1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
24 #include "coretypes.h"
39 #include "langhooks.h"
44 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
45 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
47 /* Data structure and subroutines used within expand_call. */
51 /* Tree node for this argument. */
53 /* Mode for value; TYPE_MODE unless promoted. */
54 enum machine_mode mode;
55 /* Current RTL value for argument, or 0 if it isn't precomputed. */
57 /* Initially-compute RTL value for argument; only for const functions. */
59 /* Register to pass this argument in, 0 if passed on stack, or an
60 PARALLEL if the arg is to be copied into multiple non-contiguous
63 /* Register to pass this argument in when generating tail call sequence.
64 This is not the same register as for normal calls on machines with
67 /* If REG was promoted from the actual mode of the argument expression,
68 indicates whether the promotion is sign- or zero-extended. */
70 /* Number of registers to use. 0 means put the whole arg in registers.
71 Also 0 if not passed in registers. */
73 /* Nonzero if argument must be passed on stack.
74 Note that some arguments may be passed on the stack
75 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
76 pass_on_stack identifies arguments that *cannot* go in registers. */
78 /* Some fields packaged up for locate_and_pad_parm. */
79 struct locate_and_pad_arg_data locate;
80 /* Location on the stack at which parameter should be stored. The store
81 has already been done if STACK == VALUE. */
83 /* Location on the stack of the start of this argument slot. This can
84 differ from STACK if this arg pads downward. This location is known
85 to be aligned to FUNCTION_ARG_BOUNDARY. */
87 /* Place that this stack area has been saved, if needed. */
89 /* If an argument's alignment does not permit direct copying into registers,
90 copy in smaller-sized pieces into pseudos. These are stored in a
91 block pointed to by this field. The next field says how many
92 word-sized pseudos we made. */
97 /* A vector of one char per byte of stack space. A byte if nonzero if
98 the corresponding stack location has been used.
99 This vector is used to prevent a function call within an argument from
100 clobbering any stack already set up. */
101 static char *stack_usage_map;
103 /* Size of STACK_USAGE_MAP. */
104 static int highest_outgoing_arg_in_use;
106 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
107 stack location's tail call argument has been already stored into the stack.
108 This bitmap is used to prevent sibling call optimization if function tries
109 to use parent's incoming argument slots when they have been already
110 overwritten with tail call arguments. */
111 static sbitmap stored_args_map;
113 /* stack_arg_under_construction is nonzero when an argument may be
114 initialized with a constructor call (including a C function that
115 returns a BLKmode struct) and expand_call must take special action
116 to make sure the object being constructed does not overlap the
117 argument list for the constructor call. */
118 int stack_arg_under_construction;
120 static int calls_function (tree, int);
121 static int calls_function_1 (tree, int);
123 static void emit_call_1 (rtx, tree, tree, HOST_WIDE_INT, HOST_WIDE_INT,
124 HOST_WIDE_INT, rtx, rtx, int, rtx, int,
126 static void precompute_register_parameters (int, struct arg_data *, int *);
127 static int store_one_arg (struct arg_data *, rtx, int, int, int);
128 static void store_unaligned_arguments_into_pseudos (struct arg_data *, int);
129 static int finalize_must_preallocate (int, int, struct arg_data *,
131 static void precompute_arguments (int, int, struct arg_data *);
132 static int compute_argument_block_size (int, struct args_size *, int);
133 static void initialize_argument_information (int, struct arg_data *,
134 struct args_size *, int, tree,
135 tree, CUMULATIVE_ARGS *, int,
136 rtx *, int *, int *, int *,
138 static void compute_argument_addresses (struct arg_data *, rtx, int);
139 static rtx rtx_for_function_call (tree, tree);
140 static void load_register_parameters (struct arg_data *, int, rtx *, int,
142 static rtx emit_library_call_value_1 (int, rtx, rtx, enum libcall_type,
143 enum machine_mode, int, va_list);
144 static int special_function_p (tree, int);
145 static rtx try_to_integrate (tree, tree, rtx, int, tree, rtx);
146 static int check_sibcall_argument_overlap_1 (rtx);
147 static int check_sibcall_argument_overlap (rtx, struct arg_data *, int);
149 static int combine_pending_stack_adjustment_and_call (int, struct args_size *,
151 static tree fix_unsafe_tree (tree);
152 static bool shift_returned_value (tree, rtx *);
154 #ifdef REG_PARM_STACK_SPACE
155 static rtx save_fixed_argument_area (int, rtx, int *, int *);
156 static void restore_fixed_argument_area (rtx, rtx, int, int);
159 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
162 If WHICH is 0, return 1 if EXP contains a call to any function.
163 Actually, we only need return 1 if evaluating EXP would require pushing
164 arguments on the stack, but that is too difficult to compute, so we just
165 assume any function call might require the stack. */
167 static tree calls_function_save_exprs;
170 calls_function (tree exp, int which)
174 calls_function_save_exprs = 0;
175 val = calls_function_1 (exp, which);
176 calls_function_save_exprs = 0;
180 /* Recursive function to do the work of above function. */
183 calls_function_1 (tree exp, int which)
186 enum tree_code code = TREE_CODE (exp);
187 int class = TREE_CODE_CLASS (code);
188 int length = first_rtl_op (code);
190 /* If this code is language-specific, we don't know what it will do. */
191 if ((int) code >= NUM_TREE_CODES)
199 else if ((TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))
201 && (TYPE_RETURNS_STACK_DEPRESSED
202 (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))))
204 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
205 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
207 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
209 & ECF_MAY_BE_ALLOCA))
218 for (tem = CONSTRUCTOR_ELTS (exp); tem != 0; tem = TREE_CHAIN (tem))
219 if (calls_function_1 (TREE_VALUE (tem), which))
226 if (SAVE_EXPR_RTL (exp) != 0)
228 if (value_member (exp, calls_function_save_exprs))
230 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
231 calls_function_save_exprs);
232 return (TREE_OPERAND (exp, 0) != 0
233 && calls_function_1 (TREE_OPERAND (exp, 0), which));
240 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
241 if (DECL_INITIAL (local) != 0
242 && calls_function_1 (DECL_INITIAL (local), which))
245 for (subblock = BLOCK_SUBBLOCKS (exp);
247 subblock = TREE_CHAIN (subblock))
248 if (calls_function_1 (subblock, which))
254 for (; exp != 0; exp = TREE_CHAIN (exp))
255 if (calls_function_1 (TREE_VALUE (exp), which))
263 /* Only expressions and blocks can contain calls. */
264 if (! IS_EXPR_CODE_CLASS (class) && class != 'b')
267 for (i = 0; i < length; i++)
268 if (TREE_OPERAND (exp, i) != 0
269 && calls_function_1 (TREE_OPERAND (exp, i), which))
275 /* Force FUNEXP into a form suitable for the address of a CALL,
276 and return that as an rtx. Also load the static chain register
277 if FNDECL is a nested function.
279 CALL_FUSAGE points to a variable holding the prospective
280 CALL_INSN_FUNCTION_USAGE information. */
283 prepare_call_address (rtx funexp, tree fndecl, rtx *call_fusage,
284 int reg_parm_seen, int sibcallp)
286 rtx static_chain_value = 0;
288 funexp = protect_from_queue (funexp, 0);
291 /* Get possible static chain value for nested function in C. */
292 static_chain_value = lookup_static_chain (fndecl);
294 /* Make a valid memory address and copy constants through pseudo-regs,
295 but not for a constant address if -fno-function-cse. */
296 if (GET_CODE (funexp) != SYMBOL_REF)
297 /* If we are using registers for parameters, force the
298 function address into a register now. */
299 funexp = ((SMALL_REGISTER_CLASSES && reg_parm_seen)
300 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
301 : memory_address (FUNCTION_MODE, funexp));
304 #ifndef NO_FUNCTION_CSE
305 if (optimize && ! flag_no_function_cse)
306 #ifdef NO_RECURSIVE_FUNCTION_CSE
307 if (fndecl != current_function_decl)
309 funexp = force_reg (Pmode, funexp);
313 if (static_chain_value != 0)
315 emit_move_insn (static_chain_rtx, static_chain_value);
317 if (GET_CODE (static_chain_rtx) == REG)
318 use_reg (call_fusage, static_chain_rtx);
324 /* Generate instructions to call function FUNEXP,
325 and optionally pop the results.
326 The CALL_INSN is the first insn generated.
328 FNDECL is the declaration node of the function. This is given to the
329 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
331 FUNTYPE is the data type of the function. This is given to the macro
332 RETURN_POPS_ARGS to determine whether this function pops its own args.
333 We used to allow an identifier for library functions, but that doesn't
334 work when the return type is an aggregate type and the calling convention
335 says that the pointer to this aggregate is to be popped by the callee.
337 STACK_SIZE is the number of bytes of arguments on the stack,
338 ROUNDED_STACK_SIZE is that number rounded up to
339 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
340 both to put into the call insn and to generate explicit popping
343 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
344 It is zero if this call doesn't want a structure value.
346 NEXT_ARG_REG is the rtx that results from executing
347 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
348 just after all the args have had their registers assigned.
349 This could be whatever you like, but normally it is the first
350 arg-register beyond those used for args in this call,
351 or 0 if all the arg-registers are used in this call.
352 It is passed on to `gen_call' so you can put this info in the call insn.
354 VALREG is a hard register in which a value is returned,
355 or 0 if the call does not return a value.
357 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
358 the args to this call were processed.
359 We restore `inhibit_defer_pop' to that value.
361 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
362 denote registers used by the called function. */
365 emit_call_1 (rtx funexp, tree fndecl ATTRIBUTE_UNUSED, tree funtype ATTRIBUTE_UNUSED,
366 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED,
367 HOST_WIDE_INT rounded_stack_size,
368 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED,
369 rtx next_arg_reg ATTRIBUTE_UNUSED, rtx valreg,
370 int old_inhibit_defer_pop, rtx call_fusage, int ecf_flags,
371 CUMULATIVE_ARGS *args_so_far ATTRIBUTE_UNUSED)
373 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
375 int already_popped = 0;
376 HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
377 #if defined (HAVE_call) && defined (HAVE_call_value)
378 rtx struct_value_size_rtx;
379 struct_value_size_rtx = GEN_INT (struct_value_size);
382 #ifdef CALL_POPS_ARGS
383 n_popped += CALL_POPS_ARGS (* args_so_far);
386 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
387 and we don't want to load it into a register as an optimization,
388 because prepare_call_address already did it if it should be done. */
389 if (GET_CODE (funexp) != SYMBOL_REF)
390 funexp = memory_address (FUNCTION_MODE, funexp);
392 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
393 if ((ecf_flags & ECF_SIBCALL)
394 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
395 && (n_popped > 0 || stack_size == 0))
397 rtx n_pop = GEN_INT (n_popped);
400 /* If this subroutine pops its own args, record that in the call insn
401 if possible, for the sake of frame pointer elimination. */
404 pat = GEN_SIBCALL_VALUE_POP (valreg,
405 gen_rtx_MEM (FUNCTION_MODE, funexp),
406 rounded_stack_size_rtx, next_arg_reg,
409 pat = GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
410 rounded_stack_size_rtx, next_arg_reg, n_pop);
412 emit_call_insn (pat);
418 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
419 /* If the target has "call" or "call_value" insns, then prefer them
420 if no arguments are actually popped. If the target does not have
421 "call" or "call_value" insns, then we must use the popping versions
422 even if the call has no arguments to pop. */
423 #if defined (HAVE_call) && defined (HAVE_call_value)
424 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
425 && n_popped > 0 && ! (ecf_flags & ECF_SP_DEPRESSED))
427 if (HAVE_call_pop && HAVE_call_value_pop)
430 rtx n_pop = GEN_INT (n_popped);
433 /* If this subroutine pops its own args, record that in the call insn
434 if possible, for the sake of frame pointer elimination. */
437 pat = GEN_CALL_VALUE_POP (valreg,
438 gen_rtx_MEM (FUNCTION_MODE, funexp),
439 rounded_stack_size_rtx, next_arg_reg, n_pop);
441 pat = GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
442 rounded_stack_size_rtx, next_arg_reg, n_pop);
444 emit_call_insn (pat);
450 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
451 if ((ecf_flags & ECF_SIBCALL)
452 && HAVE_sibcall && HAVE_sibcall_value)
455 emit_call_insn (GEN_SIBCALL_VALUE (valreg,
456 gen_rtx_MEM (FUNCTION_MODE, funexp),
457 rounded_stack_size_rtx,
458 next_arg_reg, NULL_RTX));
460 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
461 rounded_stack_size_rtx, next_arg_reg,
462 struct_value_size_rtx));
467 #if defined (HAVE_call) && defined (HAVE_call_value)
468 if (HAVE_call && HAVE_call_value)
471 emit_call_insn (GEN_CALL_VALUE (valreg,
472 gen_rtx_MEM (FUNCTION_MODE, funexp),
473 rounded_stack_size_rtx, next_arg_reg,
476 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
477 rounded_stack_size_rtx, next_arg_reg,
478 struct_value_size_rtx));
484 /* Find the call we just emitted. */
485 call_insn = last_call_insn ();
487 /* Mark memory as used for "pure" function call. */
488 if (ecf_flags & ECF_PURE)
492 gen_rtx_USE (VOIDmode,
493 gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (VOIDmode))),
496 /* Put the register usage information there. */
497 add_function_usage_to (call_insn, call_fusage);
499 /* If this is a const call, then set the insn's unchanging bit. */
500 if (ecf_flags & (ECF_CONST | ECF_PURE))
501 CONST_OR_PURE_CALL_P (call_insn) = 1;
503 /* If this call can't throw, attach a REG_EH_REGION reg note to that
505 if (ecf_flags & ECF_NOTHROW)
506 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_EH_REGION, const0_rtx,
507 REG_NOTES (call_insn));
509 note_eh_region_may_contain_throw ();
511 if (ecf_flags & ECF_NORETURN)
512 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_NORETURN, const0_rtx,
513 REG_NOTES (call_insn));
514 if (ecf_flags & ECF_ALWAYS_RETURN)
515 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_ALWAYS_RETURN, const0_rtx,
516 REG_NOTES (call_insn));
518 if (ecf_flags & ECF_RETURNS_TWICE)
520 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_SETJMP, const0_rtx,
521 REG_NOTES (call_insn));
522 current_function_calls_setjmp = 1;
525 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
527 /* Restore this now, so that we do defer pops for this call's args
528 if the context of the call as a whole permits. */
529 inhibit_defer_pop = old_inhibit_defer_pop;
534 CALL_INSN_FUNCTION_USAGE (call_insn)
535 = gen_rtx_EXPR_LIST (VOIDmode,
536 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
537 CALL_INSN_FUNCTION_USAGE (call_insn));
538 rounded_stack_size -= n_popped;
539 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
540 stack_pointer_delta -= n_popped;
543 if (!ACCUMULATE_OUTGOING_ARGS)
545 /* If returning from the subroutine does not automatically pop the args,
546 we need an instruction to pop them sooner or later.
547 Perhaps do it now; perhaps just record how much space to pop later.
549 If returning from the subroutine does pop the args, indicate that the
550 stack pointer will be changed. */
552 if (rounded_stack_size != 0)
554 if (ecf_flags & (ECF_SP_DEPRESSED | ECF_NORETURN | ECF_LONGJMP))
555 /* Just pretend we did the pop. */
556 stack_pointer_delta -= rounded_stack_size;
557 else if (flag_defer_pop && inhibit_defer_pop == 0
558 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
559 pending_stack_adjust += rounded_stack_size;
561 adjust_stack (rounded_stack_size_rtx);
564 /* When we accumulate outgoing args, we must avoid any stack manipulations.
565 Restore the stack pointer to its original value now. Usually
566 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
567 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
568 popping variants of functions exist as well.
570 ??? We may optimize similar to defer_pop above, but it is
571 probably not worthwhile.
573 ??? It will be worthwhile to enable combine_stack_adjustments even for
576 anti_adjust_stack (GEN_INT (n_popped));
579 /* Determine if the function identified by NAME and FNDECL is one with
580 special properties we wish to know about.
582 For example, if the function might return more than one time (setjmp), then
583 set RETURNS_TWICE to a nonzero value.
585 Similarly set LONGJMP for if the function is in the longjmp family.
587 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
588 space from the stack such as alloca. */
591 special_function_p (tree fndecl, int flags)
593 if (! (flags & ECF_MALLOC)
594 && fndecl && DECL_NAME (fndecl)
595 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
596 /* Exclude functions not at the file scope, or not `extern',
597 since they are not the magic functions we would otherwise
599 FIXME: this should be handled with attributes, not with this
600 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
601 because you can declare fork() inside a function if you
603 && (DECL_CONTEXT (fndecl) == NULL_TREE
604 || TREE_CODE (DECL_CONTEXT (fndecl)) == TRANSLATION_UNIT_DECL)
605 && TREE_PUBLIC (fndecl))
607 const char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
608 const char *tname = name;
610 /* We assume that alloca will always be called by name. It
611 makes no sense to pass it as a pointer-to-function to
612 anything that does not understand its behavior. */
613 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
615 && ! strcmp (name, "alloca"))
616 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
618 && ! strcmp (name, "__builtin_alloca"))))
619 flags |= ECF_MAY_BE_ALLOCA;
621 /* Disregard prefix _, __ or __x. */
624 if (name[1] == '_' && name[2] == 'x')
626 else if (name[1] == '_')
635 && (! strcmp (tname, "setjmp")
636 || ! strcmp (tname, "setjmp_syscall")))
638 && ! strcmp (tname, "sigsetjmp"))
640 && ! strcmp (tname, "savectx")))
641 flags |= ECF_RETURNS_TWICE;
644 && ! strcmp (tname, "siglongjmp"))
645 flags |= ECF_LONGJMP;
647 else if ((tname[0] == 'q' && tname[1] == 's'
648 && ! strcmp (tname, "qsetjmp"))
649 || (tname[0] == 'v' && tname[1] == 'f'
650 && ! strcmp (tname, "vfork")))
651 flags |= ECF_RETURNS_TWICE;
653 else if (tname[0] == 'l' && tname[1] == 'o'
654 && ! strcmp (tname, "longjmp"))
655 flags |= ECF_LONGJMP;
657 else if ((tname[0] == 'f' && tname[1] == 'o'
658 && ! strcmp (tname, "fork"))
659 /* Linux specific: __clone. check NAME to insist on the
660 leading underscores, to avoid polluting the ISO / POSIX
662 || (name[0] == '_' && name[1] == '_'
663 && ! strcmp (tname, "clone"))
664 || (tname[0] == 'e' && tname[1] == 'x' && tname[2] == 'e'
665 && tname[3] == 'c' && (tname[4] == 'l' || tname[4] == 'v')
667 || ((tname[5] == 'p' || tname[5] == 'e')
668 && tname[6] == '\0'))))
669 flags |= ECF_FORK_OR_EXEC;
674 /* Return nonzero when tree represent call to longjmp. */
677 setjmp_call_p (tree fndecl)
679 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
682 /* Return true when exp contains alloca call. */
684 alloca_call_p (tree exp)
686 if (TREE_CODE (exp) == CALL_EXPR
687 && TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
688 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
690 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
691 0) & ECF_MAY_BE_ALLOCA))
696 /* Detect flags (function attributes) from the function decl or type node. */
699 flags_from_decl_or_type (tree exp)
706 struct cgraph_rtl_info *i = cgraph_rtl_info (exp);
707 type = TREE_TYPE (exp);
711 if (i->pure_function)
712 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
713 if (i->const_function)
714 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
717 /* The function exp may have the `malloc' attribute. */
718 if (DECL_IS_MALLOC (exp))
721 /* The function exp may have the `pure' attribute. */
722 if (DECL_IS_PURE (exp))
723 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
725 if (TREE_NOTHROW (exp))
726 flags |= ECF_NOTHROW;
728 if (TREE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
729 flags |= ECF_LIBCALL_BLOCK | ECF_CONST;
731 else if (TYPE_P (exp) && TYPE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
734 if (TREE_THIS_VOLATILE (exp))
735 flags |= ECF_NORETURN;
737 /* Mark if the function returns with the stack pointer depressed. We
738 cannot consider it pure or constant in that case. */
739 if (TREE_CODE (type) == FUNCTION_TYPE && TYPE_RETURNS_STACK_DEPRESSED (type))
741 flags |= ECF_SP_DEPRESSED;
742 flags &= ~(ECF_PURE | ECF_CONST | ECF_LIBCALL_BLOCK);
748 /* Detect flags from a CALL_EXPR. */
751 call_expr_flags (tree t)
754 tree decl = get_callee_fndecl (t);
757 flags = flags_from_decl_or_type (decl);
760 t = TREE_TYPE (TREE_OPERAND (t, 0));
761 if (t && TREE_CODE (t) == POINTER_TYPE)
762 flags = flags_from_decl_or_type (TREE_TYPE (t));
770 /* Precompute all register parameters as described by ARGS, storing values
771 into fields within the ARGS array.
773 NUM_ACTUALS indicates the total number elements in the ARGS array.
775 Set REG_PARM_SEEN if we encounter a register parameter. */
778 precompute_register_parameters (int num_actuals, struct arg_data *args, int *reg_parm_seen)
784 for (i = 0; i < num_actuals; i++)
785 if (args[i].reg != 0 && ! args[i].pass_on_stack)
789 if (args[i].value == 0)
792 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
794 preserve_temp_slots (args[i].value);
797 /* ANSI doesn't require a sequence point here,
798 but PCC has one, so this will avoid some problems. */
802 /* If the value is a non-legitimate constant, force it into a
803 pseudo now. TLS symbols sometimes need a call to resolve. */
804 if (CONSTANT_P (args[i].value)
805 && !LEGITIMATE_CONSTANT_P (args[i].value))
806 args[i].value = force_reg (args[i].mode, args[i].value);
808 /* If we are to promote the function arg to a wider mode,
811 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
813 = convert_modes (args[i].mode,
814 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
815 args[i].value, args[i].unsignedp);
817 /* If the value is expensive, and we are inside an appropriately
818 short loop, put the value into a pseudo and then put the pseudo
821 For small register classes, also do this if this call uses
822 register parameters. This is to avoid reload conflicts while
823 loading the parameters registers. */
825 if ((! (GET_CODE (args[i].value) == REG
826 || (GET_CODE (args[i].value) == SUBREG
827 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
828 && args[i].mode != BLKmode
829 && rtx_cost (args[i].value, SET) > COSTS_N_INSNS (1)
830 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
831 || preserve_subexpressions_p ()))
832 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
836 #ifdef REG_PARM_STACK_SPACE
838 /* The argument list is the property of the called routine and it
839 may clobber it. If the fixed area has been used for previous
840 parameters, we must save and restore it. */
843 save_fixed_argument_area (int reg_parm_stack_space, rtx argblock, int *low_to_save, int *high_to_save)
848 /* Compute the boundary of the area that needs to be saved, if any. */
849 high = reg_parm_stack_space;
850 #ifdef ARGS_GROW_DOWNWARD
853 if (high > highest_outgoing_arg_in_use)
854 high = highest_outgoing_arg_in_use;
856 for (low = 0; low < high; low++)
857 if (stack_usage_map[low] != 0)
860 enum machine_mode save_mode;
865 while (stack_usage_map[--high] == 0)
869 *high_to_save = high;
871 num_to_save = high - low + 1;
872 save_mode = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
874 /* If we don't have the required alignment, must do this
876 if ((low & (MIN (GET_MODE_SIZE (save_mode),
877 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
880 #ifdef ARGS_GROW_DOWNWARD
885 stack_area = gen_rtx_MEM (save_mode,
886 memory_address (save_mode,
887 plus_constant (argblock,
890 set_mem_align (stack_area, PARM_BOUNDARY);
891 if (save_mode == BLKmode)
893 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
894 emit_block_move (validize_mem (save_area), stack_area,
895 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
899 save_area = gen_reg_rtx (save_mode);
900 emit_move_insn (save_area, stack_area);
910 restore_fixed_argument_area (rtx save_area, rtx argblock, int high_to_save, int low_to_save)
912 enum machine_mode save_mode = GET_MODE (save_area);
916 #ifdef ARGS_GROW_DOWNWARD
917 delta = -high_to_save;
921 stack_area = gen_rtx_MEM (save_mode,
922 memory_address (save_mode,
923 plus_constant (argblock, delta)));
924 set_mem_align (stack_area, PARM_BOUNDARY);
926 if (save_mode != BLKmode)
927 emit_move_insn (stack_area, save_area);
929 emit_block_move (stack_area, validize_mem (save_area),
930 GEN_INT (high_to_save - low_to_save + 1),
933 #endif /* REG_PARM_STACK_SPACE */
935 /* If any elements in ARGS refer to parameters that are to be passed in
936 registers, but not in memory, and whose alignment does not permit a
937 direct copy into registers. Copy the values into a group of pseudos
938 which we will later copy into the appropriate hard registers.
940 Pseudos for each unaligned argument will be stored into the array
941 args[argnum].aligned_regs. The caller is responsible for deallocating
942 the aligned_regs array if it is nonzero. */
945 store_unaligned_arguments_into_pseudos (struct arg_data *args, int num_actuals)
949 for (i = 0; i < num_actuals; i++)
950 if (args[i].reg != 0 && ! args[i].pass_on_stack
951 && args[i].mode == BLKmode
952 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
953 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
955 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
956 int nregs = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
957 int endian_correction = 0;
959 args[i].n_aligned_regs = args[i].partial ? args[i].partial : nregs;
960 args[i].aligned_regs = xmalloc (sizeof (rtx) * args[i].n_aligned_regs);
962 /* Structures smaller than a word are normally aligned to the
963 least significant byte. On a BYTES_BIG_ENDIAN machine,
964 this means we must skip the empty high order bytes when
965 calculating the bit offset. */
966 if (bytes < UNITS_PER_WORD
967 #ifdef BLOCK_REG_PADDING
968 && (BLOCK_REG_PADDING (args[i].mode,
969 TREE_TYPE (args[i].tree_value), 1)
975 endian_correction = BITS_PER_WORD - bytes * BITS_PER_UNIT;
977 for (j = 0; j < args[i].n_aligned_regs; j++)
979 rtx reg = gen_reg_rtx (word_mode);
980 rtx word = operand_subword_force (args[i].value, j, BLKmode);
981 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
983 args[i].aligned_regs[j] = reg;
984 word = extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
985 word_mode, word_mode, BITS_PER_WORD);
987 /* There is no need to restrict this code to loading items
988 in TYPE_ALIGN sized hunks. The bitfield instructions can
989 load up entire word sized registers efficiently.
991 ??? This may not be needed anymore.
992 We use to emit a clobber here but that doesn't let later
993 passes optimize the instructions we emit. By storing 0 into
994 the register later passes know the first AND to zero out the
995 bitfield being set in the register is unnecessary. The store
996 of 0 will be deleted as will at least the first AND. */
998 emit_move_insn (reg, const0_rtx);
1000 bytes -= bitsize / BITS_PER_UNIT;
1001 store_bit_field (reg, bitsize, endian_correction, word_mode,
1002 word, BITS_PER_WORD);
1007 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1010 NUM_ACTUALS is the total number of parameters.
1012 N_NAMED_ARGS is the total number of named arguments.
1014 FNDECL is the tree code for the target of this call (if known)
1016 ARGS_SO_FAR holds state needed by the target to know where to place
1019 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1020 for arguments which are passed in registers.
1022 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1023 and may be modified by this routine.
1025 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1026 flags which may may be modified by this routine.
1028 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1029 the thunked-to function. */
1032 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
1033 struct arg_data *args,
1034 struct args_size *args_size,
1035 int n_named_args ATTRIBUTE_UNUSED,
1036 tree actparms, tree fndecl,
1037 CUMULATIVE_ARGS *args_so_far,
1038 int reg_parm_stack_space,
1039 rtx *old_stack_level, int *old_pending_adj,
1040 int *must_preallocate, int *ecf_flags,
1041 bool call_from_thunk_p)
1043 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1046 /* Count arg position in order args appear. */
1052 args_size->constant = 0;
1055 /* In this loop, we consider args in the order they are written.
1056 We fill up ARGS from the front or from the back if necessary
1057 so that in any case the first arg to be pushed ends up at the front. */
1059 if (PUSH_ARGS_REVERSED)
1061 i = num_actuals - 1, inc = -1;
1062 /* In this case, must reverse order of args
1063 so that we compute and push the last arg first. */
1070 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1071 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1073 tree type = TREE_TYPE (TREE_VALUE (p));
1075 enum machine_mode mode;
1077 args[i].tree_value = TREE_VALUE (p);
1079 /* Replace erroneous argument with constant zero. */
1080 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1081 args[i].tree_value = integer_zero_node, type = integer_type_node;
1083 /* If TYPE is a transparent union, pass things the way we would
1084 pass the first field of the union. We have already verified that
1085 the modes are the same. */
1086 if (TREE_CODE (type) == UNION_TYPE && TYPE_TRANSPARENT_UNION (type))
1087 type = TREE_TYPE (TYPE_FIELDS (type));
1089 /* Decide where to pass this arg.
1091 args[i].reg is nonzero if all or part is passed in registers.
1093 args[i].partial is nonzero if part but not all is passed in registers,
1094 and the exact value says how many words are passed in registers.
1096 args[i].pass_on_stack is nonzero if the argument must at least be
1097 computed on the stack. It may then be loaded back into registers
1098 if args[i].reg is nonzero.
1100 These decisions are driven by the FUNCTION_... macros and must agree
1101 with those made by function.c. */
1103 /* See if this argument should be passed by invisible reference. */
1104 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (type))
1105 || TREE_ADDRESSABLE (type)
1106 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1107 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
1108 type, argpos < n_named_args)
1112 /* If we're compiling a thunk, pass through invisible
1113 references instead of making a copy. */
1114 if (call_from_thunk_p
1115 #ifdef FUNCTION_ARG_CALLEE_COPIES
1116 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
1117 type, argpos < n_named_args)
1118 /* If it's in a register, we must make a copy of it too. */
1119 /* ??? Is this a sufficient test? Is there a better one? */
1120 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1121 && REG_P (DECL_RTL (args[i].tree_value)))
1122 && ! TREE_ADDRESSABLE (type))
1126 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1127 new object from the argument. If we are passing by
1128 invisible reference, the callee will do that for us, so we
1129 can strip off the TARGET_EXPR. This is not always safe,
1130 but it is safe in the only case where this is a useful
1131 optimization; namely, when the argument is a plain object.
1132 In that case, the frontend is just asking the backend to
1133 make a bitwise copy of the argument. */
1135 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
1136 && (DECL_P (TREE_OPERAND (args[i].tree_value, 1)))
1137 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
1138 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
1140 args[i].tree_value = build1 (ADDR_EXPR,
1141 build_pointer_type (type),
1142 args[i].tree_value);
1143 type = build_pointer_type (type);
1145 else if (TREE_CODE (args[i].tree_value) == TARGET_EXPR)
1147 /* In the V3 C++ ABI, parameters are destroyed in the caller.
1148 We implement this by passing the address of the temporary
1149 rather than expanding it into another allocated slot. */
1150 args[i].tree_value = build1 (ADDR_EXPR,
1151 build_pointer_type (type),
1152 args[i].tree_value);
1153 type = build_pointer_type (type);
1157 /* We make a copy of the object and pass the address to the
1158 function being called. */
1161 if (!COMPLETE_TYPE_P (type)
1162 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1163 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1164 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1165 STACK_CHECK_MAX_VAR_SIZE))))
1167 /* This is a variable-sized object. Make space on the stack
1169 rtx size_rtx = expr_size (TREE_VALUE (p));
1171 if (*old_stack_level == 0)
1173 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1174 *old_pending_adj = pending_stack_adjust;
1175 pending_stack_adjust = 0;
1178 copy = gen_rtx_MEM (BLKmode,
1179 allocate_dynamic_stack_space
1180 (size_rtx, NULL_RTX, TYPE_ALIGN (type)));
1181 set_mem_attributes (copy, type, 1);
1184 copy = assign_temp (type, 0, 1, 0);
1186 store_expr (args[i].tree_value, copy, 0);
1187 *ecf_flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
1189 args[i].tree_value = build1 (ADDR_EXPR,
1190 build_pointer_type (type),
1191 make_tree (type, copy));
1192 type = build_pointer_type (type);
1196 mode = TYPE_MODE (type);
1197 unsignedp = TYPE_UNSIGNED (type);
1199 if (targetm.calls.promote_function_args (fndecl ? TREE_TYPE (fndecl) : 0))
1200 mode = promote_mode (type, mode, &unsignedp, 1);
1202 args[i].unsignedp = unsignedp;
1203 args[i].mode = mode;
1205 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1206 argpos < n_named_args);
1207 #ifdef FUNCTION_INCOMING_ARG
1208 /* If this is a sibling call and the machine has register windows, the
1209 register window has to be unwinded before calling the routine, so
1210 arguments have to go into the incoming registers. */
1211 args[i].tail_call_reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1212 argpos < n_named_args);
1214 args[i].tail_call_reg = args[i].reg;
1217 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1220 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1221 argpos < n_named_args);
1224 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1226 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1227 it means that we are to pass this arg in the register(s) designated
1228 by the PARALLEL, but also to pass it in the stack. */
1229 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1230 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1231 args[i].pass_on_stack = 1;
1233 /* If this is an addressable type, we must preallocate the stack
1234 since we must evaluate the object into its final location.
1236 If this is to be passed in both registers and the stack, it is simpler
1238 if (TREE_ADDRESSABLE (type)
1239 || (args[i].pass_on_stack && args[i].reg != 0))
1240 *must_preallocate = 1;
1242 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1243 we cannot consider this function call constant. */
1244 if (TREE_ADDRESSABLE (type))
1245 *ecf_flags &= ~ECF_LIBCALL_BLOCK;
1247 /* Compute the stack-size of this argument. */
1248 if (args[i].reg == 0 || args[i].partial != 0
1249 || reg_parm_stack_space > 0
1250 || args[i].pass_on_stack)
1251 locate_and_pad_parm (mode, type,
1252 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1257 args[i].pass_on_stack ? 0 : args[i].partial,
1258 fndecl, args_size, &args[i].locate);
1259 #ifdef BLOCK_REG_PADDING
1261 /* The argument is passed entirely in registers. See at which
1262 end it should be padded. */
1263 args[i].locate.where_pad =
1264 BLOCK_REG_PADDING (mode, type,
1265 int_size_in_bytes (type) <= UNITS_PER_WORD);
1268 /* Update ARGS_SIZE, the total stack space for args so far. */
1270 args_size->constant += args[i].locate.size.constant;
1271 if (args[i].locate.size.var)
1272 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
1274 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1275 have been used, etc. */
1277 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1278 argpos < n_named_args);
1282 /* Update ARGS_SIZE to contain the total size for the argument block.
1283 Return the original constant component of the argument block's size.
1285 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1286 for arguments passed in registers. */
1289 compute_argument_block_size (int reg_parm_stack_space,
1290 struct args_size *args_size,
1291 int preferred_stack_boundary ATTRIBUTE_UNUSED)
1293 int unadjusted_args_size = args_size->constant;
1295 /* For accumulate outgoing args mode we don't need to align, since the frame
1296 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1297 backends from generating misaligned frame sizes. */
1298 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1299 preferred_stack_boundary = STACK_BOUNDARY;
1301 /* Compute the actual size of the argument block required. The variable
1302 and constant sizes must be combined, the size may have to be rounded,
1303 and there may be a minimum required size. */
1307 args_size->var = ARGS_SIZE_TREE (*args_size);
1308 args_size->constant = 0;
1310 preferred_stack_boundary /= BITS_PER_UNIT;
1311 if (preferred_stack_boundary > 1)
1313 /* We don't handle this case yet. To handle it correctly we have
1314 to add the delta, round and subtract the delta.
1315 Currently no machine description requires this support. */
1316 if (stack_pointer_delta & (preferred_stack_boundary - 1))
1318 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1321 if (reg_parm_stack_space > 0)
1324 = size_binop (MAX_EXPR, args_size->var,
1325 ssize_int (reg_parm_stack_space));
1327 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1328 /* The area corresponding to register parameters is not to count in
1329 the size of the block we need. So make the adjustment. */
1331 = size_binop (MINUS_EXPR, args_size->var,
1332 ssize_int (reg_parm_stack_space));
1338 preferred_stack_boundary /= BITS_PER_UNIT;
1339 if (preferred_stack_boundary < 1)
1340 preferred_stack_boundary = 1;
1341 args_size->constant = (((args_size->constant
1342 + stack_pointer_delta
1343 + preferred_stack_boundary - 1)
1344 / preferred_stack_boundary
1345 * preferred_stack_boundary)
1346 - stack_pointer_delta);
1348 args_size->constant = MAX (args_size->constant,
1349 reg_parm_stack_space);
1351 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1352 args_size->constant -= reg_parm_stack_space;
1355 return unadjusted_args_size;
1358 /* Precompute parameters as needed for a function call.
1360 FLAGS is mask of ECF_* constants.
1362 NUM_ACTUALS is the number of arguments.
1364 ARGS is an array containing information for each argument; this
1365 routine fills in the INITIAL_VALUE and VALUE fields for each
1366 precomputed argument. */
1369 precompute_arguments (int flags, int num_actuals, struct arg_data *args)
1373 /* If this is a libcall, then precompute all arguments so that we do not
1374 get extraneous instructions emitted as part of the libcall sequence.
1376 If this target defines ACCUMULATE_OUTGOING_ARGS to true, then we must
1377 precompute all arguments that contain function calls. Otherwise,
1378 computing arguments for a subcall may clobber arguments for this call.
1380 If this target defines ACCUMULATE_OUTGOING_ARGS to false, then we only
1381 need to precompute arguments that change the stack pointer, such as calls
1382 to alloca, and calls that do not pop all of their arguments. */
1384 for (i = 0; i < num_actuals; i++)
1385 if ((flags & ECF_LIBCALL_BLOCK)
1386 || calls_function (args[i].tree_value, !ACCUMULATE_OUTGOING_ARGS))
1388 enum machine_mode mode;
1390 /* If this is an addressable type, we cannot pre-evaluate it. */
1391 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1395 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1397 /* ANSI doesn't require a sequence point here,
1398 but PCC has one, so this will avoid some problems. */
1401 args[i].initial_value = args[i].value
1402 = protect_from_queue (args[i].value, 0);
1404 mode = TYPE_MODE (TREE_TYPE (args[i].tree_value));
1405 if (mode != args[i].mode)
1408 = convert_modes (args[i].mode, mode,
1409 args[i].value, args[i].unsignedp);
1410 #ifdef PROMOTE_FOR_CALL_ONLY
1411 /* CSE will replace this only if it contains args[i].value
1412 pseudo, so convert it down to the declared mode using
1414 if (GET_CODE (args[i].value) == REG
1415 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1417 args[i].initial_value
1418 = gen_lowpart_SUBREG (mode, args[i].value);
1419 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1420 SUBREG_PROMOTED_UNSIGNED_SET (args[i].initial_value,
1428 /* Given the current state of MUST_PREALLOCATE and information about
1429 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1430 compute and return the final value for MUST_PREALLOCATE. */
1433 finalize_must_preallocate (int must_preallocate, int num_actuals, struct arg_data *args, struct args_size *args_size)
1435 /* See if we have or want to preallocate stack space.
1437 If we would have to push a partially-in-regs parm
1438 before other stack parms, preallocate stack space instead.
1440 If the size of some parm is not a multiple of the required stack
1441 alignment, we must preallocate.
1443 If the total size of arguments that would otherwise create a copy in
1444 a temporary (such as a CALL) is more than half the total argument list
1445 size, preallocation is faster.
1447 Another reason to preallocate is if we have a machine (like the m88k)
1448 where stack alignment is required to be maintained between every
1449 pair of insns, not just when the call is made. However, we assume here
1450 that such machines either do not have push insns (and hence preallocation
1451 would occur anyway) or the problem is taken care of with
1454 if (! must_preallocate)
1456 int partial_seen = 0;
1457 int copy_to_evaluate_size = 0;
1460 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1462 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1464 else if (partial_seen && args[i].reg == 0)
1465 must_preallocate = 1;
1467 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1468 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1469 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1470 || TREE_CODE (args[i].tree_value) == COND_EXPR
1471 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1472 copy_to_evaluate_size
1473 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1476 if (copy_to_evaluate_size * 2 >= args_size->constant
1477 && args_size->constant > 0)
1478 must_preallocate = 1;
1480 return must_preallocate;
1483 /* If we preallocated stack space, compute the address of each argument
1484 and store it into the ARGS array.
1486 We need not ensure it is a valid memory address here; it will be
1487 validized when it is used.
1489 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1492 compute_argument_addresses (struct arg_data *args, rtx argblock, int num_actuals)
1496 rtx arg_reg = argblock;
1497 int i, arg_offset = 0;
1499 if (GET_CODE (argblock) == PLUS)
1500 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1502 for (i = 0; i < num_actuals; i++)
1504 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
1505 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
1508 /* Skip this parm if it will not be passed on the stack. */
1509 if (! args[i].pass_on_stack && args[i].reg != 0)
1512 if (GET_CODE (offset) == CONST_INT)
1513 addr = plus_constant (arg_reg, INTVAL (offset));
1515 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1517 addr = plus_constant (addr, arg_offset);
1518 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1519 set_mem_align (args[i].stack, PARM_BOUNDARY);
1520 set_mem_attributes (args[i].stack,
1521 TREE_TYPE (args[i].tree_value), 1);
1523 if (GET_CODE (slot_offset) == CONST_INT)
1524 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1526 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1528 addr = plus_constant (addr, arg_offset);
1529 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1530 set_mem_align (args[i].stack_slot, PARM_BOUNDARY);
1531 set_mem_attributes (args[i].stack_slot,
1532 TREE_TYPE (args[i].tree_value), 1);
1534 /* Function incoming arguments may overlap with sibling call
1535 outgoing arguments and we cannot allow reordering of reads
1536 from function arguments with stores to outgoing arguments
1537 of sibling calls. */
1538 set_mem_alias_set (args[i].stack, 0);
1539 set_mem_alias_set (args[i].stack_slot, 0);
1544 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1545 in a call instruction.
1547 FNDECL is the tree node for the target function. For an indirect call
1548 FNDECL will be NULL_TREE.
1550 ADDR is the operand 0 of CALL_EXPR for this call. */
1553 rtx_for_function_call (tree fndecl, tree addr)
1557 /* Get the function to call, in the form of RTL. */
1560 /* If this is the first use of the function, see if we need to
1561 make an external definition for it. */
1562 if (! TREE_USED (fndecl))
1564 assemble_external (fndecl);
1565 TREE_USED (fndecl) = 1;
1568 /* Get a SYMBOL_REF rtx for the function address. */
1569 funexp = XEXP (DECL_RTL (fndecl), 0);
1572 /* Generate an rtx (probably a pseudo-register) for the address. */
1575 funexp = expand_expr (addr, NULL_RTX, VOIDmode, 0);
1576 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1582 /* Do the register loads required for any wholly-register parms or any
1583 parms which are passed both on the stack and in a register. Their
1584 expressions were already evaluated.
1586 Mark all register-parms as living through the call, putting these USE
1587 insns in the CALL_INSN_FUNCTION_USAGE field.
1589 When IS_SIBCALL, perform the check_sibcall_overlap_argument_overlap
1590 checking, setting *SIBCALL_FAILURE if appropriate. */
1593 load_register_parameters (struct arg_data *args, int num_actuals,
1594 rtx *call_fusage, int flags, int is_sibcall,
1595 int *sibcall_failure)
1599 for (i = 0; i < num_actuals; i++)
1601 rtx reg = ((flags & ECF_SIBCALL)
1602 ? args[i].tail_call_reg : args[i].reg);
1605 int partial = args[i].partial;
1608 rtx before_arg = get_last_insn ();
1609 /* Set to non-negative if must move a word at a time, even if just
1610 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1611 we just use a normal move insn. This value can be zero if the
1612 argument is a zero size structure with no fields. */
1616 else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
1618 size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1619 nregs = (size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1622 size = GET_MODE_SIZE (args[i].mode);
1624 /* Handle calls that pass values in multiple non-contiguous
1625 locations. The Irix 6 ABI has examples of this. */
1627 if (GET_CODE (reg) == PARALLEL)
1629 tree type = TREE_TYPE (args[i].tree_value);
1630 emit_group_load (reg, args[i].value, type,
1631 int_size_in_bytes (type));
1634 /* If simple case, just do move. If normal partial, store_one_arg
1635 has already loaded the register for us. In all other cases,
1636 load the register(s) from memory. */
1638 else if (nregs == -1)
1640 emit_move_insn (reg, args[i].value);
1641 #ifdef BLOCK_REG_PADDING
1642 /* Handle case where we have a value that needs shifting
1643 up to the msb. eg. a QImode value and we're padding
1644 upward on a BYTES_BIG_ENDIAN machine. */
1645 if (size < UNITS_PER_WORD
1646 && (args[i].locate.where_pad
1647 == (BYTES_BIG_ENDIAN ? upward : downward)))
1650 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
1652 /* Assigning REG here rather than a temp makes CALL_FUSAGE
1653 report the whole reg as used. Strictly speaking, the
1654 call only uses SIZE bytes at the msb end, but it doesn't
1655 seem worth generating rtl to say that. */
1656 reg = gen_rtx_REG (word_mode, REGNO (reg));
1657 x = expand_binop (word_mode, ashl_optab, reg,
1658 GEN_INT (shift), reg, 1, OPTAB_WIDEN);
1660 emit_move_insn (reg, x);
1665 /* If we have pre-computed the values to put in the registers in
1666 the case of non-aligned structures, copy them in now. */
1668 else if (args[i].n_aligned_regs != 0)
1669 for (j = 0; j < args[i].n_aligned_regs; j++)
1670 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1671 args[i].aligned_regs[j]);
1673 else if (partial == 0 || args[i].pass_on_stack)
1675 rtx mem = validize_mem (args[i].value);
1677 /* Handle a BLKmode that needs shifting. */
1678 if (nregs == 1 && size < UNITS_PER_WORD
1679 #ifdef BLOCK_REG_PADDING
1680 && args[i].locate.where_pad == downward
1686 rtx tem = operand_subword_force (mem, 0, args[i].mode);
1687 rtx ri = gen_rtx_REG (word_mode, REGNO (reg));
1688 rtx x = gen_reg_rtx (word_mode);
1689 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
1690 optab dir = BYTES_BIG_ENDIAN ? lshr_optab : ashl_optab;
1692 emit_move_insn (x, tem);
1693 x = expand_binop (word_mode, dir, x, GEN_INT (shift),
1694 ri, 1, OPTAB_WIDEN);
1696 emit_move_insn (ri, x);
1699 move_block_to_reg (REGNO (reg), mem, nregs, args[i].mode);
1702 /* When a parameter is a block, and perhaps in other cases, it is
1703 possible that it did a load from an argument slot that was
1704 already clobbered. */
1706 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
1707 *sibcall_failure = 1;
1709 /* Handle calls that pass values in multiple non-contiguous
1710 locations. The Irix 6 ABI has examples of this. */
1711 if (GET_CODE (reg) == PARALLEL)
1712 use_group_regs (call_fusage, reg);
1713 else if (nregs == -1)
1714 use_reg (call_fusage, reg);
1716 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1721 /* Try to integrate function. See expand_inline_function for documentation
1722 about the parameters. */
1725 try_to_integrate (tree fndecl, tree actparms, rtx target, int ignore,
1726 tree type, rtx structure_value_addr)
1731 rtx old_stack_level = 0;
1732 int reg_parm_stack_space = 0;
1734 #ifdef REG_PARM_STACK_SPACE
1735 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1738 before_call = get_last_insn ();
1740 timevar_push (TV_INTEGRATION);
1742 temp = expand_inline_function (fndecl, actparms, target,
1744 structure_value_addr);
1746 timevar_pop (TV_INTEGRATION);
1748 /* If inlining succeeded, return. */
1749 if (temp != (rtx) (size_t) - 1)
1751 if (ACCUMULATE_OUTGOING_ARGS)
1753 /* If the outgoing argument list must be preserved, push
1754 the stack before executing the inlined function if it
1757 i = reg_parm_stack_space;
1758 if (i > highest_outgoing_arg_in_use)
1759 i = highest_outgoing_arg_in_use;
1760 while (--i >= 0 && stack_usage_map[i] == 0)
1763 if (stack_arg_under_construction || i >= 0)
1766 = before_call ? NEXT_INSN (before_call) : get_insns ();
1767 rtx insn = NULL_RTX, seq;
1769 /* Look for a call in the inline function code.
1770 If DECL_STRUCT_FUNCTION (fndecl)->outgoing_args_size is
1771 nonzero then there is a call and it is not necessary
1772 to scan the insns. */
1774 if (DECL_STRUCT_FUNCTION (fndecl)->outgoing_args_size == 0)
1775 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1776 if (GET_CODE (insn) == CALL_INSN)
1781 /* Reserve enough stack space so that the largest
1782 argument list of any function call in the inline
1783 function does not overlap the argument list being
1784 evaluated. This is usually an overestimate because
1785 allocate_dynamic_stack_space reserves space for an
1786 outgoing argument list in addition to the requested
1787 space, but there is no way to ask for stack space such
1788 that an argument list of a certain length can be
1791 Add the stack space reserved for register arguments, if
1792 any, in the inline function. What is really needed is the
1793 largest value of reg_parm_stack_space in the inline
1794 function, but that is not available. Using the current
1795 value of reg_parm_stack_space is wrong, but gives
1796 correct results on all supported machines. */
1799 (DECL_STRUCT_FUNCTION (fndecl)->outgoing_args_size
1800 + reg_parm_stack_space);
1803 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1804 allocate_dynamic_stack_space (GEN_INT (adjust),
1805 NULL_RTX, BITS_PER_UNIT);
1808 emit_insn_before (seq, first_insn);
1809 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1814 /* If the result is equivalent to TARGET, return TARGET to simplify
1815 checks in store_expr. They can be equivalent but not equal in the
1816 case of a function that returns BLKmode. */
1817 if (temp != target && rtx_equal_p (temp, target))
1822 /* If inlining failed, mark FNDECL as needing to be compiled
1823 separately after all. If function was declared inline,
1825 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1826 && optimize > 0 && !TREE_ADDRESSABLE (fndecl))
1828 warning ("%Jinlining failed in call to '%F'", fndecl, fndecl);
1829 warning ("called from here");
1831 lang_hooks.mark_addressable (fndecl);
1832 return (rtx) (size_t) - 1;
1835 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1836 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1837 bytes, then we would need to push some additional bytes to pad the
1838 arguments. So, we compute an adjust to the stack pointer for an
1839 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1840 bytes. Then, when the arguments are pushed the stack will be perfectly
1841 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1842 be popped after the call. Returns the adjustment. */
1845 combine_pending_stack_adjustment_and_call (int unadjusted_args_size,
1846 struct args_size *args_size,
1847 int preferred_unit_stack_boundary)
1849 /* The number of bytes to pop so that the stack will be
1850 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1851 HOST_WIDE_INT adjustment;
1852 /* The alignment of the stack after the arguments are pushed, if we
1853 just pushed the arguments without adjust the stack here. */
1854 HOST_WIDE_INT unadjusted_alignment;
1856 unadjusted_alignment
1857 = ((stack_pointer_delta + unadjusted_args_size)
1858 % preferred_unit_stack_boundary);
1860 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1861 as possible -- leaving just enough left to cancel out the
1862 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1863 PENDING_STACK_ADJUST is non-negative, and congruent to
1864 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1866 /* Begin by trying to pop all the bytes. */
1867 unadjusted_alignment
1868 = (unadjusted_alignment
1869 - (pending_stack_adjust % preferred_unit_stack_boundary));
1870 adjustment = pending_stack_adjust;
1871 /* Push enough additional bytes that the stack will be aligned
1872 after the arguments are pushed. */
1873 if (preferred_unit_stack_boundary > 1)
1875 if (unadjusted_alignment > 0)
1876 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1878 adjustment += unadjusted_alignment;
1881 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1882 bytes after the call. The right number is the entire
1883 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1884 by the arguments in the first place. */
1886 = pending_stack_adjust - adjustment + unadjusted_args_size;
1891 /* Scan X expression if it does not dereference any argument slots
1892 we already clobbered by tail call arguments (as noted in stored_args_map
1894 Return nonzero if X expression dereferences such argument slots,
1898 check_sibcall_argument_overlap_1 (rtx x)
1908 code = GET_CODE (x);
1912 if (XEXP (x, 0) == current_function_internal_arg_pointer)
1914 else if (GET_CODE (XEXP (x, 0)) == PLUS
1915 && XEXP (XEXP (x, 0), 0) ==
1916 current_function_internal_arg_pointer
1917 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
1918 i = INTVAL (XEXP (XEXP (x, 0), 1));
1922 #ifdef ARGS_GROW_DOWNWARD
1923 i = -i - GET_MODE_SIZE (GET_MODE (x));
1926 for (k = 0; k < GET_MODE_SIZE (GET_MODE (x)); k++)
1927 if (i + k < stored_args_map->n_bits
1928 && TEST_BIT (stored_args_map, i + k))
1934 /* Scan all subexpressions. */
1935 fmt = GET_RTX_FORMAT (code);
1936 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
1940 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
1943 else if (*fmt == 'E')
1945 for (j = 0; j < XVECLEN (x, i); j++)
1946 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
1953 /* Scan sequence after INSN if it does not dereference any argument slots
1954 we already clobbered by tail call arguments (as noted in stored_args_map
1955 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
1956 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
1957 should be 0). Return nonzero if sequence after INSN dereferences such argument
1958 slots, zero otherwise. */
1961 check_sibcall_argument_overlap (rtx insn, struct arg_data *arg, int mark_stored_args_map)
1965 if (insn == NULL_RTX)
1966 insn = get_insns ();
1968 insn = NEXT_INSN (insn);
1970 for (; insn; insn = NEXT_INSN (insn))
1972 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
1975 if (mark_stored_args_map)
1977 #ifdef ARGS_GROW_DOWNWARD
1978 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
1980 low = arg->locate.slot_offset.constant;
1983 for (high = low + arg->locate.size.constant; low < high; low++)
1984 SET_BIT (stored_args_map, low);
1986 return insn != NULL_RTX;
1990 fix_unsafe_tree (tree t)
1992 switch (unsafe_for_reeval (t))
1997 case 1: /* Mildly unsafe. */
1998 t = unsave_expr (t);
2001 case 2: /* Wildly unsafe. */
2003 tree var = build_decl (VAR_DECL, NULL_TREE,
2006 expand_expr (t, NULL_RTX, VOIDmode, EXPAND_NORMAL));
2018 /* If function value *VALUE was returned at the most significant end of a
2019 register, shift it towards the least significant end and convert it to
2020 TYPE's mode. Return true and update *VALUE if some action was needed.
2022 TYPE is the type of the function's return value, which is known not
2023 to have mode BLKmode. */
2026 shift_returned_value (tree type, rtx *value)
2028 if (targetm.calls.return_in_msb (type))
2030 HOST_WIDE_INT shift;
2032 shift = (GET_MODE_BITSIZE (GET_MODE (*value))
2033 - BITS_PER_UNIT * int_size_in_bytes (type));
2036 *value = expand_binop (GET_MODE (*value), lshr_optab, *value,
2037 GEN_INT (shift), 0, 1, OPTAB_WIDEN);
2038 *value = convert_to_mode (TYPE_MODE (type), *value, 0);
2045 /* Generate all the code for a function call
2046 and return an rtx for its value.
2047 Store the value in TARGET (specified as an rtx) if convenient.
2048 If the value is stored in TARGET then TARGET is returned.
2049 If IGNORE is nonzero, then we ignore the value of the function call. */
2052 expand_call (tree exp, rtx target, int ignore)
2054 /* Nonzero if we are currently expanding a call. */
2055 static int currently_expanding_call = 0;
2057 /* List of actual parameters. */
2058 tree actparms = TREE_OPERAND (exp, 1);
2059 /* RTX for the function to be called. */
2061 /* Sequence of insns to perform a tail recursive "call". */
2062 rtx tail_recursion_insns = NULL_RTX;
2063 /* Sequence of insns to perform a normal "call". */
2064 rtx normal_call_insns = NULL_RTX;
2065 /* Sequence of insns to perform a tail recursive "call". */
2066 rtx tail_call_insns = NULL_RTX;
2067 /* Data type of the function. */
2069 tree type_arg_types;
2070 /* Declaration of the function being called,
2071 or 0 if the function is computed (not known by name). */
2073 /* The type of the function being called. */
2076 int try_tail_call = 1;
2077 int try_tail_recursion = 1;
2080 /* Register in which non-BLKmode value will be returned,
2081 or 0 if no value or if value is BLKmode. */
2083 /* Address where we should return a BLKmode value;
2084 0 if value not BLKmode. */
2085 rtx structure_value_addr = 0;
2086 /* Nonzero if that address is being passed by treating it as
2087 an extra, implicit first parameter. Otherwise,
2088 it is passed by being copied directly into struct_value_rtx. */
2089 int structure_value_addr_parm = 0;
2090 /* Size of aggregate value wanted, or zero if none wanted
2091 or if we are using the non-reentrant PCC calling convention
2092 or expecting the value in registers. */
2093 HOST_WIDE_INT struct_value_size = 0;
2094 /* Nonzero if called function returns an aggregate in memory PCC style,
2095 by returning the address of where to find it. */
2096 int pcc_struct_value = 0;
2097 rtx struct_value = 0;
2099 /* Number of actual parameters in this call, including struct value addr. */
2101 /* Number of named args. Args after this are anonymous ones
2102 and they must all go on the stack. */
2105 /* Vector of information about each argument.
2106 Arguments are numbered in the order they will be pushed,
2107 not the order they are written. */
2108 struct arg_data *args;
2110 /* Total size in bytes of all the stack-parms scanned so far. */
2111 struct args_size args_size;
2112 struct args_size adjusted_args_size;
2113 /* Size of arguments before any adjustments (such as rounding). */
2114 int unadjusted_args_size;
2115 /* Data on reg parms scanned so far. */
2116 CUMULATIVE_ARGS args_so_far;
2117 /* Nonzero if a reg parm has been scanned. */
2119 /* Nonzero if this is an indirect function call. */
2121 /* Nonzero if we must avoid push-insns in the args for this call.
2122 If stack space is allocated for register parameters, but not by the
2123 caller, then it is preallocated in the fixed part of the stack frame.
2124 So the entire argument block must then be preallocated (i.e., we
2125 ignore PUSH_ROUNDING in that case). */
2127 int must_preallocate = !PUSH_ARGS;
2129 /* Size of the stack reserved for parameter registers. */
2130 int reg_parm_stack_space = 0;
2132 /* Address of space preallocated for stack parms
2133 (on machines that lack push insns), or 0 if space not preallocated. */
2136 /* Mask of ECF_ flags. */
2138 /* Nonzero if this is a call to an inline function. */
2139 int is_integrable = 0;
2140 #ifdef REG_PARM_STACK_SPACE
2141 /* Define the boundary of the register parm stack space that needs to be
2143 int low_to_save, high_to_save;
2144 rtx save_area = 0; /* Place that it is saved */
2147 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2148 rtx temp_target = 0;
2149 char *initial_stack_usage_map = stack_usage_map;
2151 int old_stack_allocated;
2153 /* State variables to track stack modifications. */
2154 rtx old_stack_level = 0;
2155 int old_stack_arg_under_construction = 0;
2156 int old_pending_adj = 0;
2157 int old_inhibit_defer_pop = inhibit_defer_pop;
2159 /* Some stack pointer alterations we make are performed via
2160 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
2161 which we then also need to save/restore along the way. */
2162 int old_stack_pointer_delta = 0;
2165 tree p = TREE_OPERAND (exp, 0);
2166 tree addr = TREE_OPERAND (exp, 0);
2168 /* The alignment of the stack, in bits. */
2169 HOST_WIDE_INT preferred_stack_boundary;
2170 /* The alignment of the stack, in bytes. */
2171 HOST_WIDE_INT preferred_unit_stack_boundary;
2173 /* See if this is "nothrow" function call. */
2174 if (TREE_NOTHROW (exp))
2175 flags |= ECF_NOTHROW;
2177 /* See if we can find a DECL-node for the actual function.
2178 As a result, decide whether this is a call to an integrable function. */
2180 fndecl = get_callee_fndecl (exp);
2183 fntype = TREE_TYPE (fndecl);
2185 && fndecl != current_function_decl
2186 && DECL_INLINE (fndecl)
2187 && DECL_STRUCT_FUNCTION (fndecl)
2188 && DECL_STRUCT_FUNCTION (fndecl)->inlinable)
2190 else if (! TREE_ADDRESSABLE (fndecl))
2192 /* In case this function later becomes inlinable,
2193 record that there was already a non-inline call to it.
2195 Use abstraction instead of setting TREE_ADDRESSABLE
2197 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2200 warning ("%Jcan't inline call to '%F'", fndecl, fndecl);
2201 warning ("called from here");
2203 lang_hooks.mark_addressable (fndecl);
2207 && lookup_attribute ("warn_unused_result",
2208 TYPE_ATTRIBUTES (TREE_TYPE (fndecl))))
2209 warning ("ignoring return value of `%D', "
2210 "declared with attribute warn_unused_result", fndecl);
2212 flags |= flags_from_decl_or_type (fndecl);
2215 /* If we don't have specific function to call, see if we have a
2216 attributes set in the type. */
2219 fntype = TREE_TYPE (TREE_TYPE (p));
2221 && lookup_attribute ("warn_unused_result", TYPE_ATTRIBUTES (fntype)))
2222 warning ("ignoring return value of function "
2223 "declared with attribute warn_unused_result");
2224 flags |= flags_from_decl_or_type (fntype);
2227 struct_value = targetm.calls.struct_value_rtx (fntype, 0);
2229 /* Warn if this value is an aggregate type,
2230 regardless of which calling convention we are using for it. */
2231 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2232 warning ("function call has aggregate value");
2234 /* If the result of a pure or const function call is ignored (or void),
2235 and none of its arguments are volatile, we can avoid expanding the
2236 call and just evaluate the arguments for side-effects. */
2237 if ((flags & (ECF_CONST | ECF_PURE))
2238 && (ignore || target == const0_rtx
2239 || TYPE_MODE (TREE_TYPE (exp)) == VOIDmode))
2241 bool volatilep = false;
2244 for (arg = actparms; arg; arg = TREE_CHAIN (arg))
2245 if (TREE_THIS_VOLATILE (TREE_VALUE (arg)))
2253 for (arg = actparms; arg; arg = TREE_CHAIN (arg))
2254 expand_expr (TREE_VALUE (arg), const0_rtx,
2255 VOIDmode, EXPAND_NORMAL);
2260 #ifdef REG_PARM_STACK_SPACE
2261 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2264 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2265 if (reg_parm_stack_space > 0 && PUSH_ARGS)
2266 must_preallocate = 1;
2269 /* Set up a place to return a structure. */
2271 /* Cater to broken compilers. */
2272 if (aggregate_value_p (exp, fndecl))
2274 /* This call returns a big structure. */
2275 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
2277 #ifdef PCC_STATIC_STRUCT_RETURN
2279 pcc_struct_value = 1;
2280 /* Easier than making that case work right. */
2283 /* In case this is a static function, note that it has been
2285 if (! TREE_ADDRESSABLE (fndecl))
2286 lang_hooks.mark_addressable (fndecl);
2290 #else /* not PCC_STATIC_STRUCT_RETURN */
2292 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2294 if (CALL_EXPR_HAS_RETURN_SLOT_ADDR (exp))
2296 /* The structure value address arg is already in actparms.
2297 Pull it out. It might be nice to just leave it there, but
2298 we need to set structure_value_addr. */
2299 tree return_arg = TREE_VALUE (actparms);
2300 actparms = TREE_CHAIN (actparms);
2301 structure_value_addr = expand_expr (return_arg, NULL_RTX,
2302 VOIDmode, EXPAND_NORMAL);
2304 else if (target && GET_CODE (target) == MEM)
2305 structure_value_addr = XEXP (target, 0);
2308 /* For variable-sized objects, we must be called with a target
2309 specified. If we were to allocate space on the stack here,
2310 we would have no way of knowing when to free it. */
2311 rtx d = assign_temp (TREE_TYPE (exp), 1, 1, 1);
2313 mark_temp_addr_taken (d);
2314 structure_value_addr = XEXP (d, 0);
2318 #endif /* not PCC_STATIC_STRUCT_RETURN */
2321 /* If called function is inline, try to integrate it. */
2325 rtx temp = try_to_integrate (fndecl, actparms, target,
2326 ignore, TREE_TYPE (exp),
2327 structure_value_addr);
2328 if (temp != (rtx) (size_t) - 1)
2332 /* Figure out the amount to which the stack should be aligned. */
2333 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2336 struct cgraph_rtl_info *i = cgraph_rtl_info (fndecl);
2337 if (i && i->preferred_incoming_stack_boundary)
2338 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
2341 /* Operand 0 is a pointer-to-function; get the type of the function. */
2342 funtype = TREE_TYPE (addr);
2343 if (! POINTER_TYPE_P (funtype))
2345 funtype = TREE_TYPE (funtype);
2347 /* Munge the tree to split complex arguments into their imaginary
2349 if (targetm.calls.split_complex_arg)
2351 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
2352 actparms = split_complex_values (actparms);
2355 type_arg_types = TYPE_ARG_TYPES (funtype);
2357 /* See if this is a call to a function that can return more than once
2358 or a call to longjmp or malloc. */
2359 flags |= special_function_p (fndecl, flags);
2361 if (flags & ECF_MAY_BE_ALLOCA)
2362 current_function_calls_alloca = 1;
2364 /* If struct_value_rtx is 0, it means pass the address
2365 as if it were an extra parameter. */
2366 if (structure_value_addr && struct_value == 0)
2368 /* If structure_value_addr is a REG other than
2369 virtual_outgoing_args_rtx, we can use always use it. If it
2370 is not a REG, we must always copy it into a register.
2371 If it is virtual_outgoing_args_rtx, we must copy it to another
2372 register in some cases. */
2373 rtx temp = (GET_CODE (structure_value_addr) != REG
2374 || (ACCUMULATE_OUTGOING_ARGS
2375 && stack_arg_under_construction
2376 && structure_value_addr == virtual_outgoing_args_rtx)
2377 ? copy_addr_to_reg (convert_memory_address
2378 (Pmode, structure_value_addr))
2379 : structure_value_addr);
2382 = tree_cons (error_mark_node,
2383 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2386 structure_value_addr_parm = 1;
2389 /* Count the arguments and set NUM_ACTUALS. */
2390 for (p = actparms, num_actuals = 0; p; p = TREE_CHAIN (p))
2393 /* Compute number of named args.
2394 Normally, don't include the last named arg if anonymous args follow.
2395 We do include the last named arg if
2396 targetm.calls.strict_argument_naming() returns nonzero.
2397 (If no anonymous args follow, the result of list_length is actually
2398 one too large. This is harmless.)
2400 If targetm.calls.pretend_outgoing_varargs_named() returns
2401 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2402 this machine will be able to place unnamed args that were passed
2403 in registers into the stack. So treat all args as named. This
2404 allows the insns emitting for a specific argument list to be
2405 independent of the function declaration.
2407 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2408 we do not have any reliable way to pass unnamed args in
2409 registers, so we must force them into memory. */
2411 if ((targetm.calls.strict_argument_naming (&args_so_far)
2412 || ! targetm.calls.pretend_outgoing_varargs_named (&args_so_far))
2413 && type_arg_types != 0)
2415 = (list_length (type_arg_types)
2416 /* Don't include the last named arg. */
2417 - (targetm.calls.strict_argument_naming (&args_so_far) ? 0 : 1)
2418 /* Count the struct value address, if it is passed as a parm. */
2419 + structure_value_addr_parm);
2421 /* If we know nothing, treat all args as named. */
2422 n_named_args = num_actuals;
2424 /* Start updating where the next arg would go.
2426 On some machines (such as the PA) indirect calls have a different
2427 calling convention than normal calls. The fourth argument in
2428 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2430 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, fndecl, n_named_args);
2432 /* Make a vector to hold all the information about each arg. */
2433 args = alloca (num_actuals * sizeof (struct arg_data));
2434 memset (args, 0, num_actuals * sizeof (struct arg_data));
2436 /* Build up entries in the ARGS array, compute the size of the
2437 arguments into ARGS_SIZE, etc. */
2438 initialize_argument_information (num_actuals, args, &args_size,
2439 n_named_args, actparms, fndecl,
2440 &args_so_far, reg_parm_stack_space,
2441 &old_stack_level, &old_pending_adj,
2442 &must_preallocate, &flags,
2443 CALL_FROM_THUNK_P (exp));
2447 /* If this function requires a variable-sized argument list, don't
2448 try to make a cse'able block for this call. We may be able to
2449 do this eventually, but it is too complicated to keep track of
2450 what insns go in the cse'able block and which don't. */
2452 flags &= ~ECF_LIBCALL_BLOCK;
2453 must_preallocate = 1;
2456 /* Now make final decision about preallocating stack space. */
2457 must_preallocate = finalize_must_preallocate (must_preallocate,
2461 /* If the structure value address will reference the stack pointer, we
2462 must stabilize it. We don't need to do this if we know that we are
2463 not going to adjust the stack pointer in processing this call. */
2465 if (structure_value_addr
2466 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2467 || reg_mentioned_p (virtual_outgoing_args_rtx,
2468 structure_value_addr))
2470 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2471 structure_value_addr = copy_to_reg (structure_value_addr);
2473 /* Tail calls can make things harder to debug, and we're traditionally
2474 pushed these optimizations into -O2. Don't try if we're already
2475 expanding a call, as that means we're an argument. Don't try if
2476 there's cleanups, as we know there's code to follow the call.
2478 If rtx_equal_function_value_matters is false, that means we've
2479 finished with regular parsing. Which means that some of the
2480 machinery we use to generate tail-calls is no longer in place.
2481 This is most often true of sjlj-exceptions, which we couldn't
2482 tail-call to anyway.
2484 If current_nesting_level () == 0, we're being called after
2485 the function body has been expanded. This can happen when
2486 setting up trampolines in expand_function_end. */
2487 if (currently_expanding_call++ != 0
2488 || !flag_optimize_sibling_calls
2489 || !rtx_equal_function_value_matters
2490 || current_nesting_level () == 0
2491 || any_pending_cleanups ()
2493 try_tail_call = try_tail_recursion = 0;
2495 /* Tail recursion fails, when we are not dealing with recursive calls. */
2496 if (!try_tail_recursion
2497 || TREE_CODE (addr) != ADDR_EXPR
2498 || TREE_OPERAND (addr, 0) != current_function_decl)
2499 try_tail_recursion = 0;
2501 /* Rest of purposes for tail call optimizations to fail. */
2503 #ifdef HAVE_sibcall_epilogue
2504 !HAVE_sibcall_epilogue
2509 /* Doing sibling call optimization needs some work, since
2510 structure_value_addr can be allocated on the stack.
2511 It does not seem worth the effort since few optimizable
2512 sibling calls will return a structure. */
2513 || structure_value_addr != NULL_RTX
2514 /* Check whether the target is able to optimize the call
2516 || !targetm.function_ok_for_sibcall (fndecl, exp)
2517 /* Functions that do not return exactly once may not be sibcall
2519 || (flags & (ECF_RETURNS_TWICE | ECF_LONGJMP | ECF_NORETURN))
2520 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr)))
2521 /* If the called function is nested in the current one, it might access
2522 some of the caller's arguments, but could clobber them beforehand if
2523 the argument areas are shared. */
2524 || (fndecl && decl_function_context (fndecl) == current_function_decl)
2525 /* If this function requires more stack slots than the current
2526 function, we cannot change it into a sibling call. */
2527 || args_size.constant > current_function_args_size
2528 /* If the callee pops its own arguments, then it must pop exactly
2529 the same number of arguments as the current function. */
2530 || (RETURN_POPS_ARGS (fndecl, funtype, args_size.constant)
2531 != RETURN_POPS_ARGS (current_function_decl,
2532 TREE_TYPE (current_function_decl),
2533 current_function_args_size))
2534 || !lang_hooks.decls.ok_for_sibcall (fndecl))
2537 if (try_tail_call || try_tail_recursion)
2540 actparms = NULL_TREE;
2541 /* Ok, we're going to give the tail call the old college try.
2542 This means we're going to evaluate the function arguments
2543 up to three times. There are two degrees of badness we can
2544 encounter, those that can be unsaved and those that can't.
2545 (See unsafe_for_reeval commentary for details.)
2547 Generate a new argument list. Pass safe arguments through
2548 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2549 For hard badness, evaluate them now and put their resulting
2550 rtx in a temporary VAR_DECL.
2552 initialize_argument_information has ordered the array for the
2553 order to be pushed, and we must remember this when reconstructing
2554 the original argument order. */
2556 if (PUSH_ARGS_REVERSED)
2565 i = num_actuals - 1;
2569 for (; i != end; i += inc)
2571 args[i].tree_value = fix_unsafe_tree (args[i].tree_value);
2572 /* We need to build actparms for optimize_tail_recursion. We can
2573 safely trash away TREE_PURPOSE, since it is unused by this
2575 if (try_tail_recursion)
2576 actparms = tree_cons (NULL_TREE, args[i].tree_value, actparms);
2578 /* Do the same for the function address if it is an expression. */
2580 addr = fix_unsafe_tree (addr);
2581 /* Expanding one of those dangerous arguments could have added
2582 cleanups, but otherwise give it a whirl. */
2583 if (any_pending_cleanups ())
2584 try_tail_call = try_tail_recursion = 0;
2587 /* Generate a tail recursion sequence when calling ourselves. */
2589 if (try_tail_recursion)
2591 /* We want to emit any pending stack adjustments before the tail
2592 recursion "call". That way we know any adjustment after the tail
2593 recursion call can be ignored if we indeed use the tail recursion
2595 int save_pending_stack_adjust = pending_stack_adjust;
2596 int save_stack_pointer_delta = stack_pointer_delta;
2598 /* Emit any queued insns now; otherwise they would end up in
2599 only one of the alternates. */
2602 /* Use a new sequence to hold any RTL we generate. We do not even
2603 know if we will use this RTL yet. The final decision can not be
2604 made until after RTL generation for the entire function is
2607 /* If expanding any of the arguments creates cleanups, we can't
2608 do a tailcall. So, we'll need to pop the pending cleanups
2609 list. If, however, all goes well, and there are no cleanups
2610 then the call to expand_start_target_temps will have no
2612 expand_start_target_temps ();
2613 if (optimize_tail_recursion (actparms, get_last_insn ()))
2615 if (any_pending_cleanups ())
2616 try_tail_call = try_tail_recursion = 0;
2618 tail_recursion_insns = get_insns ();
2620 expand_end_target_temps ();
2623 /* Restore the original pending stack adjustment for the sibling and
2624 normal call cases below. */
2625 pending_stack_adjust = save_pending_stack_adjust;
2626 stack_pointer_delta = save_stack_pointer_delta;
2629 if (profile_arc_flag && (flags & ECF_FORK_OR_EXEC))
2631 /* A fork duplicates the profile information, and an exec discards
2632 it. We can't rely on fork/exec to be paired. So write out the
2633 profile information we have gathered so far, and clear it. */
2634 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2635 is subject to race conditions, just as with multithreaded
2638 emit_library_call (gcov_flush_libfunc, LCT_ALWAYS_RETURN, VOIDmode, 0);
2641 /* Ensure current function's preferred stack boundary is at least
2642 what we need. We don't have to increase alignment for recursive
2644 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2645 && fndecl != current_function_decl)
2646 cfun->preferred_stack_boundary = preferred_stack_boundary;
2647 if (fndecl == current_function_decl)
2648 cfun->recursive_call_emit = true;
2650 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2652 function_call_count++;
2654 /* We want to make two insn chains; one for a sibling call, the other
2655 for a normal call. We will select one of the two chains after
2656 initial RTL generation is complete. */
2657 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
2659 int sibcall_failure = 0;
2660 /* We want to emit any pending stack adjustments before the tail
2661 recursion "call". That way we know any adjustment after the tail
2662 recursion call can be ignored if we indeed use the tail recursion
2664 int save_pending_stack_adjust = 0;
2665 int save_stack_pointer_delta = 0;
2667 rtx before_call, next_arg_reg;
2671 /* Emit any queued insns now; otherwise they would end up in
2672 only one of the alternates. */
2675 /* State variables we need to save and restore between
2677 save_pending_stack_adjust = pending_stack_adjust;
2678 save_stack_pointer_delta = stack_pointer_delta;
2681 flags &= ~ECF_SIBCALL;
2683 flags |= ECF_SIBCALL;
2685 /* Other state variables that we must reinitialize each time
2686 through the loop (that are not initialized by the loop itself). */
2690 /* Start a new sequence for the normal call case.
2692 From this point on, if the sibling call fails, we want to set
2693 sibcall_failure instead of continuing the loop. */
2698 /* We know at this point that there are not currently any
2699 pending cleanups. If, however, in the process of evaluating
2700 the arguments we were to create some, we'll need to be
2701 able to get rid of them. */
2702 expand_start_target_temps ();
2705 /* Don't let pending stack adjusts add up to too much.
2706 Also, do all pending adjustments now if there is any chance
2707 this might be a call to alloca or if we are expanding a sibling
2708 call sequence or if we are calling a function that is to return
2709 with stack pointer depressed. */
2710 if (pending_stack_adjust >= 32
2711 || (pending_stack_adjust > 0
2712 && (flags & (ECF_MAY_BE_ALLOCA | ECF_SP_DEPRESSED)))
2714 do_pending_stack_adjust ();
2716 /* When calling a const function, we must pop the stack args right away,
2717 so that the pop is deleted or moved with the call. */
2718 if (pass && (flags & ECF_LIBCALL_BLOCK))
2721 /* Precompute any arguments as needed. */
2723 precompute_arguments (flags, num_actuals, args);
2725 /* Now we are about to start emitting insns that can be deleted
2726 if a libcall is deleted. */
2727 if (pass && (flags & (ECF_LIBCALL_BLOCK | ECF_MALLOC)))
2730 adjusted_args_size = args_size;
2731 /* Compute the actual size of the argument block required. The variable
2732 and constant sizes must be combined, the size may have to be rounded,
2733 and there may be a minimum required size. When generating a sibcall
2734 pattern, do not round up, since we'll be re-using whatever space our
2736 unadjusted_args_size
2737 = compute_argument_block_size (reg_parm_stack_space,
2738 &adjusted_args_size,
2740 : preferred_stack_boundary));
2742 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2744 /* The argument block when performing a sibling call is the
2745 incoming argument block. */
2748 argblock = virtual_incoming_args_rtx;
2750 #ifdef STACK_GROWS_DOWNWARD
2751 = plus_constant (argblock, current_function_pretend_args_size);
2753 = plus_constant (argblock, -current_function_pretend_args_size);
2755 stored_args_map = sbitmap_alloc (args_size.constant);
2756 sbitmap_zero (stored_args_map);
2759 /* If we have no actual push instructions, or shouldn't use them,
2760 make space for all args right now. */
2761 else if (adjusted_args_size.var != 0)
2763 if (old_stack_level == 0)
2765 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2766 old_stack_pointer_delta = stack_pointer_delta;
2767 old_pending_adj = pending_stack_adjust;
2768 pending_stack_adjust = 0;
2769 /* stack_arg_under_construction says whether a stack arg is
2770 being constructed at the old stack level. Pushing the stack
2771 gets a clean outgoing argument block. */
2772 old_stack_arg_under_construction = stack_arg_under_construction;
2773 stack_arg_under_construction = 0;
2775 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2779 /* Note that we must go through the motions of allocating an argument
2780 block even if the size is zero because we may be storing args
2781 in the area reserved for register arguments, which may be part of
2784 int needed = adjusted_args_size.constant;
2786 /* Store the maximum argument space used. It will be pushed by
2787 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2790 if (needed > current_function_outgoing_args_size)
2791 current_function_outgoing_args_size = needed;
2793 if (must_preallocate)
2795 if (ACCUMULATE_OUTGOING_ARGS)
2797 /* Since the stack pointer will never be pushed, it is
2798 possible for the evaluation of a parm to clobber
2799 something we have already written to the stack.
2800 Since most function calls on RISC machines do not use
2801 the stack, this is uncommon, but must work correctly.
2803 Therefore, we save any area of the stack that was already
2804 written and that we are using. Here we set up to do this
2805 by making a new stack usage map from the old one. The
2806 actual save will be done by store_one_arg.
2808 Another approach might be to try to reorder the argument
2809 evaluations to avoid this conflicting stack usage. */
2811 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2812 /* Since we will be writing into the entire argument area,
2813 the map must be allocated for its entire size, not just
2814 the part that is the responsibility of the caller. */
2815 needed += reg_parm_stack_space;
2818 #ifdef ARGS_GROW_DOWNWARD
2819 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2822 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2825 stack_usage_map = alloca (highest_outgoing_arg_in_use);
2827 if (initial_highest_arg_in_use)
2828 memcpy (stack_usage_map, initial_stack_usage_map,
2829 initial_highest_arg_in_use);
2831 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2832 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2833 (highest_outgoing_arg_in_use
2834 - initial_highest_arg_in_use));
2837 /* The address of the outgoing argument list must not be
2838 copied to a register here, because argblock would be left
2839 pointing to the wrong place after the call to
2840 allocate_dynamic_stack_space below. */
2842 argblock = virtual_outgoing_args_rtx;
2846 if (inhibit_defer_pop == 0)
2848 /* Try to reuse some or all of the pending_stack_adjust
2849 to get this space. */
2851 = (combine_pending_stack_adjustment_and_call
2852 (unadjusted_args_size,
2853 &adjusted_args_size,
2854 preferred_unit_stack_boundary));
2856 /* combine_pending_stack_adjustment_and_call computes
2857 an adjustment before the arguments are allocated.
2858 Account for them and see whether or not the stack
2859 needs to go up or down. */
2860 needed = unadjusted_args_size - needed;
2864 /* We're releasing stack space. */
2865 /* ??? We can avoid any adjustment at all if we're
2866 already aligned. FIXME. */
2867 pending_stack_adjust = -needed;
2868 do_pending_stack_adjust ();
2872 /* We need to allocate space. We'll do that in
2873 push_block below. */
2874 pending_stack_adjust = 0;
2877 /* Special case this because overhead of `push_block' in
2878 this case is non-trivial. */
2880 argblock = virtual_outgoing_args_rtx;
2883 argblock = push_block (GEN_INT (needed), 0, 0);
2884 #ifdef ARGS_GROW_DOWNWARD
2885 argblock = plus_constant (argblock, needed);
2889 /* We only really need to call `copy_to_reg' in the case
2890 where push insns are going to be used to pass ARGBLOCK
2891 to a function call in ARGS. In that case, the stack
2892 pointer changes value from the allocation point to the
2893 call point, and hence the value of
2894 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2895 as well always do it. */
2896 argblock = copy_to_reg (argblock);
2901 if (ACCUMULATE_OUTGOING_ARGS)
2903 /* The save/restore code in store_one_arg handles all
2904 cases except one: a constructor call (including a C
2905 function returning a BLKmode struct) to initialize
2907 if (stack_arg_under_construction)
2909 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2910 rtx push_size = GEN_INT (reg_parm_stack_space
2911 + adjusted_args_size.constant);
2913 rtx push_size = GEN_INT (adjusted_args_size.constant);
2915 if (old_stack_level == 0)
2917 emit_stack_save (SAVE_BLOCK, &old_stack_level,
2919 old_stack_pointer_delta = stack_pointer_delta;
2920 old_pending_adj = pending_stack_adjust;
2921 pending_stack_adjust = 0;
2922 /* stack_arg_under_construction says whether a stack
2923 arg is being constructed at the old stack level.
2924 Pushing the stack gets a clean outgoing argument
2926 old_stack_arg_under_construction
2927 = stack_arg_under_construction;
2928 stack_arg_under_construction = 0;
2929 /* Make a new map for the new argument list. */
2930 stack_usage_map = alloca (highest_outgoing_arg_in_use);
2931 memset (stack_usage_map, 0, highest_outgoing_arg_in_use);
2932 highest_outgoing_arg_in_use = 0;
2934 allocate_dynamic_stack_space (push_size, NULL_RTX,
2938 /* If argument evaluation might modify the stack pointer,
2939 copy the address of the argument list to a register. */
2940 for (i = 0; i < num_actuals; i++)
2941 if (args[i].pass_on_stack)
2943 argblock = copy_addr_to_reg (argblock);
2948 compute_argument_addresses (args, argblock, num_actuals);
2950 /* If we push args individually in reverse order, perform stack alignment
2951 before the first push (the last arg). */
2952 if (PUSH_ARGS_REVERSED && argblock == 0
2953 && adjusted_args_size.constant != unadjusted_args_size)
2955 /* When the stack adjustment is pending, we get better code
2956 by combining the adjustments. */
2957 if (pending_stack_adjust
2958 && ! (flags & ECF_LIBCALL_BLOCK)
2959 && ! inhibit_defer_pop)
2961 pending_stack_adjust
2962 = (combine_pending_stack_adjustment_and_call
2963 (unadjusted_args_size,
2964 &adjusted_args_size,
2965 preferred_unit_stack_boundary));
2966 do_pending_stack_adjust ();
2968 else if (argblock == 0)
2969 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2970 - unadjusted_args_size));
2972 /* Now that the stack is properly aligned, pops can't safely
2973 be deferred during the evaluation of the arguments. */
2976 funexp = rtx_for_function_call (fndecl, addr);
2978 /* Figure out the register where the value, if any, will come back. */
2980 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2981 && ! structure_value_addr)
2983 if (pcc_struct_value)
2984 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2985 fndecl, (pass == 0));
2987 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
2990 /* Precompute all register parameters. It isn't safe to compute anything
2991 once we have started filling any specific hard regs. */
2992 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2994 #ifdef REG_PARM_STACK_SPACE
2995 /* Save the fixed argument area if it's part of the caller's frame and
2996 is clobbered by argument setup for this call. */
2997 if (ACCUMULATE_OUTGOING_ARGS && pass)
2998 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2999 &low_to_save, &high_to_save);
3002 /* Now store (and compute if necessary) all non-register parms.
3003 These come before register parms, since they can require block-moves,
3004 which could clobber the registers used for register parms.
3005 Parms which have partial registers are not stored here,
3006 but we do preallocate space here if they want that. */
3008 for (i = 0; i < num_actuals; i++)
3009 if (args[i].reg == 0 || args[i].pass_on_stack)
3011 rtx before_arg = get_last_insn ();
3013 if (store_one_arg (&args[i], argblock, flags,
3014 adjusted_args_size.var != 0,
3015 reg_parm_stack_space)
3017 && check_sibcall_argument_overlap (before_arg,
3019 sibcall_failure = 1;
3021 if (flags & ECF_CONST
3023 && args[i].value == args[i].stack)
3024 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3025 gen_rtx_USE (VOIDmode,
3030 /* If we have a parm that is passed in registers but not in memory
3031 and whose alignment does not permit a direct copy into registers,
3032 make a group of pseudos that correspond to each register that we
3034 if (STRICT_ALIGNMENT)
3035 store_unaligned_arguments_into_pseudos (args, num_actuals);
3037 /* Now store any partially-in-registers parm.
3038 This is the last place a block-move can happen. */
3040 for (i = 0; i < num_actuals; i++)
3041 if (args[i].partial != 0 && ! args[i].pass_on_stack)
3043 rtx before_arg = get_last_insn ();
3045 if (store_one_arg (&args[i], argblock, flags,
3046 adjusted_args_size.var != 0,
3047 reg_parm_stack_space)
3049 && check_sibcall_argument_overlap (before_arg,
3051 sibcall_failure = 1;
3054 /* If we pushed args in forward order, perform stack alignment
3055 after pushing the last arg. */
3056 if (!PUSH_ARGS_REVERSED && argblock == 0)
3057 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3058 - unadjusted_args_size));
3060 /* If register arguments require space on the stack and stack space
3061 was not preallocated, allocate stack space here for arguments
3062 passed in registers. */
3063 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3064 if (!ACCUMULATE_OUTGOING_ARGS
3065 && must_preallocate == 0 && reg_parm_stack_space > 0)
3066 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3069 /* Pass the function the address in which to return a
3071 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3073 structure_value_addr
3074 = convert_memory_address (Pmode, structure_value_addr);
3075 emit_move_insn (struct_value,
3077 force_operand (structure_value_addr,
3080 if (GET_CODE (struct_value) == REG)
3081 use_reg (&call_fusage, struct_value);
3084 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
3085 reg_parm_seen, pass == 0);
3087 load_register_parameters (args, num_actuals, &call_fusage, flags,
3088 pass == 0, &sibcall_failure);
3090 /* Perform postincrements before actually calling the function. */
3093 /* Save a pointer to the last insn before the call, so that we can
3094 later safely search backwards to find the CALL_INSN. */
3095 before_call = get_last_insn ();
3097 /* Set up next argument register. For sibling calls on machines
3098 with register windows this should be the incoming register. */
3099 #ifdef FUNCTION_INCOMING_ARG
3101 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
3105 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
3108 /* All arguments and registers used for the call must be set up by
3111 /* Stack must be properly aligned now. */
3112 if (pass && stack_pointer_delta % preferred_unit_stack_boundary)
3115 /* Generate the actual call instruction. */
3116 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
3117 adjusted_args_size.constant, struct_value_size,
3118 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3119 flags, & args_so_far);
3121 /* If call is cse'able, make appropriate pair of reg-notes around it.
3122 Test valreg so we don't crash; may safely ignore `const'
3123 if return type is void. Disable for PARALLEL return values, because
3124 we have no way to move such values into a pseudo register. */
3125 if (pass && (flags & ECF_LIBCALL_BLOCK))
3129 bool failed = valreg == 0 || GET_CODE (valreg) == PARALLEL;
3131 insns = get_insns ();
3133 /* Expansion of block moves possibly introduced a loop that may
3134 not appear inside libcall block. */
3135 for (insn = insns; insn; insn = NEXT_INSN (insn))
3136 if (GET_CODE (insn) == JUMP_INSN)
3147 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3149 /* Mark the return value as a pointer if needed. */
3150 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3151 mark_reg_pointer (temp,
3152 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
3155 if (flag_unsafe_math_optimizations
3157 && DECL_BUILT_IN (fndecl)
3158 && (DECL_FUNCTION_CODE (fndecl) == BUILT_IN_SQRT
3159 || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_SQRTF
3160 || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_SQRTL))
3161 note = gen_rtx_fmt_e (SQRT,
3163 args[0].initial_value);
3166 /* Construct an "equal form" for the value which
3167 mentions all the arguments in order as well as
3168 the function name. */
3169 for (i = 0; i < num_actuals; i++)
3170 note = gen_rtx_EXPR_LIST (VOIDmode,
3171 args[i].initial_value, note);
3172 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
3174 if (flags & ECF_PURE)
3175 note = gen_rtx_EXPR_LIST (VOIDmode,
3176 gen_rtx_USE (VOIDmode,
3177 gen_rtx_MEM (BLKmode,
3178 gen_rtx_SCRATCH (VOIDmode))),
3181 emit_libcall_block (insns, temp, valreg, note);
3186 else if (pass && (flags & ECF_MALLOC))
3188 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3191 /* The return value from a malloc-like function is a pointer. */
3192 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3193 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3195 emit_move_insn (temp, valreg);
3197 /* The return value from a malloc-like function can not alias
3199 last = get_last_insn ();
3201 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
3203 /* Write out the sequence. */
3204 insns = get_insns ();
3210 /* For calls to `setjmp', etc., inform flow.c it should complain
3211 if nonvolatile values are live. For functions that cannot return,
3212 inform flow that control does not fall through. */
3214 if ((flags & (ECF_NORETURN | ECF_LONGJMP)) || pass == 0)
3216 /* The barrier must be emitted
3217 immediately after the CALL_INSN. Some ports emit more
3218 than just a CALL_INSN above, so we must search for it here. */
3220 rtx last = get_last_insn ();
3221 while (GET_CODE (last) != CALL_INSN)
3223 last = PREV_INSN (last);
3224 /* There was no CALL_INSN? */
3225 if (last == before_call)
3229 emit_barrier_after (last);
3231 /* Stack adjustments after a noreturn call are dead code.
3232 However when NO_DEFER_POP is in effect, we must preserve
3233 stack_pointer_delta. */
3234 if (inhibit_defer_pop == 0)
3236 stack_pointer_delta = old_stack_allocated;
3237 pending_stack_adjust = 0;
3241 if (flags & ECF_LONGJMP)
3242 current_function_calls_longjmp = 1;
3244 /* If value type not void, return an rtx for the value. */
3246 /* If there are cleanups to be called, don't use a hard reg as target.
3247 We need to double check this and see if it matters anymore. */
3248 if (any_pending_cleanups ())
3250 if (target && REG_P (target)
3251 && REGNO (target) < FIRST_PSEUDO_REGISTER)
3253 sibcall_failure = 1;
3256 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
3258 target = const0_rtx;
3259 else if (structure_value_addr)
3261 if (target == 0 || GET_CODE (target) != MEM)
3264 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3265 memory_address (TYPE_MODE (TREE_TYPE (exp)),
3266 structure_value_addr));
3267 set_mem_attributes (target, exp, 1);
3270 else if (pcc_struct_value)
3272 /* This is the special C++ case where we need to
3273 know what the true target was. We take care to
3274 never use this value more than once in one expression. */
3275 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3276 copy_to_reg (valreg));
3277 set_mem_attributes (target, exp, 1);
3279 /* Handle calls that return values in multiple non-contiguous locations.
3280 The Irix 6 ABI has examples of this. */
3281 else if (GET_CODE (valreg) == PARALLEL)
3283 /* Second condition is added because "target" is freed at the
3284 the end of "pass0" for -O2 when call is made to
3285 expand_end_target_temps (). Its "in_use" flag has been set
3286 to false, so allocate a new temp. */
3287 if (target == 0 || (pass == 1 && target == temp_target))
3289 /* This will only be assigned once, so it can be readonly. */
3290 tree nt = build_qualified_type (TREE_TYPE (exp),
3291 (TYPE_QUALS (TREE_TYPE (exp))
3292 | TYPE_QUAL_CONST));
3294 target = assign_temp (nt, 0, 1, 1);
3295 temp_target = target;
3296 preserve_temp_slots (target);
3299 if (! rtx_equal_p (target, valreg))
3300 emit_group_store (target, valreg, TREE_TYPE (exp),
3301 int_size_in_bytes (TREE_TYPE (exp)));
3303 /* We can not support sibling calls for this case. */
3304 sibcall_failure = 1;
3307 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
3308 && GET_MODE (target) == GET_MODE (valreg))
3310 /* TARGET and VALREG cannot be equal at this point because the
3311 latter would not have REG_FUNCTION_VALUE_P true, while the
3312 former would if it were referring to the same register.
3314 If they refer to the same register, this move will be a no-op,
3315 except when function inlining is being done. */
3316 emit_move_insn (target, valreg);
3318 /* If we are setting a MEM, this code must be executed. Since it is
3319 emitted after the call insn, sibcall optimization cannot be
3320 performed in that case. */
3321 if (GET_CODE (target) == MEM)
3322 sibcall_failure = 1;
3324 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3326 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3328 /* We can not support sibling calls for this case. */
3329 sibcall_failure = 1;
3333 if (shift_returned_value (TREE_TYPE (exp), &valreg))
3334 sibcall_failure = 1;
3336 target = copy_to_reg (valreg);
3339 if (targetm.calls.promote_function_return(funtype))
3341 /* If we promoted this return value, make the proper SUBREG. TARGET
3342 might be const0_rtx here, so be careful. */
3343 if (GET_CODE (target) == REG
3344 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3345 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3347 tree type = TREE_TYPE (exp);
3348 int unsignedp = TYPE_UNSIGNED (type);
3351 /* If we don't promote as expected, something is wrong. */
3352 if (GET_MODE (target)
3353 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
3356 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3357 && GET_MODE_SIZE (GET_MODE (target))
3358 > GET_MODE_SIZE (TYPE_MODE (type)))
3360 offset = GET_MODE_SIZE (GET_MODE (target))
3361 - GET_MODE_SIZE (TYPE_MODE (type));
3362 if (! BYTES_BIG_ENDIAN)
3363 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3364 else if (! WORDS_BIG_ENDIAN)
3365 offset %= UNITS_PER_WORD;
3367 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3368 SUBREG_PROMOTED_VAR_P (target) = 1;
3369 SUBREG_PROMOTED_UNSIGNED_SET (target, unsignedp);
3373 /* If size of args is variable or this was a constructor call for a stack
3374 argument, restore saved stack-pointer value. */
3376 if (old_stack_level && ! (flags & ECF_SP_DEPRESSED))
3378 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3379 stack_pointer_delta = old_stack_pointer_delta;
3380 pending_stack_adjust = old_pending_adj;
3381 stack_arg_under_construction = old_stack_arg_under_construction;
3382 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3383 stack_usage_map = initial_stack_usage_map;
3384 sibcall_failure = 1;
3386 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3388 #ifdef REG_PARM_STACK_SPACE
3390 restore_fixed_argument_area (save_area, argblock,
3391 high_to_save, low_to_save);
3394 /* If we saved any argument areas, restore them. */
3395 for (i = 0; i < num_actuals; i++)
3396 if (args[i].save_area)
3398 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3400 = gen_rtx_MEM (save_mode,
3401 memory_address (save_mode,
3402 XEXP (args[i].stack_slot, 0)));
3404 if (save_mode != BLKmode)
3405 emit_move_insn (stack_area, args[i].save_area);
3407 emit_block_move (stack_area, args[i].save_area,
3408 GEN_INT (args[i].locate.size.constant),
3409 BLOCK_OP_CALL_PARM);
3412 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3413 stack_usage_map = initial_stack_usage_map;
3416 /* If this was alloca, record the new stack level for nonlocal gotos.
3417 Check for the handler slots since we might not have a save area
3418 for non-local gotos. */
3420 if ((flags & ECF_MAY_BE_ALLOCA) && nonlocal_goto_handler_slots != 0)
3421 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3423 /* Free up storage we no longer need. */
3424 for (i = 0; i < num_actuals; ++i)
3425 if (args[i].aligned_regs)
3426 free (args[i].aligned_regs);
3430 /* Undo the fake expand_start_target_temps we did earlier. If
3431 there had been any cleanups created, we've already set
3433 expand_end_target_temps ();
3436 /* If this function is returning into a memory location marked as
3437 readonly, it means it is initializing that location. We normally treat
3438 functions as not clobbering such locations, so we need to specify that
3439 this one does. We do this by adding the appropriate CLOBBER to the
3440 CALL_INSN function usage list. This cannot be done by emitting a
3441 standalone CLOBBER after the call because the latter would be ignored
3442 by at least the delay slot scheduling pass. We do this now instead of
3443 adding to call_fusage before the call to emit_call_1 because TARGET
3444 may be modified in the meantime. */
3445 if (structure_value_addr != 0 && target != 0
3446 && GET_CODE (target) == MEM && RTX_UNCHANGING_P (target))
3447 add_function_usage_to
3449 gen_rtx_EXPR_LIST (VOIDmode, gen_rtx_CLOBBER (VOIDmode, target),
3452 insns = get_insns ();
3457 tail_call_insns = insns;
3459 /* Restore the pending stack adjustment now that we have
3460 finished generating the sibling call sequence. */
3462 pending_stack_adjust = save_pending_stack_adjust;
3463 stack_pointer_delta = save_stack_pointer_delta;
3465 /* Prepare arg structure for next iteration. */
3466 for (i = 0; i < num_actuals; i++)
3469 args[i].aligned_regs = 0;
3473 sbitmap_free (stored_args_map);
3477 normal_call_insns = insns;
3479 /* Verify that we've deallocated all the stack we used. */
3480 if (! (flags & (ECF_NORETURN | ECF_LONGJMP))
3481 && old_stack_allocated != stack_pointer_delta
3482 - pending_stack_adjust)
3486 /* If something prevents making this a sibling call,
3487 zero out the sequence. */
3488 if (sibcall_failure)
3489 tail_call_insns = NULL_RTX;
3492 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3493 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3494 can happen if the arguments to this function call an inline
3495 function who's expansion contains another CALL_PLACEHOLDER.
3497 If there are any C_Ps in any of these sequences, replace them
3498 with their normal call. */
3500 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3501 if (GET_CODE (insn) == CALL_INSN
3502 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3503 replace_call_placeholder (insn, sibcall_use_normal);
3505 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
3506 if (GET_CODE (insn) == CALL_INSN
3507 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3508 replace_call_placeholder (insn, sibcall_use_normal);
3510 for (insn = tail_recursion_insns; insn; insn = NEXT_INSN (insn))
3511 if (GET_CODE (insn) == CALL_INSN
3512 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3513 replace_call_placeholder (insn, sibcall_use_normal);
3515 /* If this was a potential tail recursion site, then emit a
3516 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3517 One of them will be selected later. */
3518 if (tail_recursion_insns || tail_call_insns)
3520 /* The tail recursion label must be kept around. We could expose
3521 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3522 and makes determining true tail recursion sites difficult.
3524 So we set LABEL_PRESERVE_P here, then clear it when we select
3525 one of the call sequences after rtl generation is complete. */
3526 if (tail_recursion_insns)
3527 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3528 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3530 tail_recursion_insns,
3531 tail_recursion_label));
3534 emit_insn (normal_call_insns);
3536 currently_expanding_call--;
3538 /* If this function returns with the stack pointer depressed, ensure
3539 this block saves and restores the stack pointer, show it was
3540 changed, and adjust for any outgoing arg space. */
3541 if (flags & ECF_SP_DEPRESSED)
3543 clear_pending_stack_adjust ();
3544 emit_insn (gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx));
3545 emit_move_insn (virtual_stack_dynamic_rtx, stack_pointer_rtx);
3546 save_stack_pointer ();
3552 /* Traverse an argument list in VALUES and expand all complex
3553 arguments into their components. */
3555 split_complex_values (tree values)
3559 /* Before allocating memory, check for the common case of no complex. */
3560 for (p = values; p; p = TREE_CHAIN (p))
3562 tree type = TREE_TYPE (TREE_VALUE (p));
3563 if (type && TREE_CODE (type) == COMPLEX_TYPE
3564 && targetm.calls.split_complex_arg (type))
3570 values = copy_list (values);
3572 for (p = values; p; p = TREE_CHAIN (p))
3574 tree complex_value = TREE_VALUE (p);
3577 complex_type = TREE_TYPE (complex_value);
3581 if (TREE_CODE (complex_type) == COMPLEX_TYPE
3582 && targetm.calls.split_complex_arg (complex_type))
3585 tree real, imag, next;
3587 subtype = TREE_TYPE (complex_type);
3588 complex_value = save_expr (complex_value);
3589 real = build1 (REALPART_EXPR, subtype, complex_value);
3590 imag = build1 (IMAGPART_EXPR, subtype, complex_value);
3592 TREE_VALUE (p) = real;
3593 next = TREE_CHAIN (p);
3594 imag = build_tree_list (NULL_TREE, imag);
3595 TREE_CHAIN (p) = imag;
3596 TREE_CHAIN (imag) = next;
3598 /* Skip the newly created node. */
3606 /* Traverse a list of TYPES and expand all complex types into their
3609 split_complex_types (tree types)
3613 /* Before allocating memory, check for the common case of no complex. */
3614 for (p = types; p; p = TREE_CHAIN (p))
3616 tree type = TREE_VALUE (p);
3617 if (TREE_CODE (type) == COMPLEX_TYPE
3618 && targetm.calls.split_complex_arg (type))
3624 types = copy_list (types);
3626 for (p = types; p; p = TREE_CHAIN (p))
3628 tree complex_type = TREE_VALUE (p);
3630 if (TREE_CODE (complex_type) == COMPLEX_TYPE
3631 && targetm.calls.split_complex_arg (complex_type))
3635 /* Rewrite complex type with component type. */
3636 TREE_VALUE (p) = TREE_TYPE (complex_type);
3637 next = TREE_CHAIN (p);
3639 /* Add another component type for the imaginary part. */
3640 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
3641 TREE_CHAIN (p) = imag;
3642 TREE_CHAIN (imag) = next;
3644 /* Skip the newly created node. */
3652 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3653 The RETVAL parameter specifies whether return value needs to be saved, other
3654 parameters are documented in the emit_library_call function below. */
3657 emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
3658 enum libcall_type fn_type,
3659 enum machine_mode outmode, int nargs, va_list p)
3661 /* Total size in bytes of all the stack-parms scanned so far. */
3662 struct args_size args_size;
3663 /* Size of arguments before any adjustments (such as rounding). */
3664 struct args_size original_args_size;
3670 CUMULATIVE_ARGS args_so_far;
3674 enum machine_mode mode;
3677 struct locate_and_pad_arg_data locate;
3681 int old_inhibit_defer_pop = inhibit_defer_pop;
3682 rtx call_fusage = 0;
3685 int pcc_struct_value = 0;
3686 int struct_value_size = 0;
3688 int reg_parm_stack_space = 0;
3691 tree tfom; /* type_for_mode (outmode, 0) */
3693 #ifdef REG_PARM_STACK_SPACE
3694 /* Define the boundary of the register parm stack space that needs to be
3696 int low_to_save, high_to_save;
3697 rtx save_area = 0; /* Place that it is saved. */
3700 /* Size of the stack reserved for parameter registers. */
3701 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3702 char *initial_stack_usage_map = stack_usage_map;
3704 rtx struct_value = targetm.calls.struct_value_rtx (0, 0);
3706 #ifdef REG_PARM_STACK_SPACE
3707 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3710 /* By default, library functions can not throw. */
3711 flags = ECF_NOTHROW;
3723 case LCT_CONST_MAKE_BLOCK:
3724 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
3726 case LCT_PURE_MAKE_BLOCK:
3727 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
3730 flags |= ECF_NORETURN;
3733 flags = ECF_NORETURN;
3735 case LCT_ALWAYS_RETURN:
3736 flags = ECF_ALWAYS_RETURN;
3738 case LCT_RETURNS_TWICE:
3739 flags = ECF_RETURNS_TWICE;
3744 /* Ensure current function's preferred stack boundary is at least
3746 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3747 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3749 /* If this kind of value comes back in memory,
3750 decide where in memory it should come back. */
3751 if (outmode != VOIDmode)
3753 tfom = lang_hooks.types.type_for_mode (outmode, 0);
3754 if (aggregate_value_p (tfom, 0))
3756 #ifdef PCC_STATIC_STRUCT_RETURN
3758 = hard_function_value (build_pointer_type (tfom), 0, 0);
3759 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3760 pcc_struct_value = 1;
3762 value = gen_reg_rtx (outmode);
3763 #else /* not PCC_STATIC_STRUCT_RETURN */
3764 struct_value_size = GET_MODE_SIZE (outmode);
3765 if (value != 0 && GET_CODE (value) == MEM)
3768 mem_value = assign_temp (tfom, 0, 1, 1);
3770 /* This call returns a big structure. */
3771 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3775 tfom = void_type_node;
3777 /* ??? Unfinished: must pass the memory address as an argument. */
3779 /* Copy all the libcall-arguments out of the varargs data
3780 and into a vector ARGVEC.
3782 Compute how to pass each argument. We only support a very small subset
3783 of the full argument passing conventions to limit complexity here since
3784 library functions shouldn't have many args. */
3786 argvec = alloca ((nargs + 1) * sizeof (struct arg));
3787 memset (argvec, 0, (nargs + 1) * sizeof (struct arg));
3789 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3790 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far, outmode, fun);
3792 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0, nargs);
3795 args_size.constant = 0;
3800 /* Now we are about to start emitting insns that can be deleted
3801 if a libcall is deleted. */
3802 if (flags & ECF_LIBCALL_BLOCK)
3807 /* If there's a structure value address to be passed,
3808 either pass it in the special place, or pass it as an extra argument. */
3809 if (mem_value && struct_value == 0 && ! pcc_struct_value)
3811 rtx addr = XEXP (mem_value, 0);
3814 /* Make sure it is a reasonable operand for a move or push insn. */
3815 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3816 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3817 addr = force_operand (addr, NULL_RTX);
3819 argvec[count].value = addr;
3820 argvec[count].mode = Pmode;
3821 argvec[count].partial = 0;
3823 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3824 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3825 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3829 locate_and_pad_parm (Pmode, NULL_TREE,
3830 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3833 argvec[count].reg != 0,
3835 0, NULL_TREE, &args_size, &argvec[count].locate);
3837 if (argvec[count].reg == 0 || argvec[count].partial != 0
3838 || reg_parm_stack_space > 0)
3839 args_size.constant += argvec[count].locate.size.constant;
3841 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3846 for (; count < nargs; count++)
3848 rtx val = va_arg (p, rtx);
3849 enum machine_mode mode = va_arg (p, enum machine_mode);
3851 /* We cannot convert the arg value to the mode the library wants here;
3852 must do it earlier where we know the signedness of the arg. */
3854 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3857 /* There's no need to call protect_from_queue, because
3858 either emit_move_insn or emit_push_insn will do that. */
3860 /* Make sure it is a reasonable operand for a move or push insn. */
3861 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3862 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3863 val = force_operand (val, NULL_RTX);
3865 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3866 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3870 #ifdef FUNCTION_ARG_CALLEE_COPIES
3871 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far, mode,
3876 /* loop.c won't look at CALL_INSN_FUNCTION_USAGE of const/pure
3877 functions, so we have to pretend this isn't such a function. */
3878 if (flags & ECF_LIBCALL_BLOCK)
3880 rtx insns = get_insns ();
3884 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3886 /* If this was a CONST function, it is now PURE since
3887 it now reads memory. */
3888 if (flags & ECF_CONST)
3890 flags &= ~ECF_CONST;
3894 if (GET_MODE (val) == MEM && ! must_copy)
3898 slot = assign_temp (lang_hooks.types.type_for_mode (mode, 0),
3900 emit_move_insn (slot, val);
3904 tree type = lang_hooks.types.type_for_mode (mode, 0);
3907 = gen_rtx_MEM (mode,
3908 expand_expr (build1 (ADDR_EXPR,
3909 build_pointer_type (type),
3910 make_tree (type, val)),
3911 NULL_RTX, VOIDmode, 0));
3914 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3915 gen_rtx_USE (VOIDmode, slot),
3918 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3919 gen_rtx_CLOBBER (VOIDmode,
3924 val = force_operand (XEXP (slot, 0), NULL_RTX);
3928 argvec[count].value = val;
3929 argvec[count].mode = mode;
3931 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3933 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3934 argvec[count].partial
3935 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3937 argvec[count].partial = 0;
3940 locate_and_pad_parm (mode, NULL_TREE,
3941 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3944 argvec[count].reg != 0,
3946 argvec[count].partial,
3947 NULL_TREE, &args_size, &argvec[count].locate);
3949 if (argvec[count].locate.size.var)
3952 if (argvec[count].reg == 0 || argvec[count].partial != 0
3953 || reg_parm_stack_space > 0)
3954 args_size.constant += argvec[count].locate.size.constant;
3956 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3959 /* If this machine requires an external definition for library
3960 functions, write one out. */
3961 assemble_external_libcall (fun);
3963 original_args_size = args_size;
3964 args_size.constant = (((args_size.constant
3965 + stack_pointer_delta
3969 - stack_pointer_delta);
3971 args_size.constant = MAX (args_size.constant,
3972 reg_parm_stack_space);
3974 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3975 args_size.constant -= reg_parm_stack_space;
3978 if (args_size.constant > current_function_outgoing_args_size)
3979 current_function_outgoing_args_size = args_size.constant;
3981 if (ACCUMULATE_OUTGOING_ARGS)
3983 /* Since the stack pointer will never be pushed, it is possible for
3984 the evaluation of a parm to clobber something we have already
3985 written to the stack. Since most function calls on RISC machines
3986 do not use the stack, this is uncommon, but must work correctly.
3988 Therefore, we save any area of the stack that was already written
3989 and that we are using. Here we set up to do this by making a new
3990 stack usage map from the old one.
3992 Another approach might be to try to reorder the argument
3993 evaluations to avoid this conflicting stack usage. */
3995 needed = args_size.constant;
3997 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3998 /* Since we will be writing into the entire argument area, the
3999 map must be allocated for its entire size, not just the part that
4000 is the responsibility of the caller. */
4001 needed += reg_parm_stack_space;
4004 #ifdef ARGS_GROW_DOWNWARD
4005 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
4008 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
4011 stack_usage_map = alloca (highest_outgoing_arg_in_use);
4013 if (initial_highest_arg_in_use)
4014 memcpy (stack_usage_map, initial_stack_usage_map,
4015 initial_highest_arg_in_use);
4017 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
4018 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
4019 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
4022 /* We must be careful to use virtual regs before they're instantiated,
4023 and real regs afterwards. Loop optimization, for example, can create
4024 new libcalls after we've instantiated the virtual regs, and if we
4025 use virtuals anyway, they won't match the rtl patterns. */
4027 if (virtuals_instantiated)
4028 argblock = plus_constant (stack_pointer_rtx, STACK_POINTER_OFFSET);
4030 argblock = virtual_outgoing_args_rtx;
4035 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
4038 /* If we push args individually in reverse order, perform stack alignment
4039 before the first push (the last arg). */
4040 if (argblock == 0 && PUSH_ARGS_REVERSED)
4041 anti_adjust_stack (GEN_INT (args_size.constant
4042 - original_args_size.constant));
4044 if (PUSH_ARGS_REVERSED)
4055 #ifdef REG_PARM_STACK_SPACE
4056 if (ACCUMULATE_OUTGOING_ARGS)
4058 /* The argument list is the property of the called routine and it
4059 may clobber it. If the fixed area has been used for previous
4060 parameters, we must save and restore it. */
4061 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
4062 &low_to_save, &high_to_save);
4066 /* Push the args that need to be pushed. */
4068 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4069 are to be pushed. */
4070 for (count = 0; count < nargs; count++, argnum += inc)
4072 enum machine_mode mode = argvec[argnum].mode;
4073 rtx val = argvec[argnum].value;
4074 rtx reg = argvec[argnum].reg;
4075 int partial = argvec[argnum].partial;
4076 int lower_bound = 0, upper_bound = 0, i;
4078 if (! (reg != 0 && partial == 0))
4080 if (ACCUMULATE_OUTGOING_ARGS)
4082 /* If this is being stored into a pre-allocated, fixed-size,
4083 stack area, save any previous data at that location. */
4085 #ifdef ARGS_GROW_DOWNWARD
4086 /* stack_slot is negative, but we want to index stack_usage_map
4087 with positive values. */
4088 upper_bound = -argvec[argnum].locate.offset.constant + 1;
4089 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
4091 lower_bound = argvec[argnum].locate.offset.constant;
4092 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
4096 /* Don't worry about things in the fixed argument area;
4097 it has already been saved. */
4098 if (i < reg_parm_stack_space)
4099 i = reg_parm_stack_space;
4100 while (i < upper_bound && stack_usage_map[i] == 0)
4103 if (i < upper_bound)
4105 /* We need to make a save area. */
4107 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
4108 enum machine_mode save_mode
4109 = mode_for_size (size, MODE_INT, 1);
4111 = plus_constant (argblock,
4112 argvec[argnum].locate.offset.constant);
4114 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
4116 if (save_mode == BLKmode)
4118 argvec[argnum].save_area
4119 = assign_stack_temp (BLKmode,
4120 argvec[argnum].locate.size.constant,
4123 emit_block_move (validize_mem (argvec[argnum].save_area),
4125 GEN_INT (argvec[argnum].locate.size.constant),
4126 BLOCK_OP_CALL_PARM);
4130 argvec[argnum].save_area = gen_reg_rtx (save_mode);
4132 emit_move_insn (argvec[argnum].save_area, stack_area);
4137 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, PARM_BOUNDARY,
4138 partial, reg, 0, argblock,
4139 GEN_INT (argvec[argnum].locate.offset.constant),
4140 reg_parm_stack_space,
4141 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad));
4143 /* Now mark the segment we just used. */
4144 if (ACCUMULATE_OUTGOING_ARGS)
4145 for (i = lower_bound; i < upper_bound; i++)
4146 stack_usage_map[i] = 1;
4152 /* If we pushed args in forward order, perform stack alignment
4153 after pushing the last arg. */
4154 if (argblock == 0 && !PUSH_ARGS_REVERSED)
4155 anti_adjust_stack (GEN_INT (args_size.constant
4156 - original_args_size.constant));
4158 if (PUSH_ARGS_REVERSED)
4163 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0, 0);
4165 /* Now load any reg parms into their regs. */
4167 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4168 are to be pushed. */
4169 for (count = 0; count < nargs; count++, argnum += inc)
4171 rtx val = argvec[argnum].value;
4172 rtx reg = argvec[argnum].reg;
4173 int partial = argvec[argnum].partial;
4175 /* Handle calls that pass values in multiple non-contiguous
4176 locations. The PA64 has examples of this for library calls. */
4177 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4178 emit_group_load (reg, val, NULL_TREE, GET_MODE_SIZE (GET_MODE (val)));
4179 else if (reg != 0 && partial == 0)
4180 emit_move_insn (reg, val);
4185 /* Any regs containing parms remain in use through the call. */
4186 for (count = 0; count < nargs; count++)
4188 rtx reg = argvec[count].reg;
4189 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4190 use_group_regs (&call_fusage, reg);
4192 use_reg (&call_fusage, reg);
4195 /* Pass the function the address in which to return a structure value. */
4196 if (mem_value != 0 && struct_value != 0 && ! pcc_struct_value)
4198 emit_move_insn (struct_value,
4200 force_operand (XEXP (mem_value, 0),
4202 if (GET_CODE (struct_value) == REG)
4203 use_reg (&call_fusage, struct_value);
4206 /* Don't allow popping to be deferred, since then
4207 cse'ing of library calls could delete a call and leave the pop. */
4209 valreg = (mem_value == 0 && outmode != VOIDmode
4210 ? hard_libcall_value (outmode) : NULL_RTX);
4212 /* Stack must be properly aligned now. */
4213 if (stack_pointer_delta & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1))
4216 before_call = get_last_insn ();
4218 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4219 will set inhibit_defer_pop to that value. */
4220 /* The return type is needed to decide how many bytes the function pops.
4221 Signedness plays no role in that, so for simplicity, we pretend it's
4222 always signed. We also assume that the list of arguments passed has
4223 no impact, so we pretend it is unknown. */
4226 get_identifier (XSTR (orgfun, 0)),
4227 build_function_type (tfom, NULL_TREE),
4228 original_args_size.constant, args_size.constant,
4230 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
4232 old_inhibit_defer_pop + 1, call_fusage, flags, & args_so_far);
4234 /* For calls to `setjmp', etc., inform flow.c it should complain
4235 if nonvolatile values are live. For functions that cannot return,
4236 inform flow that control does not fall through. */
4238 if (flags & (ECF_NORETURN | ECF_LONGJMP))
4240 /* The barrier note must be emitted
4241 immediately after the CALL_INSN. Some ports emit more than
4242 just a CALL_INSN above, so we must search for it here. */
4244 rtx last = get_last_insn ();
4245 while (GET_CODE (last) != CALL_INSN)
4247 last = PREV_INSN (last);
4248 /* There was no CALL_INSN? */
4249 if (last == before_call)
4253 emit_barrier_after (last);
4256 /* Now restore inhibit_defer_pop to its actual original value. */
4259 /* If call is cse'able, make appropriate pair of reg-notes around it.
4260 Test valreg so we don't crash; may safely ignore `const'
4261 if return type is void. Disable for PARALLEL return values, because
4262 we have no way to move such values into a pseudo register. */
4263 if (flags & ECF_LIBCALL_BLOCK)
4269 insns = get_insns ();
4279 if (GET_CODE (valreg) == PARALLEL)
4281 temp = gen_reg_rtx (outmode);
4282 emit_group_store (temp, valreg, NULL_TREE,
4283 GET_MODE_SIZE (outmode));
4287 temp = gen_reg_rtx (GET_MODE (valreg));
4289 /* Construct an "equal form" for the value which mentions all the
4290 arguments in order as well as the function name. */
4291 for (i = 0; i < nargs; i++)
4292 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
4293 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
4295 insns = get_insns ();
4298 if (flags & ECF_PURE)
4299 note = gen_rtx_EXPR_LIST (VOIDmode,
4300 gen_rtx_USE (VOIDmode,
4301 gen_rtx_MEM (BLKmode,
4302 gen_rtx_SCRATCH (VOIDmode))),
4305 emit_libcall_block (insns, temp, valreg, note);
4312 /* Copy the value to the right place. */
4313 if (outmode != VOIDmode && retval)
4319 if (value != mem_value)
4320 emit_move_insn (value, mem_value);
4322 else if (GET_CODE (valreg) == PARALLEL)
4325 value = gen_reg_rtx (outmode);
4326 emit_group_store (value, valreg, NULL_TREE, GET_MODE_SIZE (outmode));
4328 else if (value != 0)
4329 emit_move_insn (value, valreg);
4334 if (ACCUMULATE_OUTGOING_ARGS)
4336 #ifdef REG_PARM_STACK_SPACE
4338 restore_fixed_argument_area (save_area, argblock,
4339 high_to_save, low_to_save);
4342 /* If we saved any argument areas, restore them. */
4343 for (count = 0; count < nargs; count++)
4344 if (argvec[count].save_area)
4346 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4347 rtx adr = plus_constant (argblock,
4348 argvec[count].locate.offset.constant);
4349 rtx stack_area = gen_rtx_MEM (save_mode,
4350 memory_address (save_mode, adr));
4352 if (save_mode == BLKmode)
4353 emit_block_move (stack_area,
4354 validize_mem (argvec[count].save_area),
4355 GEN_INT (argvec[count].locate.size.constant),
4356 BLOCK_OP_CALL_PARM);
4358 emit_move_insn (stack_area, argvec[count].save_area);
4361 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4362 stack_usage_map = initial_stack_usage_map;
4369 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4370 (emitting the queue unless NO_QUEUE is nonzero),
4371 for a value of mode OUTMODE,
4372 with NARGS different arguments, passed as alternating rtx values
4373 and machine_modes to convert them to.
4374 The rtx values should have been passed through protect_from_queue already.
4376 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4377 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4378 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4379 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4380 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4381 or other LCT_ value for other types of library calls. */
4384 emit_library_call (rtx orgfun, enum libcall_type fn_type,
4385 enum machine_mode outmode, int nargs, ...)
4389 va_start (p, nargs);
4390 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4394 /* Like emit_library_call except that an extra argument, VALUE,
4395 comes second and says where to store the result.
4396 (If VALUE is zero, this function chooses a convenient way
4397 to return the value.
4399 This function returns an rtx for where the value is to be found.
4400 If VALUE is nonzero, VALUE is returned. */
4403 emit_library_call_value (rtx orgfun, rtx value,
4404 enum libcall_type fn_type,
4405 enum machine_mode outmode, int nargs, ...)
4410 va_start (p, nargs);
4411 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4418 /* Store a single argument for a function call
4419 into the register or memory area where it must be passed.
4420 *ARG describes the argument value and where to pass it.
4422 ARGBLOCK is the address of the stack-block for all the arguments,
4423 or 0 on a machine where arguments are pushed individually.
4425 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4426 so must be careful about how the stack is used.
4428 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4429 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4430 that we need not worry about saving and restoring the stack.
4432 FNDECL is the declaration of the function we are calling.
4434 Return nonzero if this arg should cause sibcall failure,
4438 store_one_arg (struct arg_data *arg, rtx argblock, int flags,
4439 int variable_size ATTRIBUTE_UNUSED, int reg_parm_stack_space)
4441 tree pval = arg->tree_value;
4445 int i, lower_bound = 0, upper_bound = 0;
4446 int sibcall_failure = 0;
4448 if (TREE_CODE (pval) == ERROR_MARK)
4451 /* Push a new temporary level for any temporaries we make for
4455 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4457 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4458 save any previous data at that location. */
4459 if (argblock && ! variable_size && arg->stack)
4461 #ifdef ARGS_GROW_DOWNWARD
4462 /* stack_slot is negative, but we want to index stack_usage_map
4463 with positive values. */
4464 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4465 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4469 lower_bound = upper_bound - arg->locate.size.constant;
4471 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4472 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4476 upper_bound = lower_bound + arg->locate.size.constant;
4480 /* Don't worry about things in the fixed argument area;
4481 it has already been saved. */
4482 if (i < reg_parm_stack_space)
4483 i = reg_parm_stack_space;
4484 while (i < upper_bound && stack_usage_map[i] == 0)
4487 if (i < upper_bound)
4489 /* We need to make a save area. */
4490 unsigned int size = arg->locate.size.constant * BITS_PER_UNIT;
4491 enum machine_mode save_mode = mode_for_size (size, MODE_INT, 1);
4492 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
4493 rtx stack_area = gen_rtx_MEM (save_mode, adr);
4495 if (save_mode == BLKmode)
4497 tree ot = TREE_TYPE (arg->tree_value);
4498 tree nt = build_qualified_type (ot, (TYPE_QUALS (ot)
4499 | TYPE_QUAL_CONST));
4501 arg->save_area = assign_temp (nt, 0, 1, 1);
4502 preserve_temp_slots (arg->save_area);
4503 emit_block_move (validize_mem (arg->save_area), stack_area,
4504 expr_size (arg->tree_value),
4505 BLOCK_OP_CALL_PARM);
4509 arg->save_area = gen_reg_rtx (save_mode);
4510 emit_move_insn (arg->save_area, stack_area);
4516 /* If this isn't going to be placed on both the stack and in registers,
4517 set up the register and number of words. */
4518 if (! arg->pass_on_stack)
4520 if (flags & ECF_SIBCALL)
4521 reg = arg->tail_call_reg;
4524 partial = arg->partial;
4527 if (reg != 0 && partial == 0)
4528 /* Being passed entirely in a register. We shouldn't be called in
4532 /* If this arg needs special alignment, don't load the registers
4534 if (arg->n_aligned_regs != 0)
4537 /* If this is being passed partially in a register, we can't evaluate
4538 it directly into its stack slot. Otherwise, we can. */
4539 if (arg->value == 0)
4541 /* stack_arg_under_construction is nonzero if a function argument is
4542 being evaluated directly into the outgoing argument list and
4543 expand_call must take special action to preserve the argument list
4544 if it is called recursively.
4546 For scalar function arguments stack_usage_map is sufficient to
4547 determine which stack slots must be saved and restored. Scalar
4548 arguments in general have pass_on_stack == 0.
4550 If this argument is initialized by a function which takes the
4551 address of the argument (a C++ constructor or a C function
4552 returning a BLKmode structure), then stack_usage_map is
4553 insufficient and expand_call must push the stack around the
4554 function call. Such arguments have pass_on_stack == 1.
4556 Note that it is always safe to set stack_arg_under_construction,
4557 but this generates suboptimal code if set when not needed. */
4559 if (arg->pass_on_stack)
4560 stack_arg_under_construction++;
4562 arg->value = expand_expr (pval,
4564 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4565 ? NULL_RTX : arg->stack,
4566 VOIDmode, EXPAND_STACK_PARM);
4568 /* If we are promoting object (or for any other reason) the mode
4569 doesn't agree, convert the mode. */
4571 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4572 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4573 arg->value, arg->unsignedp);
4575 if (arg->pass_on_stack)
4576 stack_arg_under_construction--;
4579 /* Don't allow anything left on stack from computation
4580 of argument to alloca. */
4581 if (flags & ECF_MAY_BE_ALLOCA)
4582 do_pending_stack_adjust ();
4584 if (arg->value == arg->stack)
4585 /* If the value is already in the stack slot, we are done. */
4587 else if (arg->mode != BLKmode)
4591 /* Argument is a scalar, not entirely passed in registers.
4592 (If part is passed in registers, arg->partial says how much
4593 and emit_push_insn will take care of putting it there.)
4595 Push it, and if its size is less than the
4596 amount of space allocated to it,
4597 also bump stack pointer by the additional space.
4598 Note that in C the default argument promotions
4599 will prevent such mismatches. */
4601 size = GET_MODE_SIZE (arg->mode);
4602 /* Compute how much space the push instruction will push.
4603 On many machines, pushing a byte will advance the stack
4604 pointer by a halfword. */
4605 #ifdef PUSH_ROUNDING
4606 size = PUSH_ROUNDING (size);
4610 /* Compute how much space the argument should get:
4611 round up to a multiple of the alignment for arguments. */
4612 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4613 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4614 / (PARM_BOUNDARY / BITS_PER_UNIT))
4615 * (PARM_BOUNDARY / BITS_PER_UNIT));
4617 /* This isn't already where we want it on the stack, so put it there.
4618 This can either be done with push or copy insns. */
4619 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
4620 PARM_BOUNDARY, partial, reg, used - size, argblock,
4621 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4622 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4624 /* Unless this is a partially-in-register argument, the argument is now
4627 arg->value = arg->stack;
4631 /* BLKmode, at least partly to be pushed. */
4633 unsigned int parm_align;
4637 /* Pushing a nonscalar.
4638 If part is passed in registers, PARTIAL says how much
4639 and emit_push_insn will take care of putting it there. */
4641 /* Round its size up to a multiple
4642 of the allocation unit for arguments. */
4644 if (arg->locate.size.var != 0)
4647 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
4651 /* PUSH_ROUNDING has no effect on us, because
4652 emit_push_insn for BLKmode is careful to avoid it. */
4653 if (reg && GET_CODE (reg) == PARALLEL)
4655 /* Use the size of the elt to compute excess. */
4656 rtx elt = XEXP (XVECEXP (reg, 0, 0), 0);
4657 excess = (arg->locate.size.constant
4658 - int_size_in_bytes (TREE_TYPE (pval))
4659 + partial * GET_MODE_SIZE (GET_MODE (elt)));
4662 excess = (arg->locate.size.constant
4663 - int_size_in_bytes (TREE_TYPE (pval))
4664 + partial * UNITS_PER_WORD);
4665 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
4666 NULL_RTX, TYPE_MODE (sizetype), 0);
4669 /* Some types will require stricter alignment, which will be
4670 provided for elsewhere in argument layout. */
4671 parm_align = MAX (PARM_BOUNDARY, TYPE_ALIGN (TREE_TYPE (pval)));
4673 /* When an argument is padded down, the block is aligned to
4674 PARM_BOUNDARY, but the actual argument isn't. */
4675 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4677 if (arg->locate.size.var)
4678 parm_align = BITS_PER_UNIT;
4681 unsigned int excess_align = (excess & -excess) * BITS_PER_UNIT;
4682 parm_align = MIN (parm_align, excess_align);
4686 if ((flags & ECF_SIBCALL) && GET_CODE (arg->value) == MEM)
4688 /* emit_push_insn might not work properly if arg->value and
4689 argblock + arg->locate.offset areas overlap. */
4693 if (XEXP (x, 0) == current_function_internal_arg_pointer
4694 || (GET_CODE (XEXP (x, 0)) == PLUS
4695 && XEXP (XEXP (x, 0), 0) ==
4696 current_function_internal_arg_pointer
4697 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT))
4699 if (XEXP (x, 0) != current_function_internal_arg_pointer)
4700 i = INTVAL (XEXP (XEXP (x, 0), 1));
4702 /* expand_call should ensure this. */
4703 if (arg->locate.offset.var || GET_CODE (size_rtx) != CONST_INT)
4706 if (arg->locate.offset.constant > i)
4708 if (arg->locate.offset.constant < i + INTVAL (size_rtx))
4709 sibcall_failure = 1;
4711 else if (arg->locate.offset.constant < i)
4713 if (i < arg->locate.offset.constant + INTVAL (size_rtx))
4714 sibcall_failure = 1;
4719 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4720 parm_align, partial, reg, excess, argblock,
4721 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4722 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4724 /* Unless this is a partially-in-register argument, the argument is now
4727 ??? Unlike the case above, in which we want the actual
4728 address of the data, so that we can load it directly into a
4729 register, here we want the address of the stack slot, so that
4730 it's properly aligned for word-by-word copying or something
4731 like that. It's not clear that this is always correct. */
4733 arg->value = arg->stack_slot;
4736 /* Mark all slots this store used. */
4737 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
4738 && argblock && ! variable_size && arg->stack)
4739 for (i = lower_bound; i < upper_bound; i++)
4740 stack_usage_map[i] = 1;
4742 /* Once we have pushed something, pops can't safely
4743 be deferred during the rest of the arguments. */
4746 /* ANSI doesn't require a sequence point here,
4747 but PCC has one, so this will avoid some problems. */
4750 /* Free any temporary slots made in processing this argument. Show
4751 that we might have taken the address of something and pushed that
4753 preserve_temp_slots (NULL_RTX);
4757 return sibcall_failure;
4760 /* Nonzero if we do not know how to pass TYPE solely in registers.
4761 We cannot do so in the following cases:
4763 - if the type has variable size
4764 - if the type is marked as addressable (it is required to be constructed
4766 - if the padding and mode of the type is such that a copy into a register
4767 would put it into the wrong part of the register.
4769 Which padding can't be supported depends on the byte endianness.
4771 A value in a register is implicitly padded at the most significant end.
4772 On a big-endian machine, that is the lower end in memory.
4773 So a value padded in memory at the upper end can't go in a register.
4774 For a little-endian machine, the reverse is true. */
4777 default_must_pass_in_stack (enum machine_mode mode, tree type)
4782 /* If the type has variable size... */
4783 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4786 /* If the type is marked as addressable (it is required
4787 to be constructed into the stack)... */
4788 if (TREE_ADDRESSABLE (type))
4791 /* If the padding and mode of the type is such that a copy into
4792 a register would put it into the wrong part of the register. */
4794 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
4795 && (FUNCTION_ARG_PADDING (mode, type)
4796 == (BYTES_BIG_ENDIAN ? upward : downward)))