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 && ! (ecf_flags & ECF_SP_DEPRESSED))
651 if (flag_defer_pop && inhibit_defer_pop == 0
652 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
653 pending_stack_adjust += rounded_stack_size;
655 adjust_stack (rounded_stack_size_rtx);
658 /* When we accumulate outgoing args, we must avoid any stack manipulations.
659 Restore the stack pointer to its original value now. Usually
660 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
661 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
662 popping variants of functions exist as well.
664 ??? We may optimize similar to defer_pop above, but it is
665 probably not worthwhile.
667 ??? It will be worthwhile to enable combine_stack_adjustments even for
670 anti_adjust_stack (GEN_INT (n_popped));
673 /* Determine if the function identified by NAME and FNDECL is one with
674 special properties we wish to know about.
676 For example, if the function might return more than one time (setjmp), then
677 set RETURNS_TWICE to a nonzero value.
679 Similarly set LONGJMP for if the function is in the longjmp family.
681 Set MALLOC for any of the standard memory allocation functions which
682 allocate from the heap.
684 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
685 space from the stack such as alloca. */
688 special_function_p (fndecl, flags)
692 if (! (flags & ECF_MALLOC)
693 && fndecl && DECL_NAME (fndecl)
694 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
695 /* Exclude functions not at the file scope, or not `extern',
696 since they are not the magic functions we would otherwise
698 && DECL_CONTEXT (fndecl) == NULL_TREE && TREE_PUBLIC (fndecl))
700 const char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
701 const char *tname = name;
703 /* We assume that alloca will always be called by name. It
704 makes no sense to pass it as a pointer-to-function to
705 anything that does not understand its behavior. */
706 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
708 && ! strcmp (name, "alloca"))
709 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
711 && ! strcmp (name, "__builtin_alloca"))))
712 flags |= ECF_MAY_BE_ALLOCA;
714 /* Disregard prefix _, __ or __x. */
717 if (name[1] == '_' && name[2] == 'x')
719 else if (name[1] == '_')
728 && (! strcmp (tname, "setjmp")
729 || ! strcmp (tname, "setjmp_syscall")))
731 && ! strcmp (tname, "sigsetjmp"))
733 && ! strcmp (tname, "savectx")))
734 flags |= ECF_RETURNS_TWICE;
737 && ! strcmp (tname, "siglongjmp"))
738 flags |= ECF_LONGJMP;
740 else if ((tname[0] == 'q' && tname[1] == 's'
741 && ! strcmp (tname, "qsetjmp"))
742 || (tname[0] == 'v' && tname[1] == 'f'
743 && ! strcmp (tname, "vfork")))
744 flags |= ECF_RETURNS_TWICE;
746 else if (tname[0] == 'l' && tname[1] == 'o'
747 && ! strcmp (tname, "longjmp"))
748 flags |= ECF_LONGJMP;
750 else if ((tname[0] == 'f' && tname[1] == 'o'
751 && ! strcmp (tname, "fork"))
752 /* Linux specific: __clone. check NAME to insist on the
753 leading underscores, to avoid polluting the ISO / POSIX
755 || (name[0] == '_' && name[1] == '_'
756 && ! strcmp (tname, "clone"))
757 || (tname[0] == 'e' && tname[1] == 'x' && tname[2] == 'e'
758 && tname[3] == 'c' && (tname[4] == 'l' || tname[4] == 'v')
760 || ((tname[5] == 'p' || tname[5] == 'e')
761 && tname[6] == '\0'))))
762 flags |= ECF_FORK_OR_EXEC;
764 /* Do not add any more malloc-like functions to this list,
765 instead mark them as malloc functions using the malloc attribute.
766 Note, realloc is not suitable for attribute malloc since
767 it may return the same address across multiple calls.
768 C++ operator new is not suitable because it is not required
769 to return a unique pointer; indeed, the standard placement new
770 just returns its argument. */
771 else if (TYPE_MODE (TREE_TYPE (TREE_TYPE (fndecl))) == Pmode
772 && (! strcmp (tname, "malloc")
773 || ! strcmp (tname, "calloc")
774 || ! strcmp (tname, "strdup")))
780 /* Return nonzero when tree represent call to longjmp. */
783 setjmp_call_p (fndecl)
786 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
789 /* Detect flags (function attributes) from the function type node. */
792 flags_from_decl_or_type (exp)
797 /* ??? We can't set IS_MALLOC for function types? */
800 /* The function exp may have the `malloc' attribute. */
801 if (DECL_P (exp) && DECL_IS_MALLOC (exp))
804 /* The function exp may have the `pure' attribute. */
805 if (DECL_P (exp) && DECL_IS_PURE (exp))
808 if (TREE_NOTHROW (exp))
809 flags |= ECF_NOTHROW;
812 if (TREE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
815 if (TREE_THIS_VOLATILE (exp))
816 flags |= ECF_NORETURN;
821 /* Precompute all register parameters as described by ARGS, storing values
822 into fields within the ARGS array.
824 NUM_ACTUALS indicates the total number elements in the ARGS array.
826 Set REG_PARM_SEEN if we encounter a register parameter. */
829 precompute_register_parameters (num_actuals, args, reg_parm_seen)
831 struct arg_data *args;
838 for (i = 0; i < num_actuals; i++)
839 if (args[i].reg != 0 && ! args[i].pass_on_stack)
843 if (args[i].value == 0)
846 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
848 preserve_temp_slots (args[i].value);
851 /* ANSI doesn't require a sequence point here,
852 but PCC has one, so this will avoid some problems. */
856 /* If we are to promote the function arg to a wider mode,
859 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
861 = convert_modes (args[i].mode,
862 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
863 args[i].value, args[i].unsignedp);
865 /* If the value is expensive, and we are inside an appropriately
866 short loop, put the value into a pseudo and then put the pseudo
869 For small register classes, also do this if this call uses
870 register parameters. This is to avoid reload conflicts while
871 loading the parameters registers. */
873 if ((! (GET_CODE (args[i].value) == REG
874 || (GET_CODE (args[i].value) == SUBREG
875 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
876 && args[i].mode != BLKmode
877 && rtx_cost (args[i].value, SET) > COSTS_N_INSNS (1)
878 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
879 || preserve_subexpressions_p ()))
880 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
884 #ifdef REG_PARM_STACK_SPACE
886 /* The argument list is the property of the called routine and it
887 may clobber it. If the fixed area has been used for previous
888 parameters, we must save and restore it. */
891 save_fixed_argument_area (reg_parm_stack_space, argblock,
892 low_to_save, high_to_save)
893 int reg_parm_stack_space;
899 rtx save_area = NULL_RTX;
901 /* Compute the boundary of the that needs to be saved, if any. */
902 #ifdef ARGS_GROW_DOWNWARD
903 for (i = 0; i < reg_parm_stack_space + 1; i++)
905 for (i = 0; i < reg_parm_stack_space; i++)
908 if (i >= highest_outgoing_arg_in_use
909 || stack_usage_map[i] == 0)
912 if (*low_to_save == -1)
918 if (*low_to_save >= 0)
920 int num_to_save = *high_to_save - *low_to_save + 1;
921 enum machine_mode save_mode
922 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
925 /* If we don't have the required alignment, must do this in BLKmode. */
926 if ((*low_to_save & (MIN (GET_MODE_SIZE (save_mode),
927 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
930 #ifdef ARGS_GROW_DOWNWARD
932 = gen_rtx_MEM (save_mode,
933 memory_address (save_mode,
934 plus_constant (argblock,
937 stack_area = gen_rtx_MEM (save_mode,
938 memory_address (save_mode,
939 plus_constant (argblock,
943 set_mem_align (stack_area, PARM_BOUNDARY);
944 if (save_mode == BLKmode)
946 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
947 /* Cannot use emit_block_move here because it can be done by a
948 library call which in turn gets into this place again and deadly
949 infinite recursion happens. */
950 move_by_pieces (validize_mem (save_area), stack_area, num_to_save,
955 save_area = gen_reg_rtx (save_mode);
956 emit_move_insn (save_area, stack_area);
964 restore_fixed_argument_area (save_area, argblock, high_to_save, low_to_save)
970 enum machine_mode save_mode = GET_MODE (save_area);
971 #ifdef ARGS_GROW_DOWNWARD
973 = gen_rtx_MEM (save_mode,
974 memory_address (save_mode,
975 plus_constant (argblock,
979 = gen_rtx_MEM (save_mode,
980 memory_address (save_mode,
981 plus_constant (argblock,
985 if (save_mode != BLKmode)
986 emit_move_insn (stack_area, save_area);
988 /* Cannot use emit_block_move here because it can be done by a library
989 call which in turn gets into this place again and deadly infinite
990 recursion happens. */
991 move_by_pieces (stack_area, validize_mem (save_area),
992 high_to_save - low_to_save + 1, PARM_BOUNDARY);
994 #endif /* REG_PARM_STACK_SPACE */
996 /* If any elements in ARGS refer to parameters that are to be passed in
997 registers, but not in memory, and whose alignment does not permit a
998 direct copy into registers. Copy the values into a group of pseudos
999 which we will later copy into the appropriate hard registers.
1001 Pseudos for each unaligned argument will be stored into the array
1002 args[argnum].aligned_regs. The caller is responsible for deallocating
1003 the aligned_regs array if it is nonzero. */
1006 store_unaligned_arguments_into_pseudos (args, num_actuals)
1007 struct arg_data *args;
1012 for (i = 0; i < num_actuals; i++)
1013 if (args[i].reg != 0 && ! args[i].pass_on_stack
1014 && args[i].mode == BLKmode
1015 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1016 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1018 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1019 int big_endian_correction = 0;
1021 args[i].n_aligned_regs
1022 = args[i].partial ? args[i].partial
1023 : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1025 args[i].aligned_regs = (rtx *) xmalloc (sizeof (rtx)
1026 * args[i].n_aligned_regs);
1028 /* Structures smaller than a word are aligned to the least
1029 significant byte (to the right). On a BYTES_BIG_ENDIAN machine,
1030 this means we must skip the empty high order bytes when
1031 calculating the bit offset. */
1032 if (BYTES_BIG_ENDIAN && bytes < UNITS_PER_WORD)
1033 big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1035 for (j = 0; j < args[i].n_aligned_regs; j++)
1037 rtx reg = gen_reg_rtx (word_mode);
1038 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1039 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1041 args[i].aligned_regs[j] = reg;
1043 /* There is no need to restrict this code to loading items
1044 in TYPE_ALIGN sized hunks. The bitfield instructions can
1045 load up entire word sized registers efficiently.
1047 ??? This may not be needed anymore.
1048 We use to emit a clobber here but that doesn't let later
1049 passes optimize the instructions we emit. By storing 0 into
1050 the register later passes know the first AND to zero out the
1051 bitfield being set in the register is unnecessary. The store
1052 of 0 will be deleted as will at least the first AND. */
1054 emit_move_insn (reg, const0_rtx);
1056 bytes -= bitsize / BITS_PER_UNIT;
1057 store_bit_field (reg, bitsize, big_endian_correction, word_mode,
1058 extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1059 word_mode, word_mode,
1066 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1069 NUM_ACTUALS is the total number of parameters.
1071 N_NAMED_ARGS is the total number of named arguments.
1073 FNDECL is the tree code for the target of this call (if known)
1075 ARGS_SO_FAR holds state needed by the target to know where to place
1078 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1079 for arguments which are passed in registers.
1081 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1082 and may be modified by this routine.
1084 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1085 flags which may may be modified by this routine. */
1088 initialize_argument_information (num_actuals, args, args_size, n_named_args,
1089 actparms, fndecl, args_so_far,
1090 reg_parm_stack_space, old_stack_level,
1091 old_pending_adj, must_preallocate,
1093 int num_actuals ATTRIBUTE_UNUSED;
1094 struct arg_data *args;
1095 struct args_size *args_size;
1096 int n_named_args ATTRIBUTE_UNUSED;
1099 CUMULATIVE_ARGS *args_so_far;
1100 int reg_parm_stack_space;
1101 rtx *old_stack_level;
1102 int *old_pending_adj;
1103 int *must_preallocate;
1106 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1109 /* Count arg position in order args appear. */
1112 struct args_size alignment_pad;
1116 args_size->constant = 0;
1119 /* In this loop, we consider args in the order they are written.
1120 We fill up ARGS from the front or from the back if necessary
1121 so that in any case the first arg to be pushed ends up at the front. */
1123 if (PUSH_ARGS_REVERSED)
1125 i = num_actuals - 1, inc = -1;
1126 /* In this case, must reverse order of args
1127 so that we compute and push the last arg first. */
1134 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1135 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1137 tree type = TREE_TYPE (TREE_VALUE (p));
1139 enum machine_mode mode;
1141 args[i].tree_value = TREE_VALUE (p);
1143 /* Replace erroneous argument with constant zero. */
1144 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1145 args[i].tree_value = integer_zero_node, type = integer_type_node;
1147 /* If TYPE is a transparent union, pass things the way we would
1148 pass the first field of the union. We have already verified that
1149 the modes are the same. */
1150 if (TREE_CODE (type) == UNION_TYPE && TYPE_TRANSPARENT_UNION (type))
1151 type = TREE_TYPE (TYPE_FIELDS (type));
1153 /* Decide where to pass this arg.
1155 args[i].reg is nonzero if all or part is passed in registers.
1157 args[i].partial is nonzero if part but not all is passed in registers,
1158 and the exact value says how many words are passed in registers.
1160 args[i].pass_on_stack is nonzero if the argument must at least be
1161 computed on the stack. It may then be loaded back into registers
1162 if args[i].reg is nonzero.
1164 These decisions are driven by the FUNCTION_... macros and must agree
1165 with those made by function.c. */
1167 /* See if this argument should be passed by invisible reference. */
1168 if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1169 && contains_placeholder_p (TYPE_SIZE (type)))
1170 || TREE_ADDRESSABLE (type)
1171 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1172 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
1173 type, argpos < n_named_args)
1177 /* If we're compiling a thunk, pass through invisible
1178 references instead of making a copy. */
1179 if (current_function_is_thunk
1180 #ifdef FUNCTION_ARG_CALLEE_COPIES
1181 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
1182 type, argpos < n_named_args)
1183 /* If it's in a register, we must make a copy of it too. */
1184 /* ??? Is this a sufficient test? Is there a better one? */
1185 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1186 && REG_P (DECL_RTL (args[i].tree_value)))
1187 && ! TREE_ADDRESSABLE (type))
1191 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1192 new object from the argument. If we are passing by
1193 invisible reference, the callee will do that for us, so we
1194 can strip off the TARGET_EXPR. This is not always safe,
1195 but it is safe in the only case where this is a useful
1196 optimization; namely, when the argument is a plain object.
1197 In that case, the frontend is just asking the backend to
1198 make a bitwise copy of the argument. */
1200 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
1201 && (DECL_P (TREE_OPERAND (args[i].tree_value, 1)))
1202 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
1203 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
1205 args[i].tree_value = build1 (ADDR_EXPR,
1206 build_pointer_type (type),
1207 args[i].tree_value);
1208 type = build_pointer_type (type);
1212 /* We make a copy of the object and pass the address to the
1213 function being called. */
1216 if (!COMPLETE_TYPE_P (type)
1217 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1218 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1219 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1220 STACK_CHECK_MAX_VAR_SIZE))))
1222 /* This is a variable-sized object. Make space on the stack
1224 rtx size_rtx = expr_size (TREE_VALUE (p));
1226 if (*old_stack_level == 0)
1228 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1229 *old_pending_adj = pending_stack_adjust;
1230 pending_stack_adjust = 0;
1233 copy = gen_rtx_MEM (BLKmode,
1234 allocate_dynamic_stack_space
1235 (size_rtx, NULL_RTX, TYPE_ALIGN (type)));
1236 set_mem_attributes (copy, type, 1);
1239 copy = assign_temp (type, 0, 1, 0);
1241 store_expr (args[i].tree_value, copy, 0);
1242 *ecf_flags &= ~(ECF_CONST | ECF_PURE);
1244 args[i].tree_value = build1 (ADDR_EXPR,
1245 build_pointer_type (type),
1246 make_tree (type, copy));
1247 type = build_pointer_type (type);
1251 mode = TYPE_MODE (type);
1252 unsignedp = TREE_UNSIGNED (type);
1254 #ifdef PROMOTE_FUNCTION_ARGS
1255 mode = promote_mode (type, mode, &unsignedp, 1);
1258 args[i].unsignedp = unsignedp;
1259 args[i].mode = mode;
1261 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1262 argpos < n_named_args);
1263 #ifdef FUNCTION_INCOMING_ARG
1264 /* If this is a sibling call and the machine has register windows, the
1265 register window has to be unwinded before calling the routine, so
1266 arguments have to go into the incoming registers. */
1267 args[i].tail_call_reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1268 argpos < n_named_args);
1270 args[i].tail_call_reg = args[i].reg;
1273 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1276 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1277 argpos < n_named_args);
1280 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1282 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1283 it means that we are to pass this arg in the register(s) designated
1284 by the PARALLEL, but also to pass it in the stack. */
1285 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1286 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1287 args[i].pass_on_stack = 1;
1289 /* If this is an addressable type, we must preallocate the stack
1290 since we must evaluate the object into its final location.
1292 If this is to be passed in both registers and the stack, it is simpler
1294 if (TREE_ADDRESSABLE (type)
1295 || (args[i].pass_on_stack && args[i].reg != 0))
1296 *must_preallocate = 1;
1298 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1299 we cannot consider this function call constant. */
1300 if (TREE_ADDRESSABLE (type))
1301 *ecf_flags &= ~(ECF_CONST | ECF_PURE);
1303 /* Compute the stack-size of this argument. */
1304 if (args[i].reg == 0 || args[i].partial != 0
1305 || reg_parm_stack_space > 0
1306 || args[i].pass_on_stack)
1307 locate_and_pad_parm (mode, type,
1308 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1313 fndecl, args_size, &args[i].offset,
1314 &args[i].size, &alignment_pad);
1316 #ifndef ARGS_GROW_DOWNWARD
1317 args[i].slot_offset = *args_size;
1320 args[i].alignment_pad = alignment_pad;
1322 /* If a part of the arg was put into registers,
1323 don't include that part in the amount pushed. */
1324 if (reg_parm_stack_space == 0 && ! args[i].pass_on_stack)
1325 args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1326 / (PARM_BOUNDARY / BITS_PER_UNIT)
1327 * (PARM_BOUNDARY / BITS_PER_UNIT));
1329 /* Update ARGS_SIZE, the total stack space for args so far. */
1331 args_size->constant += args[i].size.constant;
1332 if (args[i].size.var)
1334 ADD_PARM_SIZE (*args_size, args[i].size.var);
1337 /* Since the slot offset points to the bottom of the slot,
1338 we must record it after incrementing if the args grow down. */
1339 #ifdef ARGS_GROW_DOWNWARD
1340 args[i].slot_offset = *args_size;
1342 args[i].slot_offset.constant = -args_size->constant;
1344 SUB_PARM_SIZE (args[i].slot_offset, args_size->var);
1347 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1348 have been used, etc. */
1350 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1351 argpos < n_named_args);
1355 /* Update ARGS_SIZE to contain the total size for the argument block.
1356 Return the original constant component of the argument block's size.
1358 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1359 for arguments passed in registers. */
1362 compute_argument_block_size (reg_parm_stack_space, args_size,
1363 preferred_stack_boundary)
1364 int reg_parm_stack_space;
1365 struct args_size *args_size;
1366 int preferred_stack_boundary ATTRIBUTE_UNUSED;
1368 int unadjusted_args_size = args_size->constant;
1370 /* For accumulate outgoing args mode we don't need to align, since the frame
1371 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1372 backends from generating misaligned frame sizes. */
1373 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1374 preferred_stack_boundary = STACK_BOUNDARY;
1376 /* Compute the actual size of the argument block required. The variable
1377 and constant sizes must be combined, the size may have to be rounded,
1378 and there may be a minimum required size. */
1382 args_size->var = ARGS_SIZE_TREE (*args_size);
1383 args_size->constant = 0;
1385 preferred_stack_boundary /= BITS_PER_UNIT;
1386 if (preferred_stack_boundary > 1)
1388 /* We don't handle this case yet. To handle it correctly we have
1389 to add the delta, round and subtract the delta.
1390 Currently no machine description requires this support. */
1391 if (stack_pointer_delta & (preferred_stack_boundary - 1))
1393 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1396 if (reg_parm_stack_space > 0)
1399 = size_binop (MAX_EXPR, args_size->var,
1400 ssize_int (reg_parm_stack_space));
1402 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1403 /* The area corresponding to register parameters is not to count in
1404 the size of the block we need. So make the adjustment. */
1406 = size_binop (MINUS_EXPR, args_size->var,
1407 ssize_int (reg_parm_stack_space));
1413 preferred_stack_boundary /= BITS_PER_UNIT;
1414 if (preferred_stack_boundary < 1)
1415 preferred_stack_boundary = 1;
1416 args_size->constant = (((args_size->constant
1417 + stack_pointer_delta
1418 + preferred_stack_boundary - 1)
1419 / preferred_stack_boundary
1420 * preferred_stack_boundary)
1421 - stack_pointer_delta);
1423 args_size->constant = MAX (args_size->constant,
1424 reg_parm_stack_space);
1426 #ifdef MAYBE_REG_PARM_STACK_SPACE
1427 if (reg_parm_stack_space == 0)
1428 args_size->constant = 0;
1431 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1432 args_size->constant -= reg_parm_stack_space;
1435 return unadjusted_args_size;
1438 /* Precompute parameters as needed for a function call.
1440 FLAGS is mask of ECF_* constants.
1442 NUM_ACTUALS is the number of arguments.
1444 ARGS is an array containing information for each argument; this
1445 routine fills in the INITIAL_VALUE and VALUE fields for each
1446 precomputed argument. */
1449 precompute_arguments (flags, num_actuals, args)
1452 struct arg_data *args;
1456 /* If this function call is cse'able, precompute all the parameters.
1457 Note that if the parameter is constructed into a temporary, this will
1458 cause an additional copy because the parameter will be constructed
1459 into a temporary location and then copied into the outgoing arguments.
1460 If a parameter contains a call to alloca and this function uses the
1461 stack, precompute the parameter. */
1463 /* If we preallocated the stack space, and some arguments must be passed
1464 on the stack, then we must precompute any parameter which contains a
1465 function call which will store arguments on the stack.
1466 Otherwise, evaluating the parameter may clobber previous parameters
1467 which have already been stored into the stack. (we have code to avoid
1468 such case by saving the outgoing stack arguments, but it results in
1471 for (i = 0; i < num_actuals; i++)
1472 if ((flags & (ECF_CONST | ECF_PURE))
1473 || calls_function (args[i].tree_value, !ACCUMULATE_OUTGOING_ARGS))
1475 enum machine_mode mode;
1477 /* If this is an addressable type, we cannot pre-evaluate it. */
1478 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1484 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1486 preserve_temp_slots (args[i].value);
1489 /* ANSI doesn't require a sequence point here,
1490 but PCC has one, so this will avoid some problems. */
1493 args[i].initial_value = args[i].value
1494 = protect_from_queue (args[i].value, 0);
1496 mode = TYPE_MODE (TREE_TYPE (args[i].tree_value));
1497 if (mode != args[i].mode)
1500 = convert_modes (args[i].mode, mode,
1501 args[i].value, args[i].unsignedp);
1502 #ifdef PROMOTE_FOR_CALL_ONLY
1503 /* CSE will replace this only if it contains args[i].value
1504 pseudo, so convert it down to the declared mode using
1506 if (GET_CODE (args[i].value) == REG
1507 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1509 args[i].initial_value
1510 = gen_lowpart_SUBREG (mode, args[i].value);
1511 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1512 SUBREG_PROMOTED_UNSIGNED_P (args[i].initial_value)
1513 = args[i].unsignedp;
1520 /* Given the current state of MUST_PREALLOCATE and information about
1521 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1522 compute and return the final value for MUST_PREALLOCATE. */
1525 finalize_must_preallocate (must_preallocate, num_actuals, args, args_size)
1526 int must_preallocate;
1528 struct arg_data *args;
1529 struct args_size *args_size;
1531 /* See if we have or want to preallocate stack space.
1533 If we would have to push a partially-in-regs parm
1534 before other stack parms, preallocate stack space instead.
1536 If the size of some parm is not a multiple of the required stack
1537 alignment, we must preallocate.
1539 If the total size of arguments that would otherwise create a copy in
1540 a temporary (such as a CALL) is more than half the total argument list
1541 size, preallocation is faster.
1543 Another reason to preallocate is if we have a machine (like the m88k)
1544 where stack alignment is required to be maintained between every
1545 pair of insns, not just when the call is made. However, we assume here
1546 that such machines either do not have push insns (and hence preallocation
1547 would occur anyway) or the problem is taken care of with
1550 if (! must_preallocate)
1552 int partial_seen = 0;
1553 int copy_to_evaluate_size = 0;
1556 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1558 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1560 else if (partial_seen && args[i].reg == 0)
1561 must_preallocate = 1;
1563 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1564 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1565 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1566 || TREE_CODE (args[i].tree_value) == COND_EXPR
1567 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1568 copy_to_evaluate_size
1569 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1572 if (copy_to_evaluate_size * 2 >= args_size->constant
1573 && args_size->constant > 0)
1574 must_preallocate = 1;
1576 return must_preallocate;
1579 /* If we preallocated stack space, compute the address of each argument
1580 and store it into the ARGS array.
1582 We need not ensure it is a valid memory address here; it will be
1583 validized when it is used.
1585 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1588 compute_argument_addresses (args, argblock, num_actuals)
1589 struct arg_data *args;
1595 rtx arg_reg = argblock;
1596 int i, arg_offset = 0;
1598 if (GET_CODE (argblock) == PLUS)
1599 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1601 for (i = 0; i < num_actuals; i++)
1603 rtx offset = ARGS_SIZE_RTX (args[i].offset);
1604 rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1607 /* Skip this parm if it will not be passed on the stack. */
1608 if (! args[i].pass_on_stack && args[i].reg != 0)
1611 if (GET_CODE (offset) == CONST_INT)
1612 addr = plus_constant (arg_reg, INTVAL (offset));
1614 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1616 addr = plus_constant (addr, arg_offset);
1617 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1618 set_mem_attributes (args[i].stack,
1619 TREE_TYPE (args[i].tree_value), 1);
1621 if (GET_CODE (slot_offset) == CONST_INT)
1622 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1624 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1626 addr = plus_constant (addr, arg_offset);
1627 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1628 set_mem_attributes (args[i].stack_slot,
1629 TREE_TYPE (args[i].tree_value), 1);
1631 /* Function incoming arguments may overlap with sibling call
1632 outgoing arguments and we cannot allow reordering of reads
1633 from function arguments with stores to outgoing arguments
1634 of sibling calls. */
1635 set_mem_alias_set (args[i].stack, 0);
1636 set_mem_alias_set (args[i].stack_slot, 0);
1641 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1642 in a call instruction.
1644 FNDECL is the tree node for the target function. For an indirect call
1645 FNDECL will be NULL_TREE.
1647 EXP is the CALL_EXPR for this call. */
1650 rtx_for_function_call (fndecl, exp)
1656 /* Get the function to call, in the form of RTL. */
1659 /* If this is the first use of the function, see if we need to
1660 make an external definition for it. */
1661 if (! TREE_USED (fndecl))
1663 assemble_external (fndecl);
1664 TREE_USED (fndecl) = 1;
1667 /* Get a SYMBOL_REF rtx for the function address. */
1668 funexp = XEXP (DECL_RTL (fndecl), 0);
1671 /* Generate an rtx (probably a pseudo-register) for the address. */
1676 = expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1677 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1683 /* Do the register loads required for any wholly-register parms or any
1684 parms which are passed both on the stack and in a register. Their
1685 expressions were already evaluated.
1687 Mark all register-parms as living through the call, putting these USE
1688 insns in the CALL_INSN_FUNCTION_USAGE field. */
1691 load_register_parameters (args, num_actuals, call_fusage, flags)
1692 struct arg_data *args;
1699 #ifdef LOAD_ARGS_REVERSED
1700 for (i = num_actuals - 1; i >= 0; i--)
1702 for (i = 0; i < num_actuals; i++)
1705 rtx reg = ((flags & ECF_SIBCALL)
1706 ? args[i].tail_call_reg : args[i].reg);
1707 int partial = args[i].partial;
1712 /* Set to non-negative if must move a word at a time, even if just
1713 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1714 we just use a normal move insn. This value can be zero if the
1715 argument is a zero size structure with no fields. */
1716 nregs = (partial ? partial
1717 : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1718 ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1719 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1722 /* Handle calls that pass values in multiple non-contiguous
1723 locations. The Irix 6 ABI has examples of this. */
1725 if (GET_CODE (reg) == PARALLEL)
1726 emit_group_load (reg, args[i].value,
1727 int_size_in_bytes (TREE_TYPE (args[i].tree_value)));
1729 /* If simple case, just do move. If normal partial, store_one_arg
1730 has already loaded the register for us. In all other cases,
1731 load the register(s) from memory. */
1733 else if (nregs == -1)
1734 emit_move_insn (reg, args[i].value);
1736 /* If we have pre-computed the values to put in the registers in
1737 the case of non-aligned structures, copy them in now. */
1739 else if (args[i].n_aligned_regs != 0)
1740 for (j = 0; j < args[i].n_aligned_regs; j++)
1741 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1742 args[i].aligned_regs[j]);
1744 else if (partial == 0 || args[i].pass_on_stack)
1745 move_block_to_reg (REGNO (reg),
1746 validize_mem (args[i].value), nregs,
1749 /* Handle calls that pass values in multiple non-contiguous
1750 locations. The Irix 6 ABI has examples of this. */
1751 if (GET_CODE (reg) == PARALLEL)
1752 use_group_regs (call_fusage, reg);
1753 else if (nregs == -1)
1754 use_reg (call_fusage, reg);
1756 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1761 /* Try to integrate function. See expand_inline_function for documentation
1762 about the parameters. */
1765 try_to_integrate (fndecl, actparms, target, ignore, type, structure_value_addr)
1771 rtx structure_value_addr;
1776 rtx old_stack_level = 0;
1777 int reg_parm_stack_space = 0;
1779 #ifdef REG_PARM_STACK_SPACE
1780 #ifdef MAYBE_REG_PARM_STACK_SPACE
1781 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1783 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1787 before_call = get_last_insn ();
1789 timevar_push (TV_INTEGRATION);
1791 temp = expand_inline_function (fndecl, actparms, target,
1793 structure_value_addr);
1795 timevar_pop (TV_INTEGRATION);
1797 /* If inlining succeeded, return. */
1798 if (temp != (rtx) (HOST_WIDE_INT) - 1)
1800 if (ACCUMULATE_OUTGOING_ARGS)
1802 /* If the outgoing argument list must be preserved, push
1803 the stack before executing the inlined function if it
1806 for (i = reg_parm_stack_space - 1; i >= 0; i--)
1807 if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
1810 if (stack_arg_under_construction || i >= 0)
1813 = before_call ? NEXT_INSN (before_call) : get_insns ();
1814 rtx insn = NULL_RTX, seq;
1816 /* Look for a call in the inline function code.
1817 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1818 nonzero then there is a call and it is not necessary
1819 to scan the insns. */
1821 if (DECL_SAVED_INSNS (fndecl)->outgoing_args_size == 0)
1822 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1823 if (GET_CODE (insn) == CALL_INSN)
1828 /* Reserve enough stack space so that the largest
1829 argument list of any function call in the inline
1830 function does not overlap the argument list being
1831 evaluated. This is usually an overestimate because
1832 allocate_dynamic_stack_space reserves space for an
1833 outgoing argument list in addition to the requested
1834 space, but there is no way to ask for stack space such
1835 that an argument list of a certain length can be
1838 Add the stack space reserved for register arguments, if
1839 any, in the inline function. What is really needed is the
1840 largest value of reg_parm_stack_space in the inline
1841 function, but that is not available. Using the current
1842 value of reg_parm_stack_space is wrong, but gives
1843 correct results on all supported machines. */
1845 int adjust = (DECL_SAVED_INSNS (fndecl)->outgoing_args_size
1846 + reg_parm_stack_space);
1849 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1850 allocate_dynamic_stack_space (GEN_INT (adjust),
1851 NULL_RTX, BITS_PER_UNIT);
1854 emit_insns_before (seq, first_insn);
1855 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1860 /* If the result is equivalent to TARGET, return TARGET to simplify
1861 checks in store_expr. They can be equivalent but not equal in the
1862 case of a function that returns BLKmode. */
1863 if (temp != target && rtx_equal_p (temp, target))
1868 /* If inlining failed, mark FNDECL as needing to be compiled
1869 separately after all. If function was declared inline,
1871 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1872 && optimize > 0 && !TREE_ADDRESSABLE (fndecl))
1874 warning_with_decl (fndecl, "inlining failed in call to `%s'");
1875 warning ("called from here");
1877 mark_addressable (fndecl);
1878 return (rtx) (HOST_WIDE_INT) - 1;
1881 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1882 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1883 bytes, then we would need to push some additional bytes to pad the
1884 arguments. So, we compute an adjust to the stack pointer for an
1885 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1886 bytes. Then, when the arguments are pushed the stack will be perfectly
1887 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1888 be popped after the call. Returns the adjustment. */
1891 combine_pending_stack_adjustment_and_call (unadjusted_args_size,
1893 preferred_unit_stack_boundary)
1894 int unadjusted_args_size;
1895 struct args_size *args_size;
1896 int preferred_unit_stack_boundary;
1898 /* The number of bytes to pop so that the stack will be
1899 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1900 HOST_WIDE_INT adjustment;
1901 /* The alignment of the stack after the arguments are pushed, if we
1902 just pushed the arguments without adjust the stack here. */
1903 HOST_WIDE_INT unadjusted_alignment;
1905 unadjusted_alignment
1906 = ((stack_pointer_delta + unadjusted_args_size)
1907 % preferred_unit_stack_boundary);
1909 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1910 as possible -- leaving just enough left to cancel out the
1911 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1912 PENDING_STACK_ADJUST is non-negative, and congruent to
1913 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1915 /* Begin by trying to pop all the bytes. */
1916 unadjusted_alignment
1917 = (unadjusted_alignment
1918 - (pending_stack_adjust % preferred_unit_stack_boundary));
1919 adjustment = pending_stack_adjust;
1920 /* Push enough additional bytes that the stack will be aligned
1921 after the arguments are pushed. */
1922 if (preferred_unit_stack_boundary > 1)
1924 if (unadjusted_alignment > 0)
1925 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1927 adjustment += unadjusted_alignment;
1930 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1931 bytes after the call. The right number is the entire
1932 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1933 by the arguments in the first place. */
1935 = pending_stack_adjust - adjustment + unadjusted_args_size;
1940 /* Scan X expression if it does not dereference any argument slots
1941 we already clobbered by tail call arguments (as noted in stored_args_map
1943 Return non-zero if X expression dereferences such argument slots,
1947 check_sibcall_argument_overlap_1 (x)
1958 code = GET_CODE (x);
1962 if (XEXP (x, 0) == current_function_internal_arg_pointer)
1964 else if (GET_CODE (XEXP (x, 0)) == PLUS
1965 && XEXP (XEXP (x, 0), 0) ==
1966 current_function_internal_arg_pointer
1967 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
1968 i = INTVAL (XEXP (XEXP (x, 0), 1));
1972 #ifdef ARGS_GROW_DOWNWARD
1973 i = -i - GET_MODE_SIZE (GET_MODE (x));
1976 for (k = 0; k < GET_MODE_SIZE (GET_MODE (x)); k++)
1977 if (i + k < stored_args_map->n_bits
1978 && TEST_BIT (stored_args_map, i + k))
1984 /* Scan all subexpressions. */
1985 fmt = GET_RTX_FORMAT (code);
1986 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
1990 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
1993 else if (*fmt == 'E')
1995 for (j = 0; j < XVECLEN (x, i); j++)
1996 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2003 /* Scan sequence after INSN if it does not dereference any argument slots
2004 we already clobbered by tail call arguments (as noted in stored_args_map
2005 bitmap). Add stack slots for ARG to stored_args_map bitmap afterwards.
2006 Return non-zero if sequence after INSN dereferences such argument slots,
2010 check_sibcall_argument_overlap (insn, arg)
2012 struct arg_data *arg;
2016 if (insn == NULL_RTX)
2017 insn = get_insns ();
2019 insn = NEXT_INSN (insn);
2021 for (; insn; insn = NEXT_INSN (insn))
2023 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2026 #ifdef ARGS_GROW_DOWNWARD
2027 low = -arg->slot_offset.constant - arg->size.constant;
2029 low = arg->slot_offset.constant;
2032 for (high = low + arg->size.constant; low < high; low++)
2033 SET_BIT (stored_args_map, low);
2034 return insn != NULL_RTX;
2037 /* Generate all the code for a function call
2038 and return an rtx for its value.
2039 Store the value in TARGET (specified as an rtx) if convenient.
2040 If the value is stored in TARGET then TARGET is returned.
2041 If IGNORE is nonzero, then we ignore the value of the function call. */
2044 expand_call (exp, target, ignore)
2049 /* Nonzero if we are currently expanding a call. */
2050 static int currently_expanding_call = 0;
2052 /* List of actual parameters. */
2053 tree actparms = TREE_OPERAND (exp, 1);
2054 /* RTX for the function to be called. */
2056 /* Sequence of insns to perform a tail recursive "call". */
2057 rtx tail_recursion_insns = NULL_RTX;
2058 /* Sequence of insns to perform a normal "call". */
2059 rtx normal_call_insns = NULL_RTX;
2060 /* Sequence of insns to perform a tail recursive "call". */
2061 rtx tail_call_insns = NULL_RTX;
2062 /* Data type of the function. */
2064 /* Declaration of the function being called,
2065 or 0 if the function is computed (not known by name). */
2068 int try_tail_call = 1;
2069 int try_tail_recursion = 1;
2072 /* Register in which non-BLKmode value will be returned,
2073 or 0 if no value or if value is BLKmode. */
2075 /* Address where we should return a BLKmode value;
2076 0 if value not BLKmode. */
2077 rtx structure_value_addr = 0;
2078 /* Nonzero if that address is being passed by treating it as
2079 an extra, implicit first parameter. Otherwise,
2080 it is passed by being copied directly into struct_value_rtx. */
2081 int structure_value_addr_parm = 0;
2082 /* Size of aggregate value wanted, or zero if none wanted
2083 or if we are using the non-reentrant PCC calling convention
2084 or expecting the value in registers. */
2085 HOST_WIDE_INT struct_value_size = 0;
2086 /* Nonzero if called function returns an aggregate in memory PCC style,
2087 by returning the address of where to find it. */
2088 int pcc_struct_value = 0;
2090 /* Number of actual parameters in this call, including struct value addr. */
2092 /* Number of named args. Args after this are anonymous ones
2093 and they must all go on the stack. */
2096 /* Vector of information about each argument.
2097 Arguments are numbered in the order they will be pushed,
2098 not the order they are written. */
2099 struct arg_data *args;
2101 /* Total size in bytes of all the stack-parms scanned so far. */
2102 struct args_size args_size;
2103 struct args_size adjusted_args_size;
2104 /* Size of arguments before any adjustments (such as rounding). */
2105 int unadjusted_args_size;
2106 /* Data on reg parms scanned so far. */
2107 CUMULATIVE_ARGS args_so_far;
2108 /* Nonzero if a reg parm has been scanned. */
2110 /* Nonzero if this is an indirect function call. */
2112 /* Nonzero if we must avoid push-insns in the args for this call.
2113 If stack space is allocated for register parameters, but not by the
2114 caller, then it is preallocated in the fixed part of the stack frame.
2115 So the entire argument block must then be preallocated (i.e., we
2116 ignore PUSH_ROUNDING in that case). */
2118 int must_preallocate = !PUSH_ARGS;
2120 /* Size of the stack reserved for parameter registers. */
2121 int reg_parm_stack_space = 0;
2123 /* Address of space preallocated for stack parms
2124 (on machines that lack push insns), or 0 if space not preallocated. */
2127 /* Mask of ECF_ flags. */
2129 /* Nonzero if this is a call to an inline function. */
2130 int is_integrable = 0;
2131 #ifdef REG_PARM_STACK_SPACE
2132 /* Define the boundary of the register parm stack space that needs to be
2134 int low_to_save = -1, high_to_save;
2135 rtx save_area = 0; /* Place that it is saved */
2138 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2139 char *initial_stack_usage_map = stack_usage_map;
2140 int old_stack_arg_under_construction = 0;
2142 rtx old_stack_level = 0;
2143 int old_pending_adj = 0;
2144 int old_inhibit_defer_pop = inhibit_defer_pop;
2145 int old_stack_allocated;
2147 tree p = TREE_OPERAND (exp, 0);
2149 /* The alignment of the stack, in bits. */
2150 HOST_WIDE_INT preferred_stack_boundary;
2151 /* The alignment of the stack, in bytes. */
2152 HOST_WIDE_INT preferred_unit_stack_boundary;
2154 /* See if this is "nothrow" function call. */
2155 if (TREE_NOTHROW (exp))
2156 flags |= ECF_NOTHROW;
2158 /* See if we can find a DECL-node for the actual function.
2159 As a result, decide whether this is a call to an integrable function. */
2161 fndecl = get_callee_fndecl (exp);
2165 && fndecl != current_function_decl
2166 && DECL_INLINE (fndecl)
2167 && DECL_SAVED_INSNS (fndecl)
2168 && DECL_SAVED_INSNS (fndecl)->inlinable)
2170 else if (! TREE_ADDRESSABLE (fndecl))
2172 /* In case this function later becomes inlinable,
2173 record that there was already a non-inline call to it.
2175 Use abstraction instead of setting TREE_ADDRESSABLE
2177 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2180 warning_with_decl (fndecl, "can't inline call to `%s'");
2181 warning ("called from here");
2183 mark_addressable (fndecl);
2186 flags |= flags_from_decl_or_type (fndecl);
2189 /* If we don't have specific function to call, see if we have a
2190 attributes set in the type. */
2192 flags |= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p)));
2194 /* Mark if the function returns with the stack pointer depressed. */
2195 if (TREE_CODE (TREE_TYPE (TREE_TYPE (p))) == FUNCTION_TYPE
2196 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (TREE_TYPE (p))))
2198 flags |= ECF_SP_DEPRESSED;
2199 flags &= ~(ECF_PURE | ECF_CONST);
2202 #ifdef REG_PARM_STACK_SPACE
2203 #ifdef MAYBE_REG_PARM_STACK_SPACE
2204 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
2206 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2210 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2211 if (reg_parm_stack_space > 0 && PUSH_ARGS)
2212 must_preallocate = 1;
2215 /* Warn if this value is an aggregate type,
2216 regardless of which calling convention we are using for it. */
2217 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2218 warning ("function call has aggregate value");
2220 /* Set up a place to return a structure. */
2222 /* Cater to broken compilers. */
2223 if (aggregate_value_p (exp))
2225 /* This call returns a big structure. */
2226 flags &= ~(ECF_CONST | ECF_PURE);
2228 #ifdef PCC_STATIC_STRUCT_RETURN
2230 pcc_struct_value = 1;
2231 /* Easier than making that case work right. */
2234 /* In case this is a static function, note that it has been
2236 if (! TREE_ADDRESSABLE (fndecl))
2237 mark_addressable (fndecl);
2241 #else /* not PCC_STATIC_STRUCT_RETURN */
2243 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2245 if (target && GET_CODE (target) == MEM)
2246 structure_value_addr = XEXP (target, 0);
2249 /* For variable-sized objects, we must be called with a target
2250 specified. If we were to allocate space on the stack here,
2251 we would have no way of knowing when to free it. */
2252 rtx d = assign_temp (TREE_TYPE (exp), 1, 1, 1);
2254 mark_temp_addr_taken (d);
2255 structure_value_addr = XEXP (d, 0);
2259 #endif /* not PCC_STATIC_STRUCT_RETURN */
2262 /* If called function is inline, try to integrate it. */
2266 rtx temp = try_to_integrate (fndecl, actparms, target,
2267 ignore, TREE_TYPE (exp),
2268 structure_value_addr);
2269 if (temp != (rtx) (HOST_WIDE_INT) - 1)
2273 /* Figure out the amount to which the stack should be aligned. */
2274 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2276 /* Operand 0 is a pointer-to-function; get the type of the function. */
2277 funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
2278 if (! POINTER_TYPE_P (funtype))
2280 funtype = TREE_TYPE (funtype);
2282 /* See if this is a call to a function that can return more than once
2283 or a call to longjmp or malloc. */
2284 flags |= special_function_p (fndecl, flags);
2286 if (flags & ECF_MAY_BE_ALLOCA)
2287 current_function_calls_alloca = 1;
2289 /* If struct_value_rtx is 0, it means pass the address
2290 as if it were an extra parameter. */
2291 if (structure_value_addr && struct_value_rtx == 0)
2293 /* If structure_value_addr is a REG other than
2294 virtual_outgoing_args_rtx, we can use always use it. If it
2295 is not a REG, we must always copy it into a register.
2296 If it is virtual_outgoing_args_rtx, we must copy it to another
2297 register in some cases. */
2298 rtx temp = (GET_CODE (structure_value_addr) != REG
2299 || (ACCUMULATE_OUTGOING_ARGS
2300 && stack_arg_under_construction
2301 && structure_value_addr == virtual_outgoing_args_rtx)
2302 ? copy_addr_to_reg (structure_value_addr)
2303 : structure_value_addr);
2306 = tree_cons (error_mark_node,
2307 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2310 structure_value_addr_parm = 1;
2313 /* Count the arguments and set NUM_ACTUALS. */
2314 for (p = actparms, num_actuals = 0; p; p = TREE_CHAIN (p))
2317 /* Compute number of named args.
2318 Normally, don't include the last named arg if anonymous args follow.
2319 We do include the last named arg if STRICT_ARGUMENT_NAMING is nonzero.
2320 (If no anonymous args follow, the result of list_length is actually
2321 one too large. This is harmless.)
2323 If PRETEND_OUTGOING_VARARGS_NAMED is set and STRICT_ARGUMENT_NAMING is
2324 zero, this machine will be able to place unnamed args that were
2325 passed in registers into the stack. So treat all args as named.
2326 This allows the insns emitting for a specific argument list to be
2327 independent of the function declaration.
2329 If PRETEND_OUTGOING_VARARGS_NAMED is not set, we do not have any
2330 reliable way to pass unnamed args in registers, so we must force
2331 them into memory. */
2333 if ((STRICT_ARGUMENT_NAMING
2334 || ! PRETEND_OUTGOING_VARARGS_NAMED)
2335 && TYPE_ARG_TYPES (funtype) != 0)
2337 = (list_length (TYPE_ARG_TYPES (funtype))
2338 /* Don't include the last named arg. */
2339 - (STRICT_ARGUMENT_NAMING ? 0 : 1)
2340 /* Count the struct value address, if it is passed as a parm. */
2341 + structure_value_addr_parm);
2343 /* If we know nothing, treat all args as named. */
2344 n_named_args = num_actuals;
2346 /* Start updating where the next arg would go.
2348 On some machines (such as the PA) indirect calls have a different
2349 calling convention than normal calls. The last argument in
2350 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2352 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, (fndecl == 0));
2354 /* Make a vector to hold all the information about each arg. */
2355 args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
2356 memset ((char *) args, 0, num_actuals * sizeof (struct arg_data));
2358 /* Build up entries in the ARGS array, compute the size of the
2359 arguments into ARGS_SIZE, etc. */
2360 initialize_argument_information (num_actuals, args, &args_size,
2361 n_named_args, actparms, fndecl,
2362 &args_so_far, reg_parm_stack_space,
2363 &old_stack_level, &old_pending_adj,
2364 &must_preallocate, &flags);
2368 /* If this function requires a variable-sized argument list, don't
2369 try to make a cse'able block for this call. We may be able to
2370 do this eventually, but it is too complicated to keep track of
2371 what insns go in the cse'able block and which don't. */
2373 flags &= ~(ECF_CONST | ECF_PURE);
2374 must_preallocate = 1;
2377 /* Now make final decision about preallocating stack space. */
2378 must_preallocate = finalize_must_preallocate (must_preallocate,
2382 /* If the structure value address will reference the stack pointer, we
2383 must stabilize it. We don't need to do this if we know that we are
2384 not going to adjust the stack pointer in processing this call. */
2386 if (structure_value_addr
2387 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2388 || reg_mentioned_p (virtual_outgoing_args_rtx,
2389 structure_value_addr))
2391 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2392 structure_value_addr = copy_to_reg (structure_value_addr);
2394 /* Tail calls can make things harder to debug, and we're traditionally
2395 pushed these optimizations into -O2. Don't try if we're already
2396 expanding a call, as that means we're an argument. Don't try if
2397 there's cleanups, as we know there's code to follow the call.
2399 If rtx_equal_function_value_matters is false, that means we've
2400 finished with regular parsing. Which means that some of the
2401 machinery we use to generate tail-calls is no longer in place.
2402 This is most often true of sjlj-exceptions, which we couldn't
2403 tail-call to anyway. */
2405 if (currently_expanding_call++ != 0
2406 || !flag_optimize_sibling_calls
2407 || !rtx_equal_function_value_matters
2408 || any_pending_cleanups (1)
2410 try_tail_call = try_tail_recursion = 0;
2412 /* Tail recursion fails, when we are not dealing with recursive calls. */
2413 if (!try_tail_recursion
2414 || TREE_CODE (TREE_OPERAND (exp, 0)) != ADDR_EXPR
2415 || TREE_OPERAND (TREE_OPERAND (exp, 0), 0) != current_function_decl)
2416 try_tail_recursion = 0;
2418 /* Rest of purposes for tail call optimizations to fail. */
2420 #ifdef HAVE_sibcall_epilogue
2421 !HAVE_sibcall_epilogue
2426 /* Doing sibling call optimization needs some work, since
2427 structure_value_addr can be allocated on the stack.
2428 It does not seem worth the effort since few optimizable
2429 sibling calls will return a structure. */
2430 || structure_value_addr != NULL_RTX
2431 /* If the register holding the address is a callee saved
2432 register, then we lose. We have no way to prevent that,
2433 so we only allow calls to named functions. */
2434 /* ??? This could be done by having the insn constraints
2435 use a register class that is all call-clobbered. Any
2436 reload insns generated to fix things up would appear
2437 before the sibcall_epilogue. */
2438 || fndecl == NULL_TREE
2439 || (flags & (ECF_RETURNS_TWICE | ECF_LONGJMP))
2440 || TREE_THIS_VOLATILE (fndecl)
2441 || !FUNCTION_OK_FOR_SIBCALL (fndecl)
2442 /* If this function requires more stack slots than the current
2443 function, we cannot change it into a sibling call. */
2444 || args_size.constant > current_function_args_size
2445 /* If the callee pops its own arguments, then it must pop exactly
2446 the same number of arguments as the current function. */
2447 || RETURN_POPS_ARGS (fndecl, funtype, args_size.constant)
2448 != RETURN_POPS_ARGS (current_function_decl,
2449 TREE_TYPE (current_function_decl),
2450 current_function_args_size))
2453 if (try_tail_call || try_tail_recursion)
2456 actparms = NULL_TREE;
2457 /* Ok, we're going to give the tail call the old college try.
2458 This means we're going to evaluate the function arguments
2459 up to three times. There are two degrees of badness we can
2460 encounter, those that can be unsaved and those that can't.
2461 (See unsafe_for_reeval commentary for details.)
2463 Generate a new argument list. Pass safe arguments through
2464 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2465 For hard badness, evaluate them now and put their resulting
2466 rtx in a temporary VAR_DECL.
2468 initialize_argument_information has ordered the array for the
2469 order to be pushed, and we must remember this when reconstructing
2470 the original argument order. */
2472 if (PUSH_ARGS_REVERSED)
2481 i = num_actuals - 1;
2485 for (; i != end; i += inc)
2487 switch (unsafe_for_reeval (args[i].tree_value))
2492 case 1: /* Mildly unsafe. */
2493 args[i].tree_value = unsave_expr (args[i].tree_value);
2496 case 2: /* Wildly unsafe. */
2498 tree var = build_decl (VAR_DECL, NULL_TREE,
2499 TREE_TYPE (args[i].tree_value));
2501 expand_expr (args[i].tree_value, NULL_RTX,
2502 VOIDmode, EXPAND_NORMAL));
2503 args[i].tree_value = var;
2510 /* We need to build actparms for optimize_tail_recursion. We can
2511 safely trash away TREE_PURPOSE, since it is unused by this
2513 if (try_tail_recursion)
2514 actparms = tree_cons (NULL_TREE, args[i].tree_value, actparms);
2516 /* Expanding one of those dangerous arguments could have added
2517 cleanups, but otherwise give it a whirl. */
2518 if (any_pending_cleanups (1))
2519 try_tail_call = try_tail_recursion = 0;
2522 /* Generate a tail recursion sequence when calling ourselves. */
2524 if (try_tail_recursion)
2526 /* We want to emit any pending stack adjustments before the tail
2527 recursion "call". That way we know any adjustment after the tail
2528 recursion call can be ignored if we indeed use the tail recursion
2530 int save_pending_stack_adjust = pending_stack_adjust;
2531 int save_stack_pointer_delta = stack_pointer_delta;
2533 /* Emit any queued insns now; otherwise they would end up in
2534 only one of the alternates. */
2537 /* Use a new sequence to hold any RTL we generate. We do not even
2538 know if we will use this RTL yet. The final decision can not be
2539 made until after RTL generation for the entire function is
2542 /* If expanding any of the arguments creates cleanups, we can't
2543 do a tailcall. So, we'll need to pop the pending cleanups
2544 list. If, however, all goes well, and there are no cleanups
2545 then the call to expand_start_target_temps will have no
2547 expand_start_target_temps ();
2548 if (optimize_tail_recursion (actparms, get_last_insn ()))
2550 if (any_pending_cleanups (1))
2551 try_tail_call = try_tail_recursion = 0;
2553 tail_recursion_insns = get_insns ();
2555 expand_end_target_temps ();
2558 /* Restore the original pending stack adjustment for the sibling and
2559 normal call cases below. */
2560 pending_stack_adjust = save_pending_stack_adjust;
2561 stack_pointer_delta = save_stack_pointer_delta;
2564 if (profile_arc_flag && (flags & ECF_FORK_OR_EXEC))
2566 /* A fork duplicates the profile information, and an exec discards
2567 it. We can't rely on fork/exec to be paired. So write out the
2568 profile information we have gathered so far, and clear it. */
2569 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2570 is subject to race conditions, just as with multithreaded
2573 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__bb_fork_func"),
2578 /* Ensure current function's preferred stack boundary is at least
2579 what we need. We don't have to increase alignment for recursive
2581 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2582 && fndecl != current_function_decl)
2583 cfun->preferred_stack_boundary = preferred_stack_boundary;
2585 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2587 function_call_count++;
2589 /* We want to make two insn chains; one for a sibling call, the other
2590 for a normal call. We will select one of the two chains after
2591 initial RTL generation is complete. */
2592 for (pass = 0; pass < 2; pass++)
2594 int sibcall_failure = 0;
2595 /* We want to emit any pending stack adjustments before the tail
2596 recursion "call". That way we know any adjustment after the tail
2597 recursion call can be ignored if we indeed use the tail recursion
2599 int save_pending_stack_adjust = 0;
2600 int save_stack_pointer_delta = 0;
2602 rtx before_call, next_arg_reg;
2606 if (! try_tail_call)
2609 /* Emit any queued insns now; otherwise they would end up in
2610 only one of the alternates. */
2613 /* State variables we need to save and restore between
2615 save_pending_stack_adjust = pending_stack_adjust;
2616 save_stack_pointer_delta = stack_pointer_delta;
2619 flags &= ~ECF_SIBCALL;
2621 flags |= ECF_SIBCALL;
2623 /* Other state variables that we must reinitialize each time
2624 through the loop (that are not initialized by the loop itself). */
2628 /* Start a new sequence for the normal call case.
2630 From this point on, if the sibling call fails, we want to set
2631 sibcall_failure instead of continuing the loop. */
2636 /* We know at this point that there are not currently any
2637 pending cleanups. If, however, in the process of evaluating
2638 the arguments we were to create some, we'll need to be
2639 able to get rid of them. */
2640 expand_start_target_temps ();
2643 /* Don't let pending stack adjusts add up to too much.
2644 Also, do all pending adjustments now if there is any chance
2645 this might be a call to alloca or if we are expanding a sibling
2647 if (pending_stack_adjust >= 32
2648 || (pending_stack_adjust > 0 && (flags & ECF_MAY_BE_ALLOCA))
2650 do_pending_stack_adjust ();
2652 /* When calling a const function, we must pop the stack args right away,
2653 so that the pop is deleted or moved with the call. */
2654 if (flags & (ECF_CONST | ECF_PURE))
2657 /* Push the temporary stack slot level so that we can free any
2658 temporaries we make. */
2661 #ifdef FINAL_REG_PARM_STACK_SPACE
2662 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2665 /* Precompute any arguments as needed. */
2667 precompute_arguments (flags, num_actuals, args);
2669 /* Now we are about to start emitting insns that can be deleted
2670 if a libcall is deleted. */
2671 if (flags & (ECF_CONST | ECF_PURE | ECF_MALLOC))
2674 adjusted_args_size = args_size;
2675 /* Compute the actual size of the argument block required. The variable
2676 and constant sizes must be combined, the size may have to be rounded,
2677 and there may be a minimum required size. When generating a sibcall
2678 pattern, do not round up, since we'll be re-using whatever space our
2680 unadjusted_args_size
2681 = compute_argument_block_size (reg_parm_stack_space,
2682 &adjusted_args_size,
2684 : preferred_stack_boundary));
2686 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2688 /* The argument block when performing a sibling call is the
2689 incoming argument block. */
2692 argblock = virtual_incoming_args_rtx;
2693 stored_args_map = sbitmap_alloc (args_size.constant);
2694 sbitmap_zero (stored_args_map);
2697 /* If we have no actual push instructions, or shouldn't use them,
2698 make space for all args right now. */
2699 else if (adjusted_args_size.var != 0)
2701 if (old_stack_level == 0)
2703 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2704 old_pending_adj = pending_stack_adjust;
2705 pending_stack_adjust = 0;
2706 /* stack_arg_under_construction says whether a stack arg is
2707 being constructed at the old stack level. Pushing the stack
2708 gets a clean outgoing argument block. */
2709 old_stack_arg_under_construction = stack_arg_under_construction;
2710 stack_arg_under_construction = 0;
2712 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2716 /* Note that we must go through the motions of allocating an argument
2717 block even if the size is zero because we may be storing args
2718 in the area reserved for register arguments, which may be part of
2721 int needed = adjusted_args_size.constant;
2723 /* Store the maximum argument space used. It will be pushed by
2724 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2727 if (needed > current_function_outgoing_args_size)
2728 current_function_outgoing_args_size = needed;
2730 if (must_preallocate)
2732 if (ACCUMULATE_OUTGOING_ARGS)
2734 /* Since the stack pointer will never be pushed, it is
2735 possible for the evaluation of a parm to clobber
2736 something we have already written to the stack.
2737 Since most function calls on RISC machines do not use
2738 the stack, this is uncommon, but must work correctly.
2740 Therefore, we save any area of the stack that was already
2741 written and that we are using. Here we set up to do this
2742 by making a new stack usage map from the old one. The
2743 actual save will be done by store_one_arg.
2745 Another approach might be to try to reorder the argument
2746 evaluations to avoid this conflicting stack usage. */
2748 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2749 /* Since we will be writing into the entire argument area,
2750 the map must be allocated for its entire size, not just
2751 the part that is the responsibility of the caller. */
2752 needed += reg_parm_stack_space;
2755 #ifdef ARGS_GROW_DOWNWARD
2756 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2759 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2763 = (char *) alloca (highest_outgoing_arg_in_use);
2765 if (initial_highest_arg_in_use)
2766 memcpy (stack_usage_map, initial_stack_usage_map,
2767 initial_highest_arg_in_use);
2769 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2770 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2771 (highest_outgoing_arg_in_use
2772 - initial_highest_arg_in_use));
2775 /* The address of the outgoing argument list must not be
2776 copied to a register here, because argblock would be left
2777 pointing to the wrong place after the call to
2778 allocate_dynamic_stack_space below. */
2780 argblock = virtual_outgoing_args_rtx;
2784 if (inhibit_defer_pop == 0)
2786 /* Try to reuse some or all of the pending_stack_adjust
2787 to get this space. */
2789 = (combine_pending_stack_adjustment_and_call
2790 (unadjusted_args_size,
2791 &adjusted_args_size,
2792 preferred_unit_stack_boundary));
2794 /* combine_pending_stack_adjustment_and_call computes
2795 an adjustment before the arguments are allocated.
2796 Account for them and see whether or not the stack
2797 needs to go up or down. */
2798 needed = unadjusted_args_size - needed;
2802 /* We're releasing stack space. */
2803 /* ??? We can avoid any adjustment at all if we're
2804 already aligned. FIXME. */
2805 pending_stack_adjust = -needed;
2806 do_pending_stack_adjust ();
2810 /* We need to allocate space. We'll do that in
2811 push_block below. */
2812 pending_stack_adjust = 0;
2815 /* Special case this because overhead of `push_block' in
2816 this case is non-trivial. */
2818 argblock = virtual_outgoing_args_rtx;
2820 argblock = push_block (GEN_INT (needed), 0, 0);
2822 /* We only really need to call `copy_to_reg' in the case
2823 where push insns are going to be used to pass ARGBLOCK
2824 to a function call in ARGS. In that case, the stack
2825 pointer changes value from the allocation point to the
2826 call point, and hence the value of
2827 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2828 as well always do it. */
2829 argblock = copy_to_reg (argblock);
2831 /* The save/restore code in store_one_arg handles all
2832 cases except one: a constructor call (including a C
2833 function returning a BLKmode struct) to initialize
2835 if (stack_arg_under_construction)
2837 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2838 rtx push_size = GEN_INT (reg_parm_stack_space
2839 + adjusted_args_size.constant);
2841 rtx push_size = GEN_INT (adjusted_args_size.constant);
2843 if (old_stack_level == 0)
2845 emit_stack_save (SAVE_BLOCK, &old_stack_level,
2847 old_pending_adj = pending_stack_adjust;
2848 pending_stack_adjust = 0;
2849 /* stack_arg_under_construction says whether a stack
2850 arg is being constructed at the old stack level.
2851 Pushing the stack gets a clean outgoing argument
2853 old_stack_arg_under_construction
2854 = stack_arg_under_construction;
2855 stack_arg_under_construction = 0;
2856 /* Make a new map for the new argument list. */
2857 stack_usage_map = (char *)
2858 alloca (highest_outgoing_arg_in_use);
2859 memset (stack_usage_map, 0, highest_outgoing_arg_in_use);
2860 highest_outgoing_arg_in_use = 0;
2862 allocate_dynamic_stack_space (push_size, NULL_RTX,
2865 /* If argument evaluation might modify the stack pointer,
2866 copy the address of the argument list to a register. */
2867 for (i = 0; i < num_actuals; i++)
2868 if (args[i].pass_on_stack)
2870 argblock = copy_addr_to_reg (argblock);
2877 compute_argument_addresses (args, argblock, num_actuals);
2879 /* If we push args individually in reverse order, perform stack alignment
2880 before the first push (the last arg). */
2881 if (PUSH_ARGS_REVERSED && argblock == 0
2882 && adjusted_args_size.constant != unadjusted_args_size)
2884 /* When the stack adjustment is pending, we get better code
2885 by combining the adjustments. */
2886 if (pending_stack_adjust
2887 && ! (flags & (ECF_CONST | ECF_PURE))
2888 && ! inhibit_defer_pop)
2890 pending_stack_adjust
2891 = (combine_pending_stack_adjustment_and_call
2892 (unadjusted_args_size,
2893 &adjusted_args_size,
2894 preferred_unit_stack_boundary));
2895 do_pending_stack_adjust ();
2897 else if (argblock == 0)
2898 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2899 - unadjusted_args_size));
2901 /* Now that the stack is properly aligned, pops can't safely
2902 be deferred during the evaluation of the arguments. */
2905 funexp = rtx_for_function_call (fndecl, exp);
2907 /* Figure out the register where the value, if any, will come back. */
2909 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2910 && ! structure_value_addr)
2912 if (pcc_struct_value)
2913 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2914 fndecl, (pass == 0));
2916 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
2919 /* Precompute all register parameters. It isn't safe to compute anything
2920 once we have started filling any specific hard regs. */
2921 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2923 #ifdef REG_PARM_STACK_SPACE
2924 /* Save the fixed argument area if it's part of the caller's frame and
2925 is clobbered by argument setup for this call. */
2926 if (ACCUMULATE_OUTGOING_ARGS && pass)
2927 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2928 &low_to_save, &high_to_save);
2931 /* Now store (and compute if necessary) all non-register parms.
2932 These come before register parms, since they can require block-moves,
2933 which could clobber the registers used for register parms.
2934 Parms which have partial registers are not stored here,
2935 but we do preallocate space here if they want that. */
2937 for (i = 0; i < num_actuals; i++)
2938 if (args[i].reg == 0 || args[i].pass_on_stack)
2940 rtx before_arg = get_last_insn ();
2942 if (store_one_arg (&args[i], argblock, flags,
2943 adjusted_args_size.var != 0,
2944 reg_parm_stack_space)
2946 && check_sibcall_argument_overlap (before_arg,
2948 sibcall_failure = 1;
2951 /* If we have a parm that is passed in registers but not in memory
2952 and whose alignment does not permit a direct copy into registers,
2953 make a group of pseudos that correspond to each register that we
2955 if (STRICT_ALIGNMENT)
2956 store_unaligned_arguments_into_pseudos (args, num_actuals);
2958 /* Now store any partially-in-registers parm.
2959 This is the last place a block-move can happen. */
2961 for (i = 0; i < num_actuals; i++)
2962 if (args[i].partial != 0 && ! args[i].pass_on_stack)
2964 rtx before_arg = get_last_insn ();
2966 if (store_one_arg (&args[i], argblock, flags,
2967 adjusted_args_size.var != 0,
2968 reg_parm_stack_space)
2970 && check_sibcall_argument_overlap (before_arg,
2972 sibcall_failure = 1;
2975 /* If we pushed args in forward order, perform stack alignment
2976 after pushing the last arg. */
2977 if (!PUSH_ARGS_REVERSED && argblock == 0)
2978 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2979 - unadjusted_args_size));
2981 /* If register arguments require space on the stack and stack space
2982 was not preallocated, allocate stack space here for arguments
2983 passed in registers. */
2984 #ifdef OUTGOING_REG_PARM_STACK_SPACE
2985 if (!ACCUMULATE_OUTGOING_ARGS
2986 && must_preallocate == 0 && reg_parm_stack_space > 0)
2987 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
2990 /* Pass the function the address in which to return a
2992 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
2994 emit_move_insn (struct_value_rtx,
2996 force_operand (structure_value_addr,
2999 if (GET_CODE (struct_value_rtx) == REG)
3000 use_reg (&call_fusage, struct_value_rtx);
3003 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
3004 reg_parm_seen, pass == 0);
3006 load_register_parameters (args, num_actuals, &call_fusage, flags);
3008 /* Perform postincrements before actually calling the function. */
3011 /* Save a pointer to the last insn before the call, so that we can
3012 later safely search backwards to find the CALL_INSN. */
3013 before_call = get_last_insn ();
3015 /* Set up next argument register. For sibling calls on machines
3016 with register windows this should be the incoming register. */
3017 #ifdef FUNCTION_INCOMING_ARG
3019 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
3023 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
3026 /* All arguments and registers used for the call must be set up by
3029 /* Stack must be properly aligned now. */
3030 if (pass && stack_pointer_delta % preferred_unit_stack_boundary)
3033 /* Generate the actual call instruction. */
3034 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
3035 adjusted_args_size.constant, struct_value_size,
3036 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3039 /* Verify that we've deallocated all the stack we used. */
3041 && old_stack_allocated != stack_pointer_delta - pending_stack_adjust)
3044 /* If call is cse'able, make appropriate pair of reg-notes around it.
3045 Test valreg so we don't crash; may safely ignore `const'
3046 if return type is void. Disable for PARALLEL return values, because
3047 we have no way to move such values into a pseudo register. */
3049 && (flags & (ECF_CONST | ECF_PURE))
3050 && valreg != 0 && GET_CODE (valreg) != PARALLEL)
3053 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3056 /* Mark the return value as a pointer if needed. */
3057 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3058 mark_reg_pointer (temp, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
3060 /* Construct an "equal form" for the value which mentions all the
3061 arguments in order as well as the function name. */
3062 for (i = 0; i < num_actuals; i++)
3063 note = gen_rtx_EXPR_LIST (VOIDmode, args[i].initial_value, note);
3064 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
3066 insns = get_insns ();
3069 if (flags & ECF_PURE)
3070 note = gen_rtx_EXPR_LIST (VOIDmode,
3071 gen_rtx_USE (VOIDmode,
3072 gen_rtx_MEM (BLKmode,
3073 gen_rtx_SCRATCH (VOIDmode))), note);
3075 emit_libcall_block (insns, temp, valreg, note);
3079 else if (flags & (ECF_CONST | ECF_PURE))
3081 /* Otherwise, just write out the sequence without a note. */
3082 rtx insns = get_insns ();
3087 else if (flags & ECF_MALLOC)
3089 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3092 /* The return value from a malloc-like function is a pointer. */
3093 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3094 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3096 emit_move_insn (temp, valreg);
3098 /* The return value from a malloc-like function can not alias
3100 last = get_last_insn ();
3102 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
3104 /* Write out the sequence. */
3105 insns = get_insns ();
3111 /* For calls to `setjmp', etc., inform flow.c it should complain
3112 if nonvolatile values are live. For functions that cannot return,
3113 inform flow that control does not fall through. */
3115 if ((flags & (ECF_NORETURN | ECF_LONGJMP)) || pass == 0)
3117 /* The barrier must be emitted
3118 immediately after the CALL_INSN. Some ports emit more
3119 than just a CALL_INSN above, so we must search for it here. */
3121 rtx last = get_last_insn ();
3122 while (GET_CODE (last) != CALL_INSN)
3124 last = PREV_INSN (last);
3125 /* There was no CALL_INSN? */
3126 if (last == before_call)
3130 emit_barrier_after (last);
3133 if (flags & ECF_LONGJMP)
3134 current_function_calls_longjmp = 1;
3136 /* If this function is returning into a memory location marked as
3137 readonly, it means it is initializing that location. But we normally
3138 treat functions as not clobbering such locations, so we need to
3139 specify that this one does. */
3140 if (target != 0 && GET_CODE (target) == MEM
3141 && structure_value_addr != 0 && RTX_UNCHANGING_P (target))
3142 emit_insn (gen_rtx_CLOBBER (VOIDmode, target));
3144 /* If value type not void, return an rtx for the value. */
3146 /* If there are cleanups to be called, don't use a hard reg as target.
3147 We need to double check this and see if it matters anymore. */
3148 if (any_pending_cleanups (1))
3150 if (target && REG_P (target)
3151 && REGNO (target) < FIRST_PSEUDO_REGISTER)
3153 sibcall_failure = 1;
3156 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
3159 target = const0_rtx;
3161 else if (structure_value_addr)
3163 if (target == 0 || GET_CODE (target) != MEM)
3166 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3167 memory_address (TYPE_MODE (TREE_TYPE (exp)),
3168 structure_value_addr));
3169 set_mem_attributes (target, exp, 1);
3172 else if (pcc_struct_value)
3174 /* This is the special C++ case where we need to
3175 know what the true target was. We take care to
3176 never use this value more than once in one expression. */
3177 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3178 copy_to_reg (valreg));
3179 set_mem_attributes (target, exp, 1);
3181 /* Handle calls that return values in multiple non-contiguous locations.
3182 The Irix 6 ABI has examples of this. */
3183 else if (GET_CODE (valreg) == PARALLEL)
3187 /* This will only be assigned once, so it can be readonly. */
3188 tree nt = build_qualified_type (TREE_TYPE (exp),
3189 (TYPE_QUALS (TREE_TYPE (exp))
3190 | TYPE_QUAL_CONST));
3192 target = assign_temp (nt, 0, 1, 1);
3193 preserve_temp_slots (target);
3196 if (! rtx_equal_p (target, valreg))
3197 emit_group_store (target, valreg,
3198 int_size_in_bytes (TREE_TYPE (exp)));
3200 /* We can not support sibling calls for this case. */
3201 sibcall_failure = 1;
3204 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
3205 && GET_MODE (target) == GET_MODE (valreg))
3207 /* TARGET and VALREG cannot be equal at this point because the
3208 latter would not have REG_FUNCTION_VALUE_P true, while the
3209 former would if it were referring to the same register.
3211 If they refer to the same register, this move will be a no-op,
3212 except when function inlining is being done. */
3213 emit_move_insn (target, valreg);
3215 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3217 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3219 /* We can not support sibling calls for this case. */
3220 sibcall_failure = 1;
3223 target = copy_to_reg (valreg);
3225 #ifdef PROMOTE_FUNCTION_RETURN
3226 /* If we promoted this return value, make the proper SUBREG. TARGET
3227 might be const0_rtx here, so be careful. */
3228 if (GET_CODE (target) == REG
3229 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3230 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3232 tree type = TREE_TYPE (exp);
3233 int unsignedp = TREE_UNSIGNED (type);
3236 /* If we don't promote as expected, something is wrong. */
3237 if (GET_MODE (target)
3238 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
3241 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3242 && GET_MODE_SIZE (GET_MODE (target))
3243 > GET_MODE_SIZE (TYPE_MODE (type)))
3245 offset = GET_MODE_SIZE (GET_MODE (target))
3246 - GET_MODE_SIZE (TYPE_MODE (type));
3247 if (! BYTES_BIG_ENDIAN)
3248 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3249 else if (! WORDS_BIG_ENDIAN)
3250 offset %= UNITS_PER_WORD;
3252 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3253 SUBREG_PROMOTED_VAR_P (target) = 1;
3254 SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
3258 /* If size of args is variable or this was a constructor call for a stack
3259 argument, restore saved stack-pointer value. */
3261 if (old_stack_level && ! (flags & ECF_SP_DEPRESSED))
3263 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3264 pending_stack_adjust = old_pending_adj;
3265 stack_arg_under_construction = old_stack_arg_under_construction;
3266 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3267 stack_usage_map = initial_stack_usage_map;
3268 sibcall_failure = 1;
3270 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3272 #ifdef REG_PARM_STACK_SPACE
3275 restore_fixed_argument_area (save_area, argblock,
3276 high_to_save, low_to_save);
3280 /* If we saved any argument areas, restore them. */
3281 for (i = 0; i < num_actuals; i++)
3282 if (args[i].save_area)
3284 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3286 = gen_rtx_MEM (save_mode,
3287 memory_address (save_mode,
3288 XEXP (args[i].stack_slot, 0)));
3290 if (save_mode != BLKmode)
3291 emit_move_insn (stack_area, args[i].save_area);
3293 emit_block_move (stack_area,
3294 validize_mem (args[i].save_area),
3295 GEN_INT (args[i].size.constant));
3298 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3299 stack_usage_map = initial_stack_usage_map;
3302 /* If this was alloca, record the new stack level for nonlocal gotos.
3303 Check for the handler slots since we might not have a save area
3304 for non-local gotos. */
3306 if ((flags & ECF_MAY_BE_ALLOCA) && nonlocal_goto_handler_slots != 0)
3307 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3311 /* Free up storage we no longer need. */
3312 for (i = 0; i < num_actuals; ++i)
3313 if (args[i].aligned_regs)
3314 free (args[i].aligned_regs);
3318 /* Undo the fake expand_start_target_temps we did earlier. If
3319 there had been any cleanups created, we've already set
3321 expand_end_target_temps ();
3324 insns = get_insns ();
3329 tail_call_insns = insns;
3331 /* Restore the pending stack adjustment now that we have
3332 finished generating the sibling call sequence. */
3334 pending_stack_adjust = save_pending_stack_adjust;
3335 stack_pointer_delta = save_stack_pointer_delta;
3337 /* Prepare arg structure for next iteration. */
3338 for (i = 0; i < num_actuals; i++)
3341 args[i].aligned_regs = 0;
3345 sbitmap_free (stored_args_map);
3348 normal_call_insns = insns;
3350 /* If something prevents making this a sibling call,
3351 zero out the sequence. */
3352 if (sibcall_failure)
3353 tail_call_insns = NULL_RTX;
3356 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3357 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3358 can happen if the arguments to this function call an inline
3359 function who's expansion contains another CALL_PLACEHOLDER.
3361 If there are any C_Ps in any of these sequences, replace them
3362 with their normal call. */
3364 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3365 if (GET_CODE (insn) == CALL_INSN
3366 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3367 replace_call_placeholder (insn, sibcall_use_normal);
3369 for (insn = tail_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_recursion_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 /* If this was a potential tail recursion site, then emit a
3380 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3381 One of them will be selected later. */
3382 if (tail_recursion_insns || tail_call_insns)
3384 /* The tail recursion label must be kept around. We could expose
3385 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3386 and makes determining true tail recursion sites difficult.
3388 So we set LABEL_PRESERVE_P here, then clear it when we select
3389 one of the call sequences after rtl generation is complete. */
3390 if (tail_recursion_insns)
3391 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3392 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3394 tail_recursion_insns,
3395 tail_recursion_label));
3398 emit_insns (normal_call_insns);
3400 currently_expanding_call--;
3402 /* If this function returns with the stack pointer depressed, ensure
3403 this block saves and restores the stack pointer, show it was
3404 changed, and adjust for any outgoing arg space. */
3405 if (flags & ECF_SP_DEPRESSED)
3407 clear_pending_stack_adjust ();
3408 emit_insn (gen_rtx (CLOBBER, VOIDmode, stack_pointer_rtx));
3409 emit_move_insn (virtual_stack_dynamic_rtx, stack_pointer_rtx);
3410 save_stack_pointer ();
3416 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3417 The RETVAL parameter specifies whether return value needs to be saved, other
3418 parameters are documented in the emit_library_call function below. */
3421 emit_library_call_value_1 (retval, orgfun, value, fn_type, outmode, nargs, p)
3425 enum libcall_type fn_type;
3426 enum machine_mode outmode;
3430 /* Total size in bytes of all the stack-parms scanned so far. */
3431 struct args_size args_size;
3432 /* Size of arguments before any adjustments (such as rounding). */
3433 struct args_size original_args_size;
3438 struct args_size alignment_pad;
3440 CUMULATIVE_ARGS args_so_far;
3444 enum machine_mode mode;
3447 struct args_size offset;
3448 struct args_size size;
3452 int old_inhibit_defer_pop = inhibit_defer_pop;
3453 rtx call_fusage = 0;
3456 int pcc_struct_value = 0;
3457 int struct_value_size = 0;
3459 int reg_parm_stack_space = 0;
3463 #ifdef REG_PARM_STACK_SPACE
3464 /* Define the boundary of the register parm stack space that needs to be
3466 int low_to_save = -1, high_to_save = 0;
3467 rtx save_area = 0; /* Place that it is saved. */
3470 /* Size of the stack reserved for parameter registers. */
3471 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3472 char *initial_stack_usage_map = stack_usage_map;
3474 #ifdef REG_PARM_STACK_SPACE
3475 #ifdef MAYBE_REG_PARM_STACK_SPACE
3476 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3478 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3482 /* By default, library functions can not throw. */
3483 flags = ECF_NOTHROW;
3490 /* Nothing to do here. */
3492 case LCT_CONST_MAKE_BLOCK:
3495 case LCT_PURE_MAKE_BLOCK:
3499 flags |= ECF_NORETURN;
3502 flags = ECF_NORETURN;
3504 case LCT_ALWAYS_RETURN:
3505 flags = ECF_ALWAYS_RETURN;
3507 case LCT_RETURNS_TWICE:
3508 flags = ECF_RETURNS_TWICE;
3513 /* Ensure current function's preferred stack boundary is at least
3515 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3516 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3518 /* If this kind of value comes back in memory,
3519 decide where in memory it should come back. */
3520 if (outmode != VOIDmode && aggregate_value_p (type_for_mode (outmode, 0)))
3522 #ifdef PCC_STATIC_STRUCT_RETURN
3524 = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
3526 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3527 pcc_struct_value = 1;
3529 value = gen_reg_rtx (outmode);
3530 #else /* not PCC_STATIC_STRUCT_RETURN */
3531 struct_value_size = GET_MODE_SIZE (outmode);
3532 if (value != 0 && GET_CODE (value) == MEM)
3535 mem_value = assign_temp (type_for_mode (outmode, 0), 0, 1, 1);
3538 /* This call returns a big structure. */
3539 flags &= ~(ECF_CONST | ECF_PURE);
3542 /* ??? Unfinished: must pass the memory address as an argument. */
3544 /* Copy all the libcall-arguments out of the varargs data
3545 and into a vector ARGVEC.
3547 Compute how to pass each argument. We only support a very small subset
3548 of the full argument passing conventions to limit complexity here since
3549 library functions shouldn't have many args. */
3551 argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
3552 memset ((char *) argvec, 0, (nargs + 1) * sizeof (struct arg));
3554 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3555 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far, outmode, fun);
3557 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
3560 args_size.constant = 0;
3565 /* Now we are about to start emitting insns that can be deleted
3566 if a libcall is deleted. */
3567 if (flags & (ECF_CONST | ECF_PURE))
3572 /* If there's a structure value address to be passed,
3573 either pass it in the special place, or pass it as an extra argument. */
3574 if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
3576 rtx addr = XEXP (mem_value, 0);
3579 /* Make sure it is a reasonable operand for a move or push insn. */
3580 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3581 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3582 addr = force_operand (addr, NULL_RTX);
3584 argvec[count].value = addr;
3585 argvec[count].mode = Pmode;
3586 argvec[count].partial = 0;
3588 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3589 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3590 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3594 locate_and_pad_parm (Pmode, NULL_TREE,
3595 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3598 argvec[count].reg != 0,
3600 NULL_TREE, &args_size, &argvec[count].offset,
3601 &argvec[count].size, &alignment_pad);
3603 if (argvec[count].reg == 0 || argvec[count].partial != 0
3604 || reg_parm_stack_space > 0)
3605 args_size.constant += argvec[count].size.constant;
3607 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3612 for (; count < nargs; count++)
3614 rtx val = va_arg (p, rtx);
3615 enum machine_mode mode = va_arg (p, enum machine_mode);
3617 /* We cannot convert the arg value to the mode the library wants here;
3618 must do it earlier where we know the signedness of the arg. */
3620 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3623 /* On some machines, there's no way to pass a float to a library fcn.
3624 Pass it as a double instead. */
3625 #ifdef LIBGCC_NEEDS_DOUBLE
3626 if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
3627 val = convert_modes (DFmode, SFmode, val, 0), mode = DFmode;
3630 /* There's no need to call protect_from_queue, because
3631 either emit_move_insn or emit_push_insn will do that. */
3633 /* Make sure it is a reasonable operand for a move or push insn. */
3634 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3635 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3636 val = force_operand (val, NULL_RTX);
3638 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3639 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3643 #ifdef FUNCTION_ARG_CALLEE_COPIES
3644 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far, mode,
3649 if (GET_MODE (val) == MEM && ! must_copy)
3653 slot = assign_temp (type_for_mode (mode, 0), 0, 1, 1);
3654 emit_move_insn (slot, val);
3658 tree type = type_for_mode (mode, 0);
3660 slot = gen_rtx_MEM (mode,
3661 expand_expr (build1 (ADDR_EXPR,
3664 make_tree (type, val)),
3665 NULL_RTX, VOIDmode, 0));
3668 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3669 gen_rtx_USE (VOIDmode, slot),
3672 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3673 gen_rtx_CLOBBER (VOIDmode,
3678 val = force_operand (XEXP (slot, 0), NULL_RTX);
3682 argvec[count].value = val;
3683 argvec[count].mode = mode;
3685 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3687 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3688 argvec[count].partial
3689 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3691 argvec[count].partial = 0;
3694 locate_and_pad_parm (mode, NULL_TREE,
3695 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3698 argvec[count].reg != 0,
3700 NULL_TREE, &args_size, &argvec[count].offset,
3701 &argvec[count].size, &alignment_pad);
3703 if (argvec[count].size.var)
3706 if (reg_parm_stack_space == 0 && argvec[count].partial)
3707 argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
3709 if (argvec[count].reg == 0 || argvec[count].partial != 0
3710 || reg_parm_stack_space > 0)
3711 args_size.constant += argvec[count].size.constant;
3713 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3716 #ifdef FINAL_REG_PARM_STACK_SPACE
3717 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3720 /* If this machine requires an external definition for library
3721 functions, write one out. */
3722 assemble_external_libcall (fun);
3724 original_args_size = args_size;
3725 args_size.constant = (((args_size.constant
3726 + stack_pointer_delta
3730 - stack_pointer_delta);
3732 args_size.constant = MAX (args_size.constant,
3733 reg_parm_stack_space);
3735 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3736 args_size.constant -= reg_parm_stack_space;
3739 if (args_size.constant > current_function_outgoing_args_size)
3740 current_function_outgoing_args_size = args_size.constant;
3742 if (ACCUMULATE_OUTGOING_ARGS)
3744 /* Since the stack pointer will never be pushed, it is possible for
3745 the evaluation of a parm to clobber something we have already
3746 written to the stack. Since most function calls on RISC machines
3747 do not use the stack, this is uncommon, but must work correctly.
3749 Therefore, we save any area of the stack that was already written
3750 and that we are using. Here we set up to do this by making a new
3751 stack usage map from the old one.
3753 Another approach might be to try to reorder the argument
3754 evaluations to avoid this conflicting stack usage. */
3756 needed = args_size.constant;
3758 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3759 /* Since we will be writing into the entire argument area, the
3760 map must be allocated for its entire size, not just the part that
3761 is the responsibility of the caller. */
3762 needed += reg_parm_stack_space;
3765 #ifdef ARGS_GROW_DOWNWARD
3766 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3769 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3772 stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
3774 if (initial_highest_arg_in_use)
3775 memcpy (stack_usage_map, initial_stack_usage_map,
3776 initial_highest_arg_in_use);
3778 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3779 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3780 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3783 /* We must be careful to use virtual regs before they're instantiated,
3784 and real regs afterwards. Loop optimization, for example, can create
3785 new libcalls after we've instantiated the virtual regs, and if we
3786 use virtuals anyway, they won't match the rtl patterns. */
3788 if (virtuals_instantiated)
3789 argblock = plus_constant (stack_pointer_rtx, STACK_POINTER_OFFSET);
3791 argblock = virtual_outgoing_args_rtx;
3796 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3799 /* If we push args individually in reverse order, perform stack alignment
3800 before the first push (the last arg). */
3801 if (argblock == 0 && PUSH_ARGS_REVERSED)
3802 anti_adjust_stack (GEN_INT (args_size.constant
3803 - original_args_size.constant));
3805 if (PUSH_ARGS_REVERSED)
3816 #ifdef REG_PARM_STACK_SPACE
3817 if (ACCUMULATE_OUTGOING_ARGS)
3819 /* The argument list is the property of the called routine and it
3820 may clobber it. If the fixed area has been used for previous
3821 parameters, we must save and restore it.
3823 Here we compute the boundary of the that needs to be saved, if any. */
3825 #ifdef ARGS_GROW_DOWNWARD
3826 for (count = 0; count < reg_parm_stack_space + 1; count++)
3828 for (count = 0; count < reg_parm_stack_space; count++)
3831 if (count >= highest_outgoing_arg_in_use
3832 || stack_usage_map[count] == 0)
3835 if (low_to_save == -1)
3836 low_to_save = count;
3838 high_to_save = count;
3841 if (low_to_save >= 0)
3843 int num_to_save = high_to_save - low_to_save + 1;
3844 enum machine_mode save_mode
3845 = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
3848 /* If we don't have the required alignment, must do this in BLKmode. */
3849 if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
3850 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
3851 save_mode = BLKmode;
3853 #ifdef ARGS_GROW_DOWNWARD
3854 stack_area = gen_rtx_MEM (save_mode,
3855 memory_address (save_mode,
3856 plus_constant (argblock,
3859 stack_area = gen_rtx_MEM (save_mode,
3860 memory_address (save_mode,
3861 plus_constant (argblock,
3864 if (save_mode == BLKmode)
3866 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
3867 set_mem_align (save_area, PARM_BOUNDARY);
3868 emit_block_move (validize_mem (save_area), stack_area,
3869 GEN_INT (num_to_save));
3873 save_area = gen_reg_rtx (save_mode);
3874 emit_move_insn (save_area, stack_area);
3880 /* Push the args that need to be pushed. */
3882 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3883 are to be pushed. */
3884 for (count = 0; count < nargs; count++, argnum += inc)
3886 enum machine_mode mode = argvec[argnum].mode;
3887 rtx val = argvec[argnum].value;
3888 rtx reg = argvec[argnum].reg;
3889 int partial = argvec[argnum].partial;
3890 int lower_bound = 0, upper_bound = 0, i;
3892 if (! (reg != 0 && partial == 0))
3894 if (ACCUMULATE_OUTGOING_ARGS)
3896 /* If this is being stored into a pre-allocated, fixed-size,
3897 stack area, save any previous data at that location. */
3899 #ifdef ARGS_GROW_DOWNWARD
3900 /* stack_slot is negative, but we want to index stack_usage_map
3901 with positive values. */
3902 upper_bound = -argvec[argnum].offset.constant + 1;
3903 lower_bound = upper_bound - argvec[argnum].size.constant;
3905 lower_bound = argvec[argnum].offset.constant;
3906 upper_bound = lower_bound + argvec[argnum].size.constant;
3909 for (i = lower_bound; i < upper_bound; i++)
3910 if (stack_usage_map[i]
3911 /* Don't store things in the fixed argument area at this
3912 point; it has already been saved. */
3913 && i > reg_parm_stack_space)
3916 if (i != upper_bound)
3918 /* We need to make a save area. See what mode we can make
3920 enum machine_mode save_mode
3921 = mode_for_size (argvec[argnum].size.constant
3929 plus_constant (argblock,
3930 argvec[argnum].offset.constant)));
3931 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3933 emit_move_insn (argvec[argnum].save_area, stack_area);
3937 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
3938 argblock, GEN_INT (argvec[argnum].offset.constant),
3939 reg_parm_stack_space, ARGS_SIZE_RTX (alignment_pad));
3941 /* Now mark the segment we just used. */
3942 if (ACCUMULATE_OUTGOING_ARGS)
3943 for (i = lower_bound; i < upper_bound; i++)
3944 stack_usage_map[i] = 1;
3950 /* If we pushed args in forward order, perform stack alignment
3951 after pushing the last arg. */
3952 if (argblock == 0 && !PUSH_ARGS_REVERSED)
3953 anti_adjust_stack (GEN_INT (args_size.constant
3954 - original_args_size.constant));
3956 if (PUSH_ARGS_REVERSED)
3961 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0, 0);
3963 /* Now load any reg parms into their regs. */
3965 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3966 are to be pushed. */
3967 for (count = 0; count < nargs; count++, argnum += inc)
3969 rtx val = argvec[argnum].value;
3970 rtx reg = argvec[argnum].reg;
3971 int partial = argvec[argnum].partial;
3973 /* Handle calls that pass values in multiple non-contiguous
3974 locations. The PA64 has examples of this for library calls. */
3975 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3976 emit_group_load (reg, val, GET_MODE_SIZE (GET_MODE (val)));
3977 else if (reg != 0 && partial == 0)
3978 emit_move_insn (reg, val);
3983 /* Any regs containing parms remain in use through the call. */
3984 for (count = 0; count < nargs; count++)
3986 rtx reg = argvec[count].reg;
3987 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3988 use_group_regs (&call_fusage, reg);
3990 use_reg (&call_fusage, reg);
3993 /* Pass the function the address in which to return a structure value. */
3994 if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
3996 emit_move_insn (struct_value_rtx,
3998 force_operand (XEXP (mem_value, 0),
4000 if (GET_CODE (struct_value_rtx) == REG)
4001 use_reg (&call_fusage, struct_value_rtx);
4004 /* Don't allow popping to be deferred, since then
4005 cse'ing of library calls could delete a call and leave the pop. */
4007 valreg = (mem_value == 0 && outmode != VOIDmode
4008 ? hard_libcall_value (outmode) : NULL_RTX);
4010 /* Stack must be properly aligned now. */
4011 if (stack_pointer_delta & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1))
4014 before_call = get_last_insn ();
4016 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4017 will set inhibit_defer_pop to that value. */
4018 /* The return type is needed to decide how many bytes the function pops.
4019 Signedness plays no role in that, so for simplicity, we pretend it's
4020 always signed. We also assume that the list of arguments passed has
4021 no impact, so we pretend it is unknown. */
4024 get_identifier (XSTR (orgfun, 0)),
4025 build_function_type (outmode == VOIDmode ? void_type_node
4026 : type_for_mode (outmode, 0), NULL_TREE),
4027 original_args_size.constant, args_size.constant,
4029 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
4031 old_inhibit_defer_pop + 1, call_fusage, flags);
4033 /* For calls to `setjmp', etc., inform flow.c it should complain
4034 if nonvolatile values are live. For functions that cannot return,
4035 inform flow that control does not fall through. */
4037 if (flags & (ECF_NORETURN | ECF_LONGJMP))
4039 /* The barrier note must be emitted
4040 immediately after the CALL_INSN. Some ports emit more than
4041 just a CALL_INSN above, so we must search for it here. */
4043 rtx last = get_last_insn ();
4044 while (GET_CODE (last) != CALL_INSN)
4046 last = PREV_INSN (last);
4047 /* There was no CALL_INSN? */
4048 if (last == before_call)
4052 emit_barrier_after (last);
4055 /* Now restore inhibit_defer_pop to its actual original value. */
4058 /* If call is cse'able, make appropriate pair of reg-notes around it.
4059 Test valreg so we don't crash; may safely ignore `const'
4060 if return type is void. Disable for PARALLEL return values, because
4061 we have no way to move such values into a pseudo register. */
4062 if ((flags & (ECF_CONST | ECF_PURE))
4063 && valreg != 0 && GET_CODE (valreg) != PARALLEL)
4066 rtx temp = gen_reg_rtx (GET_MODE (valreg));
4070 /* Construct an "equal form" for the value which mentions all the
4071 arguments in order as well as the function name. */
4072 for (i = 0; i < nargs; i++)
4073 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
4074 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
4076 insns = get_insns ();
4079 if (flags & ECF_PURE)
4080 note = gen_rtx_EXPR_LIST (VOIDmode,
4081 gen_rtx_USE (VOIDmode,
4082 gen_rtx_MEM (BLKmode,
4083 gen_rtx_SCRATCH (VOIDmode))), note);
4085 emit_libcall_block (insns, temp, valreg, note);
4089 else if (flags & (ECF_CONST | ECF_PURE))
4091 /* Otherwise, just write out the sequence without a note. */
4092 rtx insns = get_insns ();
4099 /* Copy the value to the right place. */
4100 if (outmode != VOIDmode && retval)
4106 if (value != mem_value)
4107 emit_move_insn (value, mem_value);
4109 else if (value != 0)
4110 emit_move_insn (value, hard_libcall_value (outmode));
4112 value = hard_libcall_value (outmode);
4115 if (ACCUMULATE_OUTGOING_ARGS)
4117 #ifdef REG_PARM_STACK_SPACE
4120 enum machine_mode save_mode = GET_MODE (save_area);
4121 #ifdef ARGS_GROW_DOWNWARD
4123 = gen_rtx_MEM (save_mode,
4124 memory_address (save_mode,
4125 plus_constant (argblock,
4129 = gen_rtx_MEM (save_mode,
4130 memory_address (save_mode,
4131 plus_constant (argblock, low_to_save)));
4134 set_mem_align (stack_area, PARM_BOUNDARY);
4135 if (save_mode != BLKmode)
4136 emit_move_insn (stack_area, save_area);
4138 emit_block_move (stack_area, validize_mem (save_area),
4139 GEN_INT (high_to_save - low_to_save + 1));
4143 /* If we saved any argument areas, restore them. */
4144 for (count = 0; count < nargs; count++)
4145 if (argvec[count].save_area)
4147 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4149 = gen_rtx_MEM (save_mode,
4152 plus_constant (argblock,
4153 argvec[count].offset.constant)));
4155 emit_move_insn (stack_area, argvec[count].save_area);
4158 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4159 stack_usage_map = initial_stack_usage_map;
4166 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4167 (emitting the queue unless NO_QUEUE is nonzero),
4168 for a value of mode OUTMODE,
4169 with NARGS different arguments, passed as alternating rtx values
4170 and machine_modes to convert them to.
4171 The rtx values should have been passed through protect_from_queue already.
4173 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4174 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4175 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4176 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4177 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4178 or other LCT_ value for other types of library calls. */
4181 emit_library_call VPARAMS((rtx orgfun, enum libcall_type fn_type,
4182 enum machine_mode outmode, int nargs, ...))
4185 VA_FIXEDARG (p, rtx, orgfun);
4186 VA_FIXEDARG (p, int, fn_type);
4187 VA_FIXEDARG (p, enum machine_mode, outmode);
4188 VA_FIXEDARG (p, int, nargs);
4190 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4195 /* Like emit_library_call except that an extra argument, VALUE,
4196 comes second and says where to store the result.
4197 (If VALUE is zero, this function chooses a convenient way
4198 to return the value.
4200 This function returns an rtx for where the value is to be found.
4201 If VALUE is nonzero, VALUE is returned. */
4204 emit_library_call_value VPARAMS((rtx orgfun, rtx value,
4205 enum libcall_type fn_type,
4206 enum machine_mode outmode, int nargs, ...))
4211 VA_FIXEDARG (p, rtx, orgfun);
4212 VA_FIXEDARG (p, rtx, value);
4213 VA_FIXEDARG (p, int, fn_type);
4214 VA_FIXEDARG (p, enum machine_mode, outmode);
4215 VA_FIXEDARG (p, int, nargs);
4217 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4225 /* Store a single argument for a function call
4226 into the register or memory area where it must be passed.
4227 *ARG describes the argument value and where to pass it.
4229 ARGBLOCK is the address of the stack-block for all the arguments,
4230 or 0 on a machine where arguments are pushed individually.
4232 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4233 so must be careful about how the stack is used.
4235 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4236 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4237 that we need not worry about saving and restoring the stack.
4239 FNDECL is the declaration of the function we are calling.
4241 Return non-zero if this arg should cause sibcall failure,
4245 store_one_arg (arg, argblock, flags, variable_size, reg_parm_stack_space)
4246 struct arg_data *arg;
4249 int variable_size ATTRIBUTE_UNUSED;
4250 int reg_parm_stack_space;
4252 tree pval = arg->tree_value;
4256 int i, lower_bound = 0, upper_bound = 0;
4257 int sibcall_failure = 0;
4259 if (TREE_CODE (pval) == ERROR_MARK)
4262 /* Push a new temporary level for any temporaries we make for
4266 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4268 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4269 save any previous data at that location. */
4270 if (argblock && ! variable_size && arg->stack)
4272 #ifdef ARGS_GROW_DOWNWARD
4273 /* stack_slot is negative, but we want to index stack_usage_map
4274 with positive values. */
4275 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4276 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4280 lower_bound = upper_bound - arg->size.constant;
4282 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4283 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4287 upper_bound = lower_bound + arg->size.constant;
4290 for (i = lower_bound; i < upper_bound; i++)
4291 if (stack_usage_map[i]
4292 /* Don't store things in the fixed argument area at this point;
4293 it has already been saved. */
4294 && i > reg_parm_stack_space)
4297 if (i != upper_bound)
4299 /* We need to make a save area. See what mode we can make it. */
4300 enum machine_mode save_mode
4301 = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
4303 = gen_rtx_MEM (save_mode,
4304 memory_address (save_mode,
4305 XEXP (arg->stack_slot, 0)));
4307 if (save_mode == BLKmode)
4309 tree ot = TREE_TYPE (arg->tree_value);
4310 tree nt = build_qualified_type (ot, (TYPE_QUALS (ot)
4311 | TYPE_QUAL_CONST));
4313 arg->save_area = assign_temp (nt, 0, 1, 1);
4314 preserve_temp_slots (arg->save_area);
4315 emit_block_move (validize_mem (arg->save_area), stack_area,
4316 expr_size (arg->tree_value));
4320 arg->save_area = gen_reg_rtx (save_mode);
4321 emit_move_insn (arg->save_area, stack_area);
4325 /* Now that we have saved any slots that will be overwritten by this
4326 store, mark all slots this store will use. We must do this before
4327 we actually expand the argument since the expansion itself may
4328 trigger library calls which might need to use the same stack slot. */
4329 if (argblock && ! variable_size && arg->stack)
4330 for (i = lower_bound; i < upper_bound; i++)
4331 stack_usage_map[i] = 1;
4334 /* If this isn't going to be placed on both the stack and in registers,
4335 set up the register and number of words. */
4336 if (! arg->pass_on_stack)
4337 reg = arg->reg, partial = arg->partial;
4339 if (reg != 0 && partial == 0)
4340 /* Being passed entirely in a register. We shouldn't be called in
4344 /* If this arg needs special alignment, don't load the registers
4346 if (arg->n_aligned_regs != 0)
4349 /* If this is being passed partially in a register, we can't evaluate
4350 it directly into its stack slot. Otherwise, we can. */
4351 if (arg->value == 0)
4353 /* stack_arg_under_construction is nonzero if a function argument is
4354 being evaluated directly into the outgoing argument list and
4355 expand_call must take special action to preserve the argument list
4356 if it is called recursively.
4358 For scalar function arguments stack_usage_map is sufficient to
4359 determine which stack slots must be saved and restored. Scalar
4360 arguments in general have pass_on_stack == 0.
4362 If this argument is initialized by a function which takes the
4363 address of the argument (a C++ constructor or a C function
4364 returning a BLKmode structure), then stack_usage_map is
4365 insufficient and expand_call must push the stack around the
4366 function call. Such arguments have pass_on_stack == 1.
4368 Note that it is always safe to set stack_arg_under_construction,
4369 but this generates suboptimal code if set when not needed. */
4371 if (arg->pass_on_stack)
4372 stack_arg_under_construction++;
4374 arg->value = expand_expr (pval,
4376 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4377 ? NULL_RTX : arg->stack,
4380 /* If we are promoting object (or for any other reason) the mode
4381 doesn't agree, convert the mode. */
4383 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4384 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4385 arg->value, arg->unsignedp);
4387 if (arg->pass_on_stack)
4388 stack_arg_under_construction--;
4391 /* Don't allow anything left on stack from computation
4392 of argument to alloca. */
4393 if (flags & ECF_MAY_BE_ALLOCA)
4394 do_pending_stack_adjust ();
4396 if (arg->value == arg->stack)
4397 /* If the value is already in the stack slot, we are done. */
4399 else if (arg->mode != BLKmode)
4403 /* Argument is a scalar, not entirely passed in registers.
4404 (If part is passed in registers, arg->partial says how much
4405 and emit_push_insn will take care of putting it there.)
4407 Push it, and if its size is less than the
4408 amount of space allocated to it,
4409 also bump stack pointer by the additional space.
4410 Note that in C the default argument promotions
4411 will prevent such mismatches. */
4413 size = GET_MODE_SIZE (arg->mode);
4414 /* Compute how much space the push instruction will push.
4415 On many machines, pushing a byte will advance the stack
4416 pointer by a halfword. */
4417 #ifdef PUSH_ROUNDING
4418 size = PUSH_ROUNDING (size);
4422 /* Compute how much space the argument should get:
4423 round up to a multiple of the alignment for arguments. */
4424 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4425 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4426 / (PARM_BOUNDARY / BITS_PER_UNIT))
4427 * (PARM_BOUNDARY / BITS_PER_UNIT));
4429 /* This isn't already where we want it on the stack, so put it there.
4430 This can either be done with push or copy insns. */
4431 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX, 0,
4432 partial, reg, used - size, argblock,
4433 ARGS_SIZE_RTX (arg->offset), reg_parm_stack_space,
4434 ARGS_SIZE_RTX (arg->alignment_pad));
4438 /* BLKmode, at least partly to be pushed. */
4443 /* Pushing a nonscalar.
4444 If part is passed in registers, PARTIAL says how much
4445 and emit_push_insn will take care of putting it there. */
4447 /* Round its size up to a multiple
4448 of the allocation unit for arguments. */
4450 if (arg->size.var != 0)
4453 size_rtx = ARGS_SIZE_RTX (arg->size);
4457 /* PUSH_ROUNDING has no effect on us, because
4458 emit_push_insn for BLKmode is careful to avoid it. */
4459 excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
4460 + partial * UNITS_PER_WORD);
4461 size_rtx = expr_size (pval);
4464 if ((flags & ECF_SIBCALL) && GET_CODE (arg->value) == MEM)
4466 /* emit_push_insn might not work properly if arg->value and
4467 argblock + arg->offset areas overlap. */
4471 if (XEXP (x, 0) == current_function_internal_arg_pointer
4472 || (GET_CODE (XEXP (x, 0)) == PLUS
4473 && XEXP (XEXP (x, 0), 0) ==
4474 current_function_internal_arg_pointer
4475 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT))
4477 if (XEXP (x, 0) != current_function_internal_arg_pointer)
4478 i = INTVAL (XEXP (XEXP (x, 0), 1));
4480 /* expand_call should ensure this */
4481 if (arg->offset.var || GET_CODE (size_rtx) != CONST_INT)
4484 if (arg->offset.constant > i)
4486 if (arg->offset.constant < i + INTVAL (size_rtx))
4487 sibcall_failure = 1;
4489 else if (arg->offset.constant < i)
4491 if (i < arg->offset.constant + INTVAL (size_rtx))
4492 sibcall_failure = 1;
4497 /* Special handling is required if part of the parameter lies in the
4498 register parameter area. The argument may be copied into the stack
4499 slot using memcpy(), but the original contents of the register
4500 parameter area will be restored after the memcpy() call.
4502 To ensure that the part that lies in the register parameter area
4503 is copied correctly, we emit a separate push for that part. This
4504 push should be small enough to avoid a call to memcpy(). */
4505 #ifndef STACK_PARMS_IN_REG_PARM_AREA
4506 if (arg->reg && arg->pass_on_stack)
4511 if (arg->offset.constant < reg_parm_stack_space && arg->offset.var)
4512 error ("variable offset is passed partially in stack and in reg");
4513 else if (arg->offset.constant < reg_parm_stack_space && arg->size.var)
4514 error ("variable size is passed partially in stack and in reg");
4515 else if (arg->offset.constant < reg_parm_stack_space
4516 && ((arg->offset.constant + arg->size.constant)
4517 > reg_parm_stack_space))
4519 rtx size_rtx1 = GEN_INT (reg_parm_stack_space - arg->offset.constant);
4520 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx1,
4521 TYPE_ALIGN (TREE_TYPE (pval)), partial, reg,
4522 excess, argblock, ARGS_SIZE_RTX (arg->offset),
4523 reg_parm_stack_space,
4524 ARGS_SIZE_RTX (arg->alignment_pad));
4529 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4530 TYPE_ALIGN (TREE_TYPE (pval)), partial, reg, excess,
4531 argblock, ARGS_SIZE_RTX (arg->offset),
4532 reg_parm_stack_space,
4533 ARGS_SIZE_RTX (arg->alignment_pad));
4536 /* Unless this is a partially-in-register argument, the argument is now
4539 ??? Note that this can change arg->value from arg->stack to
4540 arg->stack_slot and it matters when they are not the same.
4541 It isn't totally clear that this is correct in all cases. */
4543 arg->value = arg->stack_slot;
4545 /* Once we have pushed something, pops can't safely
4546 be deferred during the rest of the arguments. */
4549 /* ANSI doesn't require a sequence point here,
4550 but PCC has one, so this will avoid some problems. */
4553 /* Free any temporary slots made in processing this argument. Show
4554 that we might have taken the address of something and pushed that
4556 preserve_temp_slots (NULL_RTX);
4560 return sibcall_failure;