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;
732 if (TREE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
735 if (TREE_THIS_VOLATILE (exp))
736 flags |= ECF_NORETURN;
738 /* Mark if the function returns with the stack pointer depressed. We
739 cannot consider it pure or constant in that case. */
740 if (TREE_CODE (type) == FUNCTION_TYPE && TYPE_RETURNS_STACK_DEPRESSED (type))
742 flags |= ECF_SP_DEPRESSED;
743 flags &= ~(ECF_PURE | ECF_CONST | ECF_LIBCALL_BLOCK);
749 /* Detect flags from a CALL_EXPR. */
752 call_expr_flags (tree t)
755 tree decl = get_callee_fndecl (t);
758 flags = flags_from_decl_or_type (decl);
761 t = TREE_TYPE (TREE_OPERAND (t, 0));
762 if (t && TREE_CODE (t) == POINTER_TYPE)
763 flags = flags_from_decl_or_type (TREE_TYPE (t));
771 /* Precompute all register parameters as described by ARGS, storing values
772 into fields within the ARGS array.
774 NUM_ACTUALS indicates the total number elements in the ARGS array.
776 Set REG_PARM_SEEN if we encounter a register parameter. */
779 precompute_register_parameters (int num_actuals, struct arg_data *args, int *reg_parm_seen)
785 for (i = 0; i < num_actuals; i++)
786 if (args[i].reg != 0 && ! args[i].pass_on_stack)
790 if (args[i].value == 0)
793 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
795 preserve_temp_slots (args[i].value);
798 /* ANSI doesn't require a sequence point here,
799 but PCC has one, so this will avoid some problems. */
803 /* If the value is a non-legitimate constant, force it into a
804 pseudo now. TLS symbols sometimes need a call to resolve. */
805 if (CONSTANT_P (args[i].value)
806 && !LEGITIMATE_CONSTANT_P (args[i].value))
807 args[i].value = force_reg (args[i].mode, args[i].value);
809 /* If we are to promote the function arg to a wider mode,
812 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
814 = convert_modes (args[i].mode,
815 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
816 args[i].value, args[i].unsignedp);
818 /* If the value is expensive, and we are inside an appropriately
819 short loop, put the value into a pseudo and then put the pseudo
822 For small register classes, also do this if this call uses
823 register parameters. This is to avoid reload conflicts while
824 loading the parameters registers. */
826 if ((! (GET_CODE (args[i].value) == REG
827 || (GET_CODE (args[i].value) == SUBREG
828 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
829 && args[i].mode != BLKmode
830 && rtx_cost (args[i].value, SET) > COSTS_N_INSNS (1)
831 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
832 || preserve_subexpressions_p ()))
833 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
837 #ifdef REG_PARM_STACK_SPACE
839 /* The argument list is the property of the called routine and it
840 may clobber it. If the fixed area has been used for previous
841 parameters, we must save and restore it. */
844 save_fixed_argument_area (int reg_parm_stack_space, rtx argblock, int *low_to_save, int *high_to_save)
849 /* Compute the boundary of the area that needs to be saved, if any. */
850 high = reg_parm_stack_space;
851 #ifdef ARGS_GROW_DOWNWARD
854 if (high > highest_outgoing_arg_in_use)
855 high = highest_outgoing_arg_in_use;
857 for (low = 0; low < high; low++)
858 if (stack_usage_map[low] != 0)
861 enum machine_mode save_mode;
866 while (stack_usage_map[--high] == 0)
870 *high_to_save = high;
872 num_to_save = high - low + 1;
873 save_mode = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
875 /* If we don't have the required alignment, must do this
877 if ((low & (MIN (GET_MODE_SIZE (save_mode),
878 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
881 #ifdef ARGS_GROW_DOWNWARD
886 stack_area = gen_rtx_MEM (save_mode,
887 memory_address (save_mode,
888 plus_constant (argblock,
891 set_mem_align (stack_area, PARM_BOUNDARY);
892 if (save_mode == BLKmode)
894 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
895 emit_block_move (validize_mem (save_area), stack_area,
896 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
900 save_area = gen_reg_rtx (save_mode);
901 emit_move_insn (save_area, stack_area);
911 restore_fixed_argument_area (rtx save_area, rtx argblock, int high_to_save, int low_to_save)
913 enum machine_mode save_mode = GET_MODE (save_area);
917 #ifdef ARGS_GROW_DOWNWARD
918 delta = -high_to_save;
922 stack_area = gen_rtx_MEM (save_mode,
923 memory_address (save_mode,
924 plus_constant (argblock, delta)));
925 set_mem_align (stack_area, PARM_BOUNDARY);
927 if (save_mode != BLKmode)
928 emit_move_insn (stack_area, save_area);
930 emit_block_move (stack_area, validize_mem (save_area),
931 GEN_INT (high_to_save - low_to_save + 1),
934 #endif /* REG_PARM_STACK_SPACE */
936 /* If any elements in ARGS refer to parameters that are to be passed in
937 registers, but not in memory, and whose alignment does not permit a
938 direct copy into registers. Copy the values into a group of pseudos
939 which we will later copy into the appropriate hard registers.
941 Pseudos for each unaligned argument will be stored into the array
942 args[argnum].aligned_regs. The caller is responsible for deallocating
943 the aligned_regs array if it is nonzero. */
946 store_unaligned_arguments_into_pseudos (struct arg_data *args, int num_actuals)
950 for (i = 0; i < num_actuals; i++)
951 if (args[i].reg != 0 && ! args[i].pass_on_stack
952 && args[i].mode == BLKmode
953 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
954 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
956 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
957 int nregs = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
958 int endian_correction = 0;
960 args[i].n_aligned_regs = args[i].partial ? args[i].partial : nregs;
961 args[i].aligned_regs = xmalloc (sizeof (rtx) * args[i].n_aligned_regs);
963 /* Structures smaller than a word are normally aligned to the
964 least significant byte. On a BYTES_BIG_ENDIAN machine,
965 this means we must skip the empty high order bytes when
966 calculating the bit offset. */
967 if (bytes < UNITS_PER_WORD
968 #ifdef BLOCK_REG_PADDING
969 && (BLOCK_REG_PADDING (args[i].mode,
970 TREE_TYPE (args[i].tree_value), 1)
976 endian_correction = BITS_PER_WORD - bytes * BITS_PER_UNIT;
978 for (j = 0; j < args[i].n_aligned_regs; j++)
980 rtx reg = gen_reg_rtx (word_mode);
981 rtx word = operand_subword_force (args[i].value, j, BLKmode);
982 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
984 args[i].aligned_regs[j] = reg;
985 word = extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
986 word_mode, word_mode, BITS_PER_WORD);
988 /* There is no need to restrict this code to loading items
989 in TYPE_ALIGN sized hunks. The bitfield instructions can
990 load up entire word sized registers efficiently.
992 ??? This may not be needed anymore.
993 We use to emit a clobber here but that doesn't let later
994 passes optimize the instructions we emit. By storing 0 into
995 the register later passes know the first AND to zero out the
996 bitfield being set in the register is unnecessary. The store
997 of 0 will be deleted as will at least the first AND. */
999 emit_move_insn (reg, const0_rtx);
1001 bytes -= bitsize / BITS_PER_UNIT;
1002 store_bit_field (reg, bitsize, endian_correction, word_mode,
1003 word, BITS_PER_WORD);
1008 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1011 NUM_ACTUALS is the total number of parameters.
1013 N_NAMED_ARGS is the total number of named arguments.
1015 FNDECL is the tree code for the target of this call (if known)
1017 ARGS_SO_FAR holds state needed by the target to know where to place
1020 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1021 for arguments which are passed in registers.
1023 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1024 and may be modified by this routine.
1026 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1027 flags which may may be modified by this routine.
1029 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1030 the thunked-to function. */
1033 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
1034 struct arg_data *args,
1035 struct args_size *args_size,
1036 int n_named_args ATTRIBUTE_UNUSED,
1037 tree actparms, tree fndecl,
1038 CUMULATIVE_ARGS *args_so_far,
1039 int reg_parm_stack_space,
1040 rtx *old_stack_level, int *old_pending_adj,
1041 int *must_preallocate, int *ecf_flags,
1042 bool call_from_thunk_p)
1044 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1047 /* Count arg position in order args appear. */
1053 args_size->constant = 0;
1056 /* In this loop, we consider args in the order they are written.
1057 We fill up ARGS from the front or from the back if necessary
1058 so that in any case the first arg to be pushed ends up at the front. */
1060 if (PUSH_ARGS_REVERSED)
1062 i = num_actuals - 1, inc = -1;
1063 /* In this case, must reverse order of args
1064 so that we compute and push the last arg first. */
1071 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1072 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1074 tree type = TREE_TYPE (TREE_VALUE (p));
1076 enum machine_mode mode;
1078 args[i].tree_value = TREE_VALUE (p);
1080 /* Replace erroneous argument with constant zero. */
1081 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1082 args[i].tree_value = integer_zero_node, type = integer_type_node;
1084 /* If TYPE is a transparent union, pass things the way we would
1085 pass the first field of the union. We have already verified that
1086 the modes are the same. */
1087 if (TREE_CODE (type) == UNION_TYPE && TYPE_TRANSPARENT_UNION (type))
1088 type = TREE_TYPE (TYPE_FIELDS (type));
1090 /* Decide where to pass this arg.
1092 args[i].reg is nonzero if all or part is passed in registers.
1094 args[i].partial is nonzero if part but not all is passed in registers,
1095 and the exact value says how many words are passed in registers.
1097 args[i].pass_on_stack is nonzero if the argument must at least be
1098 computed on the stack. It may then be loaded back into registers
1099 if args[i].reg is nonzero.
1101 These decisions are driven by the FUNCTION_... macros and must agree
1102 with those made by function.c. */
1104 /* See if this argument should be passed by invisible reference. */
1105 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (type))
1106 || TREE_ADDRESSABLE (type)
1107 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1108 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
1109 type, argpos < n_named_args)
1113 /* If we're compiling a thunk, pass through invisible
1114 references instead of making a copy. */
1115 if (call_from_thunk_p
1116 #ifdef FUNCTION_ARG_CALLEE_COPIES
1117 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
1118 type, argpos < n_named_args)
1119 /* If it's in a register, we must make a copy of it too. */
1120 /* ??? Is this a sufficient test? Is there a better one? */
1121 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1122 && REG_P (DECL_RTL (args[i].tree_value)))
1123 && ! TREE_ADDRESSABLE (type))
1127 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1128 new object from the argument. If we are passing by
1129 invisible reference, the callee will do that for us, so we
1130 can strip off the TARGET_EXPR. This is not always safe,
1131 but it is safe in the only case where this is a useful
1132 optimization; namely, when the argument is a plain object.
1133 In that case, the frontend is just asking the backend to
1134 make a bitwise copy of the argument. */
1136 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
1137 && (DECL_P (TREE_OPERAND (args[i].tree_value, 1)))
1138 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
1139 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
1141 args[i].tree_value = build1 (ADDR_EXPR,
1142 build_pointer_type (type),
1143 args[i].tree_value);
1144 type = build_pointer_type (type);
1146 else if (TREE_CODE (args[i].tree_value) == TARGET_EXPR)
1148 /* In the V3 C++ ABI, parameters are destroyed in the caller.
1149 We implement this by passing the address of the temporary
1150 rather than expanding it into another allocated slot. */
1151 args[i].tree_value = build1 (ADDR_EXPR,
1152 build_pointer_type (type),
1153 args[i].tree_value);
1154 type = build_pointer_type (type);
1158 /* We make a copy of the object and pass the address to the
1159 function being called. */
1162 if (!COMPLETE_TYPE_P (type)
1163 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1164 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1165 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1166 STACK_CHECK_MAX_VAR_SIZE))))
1168 /* This is a variable-sized object. Make space on the stack
1170 rtx size_rtx = expr_size (TREE_VALUE (p));
1172 if (*old_stack_level == 0)
1174 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1175 *old_pending_adj = pending_stack_adjust;
1176 pending_stack_adjust = 0;
1179 copy = gen_rtx_MEM (BLKmode,
1180 allocate_dynamic_stack_space
1181 (size_rtx, NULL_RTX, TYPE_ALIGN (type)));
1182 set_mem_attributes (copy, type, 1);
1185 copy = assign_temp (type, 0, 1, 0);
1187 store_expr (args[i].tree_value, copy, 0);
1188 *ecf_flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
1190 args[i].tree_value = build1 (ADDR_EXPR,
1191 build_pointer_type (type),
1192 make_tree (type, copy));
1193 type = build_pointer_type (type);
1197 mode = TYPE_MODE (type);
1198 unsignedp = TREE_UNSIGNED (type);
1200 if (targetm.calls.promote_function_args (fndecl ? TREE_TYPE (fndecl) : 0))
1201 mode = promote_mode (type, mode, &unsignedp, 1);
1203 args[i].unsignedp = unsignedp;
1204 args[i].mode = mode;
1206 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1207 argpos < n_named_args);
1208 #ifdef FUNCTION_INCOMING_ARG
1209 /* If this is a sibling call and the machine has register windows, the
1210 register window has to be unwinded before calling the routine, so
1211 arguments have to go into the incoming registers. */
1212 args[i].tail_call_reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1213 argpos < n_named_args);
1215 args[i].tail_call_reg = args[i].reg;
1218 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1221 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1222 argpos < n_named_args);
1225 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1227 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1228 it means that we are to pass this arg in the register(s) designated
1229 by the PARALLEL, but also to pass it in the stack. */
1230 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1231 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1232 args[i].pass_on_stack = 1;
1234 /* If this is an addressable type, we must preallocate the stack
1235 since we must evaluate the object into its final location.
1237 If this is to be passed in both registers and the stack, it is simpler
1239 if (TREE_ADDRESSABLE (type)
1240 || (args[i].pass_on_stack && args[i].reg != 0))
1241 *must_preallocate = 1;
1243 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1244 we cannot consider this function call constant. */
1245 if (TREE_ADDRESSABLE (type))
1246 *ecf_flags &= ~ECF_LIBCALL_BLOCK;
1248 /* Compute the stack-size of this argument. */
1249 if (args[i].reg == 0 || args[i].partial != 0
1250 || reg_parm_stack_space > 0
1251 || args[i].pass_on_stack)
1252 locate_and_pad_parm (mode, type,
1253 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1258 args[i].pass_on_stack ? 0 : args[i].partial,
1259 fndecl, args_size, &args[i].locate);
1260 #ifdef BLOCK_REG_PADDING
1262 /* The argument is passed entirely in registers. See at which
1263 end it should be padded. */
1264 args[i].locate.where_pad =
1265 BLOCK_REG_PADDING (mode, type,
1266 int_size_in_bytes (type) <= UNITS_PER_WORD);
1269 /* Update ARGS_SIZE, the total stack space for args so far. */
1271 args_size->constant += args[i].locate.size.constant;
1272 if (args[i].locate.size.var)
1273 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
1275 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1276 have been used, etc. */
1278 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1279 argpos < n_named_args);
1283 /* Update ARGS_SIZE to contain the total size for the argument block.
1284 Return the original constant component of the argument block's size.
1286 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1287 for arguments passed in registers. */
1290 compute_argument_block_size (int reg_parm_stack_space,
1291 struct args_size *args_size,
1292 int preferred_stack_boundary ATTRIBUTE_UNUSED)
1294 int unadjusted_args_size = args_size->constant;
1296 /* For accumulate outgoing args mode we don't need to align, since the frame
1297 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1298 backends from generating misaligned frame sizes. */
1299 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1300 preferred_stack_boundary = STACK_BOUNDARY;
1302 /* Compute the actual size of the argument block required. The variable
1303 and constant sizes must be combined, the size may have to be rounded,
1304 and there may be a minimum required size. */
1308 args_size->var = ARGS_SIZE_TREE (*args_size);
1309 args_size->constant = 0;
1311 preferred_stack_boundary /= BITS_PER_UNIT;
1312 if (preferred_stack_boundary > 1)
1314 /* We don't handle this case yet. To handle it correctly we have
1315 to add the delta, round and subtract the delta.
1316 Currently no machine description requires this support. */
1317 if (stack_pointer_delta & (preferred_stack_boundary - 1))
1319 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1322 if (reg_parm_stack_space > 0)
1325 = size_binop (MAX_EXPR, args_size->var,
1326 ssize_int (reg_parm_stack_space));
1328 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1329 /* The area corresponding to register parameters is not to count in
1330 the size of the block we need. So make the adjustment. */
1332 = size_binop (MINUS_EXPR, args_size->var,
1333 ssize_int (reg_parm_stack_space));
1339 preferred_stack_boundary /= BITS_PER_UNIT;
1340 if (preferred_stack_boundary < 1)
1341 preferred_stack_boundary = 1;
1342 args_size->constant = (((args_size->constant
1343 + stack_pointer_delta
1344 + preferred_stack_boundary - 1)
1345 / preferred_stack_boundary
1346 * preferred_stack_boundary)
1347 - stack_pointer_delta);
1349 args_size->constant = MAX (args_size->constant,
1350 reg_parm_stack_space);
1352 #ifdef MAYBE_REG_PARM_STACK_SPACE
1353 if (reg_parm_stack_space == 0)
1354 args_size->constant = 0;
1357 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1358 args_size->constant -= reg_parm_stack_space;
1361 return unadjusted_args_size;
1364 /* Precompute parameters as needed for a function call.
1366 FLAGS is mask of ECF_* constants.
1368 NUM_ACTUALS is the number of arguments.
1370 ARGS is an array containing information for each argument; this
1371 routine fills in the INITIAL_VALUE and VALUE fields for each
1372 precomputed argument. */
1375 precompute_arguments (int flags, int num_actuals, struct arg_data *args)
1379 /* If this function call is cse'able, precompute all the parameters.
1380 Note that if the parameter is constructed into a temporary, this will
1381 cause an additional copy because the parameter will be constructed
1382 into a temporary location and then copied into the outgoing arguments.
1383 If a parameter contains a call to alloca and this function uses the
1384 stack, precompute the parameter. */
1386 /* If we preallocated the stack space, and some arguments must be passed
1387 on the stack, then we must precompute any parameter which contains a
1388 function call which will store arguments on the stack.
1389 Otherwise, evaluating the parameter may clobber previous parameters
1390 which have already been stored into the stack. (we have code to avoid
1391 such case by saving the outgoing stack arguments, but it results in
1394 for (i = 0; i < num_actuals; i++)
1395 if ((flags & ECF_LIBCALL_BLOCK)
1396 || calls_function (args[i].tree_value, !ACCUMULATE_OUTGOING_ARGS))
1398 enum machine_mode mode;
1400 /* If this is an addressable type, we cannot pre-evaluate it. */
1401 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1405 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1407 /* ANSI doesn't require a sequence point here,
1408 but PCC has one, so this will avoid some problems. */
1411 args[i].initial_value = args[i].value
1412 = protect_from_queue (args[i].value, 0);
1414 mode = TYPE_MODE (TREE_TYPE (args[i].tree_value));
1415 if (mode != args[i].mode)
1418 = convert_modes (args[i].mode, mode,
1419 args[i].value, args[i].unsignedp);
1420 #ifdef PROMOTE_FOR_CALL_ONLY
1421 /* CSE will replace this only if it contains args[i].value
1422 pseudo, so convert it down to the declared mode using
1424 if (GET_CODE (args[i].value) == REG
1425 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1427 args[i].initial_value
1428 = gen_lowpart_SUBREG (mode, args[i].value);
1429 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1430 SUBREG_PROMOTED_UNSIGNED_SET (args[i].initial_value,
1438 /* Given the current state of MUST_PREALLOCATE and information about
1439 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1440 compute and return the final value for MUST_PREALLOCATE. */
1443 finalize_must_preallocate (int must_preallocate, int num_actuals, struct arg_data *args, struct args_size *args_size)
1445 /* See if we have or want to preallocate stack space.
1447 If we would have to push a partially-in-regs parm
1448 before other stack parms, preallocate stack space instead.
1450 If the size of some parm is not a multiple of the required stack
1451 alignment, we must preallocate.
1453 If the total size of arguments that would otherwise create a copy in
1454 a temporary (such as a CALL) is more than half the total argument list
1455 size, preallocation is faster.
1457 Another reason to preallocate is if we have a machine (like the m88k)
1458 where stack alignment is required to be maintained between every
1459 pair of insns, not just when the call is made. However, we assume here
1460 that such machines either do not have push insns (and hence preallocation
1461 would occur anyway) or the problem is taken care of with
1464 if (! must_preallocate)
1466 int partial_seen = 0;
1467 int copy_to_evaluate_size = 0;
1470 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1472 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1474 else if (partial_seen && args[i].reg == 0)
1475 must_preallocate = 1;
1477 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1478 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1479 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1480 || TREE_CODE (args[i].tree_value) == COND_EXPR
1481 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1482 copy_to_evaluate_size
1483 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1486 if (copy_to_evaluate_size * 2 >= args_size->constant
1487 && args_size->constant > 0)
1488 must_preallocate = 1;
1490 return must_preallocate;
1493 /* If we preallocated stack space, compute the address of each argument
1494 and store it into the ARGS array.
1496 We need not ensure it is a valid memory address here; it will be
1497 validized when it is used.
1499 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1502 compute_argument_addresses (struct arg_data *args, rtx argblock, int num_actuals)
1506 rtx arg_reg = argblock;
1507 int i, arg_offset = 0;
1509 if (GET_CODE (argblock) == PLUS)
1510 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1512 for (i = 0; i < num_actuals; i++)
1514 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
1515 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
1518 /* Skip this parm if it will not be passed on the stack. */
1519 if (! args[i].pass_on_stack && args[i].reg != 0)
1522 if (GET_CODE (offset) == CONST_INT)
1523 addr = plus_constant (arg_reg, INTVAL (offset));
1525 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1527 addr = plus_constant (addr, arg_offset);
1528 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1529 set_mem_align (args[i].stack, PARM_BOUNDARY);
1530 set_mem_attributes (args[i].stack,
1531 TREE_TYPE (args[i].tree_value), 1);
1533 if (GET_CODE (slot_offset) == CONST_INT)
1534 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1536 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1538 addr = plus_constant (addr, arg_offset);
1539 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1540 set_mem_align (args[i].stack_slot, PARM_BOUNDARY);
1541 set_mem_attributes (args[i].stack_slot,
1542 TREE_TYPE (args[i].tree_value), 1);
1544 /* Function incoming arguments may overlap with sibling call
1545 outgoing arguments and we cannot allow reordering of reads
1546 from function arguments with stores to outgoing arguments
1547 of sibling calls. */
1548 set_mem_alias_set (args[i].stack, 0);
1549 set_mem_alias_set (args[i].stack_slot, 0);
1554 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1555 in a call instruction.
1557 FNDECL is the tree node for the target function. For an indirect call
1558 FNDECL will be NULL_TREE.
1560 ADDR is the operand 0 of CALL_EXPR for this call. */
1563 rtx_for_function_call (tree fndecl, tree addr)
1567 /* Get the function to call, in the form of RTL. */
1570 /* If this is the first use of the function, see if we need to
1571 make an external definition for it. */
1572 if (! TREE_USED (fndecl))
1574 assemble_external (fndecl);
1575 TREE_USED (fndecl) = 1;
1578 /* Get a SYMBOL_REF rtx for the function address. */
1579 funexp = XEXP (DECL_RTL (fndecl), 0);
1582 /* Generate an rtx (probably a pseudo-register) for the address. */
1585 funexp = expand_expr (addr, NULL_RTX, VOIDmode, 0);
1586 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1592 /* Do the register loads required for any wholly-register parms or any
1593 parms which are passed both on the stack and in a register. Their
1594 expressions were already evaluated.
1596 Mark all register-parms as living through the call, putting these USE
1597 insns in the CALL_INSN_FUNCTION_USAGE field.
1599 When IS_SIBCALL, perform the check_sibcall_overlap_argument_overlap
1600 checking, setting *SIBCALL_FAILURE if appropriate. */
1603 load_register_parameters (struct arg_data *args, int num_actuals,
1604 rtx *call_fusage, int flags, int is_sibcall,
1605 int *sibcall_failure)
1609 for (i = 0; i < num_actuals; i++)
1611 rtx reg = ((flags & ECF_SIBCALL)
1612 ? args[i].tail_call_reg : args[i].reg);
1615 int partial = args[i].partial;
1618 rtx before_arg = get_last_insn ();
1619 /* Set to non-negative if must move a word at a time, even if just
1620 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1621 we just use a normal move insn. This value can be zero if the
1622 argument is a zero size structure with no fields. */
1626 else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
1628 size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1629 nregs = (size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1632 size = GET_MODE_SIZE (args[i].mode);
1634 /* Handle calls that pass values in multiple non-contiguous
1635 locations. The Irix 6 ABI has examples of this. */
1637 if (GET_CODE (reg) == PARALLEL)
1639 tree type = TREE_TYPE (args[i].tree_value);
1640 emit_group_load (reg, args[i].value, type,
1641 int_size_in_bytes (type));
1644 /* If simple case, just do move. If normal partial, store_one_arg
1645 has already loaded the register for us. In all other cases,
1646 load the register(s) from memory. */
1648 else if (nregs == -1)
1650 emit_move_insn (reg, args[i].value);
1651 #ifdef BLOCK_REG_PADDING
1652 /* Handle case where we have a value that needs shifting
1653 up to the msb. eg. a QImode value and we're padding
1654 upward on a BYTES_BIG_ENDIAN machine. */
1655 if (size < UNITS_PER_WORD
1656 && (args[i].locate.where_pad
1657 == (BYTES_BIG_ENDIAN ? upward : downward)))
1660 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
1662 /* Assigning REG here rather than a temp makes CALL_FUSAGE
1663 report the whole reg as used. Strictly speaking, the
1664 call only uses SIZE bytes at the msb end, but it doesn't
1665 seem worth generating rtl to say that. */
1666 reg = gen_rtx_REG (word_mode, REGNO (reg));
1667 x = expand_binop (word_mode, ashl_optab, reg,
1668 GEN_INT (shift), reg, 1, OPTAB_WIDEN);
1670 emit_move_insn (reg, x);
1675 /* If we have pre-computed the values to put in the registers in
1676 the case of non-aligned structures, copy them in now. */
1678 else if (args[i].n_aligned_regs != 0)
1679 for (j = 0; j < args[i].n_aligned_regs; j++)
1680 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1681 args[i].aligned_regs[j]);
1683 else if (partial == 0 || args[i].pass_on_stack)
1685 rtx mem = validize_mem (args[i].value);
1687 #ifdef BLOCK_REG_PADDING
1688 /* Handle a BLKmode that needs shifting. */
1689 if (nregs == 1 && size < UNITS_PER_WORD
1690 && args[i].locate.where_pad == downward)
1692 rtx tem = operand_subword_force (mem, 0, args[i].mode);
1693 rtx ri = gen_rtx_REG (word_mode, REGNO (reg));
1694 rtx x = gen_reg_rtx (word_mode);
1695 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
1696 optab dir = BYTES_BIG_ENDIAN ? lshr_optab : ashl_optab;
1698 emit_move_insn (x, tem);
1699 x = expand_binop (word_mode, dir, x, GEN_INT (shift),
1700 ri, 1, OPTAB_WIDEN);
1702 emit_move_insn (ri, x);
1706 move_block_to_reg (REGNO (reg), mem, nregs, args[i].mode);
1709 /* When a parameter is a block, and perhaps in other cases, it is
1710 possible that it did a load from an argument slot that was
1711 already clobbered. */
1713 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
1714 *sibcall_failure = 1;
1716 /* Handle calls that pass values in multiple non-contiguous
1717 locations. The Irix 6 ABI has examples of this. */
1718 if (GET_CODE (reg) == PARALLEL)
1719 use_group_regs (call_fusage, reg);
1720 else if (nregs == -1)
1721 use_reg (call_fusage, reg);
1723 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1728 /* Try to integrate function. See expand_inline_function for documentation
1729 about the parameters. */
1732 try_to_integrate (tree fndecl, tree actparms, rtx target, int ignore,
1733 tree type, rtx structure_value_addr)
1738 rtx old_stack_level = 0;
1739 int reg_parm_stack_space = 0;
1741 #ifdef REG_PARM_STACK_SPACE
1742 #ifdef MAYBE_REG_PARM_STACK_SPACE
1743 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1745 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1749 before_call = get_last_insn ();
1751 timevar_push (TV_INTEGRATION);
1753 temp = expand_inline_function (fndecl, actparms, target,
1755 structure_value_addr);
1757 timevar_pop (TV_INTEGRATION);
1759 /* If inlining succeeded, return. */
1760 if (temp != (rtx) (size_t) - 1)
1762 if (ACCUMULATE_OUTGOING_ARGS)
1764 /* If the outgoing argument list must be preserved, push
1765 the stack before executing the inlined function if it
1768 i = reg_parm_stack_space;
1769 if (i > highest_outgoing_arg_in_use)
1770 i = highest_outgoing_arg_in_use;
1771 while (--i >= 0 && stack_usage_map[i] == 0)
1774 if (stack_arg_under_construction || i >= 0)
1777 = before_call ? NEXT_INSN (before_call) : get_insns ();
1778 rtx insn = NULL_RTX, seq;
1780 /* Look for a call in the inline function code.
1781 If DECL_STRUCT_FUNCTION (fndecl)->outgoing_args_size is
1782 nonzero then there is a call and it is not necessary
1783 to scan the insns. */
1785 if (DECL_STRUCT_FUNCTION (fndecl)->outgoing_args_size == 0)
1786 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1787 if (GET_CODE (insn) == CALL_INSN)
1792 /* Reserve enough stack space so that the largest
1793 argument list of any function call in the inline
1794 function does not overlap the argument list being
1795 evaluated. This is usually an overestimate because
1796 allocate_dynamic_stack_space reserves space for an
1797 outgoing argument list in addition to the requested
1798 space, but there is no way to ask for stack space such
1799 that an argument list of a certain length can be
1802 Add the stack space reserved for register arguments, if
1803 any, in the inline function. What is really needed is the
1804 largest value of reg_parm_stack_space in the inline
1805 function, but that is not available. Using the current
1806 value of reg_parm_stack_space is wrong, but gives
1807 correct results on all supported machines. */
1810 (DECL_STRUCT_FUNCTION (fndecl)->outgoing_args_size
1811 + reg_parm_stack_space);
1814 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1815 allocate_dynamic_stack_space (GEN_INT (adjust),
1816 NULL_RTX, BITS_PER_UNIT);
1819 emit_insn_before (seq, first_insn);
1820 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1825 /* If the result is equivalent to TARGET, return TARGET to simplify
1826 checks in store_expr. They can be equivalent but not equal in the
1827 case of a function that returns BLKmode. */
1828 if (temp != target && rtx_equal_p (temp, target))
1833 /* If inlining failed, mark FNDECL as needing to be compiled
1834 separately after all. If function was declared inline,
1836 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1837 && optimize > 0 && !TREE_ADDRESSABLE (fndecl))
1839 warning ("%Jinlining failed in call to '%F'", fndecl, fndecl);
1840 warning ("called from here");
1842 (*lang_hooks.mark_addressable) (fndecl);
1843 return (rtx) (size_t) - 1;
1846 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1847 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1848 bytes, then we would need to push some additional bytes to pad the
1849 arguments. So, we compute an adjust to the stack pointer for an
1850 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1851 bytes. Then, when the arguments are pushed the stack will be perfectly
1852 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1853 be popped after the call. Returns the adjustment. */
1856 combine_pending_stack_adjustment_and_call (int unadjusted_args_size,
1857 struct args_size *args_size,
1858 int preferred_unit_stack_boundary)
1860 /* The number of bytes to pop so that the stack will be
1861 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1862 HOST_WIDE_INT adjustment;
1863 /* The alignment of the stack after the arguments are pushed, if we
1864 just pushed the arguments without adjust the stack here. */
1865 HOST_WIDE_INT unadjusted_alignment;
1867 unadjusted_alignment
1868 = ((stack_pointer_delta + unadjusted_args_size)
1869 % preferred_unit_stack_boundary);
1871 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1872 as possible -- leaving just enough left to cancel out the
1873 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1874 PENDING_STACK_ADJUST is non-negative, and congruent to
1875 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1877 /* Begin by trying to pop all the bytes. */
1878 unadjusted_alignment
1879 = (unadjusted_alignment
1880 - (pending_stack_adjust % preferred_unit_stack_boundary));
1881 adjustment = pending_stack_adjust;
1882 /* Push enough additional bytes that the stack will be aligned
1883 after the arguments are pushed. */
1884 if (preferred_unit_stack_boundary > 1)
1886 if (unadjusted_alignment > 0)
1887 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1889 adjustment += unadjusted_alignment;
1892 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1893 bytes after the call. The right number is the entire
1894 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1895 by the arguments in the first place. */
1897 = pending_stack_adjust - adjustment + unadjusted_args_size;
1902 /* Scan X expression if it does not dereference any argument slots
1903 we already clobbered by tail call arguments (as noted in stored_args_map
1905 Return nonzero if X expression dereferences such argument slots,
1909 check_sibcall_argument_overlap_1 (rtx x)
1919 code = GET_CODE (x);
1923 if (XEXP (x, 0) == current_function_internal_arg_pointer)
1925 else if (GET_CODE (XEXP (x, 0)) == PLUS
1926 && XEXP (XEXP (x, 0), 0) ==
1927 current_function_internal_arg_pointer
1928 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
1929 i = INTVAL (XEXP (XEXP (x, 0), 1));
1933 #ifdef ARGS_GROW_DOWNWARD
1934 i = -i - GET_MODE_SIZE (GET_MODE (x));
1937 for (k = 0; k < GET_MODE_SIZE (GET_MODE (x)); k++)
1938 if (i + k < stored_args_map->n_bits
1939 && TEST_BIT (stored_args_map, i + k))
1945 /* Scan all subexpressions. */
1946 fmt = GET_RTX_FORMAT (code);
1947 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
1951 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
1954 else if (*fmt == 'E')
1956 for (j = 0; j < XVECLEN (x, i); j++)
1957 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
1964 /* Scan sequence after INSN if it does not dereference any argument slots
1965 we already clobbered by tail call arguments (as noted in stored_args_map
1966 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
1967 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
1968 should be 0). Return nonzero if sequence after INSN dereferences such argument
1969 slots, zero otherwise. */
1972 check_sibcall_argument_overlap (rtx insn, struct arg_data *arg, int mark_stored_args_map)
1976 if (insn == NULL_RTX)
1977 insn = get_insns ();
1979 insn = NEXT_INSN (insn);
1981 for (; insn; insn = NEXT_INSN (insn))
1983 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
1986 if (mark_stored_args_map)
1988 #ifdef ARGS_GROW_DOWNWARD
1989 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
1991 low = arg->locate.slot_offset.constant;
1994 for (high = low + arg->locate.size.constant; low < high; low++)
1995 SET_BIT (stored_args_map, low);
1997 return insn != NULL_RTX;
2001 fix_unsafe_tree (tree t)
2003 switch (unsafe_for_reeval (t))
2008 case 1: /* Mildly unsafe. */
2009 t = unsave_expr (t);
2012 case 2: /* Wildly unsafe. */
2014 tree var = build_decl (VAR_DECL, NULL_TREE,
2017 expand_expr (t, NULL_RTX, VOIDmode, EXPAND_NORMAL));
2029 /* If function value *VALUE was returned at the most significant end of a
2030 register, shift it towards the least significant end and convert it to
2031 TYPE's mode. Return true and update *VALUE if some action was needed.
2033 TYPE is the type of the function's return value, which is known not
2034 to have mode BLKmode. */
2037 shift_returned_value (tree type, rtx *value)
2039 if (targetm.calls.return_in_msb (type))
2041 HOST_WIDE_INT shift;
2043 shift = (GET_MODE_BITSIZE (GET_MODE (*value))
2044 - BITS_PER_UNIT * int_size_in_bytes (type));
2047 *value = expand_binop (GET_MODE (*value), lshr_optab, *value,
2048 GEN_INT (shift), 0, 1, OPTAB_WIDEN);
2049 *value = convert_to_mode (TYPE_MODE (type), *value, 0);
2056 /* Generate all the code for a function call
2057 and return an rtx for its value.
2058 Store the value in TARGET (specified as an rtx) if convenient.
2059 If the value is stored in TARGET then TARGET is returned.
2060 If IGNORE is nonzero, then we ignore the value of the function call. */
2063 expand_call (tree exp, rtx target, int ignore)
2065 /* Nonzero if we are currently expanding a call. */
2066 static int currently_expanding_call = 0;
2068 /* List of actual parameters. */
2069 tree actparms = TREE_OPERAND (exp, 1);
2070 /* RTX for the function to be called. */
2072 /* Sequence of insns to perform a tail recursive "call". */
2073 rtx tail_recursion_insns = NULL_RTX;
2074 /* Sequence of insns to perform a normal "call". */
2075 rtx normal_call_insns = NULL_RTX;
2076 /* Sequence of insns to perform a tail recursive "call". */
2077 rtx tail_call_insns = NULL_RTX;
2078 /* Data type of the function. */
2080 tree type_arg_types;
2081 /* Declaration of the function being called,
2082 or 0 if the function is computed (not known by name). */
2084 /* The type of the function being called. */
2087 int try_tail_call = 1;
2088 int try_tail_recursion = 1;
2091 /* Register in which non-BLKmode value will be returned,
2092 or 0 if no value or if value is BLKmode. */
2094 /* Address where we should return a BLKmode value;
2095 0 if value not BLKmode. */
2096 rtx structure_value_addr = 0;
2097 /* Nonzero if that address is being passed by treating it as
2098 an extra, implicit first parameter. Otherwise,
2099 it is passed by being copied directly into struct_value_rtx. */
2100 int structure_value_addr_parm = 0;
2101 /* Size of aggregate value wanted, or zero if none wanted
2102 or if we are using the non-reentrant PCC calling convention
2103 or expecting the value in registers. */
2104 HOST_WIDE_INT struct_value_size = 0;
2105 /* Nonzero if called function returns an aggregate in memory PCC style,
2106 by returning the address of where to find it. */
2107 int pcc_struct_value = 0;
2108 rtx struct_value = 0;
2110 /* Number of actual parameters in this call, including struct value addr. */
2112 /* Number of named args. Args after this are anonymous ones
2113 and they must all go on the stack. */
2116 /* Vector of information about each argument.
2117 Arguments are numbered in the order they will be pushed,
2118 not the order they are written. */
2119 struct arg_data *args;
2121 /* Total size in bytes of all the stack-parms scanned so far. */
2122 struct args_size args_size;
2123 struct args_size adjusted_args_size;
2124 /* Size of arguments before any adjustments (such as rounding). */
2125 int unadjusted_args_size;
2126 /* Data on reg parms scanned so far. */
2127 CUMULATIVE_ARGS args_so_far;
2128 /* Nonzero if a reg parm has been scanned. */
2130 /* Nonzero if this is an indirect function call. */
2132 /* Nonzero if we must avoid push-insns in the args for this call.
2133 If stack space is allocated for register parameters, but not by the
2134 caller, then it is preallocated in the fixed part of the stack frame.
2135 So the entire argument block must then be preallocated (i.e., we
2136 ignore PUSH_ROUNDING in that case). */
2138 int must_preallocate = !PUSH_ARGS;
2140 /* Size of the stack reserved for parameter registers. */
2141 int reg_parm_stack_space = 0;
2143 /* Address of space preallocated for stack parms
2144 (on machines that lack push insns), or 0 if space not preallocated. */
2147 /* Mask of ECF_ flags. */
2149 /* Nonzero if this is a call to an inline function. */
2150 int is_integrable = 0;
2151 #ifdef REG_PARM_STACK_SPACE
2152 /* Define the boundary of the register parm stack space that needs to be
2154 int low_to_save, high_to_save;
2155 rtx save_area = 0; /* Place that it is saved */
2158 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2159 rtx temp_target = 0;
2160 char *initial_stack_usage_map = stack_usage_map;
2162 int old_stack_allocated;
2164 /* State variables to track stack modifications. */
2165 rtx old_stack_level = 0;
2166 int old_stack_arg_under_construction = 0;
2167 int old_pending_adj = 0;
2168 int old_inhibit_defer_pop = inhibit_defer_pop;
2170 /* Some stack pointer alterations we make are performed via
2171 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
2172 which we then also need to save/restore along the way. */
2173 int old_stack_pointer_delta = 0;
2176 tree p = TREE_OPERAND (exp, 0);
2177 tree addr = TREE_OPERAND (exp, 0);
2179 /* The alignment of the stack, in bits. */
2180 HOST_WIDE_INT preferred_stack_boundary;
2181 /* The alignment of the stack, in bytes. */
2182 HOST_WIDE_INT preferred_unit_stack_boundary;
2184 /* See if this is "nothrow" function call. */
2185 if (TREE_NOTHROW (exp))
2186 flags |= ECF_NOTHROW;
2188 /* See if we can find a DECL-node for the actual function.
2189 As a result, decide whether this is a call to an integrable function. */
2191 fndecl = get_callee_fndecl (exp);
2194 fntype = TREE_TYPE (fndecl);
2196 && fndecl != current_function_decl
2197 && DECL_INLINE (fndecl)
2198 && DECL_STRUCT_FUNCTION (fndecl)
2199 && DECL_STRUCT_FUNCTION (fndecl)->inlinable)
2201 else if (! TREE_ADDRESSABLE (fndecl))
2203 /* In case this function later becomes inlinable,
2204 record that there was already a non-inline call to it.
2206 Use abstraction instead of setting TREE_ADDRESSABLE
2208 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2211 warning ("%Jcan't inline call to '%F'", fndecl, fndecl);
2212 warning ("called from here");
2214 (*lang_hooks.mark_addressable) (fndecl);
2218 && lookup_attribute ("warn_unused_result",
2219 TYPE_ATTRIBUTES (TREE_TYPE (fndecl))))
2220 warning ("ignoring return value of `%D', "
2221 "declared with attribute warn_unused_result", fndecl);
2223 flags |= flags_from_decl_or_type (fndecl);
2226 /* If we don't have specific function to call, see if we have a
2227 attributes set in the type. */
2230 fntype = TREE_TYPE (TREE_TYPE (p));
2232 && lookup_attribute ("warn_unused_result", TYPE_ATTRIBUTES (fntype)))
2233 warning ("ignoring return value of function "
2234 "declared with attribute warn_unused_result");
2235 flags |= flags_from_decl_or_type (fntype);
2238 struct_value = targetm.calls.struct_value_rtx (fntype, 0);
2240 /* Warn if this value is an aggregate type,
2241 regardless of which calling convention we are using for it. */
2242 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2243 warning ("function call has aggregate value");
2245 /* If the result of a pure or const function call is ignored (or void),
2246 and none of its arguments are volatile, we can avoid expanding the
2247 call and just evaluate the arguments for side-effects. */
2248 if ((flags & (ECF_CONST | ECF_PURE))
2249 && (ignore || target == const0_rtx
2250 || TYPE_MODE (TREE_TYPE (exp)) == VOIDmode))
2252 bool volatilep = false;
2255 for (arg = actparms; arg; arg = TREE_CHAIN (arg))
2256 if (TREE_THIS_VOLATILE (TREE_VALUE (arg)))
2264 for (arg = actparms; arg; arg = TREE_CHAIN (arg))
2265 expand_expr (TREE_VALUE (arg), const0_rtx,
2266 VOIDmode, EXPAND_NORMAL);
2271 #ifdef REG_PARM_STACK_SPACE
2272 #ifdef MAYBE_REG_PARM_STACK_SPACE
2273 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
2275 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2279 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2280 if (reg_parm_stack_space > 0 && PUSH_ARGS)
2281 must_preallocate = 1;
2284 /* Set up a place to return a structure. */
2286 /* Cater to broken compilers. */
2287 if (aggregate_value_p (exp, fndecl))
2289 /* This call returns a big structure. */
2290 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
2292 #ifdef PCC_STATIC_STRUCT_RETURN
2294 pcc_struct_value = 1;
2295 /* Easier than making that case work right. */
2298 /* In case this is a static function, note that it has been
2300 if (! TREE_ADDRESSABLE (fndecl))
2301 (*lang_hooks.mark_addressable) (fndecl);
2305 #else /* not PCC_STATIC_STRUCT_RETURN */
2307 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2309 if (CALL_EXPR_HAS_RETURN_SLOT_ADDR (exp))
2311 /* The structure value address arg is already in actparms.
2312 Pull it out. It might be nice to just leave it there, but
2313 we need to set structure_value_addr. */
2314 tree return_arg = TREE_VALUE (actparms);
2315 actparms = TREE_CHAIN (actparms);
2316 structure_value_addr = expand_expr (return_arg, NULL_RTX,
2317 VOIDmode, EXPAND_NORMAL);
2319 else if (target && GET_CODE (target) == MEM)
2320 structure_value_addr = XEXP (target, 0);
2323 /* For variable-sized objects, we must be called with a target
2324 specified. If we were to allocate space on the stack here,
2325 we would have no way of knowing when to free it. */
2326 rtx d = assign_temp (TREE_TYPE (exp), 1, 1, 1);
2328 mark_temp_addr_taken (d);
2329 structure_value_addr = XEXP (d, 0);
2333 #endif /* not PCC_STATIC_STRUCT_RETURN */
2336 /* If called function is inline, try to integrate it. */
2340 rtx temp = try_to_integrate (fndecl, actparms, target,
2341 ignore, TREE_TYPE (exp),
2342 structure_value_addr);
2343 if (temp != (rtx) (size_t) - 1)
2347 /* Figure out the amount to which the stack should be aligned. */
2348 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2351 struct cgraph_rtl_info *i = cgraph_rtl_info (fndecl);
2352 if (i && i->preferred_incoming_stack_boundary)
2353 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
2356 /* Operand 0 is a pointer-to-function; get the type of the function. */
2357 funtype = TREE_TYPE (addr);
2358 if (! POINTER_TYPE_P (funtype))
2360 funtype = TREE_TYPE (funtype);
2362 /* Munge the tree to split complex arguments into their imaginary
2364 if (SPLIT_COMPLEX_ARGS)
2366 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
2367 actparms = split_complex_values (actparms);
2370 type_arg_types = TYPE_ARG_TYPES (funtype);
2372 /* See if this is a call to a function that can return more than once
2373 or a call to longjmp or malloc. */
2374 flags |= special_function_p (fndecl, flags);
2376 if (flags & ECF_MAY_BE_ALLOCA)
2377 current_function_calls_alloca = 1;
2379 /* If struct_value_rtx is 0, it means pass the address
2380 as if it were an extra parameter. */
2381 if (structure_value_addr && struct_value == 0)
2383 /* If structure_value_addr is a REG other than
2384 virtual_outgoing_args_rtx, we can use always use it. If it
2385 is not a REG, we must always copy it into a register.
2386 If it is virtual_outgoing_args_rtx, we must copy it to another
2387 register in some cases. */
2388 rtx temp = (GET_CODE (structure_value_addr) != REG
2389 || (ACCUMULATE_OUTGOING_ARGS
2390 && stack_arg_under_construction
2391 && structure_value_addr == virtual_outgoing_args_rtx)
2392 ? copy_addr_to_reg (convert_memory_address
2393 (Pmode, structure_value_addr))
2394 : structure_value_addr);
2397 = tree_cons (error_mark_node,
2398 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2401 structure_value_addr_parm = 1;
2404 /* Count the arguments and set NUM_ACTUALS. */
2405 for (p = actparms, num_actuals = 0; p; p = TREE_CHAIN (p))
2408 /* Compute number of named args.
2409 Normally, don't include the last named arg if anonymous args follow.
2410 We do include the last named arg if
2411 targetm.calls.strict_argument_naming() returns nonzero.
2412 (If no anonymous args follow, the result of list_length is actually
2413 one too large. This is harmless.)
2415 If targetm.calls.pretend_outgoing_varargs_named() returns
2416 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2417 this machine will be able to place unnamed args that were passed
2418 in registers into the stack. So treat all args as named. This
2419 allows the insns emitting for a specific argument list to be
2420 independent of the function declaration.
2422 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2423 we do not have any reliable way to pass unnamed args in
2424 registers, so we must force them into memory. */
2426 if ((targetm.calls.strict_argument_naming (&args_so_far)
2427 || ! targetm.calls.pretend_outgoing_varargs_named (&args_so_far))
2428 && type_arg_types != 0)
2430 = (list_length (type_arg_types)
2431 /* Don't include the last named arg. */
2432 - (targetm.calls.strict_argument_naming (&args_so_far) ? 0 : 1)
2433 /* Count the struct value address, if it is passed as a parm. */
2434 + structure_value_addr_parm);
2436 /* If we know nothing, treat all args as named. */
2437 n_named_args = num_actuals;
2439 /* Start updating where the next arg would go.
2441 On some machines (such as the PA) indirect calls have a different
2442 calling convention than normal calls. The fourth argument in
2443 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2445 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, fndecl, n_named_args);
2447 /* Make a vector to hold all the information about each arg. */
2448 args = alloca (num_actuals * sizeof (struct arg_data));
2449 memset (args, 0, num_actuals * sizeof (struct arg_data));
2451 /* Build up entries in the ARGS array, compute the size of the
2452 arguments into ARGS_SIZE, etc. */
2453 initialize_argument_information (num_actuals, args, &args_size,
2454 n_named_args, actparms, fndecl,
2455 &args_so_far, reg_parm_stack_space,
2456 &old_stack_level, &old_pending_adj,
2457 &must_preallocate, &flags,
2458 CALL_FROM_THUNK_P (exp));
2462 /* If this function requires a variable-sized argument list, don't
2463 try to make a cse'able block for this call. We may be able to
2464 do this eventually, but it is too complicated to keep track of
2465 what insns go in the cse'able block and which don't. */
2467 flags &= ~ECF_LIBCALL_BLOCK;
2468 must_preallocate = 1;
2471 /* Now make final decision about preallocating stack space. */
2472 must_preallocate = finalize_must_preallocate (must_preallocate,
2476 /* If the structure value address will reference the stack pointer, we
2477 must stabilize it. We don't need to do this if we know that we are
2478 not going to adjust the stack pointer in processing this call. */
2480 if (structure_value_addr
2481 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2482 || reg_mentioned_p (virtual_outgoing_args_rtx,
2483 structure_value_addr))
2485 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2486 structure_value_addr = copy_to_reg (structure_value_addr);
2488 /* Tail calls can make things harder to debug, and we're traditionally
2489 pushed these optimizations into -O2. Don't try if we're already
2490 expanding a call, as that means we're an argument. Don't try if
2491 there's cleanups, as we know there's code to follow the call.
2493 If rtx_equal_function_value_matters is false, that means we've
2494 finished with regular parsing. Which means that some of the
2495 machinery we use to generate tail-calls is no longer in place.
2496 This is most often true of sjlj-exceptions, which we couldn't
2497 tail-call to anyway.
2499 If current_nesting_level () == 0, we're being called after
2500 the function body has been expanded. This can happen when
2501 setting up trampolines in expand_function_end. */
2502 if (currently_expanding_call++ != 0
2503 || !flag_optimize_sibling_calls
2504 || !rtx_equal_function_value_matters
2505 || current_nesting_level () == 0
2506 || any_pending_cleanups ()
2508 try_tail_call = try_tail_recursion = 0;
2510 /* Tail recursion fails, when we are not dealing with recursive calls. */
2511 if (!try_tail_recursion
2512 || TREE_CODE (addr) != ADDR_EXPR
2513 || TREE_OPERAND (addr, 0) != current_function_decl)
2514 try_tail_recursion = 0;
2516 /* Rest of purposes for tail call optimizations to fail. */
2518 #ifdef HAVE_sibcall_epilogue
2519 !HAVE_sibcall_epilogue
2524 /* Doing sibling call optimization needs some work, since
2525 structure_value_addr can be allocated on the stack.
2526 It does not seem worth the effort since few optimizable
2527 sibling calls will return a structure. */
2528 || structure_value_addr != NULL_RTX
2529 /* Check whether the target is able to optimize the call
2531 || !(*targetm.function_ok_for_sibcall) (fndecl, exp)
2532 /* Functions that do not return exactly once may not be sibcall
2534 || (flags & (ECF_RETURNS_TWICE | ECF_LONGJMP | ECF_NORETURN))
2535 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr)))
2536 /* If the called function is nested in the current one, it might access
2537 some of the caller's arguments, but could clobber them beforehand if
2538 the argument areas are shared. */
2539 || (fndecl && decl_function_context (fndecl) == current_function_decl)
2540 /* If this function requires more stack slots than the current
2541 function, we cannot change it into a sibling call. */
2542 || args_size.constant > current_function_args_size
2543 /* If the callee pops its own arguments, then it must pop exactly
2544 the same number of arguments as the current function. */
2545 || (RETURN_POPS_ARGS (fndecl, funtype, args_size.constant)
2546 != RETURN_POPS_ARGS (current_function_decl,
2547 TREE_TYPE (current_function_decl),
2548 current_function_args_size))
2549 || !(*lang_hooks.decls.ok_for_sibcall) (fndecl))
2552 if (try_tail_call || try_tail_recursion)
2555 actparms = NULL_TREE;
2556 /* Ok, we're going to give the tail call the old college try.
2557 This means we're going to evaluate the function arguments
2558 up to three times. There are two degrees of badness we can
2559 encounter, those that can be unsaved and those that can't.
2560 (See unsafe_for_reeval commentary for details.)
2562 Generate a new argument list. Pass safe arguments through
2563 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2564 For hard badness, evaluate them now and put their resulting
2565 rtx in a temporary VAR_DECL.
2567 initialize_argument_information has ordered the array for the
2568 order to be pushed, and we must remember this when reconstructing
2569 the original argument order. */
2571 if (PUSH_ARGS_REVERSED)
2580 i = num_actuals - 1;
2584 for (; i != end; i += inc)
2586 args[i].tree_value = fix_unsafe_tree (args[i].tree_value);
2587 /* We need to build actparms for optimize_tail_recursion. We can
2588 safely trash away TREE_PURPOSE, since it is unused by this
2590 if (try_tail_recursion)
2591 actparms = tree_cons (NULL_TREE, args[i].tree_value, actparms);
2593 /* Do the same for the function address if it is an expression. */
2595 addr = fix_unsafe_tree (addr);
2596 /* Expanding one of those dangerous arguments could have added
2597 cleanups, but otherwise give it a whirl. */
2598 if (any_pending_cleanups ())
2599 try_tail_call = try_tail_recursion = 0;
2602 /* Generate a tail recursion sequence when calling ourselves. */
2604 if (try_tail_recursion)
2606 /* We want to emit any pending stack adjustments before the tail
2607 recursion "call". That way we know any adjustment after the tail
2608 recursion call can be ignored if we indeed use the tail recursion
2610 int save_pending_stack_adjust = pending_stack_adjust;
2611 int save_stack_pointer_delta = stack_pointer_delta;
2613 /* Emit any queued insns now; otherwise they would end up in
2614 only one of the alternates. */
2617 /* Use a new sequence to hold any RTL we generate. We do not even
2618 know if we will use this RTL yet. The final decision can not be
2619 made until after RTL generation for the entire function is
2622 /* If expanding any of the arguments creates cleanups, we can't
2623 do a tailcall. So, we'll need to pop the pending cleanups
2624 list. If, however, all goes well, and there are no cleanups
2625 then the call to expand_start_target_temps will have no
2627 expand_start_target_temps ();
2628 if (optimize_tail_recursion (actparms, get_last_insn ()))
2630 if (any_pending_cleanups ())
2631 try_tail_call = try_tail_recursion = 0;
2633 tail_recursion_insns = get_insns ();
2635 expand_end_target_temps ();
2638 /* Restore the original pending stack adjustment for the sibling and
2639 normal call cases below. */
2640 pending_stack_adjust = save_pending_stack_adjust;
2641 stack_pointer_delta = save_stack_pointer_delta;
2644 if (profile_arc_flag && (flags & ECF_FORK_OR_EXEC))
2646 /* A fork duplicates the profile information, and an exec discards
2647 it. We can't rely on fork/exec to be paired. So write out the
2648 profile information we have gathered so far, and clear it. */
2649 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2650 is subject to race conditions, just as with multithreaded
2653 emit_library_call (gcov_flush_libfunc, LCT_ALWAYS_RETURN, VOIDmode, 0);
2656 /* Ensure current function's preferred stack boundary is at least
2657 what we need. We don't have to increase alignment for recursive
2659 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2660 && fndecl != current_function_decl)
2661 cfun->preferred_stack_boundary = preferred_stack_boundary;
2662 if (fndecl == current_function_decl)
2663 cfun->recursive_call_emit = true;
2665 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2667 function_call_count++;
2669 /* We want to make two insn chains; one for a sibling call, the other
2670 for a normal call. We will select one of the two chains after
2671 initial RTL generation is complete. */
2672 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
2674 int sibcall_failure = 0;
2675 /* We want to emit any pending stack adjustments before the tail
2676 recursion "call". That way we know any adjustment after the tail
2677 recursion call can be ignored if we indeed use the tail recursion
2679 int save_pending_stack_adjust = 0;
2680 int save_stack_pointer_delta = 0;
2682 rtx before_call, next_arg_reg;
2686 /* Emit any queued insns now; otherwise they would end up in
2687 only one of the alternates. */
2690 /* State variables we need to save and restore between
2692 save_pending_stack_adjust = pending_stack_adjust;
2693 save_stack_pointer_delta = stack_pointer_delta;
2696 flags &= ~ECF_SIBCALL;
2698 flags |= ECF_SIBCALL;
2700 /* Other state variables that we must reinitialize each time
2701 through the loop (that are not initialized by the loop itself). */
2705 /* Start a new sequence for the normal call case.
2707 From this point on, if the sibling call fails, we want to set
2708 sibcall_failure instead of continuing the loop. */
2713 /* We know at this point that there are not currently any
2714 pending cleanups. If, however, in the process of evaluating
2715 the arguments we were to create some, we'll need to be
2716 able to get rid of them. */
2717 expand_start_target_temps ();
2720 /* Don't let pending stack adjusts add up to too much.
2721 Also, do all pending adjustments now if there is any chance
2722 this might be a call to alloca or if we are expanding a sibling
2723 call sequence or if we are calling a function that is to return
2724 with stack pointer depressed. */
2725 if (pending_stack_adjust >= 32
2726 || (pending_stack_adjust > 0
2727 && (flags & (ECF_MAY_BE_ALLOCA | ECF_SP_DEPRESSED)))
2729 do_pending_stack_adjust ();
2731 /* When calling a const function, we must pop the stack args right away,
2732 so that the pop is deleted or moved with the call. */
2733 if (pass && (flags & ECF_LIBCALL_BLOCK))
2736 #ifdef FINAL_REG_PARM_STACK_SPACE
2737 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2740 /* Precompute any arguments as needed. */
2742 precompute_arguments (flags, num_actuals, args);
2744 /* Now we are about to start emitting insns that can be deleted
2745 if a libcall is deleted. */
2746 if (pass && (flags & (ECF_LIBCALL_BLOCK | ECF_MALLOC)))
2749 adjusted_args_size = args_size;
2750 /* Compute the actual size of the argument block required. The variable
2751 and constant sizes must be combined, the size may have to be rounded,
2752 and there may be a minimum required size. When generating a sibcall
2753 pattern, do not round up, since we'll be re-using whatever space our
2755 unadjusted_args_size
2756 = compute_argument_block_size (reg_parm_stack_space,
2757 &adjusted_args_size,
2759 : preferred_stack_boundary));
2761 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2763 /* The argument block when performing a sibling call is the
2764 incoming argument block. */
2767 argblock = virtual_incoming_args_rtx;
2769 #ifdef STACK_GROWS_DOWNWARD
2770 = plus_constant (argblock, current_function_pretend_args_size);
2772 = plus_constant (argblock, -current_function_pretend_args_size);
2774 stored_args_map = sbitmap_alloc (args_size.constant);
2775 sbitmap_zero (stored_args_map);
2778 /* If we have no actual push instructions, or shouldn't use them,
2779 make space for all args right now. */
2780 else if (adjusted_args_size.var != 0)
2782 if (old_stack_level == 0)
2784 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2785 old_stack_pointer_delta = stack_pointer_delta;
2786 old_pending_adj = pending_stack_adjust;
2787 pending_stack_adjust = 0;
2788 /* stack_arg_under_construction says whether a stack arg is
2789 being constructed at the old stack level. Pushing the stack
2790 gets a clean outgoing argument block. */
2791 old_stack_arg_under_construction = stack_arg_under_construction;
2792 stack_arg_under_construction = 0;
2794 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2798 /* Note that we must go through the motions of allocating an argument
2799 block even if the size is zero because we may be storing args
2800 in the area reserved for register arguments, which may be part of
2803 int needed = adjusted_args_size.constant;
2805 /* Store the maximum argument space used. It will be pushed by
2806 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2809 if (needed > current_function_outgoing_args_size)
2810 current_function_outgoing_args_size = needed;
2812 if (must_preallocate)
2814 if (ACCUMULATE_OUTGOING_ARGS)
2816 /* Since the stack pointer will never be pushed, it is
2817 possible for the evaluation of a parm to clobber
2818 something we have already written to the stack.
2819 Since most function calls on RISC machines do not use
2820 the stack, this is uncommon, but must work correctly.
2822 Therefore, we save any area of the stack that was already
2823 written and that we are using. Here we set up to do this
2824 by making a new stack usage map from the old one. The
2825 actual save will be done by store_one_arg.
2827 Another approach might be to try to reorder the argument
2828 evaluations to avoid this conflicting stack usage. */
2830 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2831 /* Since we will be writing into the entire argument area,
2832 the map must be allocated for its entire size, not just
2833 the part that is the responsibility of the caller. */
2834 needed += reg_parm_stack_space;
2837 #ifdef ARGS_GROW_DOWNWARD
2838 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2841 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2844 stack_usage_map = alloca (highest_outgoing_arg_in_use);
2846 if (initial_highest_arg_in_use)
2847 memcpy (stack_usage_map, initial_stack_usage_map,
2848 initial_highest_arg_in_use);
2850 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2851 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2852 (highest_outgoing_arg_in_use
2853 - initial_highest_arg_in_use));
2856 /* The address of the outgoing argument list must not be
2857 copied to a register here, because argblock would be left
2858 pointing to the wrong place after the call to
2859 allocate_dynamic_stack_space below. */
2861 argblock = virtual_outgoing_args_rtx;
2865 if (inhibit_defer_pop == 0)
2867 /* Try to reuse some or all of the pending_stack_adjust
2868 to get this space. */
2870 = (combine_pending_stack_adjustment_and_call
2871 (unadjusted_args_size,
2872 &adjusted_args_size,
2873 preferred_unit_stack_boundary));
2875 /* combine_pending_stack_adjustment_and_call computes
2876 an adjustment before the arguments are allocated.
2877 Account for them and see whether or not the stack
2878 needs to go up or down. */
2879 needed = unadjusted_args_size - needed;
2883 /* We're releasing stack space. */
2884 /* ??? We can avoid any adjustment at all if we're
2885 already aligned. FIXME. */
2886 pending_stack_adjust = -needed;
2887 do_pending_stack_adjust ();
2891 /* We need to allocate space. We'll do that in
2892 push_block below. */
2893 pending_stack_adjust = 0;
2896 /* Special case this because overhead of `push_block' in
2897 this case is non-trivial. */
2899 argblock = virtual_outgoing_args_rtx;
2902 argblock = push_block (GEN_INT (needed), 0, 0);
2903 #ifdef ARGS_GROW_DOWNWARD
2904 argblock = plus_constant (argblock, needed);
2908 /* We only really need to call `copy_to_reg' in the case
2909 where push insns are going to be used to pass ARGBLOCK
2910 to a function call in ARGS. In that case, the stack
2911 pointer changes value from the allocation point to the
2912 call point, and hence the value of
2913 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2914 as well always do it. */
2915 argblock = copy_to_reg (argblock);
2920 if (ACCUMULATE_OUTGOING_ARGS)
2922 /* The save/restore code in store_one_arg handles all
2923 cases except one: a constructor call (including a C
2924 function returning a BLKmode struct) to initialize
2926 if (stack_arg_under_construction)
2928 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2929 rtx push_size = GEN_INT (reg_parm_stack_space
2930 + adjusted_args_size.constant);
2932 rtx push_size = GEN_INT (adjusted_args_size.constant);
2934 if (old_stack_level == 0)
2936 emit_stack_save (SAVE_BLOCK, &old_stack_level,
2938 old_stack_pointer_delta = stack_pointer_delta;
2939 old_pending_adj = pending_stack_adjust;
2940 pending_stack_adjust = 0;
2941 /* stack_arg_under_construction says whether a stack
2942 arg is being constructed at the old stack level.
2943 Pushing the stack gets a clean outgoing argument
2945 old_stack_arg_under_construction
2946 = stack_arg_under_construction;
2947 stack_arg_under_construction = 0;
2948 /* Make a new map for the new argument list. */
2949 stack_usage_map = alloca (highest_outgoing_arg_in_use);
2950 memset (stack_usage_map, 0, highest_outgoing_arg_in_use);
2951 highest_outgoing_arg_in_use = 0;
2953 allocate_dynamic_stack_space (push_size, NULL_RTX,
2957 /* If argument evaluation might modify the stack pointer,
2958 copy the address of the argument list to a register. */
2959 for (i = 0; i < num_actuals; i++)
2960 if (args[i].pass_on_stack)
2962 argblock = copy_addr_to_reg (argblock);
2967 compute_argument_addresses (args, argblock, num_actuals);
2969 /* If we push args individually in reverse order, perform stack alignment
2970 before the first push (the last arg). */
2971 if (PUSH_ARGS_REVERSED && argblock == 0
2972 && adjusted_args_size.constant != unadjusted_args_size)
2974 /* When the stack adjustment is pending, we get better code
2975 by combining the adjustments. */
2976 if (pending_stack_adjust
2977 && ! (flags & ECF_LIBCALL_BLOCK)
2978 && ! inhibit_defer_pop)
2980 pending_stack_adjust
2981 = (combine_pending_stack_adjustment_and_call
2982 (unadjusted_args_size,
2983 &adjusted_args_size,
2984 preferred_unit_stack_boundary));
2985 do_pending_stack_adjust ();
2987 else if (argblock == 0)
2988 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2989 - unadjusted_args_size));
2991 /* Now that the stack is properly aligned, pops can't safely
2992 be deferred during the evaluation of the arguments. */
2995 funexp = rtx_for_function_call (fndecl, addr);
2997 /* Figure out the register where the value, if any, will come back. */
2999 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
3000 && ! structure_value_addr)
3002 if (pcc_struct_value)
3003 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
3004 fndecl, (pass == 0));
3006 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
3009 /* Precompute all register parameters. It isn't safe to compute anything
3010 once we have started filling any specific hard regs. */
3011 precompute_register_parameters (num_actuals, args, ®_parm_seen);
3013 #ifdef REG_PARM_STACK_SPACE
3014 /* Save the fixed argument area if it's part of the caller's frame and
3015 is clobbered by argument setup for this call. */
3016 if (ACCUMULATE_OUTGOING_ARGS && pass)
3017 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3018 &low_to_save, &high_to_save);
3021 /* Now store (and compute if necessary) all non-register parms.
3022 These come before register parms, since they can require block-moves,
3023 which could clobber the registers used for register parms.
3024 Parms which have partial registers are not stored here,
3025 but we do preallocate space here if they want that. */
3027 for (i = 0; i < num_actuals; i++)
3028 if (args[i].reg == 0 || args[i].pass_on_stack)
3030 rtx before_arg = get_last_insn ();
3032 if (store_one_arg (&args[i], argblock, flags,
3033 adjusted_args_size.var != 0,
3034 reg_parm_stack_space)
3036 && check_sibcall_argument_overlap (before_arg,
3038 sibcall_failure = 1;
3040 if (flags & ECF_CONST
3042 && args[i].value == args[i].stack)
3043 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3044 gen_rtx_USE (VOIDmode,
3049 /* If we have a parm that is passed in registers but not in memory
3050 and whose alignment does not permit a direct copy into registers,
3051 make a group of pseudos that correspond to each register that we
3053 if (STRICT_ALIGNMENT)
3054 store_unaligned_arguments_into_pseudos (args, num_actuals);
3056 /* Now store any partially-in-registers parm.
3057 This is the last place a block-move can happen. */
3059 for (i = 0; i < num_actuals; i++)
3060 if (args[i].partial != 0 && ! args[i].pass_on_stack)
3062 rtx before_arg = get_last_insn ();
3064 if (store_one_arg (&args[i], argblock, flags,
3065 adjusted_args_size.var != 0,
3066 reg_parm_stack_space)
3068 && check_sibcall_argument_overlap (before_arg,
3070 sibcall_failure = 1;
3073 /* If we pushed args in forward order, perform stack alignment
3074 after pushing the last arg. */
3075 if (!PUSH_ARGS_REVERSED && argblock == 0)
3076 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3077 - unadjusted_args_size));
3079 /* If register arguments require space on the stack and stack space
3080 was not preallocated, allocate stack space here for arguments
3081 passed in registers. */
3082 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3083 if (!ACCUMULATE_OUTGOING_ARGS
3084 && must_preallocate == 0 && reg_parm_stack_space > 0)
3085 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3088 /* Pass the function the address in which to return a
3090 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3092 structure_value_addr
3093 = convert_memory_address (Pmode, structure_value_addr);
3094 emit_move_insn (struct_value,
3096 force_operand (structure_value_addr,
3099 if (GET_CODE (struct_value) == REG)
3100 use_reg (&call_fusage, struct_value);
3103 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
3104 reg_parm_seen, pass == 0);
3106 load_register_parameters (args, num_actuals, &call_fusage, flags,
3107 pass == 0, &sibcall_failure);
3109 /* Perform postincrements before actually calling the function. */
3112 /* Save a pointer to the last insn before the call, so that we can
3113 later safely search backwards to find the CALL_INSN. */
3114 before_call = get_last_insn ();
3116 /* Set up next argument register. For sibling calls on machines
3117 with register windows this should be the incoming register. */
3118 #ifdef FUNCTION_INCOMING_ARG
3120 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
3124 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
3127 /* All arguments and registers used for the call must be set up by
3130 /* Stack must be properly aligned now. */
3131 if (pass && stack_pointer_delta % preferred_unit_stack_boundary)
3134 /* Generate the actual call instruction. */
3135 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
3136 adjusted_args_size.constant, struct_value_size,
3137 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3138 flags, & args_so_far);
3140 /* If call is cse'able, make appropriate pair of reg-notes around it.
3141 Test valreg so we don't crash; may safely ignore `const'
3142 if return type is void. Disable for PARALLEL return values, because
3143 we have no way to move such values into a pseudo register. */
3144 if (pass && (flags & ECF_LIBCALL_BLOCK))
3148 bool failed = valreg == 0 || GET_CODE (valreg) == PARALLEL;
3150 insns = get_insns ();
3152 /* Expansion of block moves possibly introduced a loop that may
3153 not appear inside libcall block. */
3154 for (insn = insns; insn; insn = NEXT_INSN (insn))
3155 if (GET_CODE (insn) == JUMP_INSN)
3166 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3168 /* Mark the return value as a pointer if needed. */
3169 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3170 mark_reg_pointer (temp,
3171 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
3174 if (flag_unsafe_math_optimizations
3176 && DECL_BUILT_IN (fndecl)
3177 && (DECL_FUNCTION_CODE (fndecl) == BUILT_IN_SQRT
3178 || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_SQRTF
3179 || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_SQRTL))
3180 note = gen_rtx_fmt_e (SQRT,
3182 args[0].initial_value);
3185 /* Construct an "equal form" for the value which
3186 mentions all the arguments in order as well as
3187 the function name. */
3188 for (i = 0; i < num_actuals; i++)
3189 note = gen_rtx_EXPR_LIST (VOIDmode,
3190 args[i].initial_value, note);
3191 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
3193 if (flags & ECF_PURE)
3194 note = gen_rtx_EXPR_LIST (VOIDmode,
3195 gen_rtx_USE (VOIDmode,
3196 gen_rtx_MEM (BLKmode,
3197 gen_rtx_SCRATCH (VOIDmode))),
3200 emit_libcall_block (insns, temp, valreg, note);
3205 else if (pass && (flags & ECF_MALLOC))
3207 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3210 /* The return value from a malloc-like function is a pointer. */
3211 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3212 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3214 emit_move_insn (temp, valreg);
3216 /* The return value from a malloc-like function can not alias
3218 last = get_last_insn ();
3220 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
3222 /* Write out the sequence. */
3223 insns = get_insns ();
3229 /* For calls to `setjmp', etc., inform flow.c it should complain
3230 if nonvolatile values are live. For functions that cannot return,
3231 inform flow that control does not fall through. */
3233 if ((flags & (ECF_NORETURN | ECF_LONGJMP)) || pass == 0)
3235 /* The barrier must be emitted
3236 immediately after the CALL_INSN. Some ports emit more
3237 than just a CALL_INSN above, so we must search for it here. */
3239 rtx last = get_last_insn ();
3240 while (GET_CODE (last) != CALL_INSN)
3242 last = PREV_INSN (last);
3243 /* There was no CALL_INSN? */
3244 if (last == before_call)
3248 emit_barrier_after (last);
3250 /* Stack adjustments after a noreturn call are dead code.
3251 However when NO_DEFER_POP is in effect, we must preserve
3252 stack_pointer_delta. */
3253 if (inhibit_defer_pop == 0)
3255 stack_pointer_delta = old_stack_allocated;
3256 pending_stack_adjust = 0;
3260 if (flags & ECF_LONGJMP)
3261 current_function_calls_longjmp = 1;
3263 /* If value type not void, return an rtx for the value. */
3265 /* If there are cleanups to be called, don't use a hard reg as target.
3266 We need to double check this and see if it matters anymore. */
3267 if (any_pending_cleanups ())
3269 if (target && REG_P (target)
3270 && REGNO (target) < FIRST_PSEUDO_REGISTER)
3272 sibcall_failure = 1;
3275 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
3277 target = const0_rtx;
3278 else if (structure_value_addr)
3280 if (target == 0 || GET_CODE (target) != MEM)
3283 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3284 memory_address (TYPE_MODE (TREE_TYPE (exp)),
3285 structure_value_addr));
3286 set_mem_attributes (target, exp, 1);
3289 else if (pcc_struct_value)
3291 /* This is the special C++ case where we need to
3292 know what the true target was. We take care to
3293 never use this value more than once in one expression. */
3294 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3295 copy_to_reg (valreg));
3296 set_mem_attributes (target, exp, 1);
3298 /* Handle calls that return values in multiple non-contiguous locations.
3299 The Irix 6 ABI has examples of this. */
3300 else if (GET_CODE (valreg) == PARALLEL)
3302 /* Second condition is added because "target" is freed at the
3303 the end of "pass0" for -O2 when call is made to
3304 expand_end_target_temps (). Its "in_use" flag has been set
3305 to false, so allocate a new temp. */
3306 if (target == 0 || (pass == 1 && target == temp_target))
3308 /* This will only be assigned once, so it can be readonly. */
3309 tree nt = build_qualified_type (TREE_TYPE (exp),
3310 (TYPE_QUALS (TREE_TYPE (exp))
3311 | TYPE_QUAL_CONST));
3313 target = assign_temp (nt, 0, 1, 1);
3314 temp_target = target;
3315 preserve_temp_slots (target);
3318 if (! rtx_equal_p (target, valreg))
3319 emit_group_store (target, valreg, TREE_TYPE (exp),
3320 int_size_in_bytes (TREE_TYPE (exp)));
3322 /* We can not support sibling calls for this case. */
3323 sibcall_failure = 1;
3326 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
3327 && GET_MODE (target) == GET_MODE (valreg))
3329 /* TARGET and VALREG cannot be equal at this point because the
3330 latter would not have REG_FUNCTION_VALUE_P true, while the
3331 former would if it were referring to the same register.
3333 If they refer to the same register, this move will be a no-op,
3334 except when function inlining is being done. */
3335 emit_move_insn (target, valreg);
3337 /* If we are setting a MEM, this code must be executed. Since it is
3338 emitted after the call insn, sibcall optimization cannot be
3339 performed in that case. */
3340 if (GET_CODE (target) == MEM)
3341 sibcall_failure = 1;
3343 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3345 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3347 /* We can not support sibling calls for this case. */
3348 sibcall_failure = 1;
3352 if (shift_returned_value (TREE_TYPE (exp), &valreg))
3353 sibcall_failure = 1;
3355 target = copy_to_reg (valreg);
3358 if (targetm.calls.promote_function_return(funtype))
3360 /* If we promoted this return value, make the proper SUBREG. TARGET
3361 might be const0_rtx here, so be careful. */
3362 if (GET_CODE (target) == REG
3363 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3364 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3366 tree type = TREE_TYPE (exp);
3367 int unsignedp = TREE_UNSIGNED (type);
3370 /* If we don't promote as expected, something is wrong. */
3371 if (GET_MODE (target)
3372 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
3375 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3376 && GET_MODE_SIZE (GET_MODE (target))
3377 > GET_MODE_SIZE (TYPE_MODE (type)))
3379 offset = GET_MODE_SIZE (GET_MODE (target))
3380 - GET_MODE_SIZE (TYPE_MODE (type));
3381 if (! BYTES_BIG_ENDIAN)
3382 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3383 else if (! WORDS_BIG_ENDIAN)
3384 offset %= UNITS_PER_WORD;
3386 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3387 SUBREG_PROMOTED_VAR_P (target) = 1;
3388 SUBREG_PROMOTED_UNSIGNED_SET (target, unsignedp);
3392 /* If size of args is variable or this was a constructor call for a stack
3393 argument, restore saved stack-pointer value. */
3395 if (old_stack_level && ! (flags & ECF_SP_DEPRESSED))
3397 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3398 stack_pointer_delta = old_stack_pointer_delta;
3399 pending_stack_adjust = old_pending_adj;
3400 stack_arg_under_construction = old_stack_arg_under_construction;
3401 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3402 stack_usage_map = initial_stack_usage_map;
3403 sibcall_failure = 1;
3405 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3407 #ifdef REG_PARM_STACK_SPACE
3409 restore_fixed_argument_area (save_area, argblock,
3410 high_to_save, low_to_save);
3413 /* If we saved any argument areas, restore them. */
3414 for (i = 0; i < num_actuals; i++)
3415 if (args[i].save_area)
3417 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3419 = gen_rtx_MEM (save_mode,
3420 memory_address (save_mode,
3421 XEXP (args[i].stack_slot, 0)));
3423 if (save_mode != BLKmode)
3424 emit_move_insn (stack_area, args[i].save_area);
3426 emit_block_move (stack_area, args[i].save_area,
3427 GEN_INT (args[i].locate.size.constant),
3428 BLOCK_OP_CALL_PARM);
3431 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3432 stack_usage_map = initial_stack_usage_map;
3435 /* If this was alloca, record the new stack level for nonlocal gotos.
3436 Check for the handler slots since we might not have a save area
3437 for non-local gotos. */
3439 if ((flags & ECF_MAY_BE_ALLOCA) && nonlocal_goto_handler_slots != 0)
3440 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3442 /* Free up storage we no longer need. */
3443 for (i = 0; i < num_actuals; ++i)
3444 if (args[i].aligned_regs)
3445 free (args[i].aligned_regs);
3449 /* Undo the fake expand_start_target_temps we did earlier. If
3450 there had been any cleanups created, we've already set
3452 expand_end_target_temps ();
3455 /* If this function is returning into a memory location marked as
3456 readonly, it means it is initializing that location. We normally treat
3457 functions as not clobbering such locations, so we need to specify that
3458 this one does. We do this by adding the appropriate CLOBBER to the
3459 CALL_INSN function usage list. This cannot be done by emitting a
3460 standalone CLOBBER after the call because the latter would be ignored
3461 by at least the delay slot scheduling pass. We do this now instead of
3462 adding to call_fusage before the call to emit_call_1 because TARGET
3463 may be modified in the meantime. */
3464 if (structure_value_addr != 0 && target != 0
3465 && GET_CODE (target) == MEM && RTX_UNCHANGING_P (target))
3466 add_function_usage_to
3468 gen_rtx_EXPR_LIST (VOIDmode, gen_rtx_CLOBBER (VOIDmode, target),
3471 insns = get_insns ();
3476 tail_call_insns = insns;
3478 /* Restore the pending stack adjustment now that we have
3479 finished generating the sibling call sequence. */
3481 pending_stack_adjust = save_pending_stack_adjust;
3482 stack_pointer_delta = save_stack_pointer_delta;
3484 /* Prepare arg structure for next iteration. */
3485 for (i = 0; i < num_actuals; i++)
3488 args[i].aligned_regs = 0;
3492 sbitmap_free (stored_args_map);
3496 normal_call_insns = insns;
3498 /* Verify that we've deallocated all the stack we used. */
3499 if (! (flags & (ECF_NORETURN | ECF_LONGJMP))
3500 && old_stack_allocated != stack_pointer_delta
3501 - pending_stack_adjust)
3505 /* If something prevents making this a sibling call,
3506 zero out the sequence. */
3507 if (sibcall_failure)
3508 tail_call_insns = NULL_RTX;
3511 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3512 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3513 can happen if the arguments to this function call an inline
3514 function who's expansion contains another CALL_PLACEHOLDER.
3516 If there are any C_Ps in any of these sequences, replace them
3517 with their normal call. */
3519 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3520 if (GET_CODE (insn) == CALL_INSN
3521 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3522 replace_call_placeholder (insn, sibcall_use_normal);
3524 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
3525 if (GET_CODE (insn) == CALL_INSN
3526 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3527 replace_call_placeholder (insn, sibcall_use_normal);
3529 for (insn = tail_recursion_insns; insn; insn = NEXT_INSN (insn))
3530 if (GET_CODE (insn) == CALL_INSN
3531 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3532 replace_call_placeholder (insn, sibcall_use_normal);
3534 /* If this was a potential tail recursion site, then emit a
3535 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3536 One of them will be selected later. */
3537 if (tail_recursion_insns || tail_call_insns)
3539 /* The tail recursion label must be kept around. We could expose
3540 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3541 and makes determining true tail recursion sites difficult.
3543 So we set LABEL_PRESERVE_P here, then clear it when we select
3544 one of the call sequences after rtl generation is complete. */
3545 if (tail_recursion_insns)
3546 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3547 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3549 tail_recursion_insns,
3550 tail_recursion_label));
3553 emit_insn (normal_call_insns);
3555 currently_expanding_call--;
3557 /* If this function returns with the stack pointer depressed, ensure
3558 this block saves and restores the stack pointer, show it was
3559 changed, and adjust for any outgoing arg space. */
3560 if (flags & ECF_SP_DEPRESSED)
3562 clear_pending_stack_adjust ();
3563 emit_insn (gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx));
3564 emit_move_insn (virtual_stack_dynamic_rtx, stack_pointer_rtx);
3565 save_stack_pointer ();
3571 /* Traverse an argument list in VALUES and expand all complex
3572 arguments into their components. */
3574 split_complex_values (tree values)
3578 values = copy_list (values);
3580 for (p = values; p; p = TREE_CHAIN (p))
3582 tree complex_value = TREE_VALUE (p);
3585 complex_type = TREE_TYPE (complex_value);
3589 if (TREE_CODE (complex_type) == COMPLEX_TYPE)
3592 tree real, imag, next;
3594 subtype = TREE_TYPE (complex_type);
3595 complex_value = save_expr (complex_value);
3596 real = build1 (REALPART_EXPR, subtype, complex_value);
3597 imag = build1 (IMAGPART_EXPR, subtype, complex_value);
3599 TREE_VALUE (p) = real;
3600 next = TREE_CHAIN (p);
3601 imag = build_tree_list (NULL_TREE, imag);
3602 TREE_CHAIN (p) = imag;
3603 TREE_CHAIN (imag) = next;
3605 /* Skip the newly created node. */
3613 /* Traverse a list of TYPES and expand all complex types into their
3616 split_complex_types (tree types)
3620 types = copy_list (types);
3622 for (p = types; p; p = TREE_CHAIN (p))
3624 tree complex_type = TREE_VALUE (p);
3626 if (TREE_CODE (complex_type) == COMPLEX_TYPE)
3630 /* Rewrite complex type with component type. */
3631 TREE_VALUE (p) = TREE_TYPE (complex_type);
3632 next = TREE_CHAIN (p);
3634 /* Add another component type for the imaginary part. */
3635 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
3636 TREE_CHAIN (p) = imag;
3637 TREE_CHAIN (imag) = next;
3639 /* Skip the newly created node. */
3647 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3648 The RETVAL parameter specifies whether return value needs to be saved, other
3649 parameters are documented in the emit_library_call function below. */
3652 emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
3653 enum libcall_type fn_type,
3654 enum machine_mode outmode, int nargs, va_list p)
3656 /* Total size in bytes of all the stack-parms scanned so far. */
3657 struct args_size args_size;
3658 /* Size of arguments before any adjustments (such as rounding). */
3659 struct args_size original_args_size;
3665 CUMULATIVE_ARGS args_so_far;
3669 enum machine_mode mode;
3672 struct locate_and_pad_arg_data locate;
3676 int old_inhibit_defer_pop = inhibit_defer_pop;
3677 rtx call_fusage = 0;
3680 int pcc_struct_value = 0;
3681 int struct_value_size = 0;
3683 int reg_parm_stack_space = 0;
3686 tree tfom; /* type_for_mode (outmode, 0) */
3688 #ifdef REG_PARM_STACK_SPACE
3689 /* Define the boundary of the register parm stack space that needs to be
3691 int low_to_save, high_to_save;
3692 rtx save_area = 0; /* Place that it is saved. */
3695 /* Size of the stack reserved for parameter registers. */
3696 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3697 char *initial_stack_usage_map = stack_usage_map;
3699 rtx struct_value = targetm.calls.struct_value_rtx (0, 0);
3701 #ifdef REG_PARM_STACK_SPACE
3702 #ifdef MAYBE_REG_PARM_STACK_SPACE
3703 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3705 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3709 /* By default, library functions can not throw. */
3710 flags = ECF_NOTHROW;
3722 case LCT_CONST_MAKE_BLOCK:
3723 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
3725 case LCT_PURE_MAKE_BLOCK:
3726 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
3729 flags |= ECF_NORETURN;
3732 flags = ECF_NORETURN;
3734 case LCT_ALWAYS_RETURN:
3735 flags = ECF_ALWAYS_RETURN;
3737 case LCT_RETURNS_TWICE:
3738 flags = ECF_RETURNS_TWICE;
3743 /* Ensure current function's preferred stack boundary is at least
3745 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3746 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3748 /* If this kind of value comes back in memory,
3749 decide where in memory it should come back. */
3750 if (outmode != VOIDmode)
3752 tfom = (*lang_hooks.types.type_for_mode) (outmode, 0);
3753 if (aggregate_value_p (tfom, 0))
3755 #ifdef PCC_STATIC_STRUCT_RETURN
3757 = hard_function_value (build_pointer_type (tfom), 0, 0);
3758 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3759 pcc_struct_value = 1;
3761 value = gen_reg_rtx (outmode);
3762 #else /* not PCC_STATIC_STRUCT_RETURN */
3763 struct_value_size = GET_MODE_SIZE (outmode);
3764 if (value != 0 && GET_CODE (value) == MEM)
3767 mem_value = assign_temp (tfom, 0, 1, 1);
3769 /* This call returns a big structure. */
3770 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3774 tfom = void_type_node;
3776 /* ??? Unfinished: must pass the memory address as an argument. */
3778 /* Copy all the libcall-arguments out of the varargs data
3779 and into a vector ARGVEC.
3781 Compute how to pass each argument. We only support a very small subset
3782 of the full argument passing conventions to limit complexity here since
3783 library functions shouldn't have many args. */
3785 argvec = alloca ((nargs + 1) * sizeof (struct arg));
3786 memset (argvec, 0, (nargs + 1) * sizeof (struct arg));
3788 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3789 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far, outmode, fun);
3791 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0, nargs);
3794 args_size.constant = 0;
3799 /* Now we are about to start emitting insns that can be deleted
3800 if a libcall is deleted. */
3801 if (flags & ECF_LIBCALL_BLOCK)
3806 /* If there's a structure value address to be passed,
3807 either pass it in the special place, or pass it as an extra argument. */
3808 if (mem_value && struct_value == 0 && ! pcc_struct_value)
3810 rtx addr = XEXP (mem_value, 0);
3813 /* Make sure it is a reasonable operand for a move or push insn. */
3814 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3815 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3816 addr = force_operand (addr, NULL_RTX);
3818 argvec[count].value = addr;
3819 argvec[count].mode = Pmode;
3820 argvec[count].partial = 0;
3822 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3823 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3824 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3828 locate_and_pad_parm (Pmode, NULL_TREE,
3829 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3832 argvec[count].reg != 0,
3834 0, NULL_TREE, &args_size, &argvec[count].locate);
3836 if (argvec[count].reg == 0 || argvec[count].partial != 0
3837 || reg_parm_stack_space > 0)
3838 args_size.constant += argvec[count].locate.size.constant;
3840 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3845 for (; count < nargs; count++)
3847 rtx val = va_arg (p, rtx);
3848 enum machine_mode mode = va_arg (p, enum machine_mode);
3850 /* We cannot convert the arg value to the mode the library wants here;
3851 must do it earlier where we know the signedness of the arg. */
3853 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3856 /* There's no need to call protect_from_queue, because
3857 either emit_move_insn or emit_push_insn will do that. */
3859 /* Make sure it is a reasonable operand for a move or push insn. */
3860 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3861 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3862 val = force_operand (val, NULL_RTX);
3864 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3865 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3869 #ifdef FUNCTION_ARG_CALLEE_COPIES
3870 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far, mode,
3875 /* loop.c won't look at CALL_INSN_FUNCTION_USAGE of const/pure
3876 functions, so we have to pretend this isn't such a function. */
3877 if (flags & ECF_LIBCALL_BLOCK)
3879 rtx insns = get_insns ();
3883 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3885 /* If this was a CONST function, it is now PURE since
3886 it now reads memory. */
3887 if (flags & ECF_CONST)
3889 flags &= ~ECF_CONST;
3893 if (GET_MODE (val) == MEM && ! must_copy)
3897 slot = assign_temp ((*lang_hooks.types.type_for_mode) (mode, 0),
3899 emit_move_insn (slot, val);
3903 tree type = (*lang_hooks.types.type_for_mode) (mode, 0);
3906 = gen_rtx_MEM (mode,
3907 expand_expr (build1 (ADDR_EXPR,
3908 build_pointer_type (type),
3909 make_tree (type, val)),
3910 NULL_RTX, VOIDmode, 0));
3913 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3914 gen_rtx_USE (VOIDmode, slot),
3917 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3918 gen_rtx_CLOBBER (VOIDmode,
3923 val = force_operand (XEXP (slot, 0), NULL_RTX);
3927 argvec[count].value = val;
3928 argvec[count].mode = mode;
3930 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3932 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3933 argvec[count].partial
3934 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3936 argvec[count].partial = 0;
3939 locate_and_pad_parm (mode, NULL_TREE,
3940 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3943 argvec[count].reg != 0,
3945 argvec[count].partial,
3946 NULL_TREE, &args_size, &argvec[count].locate);
3948 if (argvec[count].locate.size.var)
3951 if (argvec[count].reg == 0 || argvec[count].partial != 0
3952 || reg_parm_stack_space > 0)
3953 args_size.constant += argvec[count].locate.size.constant;
3955 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3958 #ifdef FINAL_REG_PARM_STACK_SPACE
3959 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3962 /* If this machine requires an external definition for library
3963 functions, write one out. */
3964 assemble_external_libcall (fun);
3966 original_args_size = args_size;
3967 args_size.constant = (((args_size.constant
3968 + stack_pointer_delta
3972 - stack_pointer_delta);
3974 args_size.constant = MAX (args_size.constant,
3975 reg_parm_stack_space);
3977 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3978 args_size.constant -= reg_parm_stack_space;
3981 if (args_size.constant > current_function_outgoing_args_size)
3982 current_function_outgoing_args_size = args_size.constant;
3984 if (ACCUMULATE_OUTGOING_ARGS)
3986 /* Since the stack pointer will never be pushed, it is possible for
3987 the evaluation of a parm to clobber something we have already
3988 written to the stack. Since most function calls on RISC machines
3989 do not use the stack, this is uncommon, but must work correctly.
3991 Therefore, we save any area of the stack that was already written
3992 and that we are using. Here we set up to do this by making a new
3993 stack usage map from the old one.
3995 Another approach might be to try to reorder the argument
3996 evaluations to avoid this conflicting stack usage. */
3998 needed = args_size.constant;
4000 #ifndef OUTGOING_REG_PARM_STACK_SPACE
4001 /* Since we will be writing into the entire argument area, the
4002 map must be allocated for its entire size, not just the part that
4003 is the responsibility of the caller. */
4004 needed += reg_parm_stack_space;
4007 #ifdef ARGS_GROW_DOWNWARD
4008 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
4011 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
4014 stack_usage_map = alloca (highest_outgoing_arg_in_use);
4016 if (initial_highest_arg_in_use)
4017 memcpy (stack_usage_map, initial_stack_usage_map,
4018 initial_highest_arg_in_use);
4020 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
4021 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
4022 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
4025 /* We must be careful to use virtual regs before they're instantiated,
4026 and real regs afterwards. Loop optimization, for example, can create
4027 new libcalls after we've instantiated the virtual regs, and if we
4028 use virtuals anyway, they won't match the rtl patterns. */
4030 if (virtuals_instantiated)
4031 argblock = plus_constant (stack_pointer_rtx, STACK_POINTER_OFFSET);
4033 argblock = virtual_outgoing_args_rtx;
4038 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
4041 /* If we push args individually in reverse order, perform stack alignment
4042 before the first push (the last arg). */
4043 if (argblock == 0 && PUSH_ARGS_REVERSED)
4044 anti_adjust_stack (GEN_INT (args_size.constant
4045 - original_args_size.constant));
4047 if (PUSH_ARGS_REVERSED)
4058 #ifdef REG_PARM_STACK_SPACE
4059 if (ACCUMULATE_OUTGOING_ARGS)
4061 /* The argument list is the property of the called routine and it
4062 may clobber it. If the fixed area has been used for previous
4063 parameters, we must save and restore it. */
4064 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
4065 &low_to_save, &high_to_save);
4069 /* Push the args that need to be pushed. */
4071 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4072 are to be pushed. */
4073 for (count = 0; count < nargs; count++, argnum += inc)
4075 enum machine_mode mode = argvec[argnum].mode;
4076 rtx val = argvec[argnum].value;
4077 rtx reg = argvec[argnum].reg;
4078 int partial = argvec[argnum].partial;
4079 int lower_bound = 0, upper_bound = 0, i;
4081 if (! (reg != 0 && partial == 0))
4083 if (ACCUMULATE_OUTGOING_ARGS)
4085 /* If this is being stored into a pre-allocated, fixed-size,
4086 stack area, save any previous data at that location. */
4088 #ifdef ARGS_GROW_DOWNWARD
4089 /* stack_slot is negative, but we want to index stack_usage_map
4090 with positive values. */
4091 upper_bound = -argvec[argnum].locate.offset.constant + 1;
4092 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
4094 lower_bound = argvec[argnum].locate.offset.constant;
4095 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
4099 /* Don't worry about things in the fixed argument area;
4100 it has already been saved. */
4101 if (i < reg_parm_stack_space)
4102 i = reg_parm_stack_space;
4103 while (i < upper_bound && stack_usage_map[i] == 0)
4106 if (i < upper_bound)
4108 /* We need to make a save area. */
4110 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
4111 enum machine_mode save_mode
4112 = mode_for_size (size, MODE_INT, 1);
4114 = plus_constant (argblock,
4115 argvec[argnum].locate.offset.constant);
4117 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
4119 if (save_mode == BLKmode)
4121 argvec[argnum].save_area
4122 = assign_stack_temp (BLKmode,
4123 argvec[argnum].locate.size.constant,
4126 emit_block_move (validize_mem (argvec[argnum].save_area),
4128 GEN_INT (argvec[argnum].locate.size.constant),
4129 BLOCK_OP_CALL_PARM);
4133 argvec[argnum].save_area = gen_reg_rtx (save_mode);
4135 emit_move_insn (argvec[argnum].save_area, stack_area);
4140 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, PARM_BOUNDARY,
4141 partial, reg, 0, argblock,
4142 GEN_INT (argvec[argnum].locate.offset.constant),
4143 reg_parm_stack_space,
4144 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad));
4146 /* Now mark the segment we just used. */
4147 if (ACCUMULATE_OUTGOING_ARGS)
4148 for (i = lower_bound; i < upper_bound; i++)
4149 stack_usage_map[i] = 1;
4155 /* If we pushed args in forward order, perform stack alignment
4156 after pushing the last arg. */
4157 if (argblock == 0 && !PUSH_ARGS_REVERSED)
4158 anti_adjust_stack (GEN_INT (args_size.constant
4159 - original_args_size.constant));
4161 if (PUSH_ARGS_REVERSED)
4166 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0, 0);
4168 /* Now load any reg parms into their regs. */
4170 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4171 are to be pushed. */
4172 for (count = 0; count < nargs; count++, argnum += inc)
4174 rtx val = argvec[argnum].value;
4175 rtx reg = argvec[argnum].reg;
4176 int partial = argvec[argnum].partial;
4178 /* Handle calls that pass values in multiple non-contiguous
4179 locations. The PA64 has examples of this for library calls. */
4180 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4181 emit_group_load (reg, val, NULL_TREE, GET_MODE_SIZE (GET_MODE (val)));
4182 else if (reg != 0 && partial == 0)
4183 emit_move_insn (reg, val);
4188 /* Any regs containing parms remain in use through the call. */
4189 for (count = 0; count < nargs; count++)
4191 rtx reg = argvec[count].reg;
4192 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4193 use_group_regs (&call_fusage, reg);
4195 use_reg (&call_fusage, reg);
4198 /* Pass the function the address in which to return a structure value. */
4199 if (mem_value != 0 && struct_value != 0 && ! pcc_struct_value)
4201 emit_move_insn (struct_value,
4203 force_operand (XEXP (mem_value, 0),
4205 if (GET_CODE (struct_value) == REG)
4206 use_reg (&call_fusage, struct_value);
4209 /* Don't allow popping to be deferred, since then
4210 cse'ing of library calls could delete a call and leave the pop. */
4212 valreg = (mem_value == 0 && outmode != VOIDmode
4213 ? hard_libcall_value (outmode) : NULL_RTX);
4215 /* Stack must be properly aligned now. */
4216 if (stack_pointer_delta & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1))
4219 before_call = get_last_insn ();
4221 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4222 will set inhibit_defer_pop to that value. */
4223 /* The return type is needed to decide how many bytes the function pops.
4224 Signedness plays no role in that, so for simplicity, we pretend it's
4225 always signed. We also assume that the list of arguments passed has
4226 no impact, so we pretend it is unknown. */
4229 get_identifier (XSTR (orgfun, 0)),
4230 build_function_type (tfom, NULL_TREE),
4231 original_args_size.constant, args_size.constant,
4233 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
4235 old_inhibit_defer_pop + 1, call_fusage, flags, & args_so_far);
4237 /* For calls to `setjmp', etc., inform flow.c it should complain
4238 if nonvolatile values are live. For functions that cannot return,
4239 inform flow that control does not fall through. */
4241 if (flags & (ECF_NORETURN | ECF_LONGJMP))
4243 /* The barrier note must be emitted
4244 immediately after the CALL_INSN. Some ports emit more than
4245 just a CALL_INSN above, so we must search for it here. */
4247 rtx last = get_last_insn ();
4248 while (GET_CODE (last) != CALL_INSN)
4250 last = PREV_INSN (last);
4251 /* There was no CALL_INSN? */
4252 if (last == before_call)
4256 emit_barrier_after (last);
4259 /* Now restore inhibit_defer_pop to its actual original value. */
4262 /* If call is cse'able, make appropriate pair of reg-notes around it.
4263 Test valreg so we don't crash; may safely ignore `const'
4264 if return type is void. Disable for PARALLEL return values, because
4265 we have no way to move such values into a pseudo register. */
4266 if (flags & ECF_LIBCALL_BLOCK)
4272 insns = get_insns ();
4282 if (GET_CODE (valreg) == PARALLEL)
4284 temp = gen_reg_rtx (outmode);
4285 emit_group_store (temp, valreg, NULL_TREE,
4286 GET_MODE_SIZE (outmode));
4290 temp = gen_reg_rtx (GET_MODE (valreg));
4292 /* Construct an "equal form" for the value which mentions all the
4293 arguments in order as well as the function name. */
4294 for (i = 0; i < nargs; i++)
4295 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
4296 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
4298 insns = get_insns ();
4301 if (flags & ECF_PURE)
4302 note = gen_rtx_EXPR_LIST (VOIDmode,
4303 gen_rtx_USE (VOIDmode,
4304 gen_rtx_MEM (BLKmode,
4305 gen_rtx_SCRATCH (VOIDmode))),
4308 emit_libcall_block (insns, temp, valreg, note);
4315 /* Copy the value to the right place. */
4316 if (outmode != VOIDmode && retval)
4322 if (value != mem_value)
4323 emit_move_insn (value, mem_value);
4325 else if (GET_CODE (valreg) == PARALLEL)
4328 value = gen_reg_rtx (outmode);
4329 emit_group_store (value, valreg, NULL_TREE, GET_MODE_SIZE (outmode));
4331 else if (value != 0)
4332 emit_move_insn (value, valreg);
4337 if (ACCUMULATE_OUTGOING_ARGS)
4339 #ifdef REG_PARM_STACK_SPACE
4341 restore_fixed_argument_area (save_area, argblock,
4342 high_to_save, low_to_save);
4345 /* If we saved any argument areas, restore them. */
4346 for (count = 0; count < nargs; count++)
4347 if (argvec[count].save_area)
4349 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4350 rtx adr = plus_constant (argblock,
4351 argvec[count].locate.offset.constant);
4352 rtx stack_area = gen_rtx_MEM (save_mode,
4353 memory_address (save_mode, adr));
4355 if (save_mode == BLKmode)
4356 emit_block_move (stack_area,
4357 validize_mem (argvec[count].save_area),
4358 GEN_INT (argvec[count].locate.size.constant),
4359 BLOCK_OP_CALL_PARM);
4361 emit_move_insn (stack_area, argvec[count].save_area);
4364 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4365 stack_usage_map = initial_stack_usage_map;
4372 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4373 (emitting the queue unless NO_QUEUE is nonzero),
4374 for a value of mode OUTMODE,
4375 with NARGS different arguments, passed as alternating rtx values
4376 and machine_modes to convert them to.
4377 The rtx values should have been passed through protect_from_queue already.
4379 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4380 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4381 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4382 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4383 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4384 or other LCT_ value for other types of library calls. */
4387 emit_library_call (rtx orgfun, enum libcall_type fn_type,
4388 enum machine_mode outmode, int nargs, ...)
4392 va_start (p, nargs);
4393 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4397 /* Like emit_library_call except that an extra argument, VALUE,
4398 comes second and says where to store the result.
4399 (If VALUE is zero, this function chooses a convenient way
4400 to return the value.
4402 This function returns an rtx for where the value is to be found.
4403 If VALUE is nonzero, VALUE is returned. */
4406 emit_library_call_value (rtx orgfun, rtx value,
4407 enum libcall_type fn_type,
4408 enum machine_mode outmode, int nargs, ...)
4413 va_start (p, nargs);
4414 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4421 /* Store a single argument for a function call
4422 into the register or memory area where it must be passed.
4423 *ARG describes the argument value and where to pass it.
4425 ARGBLOCK is the address of the stack-block for all the arguments,
4426 or 0 on a machine where arguments are pushed individually.
4428 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4429 so must be careful about how the stack is used.
4431 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4432 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4433 that we need not worry about saving and restoring the stack.
4435 FNDECL is the declaration of the function we are calling.
4437 Return nonzero if this arg should cause sibcall failure,
4441 store_one_arg (struct arg_data *arg, rtx argblock, int flags,
4442 int variable_size ATTRIBUTE_UNUSED, int reg_parm_stack_space)
4444 tree pval = arg->tree_value;
4448 int i, lower_bound = 0, upper_bound = 0;
4449 int sibcall_failure = 0;
4451 if (TREE_CODE (pval) == ERROR_MARK)
4454 /* Push a new temporary level for any temporaries we make for
4458 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4460 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4461 save any previous data at that location. */
4462 if (argblock && ! variable_size && arg->stack)
4464 #ifdef ARGS_GROW_DOWNWARD
4465 /* stack_slot is negative, but we want to index stack_usage_map
4466 with positive values. */
4467 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4468 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4472 lower_bound = upper_bound - arg->locate.size.constant;
4474 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4475 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4479 upper_bound = lower_bound + arg->locate.size.constant;
4483 /* Don't worry about things in the fixed argument area;
4484 it has already been saved. */
4485 if (i < reg_parm_stack_space)
4486 i = reg_parm_stack_space;
4487 while (i < upper_bound && stack_usage_map[i] == 0)
4490 if (i < upper_bound)
4492 /* We need to make a save area. */
4493 unsigned int size = arg->locate.size.constant * BITS_PER_UNIT;
4494 enum machine_mode save_mode = mode_for_size (size, MODE_INT, 1);
4495 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
4496 rtx stack_area = gen_rtx_MEM (save_mode, adr);
4498 if (save_mode == BLKmode)
4500 tree ot = TREE_TYPE (arg->tree_value);
4501 tree nt = build_qualified_type (ot, (TYPE_QUALS (ot)
4502 | TYPE_QUAL_CONST));
4504 arg->save_area = assign_temp (nt, 0, 1, 1);
4505 preserve_temp_slots (arg->save_area);
4506 emit_block_move (validize_mem (arg->save_area), stack_area,
4507 expr_size (arg->tree_value),
4508 BLOCK_OP_CALL_PARM);
4512 arg->save_area = gen_reg_rtx (save_mode);
4513 emit_move_insn (arg->save_area, stack_area);
4519 /* If this isn't going to be placed on both the stack and in registers,
4520 set up the register and number of words. */
4521 if (! arg->pass_on_stack)
4523 if (flags & ECF_SIBCALL)
4524 reg = arg->tail_call_reg;
4527 partial = arg->partial;
4530 if (reg != 0 && partial == 0)
4531 /* Being passed entirely in a register. We shouldn't be called in
4535 /* If this arg needs special alignment, don't load the registers
4537 if (arg->n_aligned_regs != 0)
4540 /* If this is being passed partially in a register, we can't evaluate
4541 it directly into its stack slot. Otherwise, we can. */
4542 if (arg->value == 0)
4544 /* stack_arg_under_construction is nonzero if a function argument is
4545 being evaluated directly into the outgoing argument list and
4546 expand_call must take special action to preserve the argument list
4547 if it is called recursively.
4549 For scalar function arguments stack_usage_map is sufficient to
4550 determine which stack slots must be saved and restored. Scalar
4551 arguments in general have pass_on_stack == 0.
4553 If this argument is initialized by a function which takes the
4554 address of the argument (a C++ constructor or a C function
4555 returning a BLKmode structure), then stack_usage_map is
4556 insufficient and expand_call must push the stack around the
4557 function call. Such arguments have pass_on_stack == 1.
4559 Note that it is always safe to set stack_arg_under_construction,
4560 but this generates suboptimal code if set when not needed. */
4562 if (arg->pass_on_stack)
4563 stack_arg_under_construction++;
4565 arg->value = expand_expr (pval,
4567 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4568 ? NULL_RTX : arg->stack,
4569 VOIDmode, EXPAND_STACK_PARM);
4571 /* If we are promoting object (or for any other reason) the mode
4572 doesn't agree, convert the mode. */
4574 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4575 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4576 arg->value, arg->unsignedp);
4578 if (arg->pass_on_stack)
4579 stack_arg_under_construction--;
4582 /* Don't allow anything left on stack from computation
4583 of argument to alloca. */
4584 if (flags & ECF_MAY_BE_ALLOCA)
4585 do_pending_stack_adjust ();
4587 if (arg->value == arg->stack)
4588 /* If the value is already in the stack slot, we are done. */
4590 else if (arg->mode != BLKmode)
4594 /* Argument is a scalar, not entirely passed in registers.
4595 (If part is passed in registers, arg->partial says how much
4596 and emit_push_insn will take care of putting it there.)
4598 Push it, and if its size is less than the
4599 amount of space allocated to it,
4600 also bump stack pointer by the additional space.
4601 Note that in C the default argument promotions
4602 will prevent such mismatches. */
4604 size = GET_MODE_SIZE (arg->mode);
4605 /* Compute how much space the push instruction will push.
4606 On many machines, pushing a byte will advance the stack
4607 pointer by a halfword. */
4608 #ifdef PUSH_ROUNDING
4609 size = PUSH_ROUNDING (size);
4613 /* Compute how much space the argument should get:
4614 round up to a multiple of the alignment for arguments. */
4615 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4616 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4617 / (PARM_BOUNDARY / BITS_PER_UNIT))
4618 * (PARM_BOUNDARY / BITS_PER_UNIT));
4620 /* This isn't already where we want it on the stack, so put it there.
4621 This can either be done with push or copy insns. */
4622 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
4623 PARM_BOUNDARY, partial, reg, used - size, argblock,
4624 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4625 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4627 /* Unless this is a partially-in-register argument, the argument is now
4630 arg->value = arg->stack;
4634 /* BLKmode, at least partly to be pushed. */
4636 unsigned int parm_align;
4640 /* Pushing a nonscalar.
4641 If part is passed in registers, PARTIAL says how much
4642 and emit_push_insn will take care of putting it there. */
4644 /* Round its size up to a multiple
4645 of the allocation unit for arguments. */
4647 if (arg->locate.size.var != 0)
4650 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
4654 /* PUSH_ROUNDING has no effect on us, because
4655 emit_push_insn for BLKmode is careful to avoid it. */
4656 if (reg && GET_CODE (reg) == PARALLEL)
4658 /* Use the size of the elt to compute excess. */
4659 rtx elt = XEXP (XVECEXP (reg, 0, 0), 0);
4660 excess = (arg->locate.size.constant
4661 - int_size_in_bytes (TREE_TYPE (pval))
4662 + partial * GET_MODE_SIZE (GET_MODE (elt)));
4665 excess = (arg->locate.size.constant
4666 - int_size_in_bytes (TREE_TYPE (pval))
4667 + partial * UNITS_PER_WORD);
4668 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
4669 NULL_RTX, TYPE_MODE (sizetype), 0);
4672 /* Some types will require stricter alignment, which will be
4673 provided for elsewhere in argument layout. */
4674 parm_align = MAX (PARM_BOUNDARY, TYPE_ALIGN (TREE_TYPE (pval)));
4676 /* When an argument is padded down, the block is aligned to
4677 PARM_BOUNDARY, but the actual argument isn't. */
4678 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4680 if (arg->locate.size.var)
4681 parm_align = BITS_PER_UNIT;
4684 unsigned int excess_align = (excess & -excess) * BITS_PER_UNIT;
4685 parm_align = MIN (parm_align, excess_align);
4689 if ((flags & ECF_SIBCALL) && GET_CODE (arg->value) == MEM)
4691 /* emit_push_insn might not work properly if arg->value and
4692 argblock + arg->locate.offset areas overlap. */
4696 if (XEXP (x, 0) == current_function_internal_arg_pointer
4697 || (GET_CODE (XEXP (x, 0)) == PLUS
4698 && XEXP (XEXP (x, 0), 0) ==
4699 current_function_internal_arg_pointer
4700 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT))
4702 if (XEXP (x, 0) != current_function_internal_arg_pointer)
4703 i = INTVAL (XEXP (XEXP (x, 0), 1));
4705 /* expand_call should ensure this. */
4706 if (arg->locate.offset.var || GET_CODE (size_rtx) != CONST_INT)
4709 if (arg->locate.offset.constant > i)
4711 if (arg->locate.offset.constant < i + INTVAL (size_rtx))
4712 sibcall_failure = 1;
4714 else if (arg->locate.offset.constant < i)
4716 if (i < arg->locate.offset.constant + INTVAL (size_rtx))
4717 sibcall_failure = 1;
4722 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4723 parm_align, partial, reg, excess, argblock,
4724 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4725 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4727 /* Unless this is a partially-in-register argument, the argument is now
4730 ??? Unlike the case above, in which we want the actual
4731 address of the data, so that we can load it directly into a
4732 register, here we want the address of the stack slot, so that
4733 it's properly aligned for word-by-word copying or something
4734 like that. It's not clear that this is always correct. */
4736 arg->value = arg->stack_slot;
4739 /* Mark all slots this store used. */
4740 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
4741 && argblock && ! variable_size && arg->stack)
4742 for (i = lower_bound; i < upper_bound; i++)
4743 stack_usage_map[i] = 1;
4745 /* Once we have pushed something, pops can't safely
4746 be deferred during the rest of the arguments. */
4749 /* ANSI doesn't require a sequence point here,
4750 but PCC has one, so this will avoid some problems. */
4753 /* Free any temporary slots made in processing this argument. Show
4754 that we might have taken the address of something and pushed that
4756 preserve_temp_slots (NULL_RTX);
4760 return sibcall_failure;
4763 /* Nonzero if we do not know how to pass TYPE solely in registers.
4764 We cannot do so in the following cases:
4766 - if the type has variable size
4767 - if the type is marked as addressable (it is required to be constructed
4769 - if the padding and mode of the type is such that a copy into a register
4770 would put it into the wrong part of the register.
4772 Which padding can't be supported depends on the byte endianness.
4774 A value in a register is implicitly padded at the most significant end.
4775 On a big-endian machine, that is the lower end in memory.
4776 So a value padded in memory at the upper end can't go in a register.
4777 For a little-endian machine, the reverse is true. */
4780 default_must_pass_in_stack (enum machine_mode mode, tree type)
4785 /* If the type has variable size... */
4786 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4789 /* If the type is marked as addressable (it is required
4790 to be constructed into the stack)... */
4791 if (TREE_ADDRESSABLE (type))
4794 /* If the padding and mode of the type is such that a copy into
4795 a register would put it into the wrong part of the register. */
4797 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
4798 && (FUNCTION_ARG_PADDING (mode, type)
4799 == (BYTES_BIG_ENDIAN ? upward : downward)))