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, 2005, 2006, 2007
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
24 #include "coretypes.h"
39 #include "langhooks.h"
45 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
46 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
48 /* Data structure and subroutines used within expand_call. */
52 /* Tree node for this argument. */
54 /* Mode for value; TYPE_MODE unless promoted. */
55 enum machine_mode mode;
56 /* Current RTL value for argument, or 0 if it isn't precomputed. */
58 /* Initially-compute RTL value for argument; only for const functions. */
60 /* Register to pass this argument in, 0 if passed on stack, or an
61 PARALLEL if the arg is to be copied into multiple non-contiguous
64 /* Register to pass this argument in when generating tail call sequence.
65 This is not the same register as for normal calls on machines with
68 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
69 form for emit_group_move. */
71 /* If REG was promoted from the actual mode of the argument expression,
72 indicates whether the promotion is sign- or zero-extended. */
74 /* Number of bytes to put in registers. 0 means put the whole arg
75 in registers. Also 0 if not passed in registers. */
77 /* Nonzero if argument must be passed on stack.
78 Note that some arguments may be passed on the stack
79 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
80 pass_on_stack identifies arguments that *cannot* go in registers. */
82 /* Some fields packaged up for locate_and_pad_parm. */
83 struct locate_and_pad_arg_data locate;
84 /* Location on the stack at which parameter should be stored. The store
85 has already been done if STACK == VALUE. */
87 /* Location on the stack of the start of this argument slot. This can
88 differ from STACK if this arg pads downward. This location is known
89 to be aligned to FUNCTION_ARG_BOUNDARY. */
91 /* Place that this stack area has been saved, if needed. */
93 /* If an argument's alignment does not permit direct copying into registers,
94 copy in smaller-sized pieces into pseudos. These are stored in a
95 block pointed to by this field. The next field says how many
96 word-sized pseudos we made. */
101 /* A vector of one char per byte of stack space. A byte if nonzero if
102 the corresponding stack location has been used.
103 This vector is used to prevent a function call within an argument from
104 clobbering any stack already set up. */
105 static char *stack_usage_map;
107 /* Size of STACK_USAGE_MAP. */
108 static int highest_outgoing_arg_in_use;
110 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
111 stack location's tail call argument has been already stored into the stack.
112 This bitmap is used to prevent sibling call optimization if function tries
113 to use parent's incoming argument slots when they have been already
114 overwritten with tail call arguments. */
115 static sbitmap stored_args_map;
117 /* stack_arg_under_construction is nonzero when an argument may be
118 initialized with a constructor call (including a C function that
119 returns a BLKmode struct) and expand_call must take special action
120 to make sure the object being constructed does not overlap the
121 argument list for the constructor call. */
122 static int stack_arg_under_construction;
124 static void emit_call_1 (rtx, tree, tree, tree, HOST_WIDE_INT, HOST_WIDE_INT,
125 HOST_WIDE_INT, rtx, rtx, int, rtx, int,
127 static void precompute_register_parameters (int, struct arg_data *, int *);
128 static int store_one_arg (struct arg_data *, rtx, int, int, int);
129 static void store_unaligned_arguments_into_pseudos (struct arg_data *, int);
130 static int finalize_must_preallocate (int, int, struct arg_data *,
132 static void precompute_arguments (int, int, struct arg_data *);
133 static int compute_argument_block_size (int, struct args_size *, int);
134 static void initialize_argument_information (int, struct arg_data *,
135 struct args_size *, int,
137 tree, CUMULATIVE_ARGS *, int,
138 rtx *, int *, int *, int *,
140 static void compute_argument_addresses (struct arg_data *, rtx, int);
141 static rtx rtx_for_function_call (tree, tree);
142 static void load_register_parameters (struct arg_data *, int, rtx *, int,
144 static rtx emit_library_call_value_1 (int, rtx, rtx, enum libcall_type,
145 enum machine_mode, int, va_list);
146 static int special_function_p (const_tree, int);
147 static int check_sibcall_argument_overlap_1 (rtx);
148 static int check_sibcall_argument_overlap (rtx, struct arg_data *, int);
150 static int combine_pending_stack_adjustment_and_call (int, struct args_size *,
152 static tree split_complex_types (tree);
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 /* Force FUNEXP into a form suitable for the address of a CALL,
160 and return that as an rtx. Also load the static chain register
161 if FNDECL is a nested function.
163 CALL_FUSAGE points to a variable holding the prospective
164 CALL_INSN_FUNCTION_USAGE information. */
167 prepare_call_address (rtx funexp, rtx static_chain_value,
168 rtx *call_fusage, int reg_parm_seen, int sibcallp)
170 /* Make a valid memory address and copy constants through pseudo-regs,
171 but not for a constant address if -fno-function-cse. */
172 if (GET_CODE (funexp) != SYMBOL_REF)
173 /* If we are using registers for parameters, force the
174 function address into a register now. */
175 funexp = ((SMALL_REGISTER_CLASSES && reg_parm_seen)
176 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
177 : memory_address (FUNCTION_MODE, funexp));
180 #ifndef NO_FUNCTION_CSE
181 if (optimize && ! flag_no_function_cse)
182 funexp = force_reg (Pmode, funexp);
186 if (static_chain_value != 0)
188 static_chain_value = convert_memory_address (Pmode, static_chain_value);
189 emit_move_insn (static_chain_rtx, static_chain_value);
191 if (REG_P (static_chain_rtx))
192 use_reg (call_fusage, static_chain_rtx);
198 /* Generate instructions to call function FUNEXP,
199 and optionally pop the results.
200 The CALL_INSN is the first insn generated.
202 FNDECL is the declaration node of the function. This is given to the
203 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
205 FUNTYPE is the data type of the function. This is given to the macro
206 RETURN_POPS_ARGS to determine whether this function pops its own args.
207 We used to allow an identifier for library functions, but that doesn't
208 work when the return type is an aggregate type and the calling convention
209 says that the pointer to this aggregate is to be popped by the callee.
211 STACK_SIZE is the number of bytes of arguments on the stack,
212 ROUNDED_STACK_SIZE is that number rounded up to
213 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
214 both to put into the call insn and to generate explicit popping
217 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
218 It is zero if this call doesn't want a structure value.
220 NEXT_ARG_REG is the rtx that results from executing
221 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
222 just after all the args have had their registers assigned.
223 This could be whatever you like, but normally it is the first
224 arg-register beyond those used for args in this call,
225 or 0 if all the arg-registers are used in this call.
226 It is passed on to `gen_call' so you can put this info in the call insn.
228 VALREG is a hard register in which a value is returned,
229 or 0 if the call does not return a value.
231 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
232 the args to this call were processed.
233 We restore `inhibit_defer_pop' to that value.
235 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
236 denote registers used by the called function. */
239 emit_call_1 (rtx funexp, tree fntree, tree fndecl ATTRIBUTE_UNUSED,
240 tree funtype ATTRIBUTE_UNUSED,
241 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED,
242 HOST_WIDE_INT rounded_stack_size,
243 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED,
244 rtx next_arg_reg ATTRIBUTE_UNUSED, rtx valreg,
245 int old_inhibit_defer_pop, rtx call_fusage, int ecf_flags,
246 CUMULATIVE_ARGS *args_so_far ATTRIBUTE_UNUSED)
248 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
250 int already_popped = 0;
251 HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
252 #if defined (HAVE_call) && defined (HAVE_call_value)
253 rtx struct_value_size_rtx;
254 struct_value_size_rtx = GEN_INT (struct_value_size);
257 #ifdef CALL_POPS_ARGS
258 n_popped += CALL_POPS_ARGS (* args_so_far);
261 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
262 and we don't want to load it into a register as an optimization,
263 because prepare_call_address already did it if it should be done. */
264 if (GET_CODE (funexp) != SYMBOL_REF)
265 funexp = memory_address (FUNCTION_MODE, funexp);
267 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
268 if ((ecf_flags & ECF_SIBCALL)
269 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
270 && (n_popped > 0 || stack_size == 0))
272 rtx n_pop = GEN_INT (n_popped);
275 /* If this subroutine pops its own args, record that in the call insn
276 if possible, for the sake of frame pointer elimination. */
279 pat = GEN_SIBCALL_VALUE_POP (valreg,
280 gen_rtx_MEM (FUNCTION_MODE, funexp),
281 rounded_stack_size_rtx, next_arg_reg,
284 pat = GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
285 rounded_stack_size_rtx, next_arg_reg, n_pop);
287 emit_call_insn (pat);
293 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
294 /* If the target has "call" or "call_value" insns, then prefer them
295 if no arguments are actually popped. If the target does not have
296 "call" or "call_value" insns, then we must use the popping versions
297 even if the call has no arguments to pop. */
298 #if defined (HAVE_call) && defined (HAVE_call_value)
299 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
302 if (HAVE_call_pop && HAVE_call_value_pop)
305 rtx n_pop = GEN_INT (n_popped);
308 /* If this subroutine pops its own args, record that in the call insn
309 if possible, for the sake of frame pointer elimination. */
312 pat = GEN_CALL_VALUE_POP (valreg,
313 gen_rtx_MEM (FUNCTION_MODE, funexp),
314 rounded_stack_size_rtx, next_arg_reg, n_pop);
316 pat = GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
317 rounded_stack_size_rtx, next_arg_reg, n_pop);
319 emit_call_insn (pat);
325 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
326 if ((ecf_flags & ECF_SIBCALL)
327 && HAVE_sibcall && HAVE_sibcall_value)
330 emit_call_insn (GEN_SIBCALL_VALUE (valreg,
331 gen_rtx_MEM (FUNCTION_MODE, funexp),
332 rounded_stack_size_rtx,
333 next_arg_reg, NULL_RTX));
335 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
336 rounded_stack_size_rtx, next_arg_reg,
337 struct_value_size_rtx));
342 #if defined (HAVE_call) && defined (HAVE_call_value)
343 if (HAVE_call && HAVE_call_value)
346 emit_call_insn (GEN_CALL_VALUE (valreg,
347 gen_rtx_MEM (FUNCTION_MODE, funexp),
348 rounded_stack_size_rtx, next_arg_reg,
351 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
352 rounded_stack_size_rtx, next_arg_reg,
353 struct_value_size_rtx));
359 /* Find the call we just emitted. */
360 call_insn = last_call_insn ();
362 /* Mark memory as used for "pure" function call. */
363 if (ecf_flags & ECF_PURE)
367 gen_rtx_USE (VOIDmode,
368 gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (VOIDmode))),
371 /* Put the register usage information there. */
372 add_function_usage_to (call_insn, call_fusage);
374 /* If this is a const call, then set the insn's unchanging bit. */
375 if (ecf_flags & (ECF_CONST | ECF_PURE))
376 CONST_OR_PURE_CALL_P (call_insn) = 1;
378 /* If this call can't throw, attach a REG_EH_REGION reg note to that
380 if (ecf_flags & ECF_NOTHROW)
381 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_EH_REGION, const0_rtx,
382 REG_NOTES (call_insn));
385 int rn = lookup_stmt_eh_region (fntree);
387 /* If rn < 0, then either (1) tree-ssa not used or (2) doesn't
388 throw, which we already took care of. */
390 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_EH_REGION, GEN_INT (rn),
391 REG_NOTES (call_insn));
394 if (ecf_flags & ECF_NORETURN)
395 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_NORETURN, const0_rtx,
396 REG_NOTES (call_insn));
398 if (ecf_flags & ECF_RETURNS_TWICE)
400 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_SETJMP, const0_rtx,
401 REG_NOTES (call_insn));
402 cfun->calls_setjmp = 1;
405 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
407 /* Restore this now, so that we do defer pops for this call's args
408 if the context of the call as a whole permits. */
409 inhibit_defer_pop = old_inhibit_defer_pop;
414 CALL_INSN_FUNCTION_USAGE (call_insn)
415 = gen_rtx_EXPR_LIST (VOIDmode,
416 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
417 CALL_INSN_FUNCTION_USAGE (call_insn));
418 rounded_stack_size -= n_popped;
419 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
420 stack_pointer_delta -= n_popped;
423 if (!ACCUMULATE_OUTGOING_ARGS)
425 /* If returning from the subroutine does not automatically pop the args,
426 we need an instruction to pop them sooner or later.
427 Perhaps do it now; perhaps just record how much space to pop later.
429 If returning from the subroutine does pop the args, indicate that the
430 stack pointer will be changed. */
432 if (rounded_stack_size != 0)
434 if (ecf_flags & ECF_NORETURN)
435 /* Just pretend we did the pop. */
436 stack_pointer_delta -= rounded_stack_size;
437 else if (flag_defer_pop && inhibit_defer_pop == 0
438 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
439 pending_stack_adjust += rounded_stack_size;
441 adjust_stack (rounded_stack_size_rtx);
444 /* When we accumulate outgoing args, we must avoid any stack manipulations.
445 Restore the stack pointer to its original value now. Usually
446 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
447 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
448 popping variants of functions exist as well.
450 ??? We may optimize similar to defer_pop above, but it is
451 probably not worthwhile.
453 ??? It will be worthwhile to enable combine_stack_adjustments even for
456 anti_adjust_stack (GEN_INT (n_popped));
459 /* Determine if the function identified by NAME and FNDECL is one with
460 special properties we wish to know about.
462 For example, if the function might return more than one time (setjmp), then
463 set RETURNS_TWICE to a nonzero value.
465 Similarly set NORETURN if the function is in the longjmp family.
467 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
468 space from the stack such as alloca. */
471 special_function_p (const_tree fndecl, int flags)
473 if (fndecl && DECL_NAME (fndecl)
474 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
475 /* Exclude functions not at the file scope, or not `extern',
476 since they are not the magic functions we would otherwise
478 FIXME: this should be handled with attributes, not with this
479 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
480 because you can declare fork() inside a function if you
482 && (DECL_CONTEXT (fndecl) == NULL_TREE
483 || TREE_CODE (DECL_CONTEXT (fndecl)) == TRANSLATION_UNIT_DECL)
484 && TREE_PUBLIC (fndecl))
486 const char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
487 const char *tname = name;
489 /* We assume that alloca will always be called by name. It
490 makes no sense to pass it as a pointer-to-function to
491 anything that does not understand its behavior. */
492 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
494 && ! strcmp (name, "alloca"))
495 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
497 && ! strcmp (name, "__builtin_alloca"))))
498 flags |= ECF_MAY_BE_ALLOCA;
500 /* Disregard prefix _, __ or __x. */
503 if (name[1] == '_' && name[2] == 'x')
505 else if (name[1] == '_')
514 && (! strcmp (tname, "setjmp")
515 || ! strcmp (tname, "setjmp_syscall")))
517 && ! strcmp (tname, "sigsetjmp"))
519 && ! strcmp (tname, "savectx")))
520 flags |= ECF_RETURNS_TWICE;
523 && ! strcmp (tname, "siglongjmp"))
524 flags |= ECF_NORETURN;
526 else if ((tname[0] == 'q' && tname[1] == 's'
527 && ! strcmp (tname, "qsetjmp"))
528 || (tname[0] == 'v' && tname[1] == 'f'
529 && ! strcmp (tname, "vfork"))
530 || (tname[0] == 'g' && tname[1] == 'e'
531 && !strcmp (tname, "getcontext")))
532 flags |= ECF_RETURNS_TWICE;
534 else if (tname[0] == 'l' && tname[1] == 'o'
535 && ! strcmp (tname, "longjmp"))
536 flags |= ECF_NORETURN;
542 /* Return nonzero when FNDECL represents a call to setjmp. */
545 setjmp_call_p (const_tree fndecl)
547 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
550 /* Return true when exp contains alloca call. */
552 alloca_call_p (const_tree exp)
554 if (TREE_CODE (exp) == CALL_EXPR
555 && TREE_CODE (CALL_EXPR_FN (exp)) == ADDR_EXPR
556 && (TREE_CODE (TREE_OPERAND (CALL_EXPR_FN (exp), 0)) == FUNCTION_DECL)
557 && (special_function_p (TREE_OPERAND (CALL_EXPR_FN (exp), 0), 0)
558 & ECF_MAY_BE_ALLOCA))
563 /* Detect flags (function attributes) from the function decl or type node. */
566 flags_from_decl_or_type (const_tree exp)
569 const_tree type = exp;
573 type = TREE_TYPE (exp);
575 /* The function exp may have the `malloc' attribute. */
576 if (DECL_IS_MALLOC (exp))
579 /* The function exp may have the `returns_twice' attribute. */
580 if (DECL_IS_RETURNS_TWICE (exp))
581 flags |= ECF_RETURNS_TWICE;
583 /* The function exp may have the `pure' attribute. */
584 if (DECL_IS_PURE (exp))
587 if (DECL_IS_NOVOPS (exp))
590 if (TREE_NOTHROW (exp))
591 flags |= ECF_NOTHROW;
593 if (TREE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
596 flags = special_function_p (exp, flags);
598 else if (TYPE_P (exp) && TYPE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
601 if (TREE_THIS_VOLATILE (exp))
602 flags |= ECF_NORETURN;
607 /* Detect flags from a CALL_EXPR. */
610 call_expr_flags (const_tree t)
613 tree decl = get_callee_fndecl (t);
616 flags = flags_from_decl_or_type (decl);
619 t = TREE_TYPE (CALL_EXPR_FN (t));
620 if (t && TREE_CODE (t) == POINTER_TYPE)
621 flags = flags_from_decl_or_type (TREE_TYPE (t));
629 /* Precompute all register parameters as described by ARGS, storing values
630 into fields within the ARGS array.
632 NUM_ACTUALS indicates the total number elements in the ARGS array.
634 Set REG_PARM_SEEN if we encounter a register parameter. */
637 precompute_register_parameters (int num_actuals, struct arg_data *args,
644 for (i = 0; i < num_actuals; i++)
645 if (args[i].reg != 0 && ! args[i].pass_on_stack)
649 if (args[i].value == 0)
652 args[i].value = expand_normal (args[i].tree_value);
653 preserve_temp_slots (args[i].value);
657 /* If the value is a non-legitimate constant, force it into a
658 pseudo now. TLS symbols sometimes need a call to resolve. */
659 if (CONSTANT_P (args[i].value)
660 && !LEGITIMATE_CONSTANT_P (args[i].value))
661 args[i].value = force_reg (args[i].mode, args[i].value);
663 /* If we are to promote the function arg to a wider mode,
666 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
668 = convert_modes (args[i].mode,
669 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
670 args[i].value, args[i].unsignedp);
672 /* If we're going to have to load the value by parts, pull the
673 parts into pseudos. The part extraction process can involve
674 non-trivial computation. */
675 if (GET_CODE (args[i].reg) == PARALLEL)
677 tree type = TREE_TYPE (args[i].tree_value);
678 args[i].parallel_value
679 = emit_group_load_into_temps (args[i].reg, args[i].value,
680 type, int_size_in_bytes (type));
683 /* If the value is expensive, and we are inside an appropriately
684 short loop, put the value into a pseudo and then put the pseudo
687 For small register classes, also do this if this call uses
688 register parameters. This is to avoid reload conflicts while
689 loading the parameters registers. */
691 else if ((! (REG_P (args[i].value)
692 || (GET_CODE (args[i].value) == SUBREG
693 && REG_P (SUBREG_REG (args[i].value)))))
694 && args[i].mode != BLKmode
695 && rtx_cost (args[i].value, SET) > COSTS_N_INSNS (1)
696 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
698 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
702 #ifdef REG_PARM_STACK_SPACE
704 /* The argument list is the property of the called routine and it
705 may clobber it. If the fixed area has been used for previous
706 parameters, we must save and restore it. */
709 save_fixed_argument_area (int reg_parm_stack_space, rtx argblock, int *low_to_save, int *high_to_save)
714 /* Compute the boundary of the area that needs to be saved, if any. */
715 high = reg_parm_stack_space;
716 #ifdef ARGS_GROW_DOWNWARD
719 if (high > highest_outgoing_arg_in_use)
720 high = highest_outgoing_arg_in_use;
722 for (low = 0; low < high; low++)
723 if (stack_usage_map[low] != 0)
726 enum machine_mode save_mode;
731 while (stack_usage_map[--high] == 0)
735 *high_to_save = high;
737 num_to_save = high - low + 1;
738 save_mode = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
740 /* If we don't have the required alignment, must do this
742 if ((low & (MIN (GET_MODE_SIZE (save_mode),
743 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
746 #ifdef ARGS_GROW_DOWNWARD
751 stack_area = gen_rtx_MEM (save_mode,
752 memory_address (save_mode,
753 plus_constant (argblock,
756 set_mem_align (stack_area, PARM_BOUNDARY);
757 if (save_mode == BLKmode)
759 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
760 emit_block_move (validize_mem (save_area), stack_area,
761 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
765 save_area = gen_reg_rtx (save_mode);
766 emit_move_insn (save_area, stack_area);
776 restore_fixed_argument_area (rtx save_area, rtx argblock, int high_to_save, int low_to_save)
778 enum machine_mode save_mode = GET_MODE (save_area);
782 #ifdef ARGS_GROW_DOWNWARD
783 delta = -high_to_save;
787 stack_area = gen_rtx_MEM (save_mode,
788 memory_address (save_mode,
789 plus_constant (argblock, delta)));
790 set_mem_align (stack_area, PARM_BOUNDARY);
792 if (save_mode != BLKmode)
793 emit_move_insn (stack_area, save_area);
795 emit_block_move (stack_area, validize_mem (save_area),
796 GEN_INT (high_to_save - low_to_save + 1),
799 #endif /* REG_PARM_STACK_SPACE */
801 /* If any elements in ARGS refer to parameters that are to be passed in
802 registers, but not in memory, and whose alignment does not permit a
803 direct copy into registers. Copy the values into a group of pseudos
804 which we will later copy into the appropriate hard registers.
806 Pseudos for each unaligned argument will be stored into the array
807 args[argnum].aligned_regs. The caller is responsible for deallocating
808 the aligned_regs array if it is nonzero. */
811 store_unaligned_arguments_into_pseudos (struct arg_data *args, int num_actuals)
815 for (i = 0; i < num_actuals; i++)
816 if (args[i].reg != 0 && ! args[i].pass_on_stack
817 && args[i].mode == BLKmode
818 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
819 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
821 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
822 int endian_correction = 0;
826 gcc_assert (args[i].partial % UNITS_PER_WORD == 0);
827 args[i].n_aligned_regs = args[i].partial / UNITS_PER_WORD;
831 args[i].n_aligned_regs
832 = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
835 args[i].aligned_regs = XNEWVEC (rtx, args[i].n_aligned_regs);
837 /* Structures smaller than a word are normally aligned to the
838 least significant byte. On a BYTES_BIG_ENDIAN machine,
839 this means we must skip the empty high order bytes when
840 calculating the bit offset. */
841 if (bytes < UNITS_PER_WORD
842 #ifdef BLOCK_REG_PADDING
843 && (BLOCK_REG_PADDING (args[i].mode,
844 TREE_TYPE (args[i].tree_value), 1)
850 endian_correction = BITS_PER_WORD - bytes * BITS_PER_UNIT;
852 for (j = 0; j < args[i].n_aligned_regs; j++)
854 rtx reg = gen_reg_rtx (word_mode);
855 rtx word = operand_subword_force (args[i].value, j, BLKmode);
856 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
858 args[i].aligned_regs[j] = reg;
859 word = extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
860 word_mode, word_mode);
862 /* There is no need to restrict this code to loading items
863 in TYPE_ALIGN sized hunks. The bitfield instructions can
864 load up entire word sized registers efficiently.
866 ??? This may not be needed anymore.
867 We use to emit a clobber here but that doesn't let later
868 passes optimize the instructions we emit. By storing 0 into
869 the register later passes know the first AND to zero out the
870 bitfield being set in the register is unnecessary. The store
871 of 0 will be deleted as will at least the first AND. */
873 emit_move_insn (reg, const0_rtx);
875 bytes -= bitsize / BITS_PER_UNIT;
876 store_bit_field (reg, bitsize, endian_correction, word_mode,
882 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
885 NUM_ACTUALS is the total number of parameters.
887 N_NAMED_ARGS is the total number of named arguments.
889 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
892 FNDECL is the tree code for the target of this call (if known)
894 ARGS_SO_FAR holds state needed by the target to know where to place
897 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
898 for arguments which are passed in registers.
900 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
901 and may be modified by this routine.
903 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
904 flags which may may be modified by this routine.
906 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
907 that requires allocation of stack space.
909 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
910 the thunked-to function. */
913 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
914 struct arg_data *args,
915 struct args_size *args_size,
916 int n_named_args ATTRIBUTE_UNUSED,
917 tree exp, tree struct_value_addr_value,
919 CUMULATIVE_ARGS *args_so_far,
920 int reg_parm_stack_space,
921 rtx *old_stack_level, int *old_pending_adj,
922 int *must_preallocate, int *ecf_flags,
923 bool *may_tailcall, bool call_from_thunk_p)
925 /* 1 if scanning parms front to back, -1 if scanning back to front. */
928 /* Count arg position in order args appear. */
933 args_size->constant = 0;
936 /* In this loop, we consider args in the order they are written.
937 We fill up ARGS from the front or from the back if necessary
938 so that in any case the first arg to be pushed ends up at the front. */
940 if (PUSH_ARGS_REVERSED)
942 i = num_actuals - 1, inc = -1;
943 /* In this case, must reverse order of args
944 so that we compute and push the last arg first. */
951 /* First fill in the actual arguments in the ARGS array, splitting
952 complex arguments if necessary. */
955 call_expr_arg_iterator iter;
958 if (struct_value_addr_value)
960 args[j].tree_value = struct_value_addr_value;
963 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
965 tree argtype = TREE_TYPE (arg);
966 if (targetm.calls.split_complex_arg
968 && TREE_CODE (argtype) == COMPLEX_TYPE
969 && targetm.calls.split_complex_arg (argtype))
971 tree subtype = TREE_TYPE (argtype);
972 arg = save_expr (arg);
973 args[j].tree_value = build1 (REALPART_EXPR, subtype, arg);
975 args[j].tree_value = build1 (IMAGPART_EXPR, subtype, arg);
978 args[j].tree_value = arg;
983 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
984 for (argpos = 0; argpos < num_actuals; i += inc, argpos++)
986 tree type = TREE_TYPE (args[i].tree_value);
988 enum machine_mode mode;
990 /* Replace erroneous argument with constant zero. */
991 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
992 args[i].tree_value = integer_zero_node, type = integer_type_node;
994 /* If TYPE is a transparent union, pass things the way we would
995 pass the first field of the union. We have already verified that
996 the modes are the same. */
997 if (TREE_CODE (type) == UNION_TYPE && TYPE_TRANSPARENT_UNION (type))
998 type = TREE_TYPE (TYPE_FIELDS (type));
1000 /* Decide where to pass this arg.
1002 args[i].reg is nonzero if all or part is passed in registers.
1004 args[i].partial is nonzero if part but not all is passed in registers,
1005 and the exact value says how many bytes are passed in registers.
1007 args[i].pass_on_stack is nonzero if the argument must at least be
1008 computed on the stack. It may then be loaded back into registers
1009 if args[i].reg is nonzero.
1011 These decisions are driven by the FUNCTION_... macros and must agree
1012 with those made by function.c. */
1014 /* See if this argument should be passed by invisible reference. */
1015 if (pass_by_reference (args_so_far, TYPE_MODE (type),
1016 type, argpos < n_named_args))
1022 = reference_callee_copied (args_so_far, TYPE_MODE (type),
1023 type, argpos < n_named_args);
1025 /* If we're compiling a thunk, pass through invisible references
1026 instead of making a copy. */
1027 if (call_from_thunk_p
1029 && !TREE_ADDRESSABLE (type)
1030 && (base = get_base_address (args[i].tree_value))
1031 && (!DECL_P (base) || MEM_P (DECL_RTL (base)))))
1033 /* We can't use sibcalls if a callee-copied argument is
1034 stored in the current function's frame. */
1035 if (!call_from_thunk_p && DECL_P (base) && !TREE_STATIC (base))
1036 *may_tailcall = false;
1038 args[i].tree_value = build_fold_addr_expr (args[i].tree_value);
1039 type = TREE_TYPE (args[i].tree_value);
1041 *ecf_flags &= ~(ECF_CONST | ECF_LIBCALL_BLOCK);
1045 /* We make a copy of the object and pass the address to the
1046 function being called. */
1049 if (!COMPLETE_TYPE_P (type)
1050 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1051 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1052 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1053 STACK_CHECK_MAX_VAR_SIZE))))
1055 /* This is a variable-sized object. Make space on the stack
1057 rtx size_rtx = expr_size (args[i].tree_value);
1059 if (*old_stack_level == 0)
1061 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1062 *old_pending_adj = pending_stack_adjust;
1063 pending_stack_adjust = 0;
1066 copy = gen_rtx_MEM (BLKmode,
1067 allocate_dynamic_stack_space
1068 (size_rtx, NULL_RTX, TYPE_ALIGN (type)));
1069 set_mem_attributes (copy, type, 1);
1072 copy = assign_temp (type, 0, 1, 0);
1074 store_expr (args[i].tree_value, copy, 0, false);
1077 *ecf_flags &= ~(ECF_CONST | ECF_LIBCALL_BLOCK);
1079 *ecf_flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
1082 = build_fold_addr_expr (make_tree (type, copy));
1083 type = TREE_TYPE (args[i].tree_value);
1084 *may_tailcall = false;
1088 mode = TYPE_MODE (type);
1089 unsignedp = TYPE_UNSIGNED (type);
1091 if (targetm.calls.promote_function_args (fndecl ? TREE_TYPE (fndecl) : 0))
1092 mode = promote_mode (type, mode, &unsignedp, 1);
1094 args[i].unsignedp = unsignedp;
1095 args[i].mode = mode;
1097 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1098 argpos < n_named_args);
1099 #ifdef FUNCTION_INCOMING_ARG
1100 /* If this is a sibling call and the machine has register windows, the
1101 register window has to be unwinded before calling the routine, so
1102 arguments have to go into the incoming registers. */
1103 args[i].tail_call_reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1104 argpos < n_named_args);
1106 args[i].tail_call_reg = args[i].reg;
1111 = targetm.calls.arg_partial_bytes (args_so_far, mode, type,
1112 argpos < n_named_args);
1114 args[i].pass_on_stack = targetm.calls.must_pass_in_stack (mode, type);
1116 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1117 it means that we are to pass this arg in the register(s) designated
1118 by the PARALLEL, but also to pass it in the stack. */
1119 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1120 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1121 args[i].pass_on_stack = 1;
1123 /* If this is an addressable type, we must preallocate the stack
1124 since we must evaluate the object into its final location.
1126 If this is to be passed in both registers and the stack, it is simpler
1128 if (TREE_ADDRESSABLE (type)
1129 || (args[i].pass_on_stack && args[i].reg != 0))
1130 *must_preallocate = 1;
1132 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1133 we cannot consider this function call constant. */
1134 if (TREE_ADDRESSABLE (type))
1135 *ecf_flags &= ~ECF_LIBCALL_BLOCK;
1137 /* Compute the stack-size of this argument. */
1138 if (args[i].reg == 0 || args[i].partial != 0
1139 || reg_parm_stack_space > 0
1140 || args[i].pass_on_stack)
1141 locate_and_pad_parm (mode, type,
1142 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1147 args[i].pass_on_stack ? 0 : args[i].partial,
1148 fndecl, args_size, &args[i].locate);
1149 #ifdef BLOCK_REG_PADDING
1151 /* The argument is passed entirely in registers. See at which
1152 end it should be padded. */
1153 args[i].locate.where_pad =
1154 BLOCK_REG_PADDING (mode, type,
1155 int_size_in_bytes (type) <= UNITS_PER_WORD);
1158 /* Update ARGS_SIZE, the total stack space for args so far. */
1160 args_size->constant += args[i].locate.size.constant;
1161 if (args[i].locate.size.var)
1162 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
1164 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1165 have been used, etc. */
1167 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1168 argpos < n_named_args);
1172 /* Update ARGS_SIZE to contain the total size for the argument block.
1173 Return the original constant component of the argument block's size.
1175 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1176 for arguments passed in registers. */
1179 compute_argument_block_size (int reg_parm_stack_space,
1180 struct args_size *args_size,
1181 int preferred_stack_boundary ATTRIBUTE_UNUSED)
1183 int unadjusted_args_size = args_size->constant;
1185 /* For accumulate outgoing args mode we don't need to align, since the frame
1186 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1187 backends from generating misaligned frame sizes. */
1188 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1189 preferred_stack_boundary = STACK_BOUNDARY;
1191 /* Compute the actual size of the argument block required. The variable
1192 and constant sizes must be combined, the size may have to be rounded,
1193 and there may be a minimum required size. */
1197 args_size->var = ARGS_SIZE_TREE (*args_size);
1198 args_size->constant = 0;
1200 preferred_stack_boundary /= BITS_PER_UNIT;
1201 if (preferred_stack_boundary > 1)
1203 /* We don't handle this case yet. To handle it correctly we have
1204 to add the delta, round and subtract the delta.
1205 Currently no machine description requires this support. */
1206 gcc_assert (!(stack_pointer_delta & (preferred_stack_boundary - 1)));
1207 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1210 if (reg_parm_stack_space > 0)
1213 = size_binop (MAX_EXPR, args_size->var,
1214 ssize_int (reg_parm_stack_space));
1216 /* The area corresponding to register parameters is not to count in
1217 the size of the block we need. So make the adjustment. */
1218 if (!OUTGOING_REG_PARM_STACK_SPACE)
1220 = size_binop (MINUS_EXPR, args_size->var,
1221 ssize_int (reg_parm_stack_space));
1226 preferred_stack_boundary /= BITS_PER_UNIT;
1227 if (preferred_stack_boundary < 1)
1228 preferred_stack_boundary = 1;
1229 args_size->constant = (((args_size->constant
1230 + stack_pointer_delta
1231 + preferred_stack_boundary - 1)
1232 / preferred_stack_boundary
1233 * preferred_stack_boundary)
1234 - stack_pointer_delta);
1236 args_size->constant = MAX (args_size->constant,
1237 reg_parm_stack_space);
1239 if (!OUTGOING_REG_PARM_STACK_SPACE)
1240 args_size->constant -= reg_parm_stack_space;
1242 return unadjusted_args_size;
1245 /* Precompute parameters as needed for a function call.
1247 FLAGS is mask of ECF_* constants.
1249 NUM_ACTUALS is the number of arguments.
1251 ARGS is an array containing information for each argument; this
1252 routine fills in the INITIAL_VALUE and VALUE fields for each
1253 precomputed argument. */
1256 precompute_arguments (int flags, int num_actuals, struct arg_data *args)
1260 /* If this is a libcall, then precompute all arguments so that we do not
1261 get extraneous instructions emitted as part of the libcall sequence. */
1263 /* If we preallocated the stack space, and some arguments must be passed
1264 on the stack, then we must precompute any parameter which contains a
1265 function call which will store arguments on the stack.
1266 Otherwise, evaluating the parameter may clobber previous parameters
1267 which have already been stored into the stack. (we have code to avoid
1268 such case by saving the outgoing stack arguments, but it results in
1270 if ((flags & ECF_LIBCALL_BLOCK) == 0 && !ACCUMULATE_OUTGOING_ARGS)
1273 for (i = 0; i < num_actuals; i++)
1275 enum machine_mode mode;
1277 if ((flags & ECF_LIBCALL_BLOCK) == 0
1278 && TREE_CODE (args[i].tree_value) != CALL_EXPR)
1281 /* If this is an addressable type, we cannot pre-evaluate it. */
1282 gcc_assert (!TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)));
1284 args[i].initial_value = args[i].value
1285 = expand_normal (args[i].tree_value);
1287 mode = TYPE_MODE (TREE_TYPE (args[i].tree_value));
1288 if (mode != args[i].mode)
1291 = convert_modes (args[i].mode, mode,
1292 args[i].value, args[i].unsignedp);
1293 #if defined(PROMOTE_FUNCTION_MODE) && !defined(PROMOTE_MODE)
1294 /* CSE will replace this only if it contains args[i].value
1295 pseudo, so convert it down to the declared mode using
1297 if (REG_P (args[i].value)
1298 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1300 args[i].initial_value
1301 = gen_lowpart_SUBREG (mode, args[i].value);
1302 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1303 SUBREG_PROMOTED_UNSIGNED_SET (args[i].initial_value,
1311 /* Given the current state of MUST_PREALLOCATE and information about
1312 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1313 compute and return the final value for MUST_PREALLOCATE. */
1316 finalize_must_preallocate (int must_preallocate, int num_actuals,
1317 struct arg_data *args, struct args_size *args_size)
1319 /* See if we have or want to preallocate stack space.
1321 If we would have to push a partially-in-regs parm
1322 before other stack parms, preallocate stack space instead.
1324 If the size of some parm is not a multiple of the required stack
1325 alignment, we must preallocate.
1327 If the total size of arguments that would otherwise create a copy in
1328 a temporary (such as a CALL) is more than half the total argument list
1329 size, preallocation is faster.
1331 Another reason to preallocate is if we have a machine (like the m88k)
1332 where stack alignment is required to be maintained between every
1333 pair of insns, not just when the call is made. However, we assume here
1334 that such machines either do not have push insns (and hence preallocation
1335 would occur anyway) or the problem is taken care of with
1338 if (! must_preallocate)
1340 int partial_seen = 0;
1341 int copy_to_evaluate_size = 0;
1344 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1346 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1348 else if (partial_seen && args[i].reg == 0)
1349 must_preallocate = 1;
1351 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1352 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1353 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1354 || TREE_CODE (args[i].tree_value) == COND_EXPR
1355 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1356 copy_to_evaluate_size
1357 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1360 if (copy_to_evaluate_size * 2 >= args_size->constant
1361 && args_size->constant > 0)
1362 must_preallocate = 1;
1364 return must_preallocate;
1367 /* If we preallocated stack space, compute the address of each argument
1368 and store it into the ARGS array.
1370 We need not ensure it is a valid memory address here; it will be
1371 validized when it is used.
1373 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1376 compute_argument_addresses (struct arg_data *args, rtx argblock, int num_actuals)
1380 rtx arg_reg = argblock;
1381 int i, arg_offset = 0;
1383 if (GET_CODE (argblock) == PLUS)
1384 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1386 for (i = 0; i < num_actuals; i++)
1388 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
1389 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
1391 unsigned int align, boundary;
1392 unsigned int units_on_stack = 0;
1393 enum machine_mode partial_mode = VOIDmode;
1395 /* Skip this parm if it will not be passed on the stack. */
1396 if (! args[i].pass_on_stack
1398 && args[i].partial == 0)
1401 if (GET_CODE (offset) == CONST_INT)
1402 addr = plus_constant (arg_reg, INTVAL (offset));
1404 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1406 addr = plus_constant (addr, arg_offset);
1408 if (args[i].partial != 0)
1410 /* Only part of the parameter is being passed on the stack.
1411 Generate a simple memory reference of the correct size. */
1412 units_on_stack = args[i].locate.size.constant;
1413 partial_mode = mode_for_size (units_on_stack * BITS_PER_UNIT,
1415 args[i].stack = gen_rtx_MEM (partial_mode, addr);
1416 set_mem_size (args[i].stack, GEN_INT (units_on_stack));
1420 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1421 set_mem_attributes (args[i].stack,
1422 TREE_TYPE (args[i].tree_value), 1);
1424 align = BITS_PER_UNIT;
1425 boundary = args[i].locate.boundary;
1426 if (args[i].locate.where_pad != downward)
1428 else if (GET_CODE (offset) == CONST_INT)
1430 align = INTVAL (offset) * BITS_PER_UNIT | boundary;
1431 align = align & -align;
1433 set_mem_align (args[i].stack, align);
1435 if (GET_CODE (slot_offset) == CONST_INT)
1436 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1438 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1440 addr = plus_constant (addr, arg_offset);
1442 if (args[i].partial != 0)
1444 /* Only part of the parameter is being passed on the stack.
1445 Generate a simple memory reference of the correct size.
1447 args[i].stack_slot = gen_rtx_MEM (partial_mode, addr);
1448 set_mem_size (args[i].stack_slot, GEN_INT (units_on_stack));
1452 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1453 set_mem_attributes (args[i].stack_slot,
1454 TREE_TYPE (args[i].tree_value), 1);
1456 set_mem_align (args[i].stack_slot, args[i].locate.boundary);
1458 /* Function incoming arguments may overlap with sibling call
1459 outgoing arguments and we cannot allow reordering of reads
1460 from function arguments with stores to outgoing arguments
1461 of sibling calls. */
1462 set_mem_alias_set (args[i].stack, 0);
1463 set_mem_alias_set (args[i].stack_slot, 0);
1468 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1469 in a call instruction.
1471 FNDECL is the tree node for the target function. For an indirect call
1472 FNDECL will be NULL_TREE.
1474 ADDR is the operand 0 of CALL_EXPR for this call. */
1477 rtx_for_function_call (tree fndecl, tree addr)
1481 /* Get the function to call, in the form of RTL. */
1484 /* If this is the first use of the function, see if we need to
1485 make an external definition for it. */
1486 if (!TREE_USED (fndecl) && fndecl != current_function_decl)
1488 assemble_external (fndecl);
1489 TREE_USED (fndecl) = 1;
1492 /* Get a SYMBOL_REF rtx for the function address. */
1493 funexp = XEXP (DECL_RTL (fndecl), 0);
1496 /* Generate an rtx (probably a pseudo-register) for the address. */
1499 funexp = expand_normal (addr);
1500 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1505 /* Return true if and only if SIZE storage units (usually bytes)
1506 starting from address ADDR overlap with already clobbered argument
1507 area. This function is used to determine if we should give up a
1511 mem_overlaps_already_clobbered_arg_p (rtx addr, unsigned HOST_WIDE_INT size)
1515 if (addr == crtl->args.internal_arg_pointer)
1517 else if (GET_CODE (addr) == PLUS
1518 && XEXP (addr, 0) == crtl->args.internal_arg_pointer
1519 && GET_CODE (XEXP (addr, 1)) == CONST_INT)
1520 i = INTVAL (XEXP (addr, 1));
1521 /* Return true for arg pointer based indexed addressing. */
1522 else if (GET_CODE (addr) == PLUS
1523 && (XEXP (addr, 0) == crtl->args.internal_arg_pointer
1524 || XEXP (addr, 1) == crtl->args.internal_arg_pointer))
1529 #ifdef ARGS_GROW_DOWNWARD
1534 unsigned HOST_WIDE_INT k;
1536 for (k = 0; k < size; k++)
1537 if (i + k < stored_args_map->n_bits
1538 && TEST_BIT (stored_args_map, i + k))
1545 /* Do the register loads required for any wholly-register parms or any
1546 parms which are passed both on the stack and in a register. Their
1547 expressions were already evaluated.
1549 Mark all register-parms as living through the call, putting these USE
1550 insns in the CALL_INSN_FUNCTION_USAGE field.
1552 When IS_SIBCALL, perform the check_sibcall_argument_overlap
1553 checking, setting *SIBCALL_FAILURE if appropriate. */
1556 load_register_parameters (struct arg_data *args, int num_actuals,
1557 rtx *call_fusage, int flags, int is_sibcall,
1558 int *sibcall_failure)
1562 for (i = 0; i < num_actuals; i++)
1564 rtx reg = ((flags & ECF_SIBCALL)
1565 ? args[i].tail_call_reg : args[i].reg);
1568 int partial = args[i].partial;
1571 rtx before_arg = get_last_insn ();
1572 /* Set non-negative if we must move a word at a time, even if
1573 just one word (e.g, partial == 4 && mode == DFmode). Set
1574 to -1 if we just use a normal move insn. This value can be
1575 zero if the argument is a zero size structure. */
1577 if (GET_CODE (reg) == PARALLEL)
1581 gcc_assert (partial % UNITS_PER_WORD == 0);
1582 nregs = partial / UNITS_PER_WORD;
1584 else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
1586 size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1587 nregs = (size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1590 size = GET_MODE_SIZE (args[i].mode);
1592 /* Handle calls that pass values in multiple non-contiguous
1593 locations. The Irix 6 ABI has examples of this. */
1595 if (GET_CODE (reg) == PARALLEL)
1596 emit_group_move (reg, args[i].parallel_value);
1598 /* If simple case, just do move. If normal partial, store_one_arg
1599 has already loaded the register for us. In all other cases,
1600 load the register(s) from memory. */
1602 else if (nregs == -1)
1604 emit_move_insn (reg, args[i].value);
1605 #ifdef BLOCK_REG_PADDING
1606 /* Handle case where we have a value that needs shifting
1607 up to the msb. eg. a QImode value and we're padding
1608 upward on a BYTES_BIG_ENDIAN machine. */
1609 if (size < UNITS_PER_WORD
1610 && (args[i].locate.where_pad
1611 == (BYTES_BIG_ENDIAN ? upward : downward)))
1614 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
1616 /* Assigning REG here rather than a temp makes CALL_FUSAGE
1617 report the whole reg as used. Strictly speaking, the
1618 call only uses SIZE bytes at the msb end, but it doesn't
1619 seem worth generating rtl to say that. */
1620 reg = gen_rtx_REG (word_mode, REGNO (reg));
1621 x = expand_shift (LSHIFT_EXPR, word_mode, reg,
1622 build_int_cst (NULL_TREE, shift),
1625 emit_move_insn (reg, x);
1630 /* If we have pre-computed the values to put in the registers in
1631 the case of non-aligned structures, copy them in now. */
1633 else if (args[i].n_aligned_regs != 0)
1634 for (j = 0; j < args[i].n_aligned_regs; j++)
1635 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1636 args[i].aligned_regs[j]);
1638 else if (partial == 0 || args[i].pass_on_stack)
1640 rtx mem = validize_mem (args[i].value);
1642 /* Check for overlap with already clobbered argument area. */
1644 && mem_overlaps_already_clobbered_arg_p (XEXP (args[i].value, 0),
1646 *sibcall_failure = 1;
1648 /* Handle a BLKmode that needs shifting. */
1649 if (nregs == 1 && size < UNITS_PER_WORD
1650 #ifdef BLOCK_REG_PADDING
1651 && args[i].locate.where_pad == downward
1657 rtx tem = operand_subword_force (mem, 0, args[i].mode);
1658 rtx ri = gen_rtx_REG (word_mode, REGNO (reg));
1659 rtx x = gen_reg_rtx (word_mode);
1660 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
1661 enum tree_code dir = BYTES_BIG_ENDIAN ? RSHIFT_EXPR
1664 emit_move_insn (x, tem);
1665 x = expand_shift (dir, word_mode, x,
1666 build_int_cst (NULL_TREE, shift),
1669 emit_move_insn (ri, x);
1672 move_block_to_reg (REGNO (reg), mem, nregs, args[i].mode);
1675 /* When a parameter is a block, and perhaps in other cases, it is
1676 possible that it did a load from an argument slot that was
1677 already clobbered. */
1679 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
1680 *sibcall_failure = 1;
1682 /* Handle calls that pass values in multiple non-contiguous
1683 locations. The Irix 6 ABI has examples of this. */
1684 if (GET_CODE (reg) == PARALLEL)
1685 use_group_regs (call_fusage, reg);
1686 else if (nregs == -1)
1687 use_reg (call_fusage, reg);
1689 use_regs (call_fusage, REGNO (reg), nregs);
1694 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1695 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1696 bytes, then we would need to push some additional bytes to pad the
1697 arguments. So, we compute an adjust to the stack pointer for an
1698 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1699 bytes. Then, when the arguments are pushed the stack will be perfectly
1700 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1701 be popped after the call. Returns the adjustment. */
1704 combine_pending_stack_adjustment_and_call (int unadjusted_args_size,
1705 struct args_size *args_size,
1706 unsigned int preferred_unit_stack_boundary)
1708 /* The number of bytes to pop so that the stack will be
1709 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1710 HOST_WIDE_INT adjustment;
1711 /* The alignment of the stack after the arguments are pushed, if we
1712 just pushed the arguments without adjust the stack here. */
1713 unsigned HOST_WIDE_INT unadjusted_alignment;
1715 unadjusted_alignment
1716 = ((stack_pointer_delta + unadjusted_args_size)
1717 % preferred_unit_stack_boundary);
1719 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1720 as possible -- leaving just enough left to cancel out the
1721 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1722 PENDING_STACK_ADJUST is non-negative, and congruent to
1723 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1725 /* Begin by trying to pop all the bytes. */
1726 unadjusted_alignment
1727 = (unadjusted_alignment
1728 - (pending_stack_adjust % preferred_unit_stack_boundary));
1729 adjustment = pending_stack_adjust;
1730 /* Push enough additional bytes that the stack will be aligned
1731 after the arguments are pushed. */
1732 if (preferred_unit_stack_boundary > 1)
1734 if (unadjusted_alignment > 0)
1735 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1737 adjustment += unadjusted_alignment;
1740 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1741 bytes after the call. The right number is the entire
1742 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1743 by the arguments in the first place. */
1745 = pending_stack_adjust - adjustment + unadjusted_args_size;
1750 /* Scan X expression if it does not dereference any argument slots
1751 we already clobbered by tail call arguments (as noted in stored_args_map
1753 Return nonzero if X expression dereferences such argument slots,
1757 check_sibcall_argument_overlap_1 (rtx x)
1766 code = GET_CODE (x);
1769 return mem_overlaps_already_clobbered_arg_p (XEXP (x, 0),
1770 GET_MODE_SIZE (GET_MODE (x)));
1772 /* Scan all subexpressions. */
1773 fmt = GET_RTX_FORMAT (code);
1774 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
1778 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
1781 else if (*fmt == 'E')
1783 for (j = 0; j < XVECLEN (x, i); j++)
1784 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
1791 /* Scan sequence after INSN if it does not dereference any argument slots
1792 we already clobbered by tail call arguments (as noted in stored_args_map
1793 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
1794 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
1795 should be 0). Return nonzero if sequence after INSN dereferences such argument
1796 slots, zero otherwise. */
1799 check_sibcall_argument_overlap (rtx insn, struct arg_data *arg, int mark_stored_args_map)
1803 if (insn == NULL_RTX)
1804 insn = get_insns ();
1806 insn = NEXT_INSN (insn);
1808 for (; insn; insn = NEXT_INSN (insn))
1810 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
1813 if (mark_stored_args_map)
1815 #ifdef ARGS_GROW_DOWNWARD
1816 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
1818 low = arg->locate.slot_offset.constant;
1821 for (high = low + arg->locate.size.constant; low < high; low++)
1822 SET_BIT (stored_args_map, low);
1824 return insn != NULL_RTX;
1827 /* Given that a function returns a value of mode MODE at the most
1828 significant end of hard register VALUE, shift VALUE left or right
1829 as specified by LEFT_P. Return true if some action was needed. */
1832 shift_return_value (enum machine_mode mode, bool left_p, rtx value)
1834 HOST_WIDE_INT shift;
1836 gcc_assert (REG_P (value) && HARD_REGISTER_P (value));
1837 shift = GET_MODE_BITSIZE (GET_MODE (value)) - GET_MODE_BITSIZE (mode);
1841 /* Use ashr rather than lshr for right shifts. This is for the benefit
1842 of the MIPS port, which requires SImode values to be sign-extended
1843 when stored in 64-bit registers. */
1844 if (!force_expand_binop (GET_MODE (value), left_p ? ashl_optab : ashr_optab,
1845 value, GEN_INT (shift), value, 1, OPTAB_WIDEN))
1850 /* If X is a likely-spilled register value, copy it to a pseudo
1851 register and return that register. Return X otherwise. */
1854 avoid_likely_spilled_reg (rtx x)
1859 && HARD_REGISTER_P (x)
1860 && CLASS_LIKELY_SPILLED_P (REGNO_REG_CLASS (REGNO (x))))
1862 /* Make sure that we generate a REG rather than a CONCAT.
1863 Moves into CONCATs can need nontrivial instructions,
1864 and the whole point of this function is to avoid
1865 using the hard register directly in such a situation. */
1866 generating_concat_p = 0;
1867 new = gen_reg_rtx (GET_MODE (x));
1868 generating_concat_p = 1;
1869 emit_move_insn (new, x);
1875 /* Generate all the code for a CALL_EXPR exp
1876 and return an rtx for its value.
1877 Store the value in TARGET (specified as an rtx) if convenient.
1878 If the value is stored in TARGET then TARGET is returned.
1879 If IGNORE is nonzero, then we ignore the value of the function call. */
1882 expand_call (tree exp, rtx target, int ignore)
1884 /* Nonzero if we are currently expanding a call. */
1885 static int currently_expanding_call = 0;
1887 /* RTX for the function to be called. */
1889 /* Sequence of insns to perform a normal "call". */
1890 rtx normal_call_insns = NULL_RTX;
1891 /* Sequence of insns to perform a tail "call". */
1892 rtx tail_call_insns = NULL_RTX;
1893 /* Data type of the function. */
1895 tree type_arg_types;
1896 /* Declaration of the function being called,
1897 or 0 if the function is computed (not known by name). */
1899 /* The type of the function being called. */
1901 bool try_tail_call = CALL_EXPR_TAILCALL (exp);
1904 /* Register in which non-BLKmode value will be returned,
1905 or 0 if no value or if value is BLKmode. */
1907 /* Address where we should return a BLKmode value;
1908 0 if value not BLKmode. */
1909 rtx structure_value_addr = 0;
1910 /* Nonzero if that address is being passed by treating it as
1911 an extra, implicit first parameter. Otherwise,
1912 it is passed by being copied directly into struct_value_rtx. */
1913 int structure_value_addr_parm = 0;
1914 /* Holds the value of implicit argument for the struct value. */
1915 tree structure_value_addr_value = NULL_TREE;
1916 /* Size of aggregate value wanted, or zero if none wanted
1917 or if we are using the non-reentrant PCC calling convention
1918 or expecting the value in registers. */
1919 HOST_WIDE_INT struct_value_size = 0;
1920 /* Nonzero if called function returns an aggregate in memory PCC style,
1921 by returning the address of where to find it. */
1922 int pcc_struct_value = 0;
1923 rtx struct_value = 0;
1925 /* Number of actual parameters in this call, including struct value addr. */
1927 /* Number of named args. Args after this are anonymous ones
1928 and they must all go on the stack. */
1930 /* Number of complex actual arguments that need to be split. */
1931 int num_complex_actuals = 0;
1933 /* Vector of information about each argument.
1934 Arguments are numbered in the order they will be pushed,
1935 not the order they are written. */
1936 struct arg_data *args;
1938 /* Total size in bytes of all the stack-parms scanned so far. */
1939 struct args_size args_size;
1940 struct args_size adjusted_args_size;
1941 /* Size of arguments before any adjustments (such as rounding). */
1942 int unadjusted_args_size;
1943 /* Data on reg parms scanned so far. */
1944 CUMULATIVE_ARGS args_so_far;
1945 /* Nonzero if a reg parm has been scanned. */
1947 /* Nonzero if this is an indirect function call. */
1949 /* Nonzero if we must avoid push-insns in the args for this call.
1950 If stack space is allocated for register parameters, but not by the
1951 caller, then it is preallocated in the fixed part of the stack frame.
1952 So the entire argument block must then be preallocated (i.e., we
1953 ignore PUSH_ROUNDING in that case). */
1955 int must_preallocate = !PUSH_ARGS;
1957 /* Size of the stack reserved for parameter registers. */
1958 int reg_parm_stack_space = 0;
1960 /* Address of space preallocated for stack parms
1961 (on machines that lack push insns), or 0 if space not preallocated. */
1964 /* Mask of ECF_ flags. */
1966 #ifdef REG_PARM_STACK_SPACE
1967 /* Define the boundary of the register parm stack space that needs to be
1969 int low_to_save, high_to_save;
1970 rtx save_area = 0; /* Place that it is saved */
1973 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
1974 char *initial_stack_usage_map = stack_usage_map;
1975 char *stack_usage_map_buf = NULL;
1977 int old_stack_allocated;
1979 /* State variables to track stack modifications. */
1980 rtx old_stack_level = 0;
1981 int old_stack_arg_under_construction = 0;
1982 int old_pending_adj = 0;
1983 int old_inhibit_defer_pop = inhibit_defer_pop;
1985 /* Some stack pointer alterations we make are performed via
1986 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
1987 which we then also need to save/restore along the way. */
1988 int old_stack_pointer_delta = 0;
1991 tree p = CALL_EXPR_FN (exp);
1992 tree addr = CALL_EXPR_FN (exp);
1994 /* The alignment of the stack, in bits. */
1995 unsigned HOST_WIDE_INT preferred_stack_boundary;
1996 /* The alignment of the stack, in bytes. */
1997 unsigned HOST_WIDE_INT preferred_unit_stack_boundary;
1998 /* The static chain value to use for this call. */
1999 rtx static_chain_value;
2000 /* See if this is "nothrow" function call. */
2001 if (TREE_NOTHROW (exp))
2002 flags |= ECF_NOTHROW;
2004 /* See if we can find a DECL-node for the actual function, and get the
2005 function attributes (flags) from the function decl or type node. */
2006 fndecl = get_callee_fndecl (exp);
2009 fntype = TREE_TYPE (fndecl);
2010 flags |= flags_from_decl_or_type (fndecl);
2014 fntype = TREE_TYPE (TREE_TYPE (p));
2015 flags |= flags_from_decl_or_type (fntype);
2018 struct_value = targetm.calls.struct_value_rtx (fntype, 0);
2020 /* Warn if this value is an aggregate type,
2021 regardless of which calling convention we are using for it. */
2022 if (AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2023 warning (OPT_Waggregate_return, "function call has aggregate value");
2025 /* If the result of a pure or const function call is ignored (or void),
2026 and none of its arguments are volatile, we can avoid expanding the
2027 call and just evaluate the arguments for side-effects. */
2028 if ((flags & (ECF_CONST | ECF_PURE))
2029 && (ignore || target == const0_rtx
2030 || TYPE_MODE (TREE_TYPE (exp)) == VOIDmode))
2032 bool volatilep = false;
2034 call_expr_arg_iterator iter;
2036 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2037 if (TREE_THIS_VOLATILE (arg))
2045 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2046 expand_expr (arg, const0_rtx, VOIDmode, EXPAND_NORMAL);
2051 #ifdef REG_PARM_STACK_SPACE
2052 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2055 if (!OUTGOING_REG_PARM_STACK_SPACE && reg_parm_stack_space > 0 && PUSH_ARGS)
2056 must_preallocate = 1;
2058 /* Set up a place to return a structure. */
2060 /* Cater to broken compilers. */
2061 if (aggregate_value_p (exp, fndecl))
2063 /* This call returns a big structure. */
2064 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
2066 #ifdef PCC_STATIC_STRUCT_RETURN
2068 pcc_struct_value = 1;
2070 #else /* not PCC_STATIC_STRUCT_RETURN */
2072 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2074 if (target && MEM_P (target) && CALL_EXPR_RETURN_SLOT_OPT (exp))
2075 structure_value_addr = XEXP (target, 0);
2078 /* For variable-sized objects, we must be called with a target
2079 specified. If we were to allocate space on the stack here,
2080 we would have no way of knowing when to free it. */
2081 rtx d = assign_temp (TREE_TYPE (exp), 0, 1, 1);
2083 mark_temp_addr_taken (d);
2084 structure_value_addr = XEXP (d, 0);
2088 #endif /* not PCC_STATIC_STRUCT_RETURN */
2091 /* Figure out the amount to which the stack should be aligned. */
2092 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2095 struct cgraph_rtl_info *i = cgraph_rtl_info (fndecl);
2096 if (i && i->preferred_incoming_stack_boundary)
2097 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
2100 /* Operand 0 is a pointer-to-function; get the type of the function. */
2101 funtype = TREE_TYPE (addr);
2102 gcc_assert (POINTER_TYPE_P (funtype));
2103 funtype = TREE_TYPE (funtype);
2105 /* Count whether there are actual complex arguments that need to be split
2106 into their real and imaginary parts. Munge the type_arg_types
2107 appropriately here as well. */
2108 if (targetm.calls.split_complex_arg)
2110 call_expr_arg_iterator iter;
2112 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2114 tree type = TREE_TYPE (arg);
2115 if (type && TREE_CODE (type) == COMPLEX_TYPE
2116 && targetm.calls.split_complex_arg (type))
2117 num_complex_actuals++;
2119 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
2122 type_arg_types = TYPE_ARG_TYPES (funtype);
2124 if (flags & ECF_MAY_BE_ALLOCA)
2125 cfun->calls_alloca = 1;
2127 /* If struct_value_rtx is 0, it means pass the address
2128 as if it were an extra parameter. Put the argument expression
2129 in structure_value_addr_value. */
2130 if (structure_value_addr && struct_value == 0)
2132 /* If structure_value_addr is a REG other than
2133 virtual_outgoing_args_rtx, we can use always use it. If it
2134 is not a REG, we must always copy it into a register.
2135 If it is virtual_outgoing_args_rtx, we must copy it to another
2136 register in some cases. */
2137 rtx temp = (!REG_P (structure_value_addr)
2138 || (ACCUMULATE_OUTGOING_ARGS
2139 && stack_arg_under_construction
2140 && structure_value_addr == virtual_outgoing_args_rtx)
2141 ? copy_addr_to_reg (convert_memory_address
2142 (Pmode, structure_value_addr))
2143 : structure_value_addr);
2145 structure_value_addr_value =
2146 make_tree (build_pointer_type (TREE_TYPE (funtype)), temp);
2147 structure_value_addr_parm = 1;
2150 /* Count the arguments and set NUM_ACTUALS. */
2152 call_expr_nargs (exp) + num_complex_actuals + structure_value_addr_parm;
2154 /* Compute number of named args.
2155 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
2157 if (type_arg_types != 0)
2159 = (list_length (type_arg_types)
2160 /* Count the struct value address, if it is passed as a parm. */
2161 + structure_value_addr_parm);
2163 /* If we know nothing, treat all args as named. */
2164 n_named_args = num_actuals;
2166 /* Start updating where the next arg would go.
2168 On some machines (such as the PA) indirect calls have a different
2169 calling convention than normal calls. The fourth argument in
2170 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2172 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, fndecl, n_named_args);
2174 /* Now possibly adjust the number of named args.
2175 Normally, don't include the last named arg if anonymous args follow.
2176 We do include the last named arg if
2177 targetm.calls.strict_argument_naming() returns nonzero.
2178 (If no anonymous args follow, the result of list_length is actually
2179 one too large. This is harmless.)
2181 If targetm.calls.pretend_outgoing_varargs_named() returns
2182 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2183 this machine will be able to place unnamed args that were passed
2184 in registers into the stack. So treat all args as named. This
2185 allows the insns emitting for a specific argument list to be
2186 independent of the function declaration.
2188 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2189 we do not have any reliable way to pass unnamed args in
2190 registers, so we must force them into memory. */
2192 if (type_arg_types != 0
2193 && targetm.calls.strict_argument_naming (&args_so_far))
2195 else if (type_arg_types != 0
2196 && ! targetm.calls.pretend_outgoing_varargs_named (&args_so_far))
2197 /* Don't include the last named arg. */
2200 /* Treat all args as named. */
2201 n_named_args = num_actuals;
2203 /* Make a vector to hold all the information about each arg. */
2204 args = alloca (num_actuals * sizeof (struct arg_data));
2205 memset (args, 0, num_actuals * sizeof (struct arg_data));
2207 /* Build up entries in the ARGS array, compute the size of the
2208 arguments into ARGS_SIZE, etc. */
2209 initialize_argument_information (num_actuals, args, &args_size,
2211 structure_value_addr_value, fndecl,
2212 &args_so_far, reg_parm_stack_space,
2213 &old_stack_level, &old_pending_adj,
2214 &must_preallocate, &flags,
2215 &try_tail_call, CALL_FROM_THUNK_P (exp));
2219 /* If this function requires a variable-sized argument list, don't
2220 try to make a cse'able block for this call. We may be able to
2221 do this eventually, but it is too complicated to keep track of
2222 what insns go in the cse'able block and which don't. */
2224 flags &= ~ECF_LIBCALL_BLOCK;
2225 must_preallocate = 1;
2228 /* Now make final decision about preallocating stack space. */
2229 must_preallocate = finalize_must_preallocate (must_preallocate,
2233 /* If the structure value address will reference the stack pointer, we
2234 must stabilize it. We don't need to do this if we know that we are
2235 not going to adjust the stack pointer in processing this call. */
2237 if (structure_value_addr
2238 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2239 || reg_mentioned_p (virtual_outgoing_args_rtx,
2240 structure_value_addr))
2242 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2243 structure_value_addr = copy_to_reg (structure_value_addr);
2245 /* Tail calls can make things harder to debug, and we've traditionally
2246 pushed these optimizations into -O2. Don't try if we're already
2247 expanding a call, as that means we're an argument. Don't try if
2248 there's cleanups, as we know there's code to follow the call. */
2250 if (currently_expanding_call++ != 0
2251 || !flag_optimize_sibling_calls
2253 || lookup_stmt_eh_region (exp) >= 0
2254 || dbg_cnt (tail_call) == false)
2257 /* Rest of purposes for tail call optimizations to fail. */
2259 #ifdef HAVE_sibcall_epilogue
2260 !HAVE_sibcall_epilogue
2265 /* Doing sibling call optimization needs some work, since
2266 structure_value_addr can be allocated on the stack.
2267 It does not seem worth the effort since few optimizable
2268 sibling calls will return a structure. */
2269 || structure_value_addr != NULL_RTX
2270 /* Check whether the target is able to optimize the call
2272 || !targetm.function_ok_for_sibcall (fndecl, exp)
2273 /* Functions that do not return exactly once may not be sibcall
2275 || (flags & (ECF_RETURNS_TWICE | ECF_NORETURN))
2276 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr)))
2277 /* If the called function is nested in the current one, it might access
2278 some of the caller's arguments, but could clobber them beforehand if
2279 the argument areas are shared. */
2280 || (fndecl && decl_function_context (fndecl) == current_function_decl)
2281 /* If this function requires more stack slots than the current
2282 function, we cannot change it into a sibling call.
2283 crtl->args.pretend_args_size is not part of the
2284 stack allocated by our caller. */
2285 || args_size.constant > (crtl->args.size
2286 - crtl->args.pretend_args_size)
2287 /* If the callee pops its own arguments, then it must pop exactly
2288 the same number of arguments as the current function. */
2289 || (RETURN_POPS_ARGS (fndecl, funtype, args_size.constant)
2290 != RETURN_POPS_ARGS (current_function_decl,
2291 TREE_TYPE (current_function_decl),
2293 || !lang_hooks.decls.ok_for_sibcall (fndecl))
2296 /* Ensure current function's preferred stack boundary is at least
2297 what we need. We don't have to increase alignment for recursive
2299 if (crtl->preferred_stack_boundary < preferred_stack_boundary
2300 && fndecl != current_function_decl)
2301 crtl->preferred_stack_boundary = preferred_stack_boundary;
2303 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2305 /* We want to make two insn chains; one for a sibling call, the other
2306 for a normal call. We will select one of the two chains after
2307 initial RTL generation is complete. */
2308 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
2310 int sibcall_failure = 0;
2311 /* We want to emit any pending stack adjustments before the tail
2312 recursion "call". That way we know any adjustment after the tail
2313 recursion call can be ignored if we indeed use the tail
2315 int save_pending_stack_adjust = 0;
2316 int save_stack_pointer_delta = 0;
2318 rtx before_call, next_arg_reg, after_args;
2322 /* State variables we need to save and restore between
2324 save_pending_stack_adjust = pending_stack_adjust;
2325 save_stack_pointer_delta = stack_pointer_delta;
2328 flags &= ~ECF_SIBCALL;
2330 flags |= ECF_SIBCALL;
2332 /* Other state variables that we must reinitialize each time
2333 through the loop (that are not initialized by the loop itself). */
2337 /* Start a new sequence for the normal call case.
2339 From this point on, if the sibling call fails, we want to set
2340 sibcall_failure instead of continuing the loop. */
2343 /* Don't let pending stack adjusts add up to too much.
2344 Also, do all pending adjustments now if there is any chance
2345 this might be a call to alloca or if we are expanding a sibling
2347 Also do the adjustments before a throwing call, otherwise
2348 exception handling can fail; PR 19225. */
2349 if (pending_stack_adjust >= 32
2350 || (pending_stack_adjust > 0
2351 && (flags & ECF_MAY_BE_ALLOCA))
2352 || (pending_stack_adjust > 0
2353 && flag_exceptions && !(flags & ECF_NOTHROW))
2355 do_pending_stack_adjust ();
2357 /* When calling a const function, we must pop the stack args right away,
2358 so that the pop is deleted or moved with the call. */
2359 if (pass && (flags & ECF_LIBCALL_BLOCK))
2362 /* Precompute any arguments as needed. */
2364 precompute_arguments (flags, num_actuals, args);
2366 /* Now we are about to start emitting insns that can be deleted
2367 if a libcall is deleted. */
2368 if (pass && (flags & (ECF_LIBCALL_BLOCK | ECF_MALLOC)))
2371 if (pass == 0 && crtl->stack_protect_guard)
2372 stack_protect_epilogue ();
2374 adjusted_args_size = args_size;
2375 /* Compute the actual size of the argument block required. The variable
2376 and constant sizes must be combined, the size may have to be rounded,
2377 and there may be a minimum required size. When generating a sibcall
2378 pattern, do not round up, since we'll be re-using whatever space our
2380 unadjusted_args_size
2381 = compute_argument_block_size (reg_parm_stack_space,
2382 &adjusted_args_size,
2384 : preferred_stack_boundary));
2386 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2388 /* The argument block when performing a sibling call is the
2389 incoming argument block. */
2392 argblock = virtual_incoming_args_rtx;
2394 #ifdef STACK_GROWS_DOWNWARD
2395 = plus_constant (argblock, crtl->args.pretend_args_size);
2397 = plus_constant (argblock, -crtl->args.pretend_args_size);
2399 stored_args_map = sbitmap_alloc (args_size.constant);
2400 sbitmap_zero (stored_args_map);
2403 /* If we have no actual push instructions, or shouldn't use them,
2404 make space for all args right now. */
2405 else if (adjusted_args_size.var != 0)
2407 if (old_stack_level == 0)
2409 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2410 old_stack_pointer_delta = stack_pointer_delta;
2411 old_pending_adj = pending_stack_adjust;
2412 pending_stack_adjust = 0;
2413 /* stack_arg_under_construction says whether a stack arg is
2414 being constructed at the old stack level. Pushing the stack
2415 gets a clean outgoing argument block. */
2416 old_stack_arg_under_construction = stack_arg_under_construction;
2417 stack_arg_under_construction = 0;
2419 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2423 /* Note that we must go through the motions of allocating an argument
2424 block even if the size is zero because we may be storing args
2425 in the area reserved for register arguments, which may be part of
2428 int needed = adjusted_args_size.constant;
2430 /* Store the maximum argument space used. It will be pushed by
2431 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2434 if (needed > crtl->outgoing_args_size)
2435 crtl->outgoing_args_size = needed;
2437 if (must_preallocate)
2439 if (ACCUMULATE_OUTGOING_ARGS)
2441 /* Since the stack pointer will never be pushed, it is
2442 possible for the evaluation of a parm to clobber
2443 something we have already written to the stack.
2444 Since most function calls on RISC machines do not use
2445 the stack, this is uncommon, but must work correctly.
2447 Therefore, we save any area of the stack that was already
2448 written and that we are using. Here we set up to do this
2449 by making a new stack usage map from the old one. The
2450 actual save will be done by store_one_arg.
2452 Another approach might be to try to reorder the argument
2453 evaluations to avoid this conflicting stack usage. */
2455 /* Since we will be writing into the entire argument area,
2456 the map must be allocated for its entire size, not just
2457 the part that is the responsibility of the caller. */
2458 if (!OUTGOING_REG_PARM_STACK_SPACE)
2459 needed += reg_parm_stack_space;
2461 #ifdef ARGS_GROW_DOWNWARD
2462 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2465 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2468 if (stack_usage_map_buf)
2469 free (stack_usage_map_buf);
2470 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
2471 stack_usage_map = stack_usage_map_buf;
2473 if (initial_highest_arg_in_use)
2474 memcpy (stack_usage_map, initial_stack_usage_map,
2475 initial_highest_arg_in_use);
2477 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2478 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2479 (highest_outgoing_arg_in_use
2480 - initial_highest_arg_in_use));
2483 /* The address of the outgoing argument list must not be
2484 copied to a register here, because argblock would be left
2485 pointing to the wrong place after the call to
2486 allocate_dynamic_stack_space below. */
2488 argblock = virtual_outgoing_args_rtx;
2492 if (inhibit_defer_pop == 0)
2494 /* Try to reuse some or all of the pending_stack_adjust
2495 to get this space. */
2497 = (combine_pending_stack_adjustment_and_call
2498 (unadjusted_args_size,
2499 &adjusted_args_size,
2500 preferred_unit_stack_boundary));
2502 /* combine_pending_stack_adjustment_and_call computes
2503 an adjustment before the arguments are allocated.
2504 Account for them and see whether or not the stack
2505 needs to go up or down. */
2506 needed = unadjusted_args_size - needed;
2510 /* We're releasing stack space. */
2511 /* ??? We can avoid any adjustment at all if we're
2512 already aligned. FIXME. */
2513 pending_stack_adjust = -needed;
2514 do_pending_stack_adjust ();
2518 /* We need to allocate space. We'll do that in
2519 push_block below. */
2520 pending_stack_adjust = 0;
2523 /* Special case this because overhead of `push_block' in
2524 this case is non-trivial. */
2526 argblock = virtual_outgoing_args_rtx;
2529 argblock = push_block (GEN_INT (needed), 0, 0);
2530 #ifdef ARGS_GROW_DOWNWARD
2531 argblock = plus_constant (argblock, needed);
2535 /* We only really need to call `copy_to_reg' in the case
2536 where push insns are going to be used to pass ARGBLOCK
2537 to a function call in ARGS. In that case, the stack
2538 pointer changes value from the allocation point to the
2539 call point, and hence the value of
2540 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2541 as well always do it. */
2542 argblock = copy_to_reg (argblock);
2547 if (ACCUMULATE_OUTGOING_ARGS)
2549 /* The save/restore code in store_one_arg handles all
2550 cases except one: a constructor call (including a C
2551 function returning a BLKmode struct) to initialize
2553 if (stack_arg_under_construction)
2556 = GEN_INT (adjusted_args_size.constant
2557 + (OUTGOING_REG_PARM_STACK_SPACE ? 0
2558 : reg_parm_stack_space));
2559 if (old_stack_level == 0)
2561 emit_stack_save (SAVE_BLOCK, &old_stack_level,
2563 old_stack_pointer_delta = stack_pointer_delta;
2564 old_pending_adj = pending_stack_adjust;
2565 pending_stack_adjust = 0;
2566 /* stack_arg_under_construction says whether a stack
2567 arg is being constructed at the old stack level.
2568 Pushing the stack gets a clean outgoing argument
2570 old_stack_arg_under_construction
2571 = stack_arg_under_construction;
2572 stack_arg_under_construction = 0;
2573 /* Make a new map for the new argument list. */
2574 if (stack_usage_map_buf)
2575 free (stack_usage_map_buf);
2576 stack_usage_map_buf = XCNEWVEC (char, highest_outgoing_arg_in_use);
2577 stack_usage_map = stack_usage_map_buf;
2578 highest_outgoing_arg_in_use = 0;
2580 allocate_dynamic_stack_space (push_size, NULL_RTX,
2584 /* If argument evaluation might modify the stack pointer,
2585 copy the address of the argument list to a register. */
2586 for (i = 0; i < num_actuals; i++)
2587 if (args[i].pass_on_stack)
2589 argblock = copy_addr_to_reg (argblock);
2594 compute_argument_addresses (args, argblock, num_actuals);
2596 /* If we push args individually in reverse order, perform stack alignment
2597 before the first push (the last arg). */
2598 if (PUSH_ARGS_REVERSED && argblock == 0
2599 && adjusted_args_size.constant != unadjusted_args_size)
2601 /* When the stack adjustment is pending, we get better code
2602 by combining the adjustments. */
2603 if (pending_stack_adjust
2604 && ! (flags & ECF_LIBCALL_BLOCK)
2605 && ! inhibit_defer_pop)
2607 pending_stack_adjust
2608 = (combine_pending_stack_adjustment_and_call
2609 (unadjusted_args_size,
2610 &adjusted_args_size,
2611 preferred_unit_stack_boundary));
2612 do_pending_stack_adjust ();
2614 else if (argblock == 0)
2615 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2616 - unadjusted_args_size));
2618 /* Now that the stack is properly aligned, pops can't safely
2619 be deferred during the evaluation of the arguments. */
2622 funexp = rtx_for_function_call (fndecl, addr);
2624 /* Figure out the register where the value, if any, will come back. */
2626 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2627 && ! structure_value_addr)
2629 if (pcc_struct_value)
2630 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2631 fndecl, NULL, (pass == 0));
2633 valreg = hard_function_value (TREE_TYPE (exp), fndecl, fntype,
2636 /* If VALREG is a PARALLEL whose first member has a zero
2637 offset, use that. This is for targets such as m68k that
2638 return the same value in multiple places. */
2639 if (GET_CODE (valreg) == PARALLEL)
2641 rtx elem = XVECEXP (valreg, 0, 0);
2642 rtx where = XEXP (elem, 0);
2643 rtx offset = XEXP (elem, 1);
2644 if (offset == const0_rtx
2645 && GET_MODE (where) == GET_MODE (valreg))
2650 /* Precompute all register parameters. It isn't safe to compute anything
2651 once we have started filling any specific hard regs. */
2652 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2654 if (CALL_EXPR_STATIC_CHAIN (exp))
2655 static_chain_value = expand_normal (CALL_EXPR_STATIC_CHAIN (exp));
2657 static_chain_value = 0;
2659 #ifdef REG_PARM_STACK_SPACE
2660 /* Save the fixed argument area if it's part of the caller's frame and
2661 is clobbered by argument setup for this call. */
2662 if (ACCUMULATE_OUTGOING_ARGS && pass)
2663 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2664 &low_to_save, &high_to_save);
2667 /* Now store (and compute if necessary) all non-register parms.
2668 These come before register parms, since they can require block-moves,
2669 which could clobber the registers used for register parms.
2670 Parms which have partial registers are not stored here,
2671 but we do preallocate space here if they want that. */
2673 for (i = 0; i < num_actuals; i++)
2674 if (args[i].reg == 0 || args[i].pass_on_stack)
2676 rtx before_arg = get_last_insn ();
2678 if (store_one_arg (&args[i], argblock, flags,
2679 adjusted_args_size.var != 0,
2680 reg_parm_stack_space)
2682 && check_sibcall_argument_overlap (before_arg,
2684 sibcall_failure = 1;
2686 if (flags & ECF_CONST
2688 && args[i].value == args[i].stack)
2689 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
2690 gen_rtx_USE (VOIDmode,
2695 /* If we have a parm that is passed in registers but not in memory
2696 and whose alignment does not permit a direct copy into registers,
2697 make a group of pseudos that correspond to each register that we
2699 if (STRICT_ALIGNMENT)
2700 store_unaligned_arguments_into_pseudos (args, num_actuals);
2702 /* Now store any partially-in-registers parm.
2703 This is the last place a block-move can happen. */
2705 for (i = 0; i < num_actuals; i++)
2706 if (args[i].partial != 0 && ! args[i].pass_on_stack)
2708 rtx before_arg = get_last_insn ();
2710 if (store_one_arg (&args[i], argblock, flags,
2711 adjusted_args_size.var != 0,
2712 reg_parm_stack_space)
2714 && check_sibcall_argument_overlap (before_arg,
2716 sibcall_failure = 1;
2719 /* If we pushed args in forward order, perform stack alignment
2720 after pushing the last arg. */
2721 if (!PUSH_ARGS_REVERSED && argblock == 0)
2722 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2723 - unadjusted_args_size));
2725 /* If register arguments require space on the stack and stack space
2726 was not preallocated, allocate stack space here for arguments
2727 passed in registers. */
2728 if (OUTGOING_REG_PARM_STACK_SPACE && !ACCUMULATE_OUTGOING_ARGS
2729 && must_preallocate == 0 && reg_parm_stack_space > 0)
2730 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
2732 /* Pass the function the address in which to return a
2734 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
2736 structure_value_addr
2737 = convert_memory_address (Pmode, structure_value_addr);
2738 emit_move_insn (struct_value,
2740 force_operand (structure_value_addr,
2743 if (REG_P (struct_value))
2744 use_reg (&call_fusage, struct_value);
2747 after_args = get_last_insn ();
2748 funexp = prepare_call_address (funexp, static_chain_value,
2749 &call_fusage, reg_parm_seen, pass == 0);
2751 load_register_parameters (args, num_actuals, &call_fusage, flags,
2752 pass == 0, &sibcall_failure);
2754 /* Save a pointer to the last insn before the call, so that we can
2755 later safely search backwards to find the CALL_INSN. */
2756 before_call = get_last_insn ();
2758 /* Set up next argument register. For sibling calls on machines
2759 with register windows this should be the incoming register. */
2760 #ifdef FUNCTION_INCOMING_ARG
2762 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
2766 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
2769 /* All arguments and registers used for the call must be set up by
2772 /* Stack must be properly aligned now. */
2774 || !(stack_pointer_delta % preferred_unit_stack_boundary));
2776 /* Generate the actual call instruction. */
2777 emit_call_1 (funexp, exp, fndecl, funtype, unadjusted_args_size,
2778 adjusted_args_size.constant, struct_value_size,
2779 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
2780 flags, & args_so_far);
2782 /* If the call setup or the call itself overlaps with anything
2783 of the argument setup we probably clobbered our call address.
2784 In that case we can't do sibcalls. */
2786 && check_sibcall_argument_overlap (after_args, 0, 0))
2787 sibcall_failure = 1;
2789 /* If a non-BLKmode value is returned at the most significant end
2790 of a register, shift the register right by the appropriate amount
2791 and update VALREG accordingly. BLKmode values are handled by the
2792 group load/store machinery below. */
2793 if (!structure_value_addr
2794 && !pcc_struct_value
2795 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
2796 && targetm.calls.return_in_msb (TREE_TYPE (exp)))
2798 if (shift_return_value (TYPE_MODE (TREE_TYPE (exp)), false, valreg))
2799 sibcall_failure = 1;
2800 valreg = gen_rtx_REG (TYPE_MODE (TREE_TYPE (exp)), REGNO (valreg));
2803 /* If call is cse'able, make appropriate pair of reg-notes around it.
2804 Test valreg so we don't crash; may safely ignore `const'
2805 if return type is void. Disable for PARALLEL return values, because
2806 we have no way to move such values into a pseudo register. */
2807 if (pass && (flags & ECF_LIBCALL_BLOCK))
2811 bool failed = valreg == 0 || GET_CODE (valreg) == PARALLEL;
2813 insns = get_insns ();
2815 /* Expansion of block moves possibly introduced a loop that may
2816 not appear inside libcall block. */
2817 for (insn = insns; insn; insn = NEXT_INSN (insn))
2829 rtx temp = gen_reg_rtx (GET_MODE (valreg));
2831 /* Mark the return value as a pointer if needed. */
2832 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
2833 mark_reg_pointer (temp,
2834 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
2837 if (flag_unsafe_math_optimizations
2839 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
2840 && (DECL_FUNCTION_CODE (fndecl) == BUILT_IN_SQRT
2841 || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_SQRTF
2842 || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_SQRTL))
2843 note = gen_rtx_fmt_e (SQRT,
2845 args[0].initial_value);
2848 /* Construct an "equal form" for the value which
2849 mentions all the arguments in order as well as
2850 the function name. */
2851 for (i = 0; i < num_actuals; i++)
2852 note = gen_rtx_EXPR_LIST (VOIDmode,
2853 args[i].initial_value, note);
2854 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
2856 if (flags & ECF_PURE)
2857 note = gen_rtx_EXPR_LIST (VOIDmode,
2858 gen_rtx_USE (VOIDmode,
2859 gen_rtx_MEM (BLKmode,
2860 gen_rtx_SCRATCH (VOIDmode))),
2863 emit_libcall_block (insns, temp, valreg, note);
2868 else if (pass && (flags & ECF_MALLOC))
2870 rtx temp = gen_reg_rtx (GET_MODE (valreg));
2873 /* The return value from a malloc-like function is a pointer. */
2874 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
2875 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
2877 emit_move_insn (temp, valreg);
2879 /* The return value from a malloc-like function can not alias
2881 last = get_last_insn ();
2883 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
2885 /* Write out the sequence. */
2886 insns = get_insns ();
2892 /* For calls to `setjmp', etc., inform
2893 function.c:setjmp_warnings that it should complain if
2894 nonvolatile values are live. For functions that cannot
2895 return, inform flow that control does not fall through. */
2897 if ((flags & ECF_NORETURN) || pass == 0)
2899 /* The barrier must be emitted
2900 immediately after the CALL_INSN. Some ports emit more
2901 than just a CALL_INSN above, so we must search for it here. */
2903 rtx last = get_last_insn ();
2904 while (!CALL_P (last))
2906 last = PREV_INSN (last);
2907 /* There was no CALL_INSN? */
2908 gcc_assert (last != before_call);
2911 emit_barrier_after (last);
2913 /* Stack adjustments after a noreturn call are dead code.
2914 However when NO_DEFER_POP is in effect, we must preserve
2915 stack_pointer_delta. */
2916 if (inhibit_defer_pop == 0)
2918 stack_pointer_delta = old_stack_allocated;
2919 pending_stack_adjust = 0;
2923 /* If value type not void, return an rtx for the value. */
2925 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
2927 target = const0_rtx;
2928 else if (structure_value_addr)
2930 if (target == 0 || !MEM_P (target))
2933 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
2934 memory_address (TYPE_MODE (TREE_TYPE (exp)),
2935 structure_value_addr));
2936 set_mem_attributes (target, exp, 1);
2939 else if (pcc_struct_value)
2941 /* This is the special C++ case where we need to
2942 know what the true target was. We take care to
2943 never use this value more than once in one expression. */
2944 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
2945 copy_to_reg (valreg));
2946 set_mem_attributes (target, exp, 1);
2948 /* Handle calls that return values in multiple non-contiguous locations.
2949 The Irix 6 ABI has examples of this. */
2950 else if (GET_CODE (valreg) == PARALLEL)
2954 /* This will only be assigned once, so it can be readonly. */
2955 tree nt = build_qualified_type (TREE_TYPE (exp),
2956 (TYPE_QUALS (TREE_TYPE (exp))
2957 | TYPE_QUAL_CONST));
2959 target = assign_temp (nt, 0, 1, 1);
2962 if (! rtx_equal_p (target, valreg))
2963 emit_group_store (target, valreg, TREE_TYPE (exp),
2964 int_size_in_bytes (TREE_TYPE (exp)));
2966 /* We can not support sibling calls for this case. */
2967 sibcall_failure = 1;
2970 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
2971 && GET_MODE (target) == GET_MODE (valreg))
2973 bool may_overlap = false;
2975 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
2976 reg to a plain register. */
2977 if (!REG_P (target) || HARD_REGISTER_P (target))
2978 valreg = avoid_likely_spilled_reg (valreg);
2980 /* If TARGET is a MEM in the argument area, and we have
2981 saved part of the argument area, then we can't store
2982 directly into TARGET as it may get overwritten when we
2983 restore the argument save area below. Don't work too
2984 hard though and simply force TARGET to a register if it
2985 is a MEM; the optimizer is quite likely to sort it out. */
2986 if (ACCUMULATE_OUTGOING_ARGS && pass && MEM_P (target))
2987 for (i = 0; i < num_actuals; i++)
2988 if (args[i].save_area)
2995 target = copy_to_reg (valreg);
2998 /* TARGET and VALREG cannot be equal at this point
2999 because the latter would not have
3000 REG_FUNCTION_VALUE_P true, while the former would if
3001 it were referring to the same register.
3003 If they refer to the same register, this move will be
3004 a no-op, except when function inlining is being
3006 emit_move_insn (target, valreg);
3008 /* If we are setting a MEM, this code must be executed.
3009 Since it is emitted after the call insn, sibcall
3010 optimization cannot be performed in that case. */
3012 sibcall_failure = 1;
3015 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3017 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3019 /* We can not support sibling calls for this case. */
3020 sibcall_failure = 1;
3023 target = copy_to_reg (avoid_likely_spilled_reg (valreg));
3025 if (targetm.calls.promote_function_return(funtype))
3027 /* If we promoted this return value, make the proper SUBREG.
3028 TARGET might be const0_rtx here, so be careful. */
3030 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3031 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3033 tree type = TREE_TYPE (exp);
3034 int unsignedp = TYPE_UNSIGNED (type);
3036 enum machine_mode pmode;
3038 pmode = promote_mode (type, TYPE_MODE (type), &unsignedp, 1);
3039 /* If we don't promote as expected, something is wrong. */
3040 gcc_assert (GET_MODE (target) == pmode);
3042 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3043 && (GET_MODE_SIZE (GET_MODE (target))
3044 > GET_MODE_SIZE (TYPE_MODE (type))))
3046 offset = GET_MODE_SIZE (GET_MODE (target))
3047 - GET_MODE_SIZE (TYPE_MODE (type));
3048 if (! BYTES_BIG_ENDIAN)
3049 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3050 else if (! WORDS_BIG_ENDIAN)
3051 offset %= UNITS_PER_WORD;
3053 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3054 SUBREG_PROMOTED_VAR_P (target) = 1;
3055 SUBREG_PROMOTED_UNSIGNED_SET (target, unsignedp);
3059 /* If size of args is variable or this was a constructor call for a stack
3060 argument, restore saved stack-pointer value. */
3062 if (old_stack_level)
3064 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3065 stack_pointer_delta = old_stack_pointer_delta;
3066 pending_stack_adjust = old_pending_adj;
3067 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
3068 stack_arg_under_construction = old_stack_arg_under_construction;
3069 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3070 stack_usage_map = initial_stack_usage_map;
3071 sibcall_failure = 1;
3073 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3075 #ifdef REG_PARM_STACK_SPACE
3077 restore_fixed_argument_area (save_area, argblock,
3078 high_to_save, low_to_save);
3081 /* If we saved any argument areas, restore them. */
3082 for (i = 0; i < num_actuals; i++)
3083 if (args[i].save_area)
3085 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3087 = gen_rtx_MEM (save_mode,
3088 memory_address (save_mode,
3089 XEXP (args[i].stack_slot, 0)));
3091 if (save_mode != BLKmode)
3092 emit_move_insn (stack_area, args[i].save_area);
3094 emit_block_move (stack_area, args[i].save_area,
3095 GEN_INT (args[i].locate.size.constant),
3096 BLOCK_OP_CALL_PARM);
3099 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3100 stack_usage_map = initial_stack_usage_map;
3103 /* If this was alloca, record the new stack level for nonlocal gotos.
3104 Check for the handler slots since we might not have a save area
3105 for non-local gotos. */
3107 if ((flags & ECF_MAY_BE_ALLOCA) && cfun->nonlocal_goto_save_area != 0)
3108 update_nonlocal_goto_save_area ();
3110 /* Free up storage we no longer need. */
3111 for (i = 0; i < num_actuals; ++i)
3112 if (args[i].aligned_regs)
3113 free (args[i].aligned_regs);
3115 insns = get_insns ();
3120 tail_call_insns = insns;
3122 /* Restore the pending stack adjustment now that we have
3123 finished generating the sibling call sequence. */
3125 pending_stack_adjust = save_pending_stack_adjust;
3126 stack_pointer_delta = save_stack_pointer_delta;
3128 /* Prepare arg structure for next iteration. */
3129 for (i = 0; i < num_actuals; i++)
3132 args[i].aligned_regs = 0;
3136 sbitmap_free (stored_args_map);
3140 normal_call_insns = insns;
3142 /* Verify that we've deallocated all the stack we used. */
3143 gcc_assert ((flags & ECF_NORETURN)
3144 || (old_stack_allocated
3145 == stack_pointer_delta - pending_stack_adjust));
3148 /* If something prevents making this a sibling call,
3149 zero out the sequence. */
3150 if (sibcall_failure)
3151 tail_call_insns = NULL_RTX;
3156 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
3157 arguments too, as argument area is now clobbered by the call. */
3158 if (tail_call_insns)
3160 emit_insn (tail_call_insns);
3161 crtl->tail_call_emit = true;
3164 emit_insn (normal_call_insns);
3166 currently_expanding_call--;
3168 if (stack_usage_map_buf)
3169 free (stack_usage_map_buf);
3174 /* A sibling call sequence invalidates any REG_EQUIV notes made for
3175 this function's incoming arguments.
3177 At the start of RTL generation we know the only REG_EQUIV notes
3178 in the rtl chain are those for incoming arguments, so we can look
3179 for REG_EQUIV notes between the start of the function and the
3180 NOTE_INSN_FUNCTION_BEG.
3182 This is (slight) overkill. We could keep track of the highest
3183 argument we clobber and be more selective in removing notes, but it
3184 does not seem to be worth the effort. */
3187 fixup_tail_calls (void)
3191 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3195 /* There are never REG_EQUIV notes for the incoming arguments
3196 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
3198 && NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG)
3201 note = find_reg_note (insn, REG_EQUIV, 0);
3203 remove_note (insn, note);
3204 note = find_reg_note (insn, REG_EQUIV, 0);
3209 /* Traverse a list of TYPES and expand all complex types into their
3212 split_complex_types (tree types)
3216 /* Before allocating memory, check for the common case of no complex. */
3217 for (p = types; p; p = TREE_CHAIN (p))
3219 tree type = TREE_VALUE (p);
3220 if (TREE_CODE (type) == COMPLEX_TYPE
3221 && targetm.calls.split_complex_arg (type))
3227 types = copy_list (types);
3229 for (p = types; p; p = TREE_CHAIN (p))
3231 tree complex_type = TREE_VALUE (p);
3233 if (TREE_CODE (complex_type) == COMPLEX_TYPE
3234 && targetm.calls.split_complex_arg (complex_type))
3238 /* Rewrite complex type with component type. */
3239 TREE_VALUE (p) = TREE_TYPE (complex_type);
3240 next = TREE_CHAIN (p);
3242 /* Add another component type for the imaginary part. */
3243 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
3244 TREE_CHAIN (p) = imag;
3245 TREE_CHAIN (imag) = next;
3247 /* Skip the newly created node. */
3255 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3256 The RETVAL parameter specifies whether return value needs to be saved, other
3257 parameters are documented in the emit_library_call function below. */
3260 emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
3261 enum libcall_type fn_type,
3262 enum machine_mode outmode, int nargs, va_list p)
3264 /* Total size in bytes of all the stack-parms scanned so far. */
3265 struct args_size args_size;
3266 /* Size of arguments before any adjustments (such as rounding). */
3267 struct args_size original_args_size;
3273 CUMULATIVE_ARGS args_so_far;
3277 enum machine_mode mode;
3280 struct locate_and_pad_arg_data locate;
3284 int old_inhibit_defer_pop = inhibit_defer_pop;
3285 rtx call_fusage = 0;
3288 int pcc_struct_value = 0;
3289 int struct_value_size = 0;
3291 int reg_parm_stack_space = 0;
3294 tree tfom; /* type_for_mode (outmode, 0) */
3296 #ifdef REG_PARM_STACK_SPACE
3297 /* Define the boundary of the register parm stack space that needs to be
3299 int low_to_save, high_to_save;
3300 rtx save_area = 0; /* Place that it is saved. */
3303 /* Size of the stack reserved for parameter registers. */
3304 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3305 char *initial_stack_usage_map = stack_usage_map;
3306 char *stack_usage_map_buf = NULL;
3308 rtx struct_value = targetm.calls.struct_value_rtx (0, 0);
3310 #ifdef REG_PARM_STACK_SPACE
3311 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3314 /* By default, library functions can not throw. */
3315 flags = ECF_NOTHROW;
3327 case LCT_CONST_MAKE_BLOCK:
3328 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
3330 case LCT_PURE_MAKE_BLOCK:
3331 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
3334 flags |= ECF_NORETURN;
3337 flags = ECF_NORETURN;
3339 case LCT_RETURNS_TWICE:
3340 flags = ECF_RETURNS_TWICE;
3345 /* Ensure current function's preferred stack boundary is at least
3347 if (crtl->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3348 crtl->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3350 /* If this kind of value comes back in memory,
3351 decide where in memory it should come back. */
3352 if (outmode != VOIDmode)
3354 tfom = lang_hooks.types.type_for_mode (outmode, 0);
3355 if (aggregate_value_p (tfom, 0))
3357 #ifdef PCC_STATIC_STRUCT_RETURN
3359 = hard_function_value (build_pointer_type (tfom), 0, 0, 0);
3360 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3361 pcc_struct_value = 1;
3363 value = gen_reg_rtx (outmode);
3364 #else /* not PCC_STATIC_STRUCT_RETURN */
3365 struct_value_size = GET_MODE_SIZE (outmode);
3366 if (value != 0 && MEM_P (value))
3369 mem_value = assign_temp (tfom, 0, 1, 1);
3371 /* This call returns a big structure. */
3372 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3376 tfom = void_type_node;
3378 /* ??? Unfinished: must pass the memory address as an argument. */
3380 /* Copy all the libcall-arguments out of the varargs data
3381 and into a vector ARGVEC.
3383 Compute how to pass each argument. We only support a very small subset
3384 of the full argument passing conventions to limit complexity here since
3385 library functions shouldn't have many args. */
3387 argvec = alloca ((nargs + 1) * sizeof (struct arg));
3388 memset (argvec, 0, (nargs + 1) * sizeof (struct arg));
3390 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3391 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far, outmode, fun);
3393 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0, nargs);
3396 args_size.constant = 0;
3401 /* Now we are about to start emitting insns that can be deleted
3402 if a libcall is deleted. */
3403 if (flags & ECF_LIBCALL_BLOCK)
3408 /* If there's a structure value address to be passed,
3409 either pass it in the special place, or pass it as an extra argument. */
3410 if (mem_value && struct_value == 0 && ! pcc_struct_value)
3412 rtx addr = XEXP (mem_value, 0);
3416 /* Make sure it is a reasonable operand for a move or push insn. */
3417 if (!REG_P (addr) && !MEM_P (addr)
3418 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3419 addr = force_operand (addr, NULL_RTX);
3421 argvec[count].value = addr;
3422 argvec[count].mode = Pmode;
3423 argvec[count].partial = 0;
3425 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3426 gcc_assert (targetm.calls.arg_partial_bytes (&args_so_far, Pmode,
3427 NULL_TREE, 1) == 0);
3429 locate_and_pad_parm (Pmode, NULL_TREE,
3430 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3433 argvec[count].reg != 0,
3435 0, NULL_TREE, &args_size, &argvec[count].locate);
3437 if (argvec[count].reg == 0 || argvec[count].partial != 0
3438 || reg_parm_stack_space > 0)
3439 args_size.constant += argvec[count].locate.size.constant;
3441 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3446 for (; count < nargs; count++)
3448 rtx val = va_arg (p, rtx);
3449 enum machine_mode mode = va_arg (p, enum machine_mode);
3451 /* We cannot convert the arg value to the mode the library wants here;
3452 must do it earlier where we know the signedness of the arg. */
3453 gcc_assert (mode != BLKmode
3454 && (GET_MODE (val) == mode || GET_MODE (val) == VOIDmode));
3456 /* Make sure it is a reasonable operand for a move or push insn. */
3457 if (!REG_P (val) && !MEM_P (val)
3458 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3459 val = force_operand (val, NULL_RTX);
3461 if (pass_by_reference (&args_so_far, mode, NULL_TREE, 1))
3465 = !reference_callee_copied (&args_so_far, mode, NULL_TREE, 1);
3467 /* loop.c won't look at CALL_INSN_FUNCTION_USAGE of const/pure
3468 functions, so we have to pretend this isn't such a function. */
3469 if (flags & ECF_LIBCALL_BLOCK)
3471 rtx insns = get_insns ();
3475 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3477 /* If this was a CONST function, it is now PURE since
3478 it now reads memory. */
3479 if (flags & ECF_CONST)
3481 flags &= ~ECF_CONST;
3485 if (GET_MODE (val) == MEM && !must_copy)
3489 slot = assign_temp (lang_hooks.types.type_for_mode (mode, 0),
3491 emit_move_insn (slot, val);
3494 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3495 gen_rtx_USE (VOIDmode, slot),
3498 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3499 gen_rtx_CLOBBER (VOIDmode,
3504 val = force_operand (XEXP (slot, 0), NULL_RTX);
3507 argvec[count].value = val;
3508 argvec[count].mode = mode;
3510 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3512 argvec[count].partial
3513 = targetm.calls.arg_partial_bytes (&args_so_far, mode, NULL_TREE, 1);
3515 locate_and_pad_parm (mode, NULL_TREE,
3516 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3519 argvec[count].reg != 0,
3521 argvec[count].partial,
3522 NULL_TREE, &args_size, &argvec[count].locate);
3524 gcc_assert (!argvec[count].locate.size.var);
3526 if (argvec[count].reg == 0 || argvec[count].partial != 0
3527 || reg_parm_stack_space > 0)
3528 args_size.constant += argvec[count].locate.size.constant;
3530 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3533 /* If this machine requires an external definition for library
3534 functions, write one out. */
3535 assemble_external_libcall (fun);
3537 original_args_size = args_size;
3538 args_size.constant = (((args_size.constant
3539 + stack_pointer_delta
3543 - stack_pointer_delta);
3545 args_size.constant = MAX (args_size.constant,
3546 reg_parm_stack_space);
3548 if (!OUTGOING_REG_PARM_STACK_SPACE)
3549 args_size.constant -= reg_parm_stack_space;
3551 if (args_size.constant > crtl->outgoing_args_size)
3552 crtl->outgoing_args_size = args_size.constant;
3554 if (ACCUMULATE_OUTGOING_ARGS)
3556 /* Since the stack pointer will never be pushed, it is possible for
3557 the evaluation of a parm to clobber something we have already
3558 written to the stack. Since most function calls on RISC machines
3559 do not use the stack, this is uncommon, but must work correctly.
3561 Therefore, we save any area of the stack that was already written
3562 and that we are using. Here we set up to do this by making a new
3563 stack usage map from the old one.
3565 Another approach might be to try to reorder the argument
3566 evaluations to avoid this conflicting stack usage. */
3568 needed = args_size.constant;
3570 /* Since we will be writing into the entire argument area, the
3571 map must be allocated for its entire size, not just the part that
3572 is the responsibility of the caller. */
3573 if (!OUTGOING_REG_PARM_STACK_SPACE)
3574 needed += reg_parm_stack_space;
3576 #ifdef ARGS_GROW_DOWNWARD
3577 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3580 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3583 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
3584 stack_usage_map = stack_usage_map_buf;
3586 if (initial_highest_arg_in_use)
3587 memcpy (stack_usage_map, initial_stack_usage_map,
3588 initial_highest_arg_in_use);
3590 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3591 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3592 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3595 /* We must be careful to use virtual regs before they're instantiated,
3596 and real regs afterwards. Loop optimization, for example, can create
3597 new libcalls after we've instantiated the virtual regs, and if we
3598 use virtuals anyway, they won't match the rtl patterns. */
3600 if (virtuals_instantiated)
3601 argblock = plus_constant (stack_pointer_rtx, STACK_POINTER_OFFSET);
3603 argblock = virtual_outgoing_args_rtx;
3608 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3611 /* If we push args individually in reverse order, perform stack alignment
3612 before the first push (the last arg). */
3613 if (argblock == 0 && PUSH_ARGS_REVERSED)
3614 anti_adjust_stack (GEN_INT (args_size.constant
3615 - original_args_size.constant));
3617 if (PUSH_ARGS_REVERSED)
3628 #ifdef REG_PARM_STACK_SPACE
3629 if (ACCUMULATE_OUTGOING_ARGS)
3631 /* The argument list is the property of the called routine and it
3632 may clobber it. If the fixed area has been used for previous
3633 parameters, we must save and restore it. */
3634 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3635 &low_to_save, &high_to_save);
3639 /* Push the args that need to be pushed. */
3641 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3642 are to be pushed. */
3643 for (count = 0; count < nargs; count++, argnum += inc)
3645 enum machine_mode mode = argvec[argnum].mode;
3646 rtx val = argvec[argnum].value;
3647 rtx reg = argvec[argnum].reg;
3648 int partial = argvec[argnum].partial;
3649 int lower_bound = 0, upper_bound = 0, i;
3651 if (! (reg != 0 && partial == 0))
3653 if (ACCUMULATE_OUTGOING_ARGS)
3655 /* If this is being stored into a pre-allocated, fixed-size,
3656 stack area, save any previous data at that location. */
3658 #ifdef ARGS_GROW_DOWNWARD
3659 /* stack_slot is negative, but we want to index stack_usage_map
3660 with positive values. */
3661 upper_bound = -argvec[argnum].locate.offset.constant + 1;
3662 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
3664 lower_bound = argvec[argnum].locate.offset.constant;
3665 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
3669 /* Don't worry about things in the fixed argument area;
3670 it has already been saved. */
3671 if (i < reg_parm_stack_space)
3672 i = reg_parm_stack_space;
3673 while (i < upper_bound && stack_usage_map[i] == 0)
3676 if (i < upper_bound)
3678 /* We need to make a save area. */
3680 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
3681 enum machine_mode save_mode
3682 = mode_for_size (size, MODE_INT, 1);
3684 = plus_constant (argblock,
3685 argvec[argnum].locate.offset.constant);
3687 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
3689 if (save_mode == BLKmode)
3691 argvec[argnum].save_area
3692 = assign_stack_temp (BLKmode,
3693 argvec[argnum].locate.size.constant,
3696 emit_block_move (validize_mem (argvec[argnum].save_area),
3698 GEN_INT (argvec[argnum].locate.size.constant),
3699 BLOCK_OP_CALL_PARM);
3703 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3705 emit_move_insn (argvec[argnum].save_area, stack_area);
3710 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, PARM_BOUNDARY,
3711 partial, reg, 0, argblock,
3712 GEN_INT (argvec[argnum].locate.offset.constant),
3713 reg_parm_stack_space,
3714 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad));
3716 /* Now mark the segment we just used. */
3717 if (ACCUMULATE_OUTGOING_ARGS)
3718 for (i = lower_bound; i < upper_bound; i++)
3719 stack_usage_map[i] = 1;
3723 if (flags & ECF_CONST)
3727 /* Indicate argument access so that alias.c knows that these
3730 use = plus_constant (argblock,
3731 argvec[argnum].locate.offset.constant);
3733 /* When arguments are pushed, trying to tell alias.c where
3734 exactly this argument is won't work, because the
3735 auto-increment causes confusion. So we merely indicate
3736 that we access something with a known mode somewhere on
3738 use = gen_rtx_PLUS (Pmode, virtual_outgoing_args_rtx,
3739 gen_rtx_SCRATCH (Pmode));
3740 use = gen_rtx_MEM (argvec[argnum].mode, use);
3741 use = gen_rtx_USE (VOIDmode, use);
3742 call_fusage = gen_rtx_EXPR_LIST (VOIDmode, use, call_fusage);
3747 /* If we pushed args in forward order, perform stack alignment
3748 after pushing the last arg. */
3749 if (argblock == 0 && !PUSH_ARGS_REVERSED)
3750 anti_adjust_stack (GEN_INT (args_size.constant
3751 - original_args_size.constant));
3753 if (PUSH_ARGS_REVERSED)
3758 fun = prepare_call_address (fun, NULL, &call_fusage, 0, 0);
3760 /* Now load any reg parms into their regs. */
3762 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3763 are to be pushed. */
3764 for (count = 0; count < nargs; count++, argnum += inc)
3766 enum machine_mode mode = argvec[argnum].mode;
3767 rtx val = argvec[argnum].value;
3768 rtx reg = argvec[argnum].reg;
3769 int partial = argvec[argnum].partial;
3771 /* Handle calls that pass values in multiple non-contiguous
3772 locations. The PA64 has examples of this for library calls. */
3773 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3774 emit_group_load (reg, val, NULL_TREE, GET_MODE_SIZE (mode));
3775 else if (reg != 0 && partial == 0)
3776 emit_move_insn (reg, val);
3781 /* Any regs containing parms remain in use through the call. */
3782 for (count = 0; count < nargs; count++)
3784 rtx reg = argvec[count].reg;
3785 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3786 use_group_regs (&call_fusage, reg);
3789 int partial = argvec[count].partial;
3793 gcc_assert (partial % UNITS_PER_WORD == 0);
3794 nregs = partial / UNITS_PER_WORD;
3795 use_regs (&call_fusage, REGNO (reg), nregs);
3798 use_reg (&call_fusage, reg);
3802 /* Pass the function the address in which to return a structure value. */
3803 if (mem_value != 0 && struct_value != 0 && ! pcc_struct_value)
3805 emit_move_insn (struct_value,
3807 force_operand (XEXP (mem_value, 0),
3809 if (REG_P (struct_value))
3810 use_reg (&call_fusage, struct_value);
3813 /* Don't allow popping to be deferred, since then
3814 cse'ing of library calls could delete a call and leave the pop. */
3816 valreg = (mem_value == 0 && outmode != VOIDmode
3817 ? hard_libcall_value (outmode) : NULL_RTX);
3819 /* Stack must be properly aligned now. */
3820 gcc_assert (!(stack_pointer_delta
3821 & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1)));
3823 before_call = get_last_insn ();
3825 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
3826 will set inhibit_defer_pop to that value. */
3827 /* The return type is needed to decide how many bytes the function pops.
3828 Signedness plays no role in that, so for simplicity, we pretend it's
3829 always signed. We also assume that the list of arguments passed has
3830 no impact, so we pretend it is unknown. */
3832 emit_call_1 (fun, NULL,
3833 get_identifier (XSTR (orgfun, 0)),
3834 build_function_type (tfom, NULL_TREE),
3835 original_args_size.constant, args_size.constant,
3837 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
3839 old_inhibit_defer_pop + 1, call_fusage, flags, & args_so_far);
3841 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
3842 that it should complain if nonvolatile values are live. For
3843 functions that cannot return, inform flow that control does not
3846 if (flags & ECF_NORETURN)
3848 /* The barrier note must be emitted
3849 immediately after the CALL_INSN. Some ports emit more than
3850 just a CALL_INSN above, so we must search for it here. */
3852 rtx last = get_last_insn ();
3853 while (!CALL_P (last))
3855 last = PREV_INSN (last);
3856 /* There was no CALL_INSN? */
3857 gcc_assert (last != before_call);
3860 emit_barrier_after (last);
3863 /* Now restore inhibit_defer_pop to its actual original value. */
3866 /* If call is cse'able, make appropriate pair of reg-notes around it.
3867 Test valreg so we don't crash; may safely ignore `const'
3868 if return type is void. Disable for PARALLEL return values, because
3869 we have no way to move such values into a pseudo register. */
3870 if (flags & ECF_LIBCALL_BLOCK)
3876 insns = get_insns ();
3886 if (GET_CODE (valreg) == PARALLEL)
3888 temp = gen_reg_rtx (outmode);
3889 emit_group_store (temp, valreg, NULL_TREE,
3890 GET_MODE_SIZE (outmode));
3894 temp = gen_reg_rtx (GET_MODE (valreg));
3896 /* Construct an "equal form" for the value which mentions all the
3897 arguments in order as well as the function name. */
3898 for (i = 0; i < nargs; i++)
3899 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
3900 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
3902 insns = get_insns ();
3905 if (flags & ECF_PURE)
3906 note = gen_rtx_EXPR_LIST (VOIDmode,
3907 gen_rtx_USE (VOIDmode,
3908 gen_rtx_MEM (BLKmode,
3909 gen_rtx_SCRATCH (VOIDmode))),
3912 emit_libcall_block (insns, temp, valreg, note);
3919 /* Copy the value to the right place. */
3920 if (outmode != VOIDmode && retval)
3926 if (value != mem_value)
3927 emit_move_insn (value, mem_value);
3929 else if (GET_CODE (valreg) == PARALLEL)
3932 value = gen_reg_rtx (outmode);
3933 emit_group_store (value, valreg, NULL_TREE, GET_MODE_SIZE (outmode));
3937 /* Convert to the proper mode if PROMOTE_MODE has been active. */
3938 if (GET_MODE (valreg) != outmode)
3940 int unsignedp = TYPE_UNSIGNED (tfom);
3942 gcc_assert (targetm.calls.promote_function_return (tfom));
3943 gcc_assert (promote_mode (tfom, outmode, &unsignedp, 0)
3944 == GET_MODE (valreg));
3946 valreg = convert_modes (outmode, GET_MODE (valreg), valreg, 0);
3950 emit_move_insn (value, valreg);
3956 if (ACCUMULATE_OUTGOING_ARGS)
3958 #ifdef REG_PARM_STACK_SPACE
3960 restore_fixed_argument_area (save_area, argblock,
3961 high_to_save, low_to_save);
3964 /* If we saved any argument areas, restore them. */
3965 for (count = 0; count < nargs; count++)
3966 if (argvec[count].save_area)
3968 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
3969 rtx adr = plus_constant (argblock,
3970 argvec[count].locate.offset.constant);
3971 rtx stack_area = gen_rtx_MEM (save_mode,
3972 memory_address (save_mode, adr));
3974 if (save_mode == BLKmode)
3975 emit_block_move (stack_area,
3976 validize_mem (argvec[count].save_area),
3977 GEN_INT (argvec[count].locate.size.constant),
3978 BLOCK_OP_CALL_PARM);
3980 emit_move_insn (stack_area, argvec[count].save_area);
3983 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3984 stack_usage_map = initial_stack_usage_map;
3987 if (stack_usage_map_buf)
3988 free (stack_usage_map_buf);
3994 /* Output a library call to function FUN (a SYMBOL_REF rtx)
3995 (emitting the queue unless NO_QUEUE is nonzero),
3996 for a value of mode OUTMODE,
3997 with NARGS different arguments, passed as alternating rtx values
3998 and machine_modes to convert them to.
4000 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4001 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4002 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4003 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4004 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4005 or other LCT_ value for other types of library calls. */
4008 emit_library_call (rtx orgfun, enum libcall_type fn_type,
4009 enum machine_mode outmode, int nargs, ...)
4013 va_start (p, nargs);
4014 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4018 /* Like emit_library_call except that an extra argument, VALUE,
4019 comes second and says where to store the result.
4020 (If VALUE is zero, this function chooses a convenient way
4021 to return the value.
4023 This function returns an rtx for where the value is to be found.
4024 If VALUE is nonzero, VALUE is returned. */
4027 emit_library_call_value (rtx orgfun, rtx value,
4028 enum libcall_type fn_type,
4029 enum machine_mode outmode, int nargs, ...)
4034 va_start (p, nargs);
4035 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4042 /* Store a single argument for a function call
4043 into the register or memory area where it must be passed.
4044 *ARG describes the argument value and where to pass it.
4046 ARGBLOCK is the address of the stack-block for all the arguments,
4047 or 0 on a machine where arguments are pushed individually.
4049 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4050 so must be careful about how the stack is used.
4052 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4053 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4054 that we need not worry about saving and restoring the stack.
4056 FNDECL is the declaration of the function we are calling.
4058 Return nonzero if this arg should cause sibcall failure,
4062 store_one_arg (struct arg_data *arg, rtx argblock, int flags,
4063 int variable_size ATTRIBUTE_UNUSED, int reg_parm_stack_space)
4065 tree pval = arg->tree_value;
4069 int i, lower_bound = 0, upper_bound = 0;
4070 int sibcall_failure = 0;
4072 if (TREE_CODE (pval) == ERROR_MARK)
4075 /* Push a new temporary level for any temporaries we make for
4079 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4081 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4082 save any previous data at that location. */
4083 if (argblock && ! variable_size && arg->stack)
4085 #ifdef ARGS_GROW_DOWNWARD
4086 /* stack_slot is negative, but we want to index stack_usage_map
4087 with positive values. */
4088 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4089 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4093 lower_bound = upper_bound - arg->locate.size.constant;
4095 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4096 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4100 upper_bound = lower_bound + arg->locate.size.constant;
4104 /* Don't worry about things in the fixed argument area;
4105 it has already been saved. */
4106 if (i < reg_parm_stack_space)
4107 i = reg_parm_stack_space;
4108 while (i < upper_bound && stack_usage_map[i] == 0)
4111 if (i < upper_bound)
4113 /* We need to make a save area. */
4114 unsigned int size = arg->locate.size.constant * BITS_PER_UNIT;
4115 enum machine_mode save_mode = mode_for_size (size, MODE_INT, 1);
4116 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
4117 rtx stack_area = gen_rtx_MEM (save_mode, adr);
4119 if (save_mode == BLKmode)
4121 tree ot = TREE_TYPE (arg->tree_value);
4122 tree nt = build_qualified_type (ot, (TYPE_QUALS (ot)
4123 | TYPE_QUAL_CONST));
4125 arg->save_area = assign_temp (nt, 0, 1, 1);
4126 preserve_temp_slots (arg->save_area);
4127 emit_block_move (validize_mem (arg->save_area), stack_area,
4128 GEN_INT (arg->locate.size.constant),
4129 BLOCK_OP_CALL_PARM);
4133 arg->save_area = gen_reg_rtx (save_mode);
4134 emit_move_insn (arg->save_area, stack_area);
4140 /* If this isn't going to be placed on both the stack and in registers,
4141 set up the register and number of words. */
4142 if (! arg->pass_on_stack)
4144 if (flags & ECF_SIBCALL)
4145 reg = arg->tail_call_reg;
4148 partial = arg->partial;
4151 /* Being passed entirely in a register. We shouldn't be called in
4153 gcc_assert (reg == 0 || partial != 0);
4155 /* If this arg needs special alignment, don't load the registers
4157 if (arg->n_aligned_regs != 0)
4160 /* If this is being passed partially in a register, we can't evaluate
4161 it directly into its stack slot. Otherwise, we can. */
4162 if (arg->value == 0)
4164 /* stack_arg_under_construction is nonzero if a function argument is
4165 being evaluated directly into the outgoing argument list and
4166 expand_call must take special action to preserve the argument list
4167 if it is called recursively.
4169 For scalar function arguments stack_usage_map is sufficient to
4170 determine which stack slots must be saved and restored. Scalar
4171 arguments in general have pass_on_stack == 0.
4173 If this argument is initialized by a function which takes the
4174 address of the argument (a C++ constructor or a C function
4175 returning a BLKmode structure), then stack_usage_map is
4176 insufficient and expand_call must push the stack around the
4177 function call. Such arguments have pass_on_stack == 1.
4179 Note that it is always safe to set stack_arg_under_construction,
4180 but this generates suboptimal code if set when not needed. */
4182 if (arg->pass_on_stack)
4183 stack_arg_under_construction++;
4185 arg->value = expand_expr (pval,
4187 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4188 ? NULL_RTX : arg->stack,
4189 VOIDmode, EXPAND_STACK_PARM);
4191 /* If we are promoting object (or for any other reason) the mode
4192 doesn't agree, convert the mode. */
4194 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4195 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4196 arg->value, arg->unsignedp);
4198 if (arg->pass_on_stack)
4199 stack_arg_under_construction--;
4202 /* Check for overlap with already clobbered argument area. */
4203 if ((flags & ECF_SIBCALL)
4204 && MEM_P (arg->value)
4205 && mem_overlaps_already_clobbered_arg_p (XEXP (arg->value, 0),
4206 arg->locate.size.constant))
4207 sibcall_failure = 1;
4209 /* Don't allow anything left on stack from computation
4210 of argument to alloca. */
4211 if (flags & ECF_MAY_BE_ALLOCA)
4212 do_pending_stack_adjust ();
4214 if (arg->value == arg->stack)
4215 /* If the value is already in the stack slot, we are done. */
4217 else if (arg->mode != BLKmode)
4220 unsigned int parm_align;
4222 /* Argument is a scalar, not entirely passed in registers.
4223 (If part is passed in registers, arg->partial says how much
4224 and emit_push_insn will take care of putting it there.)
4226 Push it, and if its size is less than the
4227 amount of space allocated to it,
4228 also bump stack pointer by the additional space.
4229 Note that in C the default argument promotions
4230 will prevent such mismatches. */
4232 size = GET_MODE_SIZE (arg->mode);
4233 /* Compute how much space the push instruction will push.
4234 On many machines, pushing a byte will advance the stack
4235 pointer by a halfword. */
4236 #ifdef PUSH_ROUNDING
4237 size = PUSH_ROUNDING (size);
4241 /* Compute how much space the argument should get:
4242 round up to a multiple of the alignment for arguments. */
4243 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4244 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4245 / (PARM_BOUNDARY / BITS_PER_UNIT))
4246 * (PARM_BOUNDARY / BITS_PER_UNIT));
4248 /* Compute the alignment of the pushed argument. */
4249 parm_align = arg->locate.boundary;
4250 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4252 int pad = used - size;
4255 unsigned int pad_align = (pad & -pad) * BITS_PER_UNIT;
4256 parm_align = MIN (parm_align, pad_align);
4260 /* This isn't already where we want it on the stack, so put it there.
4261 This can either be done with push or copy insns. */
4262 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
4263 parm_align, partial, reg, used - size, argblock,
4264 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4265 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4267 /* Unless this is a partially-in-register argument, the argument is now
4270 arg->value = arg->stack;
4274 /* BLKmode, at least partly to be pushed. */
4276 unsigned int parm_align;
4280 /* Pushing a nonscalar.
4281 If part is passed in registers, PARTIAL says how much
4282 and emit_push_insn will take care of putting it there. */
4284 /* Round its size up to a multiple
4285 of the allocation unit for arguments. */
4287 if (arg->locate.size.var != 0)
4290 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
4294 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
4295 for BLKmode is careful to avoid it. */
4296 excess = (arg->locate.size.constant
4297 - int_size_in_bytes (TREE_TYPE (pval))
4299 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
4300 NULL_RTX, TYPE_MODE (sizetype), 0);
4303 parm_align = arg->locate.boundary;
4305 /* When an argument is padded down, the block is aligned to
4306 PARM_BOUNDARY, but the actual argument isn't. */
4307 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4309 if (arg->locate.size.var)
4310 parm_align = BITS_PER_UNIT;
4313 unsigned int excess_align = (excess & -excess) * BITS_PER_UNIT;
4314 parm_align = MIN (parm_align, excess_align);
4318 if ((flags & ECF_SIBCALL) && MEM_P (arg->value))
4320 /* emit_push_insn might not work properly if arg->value and
4321 argblock + arg->locate.offset areas overlap. */
4325 if (XEXP (x, 0) == crtl->args.internal_arg_pointer
4326 || (GET_CODE (XEXP (x, 0)) == PLUS
4327 && XEXP (XEXP (x, 0), 0) ==
4328 crtl->args.internal_arg_pointer
4329 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT))
4331 if (XEXP (x, 0) != crtl->args.internal_arg_pointer)
4332 i = INTVAL (XEXP (XEXP (x, 0), 1));
4334 /* expand_call should ensure this. */
4335 gcc_assert (!arg->locate.offset.var
4336 && arg->locate.size.var == 0
4337 && GET_CODE (size_rtx) == CONST_INT);
4339 if (arg->locate.offset.constant > i)
4341 if (arg->locate.offset.constant < i + INTVAL (size_rtx))
4342 sibcall_failure = 1;
4344 else if (arg->locate.offset.constant < i)
4346 /* Use arg->locate.size.constant instead of size_rtx
4347 because we only care about the part of the argument
4349 if (i < (arg->locate.offset.constant
4350 + arg->locate.size.constant))
4351 sibcall_failure = 1;
4355 /* Even though they appear to be at the same location,
4356 if part of the outgoing argument is in registers,
4357 they aren't really at the same location. Check for
4358 this by making sure that the incoming size is the
4359 same as the outgoing size. */
4360 if (arg->locate.size.constant != INTVAL (size_rtx))
4361 sibcall_failure = 1;
4366 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4367 parm_align, partial, reg, excess, argblock,
4368 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4369 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4371 /* Unless this is a partially-in-register argument, the argument is now
4374 ??? Unlike the case above, in which we want the actual
4375 address of the data, so that we can load it directly into a
4376 register, here we want the address of the stack slot, so that
4377 it's properly aligned for word-by-word copying or something
4378 like that. It's not clear that this is always correct. */
4380 arg->value = arg->stack_slot;
4383 if (arg->reg && GET_CODE (arg->reg) == PARALLEL)
4385 tree type = TREE_TYPE (arg->tree_value);
4387 = emit_group_load_into_temps (arg->reg, arg->value, type,
4388 int_size_in_bytes (type));
4391 /* Mark all slots this store used. */
4392 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
4393 && argblock && ! variable_size && arg->stack)
4394 for (i = lower_bound; i < upper_bound; i++)
4395 stack_usage_map[i] = 1;
4397 /* Once we have pushed something, pops can't safely
4398 be deferred during the rest of the arguments. */
4401 /* Free any temporary slots made in processing this argument. Show
4402 that we might have taken the address of something and pushed that
4404 preserve_temp_slots (NULL_RTX);
4408 return sibcall_failure;
4411 /* Nonzero if we do not know how to pass TYPE solely in registers. */
4414 must_pass_in_stack_var_size (enum machine_mode mode ATTRIBUTE_UNUSED,
4420 /* If the type has variable size... */
4421 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4424 /* If the type is marked as addressable (it is required
4425 to be constructed into the stack)... */
4426 if (TREE_ADDRESSABLE (type))
4432 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
4433 takes trailing padding of a structure into account. */
4434 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
4437 must_pass_in_stack_var_size_or_pad (enum machine_mode mode, const_tree type)
4442 /* If the type has variable size... */
4443 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4446 /* If the type is marked as addressable (it is required
4447 to be constructed into the stack)... */
4448 if (TREE_ADDRESSABLE (type))
4451 /* If the padding and mode of the type is such that a copy into
4452 a register would put it into the wrong part of the register. */
4454 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
4455 && (FUNCTION_ARG_PADDING (mode, type)
4456 == (BYTES_BIG_ENDIAN ? upward : downward)))