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;
661 /* Return nonzero when tree represent call to longjmp. */
664 setjmp_call_p (tree fndecl)
666 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
669 /* Return true when exp contains alloca call. */
671 alloca_call_p (tree exp)
673 if (TREE_CODE (exp) == CALL_EXPR
674 && TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
675 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
677 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
678 0) & ECF_MAY_BE_ALLOCA))
683 /* Detect flags (function attributes) from the function decl or type node. */
686 flags_from_decl_or_type (tree exp)
693 struct cgraph_rtl_info *i = cgraph_rtl_info (exp);
694 type = TREE_TYPE (exp);
698 if (i->pure_function)
699 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
700 if (i->const_function)
701 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
704 /* The function exp may have the `malloc' attribute. */
705 if (DECL_IS_MALLOC (exp))
708 /* The function exp may have the `pure' attribute. */
709 if (DECL_IS_PURE (exp))
710 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
712 if (TREE_NOTHROW (exp))
713 flags |= ECF_NOTHROW;
715 if (TREE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
716 flags |= ECF_LIBCALL_BLOCK | ECF_CONST;
718 else if (TYPE_P (exp) && TYPE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
721 if (TREE_THIS_VOLATILE (exp))
722 flags |= ECF_NORETURN;
724 /* Mark if the function returns with the stack pointer depressed. We
725 cannot consider it pure or constant in that case. */
726 if (TREE_CODE (type) == FUNCTION_TYPE && TYPE_RETURNS_STACK_DEPRESSED (type))
728 flags |= ECF_SP_DEPRESSED;
729 flags &= ~(ECF_PURE | ECF_CONST | ECF_LIBCALL_BLOCK);
735 /* Detect flags from a CALL_EXPR. */
738 call_expr_flags (tree t)
741 tree decl = get_callee_fndecl (t);
744 flags = flags_from_decl_or_type (decl);
747 t = TREE_TYPE (TREE_OPERAND (t, 0));
748 if (t && TREE_CODE (t) == POINTER_TYPE)
749 flags = flags_from_decl_or_type (TREE_TYPE (t));
757 /* Precompute all register parameters as described by ARGS, storing values
758 into fields within the ARGS array.
760 NUM_ACTUALS indicates the total number elements in the ARGS array.
762 Set REG_PARM_SEEN if we encounter a register parameter. */
765 precompute_register_parameters (int num_actuals, struct arg_data *args, int *reg_parm_seen)
771 for (i = 0; i < num_actuals; i++)
772 if (args[i].reg != 0 && ! args[i].pass_on_stack)
776 if (args[i].value == 0)
779 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
781 preserve_temp_slots (args[i].value);
784 /* ANSI doesn't require a sequence point here,
785 but PCC has one, so this will avoid some problems. */
789 /* If the value is a non-legitimate constant, force it into a
790 pseudo now. TLS symbols sometimes need a call to resolve. */
791 if (CONSTANT_P (args[i].value)
792 && !LEGITIMATE_CONSTANT_P (args[i].value))
793 args[i].value = force_reg (args[i].mode, args[i].value);
795 /* If we are to promote the function arg to a wider mode,
798 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
800 = convert_modes (args[i].mode,
801 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
802 args[i].value, args[i].unsignedp);
804 /* If the value is expensive, and we are inside an appropriately
805 short loop, put the value into a pseudo and then put the pseudo
808 For small register classes, also do this if this call uses
809 register parameters. This is to avoid reload conflicts while
810 loading the parameters registers. */
812 if ((! (GET_CODE (args[i].value) == REG
813 || (GET_CODE (args[i].value) == SUBREG
814 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
815 && args[i].mode != BLKmode
816 && rtx_cost (args[i].value, SET) > COSTS_N_INSNS (1)
817 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
818 || preserve_subexpressions_p ()))
819 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
823 #ifdef REG_PARM_STACK_SPACE
825 /* The argument list is the property of the called routine and it
826 may clobber it. If the fixed area has been used for previous
827 parameters, we must save and restore it. */
830 save_fixed_argument_area (int reg_parm_stack_space, rtx argblock, int *low_to_save, int *high_to_save)
835 /* Compute the boundary of the area that needs to be saved, if any. */
836 high = reg_parm_stack_space;
837 #ifdef ARGS_GROW_DOWNWARD
840 if (high > highest_outgoing_arg_in_use)
841 high = highest_outgoing_arg_in_use;
843 for (low = 0; low < high; low++)
844 if (stack_usage_map[low] != 0)
847 enum machine_mode save_mode;
852 while (stack_usage_map[--high] == 0)
856 *high_to_save = high;
858 num_to_save = high - low + 1;
859 save_mode = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
861 /* If we don't have the required alignment, must do this
863 if ((low & (MIN (GET_MODE_SIZE (save_mode),
864 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
867 #ifdef ARGS_GROW_DOWNWARD
872 stack_area = gen_rtx_MEM (save_mode,
873 memory_address (save_mode,
874 plus_constant (argblock,
877 set_mem_align (stack_area, PARM_BOUNDARY);
878 if (save_mode == BLKmode)
880 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
881 emit_block_move (validize_mem (save_area), stack_area,
882 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
886 save_area = gen_reg_rtx (save_mode);
887 emit_move_insn (save_area, stack_area);
897 restore_fixed_argument_area (rtx save_area, rtx argblock, int high_to_save, int low_to_save)
899 enum machine_mode save_mode = GET_MODE (save_area);
903 #ifdef ARGS_GROW_DOWNWARD
904 delta = -high_to_save;
908 stack_area = gen_rtx_MEM (save_mode,
909 memory_address (save_mode,
910 plus_constant (argblock, delta)));
911 set_mem_align (stack_area, PARM_BOUNDARY);
913 if (save_mode != BLKmode)
914 emit_move_insn (stack_area, save_area);
916 emit_block_move (stack_area, validize_mem (save_area),
917 GEN_INT (high_to_save - low_to_save + 1),
920 #endif /* REG_PARM_STACK_SPACE */
922 /* If any elements in ARGS refer to parameters that are to be passed in
923 registers, but not in memory, and whose alignment does not permit a
924 direct copy into registers. Copy the values into a group of pseudos
925 which we will later copy into the appropriate hard registers.
927 Pseudos for each unaligned argument will be stored into the array
928 args[argnum].aligned_regs. The caller is responsible for deallocating
929 the aligned_regs array if it is nonzero. */
932 store_unaligned_arguments_into_pseudos (struct arg_data *args, int num_actuals)
936 for (i = 0; i < num_actuals; i++)
937 if (args[i].reg != 0 && ! args[i].pass_on_stack
938 && args[i].mode == BLKmode
939 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
940 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
942 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
943 int nregs = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
944 int endian_correction = 0;
946 args[i].n_aligned_regs = args[i].partial ? args[i].partial : nregs;
947 args[i].aligned_regs = xmalloc (sizeof (rtx) * args[i].n_aligned_regs);
949 /* Structures smaller than a word are normally aligned to the
950 least significant byte. On a BYTES_BIG_ENDIAN machine,
951 this means we must skip the empty high order bytes when
952 calculating the bit offset. */
953 if (bytes < UNITS_PER_WORD
954 #ifdef BLOCK_REG_PADDING
955 && (BLOCK_REG_PADDING (args[i].mode,
956 TREE_TYPE (args[i].tree_value), 1)
962 endian_correction = BITS_PER_WORD - bytes * BITS_PER_UNIT;
964 for (j = 0; j < args[i].n_aligned_regs; j++)
966 rtx reg = gen_reg_rtx (word_mode);
967 rtx word = operand_subword_force (args[i].value, j, BLKmode);
968 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
970 args[i].aligned_regs[j] = reg;
971 word = extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
972 word_mode, word_mode, BITS_PER_WORD);
974 /* There is no need to restrict this code to loading items
975 in TYPE_ALIGN sized hunks. The bitfield instructions can
976 load up entire word sized registers efficiently.
978 ??? This may not be needed anymore.
979 We use to emit a clobber here but that doesn't let later
980 passes optimize the instructions we emit. By storing 0 into
981 the register later passes know the first AND to zero out the
982 bitfield being set in the register is unnecessary. The store
983 of 0 will be deleted as will at least the first AND. */
985 emit_move_insn (reg, const0_rtx);
987 bytes -= bitsize / BITS_PER_UNIT;
988 store_bit_field (reg, bitsize, endian_correction, word_mode,
989 word, BITS_PER_WORD);
994 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
997 NUM_ACTUALS is the total number of parameters.
999 N_NAMED_ARGS is the total number of named arguments.
1001 FNDECL is the tree code for the target of this call (if known)
1003 ARGS_SO_FAR holds state needed by the target to know where to place
1006 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1007 for arguments which are passed in registers.
1009 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1010 and may be modified by this routine.
1012 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1013 flags which may may be modified by this routine.
1015 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1016 the thunked-to function. */
1019 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
1020 struct arg_data *args,
1021 struct args_size *args_size,
1022 int n_named_args ATTRIBUTE_UNUSED,
1023 tree actparms, tree fndecl,
1024 CUMULATIVE_ARGS *args_so_far,
1025 int reg_parm_stack_space,
1026 rtx *old_stack_level, int *old_pending_adj,
1027 int *must_preallocate, int *ecf_flags,
1028 bool call_from_thunk_p)
1030 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1033 /* Count arg position in order args appear. */
1039 args_size->constant = 0;
1042 /* In this loop, we consider args in the order they are written.
1043 We fill up ARGS from the front or from the back if necessary
1044 so that in any case the first arg to be pushed ends up at the front. */
1046 if (PUSH_ARGS_REVERSED)
1048 i = num_actuals - 1, inc = -1;
1049 /* In this case, must reverse order of args
1050 so that we compute and push the last arg first. */
1057 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1058 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1060 tree type = TREE_TYPE (TREE_VALUE (p));
1062 enum machine_mode mode;
1064 args[i].tree_value = TREE_VALUE (p);
1066 /* Replace erroneous argument with constant zero. */
1067 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1068 args[i].tree_value = integer_zero_node, type = integer_type_node;
1070 /* If TYPE is a transparent union, pass things the way we would
1071 pass the first field of the union. We have already verified that
1072 the modes are the same. */
1073 if (TREE_CODE (type) == UNION_TYPE && TYPE_TRANSPARENT_UNION (type))
1074 type = TREE_TYPE (TYPE_FIELDS (type));
1076 /* Decide where to pass this arg.
1078 args[i].reg is nonzero if all or part is passed in registers.
1080 args[i].partial is nonzero if part but not all is passed in registers,
1081 and the exact value says how many words are passed in registers.
1083 args[i].pass_on_stack is nonzero if the argument must at least be
1084 computed on the stack. It may then be loaded back into registers
1085 if args[i].reg is nonzero.
1087 These decisions are driven by the FUNCTION_... macros and must agree
1088 with those made by function.c. */
1090 /* See if this argument should be passed by invisible reference. */
1091 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (type))
1092 || TREE_ADDRESSABLE (type)
1093 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1094 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
1095 type, argpos < n_named_args)
1099 /* If we're compiling a thunk, pass through invisible
1100 references instead of making a copy. */
1101 if (call_from_thunk_p
1102 #ifdef FUNCTION_ARG_CALLEE_COPIES
1103 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
1104 type, argpos < n_named_args)
1105 /* If it's in a register, we must make a copy of it too. */
1106 /* ??? Is this a sufficient test? Is there a better one? */
1107 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1108 && REG_P (DECL_RTL (args[i].tree_value)))
1109 && ! TREE_ADDRESSABLE (type))
1113 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1114 new object from the argument. If we are passing by
1115 invisible reference, the callee will do that for us, so we
1116 can strip off the TARGET_EXPR. This is not always safe,
1117 but it is safe in the only case where this is a useful
1118 optimization; namely, when the argument is a plain object.
1119 In that case, the frontend is just asking the backend to
1120 make a bitwise copy of the argument. */
1122 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
1123 && (DECL_P (TREE_OPERAND (args[i].tree_value, 1)))
1124 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
1125 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
1127 args[i].tree_value = build1 (ADDR_EXPR,
1128 build_pointer_type (type),
1129 args[i].tree_value);
1130 type = build_pointer_type (type);
1132 else if (TREE_CODE (args[i].tree_value) == TARGET_EXPR)
1134 /* In the V3 C++ ABI, parameters are destroyed in the caller.
1135 We implement this by passing the address of the temporary
1136 rather than expanding it into another allocated slot. */
1137 args[i].tree_value = build1 (ADDR_EXPR,
1138 build_pointer_type (type),
1139 args[i].tree_value);
1140 type = build_pointer_type (type);
1144 /* We make a copy of the object and pass the address to the
1145 function being called. */
1148 if (!COMPLETE_TYPE_P (type)
1149 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1150 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1151 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1152 STACK_CHECK_MAX_VAR_SIZE))))
1154 /* This is a variable-sized object. Make space on the stack
1156 rtx size_rtx = expr_size (TREE_VALUE (p));
1158 if (*old_stack_level == 0)
1160 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1161 *old_pending_adj = pending_stack_adjust;
1162 pending_stack_adjust = 0;
1165 copy = gen_rtx_MEM (BLKmode,
1166 allocate_dynamic_stack_space
1167 (size_rtx, NULL_RTX, TYPE_ALIGN (type)));
1168 set_mem_attributes (copy, type, 1);
1171 copy = assign_temp (type, 0, 1, 0);
1173 store_expr (args[i].tree_value, copy, 0);
1174 *ecf_flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
1176 args[i].tree_value = build1 (ADDR_EXPR,
1177 build_pointer_type (type),
1178 make_tree (type, copy));
1179 type = build_pointer_type (type);
1183 mode = TYPE_MODE (type);
1184 unsignedp = TYPE_UNSIGNED (type);
1186 if (targetm.calls.promote_function_args (fndecl ? TREE_TYPE (fndecl) : 0))
1187 mode = promote_mode (type, mode, &unsignedp, 1);
1189 args[i].unsignedp = unsignedp;
1190 args[i].mode = mode;
1192 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1193 argpos < n_named_args);
1194 #ifdef FUNCTION_INCOMING_ARG
1195 /* If this is a sibling call and the machine has register windows, the
1196 register window has to be unwinded before calling the routine, so
1197 arguments have to go into the incoming registers. */
1198 args[i].tail_call_reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1199 argpos < n_named_args);
1201 args[i].tail_call_reg = args[i].reg;
1204 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1207 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1208 argpos < n_named_args);
1211 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1213 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1214 it means that we are to pass this arg in the register(s) designated
1215 by the PARALLEL, but also to pass it in the stack. */
1216 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1217 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1218 args[i].pass_on_stack = 1;
1220 /* If this is an addressable type, we must preallocate the stack
1221 since we must evaluate the object into its final location.
1223 If this is to be passed in both registers and the stack, it is simpler
1225 if (TREE_ADDRESSABLE (type)
1226 || (args[i].pass_on_stack && args[i].reg != 0))
1227 *must_preallocate = 1;
1229 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1230 we cannot consider this function call constant. */
1231 if (TREE_ADDRESSABLE (type))
1232 *ecf_flags &= ~ECF_LIBCALL_BLOCK;
1234 /* Compute the stack-size of this argument. */
1235 if (args[i].reg == 0 || args[i].partial != 0
1236 || reg_parm_stack_space > 0
1237 || args[i].pass_on_stack)
1238 locate_and_pad_parm (mode, type,
1239 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1244 args[i].pass_on_stack ? 0 : args[i].partial,
1245 fndecl, args_size, &args[i].locate);
1246 #ifdef BLOCK_REG_PADDING
1248 /* The argument is passed entirely in registers. See at which
1249 end it should be padded. */
1250 args[i].locate.where_pad =
1251 BLOCK_REG_PADDING (mode, type,
1252 int_size_in_bytes (type) <= UNITS_PER_WORD);
1255 /* Update ARGS_SIZE, the total stack space for args so far. */
1257 args_size->constant += args[i].locate.size.constant;
1258 if (args[i].locate.size.var)
1259 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
1261 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1262 have been used, etc. */
1264 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1265 argpos < n_named_args);
1269 /* Update ARGS_SIZE to contain the total size for the argument block.
1270 Return the original constant component of the argument block's size.
1272 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1273 for arguments passed in registers. */
1276 compute_argument_block_size (int reg_parm_stack_space,
1277 struct args_size *args_size,
1278 int preferred_stack_boundary ATTRIBUTE_UNUSED)
1280 int unadjusted_args_size = args_size->constant;
1282 /* For accumulate outgoing args mode we don't need to align, since the frame
1283 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1284 backends from generating misaligned frame sizes. */
1285 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1286 preferred_stack_boundary = STACK_BOUNDARY;
1288 /* Compute the actual size of the argument block required. The variable
1289 and constant sizes must be combined, the size may have to be rounded,
1290 and there may be a minimum required size. */
1294 args_size->var = ARGS_SIZE_TREE (*args_size);
1295 args_size->constant = 0;
1297 preferred_stack_boundary /= BITS_PER_UNIT;
1298 if (preferred_stack_boundary > 1)
1300 /* We don't handle this case yet. To handle it correctly we have
1301 to add the delta, round and subtract the delta.
1302 Currently no machine description requires this support. */
1303 if (stack_pointer_delta & (preferred_stack_boundary - 1))
1305 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1308 if (reg_parm_stack_space > 0)
1311 = size_binop (MAX_EXPR, args_size->var,
1312 ssize_int (reg_parm_stack_space));
1314 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1315 /* The area corresponding to register parameters is not to count in
1316 the size of the block we need. So make the adjustment. */
1318 = size_binop (MINUS_EXPR, args_size->var,
1319 ssize_int (reg_parm_stack_space));
1325 preferred_stack_boundary /= BITS_PER_UNIT;
1326 if (preferred_stack_boundary < 1)
1327 preferred_stack_boundary = 1;
1328 args_size->constant = (((args_size->constant
1329 + stack_pointer_delta
1330 + preferred_stack_boundary - 1)
1331 / preferred_stack_boundary
1332 * preferred_stack_boundary)
1333 - stack_pointer_delta);
1335 args_size->constant = MAX (args_size->constant,
1336 reg_parm_stack_space);
1338 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1339 args_size->constant -= reg_parm_stack_space;
1342 return unadjusted_args_size;
1345 /* Precompute parameters as needed for a function call.
1347 FLAGS is mask of ECF_* constants.
1349 NUM_ACTUALS is the number of arguments.
1351 ARGS is an array containing information for each argument; this
1352 routine fills in the INITIAL_VALUE and VALUE fields for each
1353 precomputed argument. */
1356 precompute_arguments (int flags, int num_actuals, struct arg_data *args)
1360 /* If this is a libcall, then precompute all arguments so that we do not
1361 get extraneous instructions emitted as part of the libcall sequence.
1363 If this target defines ACCUMULATE_OUTGOING_ARGS to true, then we must
1364 precompute all arguments that contain function calls. Otherwise,
1365 computing arguments for a subcall may clobber arguments for this call.
1367 If this target defines ACCUMULATE_OUTGOING_ARGS to false, then we only
1368 need to precompute arguments that change the stack pointer, such as calls
1369 to alloca, and calls that do not pop all of their arguments. */
1371 for (i = 0; i < num_actuals; i++)
1372 if ((flags & ECF_LIBCALL_BLOCK)
1373 || calls_function (args[i].tree_value, !ACCUMULATE_OUTGOING_ARGS))
1375 enum machine_mode mode;
1377 /* If this is an addressable type, we cannot pre-evaluate it. */
1378 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1382 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1384 /* ANSI doesn't require a sequence point here,
1385 but PCC has one, so this will avoid some problems. */
1388 args[i].initial_value = args[i].value
1389 = protect_from_queue (args[i].value, 0);
1391 mode = TYPE_MODE (TREE_TYPE (args[i].tree_value));
1392 if (mode != args[i].mode)
1395 = convert_modes (args[i].mode, mode,
1396 args[i].value, args[i].unsignedp);
1397 #ifdef PROMOTE_FOR_CALL_ONLY
1398 /* CSE will replace this only if it contains args[i].value
1399 pseudo, so convert it down to the declared mode using
1401 if (GET_CODE (args[i].value) == REG
1402 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1404 args[i].initial_value
1405 = gen_lowpart_SUBREG (mode, args[i].value);
1406 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1407 SUBREG_PROMOTED_UNSIGNED_SET (args[i].initial_value,
1415 /* Given the current state of MUST_PREALLOCATE and information about
1416 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1417 compute and return the final value for MUST_PREALLOCATE. */
1420 finalize_must_preallocate (int must_preallocate, int num_actuals, struct arg_data *args, struct args_size *args_size)
1422 /* See if we have or want to preallocate stack space.
1424 If we would have to push a partially-in-regs parm
1425 before other stack parms, preallocate stack space instead.
1427 If the size of some parm is not a multiple of the required stack
1428 alignment, we must preallocate.
1430 If the total size of arguments that would otherwise create a copy in
1431 a temporary (such as a CALL) is more than half the total argument list
1432 size, preallocation is faster.
1434 Another reason to preallocate is if we have a machine (like the m88k)
1435 where stack alignment is required to be maintained between every
1436 pair of insns, not just when the call is made. However, we assume here
1437 that such machines either do not have push insns (and hence preallocation
1438 would occur anyway) or the problem is taken care of with
1441 if (! must_preallocate)
1443 int partial_seen = 0;
1444 int copy_to_evaluate_size = 0;
1447 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1449 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1451 else if (partial_seen && args[i].reg == 0)
1452 must_preallocate = 1;
1454 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1455 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1456 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1457 || TREE_CODE (args[i].tree_value) == COND_EXPR
1458 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1459 copy_to_evaluate_size
1460 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1463 if (copy_to_evaluate_size * 2 >= args_size->constant
1464 && args_size->constant > 0)
1465 must_preallocate = 1;
1467 return must_preallocate;
1470 /* If we preallocated stack space, compute the address of each argument
1471 and store it into the ARGS array.
1473 We need not ensure it is a valid memory address here; it will be
1474 validized when it is used.
1476 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1479 compute_argument_addresses (struct arg_data *args, rtx argblock, int num_actuals)
1483 rtx arg_reg = argblock;
1484 int i, arg_offset = 0;
1486 if (GET_CODE (argblock) == PLUS)
1487 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1489 for (i = 0; i < num_actuals; i++)
1491 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
1492 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
1495 /* Skip this parm if it will not be passed on the stack. */
1496 if (! args[i].pass_on_stack && args[i].reg != 0)
1499 if (GET_CODE (offset) == CONST_INT)
1500 addr = plus_constant (arg_reg, INTVAL (offset));
1502 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1504 addr = plus_constant (addr, arg_offset);
1505 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1506 set_mem_align (args[i].stack, PARM_BOUNDARY);
1507 set_mem_attributes (args[i].stack,
1508 TREE_TYPE (args[i].tree_value), 1);
1510 if (GET_CODE (slot_offset) == CONST_INT)
1511 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1513 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1515 addr = plus_constant (addr, arg_offset);
1516 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1517 set_mem_align (args[i].stack_slot, PARM_BOUNDARY);
1518 set_mem_attributes (args[i].stack_slot,
1519 TREE_TYPE (args[i].tree_value), 1);
1521 /* Function incoming arguments may overlap with sibling call
1522 outgoing arguments and we cannot allow reordering of reads
1523 from function arguments with stores to outgoing arguments
1524 of sibling calls. */
1525 set_mem_alias_set (args[i].stack, 0);
1526 set_mem_alias_set (args[i].stack_slot, 0);
1531 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1532 in a call instruction.
1534 FNDECL is the tree node for the target function. For an indirect call
1535 FNDECL will be NULL_TREE.
1537 ADDR is the operand 0 of CALL_EXPR for this call. */
1540 rtx_for_function_call (tree fndecl, tree addr)
1544 /* Get the function to call, in the form of RTL. */
1547 /* If this is the first use of the function, see if we need to
1548 make an external definition for it. */
1549 if (! TREE_USED (fndecl))
1551 assemble_external (fndecl);
1552 TREE_USED (fndecl) = 1;
1555 /* Get a SYMBOL_REF rtx for the function address. */
1556 funexp = XEXP (DECL_RTL (fndecl), 0);
1559 /* Generate an rtx (probably a pseudo-register) for the address. */
1562 funexp = expand_expr (addr, NULL_RTX, VOIDmode, 0);
1563 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1569 /* Do the register loads required for any wholly-register parms or any
1570 parms which are passed both on the stack and in a register. Their
1571 expressions were already evaluated.
1573 Mark all register-parms as living through the call, putting these USE
1574 insns in the CALL_INSN_FUNCTION_USAGE field.
1576 When IS_SIBCALL, perform the check_sibcall_overlap_argument_overlap
1577 checking, setting *SIBCALL_FAILURE if appropriate. */
1580 load_register_parameters (struct arg_data *args, int num_actuals,
1581 rtx *call_fusage, int flags, int is_sibcall,
1582 int *sibcall_failure)
1586 for (i = 0; i < num_actuals; i++)
1588 rtx reg = ((flags & ECF_SIBCALL)
1589 ? args[i].tail_call_reg : args[i].reg);
1592 int partial = args[i].partial;
1595 rtx before_arg = get_last_insn ();
1596 /* Set to non-negative if must move a word at a time, even if just
1597 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1598 we just use a normal move insn. This value can be zero if the
1599 argument is a zero size structure with no fields. */
1603 else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
1605 size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1606 nregs = (size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1609 size = GET_MODE_SIZE (args[i].mode);
1611 /* Handle calls that pass values in multiple non-contiguous
1612 locations. The Irix 6 ABI has examples of this. */
1614 if (GET_CODE (reg) == PARALLEL)
1616 tree type = TREE_TYPE (args[i].tree_value);
1617 emit_group_load (reg, args[i].value, type,
1618 int_size_in_bytes (type));
1621 /* If simple case, just do move. If normal partial, store_one_arg
1622 has already loaded the register for us. In all other cases,
1623 load the register(s) from memory. */
1625 else if (nregs == -1)
1627 emit_move_insn (reg, args[i].value);
1628 #ifdef BLOCK_REG_PADDING
1629 /* Handle case where we have a value that needs shifting
1630 up to the msb. eg. a QImode value and we're padding
1631 upward on a BYTES_BIG_ENDIAN machine. */
1632 if (size < UNITS_PER_WORD
1633 && (args[i].locate.where_pad
1634 == (BYTES_BIG_ENDIAN ? upward : downward)))
1637 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
1639 /* Assigning REG here rather than a temp makes CALL_FUSAGE
1640 report the whole reg as used. Strictly speaking, the
1641 call only uses SIZE bytes at the msb end, but it doesn't
1642 seem worth generating rtl to say that. */
1643 reg = gen_rtx_REG (word_mode, REGNO (reg));
1644 x = expand_binop (word_mode, ashl_optab, reg,
1645 GEN_INT (shift), reg, 1, OPTAB_WIDEN);
1647 emit_move_insn (reg, x);
1652 /* If we have pre-computed the values to put in the registers in
1653 the case of non-aligned structures, copy them in now. */
1655 else if (args[i].n_aligned_regs != 0)
1656 for (j = 0; j < args[i].n_aligned_regs; j++)
1657 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1658 args[i].aligned_regs[j]);
1660 else if (partial == 0 || args[i].pass_on_stack)
1662 rtx mem = validize_mem (args[i].value);
1664 /* Handle a BLKmode that needs shifting. */
1665 if (nregs == 1 && size < UNITS_PER_WORD
1666 #ifdef BLOCK_REG_PADDING
1667 && args[i].locate.where_pad == downward
1673 rtx tem = operand_subword_force (mem, 0, args[i].mode);
1674 rtx ri = gen_rtx_REG (word_mode, REGNO (reg));
1675 rtx x = gen_reg_rtx (word_mode);
1676 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
1677 optab dir = BYTES_BIG_ENDIAN ? lshr_optab : ashl_optab;
1679 emit_move_insn (x, tem);
1680 x = expand_binop (word_mode, dir, x, GEN_INT (shift),
1681 ri, 1, OPTAB_WIDEN);
1683 emit_move_insn (ri, x);
1686 move_block_to_reg (REGNO (reg), mem, nregs, args[i].mode);
1689 /* When a parameter is a block, and perhaps in other cases, it is
1690 possible that it did a load from an argument slot that was
1691 already clobbered. */
1693 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
1694 *sibcall_failure = 1;
1696 /* Handle calls that pass values in multiple non-contiguous
1697 locations. The Irix 6 ABI has examples of this. */
1698 if (GET_CODE (reg) == PARALLEL)
1699 use_group_regs (call_fusage, reg);
1700 else if (nregs == -1)
1701 use_reg (call_fusage, reg);
1703 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1708 /* Try to integrate function. See expand_inline_function for documentation
1709 about the parameters. */
1712 try_to_integrate (tree fndecl, tree actparms, rtx target, int ignore,
1713 tree type, rtx structure_value_addr)
1718 rtx old_stack_level = 0;
1719 int reg_parm_stack_space = 0;
1721 #ifdef REG_PARM_STACK_SPACE
1722 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1725 before_call = get_last_insn ();
1727 timevar_push (TV_INTEGRATION);
1729 temp = expand_inline_function (fndecl, actparms, target,
1731 structure_value_addr);
1733 timevar_pop (TV_INTEGRATION);
1735 /* If inlining succeeded, return. */
1736 if (temp != (rtx) (size_t) - 1)
1738 if (ACCUMULATE_OUTGOING_ARGS)
1740 /* If the outgoing argument list must be preserved, push
1741 the stack before executing the inlined function if it
1744 i = reg_parm_stack_space;
1745 if (i > highest_outgoing_arg_in_use)
1746 i = highest_outgoing_arg_in_use;
1747 while (--i >= 0 && stack_usage_map[i] == 0)
1750 if (stack_arg_under_construction || i >= 0)
1753 = before_call ? NEXT_INSN (before_call) : get_insns ();
1754 rtx insn = NULL_RTX, seq;
1756 /* Look for a call in the inline function code.
1757 If DECL_STRUCT_FUNCTION (fndecl)->outgoing_args_size is
1758 nonzero then there is a call and it is not necessary
1759 to scan the insns. */
1761 if (DECL_STRUCT_FUNCTION (fndecl)->outgoing_args_size == 0)
1762 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1763 if (GET_CODE (insn) == CALL_INSN)
1768 /* Reserve enough stack space so that the largest
1769 argument list of any function call in the inline
1770 function does not overlap the argument list being
1771 evaluated. This is usually an overestimate because
1772 allocate_dynamic_stack_space reserves space for an
1773 outgoing argument list in addition to the requested
1774 space, but there is no way to ask for stack space such
1775 that an argument list of a certain length can be
1778 Add the stack space reserved for register arguments, if
1779 any, in the inline function. What is really needed is the
1780 largest value of reg_parm_stack_space in the inline
1781 function, but that is not available. Using the current
1782 value of reg_parm_stack_space is wrong, but gives
1783 correct results on all supported machines. */
1786 (DECL_STRUCT_FUNCTION (fndecl)->outgoing_args_size
1787 + reg_parm_stack_space);
1790 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1791 allocate_dynamic_stack_space (GEN_INT (adjust),
1792 NULL_RTX, BITS_PER_UNIT);
1795 emit_insn_before (seq, first_insn);
1796 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1801 /* If the result is equivalent to TARGET, return TARGET to simplify
1802 checks in store_expr. They can be equivalent but not equal in the
1803 case of a function that returns BLKmode. */
1804 if (temp != target && rtx_equal_p (temp, target))
1809 /* If inlining failed, mark FNDECL as needing to be compiled
1810 separately after all. If function was declared inline,
1812 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1813 && optimize > 0 && !TREE_ADDRESSABLE (fndecl))
1815 warning ("%Jinlining failed in call to '%F'", fndecl, fndecl);
1816 warning ("called from here");
1818 lang_hooks.mark_addressable (fndecl);
1819 return (rtx) (size_t) - 1;
1822 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1823 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1824 bytes, then we would need to push some additional bytes to pad the
1825 arguments. So, we compute an adjust to the stack pointer for an
1826 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1827 bytes. Then, when the arguments are pushed the stack will be perfectly
1828 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1829 be popped after the call. Returns the adjustment. */
1832 combine_pending_stack_adjustment_and_call (int unadjusted_args_size,
1833 struct args_size *args_size,
1834 int preferred_unit_stack_boundary)
1836 /* The number of bytes to pop so that the stack will be
1837 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1838 HOST_WIDE_INT adjustment;
1839 /* The alignment of the stack after the arguments are pushed, if we
1840 just pushed the arguments without adjust the stack here. */
1841 HOST_WIDE_INT unadjusted_alignment;
1843 unadjusted_alignment
1844 = ((stack_pointer_delta + unadjusted_args_size)
1845 % preferred_unit_stack_boundary);
1847 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1848 as possible -- leaving just enough left to cancel out the
1849 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1850 PENDING_STACK_ADJUST is non-negative, and congruent to
1851 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1853 /* Begin by trying to pop all the bytes. */
1854 unadjusted_alignment
1855 = (unadjusted_alignment
1856 - (pending_stack_adjust % preferred_unit_stack_boundary));
1857 adjustment = pending_stack_adjust;
1858 /* Push enough additional bytes that the stack will be aligned
1859 after the arguments are pushed. */
1860 if (preferred_unit_stack_boundary > 1)
1862 if (unadjusted_alignment > 0)
1863 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1865 adjustment += unadjusted_alignment;
1868 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1869 bytes after the call. The right number is the entire
1870 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1871 by the arguments in the first place. */
1873 = pending_stack_adjust - adjustment + unadjusted_args_size;
1878 /* Scan X expression if it does not dereference any argument slots
1879 we already clobbered by tail call arguments (as noted in stored_args_map
1881 Return nonzero if X expression dereferences such argument slots,
1885 check_sibcall_argument_overlap_1 (rtx x)
1895 code = GET_CODE (x);
1899 if (XEXP (x, 0) == current_function_internal_arg_pointer)
1901 else if (GET_CODE (XEXP (x, 0)) == PLUS
1902 && XEXP (XEXP (x, 0), 0) ==
1903 current_function_internal_arg_pointer
1904 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
1905 i = INTVAL (XEXP (XEXP (x, 0), 1));
1909 #ifdef ARGS_GROW_DOWNWARD
1910 i = -i - GET_MODE_SIZE (GET_MODE (x));
1913 for (k = 0; k < GET_MODE_SIZE (GET_MODE (x)); k++)
1914 if (i + k < stored_args_map->n_bits
1915 && TEST_BIT (stored_args_map, i + k))
1921 /* Scan all subexpressions. */
1922 fmt = GET_RTX_FORMAT (code);
1923 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
1927 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
1930 else if (*fmt == 'E')
1932 for (j = 0; j < XVECLEN (x, i); j++)
1933 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
1940 /* Scan sequence after INSN if it does not dereference any argument slots
1941 we already clobbered by tail call arguments (as noted in stored_args_map
1942 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
1943 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
1944 should be 0). Return nonzero if sequence after INSN dereferences such argument
1945 slots, zero otherwise. */
1948 check_sibcall_argument_overlap (rtx insn, struct arg_data *arg, int mark_stored_args_map)
1952 if (insn == NULL_RTX)
1953 insn = get_insns ();
1955 insn = NEXT_INSN (insn);
1957 for (; insn; insn = NEXT_INSN (insn))
1959 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
1962 if (mark_stored_args_map)
1964 #ifdef ARGS_GROW_DOWNWARD
1965 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
1967 low = arg->locate.slot_offset.constant;
1970 for (high = low + arg->locate.size.constant; low < high; low++)
1971 SET_BIT (stored_args_map, low);
1973 return insn != NULL_RTX;
1977 fix_unsafe_tree (tree t)
1979 switch (unsafe_for_reeval (t))
1984 case 1: /* Mildly unsafe. */
1985 t = unsave_expr (t);
1988 case 2: /* Wildly unsafe. */
1990 tree var = build_decl (VAR_DECL, NULL_TREE,
1993 expand_expr (t, NULL_RTX, VOIDmode, EXPAND_NORMAL));
2005 /* If function value *VALUE was returned at the most significant end of a
2006 register, shift it towards the least significant end and convert it to
2007 TYPE's mode. Return true and update *VALUE if some action was needed.
2009 TYPE is the type of the function's return value, which is known not
2010 to have mode BLKmode. */
2013 shift_returned_value (tree type, rtx *value)
2015 if (targetm.calls.return_in_msb (type))
2017 HOST_WIDE_INT shift;
2019 shift = (GET_MODE_BITSIZE (GET_MODE (*value))
2020 - BITS_PER_UNIT * int_size_in_bytes (type));
2023 *value = expand_binop (GET_MODE (*value), lshr_optab, *value,
2024 GEN_INT (shift), 0, 1, OPTAB_WIDEN);
2025 *value = convert_to_mode (TYPE_MODE (type), *value, 0);
2032 /* Generate all the code for a function call
2033 and return an rtx for its value.
2034 Store the value in TARGET (specified as an rtx) if convenient.
2035 If the value is stored in TARGET then TARGET is returned.
2036 If IGNORE is nonzero, then we ignore the value of the function call. */
2039 expand_call (tree exp, rtx target, int ignore)
2041 /* Nonzero if we are currently expanding a call. */
2042 static int currently_expanding_call = 0;
2044 /* List of actual parameters. */
2045 tree actparms = TREE_OPERAND (exp, 1);
2046 /* RTX for the function to be called. */
2048 /* Sequence of insns to perform a tail recursive "call". */
2049 rtx tail_recursion_insns = NULL_RTX;
2050 /* Sequence of insns to perform a normal "call". */
2051 rtx normal_call_insns = NULL_RTX;
2052 /* Sequence of insns to perform a tail recursive "call". */
2053 rtx tail_call_insns = NULL_RTX;
2054 /* Data type of the function. */
2056 tree type_arg_types;
2057 /* Declaration of the function being called,
2058 or 0 if the function is computed (not known by name). */
2060 /* The type of the function being called. */
2063 int try_tail_call = 1;
2064 int try_tail_recursion = 1;
2067 /* Register in which non-BLKmode value will be returned,
2068 or 0 if no value or if value is BLKmode. */
2070 /* Address where we should return a BLKmode value;
2071 0 if value not BLKmode. */
2072 rtx structure_value_addr = 0;
2073 /* Nonzero if that address is being passed by treating it as
2074 an extra, implicit first parameter. Otherwise,
2075 it is passed by being copied directly into struct_value_rtx. */
2076 int structure_value_addr_parm = 0;
2077 /* Size of aggregate value wanted, or zero if none wanted
2078 or if we are using the non-reentrant PCC calling convention
2079 or expecting the value in registers. */
2080 HOST_WIDE_INT struct_value_size = 0;
2081 /* Nonzero if called function returns an aggregate in memory PCC style,
2082 by returning the address of where to find it. */
2083 int pcc_struct_value = 0;
2084 rtx struct_value = 0;
2086 /* Number of actual parameters in this call, including struct value addr. */
2088 /* Number of named args. Args after this are anonymous ones
2089 and they must all go on the stack. */
2092 /* Vector of information about each argument.
2093 Arguments are numbered in the order they will be pushed,
2094 not the order they are written. */
2095 struct arg_data *args;
2097 /* Total size in bytes of all the stack-parms scanned so far. */
2098 struct args_size args_size;
2099 struct args_size adjusted_args_size;
2100 /* Size of arguments before any adjustments (such as rounding). */
2101 int unadjusted_args_size;
2102 /* Data on reg parms scanned so far. */
2103 CUMULATIVE_ARGS args_so_far;
2104 /* Nonzero if a reg parm has been scanned. */
2106 /* Nonzero if this is an indirect function call. */
2108 /* Nonzero if we must avoid push-insns in the args for this call.
2109 If stack space is allocated for register parameters, but not by the
2110 caller, then it is preallocated in the fixed part of the stack frame.
2111 So the entire argument block must then be preallocated (i.e., we
2112 ignore PUSH_ROUNDING in that case). */
2114 int must_preallocate = !PUSH_ARGS;
2116 /* Size of the stack reserved for parameter registers. */
2117 int reg_parm_stack_space = 0;
2119 /* Address of space preallocated for stack parms
2120 (on machines that lack push insns), or 0 if space not preallocated. */
2123 /* Mask of ECF_ flags. */
2125 /* Nonzero if this is a call to an inline function. */
2126 int is_integrable = 0;
2127 #ifdef REG_PARM_STACK_SPACE
2128 /* Define the boundary of the register parm stack space that needs to be
2130 int low_to_save, high_to_save;
2131 rtx save_area = 0; /* Place that it is saved */
2134 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2135 rtx temp_target = 0;
2136 char *initial_stack_usage_map = stack_usage_map;
2138 int old_stack_allocated;
2140 /* State variables to track stack modifications. */
2141 rtx old_stack_level = 0;
2142 int old_stack_arg_under_construction = 0;
2143 int old_pending_adj = 0;
2144 int old_inhibit_defer_pop = inhibit_defer_pop;
2146 /* Some stack pointer alterations we make are performed via
2147 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
2148 which we then also need to save/restore along the way. */
2149 int old_stack_pointer_delta = 0;
2152 tree p = TREE_OPERAND (exp, 0);
2153 tree addr = TREE_OPERAND (exp, 0);
2155 /* The alignment of the stack, in bits. */
2156 HOST_WIDE_INT preferred_stack_boundary;
2157 /* The alignment of the stack, in bytes. */
2158 HOST_WIDE_INT preferred_unit_stack_boundary;
2160 /* See if this is "nothrow" function call. */
2161 if (TREE_NOTHROW (exp))
2162 flags |= ECF_NOTHROW;
2164 /* See if we can find a DECL-node for the actual function.
2165 As a result, decide whether this is a call to an integrable function. */
2167 fndecl = get_callee_fndecl (exp);
2170 fntype = TREE_TYPE (fndecl);
2172 && fndecl != current_function_decl
2173 && DECL_INLINE (fndecl)
2174 && DECL_STRUCT_FUNCTION (fndecl)
2175 && DECL_STRUCT_FUNCTION (fndecl)->inlinable)
2177 else if (! TREE_ADDRESSABLE (fndecl))
2179 /* In case this function later becomes inlinable,
2180 record that there was already a non-inline call to it.
2182 Use abstraction instead of setting TREE_ADDRESSABLE
2184 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2187 warning ("%Jcan't inline call to '%F'", fndecl, fndecl);
2188 warning ("called from here");
2190 lang_hooks.mark_addressable (fndecl);
2194 && lookup_attribute ("warn_unused_result",
2195 TYPE_ATTRIBUTES (TREE_TYPE (fndecl))))
2196 warning ("ignoring return value of `%D', "
2197 "declared with attribute warn_unused_result", fndecl);
2199 flags |= flags_from_decl_or_type (fndecl);
2202 /* If we don't have specific function to call, see if we have a
2203 attributes set in the type. */
2206 fntype = TREE_TYPE (TREE_TYPE (p));
2208 && lookup_attribute ("warn_unused_result", TYPE_ATTRIBUTES (fntype)))
2209 warning ("ignoring return value of function "
2210 "declared with attribute warn_unused_result");
2211 flags |= flags_from_decl_or_type (fntype);
2214 struct_value = targetm.calls.struct_value_rtx (fntype, 0);
2216 /* Warn if this value is an aggregate type,
2217 regardless of which calling convention we are using for it. */
2218 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2219 warning ("function call has aggregate value");
2221 /* If the result of a pure or const function call is ignored (or void),
2222 and none of its arguments are volatile, we can avoid expanding the
2223 call and just evaluate the arguments for side-effects. */
2224 if ((flags & (ECF_CONST | ECF_PURE))
2225 && (ignore || target == const0_rtx
2226 || TYPE_MODE (TREE_TYPE (exp)) == VOIDmode))
2228 bool volatilep = false;
2231 for (arg = actparms; arg; arg = TREE_CHAIN (arg))
2232 if (TREE_THIS_VOLATILE (TREE_VALUE (arg)))
2240 for (arg = actparms; arg; arg = TREE_CHAIN (arg))
2241 expand_expr (TREE_VALUE (arg), const0_rtx,
2242 VOIDmode, EXPAND_NORMAL);
2247 #ifdef REG_PARM_STACK_SPACE
2248 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2251 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2252 if (reg_parm_stack_space > 0 && PUSH_ARGS)
2253 must_preallocate = 1;
2256 /* Set up a place to return a structure. */
2258 /* Cater to broken compilers. */
2259 if (aggregate_value_p (exp, fndecl))
2261 /* This call returns a big structure. */
2262 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
2264 #ifdef PCC_STATIC_STRUCT_RETURN
2266 pcc_struct_value = 1;
2267 /* Easier than making that case work right. */
2270 /* In case this is a static function, note that it has been
2272 if (! TREE_ADDRESSABLE (fndecl))
2273 lang_hooks.mark_addressable (fndecl);
2277 #else /* not PCC_STATIC_STRUCT_RETURN */
2279 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2281 if (CALL_EXPR_HAS_RETURN_SLOT_ADDR (exp))
2283 /* The structure value address arg is already in actparms.
2284 Pull it out. It might be nice to just leave it there, but
2285 we need to set structure_value_addr. */
2286 tree return_arg = TREE_VALUE (actparms);
2287 actparms = TREE_CHAIN (actparms);
2288 structure_value_addr = expand_expr (return_arg, NULL_RTX,
2289 VOIDmode, EXPAND_NORMAL);
2291 else if (target && GET_CODE (target) == MEM)
2292 structure_value_addr = XEXP (target, 0);
2295 /* For variable-sized objects, we must be called with a target
2296 specified. If we were to allocate space on the stack here,
2297 we would have no way of knowing when to free it. */
2298 rtx d = assign_temp (TREE_TYPE (exp), 1, 1, 1);
2300 mark_temp_addr_taken (d);
2301 structure_value_addr = XEXP (d, 0);
2305 #endif /* not PCC_STATIC_STRUCT_RETURN */
2308 /* If called function is inline, try to integrate it. */
2312 rtx temp = try_to_integrate (fndecl, actparms, target,
2313 ignore, TREE_TYPE (exp),
2314 structure_value_addr);
2315 if (temp != (rtx) (size_t) - 1)
2319 /* Figure out the amount to which the stack should be aligned. */
2320 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2323 struct cgraph_rtl_info *i = cgraph_rtl_info (fndecl);
2324 if (i && i->preferred_incoming_stack_boundary)
2325 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
2328 /* Operand 0 is a pointer-to-function; get the type of the function. */
2329 funtype = TREE_TYPE (addr);
2330 if (! POINTER_TYPE_P (funtype))
2332 funtype = TREE_TYPE (funtype);
2334 /* Munge the tree to split complex arguments into their imaginary
2336 if (targetm.calls.split_complex_arg)
2338 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
2339 actparms = split_complex_values (actparms);
2342 type_arg_types = TYPE_ARG_TYPES (funtype);
2344 /* See if this is a call to a function that can return more than once
2345 or a call to longjmp or malloc. */
2346 flags |= special_function_p (fndecl, flags);
2348 if (flags & ECF_MAY_BE_ALLOCA)
2349 current_function_calls_alloca = 1;
2351 /* If struct_value_rtx is 0, it means pass the address
2352 as if it were an extra parameter. */
2353 if (structure_value_addr && struct_value == 0)
2355 /* If structure_value_addr is a REG other than
2356 virtual_outgoing_args_rtx, we can use always use it. If it
2357 is not a REG, we must always copy it into a register.
2358 If it is virtual_outgoing_args_rtx, we must copy it to another
2359 register in some cases. */
2360 rtx temp = (GET_CODE (structure_value_addr) != REG
2361 || (ACCUMULATE_OUTGOING_ARGS
2362 && stack_arg_under_construction
2363 && structure_value_addr == virtual_outgoing_args_rtx)
2364 ? copy_addr_to_reg (convert_memory_address
2365 (Pmode, structure_value_addr))
2366 : structure_value_addr);
2369 = tree_cons (error_mark_node,
2370 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2373 structure_value_addr_parm = 1;
2376 /* Count the arguments and set NUM_ACTUALS. */
2377 for (p = actparms, num_actuals = 0; p; p = TREE_CHAIN (p))
2380 /* Compute number of named args.
2381 Normally, don't include the last named arg if anonymous args follow.
2382 We do include the last named arg if
2383 targetm.calls.strict_argument_naming() returns nonzero.
2384 (If no anonymous args follow, the result of list_length is actually
2385 one too large. This is harmless.)
2387 If targetm.calls.pretend_outgoing_varargs_named() returns
2388 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2389 this machine will be able to place unnamed args that were passed
2390 in registers into the stack. So treat all args as named. This
2391 allows the insns emitting for a specific argument list to be
2392 independent of the function declaration.
2394 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2395 we do not have any reliable way to pass unnamed args in
2396 registers, so we must force them into memory. */
2398 if ((targetm.calls.strict_argument_naming (&args_so_far)
2399 || ! targetm.calls.pretend_outgoing_varargs_named (&args_so_far))
2400 && type_arg_types != 0)
2402 = (list_length (type_arg_types)
2403 /* Don't include the last named arg. */
2404 - (targetm.calls.strict_argument_naming (&args_so_far) ? 0 : 1)
2405 /* Count the struct value address, if it is passed as a parm. */
2406 + structure_value_addr_parm);
2408 /* If we know nothing, treat all args as named. */
2409 n_named_args = num_actuals;
2411 /* Start updating where the next arg would go.
2413 On some machines (such as the PA) indirect calls have a different
2414 calling convention than normal calls. The fourth argument in
2415 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2417 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, fndecl, n_named_args);
2419 /* Make a vector to hold all the information about each arg. */
2420 args = alloca (num_actuals * sizeof (struct arg_data));
2421 memset (args, 0, num_actuals * sizeof (struct arg_data));
2423 /* Build up entries in the ARGS array, compute the size of the
2424 arguments into ARGS_SIZE, etc. */
2425 initialize_argument_information (num_actuals, args, &args_size,
2426 n_named_args, actparms, fndecl,
2427 &args_so_far, reg_parm_stack_space,
2428 &old_stack_level, &old_pending_adj,
2429 &must_preallocate, &flags,
2430 CALL_FROM_THUNK_P (exp));
2434 /* If this function requires a variable-sized argument list, don't
2435 try to make a cse'able block for this call. We may be able to
2436 do this eventually, but it is too complicated to keep track of
2437 what insns go in the cse'able block and which don't. */
2439 flags &= ~ECF_LIBCALL_BLOCK;
2440 must_preallocate = 1;
2443 /* Now make final decision about preallocating stack space. */
2444 must_preallocate = finalize_must_preallocate (must_preallocate,
2448 /* If the structure value address will reference the stack pointer, we
2449 must stabilize it. We don't need to do this if we know that we are
2450 not going to adjust the stack pointer in processing this call. */
2452 if (structure_value_addr
2453 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2454 || reg_mentioned_p (virtual_outgoing_args_rtx,
2455 structure_value_addr))
2457 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2458 structure_value_addr = copy_to_reg (structure_value_addr);
2460 /* Tail calls can make things harder to debug, and we're traditionally
2461 pushed these optimizations into -O2. Don't try if we're already
2462 expanding a call, as that means we're an argument. Don't try if
2463 there's cleanups, as we know there's code to follow the call.
2465 If rtx_equal_function_value_matters is false, that means we've
2466 finished with regular parsing. Which means that some of the
2467 machinery we use to generate tail-calls is no longer in place.
2468 This is most often true of sjlj-exceptions, which we couldn't
2469 tail-call to anyway.
2471 If current_nesting_level () == 0, we're being called after
2472 the function body has been expanded. This can happen when
2473 setting up trampolines in expand_function_end. */
2474 if (currently_expanding_call++ != 0
2475 || !flag_optimize_sibling_calls
2476 || !rtx_equal_function_value_matters
2477 || current_nesting_level () == 0
2478 || any_pending_cleanups ()
2480 try_tail_call = try_tail_recursion = 0;
2482 /* Tail recursion fails, when we are not dealing with recursive calls. */
2483 if (!try_tail_recursion
2484 || TREE_CODE (addr) != ADDR_EXPR
2485 || TREE_OPERAND (addr, 0) != current_function_decl)
2486 try_tail_recursion = 0;
2488 /* Rest of purposes for tail call optimizations to fail. */
2490 #ifdef HAVE_sibcall_epilogue
2491 !HAVE_sibcall_epilogue
2496 /* Doing sibling call optimization needs some work, since
2497 structure_value_addr can be allocated on the stack.
2498 It does not seem worth the effort since few optimizable
2499 sibling calls will return a structure. */
2500 || structure_value_addr != NULL_RTX
2501 /* Check whether the target is able to optimize the call
2503 || !targetm.function_ok_for_sibcall (fndecl, exp)
2504 /* Functions that do not return exactly once may not be sibcall
2506 || (flags & (ECF_RETURNS_TWICE | ECF_LONGJMP | ECF_NORETURN))
2507 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr)))
2508 /* If the called function is nested in the current one, it might access
2509 some of the caller's arguments, but could clobber them beforehand if
2510 the argument areas are shared. */
2511 || (fndecl && decl_function_context (fndecl) == current_function_decl)
2512 /* If this function requires more stack slots than the current
2513 function, we cannot change it into a sibling call. */
2514 || args_size.constant > current_function_args_size
2515 /* If the callee pops its own arguments, then it must pop exactly
2516 the same number of arguments as the current function. */
2517 || (RETURN_POPS_ARGS (fndecl, funtype, args_size.constant)
2518 != RETURN_POPS_ARGS (current_function_decl,
2519 TREE_TYPE (current_function_decl),
2520 current_function_args_size))
2521 || !lang_hooks.decls.ok_for_sibcall (fndecl))
2524 if (try_tail_call || try_tail_recursion)
2527 actparms = NULL_TREE;
2528 /* Ok, we're going to give the tail call the old college try.
2529 This means we're going to evaluate the function arguments
2530 up to three times. There are two degrees of badness we can
2531 encounter, those that can be unsaved and those that can't.
2532 (See unsafe_for_reeval commentary for details.)
2534 Generate a new argument list. Pass safe arguments through
2535 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2536 For hard badness, evaluate them now and put their resulting
2537 rtx in a temporary VAR_DECL.
2539 initialize_argument_information has ordered the array for the
2540 order to be pushed, and we must remember this when reconstructing
2541 the original argument order. */
2543 if (PUSH_ARGS_REVERSED)
2552 i = num_actuals - 1;
2556 for (; i != end; i += inc)
2558 args[i].tree_value = fix_unsafe_tree (args[i].tree_value);
2559 /* We need to build actparms for optimize_tail_recursion. We can
2560 safely trash away TREE_PURPOSE, since it is unused by this
2562 if (try_tail_recursion)
2563 actparms = tree_cons (NULL_TREE, args[i].tree_value, actparms);
2565 /* Do the same for the function address if it is an expression. */
2567 addr = fix_unsafe_tree (addr);
2568 /* Expanding one of those dangerous arguments could have added
2569 cleanups, but otherwise give it a whirl. */
2570 if (any_pending_cleanups ())
2571 try_tail_call = try_tail_recursion = 0;
2574 /* Generate a tail recursion sequence when calling ourselves. */
2576 if (try_tail_recursion)
2578 /* We want to emit any pending stack adjustments before the tail
2579 recursion "call". That way we know any adjustment after the tail
2580 recursion call can be ignored if we indeed use the tail recursion
2582 int save_pending_stack_adjust = pending_stack_adjust;
2583 int save_stack_pointer_delta = stack_pointer_delta;
2585 /* Emit any queued insns now; otherwise they would end up in
2586 only one of the alternates. */
2589 /* Use a new sequence to hold any RTL we generate. We do not even
2590 know if we will use this RTL yet. The final decision can not be
2591 made until after RTL generation for the entire function is
2594 /* If expanding any of the arguments creates cleanups, we can't
2595 do a tailcall. So, we'll need to pop the pending cleanups
2596 list. If, however, all goes well, and there are no cleanups
2597 then the call to expand_start_target_temps will have no
2599 expand_start_target_temps ();
2600 if (optimize_tail_recursion (actparms, get_last_insn ()))
2602 if (any_pending_cleanups ())
2603 try_tail_call = try_tail_recursion = 0;
2605 tail_recursion_insns = get_insns ();
2607 expand_end_target_temps ();
2610 /* Restore the original pending stack adjustment for the sibling and
2611 normal call cases below. */
2612 pending_stack_adjust = save_pending_stack_adjust;
2613 stack_pointer_delta = save_stack_pointer_delta;
2616 /* Ensure current function's preferred stack boundary is at least
2617 what we need. We don't have to increase alignment for recursive
2619 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2620 && fndecl != current_function_decl)
2621 cfun->preferred_stack_boundary = preferred_stack_boundary;
2622 if (fndecl == current_function_decl)
2623 cfun->recursive_call_emit = true;
2625 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2627 function_call_count++;
2629 /* We want to make two insn chains; one for a sibling call, the other
2630 for a normal call. We will select one of the two chains after
2631 initial RTL generation is complete. */
2632 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
2634 int sibcall_failure = 0;
2635 /* We want to emit any pending stack adjustments before the tail
2636 recursion "call". That way we know any adjustment after the tail
2637 recursion call can be ignored if we indeed use the tail recursion
2639 int save_pending_stack_adjust = 0;
2640 int save_stack_pointer_delta = 0;
2642 rtx before_call, next_arg_reg;
2646 /* Emit any queued insns now; otherwise they would end up in
2647 only one of the alternates. */
2650 /* State variables we need to save and restore between
2652 save_pending_stack_adjust = pending_stack_adjust;
2653 save_stack_pointer_delta = stack_pointer_delta;
2656 flags &= ~ECF_SIBCALL;
2658 flags |= ECF_SIBCALL;
2660 /* Other state variables that we must reinitialize each time
2661 through the loop (that are not initialized by the loop itself). */
2665 /* Start a new sequence for the normal call case.
2667 From this point on, if the sibling call fails, we want to set
2668 sibcall_failure instead of continuing the loop. */
2673 /* We know at this point that there are not currently any
2674 pending cleanups. If, however, in the process of evaluating
2675 the arguments we were to create some, we'll need to be
2676 able to get rid of them. */
2677 expand_start_target_temps ();
2680 /* Don't let pending stack adjusts add up to too much.
2681 Also, do all pending adjustments now if there is any chance
2682 this might be a call to alloca or if we are expanding a sibling
2683 call sequence or if we are calling a function that is to return
2684 with stack pointer depressed. */
2685 if (pending_stack_adjust >= 32
2686 || (pending_stack_adjust > 0
2687 && (flags & (ECF_MAY_BE_ALLOCA | ECF_SP_DEPRESSED)))
2689 do_pending_stack_adjust ();
2691 /* When calling a const function, we must pop the stack args right away,
2692 so that the pop is deleted or moved with the call. */
2693 if (pass && (flags & ECF_LIBCALL_BLOCK))
2696 /* Precompute any arguments as needed. */
2698 precompute_arguments (flags, num_actuals, args);
2700 /* Now we are about to start emitting insns that can be deleted
2701 if a libcall is deleted. */
2702 if (pass && (flags & (ECF_LIBCALL_BLOCK | ECF_MALLOC)))
2705 adjusted_args_size = args_size;
2706 /* Compute the actual size of the argument block required. The variable
2707 and constant sizes must be combined, the size may have to be rounded,
2708 and there may be a minimum required size. When generating a sibcall
2709 pattern, do not round up, since we'll be re-using whatever space our
2711 unadjusted_args_size
2712 = compute_argument_block_size (reg_parm_stack_space,
2713 &adjusted_args_size,
2715 : preferred_stack_boundary));
2717 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2719 /* The argument block when performing a sibling call is the
2720 incoming argument block. */
2723 argblock = virtual_incoming_args_rtx;
2725 #ifdef STACK_GROWS_DOWNWARD
2726 = plus_constant (argblock, current_function_pretend_args_size);
2728 = plus_constant (argblock, -current_function_pretend_args_size);
2730 stored_args_map = sbitmap_alloc (args_size.constant);
2731 sbitmap_zero (stored_args_map);
2734 /* If we have no actual push instructions, or shouldn't use them,
2735 make space for all args right now. */
2736 else if (adjusted_args_size.var != 0)
2738 if (old_stack_level == 0)
2740 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2741 old_stack_pointer_delta = stack_pointer_delta;
2742 old_pending_adj = pending_stack_adjust;
2743 pending_stack_adjust = 0;
2744 /* stack_arg_under_construction says whether a stack arg is
2745 being constructed at the old stack level. Pushing the stack
2746 gets a clean outgoing argument block. */
2747 old_stack_arg_under_construction = stack_arg_under_construction;
2748 stack_arg_under_construction = 0;
2750 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2754 /* Note that we must go through the motions of allocating an argument
2755 block even if the size is zero because we may be storing args
2756 in the area reserved for register arguments, which may be part of
2759 int needed = adjusted_args_size.constant;
2761 /* Store the maximum argument space used. It will be pushed by
2762 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2765 if (needed > current_function_outgoing_args_size)
2766 current_function_outgoing_args_size = needed;
2768 if (must_preallocate)
2770 if (ACCUMULATE_OUTGOING_ARGS)
2772 /* Since the stack pointer will never be pushed, it is
2773 possible for the evaluation of a parm to clobber
2774 something we have already written to the stack.
2775 Since most function calls on RISC machines do not use
2776 the stack, this is uncommon, but must work correctly.
2778 Therefore, we save any area of the stack that was already
2779 written and that we are using. Here we set up to do this
2780 by making a new stack usage map from the old one. The
2781 actual save will be done by store_one_arg.
2783 Another approach might be to try to reorder the argument
2784 evaluations to avoid this conflicting stack usage. */
2786 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2787 /* Since we will be writing into the entire argument area,
2788 the map must be allocated for its entire size, not just
2789 the part that is the responsibility of the caller. */
2790 needed += reg_parm_stack_space;
2793 #ifdef ARGS_GROW_DOWNWARD
2794 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2797 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2800 stack_usage_map = alloca (highest_outgoing_arg_in_use);
2802 if (initial_highest_arg_in_use)
2803 memcpy (stack_usage_map, initial_stack_usage_map,
2804 initial_highest_arg_in_use);
2806 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2807 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2808 (highest_outgoing_arg_in_use
2809 - initial_highest_arg_in_use));
2812 /* The address of the outgoing argument list must not be
2813 copied to a register here, because argblock would be left
2814 pointing to the wrong place after the call to
2815 allocate_dynamic_stack_space below. */
2817 argblock = virtual_outgoing_args_rtx;
2821 if (inhibit_defer_pop == 0)
2823 /* Try to reuse some or all of the pending_stack_adjust
2824 to get this space. */
2826 = (combine_pending_stack_adjustment_and_call
2827 (unadjusted_args_size,
2828 &adjusted_args_size,
2829 preferred_unit_stack_boundary));
2831 /* combine_pending_stack_adjustment_and_call computes
2832 an adjustment before the arguments are allocated.
2833 Account for them and see whether or not the stack
2834 needs to go up or down. */
2835 needed = unadjusted_args_size - needed;
2839 /* We're releasing stack space. */
2840 /* ??? We can avoid any adjustment at all if we're
2841 already aligned. FIXME. */
2842 pending_stack_adjust = -needed;
2843 do_pending_stack_adjust ();
2847 /* We need to allocate space. We'll do that in
2848 push_block below. */
2849 pending_stack_adjust = 0;
2852 /* Special case this because overhead of `push_block' in
2853 this case is non-trivial. */
2855 argblock = virtual_outgoing_args_rtx;
2858 argblock = push_block (GEN_INT (needed), 0, 0);
2859 #ifdef ARGS_GROW_DOWNWARD
2860 argblock = plus_constant (argblock, needed);
2864 /* We only really need to call `copy_to_reg' in the case
2865 where push insns are going to be used to pass ARGBLOCK
2866 to a function call in ARGS. In that case, the stack
2867 pointer changes value from the allocation point to the
2868 call point, and hence the value of
2869 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2870 as well always do it. */
2871 argblock = copy_to_reg (argblock);
2876 if (ACCUMULATE_OUTGOING_ARGS)
2878 /* The save/restore code in store_one_arg handles all
2879 cases except one: a constructor call (including a C
2880 function returning a BLKmode struct) to initialize
2882 if (stack_arg_under_construction)
2884 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2885 rtx push_size = GEN_INT (reg_parm_stack_space
2886 + adjusted_args_size.constant);
2888 rtx push_size = GEN_INT (adjusted_args_size.constant);
2890 if (old_stack_level == 0)
2892 emit_stack_save (SAVE_BLOCK, &old_stack_level,
2894 old_stack_pointer_delta = stack_pointer_delta;
2895 old_pending_adj = pending_stack_adjust;
2896 pending_stack_adjust = 0;
2897 /* stack_arg_under_construction says whether a stack
2898 arg is being constructed at the old stack level.
2899 Pushing the stack gets a clean outgoing argument
2901 old_stack_arg_under_construction
2902 = stack_arg_under_construction;
2903 stack_arg_under_construction = 0;
2904 /* Make a new map for the new argument list. */
2905 stack_usage_map = alloca (highest_outgoing_arg_in_use);
2906 memset (stack_usage_map, 0, highest_outgoing_arg_in_use);
2907 highest_outgoing_arg_in_use = 0;
2909 allocate_dynamic_stack_space (push_size, NULL_RTX,
2913 /* If argument evaluation might modify the stack pointer,
2914 copy the address of the argument list to a register. */
2915 for (i = 0; i < num_actuals; i++)
2916 if (args[i].pass_on_stack)
2918 argblock = copy_addr_to_reg (argblock);
2923 compute_argument_addresses (args, argblock, num_actuals);
2925 /* If we push args individually in reverse order, perform stack alignment
2926 before the first push (the last arg). */
2927 if (PUSH_ARGS_REVERSED && argblock == 0
2928 && adjusted_args_size.constant != unadjusted_args_size)
2930 /* When the stack adjustment is pending, we get better code
2931 by combining the adjustments. */
2932 if (pending_stack_adjust
2933 && ! (flags & ECF_LIBCALL_BLOCK)
2934 && ! inhibit_defer_pop)
2936 pending_stack_adjust
2937 = (combine_pending_stack_adjustment_and_call
2938 (unadjusted_args_size,
2939 &adjusted_args_size,
2940 preferred_unit_stack_boundary));
2941 do_pending_stack_adjust ();
2943 else if (argblock == 0)
2944 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2945 - unadjusted_args_size));
2947 /* Now that the stack is properly aligned, pops can't safely
2948 be deferred during the evaluation of the arguments. */
2951 funexp = rtx_for_function_call (fndecl, addr);
2953 /* Figure out the register where the value, if any, will come back. */
2955 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2956 && ! structure_value_addr)
2958 if (pcc_struct_value)
2959 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2960 fndecl, (pass == 0));
2962 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
2965 /* Precompute all register parameters. It isn't safe to compute anything
2966 once we have started filling any specific hard regs. */
2967 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2969 #ifdef REG_PARM_STACK_SPACE
2970 /* Save the fixed argument area if it's part of the caller's frame and
2971 is clobbered by argument setup for this call. */
2972 if (ACCUMULATE_OUTGOING_ARGS && pass)
2973 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2974 &low_to_save, &high_to_save);
2977 /* Now store (and compute if necessary) all non-register parms.
2978 These come before register parms, since they can require block-moves,
2979 which could clobber the registers used for register parms.
2980 Parms which have partial registers are not stored here,
2981 but we do preallocate space here if they want that. */
2983 for (i = 0; i < num_actuals; i++)
2984 if (args[i].reg == 0 || args[i].pass_on_stack)
2986 rtx before_arg = get_last_insn ();
2988 if (store_one_arg (&args[i], argblock, flags,
2989 adjusted_args_size.var != 0,
2990 reg_parm_stack_space)
2992 && check_sibcall_argument_overlap (before_arg,
2994 sibcall_failure = 1;
2996 if (flags & ECF_CONST
2998 && args[i].value == args[i].stack)
2999 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3000 gen_rtx_USE (VOIDmode,
3005 /* If we have a parm that is passed in registers but not in memory
3006 and whose alignment does not permit a direct copy into registers,
3007 make a group of pseudos that correspond to each register that we
3009 if (STRICT_ALIGNMENT)
3010 store_unaligned_arguments_into_pseudos (args, num_actuals);
3012 /* Now store any partially-in-registers parm.
3013 This is the last place a block-move can happen. */
3015 for (i = 0; i < num_actuals; i++)
3016 if (args[i].partial != 0 && ! args[i].pass_on_stack)
3018 rtx before_arg = get_last_insn ();
3020 if (store_one_arg (&args[i], argblock, flags,
3021 adjusted_args_size.var != 0,
3022 reg_parm_stack_space)
3024 && check_sibcall_argument_overlap (before_arg,
3026 sibcall_failure = 1;
3029 /* If we pushed args in forward order, perform stack alignment
3030 after pushing the last arg. */
3031 if (!PUSH_ARGS_REVERSED && argblock == 0)
3032 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3033 - unadjusted_args_size));
3035 /* If register arguments require space on the stack and stack space
3036 was not preallocated, allocate stack space here for arguments
3037 passed in registers. */
3038 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3039 if (!ACCUMULATE_OUTGOING_ARGS
3040 && must_preallocate == 0 && reg_parm_stack_space > 0)
3041 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3044 /* Pass the function the address in which to return a
3046 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3048 structure_value_addr
3049 = convert_memory_address (Pmode, structure_value_addr);
3050 emit_move_insn (struct_value,
3052 force_operand (structure_value_addr,
3055 if (GET_CODE (struct_value) == REG)
3056 use_reg (&call_fusage, struct_value);
3059 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
3060 reg_parm_seen, pass == 0);
3062 load_register_parameters (args, num_actuals, &call_fusage, flags,
3063 pass == 0, &sibcall_failure);
3065 /* Perform postincrements before actually calling the function. */
3068 /* Save a pointer to the last insn before the call, so that we can
3069 later safely search backwards to find the CALL_INSN. */
3070 before_call = get_last_insn ();
3072 /* Set up next argument register. For sibling calls on machines
3073 with register windows this should be the incoming register. */
3074 #ifdef FUNCTION_INCOMING_ARG
3076 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
3080 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
3083 /* All arguments and registers used for the call must be set up by
3086 /* Stack must be properly aligned now. */
3087 if (pass && stack_pointer_delta % preferred_unit_stack_boundary)
3090 /* Generate the actual call instruction. */
3091 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
3092 adjusted_args_size.constant, struct_value_size,
3093 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3094 flags, & args_so_far);
3096 /* If call is cse'able, make appropriate pair of reg-notes around it.
3097 Test valreg so we don't crash; may safely ignore `const'
3098 if return type is void. Disable for PARALLEL return values, because
3099 we have no way to move such values into a pseudo register. */
3100 if (pass && (flags & ECF_LIBCALL_BLOCK))
3104 bool failed = valreg == 0 || GET_CODE (valreg) == PARALLEL;
3106 insns = get_insns ();
3108 /* Expansion of block moves possibly introduced a loop that may
3109 not appear inside libcall block. */
3110 for (insn = insns; insn; insn = NEXT_INSN (insn))
3111 if (GET_CODE (insn) == JUMP_INSN)
3122 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3124 /* Mark the return value as a pointer if needed. */
3125 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3126 mark_reg_pointer (temp,
3127 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
3130 if (flag_unsafe_math_optimizations
3132 && DECL_BUILT_IN (fndecl)
3133 && (DECL_FUNCTION_CODE (fndecl) == BUILT_IN_SQRT
3134 || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_SQRTF
3135 || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_SQRTL))
3136 note = gen_rtx_fmt_e (SQRT,
3138 args[0].initial_value);
3141 /* Construct an "equal form" for the value which
3142 mentions all the arguments in order as well as
3143 the function name. */
3144 for (i = 0; i < num_actuals; i++)
3145 note = gen_rtx_EXPR_LIST (VOIDmode,
3146 args[i].initial_value, note);
3147 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
3149 if (flags & ECF_PURE)
3150 note = gen_rtx_EXPR_LIST (VOIDmode,
3151 gen_rtx_USE (VOIDmode,
3152 gen_rtx_MEM (BLKmode,
3153 gen_rtx_SCRATCH (VOIDmode))),
3156 emit_libcall_block (insns, temp, valreg, note);
3161 else if (pass && (flags & ECF_MALLOC))
3163 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3166 /* The return value from a malloc-like function is a pointer. */
3167 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3168 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3170 emit_move_insn (temp, valreg);
3172 /* The return value from a malloc-like function can not alias
3174 last = get_last_insn ();
3176 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
3178 /* Write out the sequence. */
3179 insns = get_insns ();
3185 /* For calls to `setjmp', etc., inform flow.c it should complain
3186 if nonvolatile values are live. For functions that cannot return,
3187 inform flow that control does not fall through. */
3189 if ((flags & (ECF_NORETURN | ECF_LONGJMP)) || pass == 0)
3191 /* The barrier must be emitted
3192 immediately after the CALL_INSN. Some ports emit more
3193 than just a CALL_INSN above, so we must search for it here. */
3195 rtx last = get_last_insn ();
3196 while (GET_CODE (last) != CALL_INSN)
3198 last = PREV_INSN (last);
3199 /* There was no CALL_INSN? */
3200 if (last == before_call)
3204 emit_barrier_after (last);
3206 /* Stack adjustments after a noreturn call are dead code.
3207 However when NO_DEFER_POP is in effect, we must preserve
3208 stack_pointer_delta. */
3209 if (inhibit_defer_pop == 0)
3211 stack_pointer_delta = old_stack_allocated;
3212 pending_stack_adjust = 0;
3216 if (flags & ECF_LONGJMP)
3217 current_function_calls_longjmp = 1;
3219 /* If value type not void, return an rtx for the value. */
3221 /* If there are cleanups to be called, don't use a hard reg as target.
3222 We need to double check this and see if it matters anymore. */
3223 if (any_pending_cleanups ())
3225 if (target && REG_P (target)
3226 && REGNO (target) < FIRST_PSEUDO_REGISTER)
3228 sibcall_failure = 1;
3231 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
3233 target = const0_rtx;
3234 else if (structure_value_addr)
3236 if (target == 0 || GET_CODE (target) != MEM)
3239 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3240 memory_address (TYPE_MODE (TREE_TYPE (exp)),
3241 structure_value_addr));
3242 set_mem_attributes (target, exp, 1);
3245 else if (pcc_struct_value)
3247 /* This is the special C++ case where we need to
3248 know what the true target was. We take care to
3249 never use this value more than once in one expression. */
3250 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3251 copy_to_reg (valreg));
3252 set_mem_attributes (target, exp, 1);
3254 /* Handle calls that return values in multiple non-contiguous locations.
3255 The Irix 6 ABI has examples of this. */
3256 else if (GET_CODE (valreg) == PARALLEL)
3258 /* Second condition is added because "target" is freed at the
3259 the end of "pass0" for -O2 when call is made to
3260 expand_end_target_temps (). Its "in_use" flag has been set
3261 to false, so allocate a new temp. */
3262 if (target == 0 || (pass == 1 && target == temp_target))
3264 /* This will only be assigned once, so it can be readonly. */
3265 tree nt = build_qualified_type (TREE_TYPE (exp),
3266 (TYPE_QUALS (TREE_TYPE (exp))
3267 | TYPE_QUAL_CONST));
3269 target = assign_temp (nt, 0, 1, 1);
3270 temp_target = target;
3271 preserve_temp_slots (target);
3274 if (! rtx_equal_p (target, valreg))
3275 emit_group_store (target, valreg, TREE_TYPE (exp),
3276 int_size_in_bytes (TREE_TYPE (exp)));
3278 /* We can not support sibling calls for this case. */
3279 sibcall_failure = 1;
3282 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
3283 && GET_MODE (target) == GET_MODE (valreg))
3285 /* TARGET and VALREG cannot be equal at this point because the
3286 latter would not have REG_FUNCTION_VALUE_P true, while the
3287 former would if it were referring to the same register.
3289 If they refer to the same register, this move will be a no-op,
3290 except when function inlining is being done. */
3291 emit_move_insn (target, valreg);
3293 /* If we are setting a MEM, this code must be executed. Since it is
3294 emitted after the call insn, sibcall optimization cannot be
3295 performed in that case. */
3296 if (GET_CODE (target) == MEM)
3297 sibcall_failure = 1;
3299 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3301 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3303 /* We can not support sibling calls for this case. */
3304 sibcall_failure = 1;
3308 if (shift_returned_value (TREE_TYPE (exp), &valreg))
3309 sibcall_failure = 1;
3311 target = copy_to_reg (valreg);
3314 if (targetm.calls.promote_function_return(funtype))
3316 /* If we promoted this return value, make the proper SUBREG. TARGET
3317 might be const0_rtx here, so be careful. */
3318 if (GET_CODE (target) == REG
3319 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3320 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3322 tree type = TREE_TYPE (exp);
3323 int unsignedp = TYPE_UNSIGNED (type);
3326 /* If we don't promote as expected, something is wrong. */
3327 if (GET_MODE (target)
3328 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
3331 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3332 && GET_MODE_SIZE (GET_MODE (target))
3333 > GET_MODE_SIZE (TYPE_MODE (type)))
3335 offset = GET_MODE_SIZE (GET_MODE (target))
3336 - GET_MODE_SIZE (TYPE_MODE (type));
3337 if (! BYTES_BIG_ENDIAN)
3338 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3339 else if (! WORDS_BIG_ENDIAN)
3340 offset %= UNITS_PER_WORD;
3342 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3343 SUBREG_PROMOTED_VAR_P (target) = 1;
3344 SUBREG_PROMOTED_UNSIGNED_SET (target, unsignedp);
3348 /* If size of args is variable or this was a constructor call for a stack
3349 argument, restore saved stack-pointer value. */
3351 if (old_stack_level && ! (flags & ECF_SP_DEPRESSED))
3353 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3354 stack_pointer_delta = old_stack_pointer_delta;
3355 pending_stack_adjust = old_pending_adj;
3356 stack_arg_under_construction = old_stack_arg_under_construction;
3357 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3358 stack_usage_map = initial_stack_usage_map;
3359 sibcall_failure = 1;
3361 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3363 #ifdef REG_PARM_STACK_SPACE
3365 restore_fixed_argument_area (save_area, argblock,
3366 high_to_save, low_to_save);
3369 /* If we saved any argument areas, restore them. */
3370 for (i = 0; i < num_actuals; i++)
3371 if (args[i].save_area)
3373 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3375 = gen_rtx_MEM (save_mode,
3376 memory_address (save_mode,
3377 XEXP (args[i].stack_slot, 0)));
3379 if (save_mode != BLKmode)
3380 emit_move_insn (stack_area, args[i].save_area);
3382 emit_block_move (stack_area, args[i].save_area,
3383 GEN_INT (args[i].locate.size.constant),
3384 BLOCK_OP_CALL_PARM);
3387 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3388 stack_usage_map = initial_stack_usage_map;
3391 /* If this was alloca, record the new stack level for nonlocal gotos.
3392 Check for the handler slots since we might not have a save area
3393 for non-local gotos. */
3395 if ((flags & ECF_MAY_BE_ALLOCA) && nonlocal_goto_handler_slots != 0)
3396 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3398 /* Free up storage we no longer need. */
3399 for (i = 0; i < num_actuals; ++i)
3400 if (args[i].aligned_regs)
3401 free (args[i].aligned_regs);
3405 /* Undo the fake expand_start_target_temps we did earlier. If
3406 there had been any cleanups created, we've already set
3408 expand_end_target_temps ();
3411 /* If this function is returning into a memory location marked as
3412 readonly, it means it is initializing that location. We normally treat
3413 functions as not clobbering such locations, so we need to specify that
3414 this one does. We do this by adding the appropriate CLOBBER to the
3415 CALL_INSN function usage list. This cannot be done by emitting a
3416 standalone CLOBBER after the call because the latter would be ignored
3417 by at least the delay slot scheduling pass. We do this now instead of
3418 adding to call_fusage before the call to emit_call_1 because TARGET
3419 may be modified in the meantime. */
3420 if (structure_value_addr != 0 && target != 0
3421 && GET_CODE (target) == MEM && RTX_UNCHANGING_P (target))
3422 add_function_usage_to
3424 gen_rtx_EXPR_LIST (VOIDmode, gen_rtx_CLOBBER (VOIDmode, target),
3427 insns = get_insns ();
3432 tail_call_insns = insns;
3434 /* Restore the pending stack adjustment now that we have
3435 finished generating the sibling call sequence. */
3437 pending_stack_adjust = save_pending_stack_adjust;
3438 stack_pointer_delta = save_stack_pointer_delta;
3440 /* Prepare arg structure for next iteration. */
3441 for (i = 0; i < num_actuals; i++)
3444 args[i].aligned_regs = 0;
3448 sbitmap_free (stored_args_map);
3452 normal_call_insns = insns;
3454 /* Verify that we've deallocated all the stack we used. */
3455 if (! (flags & (ECF_NORETURN | ECF_LONGJMP))
3456 && old_stack_allocated != stack_pointer_delta
3457 - pending_stack_adjust)
3461 /* If something prevents making this a sibling call,
3462 zero out the sequence. */
3463 if (sibcall_failure)
3464 tail_call_insns = NULL_RTX;
3467 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3468 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3469 can happen if the arguments to this function call an inline
3470 function who's expansion contains another CALL_PLACEHOLDER.
3472 If there are any C_Ps in any of these sequences, replace them
3473 with their normal call. */
3475 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3476 if (GET_CODE (insn) == CALL_INSN
3477 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3478 replace_call_placeholder (insn, sibcall_use_normal);
3480 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
3481 if (GET_CODE (insn) == CALL_INSN
3482 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3483 replace_call_placeholder (insn, sibcall_use_normal);
3485 for (insn = tail_recursion_insns; insn; insn = NEXT_INSN (insn))
3486 if (GET_CODE (insn) == CALL_INSN
3487 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3488 replace_call_placeholder (insn, sibcall_use_normal);
3490 /* If this was a potential tail recursion site, then emit a
3491 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3492 One of them will be selected later. */
3493 if (tail_recursion_insns || tail_call_insns)
3495 /* The tail recursion label must be kept around. We could expose
3496 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3497 and makes determining true tail recursion sites difficult.
3499 So we set LABEL_PRESERVE_P here, then clear it when we select
3500 one of the call sequences after rtl generation is complete. */
3501 if (tail_recursion_insns)
3502 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3503 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3505 tail_recursion_insns,
3506 tail_recursion_label));
3509 emit_insn (normal_call_insns);
3511 currently_expanding_call--;
3513 /* If this function returns with the stack pointer depressed, ensure
3514 this block saves and restores the stack pointer, show it was
3515 changed, and adjust for any outgoing arg space. */
3516 if (flags & ECF_SP_DEPRESSED)
3518 clear_pending_stack_adjust ();
3519 emit_insn (gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx));
3520 emit_move_insn (virtual_stack_dynamic_rtx, stack_pointer_rtx);
3521 save_stack_pointer ();
3527 /* Traverse an argument list in VALUES and expand all complex
3528 arguments into their components. */
3530 split_complex_values (tree values)
3534 /* Before allocating memory, check for the common case of no complex. */
3535 for (p = values; p; p = TREE_CHAIN (p))
3537 tree type = TREE_TYPE (TREE_VALUE (p));
3538 if (type && TREE_CODE (type) == COMPLEX_TYPE
3539 && targetm.calls.split_complex_arg (type))
3545 values = copy_list (values);
3547 for (p = values; p; p = TREE_CHAIN (p))
3549 tree complex_value = TREE_VALUE (p);
3552 complex_type = TREE_TYPE (complex_value);
3556 if (TREE_CODE (complex_type) == COMPLEX_TYPE
3557 && targetm.calls.split_complex_arg (complex_type))
3560 tree real, imag, next;
3562 subtype = TREE_TYPE (complex_type);
3563 complex_value = save_expr (complex_value);
3564 real = build1 (REALPART_EXPR, subtype, complex_value);
3565 imag = build1 (IMAGPART_EXPR, subtype, complex_value);
3567 TREE_VALUE (p) = real;
3568 next = TREE_CHAIN (p);
3569 imag = build_tree_list (NULL_TREE, imag);
3570 TREE_CHAIN (p) = imag;
3571 TREE_CHAIN (imag) = next;
3573 /* Skip the newly created node. */
3581 /* Traverse a list of TYPES and expand all complex types into their
3584 split_complex_types (tree types)
3588 /* Before allocating memory, check for the common case of no complex. */
3589 for (p = types; p; p = TREE_CHAIN (p))
3591 tree type = TREE_VALUE (p);
3592 if (TREE_CODE (type) == COMPLEX_TYPE
3593 && targetm.calls.split_complex_arg (type))
3599 types = copy_list (types);
3601 for (p = types; p; p = TREE_CHAIN (p))
3603 tree complex_type = TREE_VALUE (p);
3605 if (TREE_CODE (complex_type) == COMPLEX_TYPE
3606 && targetm.calls.split_complex_arg (complex_type))
3610 /* Rewrite complex type with component type. */
3611 TREE_VALUE (p) = TREE_TYPE (complex_type);
3612 next = TREE_CHAIN (p);
3614 /* Add another component type for the imaginary part. */
3615 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
3616 TREE_CHAIN (p) = imag;
3617 TREE_CHAIN (imag) = next;
3619 /* Skip the newly created node. */
3627 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3628 The RETVAL parameter specifies whether return value needs to be saved, other
3629 parameters are documented in the emit_library_call function below. */
3632 emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
3633 enum libcall_type fn_type,
3634 enum machine_mode outmode, int nargs, va_list p)
3636 /* Total size in bytes of all the stack-parms scanned so far. */
3637 struct args_size args_size;
3638 /* Size of arguments before any adjustments (such as rounding). */
3639 struct args_size original_args_size;
3645 CUMULATIVE_ARGS args_so_far;
3649 enum machine_mode mode;
3652 struct locate_and_pad_arg_data locate;
3656 int old_inhibit_defer_pop = inhibit_defer_pop;
3657 rtx call_fusage = 0;
3660 int pcc_struct_value = 0;
3661 int struct_value_size = 0;
3663 int reg_parm_stack_space = 0;
3666 tree tfom; /* type_for_mode (outmode, 0) */
3668 #ifdef REG_PARM_STACK_SPACE
3669 /* Define the boundary of the register parm stack space that needs to be
3671 int low_to_save, high_to_save;
3672 rtx save_area = 0; /* Place that it is saved. */
3675 /* Size of the stack reserved for parameter registers. */
3676 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3677 char *initial_stack_usage_map = stack_usage_map;
3679 rtx struct_value = targetm.calls.struct_value_rtx (0, 0);
3681 #ifdef REG_PARM_STACK_SPACE
3682 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3685 /* By default, library functions can not throw. */
3686 flags = ECF_NOTHROW;
3698 case LCT_CONST_MAKE_BLOCK:
3699 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
3701 case LCT_PURE_MAKE_BLOCK:
3702 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
3705 flags |= ECF_NORETURN;
3708 flags = ECF_NORETURN;
3710 case LCT_ALWAYS_RETURN:
3711 flags = ECF_ALWAYS_RETURN;
3713 case LCT_RETURNS_TWICE:
3714 flags = ECF_RETURNS_TWICE;
3719 /* Ensure current function's preferred stack boundary is at least
3721 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3722 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3724 /* If this kind of value comes back in memory,
3725 decide where in memory it should come back. */
3726 if (outmode != VOIDmode)
3728 tfom = lang_hooks.types.type_for_mode (outmode, 0);
3729 if (aggregate_value_p (tfom, 0))
3731 #ifdef PCC_STATIC_STRUCT_RETURN
3733 = hard_function_value (build_pointer_type (tfom), 0, 0);
3734 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3735 pcc_struct_value = 1;
3737 value = gen_reg_rtx (outmode);
3738 #else /* not PCC_STATIC_STRUCT_RETURN */
3739 struct_value_size = GET_MODE_SIZE (outmode);
3740 if (value != 0 && GET_CODE (value) == MEM)
3743 mem_value = assign_temp (tfom, 0, 1, 1);
3745 /* This call returns a big structure. */
3746 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3750 tfom = void_type_node;
3752 /* ??? Unfinished: must pass the memory address as an argument. */
3754 /* Copy all the libcall-arguments out of the varargs data
3755 and into a vector ARGVEC.
3757 Compute how to pass each argument. We only support a very small subset
3758 of the full argument passing conventions to limit complexity here since
3759 library functions shouldn't have many args. */
3761 argvec = alloca ((nargs + 1) * sizeof (struct arg));
3762 memset (argvec, 0, (nargs + 1) * sizeof (struct arg));
3764 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3765 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far, outmode, fun);
3767 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0, nargs);
3770 args_size.constant = 0;
3775 /* Now we are about to start emitting insns that can be deleted
3776 if a libcall is deleted. */
3777 if (flags & ECF_LIBCALL_BLOCK)
3782 /* If there's a structure value address to be passed,
3783 either pass it in the special place, or pass it as an extra argument. */
3784 if (mem_value && struct_value == 0 && ! pcc_struct_value)
3786 rtx addr = XEXP (mem_value, 0);
3789 /* Make sure it is a reasonable operand for a move or push insn. */
3790 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3791 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3792 addr = force_operand (addr, NULL_RTX);
3794 argvec[count].value = addr;
3795 argvec[count].mode = Pmode;
3796 argvec[count].partial = 0;
3798 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3799 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3800 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3804 locate_and_pad_parm (Pmode, NULL_TREE,
3805 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3808 argvec[count].reg != 0,
3810 0, NULL_TREE, &args_size, &argvec[count].locate);
3812 if (argvec[count].reg == 0 || argvec[count].partial != 0
3813 || reg_parm_stack_space > 0)
3814 args_size.constant += argvec[count].locate.size.constant;
3816 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3821 for (; count < nargs; count++)
3823 rtx val = va_arg (p, rtx);
3824 enum machine_mode mode = va_arg (p, enum machine_mode);
3826 /* We cannot convert the arg value to the mode the library wants here;
3827 must do it earlier where we know the signedness of the arg. */
3829 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3832 /* There's no need to call protect_from_queue, because
3833 either emit_move_insn or emit_push_insn will do that. */
3835 /* Make sure it is a reasonable operand for a move or push insn. */
3836 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3837 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3838 val = force_operand (val, NULL_RTX);
3840 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3841 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3845 #ifdef FUNCTION_ARG_CALLEE_COPIES
3846 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far, mode,
3851 /* loop.c won't look at CALL_INSN_FUNCTION_USAGE of const/pure
3852 functions, so we have to pretend this isn't such a function. */
3853 if (flags & ECF_LIBCALL_BLOCK)
3855 rtx insns = get_insns ();
3859 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3861 /* If this was a CONST function, it is now PURE since
3862 it now reads memory. */
3863 if (flags & ECF_CONST)
3865 flags &= ~ECF_CONST;
3869 if (GET_MODE (val) == MEM && ! must_copy)
3873 slot = assign_temp (lang_hooks.types.type_for_mode (mode, 0),
3875 emit_move_insn (slot, val);
3879 tree type = lang_hooks.types.type_for_mode (mode, 0);
3882 = gen_rtx_MEM (mode,
3883 expand_expr (build1 (ADDR_EXPR,
3884 build_pointer_type (type),
3885 make_tree (type, val)),
3886 NULL_RTX, VOIDmode, 0));
3889 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3890 gen_rtx_USE (VOIDmode, slot),
3893 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3894 gen_rtx_CLOBBER (VOIDmode,
3899 val = force_operand (XEXP (slot, 0), NULL_RTX);
3903 argvec[count].value = val;
3904 argvec[count].mode = mode;
3906 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3908 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3909 argvec[count].partial
3910 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3912 argvec[count].partial = 0;
3915 locate_and_pad_parm (mode, NULL_TREE,
3916 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3919 argvec[count].reg != 0,
3921 argvec[count].partial,
3922 NULL_TREE, &args_size, &argvec[count].locate);
3924 if (argvec[count].locate.size.var)
3927 if (argvec[count].reg == 0 || argvec[count].partial != 0
3928 || reg_parm_stack_space > 0)
3929 args_size.constant += argvec[count].locate.size.constant;
3931 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3934 /* If this machine requires an external definition for library
3935 functions, write one out. */
3936 assemble_external_libcall (fun);
3938 original_args_size = args_size;
3939 args_size.constant = (((args_size.constant
3940 + stack_pointer_delta
3944 - stack_pointer_delta);
3946 args_size.constant = MAX (args_size.constant,
3947 reg_parm_stack_space);
3949 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3950 args_size.constant -= reg_parm_stack_space;
3953 if (args_size.constant > current_function_outgoing_args_size)
3954 current_function_outgoing_args_size = args_size.constant;
3956 if (ACCUMULATE_OUTGOING_ARGS)
3958 /* Since the stack pointer will never be pushed, it is possible for
3959 the evaluation of a parm to clobber something we have already
3960 written to the stack. Since most function calls on RISC machines
3961 do not use the stack, this is uncommon, but must work correctly.
3963 Therefore, we save any area of the stack that was already written
3964 and that we are using. Here we set up to do this by making a new
3965 stack usage map from the old one.
3967 Another approach might be to try to reorder the argument
3968 evaluations to avoid this conflicting stack usage. */
3970 needed = args_size.constant;
3972 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3973 /* Since we will be writing into the entire argument area, the
3974 map must be allocated for its entire size, not just the part that
3975 is the responsibility of the caller. */
3976 needed += reg_parm_stack_space;
3979 #ifdef ARGS_GROW_DOWNWARD
3980 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3983 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3986 stack_usage_map = alloca (highest_outgoing_arg_in_use);
3988 if (initial_highest_arg_in_use)
3989 memcpy (stack_usage_map, initial_stack_usage_map,
3990 initial_highest_arg_in_use);
3992 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3993 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3994 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3997 /* We must be careful to use virtual regs before they're instantiated,
3998 and real regs afterwards. Loop optimization, for example, can create
3999 new libcalls after we've instantiated the virtual regs, and if we
4000 use virtuals anyway, they won't match the rtl patterns. */
4002 if (virtuals_instantiated)
4003 argblock = plus_constant (stack_pointer_rtx, STACK_POINTER_OFFSET);
4005 argblock = virtual_outgoing_args_rtx;
4010 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
4013 /* If we push args individually in reverse order, perform stack alignment
4014 before the first push (the last arg). */
4015 if (argblock == 0 && PUSH_ARGS_REVERSED)
4016 anti_adjust_stack (GEN_INT (args_size.constant
4017 - original_args_size.constant));
4019 if (PUSH_ARGS_REVERSED)
4030 #ifdef REG_PARM_STACK_SPACE
4031 if (ACCUMULATE_OUTGOING_ARGS)
4033 /* The argument list is the property of the called routine and it
4034 may clobber it. If the fixed area has been used for previous
4035 parameters, we must save and restore it. */
4036 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
4037 &low_to_save, &high_to_save);
4041 /* Push the args that need to be pushed. */
4043 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4044 are to be pushed. */
4045 for (count = 0; count < nargs; count++, argnum += inc)
4047 enum machine_mode mode = argvec[argnum].mode;
4048 rtx val = argvec[argnum].value;
4049 rtx reg = argvec[argnum].reg;
4050 int partial = argvec[argnum].partial;
4051 int lower_bound = 0, upper_bound = 0, i;
4053 if (! (reg != 0 && partial == 0))
4055 if (ACCUMULATE_OUTGOING_ARGS)
4057 /* If this is being stored into a pre-allocated, fixed-size,
4058 stack area, save any previous data at that location. */
4060 #ifdef ARGS_GROW_DOWNWARD
4061 /* stack_slot is negative, but we want to index stack_usage_map
4062 with positive values. */
4063 upper_bound = -argvec[argnum].locate.offset.constant + 1;
4064 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
4066 lower_bound = argvec[argnum].locate.offset.constant;
4067 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
4071 /* Don't worry about things in the fixed argument area;
4072 it has already been saved. */
4073 if (i < reg_parm_stack_space)
4074 i = reg_parm_stack_space;
4075 while (i < upper_bound && stack_usage_map[i] == 0)
4078 if (i < upper_bound)
4080 /* We need to make a save area. */
4082 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
4083 enum machine_mode save_mode
4084 = mode_for_size (size, MODE_INT, 1);
4086 = plus_constant (argblock,
4087 argvec[argnum].locate.offset.constant);
4089 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
4091 if (save_mode == BLKmode)
4093 argvec[argnum].save_area
4094 = assign_stack_temp (BLKmode,
4095 argvec[argnum].locate.size.constant,
4098 emit_block_move (validize_mem (argvec[argnum].save_area),
4100 GEN_INT (argvec[argnum].locate.size.constant),
4101 BLOCK_OP_CALL_PARM);
4105 argvec[argnum].save_area = gen_reg_rtx (save_mode);
4107 emit_move_insn (argvec[argnum].save_area, stack_area);
4112 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, PARM_BOUNDARY,
4113 partial, reg, 0, argblock,
4114 GEN_INT (argvec[argnum].locate.offset.constant),
4115 reg_parm_stack_space,
4116 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad));
4118 /* Now mark the segment we just used. */
4119 if (ACCUMULATE_OUTGOING_ARGS)
4120 for (i = lower_bound; i < upper_bound; i++)
4121 stack_usage_map[i] = 1;
4127 /* If we pushed args in forward order, perform stack alignment
4128 after pushing the last arg. */
4129 if (argblock == 0 && !PUSH_ARGS_REVERSED)
4130 anti_adjust_stack (GEN_INT (args_size.constant
4131 - original_args_size.constant));
4133 if (PUSH_ARGS_REVERSED)
4138 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0, 0);
4140 /* Now load any reg parms into their regs. */
4142 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4143 are to be pushed. */
4144 for (count = 0; count < nargs; count++, argnum += inc)
4146 rtx val = argvec[argnum].value;
4147 rtx reg = argvec[argnum].reg;
4148 int partial = argvec[argnum].partial;
4150 /* Handle calls that pass values in multiple non-contiguous
4151 locations. The PA64 has examples of this for library calls. */
4152 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4153 emit_group_load (reg, val, NULL_TREE, GET_MODE_SIZE (GET_MODE (val)));
4154 else if (reg != 0 && partial == 0)
4155 emit_move_insn (reg, val);
4160 /* Any regs containing parms remain in use through the call. */
4161 for (count = 0; count < nargs; count++)
4163 rtx reg = argvec[count].reg;
4164 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4165 use_group_regs (&call_fusage, reg);
4167 use_reg (&call_fusage, reg);
4170 /* Pass the function the address in which to return a structure value. */
4171 if (mem_value != 0 && struct_value != 0 && ! pcc_struct_value)
4173 emit_move_insn (struct_value,
4175 force_operand (XEXP (mem_value, 0),
4177 if (GET_CODE (struct_value) == REG)
4178 use_reg (&call_fusage, struct_value);
4181 /* Don't allow popping to be deferred, since then
4182 cse'ing of library calls could delete a call and leave the pop. */
4184 valreg = (mem_value == 0 && outmode != VOIDmode
4185 ? hard_libcall_value (outmode) : NULL_RTX);
4187 /* Stack must be properly aligned now. */
4188 if (stack_pointer_delta & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1))
4191 before_call = get_last_insn ();
4193 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4194 will set inhibit_defer_pop to that value. */
4195 /* The return type is needed to decide how many bytes the function pops.
4196 Signedness plays no role in that, so for simplicity, we pretend it's
4197 always signed. We also assume that the list of arguments passed has
4198 no impact, so we pretend it is unknown. */
4201 get_identifier (XSTR (orgfun, 0)),
4202 build_function_type (tfom, NULL_TREE),
4203 original_args_size.constant, args_size.constant,
4205 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
4207 old_inhibit_defer_pop + 1, call_fusage, flags, & args_so_far);
4209 /* For calls to `setjmp', etc., inform flow.c it should complain
4210 if nonvolatile values are live. For functions that cannot return,
4211 inform flow that control does not fall through. */
4213 if (flags & (ECF_NORETURN | ECF_LONGJMP))
4215 /* The barrier note must be emitted
4216 immediately after the CALL_INSN. Some ports emit more than
4217 just a CALL_INSN above, so we must search for it here. */
4219 rtx last = get_last_insn ();
4220 while (GET_CODE (last) != CALL_INSN)
4222 last = PREV_INSN (last);
4223 /* There was no CALL_INSN? */
4224 if (last == before_call)
4228 emit_barrier_after (last);
4231 /* Now restore inhibit_defer_pop to its actual original value. */
4234 /* If call is cse'able, make appropriate pair of reg-notes around it.
4235 Test valreg so we don't crash; may safely ignore `const'
4236 if return type is void. Disable for PARALLEL return values, because
4237 we have no way to move such values into a pseudo register. */
4238 if (flags & ECF_LIBCALL_BLOCK)
4244 insns = get_insns ();
4254 if (GET_CODE (valreg) == PARALLEL)
4256 temp = gen_reg_rtx (outmode);
4257 emit_group_store (temp, valreg, NULL_TREE,
4258 GET_MODE_SIZE (outmode));
4262 temp = gen_reg_rtx (GET_MODE (valreg));
4264 /* Construct an "equal form" for the value which mentions all the
4265 arguments in order as well as the function name. */
4266 for (i = 0; i < nargs; i++)
4267 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
4268 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
4270 insns = get_insns ();
4273 if (flags & ECF_PURE)
4274 note = gen_rtx_EXPR_LIST (VOIDmode,
4275 gen_rtx_USE (VOIDmode,
4276 gen_rtx_MEM (BLKmode,
4277 gen_rtx_SCRATCH (VOIDmode))),
4280 emit_libcall_block (insns, temp, valreg, note);
4287 /* Copy the value to the right place. */
4288 if (outmode != VOIDmode && retval)
4294 if (value != mem_value)
4295 emit_move_insn (value, mem_value);
4297 else if (GET_CODE (valreg) == PARALLEL)
4300 value = gen_reg_rtx (outmode);
4301 emit_group_store (value, valreg, NULL_TREE, GET_MODE_SIZE (outmode));
4303 else if (value != 0)
4304 emit_move_insn (value, valreg);
4309 if (ACCUMULATE_OUTGOING_ARGS)
4311 #ifdef REG_PARM_STACK_SPACE
4313 restore_fixed_argument_area (save_area, argblock,
4314 high_to_save, low_to_save);
4317 /* If we saved any argument areas, restore them. */
4318 for (count = 0; count < nargs; count++)
4319 if (argvec[count].save_area)
4321 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4322 rtx adr = plus_constant (argblock,
4323 argvec[count].locate.offset.constant);
4324 rtx stack_area = gen_rtx_MEM (save_mode,
4325 memory_address (save_mode, adr));
4327 if (save_mode == BLKmode)
4328 emit_block_move (stack_area,
4329 validize_mem (argvec[count].save_area),
4330 GEN_INT (argvec[count].locate.size.constant),
4331 BLOCK_OP_CALL_PARM);
4333 emit_move_insn (stack_area, argvec[count].save_area);
4336 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4337 stack_usage_map = initial_stack_usage_map;
4344 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4345 (emitting the queue unless NO_QUEUE is nonzero),
4346 for a value of mode OUTMODE,
4347 with NARGS different arguments, passed as alternating rtx values
4348 and machine_modes to convert them to.
4349 The rtx values should have been passed through protect_from_queue already.
4351 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4352 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4353 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4354 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4355 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4356 or other LCT_ value for other types of library calls. */
4359 emit_library_call (rtx orgfun, enum libcall_type fn_type,
4360 enum machine_mode outmode, int nargs, ...)
4364 va_start (p, nargs);
4365 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4369 /* Like emit_library_call except that an extra argument, VALUE,
4370 comes second and says where to store the result.
4371 (If VALUE is zero, this function chooses a convenient way
4372 to return the value.
4374 This function returns an rtx for where the value is to be found.
4375 If VALUE is nonzero, VALUE is returned. */
4378 emit_library_call_value (rtx orgfun, rtx value,
4379 enum libcall_type fn_type,
4380 enum machine_mode outmode, int nargs, ...)
4385 va_start (p, nargs);
4386 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4393 /* Store a single argument for a function call
4394 into the register or memory area where it must be passed.
4395 *ARG describes the argument value and where to pass it.
4397 ARGBLOCK is the address of the stack-block for all the arguments,
4398 or 0 on a machine where arguments are pushed individually.
4400 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4401 so must be careful about how the stack is used.
4403 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4404 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4405 that we need not worry about saving and restoring the stack.
4407 FNDECL is the declaration of the function we are calling.
4409 Return nonzero if this arg should cause sibcall failure,
4413 store_one_arg (struct arg_data *arg, rtx argblock, int flags,
4414 int variable_size ATTRIBUTE_UNUSED, int reg_parm_stack_space)
4416 tree pval = arg->tree_value;
4420 int i, lower_bound = 0, upper_bound = 0;
4421 int sibcall_failure = 0;
4423 if (TREE_CODE (pval) == ERROR_MARK)
4426 /* Push a new temporary level for any temporaries we make for
4430 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4432 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4433 save any previous data at that location. */
4434 if (argblock && ! variable_size && arg->stack)
4436 #ifdef ARGS_GROW_DOWNWARD
4437 /* stack_slot is negative, but we want to index stack_usage_map
4438 with positive values. */
4439 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4440 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4444 lower_bound = upper_bound - arg->locate.size.constant;
4446 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4447 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4451 upper_bound = lower_bound + arg->locate.size.constant;
4455 /* Don't worry about things in the fixed argument area;
4456 it has already been saved. */
4457 if (i < reg_parm_stack_space)
4458 i = reg_parm_stack_space;
4459 while (i < upper_bound && stack_usage_map[i] == 0)
4462 if (i < upper_bound)
4464 /* We need to make a save area. */
4465 unsigned int size = arg->locate.size.constant * BITS_PER_UNIT;
4466 enum machine_mode save_mode = mode_for_size (size, MODE_INT, 1);
4467 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
4468 rtx stack_area = gen_rtx_MEM (save_mode, adr);
4470 if (save_mode == BLKmode)
4472 tree ot = TREE_TYPE (arg->tree_value);
4473 tree nt = build_qualified_type (ot, (TYPE_QUALS (ot)
4474 | TYPE_QUAL_CONST));
4476 arg->save_area = assign_temp (nt, 0, 1, 1);
4477 preserve_temp_slots (arg->save_area);
4478 emit_block_move (validize_mem (arg->save_area), stack_area,
4479 expr_size (arg->tree_value),
4480 BLOCK_OP_CALL_PARM);
4484 arg->save_area = gen_reg_rtx (save_mode);
4485 emit_move_insn (arg->save_area, stack_area);
4491 /* If this isn't going to be placed on both the stack and in registers,
4492 set up the register and number of words. */
4493 if (! arg->pass_on_stack)
4495 if (flags & ECF_SIBCALL)
4496 reg = arg->tail_call_reg;
4499 partial = arg->partial;
4502 if (reg != 0 && partial == 0)
4503 /* Being passed entirely in a register. We shouldn't be called in
4507 /* If this arg needs special alignment, don't load the registers
4509 if (arg->n_aligned_regs != 0)
4512 /* If this is being passed partially in a register, we can't evaluate
4513 it directly into its stack slot. Otherwise, we can. */
4514 if (arg->value == 0)
4516 /* stack_arg_under_construction is nonzero if a function argument is
4517 being evaluated directly into the outgoing argument list and
4518 expand_call must take special action to preserve the argument list
4519 if it is called recursively.
4521 For scalar function arguments stack_usage_map is sufficient to
4522 determine which stack slots must be saved and restored. Scalar
4523 arguments in general have pass_on_stack == 0.
4525 If this argument is initialized by a function which takes the
4526 address of the argument (a C++ constructor or a C function
4527 returning a BLKmode structure), then stack_usage_map is
4528 insufficient and expand_call must push the stack around the
4529 function call. Such arguments have pass_on_stack == 1.
4531 Note that it is always safe to set stack_arg_under_construction,
4532 but this generates suboptimal code if set when not needed. */
4534 if (arg->pass_on_stack)
4535 stack_arg_under_construction++;
4537 arg->value = expand_expr (pval,
4539 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4540 ? NULL_RTX : arg->stack,
4541 VOIDmode, EXPAND_STACK_PARM);
4543 /* If we are promoting object (or for any other reason) the mode
4544 doesn't agree, convert the mode. */
4546 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4547 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4548 arg->value, arg->unsignedp);
4550 if (arg->pass_on_stack)
4551 stack_arg_under_construction--;
4554 /* Don't allow anything left on stack from computation
4555 of argument to alloca. */
4556 if (flags & ECF_MAY_BE_ALLOCA)
4557 do_pending_stack_adjust ();
4559 if (arg->value == arg->stack)
4560 /* If the value is already in the stack slot, we are done. */
4562 else if (arg->mode != BLKmode)
4566 /* Argument is a scalar, not entirely passed in registers.
4567 (If part is passed in registers, arg->partial says how much
4568 and emit_push_insn will take care of putting it there.)
4570 Push it, and if its size is less than the
4571 amount of space allocated to it,
4572 also bump stack pointer by the additional space.
4573 Note that in C the default argument promotions
4574 will prevent such mismatches. */
4576 size = GET_MODE_SIZE (arg->mode);
4577 /* Compute how much space the push instruction will push.
4578 On many machines, pushing a byte will advance the stack
4579 pointer by a halfword. */
4580 #ifdef PUSH_ROUNDING
4581 size = PUSH_ROUNDING (size);
4585 /* Compute how much space the argument should get:
4586 round up to a multiple of the alignment for arguments. */
4587 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4588 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4589 / (PARM_BOUNDARY / BITS_PER_UNIT))
4590 * (PARM_BOUNDARY / BITS_PER_UNIT));
4592 /* This isn't already where we want it on the stack, so put it there.
4593 This can either be done with push or copy insns. */
4594 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
4595 PARM_BOUNDARY, partial, reg, used - size, argblock,
4596 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4597 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4599 /* Unless this is a partially-in-register argument, the argument is now
4602 arg->value = arg->stack;
4606 /* BLKmode, at least partly to be pushed. */
4608 unsigned int parm_align;
4612 /* Pushing a nonscalar.
4613 If part is passed in registers, PARTIAL says how much
4614 and emit_push_insn will take care of putting it there. */
4616 /* Round its size up to a multiple
4617 of the allocation unit for arguments. */
4619 if (arg->locate.size.var != 0)
4622 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
4626 /* PUSH_ROUNDING has no effect on us, because
4627 emit_push_insn for BLKmode is careful to avoid it. */
4628 if (reg && GET_CODE (reg) == PARALLEL)
4630 /* Use the size of the elt to compute excess. */
4631 rtx elt = XEXP (XVECEXP (reg, 0, 0), 0);
4632 excess = (arg->locate.size.constant
4633 - int_size_in_bytes (TREE_TYPE (pval))
4634 + partial * GET_MODE_SIZE (GET_MODE (elt)));
4637 excess = (arg->locate.size.constant
4638 - int_size_in_bytes (TREE_TYPE (pval))
4639 + partial * UNITS_PER_WORD);
4640 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
4641 NULL_RTX, TYPE_MODE (sizetype), 0);
4644 /* Some types will require stricter alignment, which will be
4645 provided for elsewhere in argument layout. */
4646 parm_align = MAX (PARM_BOUNDARY, TYPE_ALIGN (TREE_TYPE (pval)));
4648 /* When an argument is padded down, the block is aligned to
4649 PARM_BOUNDARY, but the actual argument isn't. */
4650 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4652 if (arg->locate.size.var)
4653 parm_align = BITS_PER_UNIT;
4656 unsigned int excess_align = (excess & -excess) * BITS_PER_UNIT;
4657 parm_align = MIN (parm_align, excess_align);
4661 if ((flags & ECF_SIBCALL) && GET_CODE (arg->value) == MEM)
4663 /* emit_push_insn might not work properly if arg->value and
4664 argblock + arg->locate.offset areas overlap. */
4668 if (XEXP (x, 0) == current_function_internal_arg_pointer
4669 || (GET_CODE (XEXP (x, 0)) == PLUS
4670 && XEXP (XEXP (x, 0), 0) ==
4671 current_function_internal_arg_pointer
4672 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT))
4674 if (XEXP (x, 0) != current_function_internal_arg_pointer)
4675 i = INTVAL (XEXP (XEXP (x, 0), 1));
4677 /* expand_call should ensure this. */
4678 if (arg->locate.offset.var || GET_CODE (size_rtx) != CONST_INT)
4681 if (arg->locate.offset.constant > i)
4683 if (arg->locate.offset.constant < i + INTVAL (size_rtx))
4684 sibcall_failure = 1;
4686 else if (arg->locate.offset.constant < i)
4688 if (i < arg->locate.offset.constant + INTVAL (size_rtx))
4689 sibcall_failure = 1;
4694 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4695 parm_align, partial, reg, excess, argblock,
4696 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4697 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4699 /* Unless this is a partially-in-register argument, the argument is now
4702 ??? Unlike the case above, in which we want the actual
4703 address of the data, so that we can load it directly into a
4704 register, here we want the address of the stack slot, so that
4705 it's properly aligned for word-by-word copying or something
4706 like that. It's not clear that this is always correct. */
4708 arg->value = arg->stack_slot;
4711 /* Mark all slots this store used. */
4712 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
4713 && argblock && ! variable_size && arg->stack)
4714 for (i = lower_bound; i < upper_bound; i++)
4715 stack_usage_map[i] = 1;
4717 /* Once we have pushed something, pops can't safely
4718 be deferred during the rest of the arguments. */
4721 /* ANSI doesn't require a sequence point here,
4722 but PCC has one, so this will avoid some problems. */
4725 /* Free any temporary slots made in processing this argument. Show
4726 that we might have taken the address of something and pushed that
4728 preserve_temp_slots (NULL_RTX);
4732 return sibcall_failure;
4735 /* Nonzero if we do not know how to pass TYPE solely in registers.
4736 We cannot do so in the following cases:
4738 - if the type has variable size
4739 - if the type is marked as addressable (it is required to be constructed
4741 - if the padding and mode of the type is such that a copy into a register
4742 would put it into the wrong part of the register.
4744 Which padding can't be supported depends on the byte endianness.
4746 A value in a register is implicitly padded at the most significant end.
4747 On a big-endian machine, that is the lower end in memory.
4748 So a value padded in memory at the upper end can't go in a register.
4749 For a little-endian machine, the reverse is true. */
4752 default_must_pass_in_stack (enum machine_mode mode, tree type)
4757 /* If the type has variable size... */
4758 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4761 /* If the type is marked as addressable (it is required
4762 to be constructed into the stack)... */
4763 if (TREE_ADDRESSABLE (type))
4766 /* If the padding and mode of the type is such that a copy into
4767 a register would put it into the wrong part of the register. */
4769 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
4770 && (FUNCTION_ARG_PADDING (mode, type)
4771 == (BYTES_BIG_ENDIAN ? upward : downward)))