);
1854 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1855 allocate_dynamic_stack_space (GEN_INT (adjust),
1856 NULL_RTX, BITS_PER_UNIT);
1859 emit_insns_before (seq, first_insn);
1860 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1865 /* If the result is equivalent to TARGET, return TARGET to simplify
1866 checks in store_expr. They can be equivalent but not equal in the
1867 case of a function that returns BLKmode. */
1868 if (temp != target && rtx_equal_p (temp, target))
1873 /* If inlining failed, mark FNDECL as needing to be compiled
1874 separately after all. If function was declared inline,
1876 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1877 && optimize > 0 && !TREE_ADDRESSABLE (fndecl))
1879 warning_with_decl (fndecl, "inlining failed in call to `%s'");
1880 warning ("called from here");
1882 mark_addressable (fndecl);
1883 return (rtx) (HOST_WIDE_INT) - 1;
1886 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1887 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1888 bytes, then we would need to push some additional bytes to pad the
1889 arguments. So, we compute an adjust to the stack pointer for an
1890 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1891 bytes. Then, when the arguments are pushed the stack will be perfectly
1892 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1893 be popped after the call. Returns the adjustment. */
1896 combine_pending_stack_adjustment_and_call (unadjusted_args_size,
1898 preferred_unit_stack_boundary)
1899 int unadjusted_args_size;
1900 struct args_size *args_size;
1901 int preferred_unit_stack_boundary;
1903 /* The number of bytes to pop so that the stack will be
1904 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1905 HOST_WIDE_INT adjustment;
1906 /* The alignment of the stack after the arguments are pushed, if we
1907 just pushed the arguments without adjust the stack here. */
1908 HOST_WIDE_INT unadjusted_alignment;
1910 unadjusted_alignment
1911 = ((stack_pointer_delta + unadjusted_args_size)
1912 % preferred_unit_stack_boundary);
1914 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1915 as possible -- leaving just enough left to cancel out the
1916 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1917 PENDING_STACK_ADJUST is non-negative, and congruent to
1918 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1920 /* Begin by trying to pop all the bytes. */
1921 unadjusted_alignment
1922 = (unadjusted_alignment
1923 - (pending_stack_adjust % preferred_unit_stack_boundary));
1924 adjustment = pending_stack_adjust;
1925 /* Push enough additional bytes that the stack will be aligned
1926 after the arguments are pushed. */
1927 if (preferred_unit_stack_boundary > 1)
1929 if (unadjusted_alignment > 0)
1930 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1932 adjustment += unadjusted_alignment;
1935 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1936 bytes after the call. The right number is the entire
1937 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1938 by the arguments in the first place. */
1940 = pending_stack_adjust - adjustment + unadjusted_args_size;
1945 /* Scan X expression if it does not dereference any argument slots
1946 we already clobbered by tail call arguments (as noted in stored_args_map
1948 Return non-zero if X expression dereferences such argument slots,
1952 check_sibcall_argument_overlap_1 (x)
1963 code = GET_CODE (x);
1967 if (XEXP (x, 0) == current_function_internal_arg_pointer)
1969 else if (GET_CODE (XEXP (x, 0)) == PLUS
1970 && XEXP (XEXP (x, 0), 0) ==
1971 current_function_internal_arg_pointer
1972 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
1973 i = INTVAL (XEXP (XEXP (x, 0), 1));
1977 #ifdef ARGS_GROW_DOWNWARD
1978 i = -i - GET_MODE_SIZE (GET_MODE (x));
1981 for (k = 0; k < GET_MODE_SIZE (GET_MODE (x)); k++)
1982 if (i + k < stored_args_map->n_bits
1983 && TEST_BIT (stored_args_map, i + k))
1989 /* Scan all subexpressions. */
1990 fmt = GET_RTX_FORMAT (code);
1991 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
1995 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
1998 else if (*fmt == 'E')
2000 for (j = 0; j < XVECLEN (x, i); j++)
2001 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2008 /* Scan sequence after INSN if it does not dereference any argument slots
2009 we already clobbered by tail call arguments (as noted in stored_args_map
2010 bitmap). Add stack slots for ARG to stored_args_map bitmap afterwards.
2011 Return non-zero if sequence after INSN dereferences such argument slots,
2015 check_sibcall_argument_overlap (insn, arg)
2017 struct arg_data *arg;
2021 if (insn == NULL_RTX)
2022 insn = get_insns ();
2024 insn = NEXT_INSN (insn);
2026 for (; insn; insn = NEXT_INSN (insn))
2028 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2031 #ifdef ARGS_GROW_DOWNWARD
2032 low = -arg->slot_offset.constant - arg->size.constant;
2034 low = arg->slot_offset.constant;
2037 for (high = low + arg->size.constant; low < high; low++)
2038 SET_BIT (stored_args_map, low);
2039 return insn != NULL_RTX;
2042 /* Generate all the code for a function call
2043 and return an rtx for its value.
2044 Store the value in TARGET (specified as an rtx) if convenient.
2045 If the value is stored in TARGET then TARGET is returned.
2046 If IGNORE is nonzero, then we ignore the value of the function call. */
2049 expand_call (exp, target, ignore)
2054 /* Nonzero if we are currently expanding a call. */
2055 static int currently_expanding_call = 0;
2057 /* List of actual parameters. */
2058 tree actparms = TREE_OPERAND (exp, 1);
2059 /* RTX for the function to be called. */
2061 /* Sequence of insns to perform a tail recursive "call". */
2062 rtx tail_recursion_insns = NULL_RTX;
2063 /* Sequence of insns to perform a normal "call". */
2064 rtx normal_call_insns = NULL_RTX;
2065 /* Sequence of insns to perform a tail recursive "call". */
2066 rtx tail_call_insns = NULL_RTX;
2067 /* Data type of the function. */
2069 /* Declaration of the function being called,
2070 or 0 if the function is computed (not known by name). */
2073 int try_tail_call = 1;
2074 int try_tail_recursion = 1;
2077 /* Register in which non-BLKmode value will be returned,
2078 or 0 if no value or if value is BLKmode. */
2080 /* Address where we should return a BLKmode value;
2081 0 if value not BLKmode. */
2082 rtx structure_value_addr = 0;
2083 /* Nonzero if that address is being passed by treating it as
2084 an extra, implicit first parameter. Otherwise,
2085 it is passed by being copied directly into struct_value_rtx. */
2086 int structure_value_addr_parm = 0;
2087 /* Size of aggregate value wanted, or zero if none wanted
2088 or if we are using the non-reentrant PCC calling convention
2089 or expecting the value in registers. */
2090 HOST_WIDE_INT struct_value_size = 0;
2091 /* Nonzero if called function returns an aggregate in memory PCC style,
2092 by returning the address of where to find it. */
2093 int pcc_struct_value = 0;
2095 /* Number of actual parameters in this call, including struct value addr. */
2097 /* Number of named args. Args after this are anonymous ones
2098 and they must all go on the stack. */
2101 /* Vector of information about each argument.
2102 Arguments are numbered in the order they will be pushed,
2103 not the order they are written. */
2104 struct arg_data *args;
2106 /* Total size in bytes of all the stack-parms scanned so far. */
2107 struct args_size args_size;
2108 struct args_size adjusted_args_size;
2109 /* Size of arguments before any adjustments (such as rounding). */
2110 int unadjusted_args_size;
2111 /* Data on reg parms scanned so far. */
2112 CUMULATIVE_ARGS args_so_far;
2113 /* Nonzero if a reg parm has been scanned. */
2115 /* Nonzero if this is an indirect function call. */
2117 /* Nonzero if we must avoid push-insns in the args for this call.
2118 If stack space is allocated for register parameters, but not by the
2119 caller, then it is preallocated in the fixed part of the stack frame.
2120 So the entire argument block must then be preallocated (i.e., we
2121 ignore PUSH_ROUNDING in that case). */
2123 int must_preallocate = !PUSH_ARGS;
2125 /* Size of the stack reserved for parameter registers. */
2126 int reg_parm_stack_space = 0;
2128 /* Address of space preallocated for stack parms
2129 (on machines that lack push insns), or 0 if space not preallocated. */
2132 /* Mask of ECF_ flags. */
2134 /* Nonzero if this is a call to an inline function. */
2135 int is_integrable = 0;
2136 #ifdef REG_PARM_STACK_SPACE
2137 /* Define the boundary of the register parm stack space that needs to be
2139 int low_to_save = -1, high_to_save;
2140 rtx save_area = 0; /* Place that it is saved */
2143 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2144 char *initial_stack_usage_map = stack_usage_map;
2145 int old_stack_arg_under_construction = 0;
2147 rtx old_stack_level = 0;
2148 int old_pending_adj = 0;
2149 int old_inhibit_defer_pop = inhibit_defer_pop;
2150 int old_stack_allocated;
2152 tree p = TREE_OPERAND (exp, 0);
2154 /* The alignment of the stack, in bits. */
2155 HOST_WIDE_INT preferred_stack_boundary;
2156 /* The alignment of the stack, in bytes. */
2157 HOST_WIDE_INT preferred_unit_stack_boundary;
2159 /* See if this is "nothrow" function call. */
2160 if (TREE_NOTHROW (exp))
2161 flags |= ECF_NOTHROW;
2163 /* See if we can find a DECL-node for the actual function.
2164 As a result, decide whether this is a call to an integrable function. */
2166 fndecl = get_callee_fndecl (exp);
2170 && fndecl != current_function_decl
2171 && DECL_INLINE (fndecl)
2172 && DECL_SAVED_INSNS (fndecl)
2173 && DECL_SAVED_INSNS (fndecl)->inlinable)
2175 else if (! TREE_ADDRESSABLE (fndecl))
2177 /* In case this function later becomes inlinable,
2178 record that there was already a non-inline call to it.
2180 Use abstraction instead of setting TREE_ADDRESSABLE
2182 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2185 warning_with_decl (fndecl, "can't inline call to `%s'");
2186 warning ("called from here");
2188 mark_addressable (fndecl);
2191 flags |= flags_from_decl_or_type (fndecl);
2194 /* If we don't have specific function to call, see if we have a
2195 attributes set in the type. */
2197 flags |= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p)));
2199 /* Mark if the function returns with the stack pointer depressed. */
2200 if (TREE_CODE (TREE_TYPE (TREE_TYPE (p))) == FUNCTION_TYPE
2201 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (TREE_TYPE (p))))
2203 flags |= ECF_SP_DEPRESSED;
2204 flags &= ~(ECF_PURE | ECF_CONST);
2207 #ifdef REG_PARM_STACK_SPACE
2208 #ifdef MAYBE_REG_PARM_STACK_SPACE
2209 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
2211 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2215 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2216 if (reg_parm_stack_space > 0 && PUSH_ARGS)
2217 must_preallocate = 1;
2220 /* Warn if this value is an aggregate type,
2221 regardless of which calling convention we are using for it. */
2222 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2223 warning ("function call has aggregate value");
2225 /* Set up a place to return a structure. */
2227 /* Cater to broken compilers. */
2228 if (aggregate_value_p (exp))
2230 /* This call returns a big structure. */
2231 flags &= ~(ECF_CONST | ECF_PURE);
2233 #ifdef PCC_STATIC_STRUCT_RETURN
2235 pcc_struct_value = 1;
2236 /* Easier than making that case work right. */
2239 /* In case this is a static function, note that it has been
2241 if (! TREE_ADDRESSABLE (fndecl))
2242 mark_addressable (fndecl);
2246 #else /* not PCC_STATIC_STRUCT_RETURN */
2248 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2250 if (target && GET_CODE (target) == MEM)
2251 structure_value_addr = XEXP (target, 0);
2254 /* For variable-sized objects, we must be called with a target
2255 specified. If we were to allocate space on the stack here,
2256 we would have no way of knowing when to free it. */
2257 rtx d = assign_temp (TREE_TYPE (exp), 1, 1, 1);
2259 mark_temp_addr_taken (d);
2260 structure_value_addr = XEXP (d, 0);
2264 #endif /* not PCC_STATIC_STRUCT_RETURN */
2267 /* If called function is inline, try to integrate it. */
2271 rtx temp = try_to_integrate (fndecl, actparms, target,
2272 ignore, TREE_TYPE (exp),
2273 structure_value_addr);
2274 if (temp != (rtx) (HOST_WIDE_INT) - 1)
2278 /* Figure out the amount to which the stack should be aligned. */
2279 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2281 /* Operand 0 is a pointer-to-function; get the type of the function. */
2282 funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
2283 if (! POINTER_TYPE_P (funtype))
2285 funtype = TREE_TYPE (funtype);
2287 /* See if this is a call to a function that can return more than once
2288 or a call to longjmp or malloc. */
2289 flags |= special_function_p (fndecl, flags);
2291 if (flags & ECF_MAY_BE_ALLOCA)
2292 current_function_calls_alloca = 1;
2294 /* If struct_value_rtx is 0, it means pass the address
2295 as if it were an extra parameter. */
2296 if (structure_value_addr && struct_value_rtx == 0)
2298 /* If structure_value_addr is a REG other than
2299 virtual_outgoing_args_rtx, we can use always use it. If it
2300 is not a REG, we must always copy it into a register.
2301 If it is virtual_outgoing_args_rtx, we must copy it to another
2302 register in some cases. */
2303 rtx temp = (GET_CODE (structure_value_addr) != REG
2304 || (ACCUMULATE_OUTGOING_ARGS
2305 && stack_arg_under_construction
2306 && structure_value_addr == virtual_outgoing_args_rtx)
2307 ? copy_addr_to_reg (structure_value_addr)
2308 : structure_value_addr);
2311 = tree_cons (error_mark_node,
2312 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2315 structure_value_addr_parm = 1;
2318 /* Count the arguments and set NUM_ACTUALS. */
2319 for (p = actparms, num_actuals = 0; p; p = TREE_CHAIN (p))
2322 /* Compute number of named args.
2323 Normally, don't include the last named arg if anonymous args follow.
2324 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2325 (If no anonymous args follow, the result of list_length is actually
2326 one too large. This is harmless.)
2328 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2329 zero, this machine will be able to place unnamed args that were
2330 passed in registers into the stack. So treat all args as named.
2331 This allows the insns emitting for a specific argument list to be
2332 independent of the function declaration.
2334 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2335 reliable way to pass unnamed args in registers, so we must force
2336 them into memory. */
2338 if ((STRICT_ARGUMENT_NAMING
2339 || ! PRETEND_OUTGOING_VARARGS_NAMED)
2340 && TYPE_ARG_TYPES (funtype) != 0)
2342 = (list_length (TYPE_ARG_TYPES (funtype))
2343 /* Don't include the last named arg. */
2344 - (STRICT_ARGUMENT_NAMING ? 0 : 1)
2345 /* Count the struct value address, if it is passed as a parm. */
2346 + structure_value_addr_parm);
2348 /* If we know nothing, treat all args as named. */
2349 n_named_args = num_actuals;
2351 /* Start updating where the next arg would go.
2353 On some machines (such as the PA) indirect calls have a different
2354 calling convention than normal calls. The last argument in
2355 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2357 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, (fndecl == 0));
2359 /* Make a vector to hold all the information about each arg. */
2360 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
2361 memset ((char *) args, 0, num_actuals * sizeof (struct arg_data));
2363 /* Build up entries in the ARGS array, compute the size of the
2364 arguments into ARGS_SIZE, etc. */
2365 initialize_argument_information (num_actuals, args, &args_size,
2366 n_named_args, actparms, fndecl,
2367 &args_so_far, reg_parm_stack_space,
2368 &old_stack_level, &old_pending_adj,
2369 &must_preallocate, &flags);
2373 /* If this function requires a variable-sized argument list, don't
2374 try to make a cse'able block for this call. We may be able to
2375 do this eventually, but it is too complicated to keep track of
2376 what insns go in the cse'able block and which don't. */
2378 flags &= ~(ECF_CONST | ECF_PURE);
2379 must_preallocate = 1;
2382 /* Now make final decision about preallocating stack space. */
2383 must_preallocate = finalize_must_preallocate (must_preallocate,
2387 /* If the structure value address will reference the stack pointer, we
2388 must stabilize it. We don't need to do this if we know that we are
2389 not going to adjust the stack pointer in processing this call. */
2391 if (structure_value_addr
2392 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2393 || reg_mentioned_p (virtual_outgoing_args_rtx,
2394 structure_value_addr))
2396 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2397 structure_value_addr = copy_to_reg (structure_value_addr);
2399 /* Tail calls can make things harder to debug, and we're traditionally
2400 pushed these optimizations into -O2. Don't try if we're already
2401 expanding a call, as that means we're an argument. Don't try if
2402 there's cleanups, as we know there's code to follow the call.
2404 If rtx_equal_function_value_matters is false, that means we've
2405 finished with regular parsing. Which means that some of the
2406 machinery we use to generate tail-calls is no longer in place.
2407 This is most often true of sjlj-exceptions, which we couldn't
2408 tail-call to anyway. */
2410 if (currently_expanding_call++ != 0
2411 || !flag_optimize_sibling_calls
2412 || !rtx_equal_function_value_matters
2413 || any_pending_cleanups (1)
2415 try_tail_call = try_tail_recursion = 0;
2417 /* Tail recursion fails, when we are not dealing with recursive calls. */
2418 if (!try_tail_recursion
2419 || TREE_CODE (TREE_OPERAND (exp, 0)) != ADDR_EXPR
2420 || TREE_OPERAND (TREE_OPERAND (exp, 0), 0) != current_function_decl)
2421 try_tail_recursion = 0;
2423 /* Rest of purposes for tail call optimizations to fail. */
2425 #ifdef HAVE_sibcall_epilogue
2426 !HAVE_sibcall_epilogue
2431 /* Doing sibling call optimization needs some work, since
2432 structure_value_addr can be allocated on the stack.
2433 It does not seem worth the effort since few optimizable
2434 sibling calls will return a structure. */
2435 || structure_value_addr != NULL_RTX
2436 /* If the register holding the address is a callee saved
2437 register, then we lose. We have no way to prevent that,
2438 so we only allow calls to named functions. */
2439 /* ??? This could be done by having the insn constraints
2440 use a register class that is all call-clobbered. Any
2441 reload insns generated to fix things up would appear
2442 before the sibcall_epilogue. */
2443 || fndecl == NULL_TREE
2444 || (flags & (ECF_RETURNS_TWICE | ECF_LONGJMP))
2445 || TREE_THIS_VOLATILE (fndecl)
2446 || !FUNCTION_OK_FOR_SIBCALL (fndecl)
2447 /* If this function requires more stack slots than the current
2448 function, we cannot change it into a sibling call. */
2449 || args_size.constant > current_function_args_size
2450 /* If the callee pops its own arguments, then it must pop exactly
2451 the same number of arguments as the current function. */
2452 || RETURN_POPS_ARGS (fndecl, funtype, args_size.constant)
2453 != RETURN_POPS_ARGS (current_function_decl,
2454 TREE_TYPE (current_function_decl),
2455 current_function_args_size))
2458 if (try_tail_call || try_tail_recursion)
2461 actparms = NULL_TREE;
2462 /* Ok, we're going to give the tail call the old college try.
2463 This means we're going to evaluate the function arguments
2464 up to three times. There are two degrees of badness we can
2465 encounter, those that can be unsaved and those that can't.
2466 (See unsafe_for_reeval commentary for details.)
2468 Generate a new argument list. Pass safe arguments through
2469 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2470 For hard badness, evaluate them now and put their resulting
2471 rtx in a temporary VAR_DECL.
2473 initialize_argument_information has ordered the array for the
2474 order to be pushed, and we must remember this when reconstructing
2475 the original argument order. */
2477 if (PUSH_ARGS_REVERSED)
2486 i = num_actuals - 1;
2490 for (; i != end; i += inc)
2492 switch (unsafe_for_reeval (args[i].tree_value))
2497 case 1: /* Mildly unsafe. */
2498 args[i].tree_value = unsave_expr (args[i].tree_value);
2501 case 2: /* Wildly unsafe. */
2503 tree var = build_decl (VAR_DECL, NULL_TREE,
2504 TREE_TYPE (args[i].tree_value));
2506 expand_expr (args[i].tree_value, NULL_RTX,
2507 VOIDmode, EXPAND_NORMAL));
2508 args[i].tree_value = var;
2515 /* We need to build actparms for optimize_tail_recursion. We can
2516 safely trash away TREE_PURPOSE, since it is unused by this
2518 if (try_tail_recursion)
2519 actparms = tree_cons (NULL_TREE, args[i].tree_value, actparms);
2521 /* Expanding one of those dangerous arguments could have added
2522 cleanups, but otherwise give it a whirl. */
2523 if (any_pending_cleanups (1))
2524 try_tail_call = try_tail_recursion = 0;
2527 /* Generate a tail recursion sequence when calling ourselves. */
2529 if (try_tail_recursion)
2531 /* We want to emit any pending stack adjustments before the tail
2532 recursion "call". That way we know any adjustment after the tail
2533 recursion call can be ignored if we indeed use the tail recursion
2535 int save_pending_stack_adjust = pending_stack_adjust;
2536 int save_stack_pointer_delta = stack_pointer_delta;
2538 /* Emit any queued insns now; otherwise they would end up in
2539 only one of the alternates. */
2542 /* Use a new sequence to hold any RTL we generate. We do not even
2543 know if we will use this RTL yet. The final decision can not be
2544 made until after RTL generation for the entire function is
2547 /* If expanding any of the arguments creates cleanups, we can't
2548 do a tailcall. So, we'll need to pop the pending cleanups
2549 list. If, however, all goes well, and there are no cleanups
2550 then the call to expand_start_target_temps will have no
2552 expand_start_target_temps ();
2553 if (optimize_tail_recursion (actparms, get_last_insn ()))
2555 if (any_pending_cleanups (1))
2556 try_tail_call = try_tail_recursion = 0;
2558 tail_recursion_insns = get_insns ();
2560 expand_end_target_temps ();
2563 /* Restore the original pending stack adjustment for the sibling and
2564 normal call cases below. */
2565 pending_stack_adjust = save_pending_stack_adjust;
2566 stack_pointer_delta = save_stack_pointer_delta;
2569 if (profile_arc_flag && (flags & ECF_FORK_OR_EXEC))
2571 /* A fork duplicates the profile information, and an exec discards
2572 it. We can't rely on fork/exec to be paired. So write out the
2573 profile information we have gathered so far, and clear it. */
2574 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2575 is subject to race conditions, just as with multithreaded
2578 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__bb_fork_func"),
2583 /* Ensure current function's preferred stack boundary is at least
2584 what we need. We don't have to increase alignment for recursive
2586 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2587 && fndecl != current_function_decl)
2588 cfun->preferred_stack_boundary = preferred_stack_boundary;
2590 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2592 function_call_count++;
2594 /* We want to make two insn chains; one for a sibling call, the other
2595 for a normal call. We will select one of the two chains after
2596 initial RTL generation is complete. */
2597 for (pass = 0; pass < 2; pass++)
2599 int sibcall_failure = 0;
2600 /* We want to emit any pending stack adjustments before the tail
2601 recursion "call". That way we know any adjustment after the tail
2602 recursion call can be ignored if we indeed use the tail recursion
2604 int save_pending_stack_adjust = 0;
2605 int save_stack_pointer_delta = 0;
2607 rtx before_call, next_arg_reg;
2611 if (! try_tail_call)
2614 /* Emit any queued insns now; otherwise they would end up in
2615 only one of the alternates. */
2618 /* State variables we need to save and restore between
2620 save_pending_stack_adjust = pending_stack_adjust;
2621 save_stack_pointer_delta = stack_pointer_delta;
2624 flags &= ~ECF_SIBCALL;
2626 flags |= ECF_SIBCALL;
2628 /* Other state variables that we must reinitialize each time
2629 through the loop (that are not initialized by the loop itself). */
2633 /* Start a new sequence for the normal call case.
2635 From this point on, if the sibling call fails, we want to set
2636 sibcall_failure instead of continuing the loop. */
2641 /* We know at this point that there are not currently any
2642 pending cleanups. If, however, in the process of evaluating
2643 the arguments we were to create some, we'll need to be
2644 able to get rid of them. */
2645 expand_start_target_temps ();
2648 /* Don't let pending stack adjusts add up to too much.
2649 Also, do all pending adjustments now if there is any chance
2650 this might be a call to alloca or if we are expanding a sibling
2652 if (pending_stack_adjust >= 32
2653 || (pending_stack_adjust > 0 && (flags & ECF_MAY_BE_ALLOCA))
2655 do_pending_stack_adjust ();
2657 /* When calling a const function, we must pop the stack args right away,
2658 so that the pop is deleted or moved with the call. */
2659 if (flags & (ECF_CONST | ECF_PURE))
2662 /* Push the temporary stack slot level so that we can free any
2663 temporaries we make. */
2666 #ifdef FINAL_REG_PARM_STACK_SPACE
2667 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2670 /* Precompute any arguments as needed. */
2672 precompute_arguments (flags, num_actuals, args);
2674 /* Now we are about to start emitting insns that can be deleted
2675 if a libcall is deleted. */
2676 if (flags & (ECF_CONST | ECF_PURE | ECF_MALLOC))
2679 adjusted_args_size = args_size;
2680 /* Compute the actual size of the argument block required. The variable
2681 and constant sizes must be combined, the size may have to be rounded,
2682 and there may be a minimum required size. When generating a sibcall
2683 pattern, do not round up, since we'll be re-using whatever space our
2685 unadjusted_args_size
2686 = compute_argument_block_size (reg_parm_stack_space,
2687 &adjusted_args_size,
2689 : preferred_stack_boundary));
2691 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2693 /* The argument block when performing a sibling call is the
2694 incoming argument block. */
2697 argblock = virtual_incoming_args_rtx;
2698 stored_args_map = sbitmap_alloc (args_size.constant);
2699 sbitmap_zero (stored_args_map);
2702 /* If we have no actual push instructions, or shouldn't use them,
2703 make space for all args right now. */
2704 else if (adjusted_args_size.var != 0)
2706 if (old_stack_level == 0)
2708 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2709 old_pending_adj = pending_stack_adjust;
2710 pending_stack_adjust = 0;
2711 /* stack_arg_under_construction says whether a stack arg is
2712 being constructed at the old stack level. Pushing the stack
2713 gets a clean outgoing argument block. */
2714 old_stack_arg_under_construction = stack_arg_under_construction;
2715 stack_arg_under_construction = 0;
2717 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2721 /* Note that we must go through the motions of allocating an argument
2722 block even if the size is zero because we may be storing args
2723 in the area reserved for register arguments, which may be part of
2726 int needed = adjusted_args_size.constant;
2728 /* Store the maximum argument space used. It will be pushed by
2729 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2732 if (needed > current_function_outgoing_args_size)
2733 current_function_outgoing_args_size = needed;
2735 if (must_preallocate)
2737 if (ACCUMULATE_OUTGOING_ARGS)
2739 /* Since the stack pointer will never be pushed, it is
2740 possible for the evaluation of a parm to clobber
2741 something we have already written to the stack.
2742 Since most function calls on RISC machines do not use
2743 the stack, this is uncommon, but must work correctly.
2745 Therefore, we save any area of the stack that was already
2746 written and that we are using. Here we set up to do this
2747 by making a new stack usage map from the old one. The
2748 actual save will be done by store_one_arg.
2750 Another approach might be to try to reorder the argument
2751 evaluations to avoid this conflicting stack usage. */
2753 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2754 /* Since we will be writing into the entire argument area,
2755 the map must be allocated for its entire size, not just
2756 the part that is the responsibility of the caller. */
2757 needed += reg_parm_stack_space;
2760 #ifdef ARGS_GROW_DOWNWARD
2761 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2764 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2768 = (char *) alloca (highest_outgoing_arg_in_use);
2770 if (initial_highest_arg_in_use)
2771 memcpy (stack_usage_map, initial_stack_usage_map,
2772 initial_highest_arg_in_use);
2774 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2775 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2776 (highest_outgoing_arg_in_use
2777 - initial_highest_arg_in_use));
2780 /* The address of the outgoing argument list must not be
2781 copied to a register here, because argblock would be left
2782 pointing to the wrong place after the call to
2783 allocate_dynamic_stack_space below. */
2785 argblock = virtual_outgoing_args_rtx;
2789 if (inhibit_defer_pop == 0)
2791 /* Try to reuse some or all of the pending_stack_adjust
2792 to get this space. */
2794 = (combine_pending_stack_adjustment_and_call
2795 (unadjusted_args_size,
2796 &adjusted_args_size,
2797 preferred_unit_stack_boundary));
2799 /* combine_pending_stack_adjustment_and_call computes
2800 an adjustment before the arguments are allocated.
2801 Account for them and see whether or not the stack
2802 needs to go up or down. */
2803 needed = unadjusted_args_size - needed;
2807 /* We're releasing stack space. */
2808 /* ??? We can avoid any adjustment at all if we're
2809 already aligned. FIXME. */
2810 pending_stack_adjust = -needed;
2811 do_pending_stack_adjust ();
2815 /* We need to allocate space. We'll do that in
2816 push_block below. */
2817 pending_stack_adjust = 0;
2820 /* Special case this because overhead of `push_block' in
2821 this case is non-trivial. */
2823 argblock = virtual_outgoing_args_rtx;
2825 argblock = push_block (GEN_INT (needed), 0, 0);
2827 /* We only really need to call `copy_to_reg' in the case
2828 where push insns are going to be used to pass ARGBLOCK
2829 to a function call in ARGS. In that case, the stack
2830 pointer changes value from the allocation point to the
2831 call point, and hence the value of
2832 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2833 as well always do it. */
2834 argblock = copy_to_reg (argblock);
2836 /* The save/restore code in store_one_arg handles all
2837 cases except one: a constructor call (including a C
2838 function returning a BLKmode struct) to initialize
2840 if (stack_arg_under_construction)
2842 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2843 rtx push_size = GEN_INT (reg_parm_stack_space
2844 + adjusted_args_size.constant);
2846 rtx push_size = GEN_INT (adjusted_args_size.constant);
2848 if (old_stack_level == 0)
2850 emit_stack_save (SAVE_BLOCK, &old_stack_level,
2852 old_pending_adj = pending_stack_adjust;
2853 pending_stack_adjust = 0;
2854 /* stack_arg_under_construction says whether a stack
2855 arg is being constructed at the old stack level.
2856 Pushing the stack gets a clean outgoing argument
2858 old_stack_arg_under_construction
2859 = stack_arg_under_construction;
2860 stack_arg_under_construction = 0;
2861 /* Make a new map for the new argument list. */
2862 stack_usage_map = (char *)
2863 alloca (highest_outgoing_arg_in_use);
2864 memset (stack_usage_map, 0, highest_outgoing_arg_in_use);
2865 highest_outgoing_arg_in_use = 0;
2867 allocate_dynamic_stack_space (push_size, NULL_RTX,
2870 /* If argument evaluation might modify the stack pointer,
2871 copy the address of the argument list to a register. */
2872 for (i = 0; i < num_actuals; i++)
2873 if (args[i].pass_on_stack)
2875 argblock = copy_addr_to_reg (argblock);
2882 compute_argument_addresses (args, argblock, num_actuals);
2884 /* If we push args individually in reverse order, perform stack alignment
2885 before the first push (the last arg). */
2886 if (PUSH_ARGS_REVERSED && argblock == 0
2887 && adjusted_args_size.constant != unadjusted_args_size)
2889 /* When the stack adjustment is pending, we get better code
2890 by combining the adjustments. */
2891 if (pending_stack_adjust
2892 && ! (flags & (ECF_CONST | ECF_PURE))
2893 && ! inhibit_defer_pop)
2895 pending_stack_adjust
2896 = (combine_pending_stack_adjustment_and_call
2897 (unadjusted_args_size,
2898 &adjusted_args_size,
2899 preferred_unit_stack_boundary));
2900 do_pending_stack_adjust ();
2902 else if (argblock == 0)
2903 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2904 - unadjusted_args_size));
2906 /* Now that the stack is properly aligned, pops can't safely
2907 be deferred during the evaluation of the arguments. */
2910 funexp = rtx_for_function_call (fndecl, exp);
2912 /* Figure out the register where the value, if any, will come back. */
2914 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2915 && ! structure_value_addr)
2917 if (pcc_struct_value)
2918 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2919 fndecl, (pass == 0));
2921 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
2924 /* Precompute all register parameters. It isn't safe to compute anything
2925 once we have started filling any specific hard regs. */
2926 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2928 #ifdef REG_PARM_STACK_SPACE
2929 /* Save the fixed argument area if it's part of the caller's frame and
2930 is clobbered by argument setup for this call. */
2931 if (ACCUMULATE_OUTGOING_ARGS && pass)
2932 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2933 &low_to_save, &high_to_save);
2936 /* Now store (and compute if necessary) all non-register parms.
2937 These come before register parms, since they can require block-moves,
2938 which could clobber the registers used for register parms.
2939 Parms which have partial registers are not stored here,
2940 but we do preallocate space here if they want that. */
2942 for (i = 0; i < num_actuals; i++)
2943 if (args[i].reg == 0 || args[i].pass_on_stack)
2945 rtx before_arg = get_last_insn ();
2947 if (store_one_arg (&args[i], argblock, flags,
2948 adjusted_args_size.var != 0,
2949 reg_parm_stack_space)
2951 && check_sibcall_argument_overlap (before_arg,
2953 sibcall_failure = 1;
2956 /* If we have a parm that is passed in registers but not in memory
2957 and whose alignment does not permit a direct copy into registers,
2958 make a group of pseudos that correspond to each register that we
2960 if (STRICT_ALIGNMENT)
2961 store_unaligned_arguments_into_pseudos (args, num_actuals);
2963 /* Now store any partially-in-registers parm.
2964 This is the last place a block-move can happen. */
2966 for (i = 0; i < num_actuals; i++)
2967 if (args[i].partial != 0 && ! args[i].pass_on_stack)
2969 rtx before_arg = get_last_insn ();
2971 if (store_one_arg (&args[i], argblock, flags,
2972 adjusted_args_size.var != 0,
2973 reg_parm_stack_space)
2975 && check_sibcall_argument_overlap (before_arg,
2977 sibcall_failure = 1;
2980 /* If we pushed args in forward order, perform stack alignment
2981 after pushing the last arg. */
2982 if (!PUSH_ARGS_REVERSED && argblock == 0)
2983 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2984 - unadjusted_args_size));
2986 /* If register arguments require space on the stack and stack space
2987 was not preallocated, allocate stack space here for arguments
2988 passed in registers. */
2989 #ifdef OUTGOING_REG_PARM_STACK_SPACE
2990 if (!ACCUMULATE_OUTGOING_ARGS
2991 && must_preallocate == 0 && reg_parm_stack_space > 0)
2992 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
2995 /* Pass the function the address in which to return a
2997 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
2999 emit_move_insn (struct_value_rtx,
3001 force_operand (structure_value_addr,
3004 if (GET_CODE (struct_value_rtx) == REG)
3005 use_reg (&call_fusage, struct_value_rtx);
3008 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
3009 reg_parm_seen, pass == 0);
3011 load_register_parameters (args, num_actuals, &call_fusage, flags);
3013 /* Perform postincrements before actually calling the function. */
3016 /* Save a pointer to the last insn before the call, so that we can
3017 later safely search backwards to find the CALL_INSN. */
3018 before_call = get_last_insn ();
3020 /* Set up next argument register. For sibling calls on machines
3021 with register windows this should be the incoming register. */
3022 #ifdef FUNCTION_INCOMING_ARG
3024 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
3028 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
3031 /* All arguments and registers used for the call must be set up by
3034 /* Stack must be properly aligned now. */
3035 if (pass && stack_pointer_delta % preferred_unit_stack_boundary)
3038 /* Generate the actual call instruction. */
3039 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
3040 adjusted_args_size.constant, struct_value_size,
3041 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3044 /* Verify that we've deallocated all the stack we used. */
3046 && old_stack_allocated != stack_pointer_delta - pending_stack_adjust)
3049 /* If call is cse'able, make appropriate pair of reg-notes around it.
3050 Test valreg so we don't crash; may safely ignore `const'
3051 if return type is void. Disable for PARALLEL return values, because
3052 we have no way to move such values into a pseudo register. */
3054 && (flags & (ECF_CONST | ECF_PURE))
3055 && valreg != 0 && GET_CODE (valreg) != PARALLEL)
3058 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3061 /* Mark the return value as a pointer if needed. */
3062 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3063 mark_reg_pointer (temp, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
3065 /* Construct an "equal form" for the value which mentions all the
3066 arguments in order as well as the function name. */
3067 for (i = 0; i < num_actuals; i++)
3068 note = gen_rtx_EXPR_LIST (VOIDmode, args[i].initial_value, note);
3069 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
3071 insns = get_insns ();
3074 if (flags & ECF_PURE)
3075 note = gen_rtx_EXPR_LIST (VOIDmode,
3076 gen_rtx_USE (VOIDmode,
3077 gen_rtx_MEM (BLKmode,
3078 gen_rtx_SCRATCH (VOIDmode))), note);
3080 emit_libcall_block (insns, temp, valreg, note);
3084 else if (flags & (ECF_CONST | ECF_PURE))
3086 /* Otherwise, just write out the sequence without a note. */
3087 rtx insns = get_insns ();
3092 else if (flags & ECF_MALLOC)
3094 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3097 /* The return value from a malloc-like function is a pointer. */
3098 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3099 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3101 emit_move_insn (temp, valreg);
3103 /* The return value from a malloc-like function can not alias
3105 last = get_last_insn ();
3107 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
3109 /* Write out the sequence. */
3110 insns = get_insns ();
3116 /* For calls to `setjmp', etc., inform flow.c it should complain
3117 if nonvolatile values are live. For functions that cannot return,
3118 inform flow that control does not fall through. */
3120 if ((flags & (ECF_NORETURN | ECF_LONGJMP)) || pass == 0)
3122 /* The barrier must be emitted
3123 immediately after the CALL_INSN. Some ports emit more
3124 than just a CALL_INSN above, so we must search for it here. */
3126 rtx last = get_last_insn ();
3127 while (GET_CODE (last) != CALL_INSN)
3129 last = PREV_INSN (last);
3130 /* There was no CALL_INSN? */
3131 if (last == before_call)
3135 emit_barrier_after (last);
3138 if (flags & ECF_LONGJMP)
3139 current_function_calls_longjmp = 1;
3141 /* If this function is returning into a memory location marked as
3142 readonly, it means it is initializing that location. But we normally
3143 treat functions as not clobbering such locations, so we need to
3144 specify that this one does. */
3145 if (target != 0 && GET_CODE (target) == MEM
3146 && structure_value_addr != 0 && RTX_UNCHANGING_P (target))
3147 emit_insn (gen_rtx_CLOBBER (VOIDmode, target));
3149 /* If value type not void, return an rtx for the value. */
3151 /* If there are cleanups to be called, don't use a hard reg as target.
3152 We need to double check this and see if it matters anymore. */
3153 if (any_pending_cleanups (1))
3155 if (target && REG_P (target)
3156 && REGNO (target) < FIRST_PSEUDO_REGISTER)
3158 sibcall_failure = 1;
3161 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
3164 target = const0_rtx;
3166 else if (structure_value_addr)
3168 if (target == 0 || GET_CODE (target) != MEM)
3171 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3172 memory_address (TYPE_MODE (TREE_TYPE (exp)),
3173 structure_value_addr));
3174 set_mem_attributes (target, exp, 1);
3177 else if (pcc_struct_value)
3179 /* This is the special C++ case where we need to
3180 know what the true target was. We take care to
3181 never use this value more than once in one expression. */
3182 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3183 copy_to_reg (valreg));
3184 set_mem_attributes (target, exp, 1);
3186 /* Handle calls that return values in multiple non-contiguous locations.
3187 The Irix 6 ABI has examples of this. */
3188 else if (GET_CODE (valreg) == PARALLEL)
3192 /* This will only be assigned once, so it can be readonly. */
3193 tree nt = build_qualified_type (TREE_TYPE (exp),
3194 (TYPE_QUALS (TREE_TYPE (exp))
3195 | TYPE_QUAL_CONST));
3197 target = assign_temp (nt, 0, 1, 1);
3198 preserve_temp_slots (target);
3201 if (! rtx_equal_p (target, valreg))
3202 emit_group_store (target, valreg,
3203 int_size_in_bytes (TREE_TYPE (exp)));
3205 /* We can not support sibling calls for this case. */
3206 sibcall_failure = 1;
3209 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
3210 && GET_MODE (target) == GET_MODE (valreg))
3212 /* TARGET and VALREG cannot be equal at this point because the
3213 latter would not have REG_FUNCTION_VALUE_P true, while the
3214 former would if it were referring to the same register.
3216 If they refer to the same register, this move will be a no-op,
3217 except when function inlining is being done. */
3218 emit_move_insn (target, valreg);
3220 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3222 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3224 /* We can not support sibling calls for this case. */
3225 sibcall_failure = 1;
3228 target = copy_to_reg (valreg);
3230 #ifdef PROMOTE_FUNCTION_RETURN
3231 /* If we promoted this return value, make the proper SUBREG. TARGET
3232 might be const0_rtx here, so be careful. */
3233 if (GET_CODE (target) == REG
3234 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3235 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3237 tree type = TREE_TYPE (exp);
3238 int unsignedp = TREE_UNSIGNED (type);
3241 /* If we don't promote as expected, something is wrong. */
3242 if (GET_MODE (target)
3243 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
3246 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3247 && GET_MODE_SIZE (GET_MODE (target))
3248 > GET_MODE_SIZE (TYPE_MODE (type)))
3250 offset = GET_MODE_SIZE (GET_MODE (target))
3251 - GET_MODE_SIZE (TYPE_MODE (type));
3252 if (! BYTES_BIG_ENDIAN)
3253 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3254 else if (! WORDS_BIG_ENDIAN)
3255 offset %= UNITS_PER_WORD;
3257 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3258 SUBREG_PROMOTED_VAR_P (target) = 1;
3259 SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
3263 /* If size of args is variable or this was a constructor call for a stack
3264 argument, restore saved stack-pointer value. */
3266 if (old_stack_level && ! (flags & ECF_SP_DEPRESSED))
3268 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3269 pending_stack_adjust = old_pending_adj;
3270 stack_arg_under_construction = old_stack_arg_under_construction;
3271 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3272 stack_usage_map = initial_stack_usage_map;
3273 sibcall_failure = 1;
3275 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3277 #ifdef REG_PARM_STACK_SPACE
3280 restore_fixed_argument_area (save_area, argblock,
3281 high_to_save, low_to_save);
3285 /* If we saved any argument areas, restore them. */
3286 for (i = 0; i < num_actuals; i++)
3287 if (args[i].save_area)
3289 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3291 = gen_rtx_MEM (save_mode,
3292 memory_address (save_mode,
3293 XEXP (args[i].stack_slot, 0)));
3295 if (save_mode != BLKmode)
3296 emit_move_insn (stack_area, args[i].save_area);
3298 emit_block_move (stack_area,
3299 validize_mem (args[i].save_area),
3300 GEN_INT (args[i].size.constant));
3303 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3304 stack_usage_map = initial_stack_usage_map;
3307 /* If this was alloca, record the new stack level for nonlocal gotos.
3308 Check for the handler slots since we might not have a save area
3309 for non-local gotos. */
3311 if ((flags & ECF_MAY_BE_ALLOCA) && nonlocal_goto_handler_slots != 0)
3312 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3316 /* Free up storage we no longer need. */
3317 for (i = 0; i < num_actuals; ++i)
3318 if (args[i].aligned_regs)
3319 free (args[i].aligned_regs);
3323 /* Undo the fake expand_start_target_temps we did earlier. If
3324 there had been any cleanups created, we've already set
3326 expand_end_target_temps ();
3329 insns = get_insns ();
3334 tail_call_insns = insns;
3336 /* Restore the pending stack adjustment now that we have
3337 finished generating the sibling call sequence. */
3339 pending_stack_adjust = save_pending_stack_adjust;
3340 stack_pointer_delta = save_stack_pointer_delta;
3342 /* Prepare arg structure for next iteration. */
3343 for (i = 0; i < num_actuals; i++)
3346 args[i].aligned_regs = 0;
3350 sbitmap_free (stored_args_map);
3353 normal_call_insns = insns;
3355 /* If something prevents making this a sibling call,
3356 zero out the sequence. */
3357 if (sibcall_failure)
3358 tail_call_insns = NULL_RTX;
3361 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3362 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3363 can happen if the arguments to this function call an inline
3364 function who's expansion contains another CALL_PLACEHOLDER.
3366 If there are any C_Ps in any of these sequences, replace them
3367 with their normal call. */
3369 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3370 if (GET_CODE (insn) == CALL_INSN
3371 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3372 replace_call_placeholder (insn, sibcall_use_normal);
3374 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
3375 if (GET_CODE (insn) == CALL_INSN
3376 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3377 replace_call_placeholder (insn, sibcall_use_normal);
3379 for (insn = tail_recursion_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 /* If this was a potential tail recursion site, then emit a
3385 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3386 One of them will be selected later. */
3387 if (tail_recursion_insns || tail_call_insns)
3389 /* The tail recursion label must be kept around. We could expose
3390 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3391 and makes determining true tail recursion sites difficult.
3393 So we set LABEL_PRESERVE_P here, then clear it when we select
3394 one of the call sequences after rtl generation is complete. */
3395 if (tail_recursion_insns)
3396 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3397 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3399 tail_recursion_insns,
3400 tail_recursion_label));
3403 emit_insns (normal_call_insns);
3405 currently_expanding_call--;
3407 /* If this function returns with the stack pointer depressed, ensure
3408 this block saves and restores the stack pointer, show it was
3409 changed, and adjust for any outgoing arg space. */
3410 if (flags & ECF_SP_DEPRESSED)
3412 clear_pending_stack_adjust ();
3413 emit_insn (gen_rtx (CLOBBER, VOIDmode, stack_pointer_rtx));
3414 emit_move_insn (virtual_stack_dynamic_rtx, stack_pointer_rtx);
3415 save_stack_pointer ();
3421 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3422 The RETVAL parameter specifies whether return value needs to be saved, other
3423 parameters are documented in the emit_library_call function below. */
3426 emit_library_call_value_1 (retval, orgfun, value, fn_type, outmode, nargs, p)
3430 enum libcall_type fn_type;
3431 enum machine_mode outmode;
3435 /* Total size in bytes of all the stack-parms scanned so far. */
3436 struct args_size args_size;
3437 /* Size of arguments before any adjustments (such as rounding). */
3438 struct args_size original_args_size;
3443 struct args_size alignment_pad;
3445 CUMULATIVE_ARGS args_so_far;
3449 enum machine_mode mode;
3452 struct args_size offset;
3453 struct args_size size;
3457 int old_inhibit_defer_pop = inhibit_defer_pop;
3458 rtx call_fusage = 0;
3461 int pcc_struct_value = 0;
3462 int struct_value_size = 0;
3464 int reg_parm_stack_space = 0;
3468 #ifdef REG_PARM_STACK_SPACE
3469 /* Define the boundary of the register parm stack space that needs to be
3471 int low_to_save = -1, high_to_save = 0;
3472 rtx save_area = 0; /* Place that it is saved. */
3475 /* Size of the stack reserved for parameter registers. */
3476 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3477 char *initial_stack_usage_map = stack_usage_map;
3479 #ifdef REG_PARM_STACK_SPACE
3480 #ifdef MAYBE_REG_PARM_STACK_SPACE
3481 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3483 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3487 /* By default, library functions can not throw. */
3488 flags = ECF_NOTHROW;
3495 /* Nothing to do here. */
3497 case LCT_CONST_MAKE_BLOCK:
3500 case LCT_PURE_MAKE_BLOCK:
3504 flags |= ECF_NORETURN;
3507 flags = ECF_NORETURN;
3509 case LCT_ALWAYS_RETURN:
3510 flags = ECF_ALWAYS_RETURN;
3512 case LCT_RETURNS_TWICE:
3513 flags = ECF_RETURNS_TWICE;
3518 /* Ensure current function's preferred stack boundary is at least
3520 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3521 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3523 /* If this kind of value comes back in memory,
3524 decide where in memory it should come back. */
3525 if (outmode != VOIDmode && aggregate_value_p (type_for_mode (outmode, 0)))
3527 #ifdef PCC_STATIC_STRUCT_RETURN
3529 = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
3531 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3532 pcc_struct_value = 1;
3534 value = gen_reg_rtx (outmode);
3535 #else /* not PCC_STATIC_STRUCT_RETURN */
3536 struct_value_size = GET_MODE_SIZE (outmode);
3537 if (value != 0 && GET_CODE (value) == MEM)
3540 mem_value = assign_temp (type_for_mode (outmode, 0), 0, 1, 1);
3543 /* This call returns a big structure. */
3544 flags &= ~(ECF_CONST | ECF_PURE);
3547 /* ??? Unfinished: must pass the memory address as an argument. */
3549 /* Copy all the libcall-arguments out of the varargs data
3550 and into a vector ARGVEC.
3552 Compute how to pass each argument. We only support a very small subset
3553 of the full argument passing conventions to limit complexity here since
3554 library functions shouldn't have many args. */
3556 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
3557 memset ((char *) argvec, 0, (nargs + 1) * sizeof (struct arg));
3559 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3560 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far, outmode, fun);
3562 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
3565 args_size.constant = 0;
3570 /* Now we are about to start emitting insns that can be deleted
3571 if a libcall is deleted. */
3572 if (flags & (ECF_CONST | ECF_PURE))
3577 /* If there's a structure value address to be passed,
3578 either pass it in the special place, or pass it as an extra argument. */
3579 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
3581 rtx addr = XEXP (mem_value, 0);
3584 /* Make sure it is a reasonable operand for a move or push insn. */
3585 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3586 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3587 addr = force_operand (addr, NULL_RTX);
3589 argvec[count].value = addr;
3590 argvec[count].mode = Pmode;
3591 argvec[count].partial = 0;
3593 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3594 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3595 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3599 locate_and_pad_parm (Pmode, NULL_TREE,
3600 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3603 argvec[count].reg != 0,
3605 NULL_TREE, &args_size, &argvec[count].offset,
3606 &argvec[count].size, &alignment_pad);
3608 if (argvec[count].reg == 0 || argvec[count].partial != 0
3609 || reg_parm_stack_space > 0)
3610 args_size.constant += argvec[count].size.constant;
3612 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3617 for (; count < nargs; count++)
3619 rtx val = va_arg (p, rtx);
3620 enum machine_mode mode = va_arg (p, enum machine_mode);
3622 /* We cannot convert the arg value to the mode the library wants here;
3623 must do it earlier where we know the signedness of the arg. */
3625 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3628 /* On some machines, there's no way to pass a float to a library fcn.
3629 Pass it as a double instead. */
3630 #ifdef LIBGCC_NEEDS_DOUBLE
3631 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
3632 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
3635 /* There's no need to call protect_from_queue, because
3636 either emit_move_insn or emit_push_insn will do that. */
3638 /* Make sure it is a reasonable operand for a move or push insn. */
3639 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3640 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3641 val = force_operand (val, NULL_RTX);
3643 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3644 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3648 #ifdef FUNCTION_ARG_CALLEE_COPIES
3649 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far, mode,
3654 if (GET_MODE (val) == MEM && ! must_copy)
3658 slot = assign_temp (type_for_mode (mode, 0), 0, 1, 1);
3659 emit_move_insn (slot, val);
3663 tree type = type_for_mode (mode, 0);
3665 slot = gen_rtx_MEM (mode,
3666 expand_expr (build1 (ADDR_EXPR,
3669 make_tree (type, val)),
3670 NULL_RTX, VOIDmode, 0));
3673 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3674 gen_rtx_USE (VOIDmode, slot),
3677 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3678 gen_rtx_CLOBBER (VOIDmode,
3683 val = force_operand (XEXP (slot, 0), NULL_RTX);
3687 argvec[count].value = val;
3688 argvec[count].mode = mode;
3690 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3692 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3693 argvec[count].partial
3694 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3696 argvec[count].partial = 0;
3699 locate_and_pad_parm (mode, NULL_TREE,
3700 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3703 argvec[count].reg != 0,
3705 NULL_TREE, &args_size, &argvec[count].offset,
3706 &argvec[count].size, &alignment_pad);
3708 if (argvec[count].size.var)
3711 if (reg_parm_stack_space == 0 && argvec[count].partial)
3712 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
3714 if (argvec[count].reg == 0 || argvec[count].partial != 0
3715 || reg_parm_stack_space > 0)
3716 args_size.constant += argvec[count].size.constant;
3718 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3721 #ifdef FINAL_REG_PARM_STACK_SPACE
3722 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3725 /* If this machine requires an external definition for library
3726 functions, write one out. */
3727 assemble_external_libcall (fun);
3729 original_args_size = args_size;
3730 args_size.constant = (((args_size.constant
3731 + stack_pointer_delta
3735 - stack_pointer_delta);
3737 args_size.constant = MAX (args_size.constant,
3738 reg_parm_stack_space);
3740 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3741 args_size.constant -= reg_parm_stack_space;
3744 if (args_size.constant > current_function_outgoing_args_size)
3745 current_function_outgoing_args_size = args_size.constant;
3747 if (ACCUMULATE_OUTGOING_ARGS)
3749 /* Since the stack pointer will never be pushed, it is possible for
3750 the evaluation of a parm to clobber something we have already
3751 written to the stack. Since most function calls on RISC machines
3752 do not use the stack, this is uncommon, but must work correctly.
3754 Therefore, we save any area of the stack that was already written
3755 and that we are using. Here we set up to do this by making a new
3756 stack usage map from the old one.
3758 Another approach might be to try to reorder the argument
3759 evaluations to avoid this conflicting stack usage. */
3761 needed = args_size.constant;
3763 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3764 /* Since we will be writing into the entire argument area, the
3765 map must be allocated for its entire size, not just the part that
3766 is the responsibility of the caller. */
3767 needed += reg_parm_stack_space;
3770 #ifdef ARGS_GROW_DOWNWARD
3771 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3774 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3777 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
3779 if (initial_highest_arg_in_use)
3780 memcpy (stack_usage_map, initial_stack_usage_map,
3781 initial_highest_arg_in_use);
3783 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3784 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3785 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3788 /* We must be careful to use virtual regs before they're instantiated,
3789 and real regs afterwards. Loop optimization, for example, can create
3790 new libcalls after we've instantiated the virtual regs, and if we
3791 use virtuals anyway, they won't match the rtl patterns. */
3793 if (virtuals_instantiated)
3794 argblock = plus_constant (stack_pointer_rtx, STACK_POINTER_OFFSET);
3796 argblock = virtual_outgoing_args_rtx;
3801 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3804 /* If we push args individually in reverse order, perform stack alignment
3805 before the first push (the last arg). */
3806 if (argblock == 0 && PUSH_ARGS_REVERSED)
3807 anti_adjust_stack (GEN_INT (args_size.constant
3808 - original_args_size.constant));
3810 if (PUSH_ARGS_REVERSED)
3821 #ifdef REG_PARM_STACK_SPACE
3822 if (ACCUMULATE_OUTGOING_ARGS)
3824 /* The argument list is the property of the called routine and it
3825 may clobber it. If the fixed area has been used for previous
3826 parameters, we must save and restore it.
3828 Here we compute the boundary of the that needs to be saved, if any. */
3830 #ifdef ARGS_GROW_DOWNWARD
3831 for (count = 0; count < reg_parm_stack_space + 1; count++)
3833 for (count = 0; count < reg_parm_stack_space; count++)
3836 if (count >= highest_outgoing_arg_in_use
3837 || stack_usage_map[count] == 0)
3840 if (low_to_save == -1)
3841 low_to_save = count;
3843 high_to_save = count;
3846 if (low_to_save >= 0)
3848 int num_to_save = high_to_save - low_to_save + 1;
3849 enum machine_mode save_mode
3850 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
3853 /* If we don't have the required alignment, must do this in BLKmode. */
3854 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
3855 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
3856 save_mode = BLKmode;
3858 #ifdef ARGS_GROW_DOWNWARD
3859 stack_area = gen_rtx_MEM (save_mode,
3860 memory_address (save_mode,
3861 plus_constant (argblock,
3864 stack_area = gen_rtx_MEM (save_mode,
3865 memory_address (save_mode,
3866 plus_constant (argblock,
3869 if (save_mode == BLKmode)
3871 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
3872 set_mem_align (save_area, PARM_BOUNDARY);
3873 emit_block_move (validize_mem (save_area), stack_area,
3874 GEN_INT (num_to_save));
3878 save_area = gen_reg_rtx (save_mode);
3879 emit_move_insn (save_area, stack_area);
3885 /* Push the args that need to be pushed. */
3887 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3888 are to be pushed. */
3889 for (count = 0; count < nargs; count++, argnum += inc)
3891 enum machine_mode mode = argvec[argnum].mode;
3892 rtx val = argvec[argnum].value;
3893 rtx reg = argvec[argnum].reg;
3894 int partial = argvec[argnum].partial;
3895 int lower_bound = 0, upper_bound = 0, i;
3897 if (! (reg != 0 && partial == 0))
3899 if (ACCUMULATE_OUTGOING_ARGS)
3901 /* If this is being stored into a pre-allocated, fixed-size,
3902 stack area, save any previous data at that location. */
3904 #ifdef ARGS_GROW_DOWNWARD
3905 /* stack_slot is negative, but we want to index stack_usage_map
3906 with positive values. */
3907 upper_bound = -argvec[argnum].offset.constant + 1;
3908 lower_bound = upper_bound - argvec[argnum].size.constant;
3910 lower_bound = argvec[argnum].offset.constant;
3911 upper_bound = lower_bound + argvec[argnum].size.constant;
3914 for (i = lower_bound; i < upper_bound; i++)
3915 if (stack_usage_map[i]
3916 /* Don't store things in the fixed argument area at this
3917 point; it has already been saved. */
3918 && i > reg_parm_stack_space)
3921 if (i != upper_bound)
3923 /* We need to make a save area. See what mode we can make
3925 enum machine_mode save_mode
3926 = mode_for_size (argvec[argnum].size.constant
3934 plus_constant (argblock,
3935 argvec[argnum].offset.constant)));
3936 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3938 emit_move_insn (argvec[argnum].save_area, stack_area);
3942 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
3943 argblock, GEN_INT (argvec[argnum].offset.constant),
3944 reg_parm_stack_space, ARGS_SIZE_RTX (alignment_pad));
3946 /* Now mark the segment we just used. */
3947 if (ACCUMULATE_OUTGOING_ARGS)
3948 for (i = lower_bound; i < upper_bound; i++)
3949 stack_usage_map[i] = 1;
3955 /* If we pushed args in forward order, perform stack alignment
3956 after pushing the last arg. */
3957 if (argblock == 0 && !PUSH_ARGS_REVERSED)
3958 anti_adjust_stack (GEN_INT (args_size.constant
3959 - original_args_size.constant));
3961 if (PUSH_ARGS_REVERSED)
3966 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0, 0);
3968 /* Now load any reg parms into their regs. */
3970 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3971 are to be pushed. */
3972 for (count = 0; count < nargs; count++, argnum += inc)
3974 rtx val = argvec[argnum].value;
3975 rtx reg = argvec[argnum].reg;
3976 int partial = argvec[argnum].partial;
3978 /* Handle calls that pass values in multiple non-contiguous
3979 locations. The PA64 has examples of this for library calls. */
3980 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3981 emit_group_load (reg, val, GET_MODE_SIZE (GET_MODE (val)));
3982 else if (reg != 0 && partial == 0)
3983 emit_move_insn (reg, val);
3988 /* Any regs containing parms remain in use through the call. */
3989 for (count = 0; count < nargs; count++)
3991 rtx reg = argvec[count].reg;
3992 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3993 use_group_regs (&call_fusage, reg);
3995 use_reg (&call_fusage, reg);
3998 /* Pass the function the address in which to return a structure value. */
3999 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
4001 emit_move_insn (struct_value_rtx,
4003 force_operand (XEXP (mem_value, 0),
4005 if (GET_CODE (struct_value_rtx) == REG)
4006 use_reg (&call_fusage, struct_value_rtx);
4009 /* Don't allow popping to be deferred, since then
4010 cse'ing of library calls could delete a call and leave the pop. */
4012 valreg = (mem_value == 0 && outmode != VOIDmode
4013 ? hard_libcall_value (outmode) : NULL_RTX);
4015 /* Stack must be properly aligned now. */
4016 if (stack_pointer_delta & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1))
4019 before_call = get_last_insn ();
4021 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4022 will set inhibit_defer_pop to that value. */
4023 /* The return type is needed to decide how many bytes the function pops.
4024 Signedness plays no role in that, so for simplicity, we pretend it's
4025 always signed. We also assume that the list of arguments passed has
4026 no impact, so we pretend it is unknown. */
4029 get_identifier (XSTR (orgfun, 0)),
4030 build_function_type (outmode == VOIDmode ? void_type_node
4031 : type_for_mode (outmode, 0), NULL_TREE),
4032 original_args_size.constant, args_size.constant,
4034 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
4036 old_inhibit_defer_pop + 1, call_fusage, flags);
4038 /* For calls to `setjmp', etc., inform flow.c it should complain
4039 if nonvolatile values are live. For functions that cannot return,
4040 inform flow that control does not fall through. */
4042 if (flags & (ECF_NORETURN | ECF_LONGJMP))
4044 /* The barrier note must be emitted
4045 immediately after the CALL_INSN. Some ports emit more than
4046 just a CALL_INSN above, so we must search for it here. */
4048 rtx last = get_last_insn ();
4049 while (GET_CODE (last) != CALL_INSN)
4051 last = PREV_INSN (last);
4052 /* There was no CALL_INSN? */
4053 if (last == before_call)
4057 emit_barrier_after (last);
4060 /* Now restore inhibit_defer_pop to its actual original value. */
4063 /* If call is cse'able, make appropriate pair of reg-notes around it.
4064 Test valreg so we don't crash; may safely ignore `const'
4065 if return type is void. Disable for PARALLEL return values, because
4066 we have no way to move such values into a pseudo register. */
4067 if ((flags & (ECF_CONST | ECF_PURE))
4068 && valreg != 0 && GET_CODE (valreg) != PARALLEL)
4071 rtx temp = gen_reg_rtx (GET_MODE (valreg));
4075 /* Construct an "equal form" for the value which mentions all the
4076 arguments in order as well as the function name. */
4077 for (i = 0; i < nargs; i++)
4078 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
4079 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
4081 insns = get_insns ();
4084 if (flags & ECF_PURE)
4085 note = gen_rtx_EXPR_LIST (VOIDmode,
4086 gen_rtx_USE (VOIDmode,
4087 gen_rtx_MEM (BLKmode,
4088 gen_rtx_SCRATCH (VOIDmode))), note);
4090 emit_libcall_block (insns, temp, valreg, note);
4094 else if (flags & (ECF_CONST | ECF_PURE))
4096 /* Otherwise, just write out the sequence without a note. */
4097 rtx insns = get_insns ();
4104 /* Copy the value to the right place. */
4105 if (outmode != VOIDmode && retval)
4111 if (value != mem_value)
4112 emit_move_insn (value, mem_value);
4114 else if (value != 0)
4115 emit_move_insn (value, hard_libcall_value (outmode));
4117 value = hard_libcall_value (outmode);
4120 if (ACCUMULATE_OUTGOING_ARGS)
4122 #ifdef REG_PARM_STACK_SPACE
4125 enum machine_mode save_mode = GET_MODE (save_area);
4126 #ifdef ARGS_GROW_DOWNWARD
4128 = gen_rtx_MEM (save_mode,
4129 memory_address (save_mode,
4130 plus_constant (argblock,
4134 = gen_rtx_MEM (save_mode,
4135 memory_address (save_mode,
4136 plus_constant (argblock, low_to_save)));
4139 set_mem_align (stack_area, PARM_BOUNDARY);
4140 if (save_mode != BLKmode)
4141 emit_move_insn (stack_area, save_area);
4143 emit_block_move (stack_area, validize_mem (save_area),
4144 GEN_INT (high_to_save - low_to_save + 1));
4148 /* If we saved any argument areas, restore them. */
4149 for (count = 0; count < nargs; count++)
4150 if (argvec[count].save_area)
4152 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4154 = gen_rtx_MEM (save_mode,
4157 plus_constant (argblock,
4158 argvec[count].offset.constant)));
4160 emit_move_insn (stack_area, argvec[count].save_area);
4163 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4164 stack_usage_map = initial_stack_usage_map;
4171 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4172 (emitting the queue unless NO_QUEUE is nonzero),
4173 for a value of mode OUTMODE,
4174 with NARGS different arguments, passed as alternating rtx values
4175 and machine_modes to convert them to.
4176 The rtx values should have been passed through protect_from_queue already.
4178 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4179 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4180 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4181 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4182 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4183 or other LCT_ value for other types of library calls. */
4186 emit_library_call VPARAMS((rtx orgfun, enum libcall_type fn_type,
4187 enum machine_mode outmode, int nargs, ...))
4190 VA_FIXEDARG (p, rtx, orgfun);
4191 VA_FIXEDARG (p, int, fn_type);
4192 VA_FIXEDARG (p, enum machine_mode, outmode);
4193 VA_FIXEDARG (p, int, nargs);
4195 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4200 /* Like emit_library_call except that an extra argument, VALUE,
4201 comes second and says where to store the result.
4202 (If VALUE is zero, this function chooses a convenient way
4203 to return the value.
4205 This function returns an rtx for where the value is to be found.
4206 If VALUE is nonzero, VALUE is returned. */
4209 emit_library_call_value VPARAMS((rtx orgfun, rtx value,
4210 enum libcall_type fn_type,
4211 enum machine_mode outmode, int nargs, ...))
4216 VA_FIXEDARG (p, rtx, orgfun);
4217 VA_FIXEDARG (p, rtx, value);
4218 VA_FIXEDARG (p, int, fn_type);
4219 VA_FIXEDARG (p, enum machine_mode, outmode);
4220 VA_FIXEDARG (p, int, nargs);
4222 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4230 /* Store a single argument for a function call
4231 into the register or memory area where it must be passed.
4232 *ARG describes the argument value and where to pass it.
4234 ARGBLOCK is the address of the stack-block for all the arguments,
4235 or 0 on a machine where arguments are pushed individually.
4237 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4238 so must be careful about how the stack is used.
4240 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4241 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4242 that we need not worry about saving and restoring the stack.
4244 FNDECL is the declaration of the function we are calling.
4246 Return non-zero if this arg should cause sibcall failure,
4250 store_one_arg (arg, argblock, flags, variable_size, reg_parm_stack_space)
4251 struct arg_data *arg;
4254 int variable_size ATTRIBUTE_UNUSED;
4255 int reg_parm_stack_space;
4257 tree pval = arg->tree_value;
4261 int i, lower_bound = 0, upper_bound = 0;
4262 int sibcall_failure = 0;
4264 if (TREE_CODE (pval) == ERROR_MARK)
4267 /* Push a new temporary level for any temporaries we make for
4271 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4273 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4274 save any previous data at that location. */
4275 if (argblock && ! variable_size && arg->stack)
4277 #ifdef ARGS_GROW_DOWNWARD
4278 /* stack_slot is negative, but we want to index stack_usage_map
4279 with positive values. */
4280 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4281 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4285 lower_bound = upper_bound - arg->size.constant;
4287 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4288 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4292 upper_bound = lower_bound + arg->size.constant;
4295 for (i = lower_bound; i < upper_bound; i++)
4296 if (stack_usage_map[i]
4297 /* Don't store things in the fixed argument area at this point;
4298 it has already been saved. */
4299 && i > reg_parm_stack_space)
4302 if (i != upper_bound)
4304 /* We need to make a save area. See what mode we can make it. */
4305 enum machine_mode save_mode
4306 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
4308 = gen_rtx_MEM (save_mode,
4309 memory_address (save_mode,
4310 XEXP (arg->stack_slot, 0)));
4312 if (save_mode == BLKmode)
4314 tree ot = TREE_TYPE (arg->tree_value);
4315 tree nt = build_qualified_type (ot, (TYPE_QUALS (ot)
4316 | TYPE_QUAL_CONST));
4318 arg->save_area = assign_temp (nt, 0, 1, 1);
4319 preserve_temp_slots (arg->save_area);
4320 emit_block_move (validize_mem (arg->save_area), stack_area,
4321 expr_size (arg->tree_value));
4325 arg->save_area = gen_reg_rtx (save_mode);
4326 emit_move_insn (arg->save_area, stack_area);
4330 /* Now that we have saved any slots that will be overwritten by this
4331 store, mark all slots this store will use. We must do this before
4332 we actually expand the argument since the expansion itself may
4333 trigger library calls which might need to use the same stack slot. */
4334 if (argblock && ! variable_size && arg->stack)
4335 for (i = lower_bound; i < upper_bound; i++)
4336 stack_usage_map[i] = 1;
4339 /* If this isn't going to be placed on both the stack and in registers,
4340 set up the register and number of words. */
4341 if (! arg->pass_on_stack)
4342 reg = arg->reg, partial = arg->partial;
4344 if (reg != 0 && partial == 0)
4345 /* Being passed entirely in a register. We shouldn't be called in
4349 /* If this arg needs special alignment, don't load the registers
4351 if (arg->n_aligned_regs != 0)
4354 /* If this is being passed partially in a register, we can't evaluate
4355 it directly into its stack slot. Otherwise, we can. */
4356 if (arg->value == 0)
4358 /* stack_arg_under_construction is nonzero if a function argument is
4359 being evaluated directly into the outgoing argument list and
4360 expand_call must take special action to preserve the argument list
4361 if it is called recursively.
4363 For scalar function arguments stack_usage_map is sufficient to
4364 determine which stack slots must be saved and restored. Scalar
4365 arguments in general have pass_on_stack == 0.
4367 If this argument is initialized by a function which takes the
4368 address of the argument (a C++ constructor or a C function
4369 returning a BLKmode structure), then stack_usage_map is
4370 insufficient and expand_call must push the stack around the
4371 function call. Such arguments have pass_on_stack == 1.
4373 Note that it is always safe to set stack_arg_under_construction,
4374 but this generates suboptimal code if set when not needed. */
4376 if (arg->pass_on_stack)
4377 stack_arg_under_construction++;
4379 arg->value = expand_expr (pval,
4381 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4382 ? NULL_RTX : arg->stack,
4385 /* If we are promoting object (or for any other reason) the mode
4386 doesn't agree, convert the mode. */
4388 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4389 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4390 arg->value, arg->unsignedp);
4392 if (arg->pass_on_stack)
4393 stack_arg_under_construction--;
4396 /* Don't allow anything left on stack from computation
4397 of argument to alloca. */
4398 if (flags & ECF_MAY_BE_ALLOCA)
4399 do_pending_stack_adjust ();
4401 if (arg->value == arg->stack)
4402 /* If the value is already in the stack slot, we are done. */
4404 else if (arg->mode != BLKmode)
4408 /* Argument is a scalar, not entirely passed in registers.
4409 (If part is passed in registers, arg->partial says how much
4410 and emit_push_insn will take care of putting it there.)
4412 Push it, and if its size is less than the
4413 amount of space allocated to it,
4414 also bump stack pointer by the additional space.
4415 Note that in C the default argument promotions
4416 will prevent such mismatches. */
4418 size = GET_MODE_SIZE (arg->mode);
4419 /* Compute how much space the push instruction will push.
4420 On many machines, pushing a byte will advance the stack
4421 pointer by a halfword. */
4422 #ifdef PUSH_ROUNDING
4423 size = PUSH_ROUNDING (size);
4427 /* Compute how much space the argument should get:
4428 round up to a multiple of the alignment for arguments. */
4429 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4430 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4431 / (PARM_BOUNDARY / BITS_PER_UNIT))
4432 * (PARM_BOUNDARY / BITS_PER_UNIT));
4434 /* This isn't already where we want it on the stack, so put it there.
4435 This can either be done with push or copy insns. */
4436 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX, 0,
4437 partial, reg, used - size, argblock,
4438 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
4439 ARGS_SIZE_RTX (arg->alignment_pad));
4443 /* BLKmode, at least partly to be pushed. */
4448 /* Pushing a nonscalar.
4449 If part is passed in registers, PARTIAL says how much
4450 and emit_push_insn will take care of putting it there. */
4452 /* Round its size up to a multiple
4453 of the allocation unit for arguments. */
4455 if (arg->size.var != 0)
4458 size_rtx = ARGS_SIZE_RTX (arg->size);
4462 /* PUSH_ROUNDING has no effect on us, because
4463 emit_push_insn for BLKmode is careful to avoid it. */
4464 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
4465 + partial * UNITS_PER_WORD);
4466 size_rtx = expr_size (pval);
4469 if ((flags & ECF_SIBCALL) && GET_CODE (arg->value) == MEM)
4471 /* emit_push_insn might not work properly if arg->value and
4472 argblock + arg->offset areas overlap. */
4476 if (XEXP (x, 0) == current_function_internal_arg_pointer
4477 || (GET_CODE (XEXP (x, 0)) == PLUS
4478 && XEXP (XEXP (x, 0), 0) ==
4479 current_function_internal_arg_pointer
4480 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT))
4482 if (XEXP (x, 0) != current_function_internal_arg_pointer)
4483 i = INTVAL (XEXP (XEXP (x, 0), 1));
4485 /* expand_call should ensure this */
4486 if (arg->offset.var || GET_CODE (size_rtx) != CONST_INT)
4489 if (arg->offset.constant > i)
4491 if (arg->offset.constant < i + INTVAL (size_rtx))
4492 sibcall_failure = 1;
4494 else if (arg->offset.constant < i)
4496 if (i < arg->offset.constant + INTVAL (size_rtx))
4497 sibcall_failure = 1;
4502 /* Special handling is required if part of the parameter lies in the
4503 register parameter area. The argument may be copied into the stack
4504 slot using memcpy(), but the original contents of the register
4505 parameter area will be restored after the memcpy() call.
4507 To ensure that the part that lies in the register parameter area
4508 is copied correctly, we emit a separate push for that part. This
4509 push should be small enough to avoid a call to memcpy(). */
4510 #ifndef STACK_PARMS_IN_REG_PARM_AREA
4511 if (arg->reg && arg->pass_on_stack)
4516 if (arg->offset.constant < reg_parm_stack_space && arg->offset.var)
4517 error ("variable offset is passed partially in stack and in reg");
4518 else if (arg->offset.constant < reg_parm_stack_space && arg->size.var)
4519 error ("variable size is passed partially in stack and in reg");
4520 else if (arg->offset.constant < reg_parm_stack_space
4521 && ((arg->offset.constant + arg->size.constant)
4522 > reg_parm_stack_space))
4524 rtx size_rtx1 = GEN_INT (reg_parm_stack_space - arg->offset.constant);
4525 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx1,
4526 TYPE_ALIGN (TREE_TYPE (pval)), partial, reg,
4527 excess, argblock, ARGS_SIZE_RTX (arg->offset),
4528 reg_parm_stack_space,
4529 ARGS_SIZE_RTX (arg->alignment_pad));
4534 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4535 TYPE_ALIGN (TREE_TYPE (pval)), partial, reg, excess,
4536 argblock, ARGS_SIZE_RTX (arg->offset),
4537 reg_parm_stack_space,
4538 ARGS_SIZE_RTX (arg->alignment_pad));
4541 /* Unless this is a partially-in-register argument, the argument is now
4544 ??? Note that this can change arg->value from arg->stack to
4545 arg->stack_slot and it matters when they are not the same.
4546 It isn't totally clear that this is correct in all cases. */
4548 arg->value = arg->stack_slot;
4550 /* Once we have pushed something, pops can't safely
4551 be deferred during the rest of the arguments. */
4554 /* ANSI doesn't require a sequence point here,
4555 but PCC has one, so this will avoid some problems. */
4558 /* Free any temporary slots made in processing this argument. Show
4559 that we might have taken the address of something and pushed that
4561 preserve_temp_slots (NULL_RTX);
4565 return sibcall_failure;