* Makefile.in (options.c options.h): Use stamp file s-options to
[official-gcc.git] / gcc / calls.c
blobb4d66f9221286c725b0a7e0ebda8291c6d2c731e
1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
10 version.
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
20 02111-1307, USA. */
22 #include "config.h"
23 #include "system.h"
24 #include "coretypes.h"
25 #include "tm.h"
26 #include "rtl.h"
27 #include "tree.h"
28 #include "flags.h"
29 #include "expr.h"
30 #include "optabs.h"
31 #include "libfuncs.h"
32 #include "function.h"
33 #include "regs.h"
34 #include "toplev.h"
35 #include "output.h"
36 #include "tm_p.h"
37 #include "timevar.h"
38 #include "sbitmap.h"
39 #include "langhooks.h"
40 #include "target.h"
41 #include "cgraph.h"
42 #include "except.h"
44 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
45 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
47 /* Data structure and subroutines used within expand_call. */
49 struct arg_data
51 /* Tree node for this argument. */
52 tree tree_value;
53 /* Mode for value; TYPE_MODE unless promoted. */
54 enum machine_mode mode;
55 /* Current RTL value for argument, or 0 if it isn't precomputed. */
56 rtx value;
57 /* Initially-compute RTL value for argument; only for const functions. */
58 rtx initial_value;
59 /* Register to pass this argument in, 0 if passed on stack, or an
60 PARALLEL if the arg is to be copied into multiple non-contiguous
61 registers. */
62 rtx reg;
63 /* Register to pass this argument in when generating tail call sequence.
64 This is not the same register as for normal calls on machines with
65 register windows. */
66 rtx tail_call_reg;
67 /* If REG was promoted from the actual mode of the argument expression,
68 indicates whether the promotion is sign- or zero-extended. */
69 int unsignedp;
70 /* Number of registers to use. 0 means put the whole arg in registers.
71 Also 0 if not passed in registers. */
72 int partial;
73 /* Nonzero if argument must be passed on stack.
74 Note that some arguments may be passed on the stack
75 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
76 pass_on_stack identifies arguments that *cannot* go in registers. */
77 int pass_on_stack;
78 /* Some fields packaged up for locate_and_pad_parm. */
79 struct locate_and_pad_arg_data locate;
80 /* Location on the stack at which parameter should be stored. The store
81 has already been done if STACK == VALUE. */
82 rtx stack;
83 /* Location on the stack of the start of this argument slot. This can
84 differ from STACK if this arg pads downward. This location is known
85 to be aligned to FUNCTION_ARG_BOUNDARY. */
86 rtx stack_slot;
87 /* Place that this stack area has been saved, if needed. */
88 rtx save_area;
89 /* If an argument's alignment does not permit direct copying into registers,
90 copy in smaller-sized pieces into pseudos. These are stored in a
91 block pointed to by this field. The next field says how many
92 word-sized pseudos we made. */
93 rtx *aligned_regs;
94 int n_aligned_regs;
97 /* A vector of one char per byte of stack space. A byte if nonzero if
98 the corresponding stack location has been used.
99 This vector is used to prevent a function call within an argument from
100 clobbering any stack already set up. */
101 static char *stack_usage_map;
103 /* Size of STACK_USAGE_MAP. */
104 static int highest_outgoing_arg_in_use;
106 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
107 stack location's tail call argument has been already stored into the stack.
108 This bitmap is used to prevent sibling call optimization if function tries
109 to use parent's incoming argument slots when they have been already
110 overwritten with tail call arguments. */
111 static sbitmap stored_args_map;
113 /* stack_arg_under_construction is nonzero when an argument may be
114 initialized with a constructor call (including a C function that
115 returns a BLKmode struct) and expand_call must take special action
116 to make sure the object being constructed does not overlap the
117 argument list for the constructor call. */
118 int stack_arg_under_construction;
120 static int calls_function (tree, int);
121 static int calls_function_1 (tree, int);
123 static void emit_call_1 (rtx, tree, tree, HOST_WIDE_INT, HOST_WIDE_INT,
124 HOST_WIDE_INT, rtx, rtx, int, rtx, int,
125 CUMULATIVE_ARGS *);
126 static void precompute_register_parameters (int, struct arg_data *, int *);
127 static int store_one_arg (struct arg_data *, rtx, int, int, int);
128 static void store_unaligned_arguments_into_pseudos (struct arg_data *, int);
129 static int finalize_must_preallocate (int, int, struct arg_data *,
130 struct args_size *);
131 static void precompute_arguments (int, int, struct arg_data *);
132 static int compute_argument_block_size (int, struct args_size *, int);
133 static void initialize_argument_information (int, struct arg_data *,
134 struct args_size *, int, tree,
135 tree, CUMULATIVE_ARGS *, int,
136 rtx *, int *, int *, int *);
137 static void compute_argument_addresses (struct arg_data *, rtx, int);
138 static rtx rtx_for_function_call (tree, tree);
139 static void load_register_parameters (struct arg_data *, int, rtx *, int,
140 int, int *);
141 static rtx emit_library_call_value_1 (int, rtx, rtx, enum libcall_type,
142 enum machine_mode, int, va_list);
143 static int special_function_p (tree, int);
144 static rtx try_to_integrate (tree, tree, rtx, int, tree, rtx);
145 static int check_sibcall_argument_overlap_1 (rtx);
146 static int check_sibcall_argument_overlap (rtx, struct arg_data *, int);
148 static int combine_pending_stack_adjustment_and_call (int, struct args_size *,
149 int);
150 static tree fix_unsafe_tree (tree);
151 static bool shift_returned_value (tree, rtx *);
153 #ifdef REG_PARM_STACK_SPACE
154 static rtx save_fixed_argument_area (int, rtx, int *, int *);
155 static void restore_fixed_argument_area (rtx, rtx, int, int);
156 #endif
158 /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
159 `alloca'.
161 If WHICH is 0, return 1 if EXP contains a call to any function.
162 Actually, we only need return 1 if evaluating EXP would require pushing
163 arguments on the stack, but that is too difficult to compute, so we just
164 assume any function call might require the stack. */
166 static tree calls_function_save_exprs;
168 static int
169 calls_function (tree exp, int which)
171 int val;
173 calls_function_save_exprs = 0;
174 val = calls_function_1 (exp, which);
175 calls_function_save_exprs = 0;
176 return val;
179 /* Recursive function to do the work of above function. */
181 static int
182 calls_function_1 (tree exp, int which)
184 int i;
185 enum tree_code code = TREE_CODE (exp);
186 int class = TREE_CODE_CLASS (code);
187 int length = first_rtl_op (code);
189 /* If this code is language-specific, we don't know what it will do. */
190 if ((int) code >= NUM_TREE_CODES)
191 return 1;
193 switch (code)
195 case CALL_EXPR:
196 if (which == 0)
197 return 1;
198 else if ((TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))
199 == FUNCTION_TYPE)
200 && (TYPE_RETURNS_STACK_DEPRESSED
201 (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))))
202 return 1;
203 else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
204 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
205 == FUNCTION_DECL)
206 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
208 & ECF_MAY_BE_ALLOCA))
209 return 1;
211 break;
213 case CONSTRUCTOR:
215 tree tem;
217 for (tem = CONSTRUCTOR_ELTS (exp); tem != 0; tem = TREE_CHAIN (tem))
218 if (calls_function_1 (TREE_VALUE (tem), which))
219 return 1;
222 return 0;
224 case SAVE_EXPR:
225 if (SAVE_EXPR_RTL (exp) != 0)
226 return 0;
227 if (value_member (exp, calls_function_save_exprs))
228 return 0;
229 calls_function_save_exprs = tree_cons (NULL_TREE, exp,
230 calls_function_save_exprs);
231 return (TREE_OPERAND (exp, 0) != 0
232 && calls_function_1 (TREE_OPERAND (exp, 0), which));
234 case BLOCK:
236 tree local;
237 tree subblock;
239 for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
240 if (DECL_INITIAL (local) != 0
241 && calls_function_1 (DECL_INITIAL (local), which))
242 return 1;
244 for (subblock = BLOCK_SUBBLOCKS (exp);
245 subblock;
246 subblock = TREE_CHAIN (subblock))
247 if (calls_function_1 (subblock, which))
248 return 1;
250 return 0;
252 case TREE_LIST:
253 for (; exp != 0; exp = TREE_CHAIN (exp))
254 if (calls_function_1 (TREE_VALUE (exp), which))
255 return 1;
256 return 0;
258 default:
259 break;
262 /* Only expressions and blocks can contain calls. */
263 if (! IS_EXPR_CODE_CLASS (class) && class != 'b')
264 return 0;
266 for (i = 0; i < length; i++)
267 if (TREE_OPERAND (exp, i) != 0
268 && calls_function_1 (TREE_OPERAND (exp, i), which))
269 return 1;
271 return 0;
274 /* Force FUNEXP into a form suitable for the address of a CALL,
275 and return that as an rtx. Also load the static chain register
276 if FNDECL is a nested function.
278 CALL_FUSAGE points to a variable holding the prospective
279 CALL_INSN_FUNCTION_USAGE information. */
282 prepare_call_address (rtx funexp, tree fndecl, rtx *call_fusage,
283 int reg_parm_seen, int sibcallp)
285 rtx static_chain_value = 0;
287 funexp = protect_from_queue (funexp, 0);
289 if (fndecl != 0)
290 /* Get possible static chain value for nested function in C. */
291 static_chain_value = lookup_static_chain (fndecl);
293 /* Make a valid memory address and copy constants through pseudo-regs,
294 but not for a constant address if -fno-function-cse. */
295 if (GET_CODE (funexp) != SYMBOL_REF)
296 /* If we are using registers for parameters, force the
297 function address into a register now. */
298 funexp = ((SMALL_REGISTER_CLASSES && reg_parm_seen)
299 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
300 : memory_address (FUNCTION_MODE, funexp));
301 else if (! sibcallp)
303 #ifndef NO_FUNCTION_CSE
304 if (optimize && ! flag_no_function_cse)
305 #ifdef NO_RECURSIVE_FUNCTION_CSE
306 if (fndecl != current_function_decl)
307 #endif
308 funexp = force_reg (Pmode, funexp);
309 #endif
312 if (static_chain_value != 0)
314 emit_move_insn (static_chain_rtx, static_chain_value);
316 if (GET_CODE (static_chain_rtx) == REG)
317 use_reg (call_fusage, static_chain_rtx);
320 return funexp;
323 /* Generate instructions to call function FUNEXP,
324 and optionally pop the results.
325 The CALL_INSN is the first insn generated.
327 FNDECL is the declaration node of the function. This is given to the
328 macro RETURN_POPS_ARGS to determine whether this function pops its own args.
330 FUNTYPE is the data type of the function. This is given to the macro
331 RETURN_POPS_ARGS to determine whether this function pops its own args.
332 We used to allow an identifier for library functions, but that doesn't
333 work when the return type is an aggregate type and the calling convention
334 says that the pointer to this aggregate is to be popped by the callee.
336 STACK_SIZE is the number of bytes of arguments on the stack,
337 ROUNDED_STACK_SIZE is that number rounded up to
338 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
339 both to put into the call insn and to generate explicit popping
340 code if necessary.
342 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
343 It is zero if this call doesn't want a structure value.
345 NEXT_ARG_REG is the rtx that results from executing
346 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
347 just after all the args have had their registers assigned.
348 This could be whatever you like, but normally it is the first
349 arg-register beyond those used for args in this call,
350 or 0 if all the arg-registers are used in this call.
351 It is passed on to `gen_call' so you can put this info in the call insn.
353 VALREG is a hard register in which a value is returned,
354 or 0 if the call does not return a value.
356 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
357 the args to this call were processed.
358 We restore `inhibit_defer_pop' to that value.
360 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
361 denote registers used by the called function. */
363 static void
364 emit_call_1 (rtx funexp, tree fndecl ATTRIBUTE_UNUSED, tree funtype ATTRIBUTE_UNUSED,
365 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED,
366 HOST_WIDE_INT rounded_stack_size,
367 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED,
368 rtx next_arg_reg ATTRIBUTE_UNUSED, rtx valreg,
369 int old_inhibit_defer_pop, rtx call_fusage, int ecf_flags,
370 CUMULATIVE_ARGS *args_so_far ATTRIBUTE_UNUSED)
372 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
373 rtx call_insn;
374 int already_popped = 0;
375 HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
376 #if defined (HAVE_call) && defined (HAVE_call_value)
377 rtx struct_value_size_rtx;
378 struct_value_size_rtx = GEN_INT (struct_value_size);
379 #endif
381 #ifdef CALL_POPS_ARGS
382 n_popped += CALL_POPS_ARGS (* args_so_far);
383 #endif
385 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
386 and we don't want to load it into a register as an optimization,
387 because prepare_call_address already did it if it should be done. */
388 if (GET_CODE (funexp) != SYMBOL_REF)
389 funexp = memory_address (FUNCTION_MODE, funexp);
391 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
392 if ((ecf_flags & ECF_SIBCALL)
393 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
394 && (n_popped > 0 || stack_size == 0))
396 rtx n_pop = GEN_INT (n_popped);
397 rtx pat;
399 /* If this subroutine pops its own args, record that in the call insn
400 if possible, for the sake of frame pointer elimination. */
402 if (valreg)
403 pat = GEN_SIBCALL_VALUE_POP (valreg,
404 gen_rtx_MEM (FUNCTION_MODE, funexp),
405 rounded_stack_size_rtx, next_arg_reg,
406 n_pop);
407 else
408 pat = GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
409 rounded_stack_size_rtx, next_arg_reg, n_pop);
411 emit_call_insn (pat);
412 already_popped = 1;
414 else
415 #endif
417 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
418 /* If the target has "call" or "call_value" insns, then prefer them
419 if no arguments are actually popped. If the target does not have
420 "call" or "call_value" insns, then we must use the popping versions
421 even if the call has no arguments to pop. */
422 #if defined (HAVE_call) && defined (HAVE_call_value)
423 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
424 && n_popped > 0 && ! (ecf_flags & ECF_SP_DEPRESSED))
425 #else
426 if (HAVE_call_pop && HAVE_call_value_pop)
427 #endif
429 rtx n_pop = GEN_INT (n_popped);
430 rtx pat;
432 /* If this subroutine pops its own args, record that in the call insn
433 if possible, for the sake of frame pointer elimination. */
435 if (valreg)
436 pat = GEN_CALL_VALUE_POP (valreg,
437 gen_rtx_MEM (FUNCTION_MODE, funexp),
438 rounded_stack_size_rtx, next_arg_reg, n_pop);
439 else
440 pat = GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
441 rounded_stack_size_rtx, next_arg_reg, n_pop);
443 emit_call_insn (pat);
444 already_popped = 1;
446 else
447 #endif
449 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
450 if ((ecf_flags & ECF_SIBCALL)
451 && HAVE_sibcall && HAVE_sibcall_value)
453 if (valreg)
454 emit_call_insn (GEN_SIBCALL_VALUE (valreg,
455 gen_rtx_MEM (FUNCTION_MODE, funexp),
456 rounded_stack_size_rtx,
457 next_arg_reg, NULL_RTX));
458 else
459 emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
460 rounded_stack_size_rtx, next_arg_reg,
461 struct_value_size_rtx));
463 else
464 #endif
466 #if defined (HAVE_call) && defined (HAVE_call_value)
467 if (HAVE_call && HAVE_call_value)
469 if (valreg)
470 emit_call_insn (GEN_CALL_VALUE (valreg,
471 gen_rtx_MEM (FUNCTION_MODE, funexp),
472 rounded_stack_size_rtx, next_arg_reg,
473 NULL_RTX));
474 else
475 emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
476 rounded_stack_size_rtx, next_arg_reg,
477 struct_value_size_rtx));
479 else
480 #endif
481 abort ();
483 /* Find the call we just emitted. */
484 call_insn = last_call_insn ();
486 /* Mark memory as used for "pure" function call. */
487 if (ecf_flags & ECF_PURE)
488 call_fusage
489 = gen_rtx_EXPR_LIST
490 (VOIDmode,
491 gen_rtx_USE (VOIDmode,
492 gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (VOIDmode))),
493 call_fusage);
495 /* Put the register usage information there. */
496 add_function_usage_to (call_insn, call_fusage);
498 /* If this is a const call, then set the insn's unchanging bit. */
499 if (ecf_flags & (ECF_CONST | ECF_PURE))
500 CONST_OR_PURE_CALL_P (call_insn) = 1;
502 /* If this call can't throw, attach a REG_EH_REGION reg note to that
503 effect. */
504 if (ecf_flags & ECF_NOTHROW)
505 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_EH_REGION, const0_rtx,
506 REG_NOTES (call_insn));
507 else
508 note_eh_region_may_contain_throw ();
510 if (ecf_flags & ECF_NORETURN)
511 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_NORETURN, const0_rtx,
512 REG_NOTES (call_insn));
513 if (ecf_flags & ECF_ALWAYS_RETURN)
514 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_ALWAYS_RETURN, const0_rtx,
515 REG_NOTES (call_insn));
517 if (ecf_flags & ECF_RETURNS_TWICE)
519 REG_NOTES (call_insn) = gen_rtx_EXPR_LIST (REG_SETJMP, const0_rtx,
520 REG_NOTES (call_insn));
521 current_function_calls_setjmp = 1;
524 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
526 /* Restore this now, so that we do defer pops for this call's args
527 if the context of the call as a whole permits. */
528 inhibit_defer_pop = old_inhibit_defer_pop;
530 if (n_popped > 0)
532 if (!already_popped)
533 CALL_INSN_FUNCTION_USAGE (call_insn)
534 = gen_rtx_EXPR_LIST (VOIDmode,
535 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
536 CALL_INSN_FUNCTION_USAGE (call_insn));
537 rounded_stack_size -= n_popped;
538 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
539 stack_pointer_delta -= n_popped;
542 if (!ACCUMULATE_OUTGOING_ARGS)
544 /* If returning from the subroutine does not automatically pop the args,
545 we need an instruction to pop them sooner or later.
546 Perhaps do it now; perhaps just record how much space to pop later.
548 If returning from the subroutine does pop the args, indicate that the
549 stack pointer will be changed. */
551 if (rounded_stack_size != 0)
553 if (ecf_flags & (ECF_SP_DEPRESSED | ECF_NORETURN | ECF_LONGJMP))
554 /* Just pretend we did the pop. */
555 stack_pointer_delta -= rounded_stack_size;
556 else if (flag_defer_pop && inhibit_defer_pop == 0
557 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
558 pending_stack_adjust += rounded_stack_size;
559 else
560 adjust_stack (rounded_stack_size_rtx);
563 /* When we accumulate outgoing args, we must avoid any stack manipulations.
564 Restore the stack pointer to its original value now. Usually
565 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
566 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
567 popping variants of functions exist as well.
569 ??? We may optimize similar to defer_pop above, but it is
570 probably not worthwhile.
572 ??? It will be worthwhile to enable combine_stack_adjustments even for
573 such machines. */
574 else if (n_popped)
575 anti_adjust_stack (GEN_INT (n_popped));
578 /* Determine if the function identified by NAME and FNDECL is one with
579 special properties we wish to know about.
581 For example, if the function might return more than one time (setjmp), then
582 set RETURNS_TWICE to a nonzero value.
584 Similarly set LONGJMP for if the function is in the longjmp family.
586 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
587 space from the stack such as alloca. */
589 static int
590 special_function_p (tree fndecl, int flags)
592 if (! (flags & ECF_MALLOC)
593 && fndecl && DECL_NAME (fndecl)
594 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
595 /* Exclude functions not at the file scope, or not `extern',
596 since they are not the magic functions we would otherwise
597 think they are.
598 FIXME: this should be handled with attributes, not with this
599 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
600 because you can declare fork() inside a function if you
601 wish. */
602 && (DECL_CONTEXT (fndecl) == NULL_TREE
603 || TREE_CODE (DECL_CONTEXT (fndecl)) == TRANSLATION_UNIT_DECL)
604 && TREE_PUBLIC (fndecl))
606 const char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
607 const char *tname = name;
609 /* We assume that alloca will always be called by name. It
610 makes no sense to pass it as a pointer-to-function to
611 anything that does not understand its behavior. */
612 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
613 && name[0] == 'a'
614 && ! strcmp (name, "alloca"))
615 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
616 && name[0] == '_'
617 && ! strcmp (name, "__builtin_alloca"))))
618 flags |= ECF_MAY_BE_ALLOCA;
620 /* Disregard prefix _, __ or __x. */
621 if (name[0] == '_')
623 if (name[1] == '_' && name[2] == 'x')
624 tname += 3;
625 else if (name[1] == '_')
626 tname += 2;
627 else
628 tname += 1;
631 if (tname[0] == 's')
633 if ((tname[1] == 'e'
634 && (! strcmp (tname, "setjmp")
635 || ! strcmp (tname, "setjmp_syscall")))
636 || (tname[1] == 'i'
637 && ! strcmp (tname, "sigsetjmp"))
638 || (tname[1] == 'a'
639 && ! strcmp (tname, "savectx")))
640 flags |= ECF_RETURNS_TWICE;
642 if (tname[1] == 'i'
643 && ! strcmp (tname, "siglongjmp"))
644 flags |= ECF_LONGJMP;
646 else if ((tname[0] == 'q' && tname[1] == 's'
647 && ! strcmp (tname, "qsetjmp"))
648 || (tname[0] == 'v' && tname[1] == 'f'
649 && ! strcmp (tname, "vfork")))
650 flags |= ECF_RETURNS_TWICE;
652 else if (tname[0] == 'l' && tname[1] == 'o'
653 && ! strcmp (tname, "longjmp"))
654 flags |= ECF_LONGJMP;
656 else if ((tname[0] == 'f' && tname[1] == 'o'
657 && ! strcmp (tname, "fork"))
658 /* Linux specific: __clone. check NAME to insist on the
659 leading underscores, to avoid polluting the ISO / POSIX
660 namespace. */
661 || (name[0] == '_' && name[1] == '_'
662 && ! strcmp (tname, "clone"))
663 || (tname[0] == 'e' && tname[1] == 'x' && tname[2] == 'e'
664 && tname[3] == 'c' && (tname[4] == 'l' || tname[4] == 'v')
665 && (tname[5] == '\0'
666 || ((tname[5] == 'p' || tname[5] == 'e')
667 && tname[6] == '\0'))))
668 flags |= ECF_FORK_OR_EXEC;
670 return flags;
673 /* Return nonzero when tree represent call to longjmp. */
676 setjmp_call_p (tree fndecl)
678 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
681 /* Return true when exp contains alloca call. */
682 bool
683 alloca_call_p (tree exp)
685 if (TREE_CODE (exp) == CALL_EXPR
686 && TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
687 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
688 == FUNCTION_DECL)
689 && (special_function_p (TREE_OPERAND (TREE_OPERAND (exp, 0), 0),
690 0) & ECF_MAY_BE_ALLOCA))
691 return true;
692 return false;
695 /* Detect flags (function attributes) from the function decl or type node. */
698 flags_from_decl_or_type (tree exp)
700 int flags = 0;
701 tree type = exp;
703 if (DECL_P (exp))
705 struct cgraph_rtl_info *i = cgraph_rtl_info (exp);
706 type = TREE_TYPE (exp);
708 if (i)
710 if (i->pure_function)
711 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
712 if (i->const_function)
713 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
716 /* The function exp may have the `malloc' attribute. */
717 if (DECL_IS_MALLOC (exp))
718 flags |= ECF_MALLOC;
720 /* The function exp may have the `pure' attribute. */
721 if (DECL_IS_PURE (exp))
722 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
724 if (TREE_NOTHROW (exp))
725 flags |= ECF_NOTHROW;
727 if (TREE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
728 flags |= ECF_LIBCALL_BLOCK;
731 if (TREE_READONLY (exp) && ! TREE_THIS_VOLATILE (exp))
732 flags |= ECF_CONST;
734 if (TREE_THIS_VOLATILE (exp))
735 flags |= ECF_NORETURN;
737 /* Mark if the function returns with the stack pointer depressed. We
738 cannot consider it pure or constant in that case. */
739 if (TREE_CODE (type) == FUNCTION_TYPE && TYPE_RETURNS_STACK_DEPRESSED (type))
741 flags |= ECF_SP_DEPRESSED;
742 flags &= ~(ECF_PURE | ECF_CONST | ECF_LIBCALL_BLOCK);
745 return flags;
748 /* Detect flags from a CALL_EXPR. */
751 call_expr_flags (tree t)
753 int flags;
754 tree decl = get_callee_fndecl (t);
756 if (decl)
757 flags = flags_from_decl_or_type (decl);
758 else
760 t = TREE_TYPE (TREE_OPERAND (t, 0));
761 if (t && TREE_CODE (t) == POINTER_TYPE)
762 flags = flags_from_decl_or_type (TREE_TYPE (t));
763 else
764 flags = 0;
767 return flags;
770 /* Precompute all register parameters as described by ARGS, storing values
771 into fields within the ARGS array.
773 NUM_ACTUALS indicates the total number elements in the ARGS array.
775 Set REG_PARM_SEEN if we encounter a register parameter. */
777 static void
778 precompute_register_parameters (int num_actuals, struct arg_data *args, int *reg_parm_seen)
780 int i;
782 *reg_parm_seen = 0;
784 for (i = 0; i < num_actuals; i++)
785 if (args[i].reg != 0 && ! args[i].pass_on_stack)
787 *reg_parm_seen = 1;
789 if (args[i].value == 0)
791 push_temp_slots ();
792 args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
793 VOIDmode, 0);
794 preserve_temp_slots (args[i].value);
795 pop_temp_slots ();
797 /* ANSI doesn't require a sequence point here,
798 but PCC has one, so this will avoid some problems. */
799 emit_queue ();
802 /* If the value is a non-legitimate constant, force it into a
803 pseudo now. TLS symbols sometimes need a call to resolve. */
804 if (CONSTANT_P (args[i].value)
805 && !LEGITIMATE_CONSTANT_P (args[i].value))
806 args[i].value = force_reg (args[i].mode, args[i].value);
808 /* If we are to promote the function arg to a wider mode,
809 do it now. */
811 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
812 args[i].value
813 = convert_modes (args[i].mode,
814 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
815 args[i].value, args[i].unsignedp);
817 /* If the value is expensive, and we are inside an appropriately
818 short loop, put the value into a pseudo and then put the pseudo
819 into the hard reg.
821 For small register classes, also do this if this call uses
822 register parameters. This is to avoid reload conflicts while
823 loading the parameters registers. */
825 if ((! (GET_CODE (args[i].value) == REG
826 || (GET_CODE (args[i].value) == SUBREG
827 && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
828 && args[i].mode != BLKmode
829 && rtx_cost (args[i].value, SET) > COSTS_N_INSNS (1)
830 && ((SMALL_REGISTER_CLASSES && *reg_parm_seen)
831 || preserve_subexpressions_p ()))
832 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
836 #ifdef REG_PARM_STACK_SPACE
838 /* The argument list is the property of the called routine and it
839 may clobber it. If the fixed area has been used for previous
840 parameters, we must save and restore it. */
842 static rtx
843 save_fixed_argument_area (int reg_parm_stack_space, rtx argblock, int *low_to_save, int *high_to_save)
845 int low;
846 int high;
848 /* Compute the boundary of the area that needs to be saved, if any. */
849 high = reg_parm_stack_space;
850 #ifdef ARGS_GROW_DOWNWARD
851 high += 1;
852 #endif
853 if (high > highest_outgoing_arg_in_use)
854 high = highest_outgoing_arg_in_use;
856 for (low = 0; low < high; low++)
857 if (stack_usage_map[low] != 0)
859 int num_to_save;
860 enum machine_mode save_mode;
861 int delta;
862 rtx stack_area;
863 rtx save_area;
865 while (stack_usage_map[--high] == 0)
868 *low_to_save = low;
869 *high_to_save = high;
871 num_to_save = high - low + 1;
872 save_mode = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
874 /* If we don't have the required alignment, must do this
875 in BLKmode. */
876 if ((low & (MIN (GET_MODE_SIZE (save_mode),
877 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
878 save_mode = BLKmode;
880 #ifdef ARGS_GROW_DOWNWARD
881 delta = -high;
882 #else
883 delta = low;
884 #endif
885 stack_area = gen_rtx_MEM (save_mode,
886 memory_address (save_mode,
887 plus_constant (argblock,
888 delta)));
890 set_mem_align (stack_area, PARM_BOUNDARY);
891 if (save_mode == BLKmode)
893 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
894 emit_block_move (validize_mem (save_area), stack_area,
895 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
897 else
899 save_area = gen_reg_rtx (save_mode);
900 emit_move_insn (save_area, stack_area);
903 return save_area;
906 return NULL_RTX;
909 static void
910 restore_fixed_argument_area (rtx save_area, rtx argblock, int high_to_save, int low_to_save)
912 enum machine_mode save_mode = GET_MODE (save_area);
913 int delta;
914 rtx stack_area;
916 #ifdef ARGS_GROW_DOWNWARD
917 delta = -high_to_save;
918 #else
919 delta = low_to_save;
920 #endif
921 stack_area = gen_rtx_MEM (save_mode,
922 memory_address (save_mode,
923 plus_constant (argblock, delta)));
924 set_mem_align (stack_area, PARM_BOUNDARY);
926 if (save_mode != BLKmode)
927 emit_move_insn (stack_area, save_area);
928 else
929 emit_block_move (stack_area, validize_mem (save_area),
930 GEN_INT (high_to_save - low_to_save + 1),
931 BLOCK_OP_CALL_PARM);
933 #endif /* REG_PARM_STACK_SPACE */
935 /* If any elements in ARGS refer to parameters that are to be passed in
936 registers, but not in memory, and whose alignment does not permit a
937 direct copy into registers. Copy the values into a group of pseudos
938 which we will later copy into the appropriate hard registers.
940 Pseudos for each unaligned argument will be stored into the array
941 args[argnum].aligned_regs. The caller is responsible for deallocating
942 the aligned_regs array if it is nonzero. */
944 static void
945 store_unaligned_arguments_into_pseudos (struct arg_data *args, int num_actuals)
947 int i, j;
949 for (i = 0; i < num_actuals; i++)
950 if (args[i].reg != 0 && ! args[i].pass_on_stack
951 && args[i].mode == BLKmode
952 && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
953 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
955 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
956 int nregs = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
957 int endian_correction = 0;
959 args[i].n_aligned_regs = args[i].partial ? args[i].partial : nregs;
960 args[i].aligned_regs = xmalloc (sizeof (rtx) * args[i].n_aligned_regs);
962 /* Structures smaller than a word are normally aligned to the
963 least significant byte. On a BYTES_BIG_ENDIAN machine,
964 this means we must skip the empty high order bytes when
965 calculating the bit offset. */
966 if (bytes < UNITS_PER_WORD
967 #ifdef BLOCK_REG_PADDING
968 && (BLOCK_REG_PADDING (args[i].mode,
969 TREE_TYPE (args[i].tree_value), 1)
970 == downward)
971 #else
972 && BYTES_BIG_ENDIAN
973 #endif
975 endian_correction = BITS_PER_WORD - bytes * BITS_PER_UNIT;
977 for (j = 0; j < args[i].n_aligned_regs; j++)
979 rtx reg = gen_reg_rtx (word_mode);
980 rtx word = operand_subword_force (args[i].value, j, BLKmode);
981 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
983 args[i].aligned_regs[j] = reg;
984 word = extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
985 word_mode, word_mode, BITS_PER_WORD);
987 /* There is no need to restrict this code to loading items
988 in TYPE_ALIGN sized hunks. The bitfield instructions can
989 load up entire word sized registers efficiently.
991 ??? This may not be needed anymore.
992 We use to emit a clobber here but that doesn't let later
993 passes optimize the instructions we emit. By storing 0 into
994 the register later passes know the first AND to zero out the
995 bitfield being set in the register is unnecessary. The store
996 of 0 will be deleted as will at least the first AND. */
998 emit_move_insn (reg, const0_rtx);
1000 bytes -= bitsize / BITS_PER_UNIT;
1001 store_bit_field (reg, bitsize, endian_correction, word_mode,
1002 word, BITS_PER_WORD);
1007 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1008 ACTPARMS.
1010 NUM_ACTUALS is the total number of parameters.
1012 N_NAMED_ARGS is the total number of named arguments.
1014 FNDECL is the tree code for the target of this call (if known)
1016 ARGS_SO_FAR holds state needed by the target to know where to place
1017 the next argument.
1019 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1020 for arguments which are passed in registers.
1022 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1023 and may be modified by this routine.
1025 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1026 flags which may may be modified by this routine. */
1028 static void
1029 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
1030 struct arg_data *args,
1031 struct args_size *args_size,
1032 int n_named_args ATTRIBUTE_UNUSED,
1033 tree actparms, tree fndecl,
1034 CUMULATIVE_ARGS *args_so_far,
1035 int reg_parm_stack_space,
1036 rtx *old_stack_level, int *old_pending_adj,
1037 int *must_preallocate, int *ecf_flags)
1039 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1040 int inc;
1042 /* Count arg position in order args appear. */
1043 int argpos;
1045 int i;
1046 tree p;
1048 args_size->constant = 0;
1049 args_size->var = 0;
1051 /* In this loop, we consider args in the order they are written.
1052 We fill up ARGS from the front or from the back if necessary
1053 so that in any case the first arg to be pushed ends up at the front. */
1055 if (PUSH_ARGS_REVERSED)
1057 i = num_actuals - 1, inc = -1;
1058 /* In this case, must reverse order of args
1059 so that we compute and push the last arg first. */
1061 else
1063 i = 0, inc = 1;
1066 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1067 for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
1069 tree type = TREE_TYPE (TREE_VALUE (p));
1070 int unsignedp;
1071 enum machine_mode mode;
1073 args[i].tree_value = TREE_VALUE (p);
1075 /* Replace erroneous argument with constant zero. */
1076 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1077 args[i].tree_value = integer_zero_node, type = integer_type_node;
1079 /* If TYPE is a transparent union, pass things the way we would
1080 pass the first field of the union. We have already verified that
1081 the modes are the same. */
1082 if (TREE_CODE (type) == UNION_TYPE && TYPE_TRANSPARENT_UNION (type))
1083 type = TREE_TYPE (TYPE_FIELDS (type));
1085 /* Decide where to pass this arg.
1087 args[i].reg is nonzero if all or part is passed in registers.
1089 args[i].partial is nonzero if part but not all is passed in registers,
1090 and the exact value says how many words are passed in registers.
1092 args[i].pass_on_stack is nonzero if the argument must at least be
1093 computed on the stack. It may then be loaded back into registers
1094 if args[i].reg is nonzero.
1096 These decisions are driven by the FUNCTION_... macros and must agree
1097 with those made by function.c. */
1099 /* See if this argument should be passed by invisible reference. */
1100 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (type))
1101 || TREE_ADDRESSABLE (type)
1102 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
1103 || FUNCTION_ARG_PASS_BY_REFERENCE (*args_so_far, TYPE_MODE (type),
1104 type, argpos < n_named_args)
1105 #endif
1108 /* If we're compiling a thunk, pass through invisible
1109 references instead of making a copy. */
1110 if (current_function_is_thunk
1111 #ifdef FUNCTION_ARG_CALLEE_COPIES
1112 || (FUNCTION_ARG_CALLEE_COPIES (*args_so_far, TYPE_MODE (type),
1113 type, argpos < n_named_args)
1114 /* If it's in a register, we must make a copy of it too. */
1115 /* ??? Is this a sufficient test? Is there a better one? */
1116 && !(TREE_CODE (args[i].tree_value) == VAR_DECL
1117 && REG_P (DECL_RTL (args[i].tree_value)))
1118 && ! TREE_ADDRESSABLE (type))
1119 #endif
1122 /* C++ uses a TARGET_EXPR to indicate that we want to make a
1123 new object from the argument. If we are passing by
1124 invisible reference, the callee will do that for us, so we
1125 can strip off the TARGET_EXPR. This is not always safe,
1126 but it is safe in the only case where this is a useful
1127 optimization; namely, when the argument is a plain object.
1128 In that case, the frontend is just asking the backend to
1129 make a bitwise copy of the argument. */
1131 if (TREE_CODE (args[i].tree_value) == TARGET_EXPR
1132 && (DECL_P (TREE_OPERAND (args[i].tree_value, 1)))
1133 && ! REG_P (DECL_RTL (TREE_OPERAND (args[i].tree_value, 1))))
1134 args[i].tree_value = TREE_OPERAND (args[i].tree_value, 1);
1136 args[i].tree_value = build1 (ADDR_EXPR,
1137 build_pointer_type (type),
1138 args[i].tree_value);
1139 type = build_pointer_type (type);
1141 else if (TREE_CODE (args[i].tree_value) == TARGET_EXPR)
1143 /* In the V3 C++ ABI, parameters are destroyed in the caller.
1144 We implement this by passing the address of the temporary
1145 rather than expanding it into another allocated slot. */
1146 args[i].tree_value = build1 (ADDR_EXPR,
1147 build_pointer_type (type),
1148 args[i].tree_value);
1149 type = build_pointer_type (type);
1151 else
1153 /* We make a copy of the object and pass the address to the
1154 function being called. */
1155 rtx copy;
1157 if (!COMPLETE_TYPE_P (type)
1158 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
1159 || (flag_stack_check && ! STACK_CHECK_BUILTIN
1160 && (0 < compare_tree_int (TYPE_SIZE_UNIT (type),
1161 STACK_CHECK_MAX_VAR_SIZE))))
1163 /* This is a variable-sized object. Make space on the stack
1164 for it. */
1165 rtx size_rtx = expr_size (TREE_VALUE (p));
1167 if (*old_stack_level == 0)
1169 emit_stack_save (SAVE_BLOCK, old_stack_level, NULL_RTX);
1170 *old_pending_adj = pending_stack_adjust;
1171 pending_stack_adjust = 0;
1174 copy = gen_rtx_MEM (BLKmode,
1175 allocate_dynamic_stack_space
1176 (size_rtx, NULL_RTX, TYPE_ALIGN (type)));
1177 set_mem_attributes (copy, type, 1);
1179 else
1180 copy = assign_temp (type, 0, 1, 0);
1182 store_expr (args[i].tree_value, copy, 0);
1183 *ecf_flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
1185 args[i].tree_value = build1 (ADDR_EXPR,
1186 build_pointer_type (type),
1187 make_tree (type, copy));
1188 type = build_pointer_type (type);
1192 mode = TYPE_MODE (type);
1193 unsignedp = TREE_UNSIGNED (type);
1195 if (targetm.calls.promote_function_args (fndecl ? TREE_TYPE (fndecl) : 0))
1196 mode = promote_mode (type, mode, &unsignedp, 1);
1198 args[i].unsignedp = unsignedp;
1199 args[i].mode = mode;
1201 args[i].reg = FUNCTION_ARG (*args_so_far, mode, type,
1202 argpos < n_named_args);
1203 #ifdef FUNCTION_INCOMING_ARG
1204 /* If this is a sibling call and the machine has register windows, the
1205 register window has to be unwinded before calling the routine, so
1206 arguments have to go into the incoming registers. */
1207 args[i].tail_call_reg = FUNCTION_INCOMING_ARG (*args_so_far, mode, type,
1208 argpos < n_named_args);
1209 #else
1210 args[i].tail_call_reg = args[i].reg;
1211 #endif
1213 #ifdef FUNCTION_ARG_PARTIAL_NREGS
1214 if (args[i].reg)
1215 args[i].partial
1216 = FUNCTION_ARG_PARTIAL_NREGS (*args_so_far, mode, type,
1217 argpos < n_named_args);
1218 #endif
1220 args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1222 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1223 it means that we are to pass this arg in the register(s) designated
1224 by the PARALLEL, but also to pass it in the stack. */
1225 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1226 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1227 args[i].pass_on_stack = 1;
1229 /* If this is an addressable type, we must preallocate the stack
1230 since we must evaluate the object into its final location.
1232 If this is to be passed in both registers and the stack, it is simpler
1233 to preallocate. */
1234 if (TREE_ADDRESSABLE (type)
1235 || (args[i].pass_on_stack && args[i].reg != 0))
1236 *must_preallocate = 1;
1238 /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1239 we cannot consider this function call constant. */
1240 if (TREE_ADDRESSABLE (type))
1241 *ecf_flags &= ~ECF_LIBCALL_BLOCK;
1243 /* Compute the stack-size of this argument. */
1244 if (args[i].reg == 0 || args[i].partial != 0
1245 || reg_parm_stack_space > 0
1246 || args[i].pass_on_stack)
1247 locate_and_pad_parm (mode, type,
1248 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1250 #else
1251 args[i].reg != 0,
1252 #endif
1253 args[i].pass_on_stack ? 0 : args[i].partial,
1254 fndecl, args_size, &args[i].locate);
1255 #ifdef BLOCK_REG_PADDING
1256 else
1257 /* The argument is passed entirely in registers. See at which
1258 end it should be padded. */
1259 args[i].locate.where_pad =
1260 BLOCK_REG_PADDING (mode, type,
1261 int_size_in_bytes (type) <= UNITS_PER_WORD);
1262 #endif
1264 /* Update ARGS_SIZE, the total stack space for args so far. */
1266 args_size->constant += args[i].locate.size.constant;
1267 if (args[i].locate.size.var)
1268 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
1270 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1271 have been used, etc. */
1273 FUNCTION_ARG_ADVANCE (*args_so_far, TYPE_MODE (type), type,
1274 argpos < n_named_args);
1278 /* Update ARGS_SIZE to contain the total size for the argument block.
1279 Return the original constant component of the argument block's size.
1281 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1282 for arguments passed in registers. */
1284 static int
1285 compute_argument_block_size (int reg_parm_stack_space,
1286 struct args_size *args_size,
1287 int preferred_stack_boundary ATTRIBUTE_UNUSED)
1289 int unadjusted_args_size = args_size->constant;
1291 /* For accumulate outgoing args mode we don't need to align, since the frame
1292 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1293 backends from generating misaligned frame sizes. */
1294 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1295 preferred_stack_boundary = STACK_BOUNDARY;
1297 /* Compute the actual size of the argument block required. The variable
1298 and constant sizes must be combined, the size may have to be rounded,
1299 and there may be a minimum required size. */
1301 if (args_size->var)
1303 args_size->var = ARGS_SIZE_TREE (*args_size);
1304 args_size->constant = 0;
1306 preferred_stack_boundary /= BITS_PER_UNIT;
1307 if (preferred_stack_boundary > 1)
1309 /* We don't handle this case yet. To handle it correctly we have
1310 to add the delta, round and subtract the delta.
1311 Currently no machine description requires this support. */
1312 if (stack_pointer_delta & (preferred_stack_boundary - 1))
1313 abort ();
1314 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1317 if (reg_parm_stack_space > 0)
1319 args_size->var
1320 = size_binop (MAX_EXPR, args_size->var,
1321 ssize_int (reg_parm_stack_space));
1323 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1324 /* The area corresponding to register parameters is not to count in
1325 the size of the block we need. So make the adjustment. */
1326 args_size->var
1327 = size_binop (MINUS_EXPR, args_size->var,
1328 ssize_int (reg_parm_stack_space));
1329 #endif
1332 else
1334 preferred_stack_boundary /= BITS_PER_UNIT;
1335 if (preferred_stack_boundary < 1)
1336 preferred_stack_boundary = 1;
1337 args_size->constant = (((args_size->constant
1338 + stack_pointer_delta
1339 + preferred_stack_boundary - 1)
1340 / preferred_stack_boundary
1341 * preferred_stack_boundary)
1342 - stack_pointer_delta);
1344 args_size->constant = MAX (args_size->constant,
1345 reg_parm_stack_space);
1347 #ifdef MAYBE_REG_PARM_STACK_SPACE
1348 if (reg_parm_stack_space == 0)
1349 args_size->constant = 0;
1350 #endif
1352 #ifndef OUTGOING_REG_PARM_STACK_SPACE
1353 args_size->constant -= reg_parm_stack_space;
1354 #endif
1356 return unadjusted_args_size;
1359 /* Precompute parameters as needed for a function call.
1361 FLAGS is mask of ECF_* constants.
1363 NUM_ACTUALS is the number of arguments.
1365 ARGS is an array containing information for each argument; this
1366 routine fills in the INITIAL_VALUE and VALUE fields for each
1367 precomputed argument. */
1369 static void
1370 precompute_arguments (int flags, int num_actuals, struct arg_data *args)
1372 int i;
1374 /* If this function call is cse'able, precompute all the parameters.
1375 Note that if the parameter is constructed into a temporary, this will
1376 cause an additional copy because the parameter will be constructed
1377 into a temporary location and then copied into the outgoing arguments.
1378 If a parameter contains a call to alloca and this function uses the
1379 stack, precompute the parameter. */
1381 /* If we preallocated the stack space, and some arguments must be passed
1382 on the stack, then we must precompute any parameter which contains a
1383 function call which will store arguments on the stack.
1384 Otherwise, evaluating the parameter may clobber previous parameters
1385 which have already been stored into the stack. (we have code to avoid
1386 such case by saving the outgoing stack arguments, but it results in
1387 worse code) */
1389 for (i = 0; i < num_actuals; i++)
1390 if ((flags & ECF_LIBCALL_BLOCK)
1391 || calls_function (args[i].tree_value, !ACCUMULATE_OUTGOING_ARGS))
1393 enum machine_mode mode;
1395 /* If this is an addressable type, we cannot pre-evaluate it. */
1396 if (TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value)))
1397 abort ();
1399 args[i].value
1400 = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1402 /* ANSI doesn't require a sequence point here,
1403 but PCC has one, so this will avoid some problems. */
1404 emit_queue ();
1406 args[i].initial_value = args[i].value
1407 = protect_from_queue (args[i].value, 0);
1409 mode = TYPE_MODE (TREE_TYPE (args[i].tree_value));
1410 if (mode != args[i].mode)
1412 args[i].value
1413 = convert_modes (args[i].mode, mode,
1414 args[i].value, args[i].unsignedp);
1415 #ifdef PROMOTE_FOR_CALL_ONLY
1416 /* CSE will replace this only if it contains args[i].value
1417 pseudo, so convert it down to the declared mode using
1418 a SUBREG. */
1419 if (GET_CODE (args[i].value) == REG
1420 && GET_MODE_CLASS (args[i].mode) == MODE_INT)
1422 args[i].initial_value
1423 = gen_lowpart_SUBREG (mode, args[i].value);
1424 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1425 SUBREG_PROMOTED_UNSIGNED_SET (args[i].initial_value,
1426 args[i].unsignedp);
1428 #endif
1433 /* Given the current state of MUST_PREALLOCATE and information about
1434 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1435 compute and return the final value for MUST_PREALLOCATE. */
1437 static int
1438 finalize_must_preallocate (int must_preallocate, int num_actuals, struct arg_data *args, struct args_size *args_size)
1440 /* See if we have or want to preallocate stack space.
1442 If we would have to push a partially-in-regs parm
1443 before other stack parms, preallocate stack space instead.
1445 If the size of some parm is not a multiple of the required stack
1446 alignment, we must preallocate.
1448 If the total size of arguments that would otherwise create a copy in
1449 a temporary (such as a CALL) is more than half the total argument list
1450 size, preallocation is faster.
1452 Another reason to preallocate is if we have a machine (like the m88k)
1453 where stack alignment is required to be maintained between every
1454 pair of insns, not just when the call is made. However, we assume here
1455 that such machines either do not have push insns (and hence preallocation
1456 would occur anyway) or the problem is taken care of with
1457 PUSH_ROUNDING. */
1459 if (! must_preallocate)
1461 int partial_seen = 0;
1462 int copy_to_evaluate_size = 0;
1463 int i;
1465 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1467 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1468 partial_seen = 1;
1469 else if (partial_seen && args[i].reg == 0)
1470 must_preallocate = 1;
1472 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1473 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1474 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1475 || TREE_CODE (args[i].tree_value) == COND_EXPR
1476 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1477 copy_to_evaluate_size
1478 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1481 if (copy_to_evaluate_size * 2 >= args_size->constant
1482 && args_size->constant > 0)
1483 must_preallocate = 1;
1485 return must_preallocate;
1488 /* If we preallocated stack space, compute the address of each argument
1489 and store it into the ARGS array.
1491 We need not ensure it is a valid memory address here; it will be
1492 validized when it is used.
1494 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1496 static void
1497 compute_argument_addresses (struct arg_data *args, rtx argblock, int num_actuals)
1499 if (argblock)
1501 rtx arg_reg = argblock;
1502 int i, arg_offset = 0;
1504 if (GET_CODE (argblock) == PLUS)
1505 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1507 for (i = 0; i < num_actuals; i++)
1509 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
1510 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
1511 rtx addr;
1513 /* Skip this parm if it will not be passed on the stack. */
1514 if (! args[i].pass_on_stack && args[i].reg != 0)
1515 continue;
1517 if (GET_CODE (offset) == CONST_INT)
1518 addr = plus_constant (arg_reg, INTVAL (offset));
1519 else
1520 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1522 addr = plus_constant (addr, arg_offset);
1523 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1524 set_mem_align (args[i].stack, PARM_BOUNDARY);
1525 set_mem_attributes (args[i].stack,
1526 TREE_TYPE (args[i].tree_value), 1);
1528 if (GET_CODE (slot_offset) == CONST_INT)
1529 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1530 else
1531 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1533 addr = plus_constant (addr, arg_offset);
1534 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1535 set_mem_align (args[i].stack_slot, PARM_BOUNDARY);
1536 set_mem_attributes (args[i].stack_slot,
1537 TREE_TYPE (args[i].tree_value), 1);
1539 /* Function incoming arguments may overlap with sibling call
1540 outgoing arguments and we cannot allow reordering of reads
1541 from function arguments with stores to outgoing arguments
1542 of sibling calls. */
1543 set_mem_alias_set (args[i].stack, 0);
1544 set_mem_alias_set (args[i].stack_slot, 0);
1549 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1550 in a call instruction.
1552 FNDECL is the tree node for the target function. For an indirect call
1553 FNDECL will be NULL_TREE.
1555 ADDR is the operand 0 of CALL_EXPR for this call. */
1557 static rtx
1558 rtx_for_function_call (tree fndecl, tree addr)
1560 rtx funexp;
1562 /* Get the function to call, in the form of RTL. */
1563 if (fndecl)
1565 /* If this is the first use of the function, see if we need to
1566 make an external definition for it. */
1567 if (! TREE_USED (fndecl))
1569 assemble_external (fndecl);
1570 TREE_USED (fndecl) = 1;
1573 /* Get a SYMBOL_REF rtx for the function address. */
1574 funexp = XEXP (DECL_RTL (fndecl), 0);
1576 else
1577 /* Generate an rtx (probably a pseudo-register) for the address. */
1579 push_temp_slots ();
1580 funexp = expand_expr (addr, NULL_RTX, VOIDmode, 0);
1581 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1582 emit_queue ();
1584 return funexp;
1587 /* Do the register loads required for any wholly-register parms or any
1588 parms which are passed both on the stack and in a register. Their
1589 expressions were already evaluated.
1591 Mark all register-parms as living through the call, putting these USE
1592 insns in the CALL_INSN_FUNCTION_USAGE field.
1594 When IS_SIBCALL, perform the check_sibcall_overlap_argument_overlap
1595 checking, setting *SIBCALL_FAILURE if appropriate. */
1597 static void
1598 load_register_parameters (struct arg_data *args, int num_actuals,
1599 rtx *call_fusage, int flags, int is_sibcall,
1600 int *sibcall_failure)
1602 int i, j;
1604 for (i = 0; i < num_actuals; i++)
1606 rtx reg = ((flags & ECF_SIBCALL)
1607 ? args[i].tail_call_reg : args[i].reg);
1608 if (reg)
1610 int partial = args[i].partial;
1611 int nregs;
1612 int size = 0;
1613 rtx before_arg = get_last_insn ();
1614 /* Set to non-negative if must move a word at a time, even if just
1615 one word (e.g, partial == 1 && mode == DFmode). Set to -1 if
1616 we just use a normal move insn. This value can be zero if the
1617 argument is a zero size structure with no fields. */
1618 nregs = -1;
1619 if (partial)
1620 nregs = partial;
1621 else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
1623 size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1624 nregs = (size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1626 else
1627 size = GET_MODE_SIZE (args[i].mode);
1629 /* Handle calls that pass values in multiple non-contiguous
1630 locations. The Irix 6 ABI has examples of this. */
1632 if (GET_CODE (reg) == PARALLEL)
1634 tree type = TREE_TYPE (args[i].tree_value);
1635 emit_group_load (reg, args[i].value, type,
1636 int_size_in_bytes (type));
1639 /* If simple case, just do move. If normal partial, store_one_arg
1640 has already loaded the register for us. In all other cases,
1641 load the register(s) from memory. */
1643 else if (nregs == -1)
1645 emit_move_insn (reg, args[i].value);
1646 #ifdef BLOCK_REG_PADDING
1647 /* Handle case where we have a value that needs shifting
1648 up to the msb. eg. a QImode value and we're padding
1649 upward on a BYTES_BIG_ENDIAN machine. */
1650 if (size < UNITS_PER_WORD
1651 && (args[i].locate.where_pad
1652 == (BYTES_BIG_ENDIAN ? upward : downward)))
1654 rtx x;
1655 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
1657 /* Assigning REG here rather than a temp makes CALL_FUSAGE
1658 report the whole reg as used. Strictly speaking, the
1659 call only uses SIZE bytes at the msb end, but it doesn't
1660 seem worth generating rtl to say that. */
1661 reg = gen_rtx_REG (word_mode, REGNO (reg));
1662 x = expand_binop (word_mode, ashl_optab, reg,
1663 GEN_INT (shift), reg, 1, OPTAB_WIDEN);
1664 if (x != reg)
1665 emit_move_insn (reg, x);
1667 #endif
1670 /* If we have pre-computed the values to put in the registers in
1671 the case of non-aligned structures, copy them in now. */
1673 else if (args[i].n_aligned_regs != 0)
1674 for (j = 0; j < args[i].n_aligned_regs; j++)
1675 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1676 args[i].aligned_regs[j]);
1678 else if (partial == 0 || args[i].pass_on_stack)
1680 rtx mem = validize_mem (args[i].value);
1682 #ifdef BLOCK_REG_PADDING
1683 /* Handle a BLKmode that needs shifting. */
1684 if (nregs == 1 && size < UNITS_PER_WORD
1685 && args[i].locate.where_pad == downward)
1687 rtx tem = operand_subword_force (mem, 0, args[i].mode);
1688 rtx ri = gen_rtx_REG (word_mode, REGNO (reg));
1689 rtx x = gen_reg_rtx (word_mode);
1690 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
1691 optab dir = BYTES_BIG_ENDIAN ? lshr_optab : ashl_optab;
1693 emit_move_insn (x, tem);
1694 x = expand_binop (word_mode, dir, x, GEN_INT (shift),
1695 ri, 1, OPTAB_WIDEN);
1696 if (x != ri)
1697 emit_move_insn (ri, x);
1699 else
1700 #endif
1701 move_block_to_reg (REGNO (reg), mem, nregs, args[i].mode);
1704 /* When a parameter is a block, and perhaps in other cases, it is
1705 possible that it did a load from an argument slot that was
1706 already clobbered. */
1707 if (is_sibcall
1708 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
1709 *sibcall_failure = 1;
1711 /* Handle calls that pass values in multiple non-contiguous
1712 locations. The Irix 6 ABI has examples of this. */
1713 if (GET_CODE (reg) == PARALLEL)
1714 use_group_regs (call_fusage, reg);
1715 else if (nregs == -1)
1716 use_reg (call_fusage, reg);
1717 else
1718 use_regs (call_fusage, REGNO (reg), nregs == 0 ? 1 : nregs);
1723 /* Try to integrate function. See expand_inline_function for documentation
1724 about the parameters. */
1726 static rtx
1727 try_to_integrate (tree fndecl, tree actparms, rtx target, int ignore,
1728 tree type, rtx structure_value_addr)
1730 rtx temp;
1731 rtx before_call;
1732 int i;
1733 rtx old_stack_level = 0;
1734 int reg_parm_stack_space = 0;
1736 #ifdef REG_PARM_STACK_SPACE
1737 #ifdef MAYBE_REG_PARM_STACK_SPACE
1738 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
1739 #else
1740 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
1741 #endif
1742 #endif
1744 before_call = get_last_insn ();
1746 timevar_push (TV_INTEGRATION);
1748 temp = expand_inline_function (fndecl, actparms, target,
1749 ignore, type,
1750 structure_value_addr);
1752 timevar_pop (TV_INTEGRATION);
1754 /* If inlining succeeded, return. */
1755 if (temp != (rtx) (size_t) - 1)
1757 if (ACCUMULATE_OUTGOING_ARGS)
1759 /* If the outgoing argument list must be preserved, push
1760 the stack before executing the inlined function if it
1761 makes any calls. */
1763 i = reg_parm_stack_space;
1764 if (i > highest_outgoing_arg_in_use)
1765 i = highest_outgoing_arg_in_use;
1766 while (--i >= 0 && stack_usage_map[i] == 0)
1769 if (stack_arg_under_construction || i >= 0)
1771 rtx first_insn
1772 = before_call ? NEXT_INSN (before_call) : get_insns ();
1773 rtx insn = NULL_RTX, seq;
1775 /* Look for a call in the inline function code.
1776 If DECL_SAVED_INSNS (fndecl)->outgoing_args_size is
1777 nonzero then there is a call and it is not necessary
1778 to scan the insns. */
1780 if (DECL_SAVED_INSNS (fndecl)->outgoing_args_size == 0)
1781 for (insn = first_insn; insn; insn = NEXT_INSN (insn))
1782 if (GET_CODE (insn) == CALL_INSN)
1783 break;
1785 if (insn)
1787 /* Reserve enough stack space so that the largest
1788 argument list of any function call in the inline
1789 function does not overlap the argument list being
1790 evaluated. This is usually an overestimate because
1791 allocate_dynamic_stack_space reserves space for an
1792 outgoing argument list in addition to the requested
1793 space, but there is no way to ask for stack space such
1794 that an argument list of a certain length can be
1795 safely constructed.
1797 Add the stack space reserved for register arguments, if
1798 any, in the inline function. What is really needed is the
1799 largest value of reg_parm_stack_space in the inline
1800 function, but that is not available. Using the current
1801 value of reg_parm_stack_space is wrong, but gives
1802 correct results on all supported machines. */
1804 int adjust = (DECL_SAVED_INSNS (fndecl)->outgoing_args_size
1805 + reg_parm_stack_space);
1807 start_sequence ();
1808 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1809 allocate_dynamic_stack_space (GEN_INT (adjust),
1810 NULL_RTX, BITS_PER_UNIT);
1811 seq = get_insns ();
1812 end_sequence ();
1813 emit_insn_before (seq, first_insn);
1814 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1819 /* If the result is equivalent to TARGET, return TARGET to simplify
1820 checks in store_expr. They can be equivalent but not equal in the
1821 case of a function that returns BLKmode. */
1822 if (temp != target && rtx_equal_p (temp, target))
1823 return target;
1824 return temp;
1827 /* If inlining failed, mark FNDECL as needing to be compiled
1828 separately after all. If function was declared inline,
1829 give a warning. */
1830 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
1831 && optimize > 0 && !TREE_ADDRESSABLE (fndecl))
1833 warning ("%Jinlining failed in call to '%F'", fndecl, fndecl);
1834 warning ("called from here");
1836 (*lang_hooks.mark_addressable) (fndecl);
1837 return (rtx) (size_t) - 1;
1840 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1841 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1842 bytes, then we would need to push some additional bytes to pad the
1843 arguments. So, we compute an adjust to the stack pointer for an
1844 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1845 bytes. Then, when the arguments are pushed the stack will be perfectly
1846 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1847 be popped after the call. Returns the adjustment. */
1849 static int
1850 combine_pending_stack_adjustment_and_call (int unadjusted_args_size,
1851 struct args_size *args_size,
1852 int preferred_unit_stack_boundary)
1854 /* The number of bytes to pop so that the stack will be
1855 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1856 HOST_WIDE_INT adjustment;
1857 /* The alignment of the stack after the arguments are pushed, if we
1858 just pushed the arguments without adjust the stack here. */
1859 HOST_WIDE_INT unadjusted_alignment;
1861 unadjusted_alignment
1862 = ((stack_pointer_delta + unadjusted_args_size)
1863 % preferred_unit_stack_boundary);
1865 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1866 as possible -- leaving just enough left to cancel out the
1867 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1868 PENDING_STACK_ADJUST is non-negative, and congruent to
1869 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1871 /* Begin by trying to pop all the bytes. */
1872 unadjusted_alignment
1873 = (unadjusted_alignment
1874 - (pending_stack_adjust % preferred_unit_stack_boundary));
1875 adjustment = pending_stack_adjust;
1876 /* Push enough additional bytes that the stack will be aligned
1877 after the arguments are pushed. */
1878 if (preferred_unit_stack_boundary > 1)
1880 if (unadjusted_alignment > 0)
1881 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1882 else
1883 adjustment += unadjusted_alignment;
1886 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1887 bytes after the call. The right number is the entire
1888 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1889 by the arguments in the first place. */
1890 args_size->constant
1891 = pending_stack_adjust - adjustment + unadjusted_args_size;
1893 return adjustment;
1896 /* Scan X expression if it does not dereference any argument slots
1897 we already clobbered by tail call arguments (as noted in stored_args_map
1898 bitmap).
1899 Return nonzero if X expression dereferences such argument slots,
1900 zero otherwise. */
1902 static int
1903 check_sibcall_argument_overlap_1 (rtx x)
1905 RTX_CODE code;
1906 int i, j;
1907 unsigned int k;
1908 const char *fmt;
1910 if (x == NULL_RTX)
1911 return 0;
1913 code = GET_CODE (x);
1915 if (code == MEM)
1917 if (XEXP (x, 0) == current_function_internal_arg_pointer)
1918 i = 0;
1919 else if (GET_CODE (XEXP (x, 0)) == PLUS
1920 && XEXP (XEXP (x, 0), 0) ==
1921 current_function_internal_arg_pointer
1922 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
1923 i = INTVAL (XEXP (XEXP (x, 0), 1));
1924 else
1925 return 0;
1927 #ifdef ARGS_GROW_DOWNWARD
1928 i = -i - GET_MODE_SIZE (GET_MODE (x));
1929 #endif
1931 for (k = 0; k < GET_MODE_SIZE (GET_MODE (x)); k++)
1932 if (i + k < stored_args_map->n_bits
1933 && TEST_BIT (stored_args_map, i + k))
1934 return 1;
1936 return 0;
1939 /* Scan all subexpressions. */
1940 fmt = GET_RTX_FORMAT (code);
1941 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
1943 if (*fmt == 'e')
1945 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
1946 return 1;
1948 else if (*fmt == 'E')
1950 for (j = 0; j < XVECLEN (x, i); j++)
1951 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
1952 return 1;
1955 return 0;
1958 /* Scan sequence after INSN if it does not dereference any argument slots
1959 we already clobbered by tail call arguments (as noted in stored_args_map
1960 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
1961 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
1962 should be 0). Return nonzero if sequence after INSN dereferences such argument
1963 slots, zero otherwise. */
1965 static int
1966 check_sibcall_argument_overlap (rtx insn, struct arg_data *arg, int mark_stored_args_map)
1968 int low, high;
1970 if (insn == NULL_RTX)
1971 insn = get_insns ();
1972 else
1973 insn = NEXT_INSN (insn);
1975 for (; insn; insn = NEXT_INSN (insn))
1976 if (INSN_P (insn)
1977 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
1978 break;
1980 if (mark_stored_args_map)
1982 #ifdef ARGS_GROW_DOWNWARD
1983 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
1984 #else
1985 low = arg->locate.slot_offset.constant;
1986 #endif
1988 for (high = low + arg->locate.size.constant; low < high; low++)
1989 SET_BIT (stored_args_map, low);
1991 return insn != NULL_RTX;
1994 static tree
1995 fix_unsafe_tree (tree t)
1997 switch (unsafe_for_reeval (t))
1999 case 0: /* Safe. */
2000 break;
2002 case 1: /* Mildly unsafe. */
2003 t = unsave_expr (t);
2004 break;
2006 case 2: /* Wildly unsafe. */
2008 tree var = build_decl (VAR_DECL, NULL_TREE,
2009 TREE_TYPE (t));
2010 SET_DECL_RTL (var,
2011 expand_expr (t, NULL_RTX, VOIDmode, EXPAND_NORMAL));
2012 t = var;
2014 break;
2016 default:
2017 abort ();
2019 return t;
2023 /* If function value *VALUE was returned at the most significant end of a
2024 register, shift it towards the least significant end and convert it to
2025 TYPE's mode. Return true and update *VALUE if some action was needed.
2027 TYPE is the type of the function's return value, which is known not
2028 to have mode BLKmode. */
2030 static bool
2031 shift_returned_value (tree type, rtx *value)
2033 if (targetm.calls.return_in_msb (type))
2035 HOST_WIDE_INT shift;
2037 shift = (GET_MODE_BITSIZE (GET_MODE (*value))
2038 - BITS_PER_UNIT * int_size_in_bytes (type));
2039 if (shift > 0)
2041 *value = expand_binop (GET_MODE (*value), lshr_optab, *value,
2042 GEN_INT (shift), 0, 1, OPTAB_WIDEN);
2043 *value = convert_to_mode (TYPE_MODE (type), *value, 0);
2044 return true;
2047 return false;
2050 /* Generate all the code for a function call
2051 and return an rtx for its value.
2052 Store the value in TARGET (specified as an rtx) if convenient.
2053 If the value is stored in TARGET then TARGET is returned.
2054 If IGNORE is nonzero, then we ignore the value of the function call. */
2057 expand_call (tree exp, rtx target, int ignore)
2059 /* Nonzero if we are currently expanding a call. */
2060 static int currently_expanding_call = 0;
2062 /* List of actual parameters. */
2063 tree actparms = TREE_OPERAND (exp, 1);
2064 /* RTX for the function to be called. */
2065 rtx funexp;
2066 /* Sequence of insns to perform a tail recursive "call". */
2067 rtx tail_recursion_insns = NULL_RTX;
2068 /* Sequence of insns to perform a normal "call". */
2069 rtx normal_call_insns = NULL_RTX;
2070 /* Sequence of insns to perform a tail recursive "call". */
2071 rtx tail_call_insns = NULL_RTX;
2072 /* Data type of the function. */
2073 tree funtype;
2074 tree type_arg_types;
2075 /* Declaration of the function being called,
2076 or 0 if the function is computed (not known by name). */
2077 tree fndecl = 0;
2078 rtx insn;
2079 int try_tail_call = 1;
2080 int try_tail_recursion = 1;
2081 int pass;
2083 /* Register in which non-BLKmode value will be returned,
2084 or 0 if no value or if value is BLKmode. */
2085 rtx valreg;
2086 /* Address where we should return a BLKmode value;
2087 0 if value not BLKmode. */
2088 rtx structure_value_addr = 0;
2089 /* Nonzero if that address is being passed by treating it as
2090 an extra, implicit first parameter. Otherwise,
2091 it is passed by being copied directly into struct_value_rtx. */
2092 int structure_value_addr_parm = 0;
2093 /* Size of aggregate value wanted, or zero if none wanted
2094 or if we are using the non-reentrant PCC calling convention
2095 or expecting the value in registers. */
2096 HOST_WIDE_INT struct_value_size = 0;
2097 /* Nonzero if called function returns an aggregate in memory PCC style,
2098 by returning the address of where to find it. */
2099 int pcc_struct_value = 0;
2100 rtx struct_value = 0;
2102 /* Number of actual parameters in this call, including struct value addr. */
2103 int num_actuals;
2104 /* Number of named args. Args after this are anonymous ones
2105 and they must all go on the stack. */
2106 int n_named_args;
2108 /* Vector of information about each argument.
2109 Arguments are numbered in the order they will be pushed,
2110 not the order they are written. */
2111 struct arg_data *args;
2113 /* Total size in bytes of all the stack-parms scanned so far. */
2114 struct args_size args_size;
2115 struct args_size adjusted_args_size;
2116 /* Size of arguments before any adjustments (such as rounding). */
2117 int unadjusted_args_size;
2118 /* Data on reg parms scanned so far. */
2119 CUMULATIVE_ARGS args_so_far;
2120 /* Nonzero if a reg parm has been scanned. */
2121 int reg_parm_seen;
2122 /* Nonzero if this is an indirect function call. */
2124 /* Nonzero if we must avoid push-insns in the args for this call.
2125 If stack space is allocated for register parameters, but not by the
2126 caller, then it is preallocated in the fixed part of the stack frame.
2127 So the entire argument block must then be preallocated (i.e., we
2128 ignore PUSH_ROUNDING in that case). */
2130 int must_preallocate = !PUSH_ARGS;
2132 /* Size of the stack reserved for parameter registers. */
2133 int reg_parm_stack_space = 0;
2135 /* Address of space preallocated for stack parms
2136 (on machines that lack push insns), or 0 if space not preallocated. */
2137 rtx argblock = 0;
2139 /* Mask of ECF_ flags. */
2140 int flags = 0;
2141 /* Nonzero if this is a call to an inline function. */
2142 int is_integrable = 0;
2143 #ifdef REG_PARM_STACK_SPACE
2144 /* Define the boundary of the register parm stack space that needs to be
2145 saved, if any. */
2146 int low_to_save, high_to_save;
2147 rtx save_area = 0; /* Place that it is saved */
2148 #endif
2150 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2151 rtx temp_target = 0;
2152 char *initial_stack_usage_map = stack_usage_map;
2154 int old_stack_allocated;
2156 /* State variables to track stack modifications. */
2157 rtx old_stack_level = 0;
2158 int old_stack_arg_under_construction = 0;
2159 int old_pending_adj = 0;
2160 int old_inhibit_defer_pop = inhibit_defer_pop;
2162 /* Some stack pointer alterations we make are performed via
2163 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
2164 which we then also need to save/restore along the way. */
2165 int old_stack_pointer_delta = 0;
2167 rtx call_fusage;
2168 tree p = TREE_OPERAND (exp, 0);
2169 tree addr = TREE_OPERAND (exp, 0);
2170 int i;
2171 /* The alignment of the stack, in bits. */
2172 HOST_WIDE_INT preferred_stack_boundary;
2173 /* The alignment of the stack, in bytes. */
2174 HOST_WIDE_INT preferred_unit_stack_boundary;
2176 /* See if this is "nothrow" function call. */
2177 if (TREE_NOTHROW (exp))
2178 flags |= ECF_NOTHROW;
2180 /* See if we can find a DECL-node for the actual function.
2181 As a result, decide whether this is a call to an integrable function. */
2183 fndecl = get_callee_fndecl (exp);
2184 if (fndecl)
2186 if (!flag_no_inline
2187 && fndecl != current_function_decl
2188 && DECL_INLINE (fndecl)
2189 && DECL_SAVED_INSNS (fndecl)
2190 && DECL_SAVED_INSNS (fndecl)->inlinable)
2191 is_integrable = 1;
2192 else if (! TREE_ADDRESSABLE (fndecl))
2194 /* In case this function later becomes inlinable,
2195 record that there was already a non-inline call to it.
2197 Use abstraction instead of setting TREE_ADDRESSABLE
2198 directly. */
2199 if (DECL_INLINE (fndecl) && warn_inline && !flag_no_inline
2200 && optimize > 0)
2202 warning ("%Jcan't inline call to '%F'", fndecl, fndecl);
2203 warning ("called from here");
2205 (*lang_hooks.mark_addressable) (fndecl);
2208 if (ignore
2209 && lookup_attribute ("warn_unused_result",
2210 TYPE_ATTRIBUTES (TREE_TYPE (fndecl))))
2211 warning ("ignoring return value of `%D', "
2212 "declared with attribute warn_unused_result", fndecl);
2214 flags |= flags_from_decl_or_type (fndecl);
2217 /* If we don't have specific function to call, see if we have a
2218 attributes set in the type. */
2219 else
2221 if (ignore
2222 && lookup_attribute ("warn_unused_result",
2223 TYPE_ATTRIBUTES (TREE_TYPE (TREE_TYPE (p)))))
2224 warning ("ignoring return value of function "
2225 "declared with attribute warn_unused_result");
2226 flags |= flags_from_decl_or_type (TREE_TYPE (TREE_TYPE (p)));
2229 struct_value = targetm.calls.struct_value_rtx (fndecl ? TREE_TYPE (fndecl) : 0, 0);
2231 /* Warn if this value is an aggregate type,
2232 regardless of which calling convention we are using for it. */
2233 if (warn_aggregate_return && AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2234 warning ("function call has aggregate value");
2236 /* If the result of a pure or const function call is ignored (or void),
2237 and none of its arguments are volatile, we can avoid expanding the
2238 call and just evaluate the arguments for side-effects. */
2239 if ((flags & (ECF_CONST | ECF_PURE))
2240 && (ignore || target == const0_rtx
2241 || TYPE_MODE (TREE_TYPE (exp)) == VOIDmode))
2243 bool volatilep = false;
2244 tree arg;
2246 for (arg = actparms; arg; arg = TREE_CHAIN (arg))
2247 if (TREE_THIS_VOLATILE (TREE_VALUE (arg)))
2249 volatilep = true;
2250 break;
2253 if (! volatilep)
2255 for (arg = actparms; arg; arg = TREE_CHAIN (arg))
2256 expand_expr (TREE_VALUE (arg), const0_rtx,
2257 VOIDmode, EXPAND_NORMAL);
2258 return const0_rtx;
2262 #ifdef REG_PARM_STACK_SPACE
2263 #ifdef MAYBE_REG_PARM_STACK_SPACE
2264 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
2265 #else
2266 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
2267 #endif
2268 #endif
2270 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2271 if (reg_parm_stack_space > 0 && PUSH_ARGS)
2272 must_preallocate = 1;
2273 #endif
2275 /* Set up a place to return a structure. */
2277 /* Cater to broken compilers. */
2278 if (aggregate_value_p (exp, fndecl))
2280 /* This call returns a big structure. */
2281 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
2283 #ifdef PCC_STATIC_STRUCT_RETURN
2285 pcc_struct_value = 1;
2286 /* Easier than making that case work right. */
2287 if (is_integrable)
2289 /* In case this is a static function, note that it has been
2290 used. */
2291 if (! TREE_ADDRESSABLE (fndecl))
2292 (*lang_hooks.mark_addressable) (fndecl);
2293 is_integrable = 0;
2296 #else /* not PCC_STATIC_STRUCT_RETURN */
2298 struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
2300 if (CALL_EXPR_HAS_RETURN_SLOT_ADDR (exp))
2302 /* The structure value address arg is already in actparms.
2303 Pull it out. It might be nice to just leave it there, but
2304 we need to set structure_value_addr. */
2305 tree return_arg = TREE_VALUE (actparms);
2306 actparms = TREE_CHAIN (actparms);
2307 structure_value_addr = expand_expr (return_arg, NULL_RTX,
2308 VOIDmode, EXPAND_NORMAL);
2310 else if (target && GET_CODE (target) == MEM)
2311 structure_value_addr = XEXP (target, 0);
2312 else
2314 /* For variable-sized objects, we must be called with a target
2315 specified. If we were to allocate space on the stack here,
2316 we would have no way of knowing when to free it. */
2317 rtx d = assign_temp (TREE_TYPE (exp), 1, 1, 1);
2319 mark_temp_addr_taken (d);
2320 structure_value_addr = XEXP (d, 0);
2321 target = 0;
2324 #endif /* not PCC_STATIC_STRUCT_RETURN */
2327 /* If called function is inline, try to integrate it. */
2329 if (is_integrable)
2331 rtx temp = try_to_integrate (fndecl, actparms, target,
2332 ignore, TREE_TYPE (exp),
2333 structure_value_addr);
2334 if (temp != (rtx) (size_t) - 1)
2335 return temp;
2338 /* Figure out the amount to which the stack should be aligned. */
2339 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2340 if (fndecl)
2342 struct cgraph_rtl_info *i = cgraph_rtl_info (fndecl);
2343 if (i && i->preferred_incoming_stack_boundary)
2344 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
2347 /* Operand 0 is a pointer-to-function; get the type of the function. */
2348 funtype = TREE_TYPE (addr);
2349 if (! POINTER_TYPE_P (funtype))
2350 abort ();
2351 funtype = TREE_TYPE (funtype);
2353 /* Munge the tree to split complex arguments into their imaginary
2354 and real parts. */
2355 if (SPLIT_COMPLEX_ARGS)
2357 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
2358 actparms = split_complex_values (actparms);
2360 else
2361 type_arg_types = TYPE_ARG_TYPES (funtype);
2363 /* See if this is a call to a function that can return more than once
2364 or a call to longjmp or malloc. */
2365 flags |= special_function_p (fndecl, flags);
2367 if (flags & ECF_MAY_BE_ALLOCA)
2368 current_function_calls_alloca = 1;
2370 /* If struct_value_rtx is 0, it means pass the address
2371 as if it were an extra parameter. */
2372 if (structure_value_addr && struct_value == 0)
2374 /* If structure_value_addr is a REG other than
2375 virtual_outgoing_args_rtx, we can use always use it. If it
2376 is not a REG, we must always copy it into a register.
2377 If it is virtual_outgoing_args_rtx, we must copy it to another
2378 register in some cases. */
2379 rtx temp = (GET_CODE (structure_value_addr) != REG
2380 || (ACCUMULATE_OUTGOING_ARGS
2381 && stack_arg_under_construction
2382 && structure_value_addr == virtual_outgoing_args_rtx)
2383 ? copy_addr_to_reg (structure_value_addr)
2384 : structure_value_addr);
2386 actparms
2387 = tree_cons (error_mark_node,
2388 make_tree (build_pointer_type (TREE_TYPE (funtype)),
2389 temp),
2390 actparms);
2391 structure_value_addr_parm = 1;
2394 /* Count the arguments and set NUM_ACTUALS. */
2395 for (p = actparms, num_actuals = 0; p; p = TREE_CHAIN (p))
2396 num_actuals++;
2398 /* Start updating where the next arg would go.
2400 On some machines (such as the PA) indirect calls have a different
2401 calling convention than normal calls. The last argument in
2402 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2403 or not. */
2404 INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX, fndecl);
2406 /* Compute number of named args.
2407 Normally, don't include the last named arg if anonymous args follow.
2408 We do include the last named arg if
2409 targetm.calls.strict_argument_naming() returns nonzero.
2410 (If no anonymous args follow, the result of list_length is actually
2411 one too large. This is harmless.)
2413 If targetm.calls.pretend_outgoing_varargs_named() returns
2414 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2415 this machine will be able to place unnamed args that were passed
2416 in registers into the stack. So treat all args as named. This
2417 allows the insns emitting for a specific argument list to be
2418 independent of the function declaration.
2420 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2421 we do not have any reliable way to pass unnamed args in
2422 registers, so we must force them into memory. */
2424 if ((targetm.calls.strict_argument_naming (&args_so_far)
2425 || ! targetm.calls.pretend_outgoing_varargs_named (&args_so_far))
2426 && type_arg_types != 0)
2427 n_named_args
2428 = (list_length (type_arg_types)
2429 /* Don't include the last named arg. */
2430 - (targetm.calls.strict_argument_naming (&args_so_far) ? 0 : 1)
2431 /* Count the struct value address, if it is passed as a parm. */
2432 + structure_value_addr_parm);
2433 else
2434 /* If we know nothing, treat all args as named. */
2435 n_named_args = num_actuals;
2437 /* Make a vector to hold all the information about each arg. */
2438 args = alloca (num_actuals * sizeof (struct arg_data));
2439 memset (args, 0, num_actuals * sizeof (struct arg_data));
2441 /* Build up entries in the ARGS array, compute the size of the
2442 arguments into ARGS_SIZE, etc. */
2443 initialize_argument_information (num_actuals, args, &args_size,
2444 n_named_args, actparms, fndecl,
2445 &args_so_far, reg_parm_stack_space,
2446 &old_stack_level, &old_pending_adj,
2447 &must_preallocate, &flags);
2449 if (args_size.var)
2451 /* If this function requires a variable-sized argument list, don't
2452 try to make a cse'able block for this call. We may be able to
2453 do this eventually, but it is too complicated to keep track of
2454 what insns go in the cse'able block and which don't. */
2456 flags &= ~ECF_LIBCALL_BLOCK;
2457 must_preallocate = 1;
2460 /* Now make final decision about preallocating stack space. */
2461 must_preallocate = finalize_must_preallocate (must_preallocate,
2462 num_actuals, args,
2463 &args_size);
2465 /* If the structure value address will reference the stack pointer, we
2466 must stabilize it. We don't need to do this if we know that we are
2467 not going to adjust the stack pointer in processing this call. */
2469 if (structure_value_addr
2470 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2471 || reg_mentioned_p (virtual_outgoing_args_rtx,
2472 structure_value_addr))
2473 && (args_size.var
2474 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2475 structure_value_addr = copy_to_reg (structure_value_addr);
2477 /* Tail calls can make things harder to debug, and we're traditionally
2478 pushed these optimizations into -O2. Don't try if we're already
2479 expanding a call, as that means we're an argument. Don't try if
2480 there's cleanups, as we know there's code to follow the call.
2482 If rtx_equal_function_value_matters is false, that means we've
2483 finished with regular parsing. Which means that some of the
2484 machinery we use to generate tail-calls is no longer in place.
2485 This is most often true of sjlj-exceptions, which we couldn't
2486 tail-call to anyway.
2488 If current_nesting_level () == 0, we're being called after
2489 the function body has been expanded. This can happen when
2490 setting up trampolines in expand_function_end. */
2491 if (currently_expanding_call++ != 0
2492 || !flag_optimize_sibling_calls
2493 || !rtx_equal_function_value_matters
2494 || current_nesting_level () == 0
2495 || any_pending_cleanups ()
2496 || args_size.var)
2497 try_tail_call = try_tail_recursion = 0;
2499 /* Tail recursion fails, when we are not dealing with recursive calls. */
2500 if (!try_tail_recursion
2501 || TREE_CODE (addr) != ADDR_EXPR
2502 || TREE_OPERAND (addr, 0) != current_function_decl)
2503 try_tail_recursion = 0;
2505 /* Rest of purposes for tail call optimizations to fail. */
2506 if (
2507 #ifdef HAVE_sibcall_epilogue
2508 !HAVE_sibcall_epilogue
2509 #else
2511 #endif
2512 || !try_tail_call
2513 /* Doing sibling call optimization needs some work, since
2514 structure_value_addr can be allocated on the stack.
2515 It does not seem worth the effort since few optimizable
2516 sibling calls will return a structure. */
2517 || structure_value_addr != NULL_RTX
2518 /* Check whether the target is able to optimize the call
2519 into a sibcall. */
2520 || !(*targetm.function_ok_for_sibcall) (fndecl, exp)
2521 /* Functions that do not return exactly once may not be sibcall
2522 optimized. */
2523 || (flags & (ECF_RETURNS_TWICE | ECF_LONGJMP | ECF_NORETURN))
2524 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr)))
2525 /* If the called function is nested in the current one, it might access
2526 some of the caller's arguments, but could clobber them beforehand if
2527 the argument areas are shared. */
2528 || (fndecl && decl_function_context (fndecl) == current_function_decl)
2529 /* If this function requires more stack slots than the current
2530 function, we cannot change it into a sibling call. */
2531 || args_size.constant > current_function_args_size
2532 /* If the callee pops its own arguments, then it must pop exactly
2533 the same number of arguments as the current function. */
2534 || (RETURN_POPS_ARGS (fndecl, funtype, args_size.constant)
2535 != RETURN_POPS_ARGS (current_function_decl,
2536 TREE_TYPE (current_function_decl),
2537 current_function_args_size))
2538 || !(*lang_hooks.decls.ok_for_sibcall) (fndecl))
2539 try_tail_call = 0;
2541 if (try_tail_call || try_tail_recursion)
2543 int end, inc;
2544 actparms = NULL_TREE;
2545 /* Ok, we're going to give the tail call the old college try.
2546 This means we're going to evaluate the function arguments
2547 up to three times. There are two degrees of badness we can
2548 encounter, those that can be unsaved and those that can't.
2549 (See unsafe_for_reeval commentary for details.)
2551 Generate a new argument list. Pass safe arguments through
2552 unchanged. For the easy badness wrap them in UNSAVE_EXPRs.
2553 For hard badness, evaluate them now and put their resulting
2554 rtx in a temporary VAR_DECL.
2556 initialize_argument_information has ordered the array for the
2557 order to be pushed, and we must remember this when reconstructing
2558 the original argument order. */
2560 if (PUSH_ARGS_REVERSED)
2562 inc = 1;
2563 i = 0;
2564 end = num_actuals;
2566 else
2568 inc = -1;
2569 i = num_actuals - 1;
2570 end = -1;
2573 for (; i != end; i += inc)
2575 args[i].tree_value = fix_unsafe_tree (args[i].tree_value);
2576 /* We need to build actparms for optimize_tail_recursion. We can
2577 safely trash away TREE_PURPOSE, since it is unused by this
2578 function. */
2579 if (try_tail_recursion)
2580 actparms = tree_cons (NULL_TREE, args[i].tree_value, actparms);
2582 /* Do the same for the function address if it is an expression. */
2583 if (!fndecl)
2584 addr = fix_unsafe_tree (addr);
2585 /* Expanding one of those dangerous arguments could have added
2586 cleanups, but otherwise give it a whirl. */
2587 if (any_pending_cleanups ())
2588 try_tail_call = try_tail_recursion = 0;
2591 /* Generate a tail recursion sequence when calling ourselves. */
2593 if (try_tail_recursion)
2595 /* We want to emit any pending stack adjustments before the tail
2596 recursion "call". That way we know any adjustment after the tail
2597 recursion call can be ignored if we indeed use the tail recursion
2598 call expansion. */
2599 int save_pending_stack_adjust = pending_stack_adjust;
2600 int save_stack_pointer_delta = stack_pointer_delta;
2602 /* Emit any queued insns now; otherwise they would end up in
2603 only one of the alternates. */
2604 emit_queue ();
2606 /* Use a new sequence to hold any RTL we generate. We do not even
2607 know if we will use this RTL yet. The final decision can not be
2608 made until after RTL generation for the entire function is
2609 complete. */
2610 start_sequence ();
2611 /* If expanding any of the arguments creates cleanups, we can't
2612 do a tailcall. So, we'll need to pop the pending cleanups
2613 list. If, however, all goes well, and there are no cleanups
2614 then the call to expand_start_target_temps will have no
2615 effect. */
2616 expand_start_target_temps ();
2617 if (optimize_tail_recursion (actparms, get_last_insn ()))
2619 if (any_pending_cleanups ())
2620 try_tail_call = try_tail_recursion = 0;
2621 else
2622 tail_recursion_insns = get_insns ();
2624 expand_end_target_temps ();
2625 end_sequence ();
2627 /* Restore the original pending stack adjustment for the sibling and
2628 normal call cases below. */
2629 pending_stack_adjust = save_pending_stack_adjust;
2630 stack_pointer_delta = save_stack_pointer_delta;
2633 if (profile_arc_flag && (flags & ECF_FORK_OR_EXEC))
2635 /* A fork duplicates the profile information, and an exec discards
2636 it. We can't rely on fork/exec to be paired. So write out the
2637 profile information we have gathered so far, and clear it. */
2638 /* ??? When Linux's __clone is called with CLONE_VM set, profiling
2639 is subject to race conditions, just as with multithreaded
2640 programs. */
2642 emit_library_call (gcov_flush_libfunc, LCT_ALWAYS_RETURN, VOIDmode, 0);
2645 /* Ensure current function's preferred stack boundary is at least
2646 what we need. We don't have to increase alignment for recursive
2647 functions. */
2648 if (cfun->preferred_stack_boundary < preferred_stack_boundary
2649 && fndecl != current_function_decl)
2650 cfun->preferred_stack_boundary = preferred_stack_boundary;
2651 if (fndecl == current_function_decl)
2652 cfun->recursive_call_emit = true;
2654 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2656 function_call_count++;
2658 /* We want to make two insn chains; one for a sibling call, the other
2659 for a normal call. We will select one of the two chains after
2660 initial RTL generation is complete. */
2661 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
2663 int sibcall_failure = 0;
2664 /* We want to emit any pending stack adjustments before the tail
2665 recursion "call". That way we know any adjustment after the tail
2666 recursion call can be ignored if we indeed use the tail recursion
2667 call expansion. */
2668 int save_pending_stack_adjust = 0;
2669 int save_stack_pointer_delta = 0;
2670 rtx insns;
2671 rtx before_call, next_arg_reg;
2673 if (pass == 0)
2675 /* Emit any queued insns now; otherwise they would end up in
2676 only one of the alternates. */
2677 emit_queue ();
2679 /* State variables we need to save and restore between
2680 iterations. */
2681 save_pending_stack_adjust = pending_stack_adjust;
2682 save_stack_pointer_delta = stack_pointer_delta;
2684 if (pass)
2685 flags &= ~ECF_SIBCALL;
2686 else
2687 flags |= ECF_SIBCALL;
2689 /* Other state variables that we must reinitialize each time
2690 through the loop (that are not initialized by the loop itself). */
2691 argblock = 0;
2692 call_fusage = 0;
2694 /* Start a new sequence for the normal call case.
2696 From this point on, if the sibling call fails, we want to set
2697 sibcall_failure instead of continuing the loop. */
2698 start_sequence ();
2700 if (pass == 0)
2702 /* We know at this point that there are not currently any
2703 pending cleanups. If, however, in the process of evaluating
2704 the arguments we were to create some, we'll need to be
2705 able to get rid of them. */
2706 expand_start_target_temps ();
2709 /* Don't let pending stack adjusts add up to too much.
2710 Also, do all pending adjustments now if there is any chance
2711 this might be a call to alloca or if we are expanding a sibling
2712 call sequence or if we are calling a function that is to return
2713 with stack pointer depressed. */
2714 if (pending_stack_adjust >= 32
2715 || (pending_stack_adjust > 0
2716 && (flags & (ECF_MAY_BE_ALLOCA | ECF_SP_DEPRESSED)))
2717 || pass == 0)
2718 do_pending_stack_adjust ();
2720 /* When calling a const function, we must pop the stack args right away,
2721 so that the pop is deleted or moved with the call. */
2722 if (pass && (flags & ECF_LIBCALL_BLOCK))
2723 NO_DEFER_POP;
2725 #ifdef FINAL_REG_PARM_STACK_SPACE
2726 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
2727 args_size.var);
2728 #endif
2729 /* Precompute any arguments as needed. */
2730 if (pass)
2731 precompute_arguments (flags, num_actuals, args);
2733 /* Now we are about to start emitting insns that can be deleted
2734 if a libcall is deleted. */
2735 if (pass && (flags & (ECF_LIBCALL_BLOCK | ECF_MALLOC)))
2736 start_sequence ();
2738 adjusted_args_size = args_size;
2739 /* Compute the actual size of the argument block required. The variable
2740 and constant sizes must be combined, the size may have to be rounded,
2741 and there may be a minimum required size. When generating a sibcall
2742 pattern, do not round up, since we'll be re-using whatever space our
2743 caller provided. */
2744 unadjusted_args_size
2745 = compute_argument_block_size (reg_parm_stack_space,
2746 &adjusted_args_size,
2747 (pass == 0 ? 0
2748 : preferred_stack_boundary));
2750 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2752 /* The argument block when performing a sibling call is the
2753 incoming argument block. */
2754 if (pass == 0)
2756 argblock = virtual_incoming_args_rtx;
2757 argblock
2758 #ifdef STACK_GROWS_DOWNWARD
2759 = plus_constant (argblock, current_function_pretend_args_size);
2760 #else
2761 = plus_constant (argblock, -current_function_pretend_args_size);
2762 #endif
2763 stored_args_map = sbitmap_alloc (args_size.constant);
2764 sbitmap_zero (stored_args_map);
2767 /* If we have no actual push instructions, or shouldn't use them,
2768 make space for all args right now. */
2769 else if (adjusted_args_size.var != 0)
2771 if (old_stack_level == 0)
2773 emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
2774 old_stack_pointer_delta = stack_pointer_delta;
2775 old_pending_adj = pending_stack_adjust;
2776 pending_stack_adjust = 0;
2777 /* stack_arg_under_construction says whether a stack arg is
2778 being constructed at the old stack level. Pushing the stack
2779 gets a clean outgoing argument block. */
2780 old_stack_arg_under_construction = stack_arg_under_construction;
2781 stack_arg_under_construction = 0;
2783 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2785 else
2787 /* Note that we must go through the motions of allocating an argument
2788 block even if the size is zero because we may be storing args
2789 in the area reserved for register arguments, which may be part of
2790 the stack frame. */
2792 int needed = adjusted_args_size.constant;
2794 /* Store the maximum argument space used. It will be pushed by
2795 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2796 checking). */
2798 if (needed > current_function_outgoing_args_size)
2799 current_function_outgoing_args_size = needed;
2801 if (must_preallocate)
2803 if (ACCUMULATE_OUTGOING_ARGS)
2805 /* Since the stack pointer will never be pushed, it is
2806 possible for the evaluation of a parm to clobber
2807 something we have already written to the stack.
2808 Since most function calls on RISC machines do not use
2809 the stack, this is uncommon, but must work correctly.
2811 Therefore, we save any area of the stack that was already
2812 written and that we are using. Here we set up to do this
2813 by making a new stack usage map from the old one. The
2814 actual save will be done by store_one_arg.
2816 Another approach might be to try to reorder the argument
2817 evaluations to avoid this conflicting stack usage. */
2819 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2820 /* Since we will be writing into the entire argument area,
2821 the map must be allocated for its entire size, not just
2822 the part that is the responsibility of the caller. */
2823 needed += reg_parm_stack_space;
2824 #endif
2826 #ifdef ARGS_GROW_DOWNWARD
2827 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2828 needed + 1);
2829 #else
2830 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2831 needed);
2832 #endif
2833 stack_usage_map = alloca (highest_outgoing_arg_in_use);
2835 if (initial_highest_arg_in_use)
2836 memcpy (stack_usage_map, initial_stack_usage_map,
2837 initial_highest_arg_in_use);
2839 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2840 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2841 (highest_outgoing_arg_in_use
2842 - initial_highest_arg_in_use));
2843 needed = 0;
2845 /* The address of the outgoing argument list must not be
2846 copied to a register here, because argblock would be left
2847 pointing to the wrong place after the call to
2848 allocate_dynamic_stack_space below. */
2850 argblock = virtual_outgoing_args_rtx;
2852 else
2854 if (inhibit_defer_pop == 0)
2856 /* Try to reuse some or all of the pending_stack_adjust
2857 to get this space. */
2858 needed
2859 = (combine_pending_stack_adjustment_and_call
2860 (unadjusted_args_size,
2861 &adjusted_args_size,
2862 preferred_unit_stack_boundary));
2864 /* combine_pending_stack_adjustment_and_call computes
2865 an adjustment before the arguments are allocated.
2866 Account for them and see whether or not the stack
2867 needs to go up or down. */
2868 needed = unadjusted_args_size - needed;
2870 if (needed < 0)
2872 /* We're releasing stack space. */
2873 /* ??? We can avoid any adjustment at all if we're
2874 already aligned. FIXME. */
2875 pending_stack_adjust = -needed;
2876 do_pending_stack_adjust ();
2877 needed = 0;
2879 else
2880 /* We need to allocate space. We'll do that in
2881 push_block below. */
2882 pending_stack_adjust = 0;
2885 /* Special case this because overhead of `push_block' in
2886 this case is non-trivial. */
2887 if (needed == 0)
2888 argblock = virtual_outgoing_args_rtx;
2889 else
2891 argblock = push_block (GEN_INT (needed), 0, 0);
2892 #ifdef ARGS_GROW_DOWNWARD
2893 argblock = plus_constant (argblock, needed);
2894 #endif
2897 /* We only really need to call `copy_to_reg' in the case
2898 where push insns are going to be used to pass ARGBLOCK
2899 to a function call in ARGS. In that case, the stack
2900 pointer changes value from the allocation point to the
2901 call point, and hence the value of
2902 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2903 as well always do it. */
2904 argblock = copy_to_reg (argblock);
2909 if (ACCUMULATE_OUTGOING_ARGS)
2911 /* The save/restore code in store_one_arg handles all
2912 cases except one: a constructor call (including a C
2913 function returning a BLKmode struct) to initialize
2914 an argument. */
2915 if (stack_arg_under_construction)
2917 #ifndef OUTGOING_REG_PARM_STACK_SPACE
2918 rtx push_size = GEN_INT (reg_parm_stack_space
2919 + adjusted_args_size.constant);
2920 #else
2921 rtx push_size = GEN_INT (adjusted_args_size.constant);
2922 #endif
2923 if (old_stack_level == 0)
2925 emit_stack_save (SAVE_BLOCK, &old_stack_level,
2926 NULL_RTX);
2927 old_stack_pointer_delta = stack_pointer_delta;
2928 old_pending_adj = pending_stack_adjust;
2929 pending_stack_adjust = 0;
2930 /* stack_arg_under_construction says whether a stack
2931 arg is being constructed at the old stack level.
2932 Pushing the stack gets a clean outgoing argument
2933 block. */
2934 old_stack_arg_under_construction
2935 = stack_arg_under_construction;
2936 stack_arg_under_construction = 0;
2937 /* Make a new map for the new argument list. */
2938 stack_usage_map = alloca (highest_outgoing_arg_in_use);
2939 memset (stack_usage_map, 0, highest_outgoing_arg_in_use);
2940 highest_outgoing_arg_in_use = 0;
2942 allocate_dynamic_stack_space (push_size, NULL_RTX,
2943 BITS_PER_UNIT);
2946 /* If argument evaluation might modify the stack pointer,
2947 copy the address of the argument list to a register. */
2948 for (i = 0; i < num_actuals; i++)
2949 if (args[i].pass_on_stack)
2951 argblock = copy_addr_to_reg (argblock);
2952 break;
2956 compute_argument_addresses (args, argblock, num_actuals);
2958 /* If we push args individually in reverse order, perform stack alignment
2959 before the first push (the last arg). */
2960 if (PUSH_ARGS_REVERSED && argblock == 0
2961 && adjusted_args_size.constant != unadjusted_args_size)
2963 /* When the stack adjustment is pending, we get better code
2964 by combining the adjustments. */
2965 if (pending_stack_adjust
2966 && ! (flags & ECF_LIBCALL_BLOCK)
2967 && ! inhibit_defer_pop)
2969 pending_stack_adjust
2970 = (combine_pending_stack_adjustment_and_call
2971 (unadjusted_args_size,
2972 &adjusted_args_size,
2973 preferred_unit_stack_boundary));
2974 do_pending_stack_adjust ();
2976 else if (argblock == 0)
2977 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2978 - unadjusted_args_size));
2980 /* Now that the stack is properly aligned, pops can't safely
2981 be deferred during the evaluation of the arguments. */
2982 NO_DEFER_POP;
2984 funexp = rtx_for_function_call (fndecl, addr);
2986 /* Figure out the register where the value, if any, will come back. */
2987 valreg = 0;
2988 if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
2989 && ! structure_value_addr)
2991 if (pcc_struct_value)
2992 valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
2993 fndecl, (pass == 0));
2994 else
2995 valreg = hard_function_value (TREE_TYPE (exp), fndecl, (pass == 0));
2998 /* Precompute all register parameters. It isn't safe to compute anything
2999 once we have started filling any specific hard regs. */
3000 precompute_register_parameters (num_actuals, args, &reg_parm_seen);
3002 #ifdef REG_PARM_STACK_SPACE
3003 /* Save the fixed argument area if it's part of the caller's frame and
3004 is clobbered by argument setup for this call. */
3005 if (ACCUMULATE_OUTGOING_ARGS && pass)
3006 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3007 &low_to_save, &high_to_save);
3008 #endif
3010 /* Now store (and compute if necessary) all non-register parms.
3011 These come before register parms, since they can require block-moves,
3012 which could clobber the registers used for register parms.
3013 Parms which have partial registers are not stored here,
3014 but we do preallocate space here if they want that. */
3016 for (i = 0; i < num_actuals; i++)
3017 if (args[i].reg == 0 || args[i].pass_on_stack)
3019 rtx before_arg = get_last_insn ();
3021 if (store_one_arg (&args[i], argblock, flags,
3022 adjusted_args_size.var != 0,
3023 reg_parm_stack_space)
3024 || (pass == 0
3025 && check_sibcall_argument_overlap (before_arg,
3026 &args[i], 1)))
3027 sibcall_failure = 1;
3029 if (flags & ECF_CONST
3030 && args[i].stack
3031 && args[i].value == args[i].stack)
3032 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3033 gen_rtx_USE (VOIDmode,
3034 args[i].value),
3035 call_fusage);
3038 /* If we have a parm that is passed in registers but not in memory
3039 and whose alignment does not permit a direct copy into registers,
3040 make a group of pseudos that correspond to each register that we
3041 will later fill. */
3042 if (STRICT_ALIGNMENT)
3043 store_unaligned_arguments_into_pseudos (args, num_actuals);
3045 /* Now store any partially-in-registers parm.
3046 This is the last place a block-move can happen. */
3047 if (reg_parm_seen)
3048 for (i = 0; i < num_actuals; i++)
3049 if (args[i].partial != 0 && ! args[i].pass_on_stack)
3051 rtx before_arg = get_last_insn ();
3053 if (store_one_arg (&args[i], argblock, flags,
3054 adjusted_args_size.var != 0,
3055 reg_parm_stack_space)
3056 || (pass == 0
3057 && check_sibcall_argument_overlap (before_arg,
3058 &args[i], 1)))
3059 sibcall_failure = 1;
3062 /* If we pushed args in forward order, perform stack alignment
3063 after pushing the last arg. */
3064 if (!PUSH_ARGS_REVERSED && argblock == 0)
3065 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3066 - unadjusted_args_size));
3068 /* If register arguments require space on the stack and stack space
3069 was not preallocated, allocate stack space here for arguments
3070 passed in registers. */
3071 #ifdef OUTGOING_REG_PARM_STACK_SPACE
3072 if (!ACCUMULATE_OUTGOING_ARGS
3073 && must_preallocate == 0 && reg_parm_stack_space > 0)
3074 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3075 #endif
3077 /* Pass the function the address in which to return a
3078 structure value. */
3079 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3081 structure_value_addr
3082 = convert_memory_address (Pmode, structure_value_addr);
3083 emit_move_insn (struct_value,
3084 force_reg (Pmode,
3085 force_operand (structure_value_addr,
3086 NULL_RTX)));
3088 if (GET_CODE (struct_value) == REG)
3089 use_reg (&call_fusage, struct_value);
3092 funexp = prepare_call_address (funexp, fndecl, &call_fusage,
3093 reg_parm_seen, pass == 0);
3095 load_register_parameters (args, num_actuals, &call_fusage, flags,
3096 pass == 0, &sibcall_failure);
3098 /* Perform postincrements before actually calling the function. */
3099 emit_queue ();
3101 /* Save a pointer to the last insn before the call, so that we can
3102 later safely search backwards to find the CALL_INSN. */
3103 before_call = get_last_insn ();
3105 /* Set up next argument register. For sibling calls on machines
3106 with register windows this should be the incoming register. */
3107 #ifdef FUNCTION_INCOMING_ARG
3108 if (pass == 0)
3109 next_arg_reg = FUNCTION_INCOMING_ARG (args_so_far, VOIDmode,
3110 void_type_node, 1);
3111 else
3112 #endif
3113 next_arg_reg = FUNCTION_ARG (args_so_far, VOIDmode,
3114 void_type_node, 1);
3116 /* All arguments and registers used for the call must be set up by
3117 now! */
3119 /* Stack must be properly aligned now. */
3120 if (pass && stack_pointer_delta % preferred_unit_stack_boundary)
3121 abort ();
3123 /* Generate the actual call instruction. */
3124 emit_call_1 (funexp, fndecl, funtype, unadjusted_args_size,
3125 adjusted_args_size.constant, struct_value_size,
3126 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3127 flags, & args_so_far);
3129 /* If call is cse'able, make appropriate pair of reg-notes around it.
3130 Test valreg so we don't crash; may safely ignore `const'
3131 if return type is void. Disable for PARALLEL return values, because
3132 we have no way to move such values into a pseudo register. */
3133 if (pass && (flags & ECF_LIBCALL_BLOCK))
3135 rtx insns;
3136 rtx insn;
3137 bool failed = valreg == 0 || GET_CODE (valreg) == PARALLEL;
3139 insns = get_insns ();
3141 /* Expansion of block moves possibly introduced a loop that may
3142 not appear inside libcall block. */
3143 for (insn = insns; insn; insn = NEXT_INSN (insn))
3144 if (GET_CODE (insn) == JUMP_INSN)
3145 failed = true;
3147 if (failed)
3149 end_sequence ();
3150 emit_insn (insns);
3152 else
3154 rtx note = 0;
3155 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3157 /* Mark the return value as a pointer if needed. */
3158 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3159 mark_reg_pointer (temp,
3160 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))));
3162 end_sequence ();
3163 if (flag_unsafe_math_optimizations
3164 && fndecl
3165 && DECL_BUILT_IN (fndecl)
3166 && (DECL_FUNCTION_CODE (fndecl) == BUILT_IN_SQRT
3167 || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_SQRTF
3168 || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_SQRTL))
3169 note = gen_rtx_fmt_e (SQRT,
3170 GET_MODE (temp),
3171 args[0].initial_value);
3172 else
3174 /* Construct an "equal form" for the value which
3175 mentions all the arguments in order as well as
3176 the function name. */
3177 for (i = 0; i < num_actuals; i++)
3178 note = gen_rtx_EXPR_LIST (VOIDmode,
3179 args[i].initial_value, note);
3180 note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
3182 if (flags & ECF_PURE)
3183 note = gen_rtx_EXPR_LIST (VOIDmode,
3184 gen_rtx_USE (VOIDmode,
3185 gen_rtx_MEM (BLKmode,
3186 gen_rtx_SCRATCH (VOIDmode))),
3187 note);
3189 emit_libcall_block (insns, temp, valreg, note);
3191 valreg = temp;
3194 else if (pass && (flags & ECF_MALLOC))
3196 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3197 rtx last, insns;
3199 /* The return value from a malloc-like function is a pointer. */
3200 if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE)
3201 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3203 emit_move_insn (temp, valreg);
3205 /* The return value from a malloc-like function can not alias
3206 anything else. */
3207 last = get_last_insn ();
3208 REG_NOTES (last) =
3209 gen_rtx_EXPR_LIST (REG_NOALIAS, temp, REG_NOTES (last));
3211 /* Write out the sequence. */
3212 insns = get_insns ();
3213 end_sequence ();
3214 emit_insn (insns);
3215 valreg = temp;
3218 /* For calls to `setjmp', etc., inform flow.c it should complain
3219 if nonvolatile values are live. For functions that cannot return,
3220 inform flow that control does not fall through. */
3222 if ((flags & (ECF_NORETURN | ECF_LONGJMP)) || pass == 0)
3224 /* The barrier must be emitted
3225 immediately after the CALL_INSN. Some ports emit more
3226 than just a CALL_INSN above, so we must search for it here. */
3228 rtx last = get_last_insn ();
3229 while (GET_CODE (last) != CALL_INSN)
3231 last = PREV_INSN (last);
3232 /* There was no CALL_INSN? */
3233 if (last == before_call)
3234 abort ();
3237 emit_barrier_after (last);
3239 /* Stack adjustments after a noreturn call are dead code.
3240 However when NO_DEFER_POP is in effect, we must preserve
3241 stack_pointer_delta. */
3242 if (inhibit_defer_pop == 0)
3244 stack_pointer_delta = old_stack_allocated;
3245 pending_stack_adjust = 0;
3249 if (flags & ECF_LONGJMP)
3250 current_function_calls_longjmp = 1;
3252 /* If value type not void, return an rtx for the value. */
3254 /* If there are cleanups to be called, don't use a hard reg as target.
3255 We need to double check this and see if it matters anymore. */
3256 if (any_pending_cleanups ())
3258 if (target && REG_P (target)
3259 && REGNO (target) < FIRST_PSEUDO_REGISTER)
3260 target = 0;
3261 sibcall_failure = 1;
3264 if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
3265 || ignore)
3266 target = const0_rtx;
3267 else if (structure_value_addr)
3269 if (target == 0 || GET_CODE (target) != MEM)
3271 target
3272 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3273 memory_address (TYPE_MODE (TREE_TYPE (exp)),
3274 structure_value_addr));
3275 set_mem_attributes (target, exp, 1);
3278 else if (pcc_struct_value)
3280 /* This is the special C++ case where we need to
3281 know what the true target was. We take care to
3282 never use this value more than once in one expression. */
3283 target = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
3284 copy_to_reg (valreg));
3285 set_mem_attributes (target, exp, 1);
3287 /* Handle calls that return values in multiple non-contiguous locations.
3288 The Irix 6 ABI has examples of this. */
3289 else if (GET_CODE (valreg) == PARALLEL)
3291 /* Second condition is added because "target" is freed at the
3292 the end of "pass0" for -O2 when call is made to
3293 expand_end_target_temps (). Its "in_use" flag has been set
3294 to false, so allocate a new temp. */
3295 if (target == 0 || (pass == 1 && target == temp_target))
3297 /* This will only be assigned once, so it can be readonly. */
3298 tree nt = build_qualified_type (TREE_TYPE (exp),
3299 (TYPE_QUALS (TREE_TYPE (exp))
3300 | TYPE_QUAL_CONST));
3302 target = assign_temp (nt, 0, 1, 1);
3303 temp_target = target;
3304 preserve_temp_slots (target);
3307 if (! rtx_equal_p (target, valreg))
3308 emit_group_store (target, valreg, TREE_TYPE (exp),
3309 int_size_in_bytes (TREE_TYPE (exp)));
3311 /* We can not support sibling calls for this case. */
3312 sibcall_failure = 1;
3314 else if (target
3315 && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
3316 && GET_MODE (target) == GET_MODE (valreg))
3318 /* TARGET and VALREG cannot be equal at this point because the
3319 latter would not have REG_FUNCTION_VALUE_P true, while the
3320 former would if it were referring to the same register.
3322 If they refer to the same register, this move will be a no-op,
3323 except when function inlining is being done. */
3324 emit_move_insn (target, valreg);
3326 /* If we are setting a MEM, this code must be executed. Since it is
3327 emitted after the call insn, sibcall optimization cannot be
3328 performed in that case. */
3329 if (GET_CODE (target) == MEM)
3330 sibcall_failure = 1;
3332 else if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
3334 target = copy_blkmode_from_reg (target, valreg, TREE_TYPE (exp));
3336 /* We can not support sibling calls for this case. */
3337 sibcall_failure = 1;
3339 else
3341 if (shift_returned_value (TREE_TYPE (exp), &valreg))
3342 sibcall_failure = 1;
3344 target = copy_to_reg (valreg);
3347 if (targetm.calls.promote_function_return(funtype))
3349 /* If we promoted this return value, make the proper SUBREG. TARGET
3350 might be const0_rtx here, so be careful. */
3351 if (GET_CODE (target) == REG
3352 && TYPE_MODE (TREE_TYPE (exp)) != BLKmode
3353 && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
3355 tree type = TREE_TYPE (exp);
3356 int unsignedp = TREE_UNSIGNED (type);
3357 int offset = 0;
3359 /* If we don't promote as expected, something is wrong. */
3360 if (GET_MODE (target)
3361 != promote_mode (type, TYPE_MODE (type), &unsignedp, 1))
3362 abort ();
3364 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3365 && GET_MODE_SIZE (GET_MODE (target))
3366 > GET_MODE_SIZE (TYPE_MODE (type)))
3368 offset = GET_MODE_SIZE (GET_MODE (target))
3369 - GET_MODE_SIZE (TYPE_MODE (type));
3370 if (! BYTES_BIG_ENDIAN)
3371 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3372 else if (! WORDS_BIG_ENDIAN)
3373 offset %= UNITS_PER_WORD;
3375 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3376 SUBREG_PROMOTED_VAR_P (target) = 1;
3377 SUBREG_PROMOTED_UNSIGNED_SET (target, unsignedp);
3381 /* If size of args is variable or this was a constructor call for a stack
3382 argument, restore saved stack-pointer value. */
3384 if (old_stack_level && ! (flags & ECF_SP_DEPRESSED))
3386 emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
3387 stack_pointer_delta = old_stack_pointer_delta;
3388 pending_stack_adjust = old_pending_adj;
3389 stack_arg_under_construction = old_stack_arg_under_construction;
3390 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3391 stack_usage_map = initial_stack_usage_map;
3392 sibcall_failure = 1;
3394 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3396 #ifdef REG_PARM_STACK_SPACE
3397 if (save_area)
3398 restore_fixed_argument_area (save_area, argblock,
3399 high_to_save, low_to_save);
3400 #endif
3402 /* If we saved any argument areas, restore them. */
3403 for (i = 0; i < num_actuals; i++)
3404 if (args[i].save_area)
3406 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3407 rtx stack_area
3408 = gen_rtx_MEM (save_mode,
3409 memory_address (save_mode,
3410 XEXP (args[i].stack_slot, 0)));
3412 if (save_mode != BLKmode)
3413 emit_move_insn (stack_area, args[i].save_area);
3414 else
3415 emit_block_move (stack_area, args[i].save_area,
3416 GEN_INT (args[i].locate.size.constant),
3417 BLOCK_OP_CALL_PARM);
3420 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3421 stack_usage_map = initial_stack_usage_map;
3424 /* If this was alloca, record the new stack level for nonlocal gotos.
3425 Check for the handler slots since we might not have a save area
3426 for non-local gotos. */
3428 if ((flags & ECF_MAY_BE_ALLOCA) && nonlocal_goto_handler_slots != 0)
3429 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
3431 /* Free up storage we no longer need. */
3432 for (i = 0; i < num_actuals; ++i)
3433 if (args[i].aligned_regs)
3434 free (args[i].aligned_regs);
3436 if (pass == 0)
3438 /* Undo the fake expand_start_target_temps we did earlier. If
3439 there had been any cleanups created, we've already set
3440 sibcall_failure. */
3441 expand_end_target_temps ();
3444 /* If this function is returning into a memory location marked as
3445 readonly, it means it is initializing that location. We normally treat
3446 functions as not clobbering such locations, so we need to specify that
3447 this one does. We do this by adding the appropriate CLOBBER to the
3448 CALL_INSN function usage list. This cannot be done by emitting a
3449 standalone CLOBBER after the call because the latter would be ignored
3450 by at least the delay slot scheduling pass. We do this now instead of
3451 adding to call_fusage before the call to emit_call_1 because TARGET
3452 may be modified in the meantime. */
3453 if (structure_value_addr != 0 && target != 0
3454 && GET_CODE (target) == MEM && RTX_UNCHANGING_P (target))
3455 add_function_usage_to
3456 (last_call_insn (),
3457 gen_rtx_EXPR_LIST (VOIDmode, gen_rtx_CLOBBER (VOIDmode, target),
3458 NULL_RTX));
3460 insns = get_insns ();
3461 end_sequence ();
3463 if (pass == 0)
3465 tail_call_insns = insns;
3467 /* Restore the pending stack adjustment now that we have
3468 finished generating the sibling call sequence. */
3470 pending_stack_adjust = save_pending_stack_adjust;
3471 stack_pointer_delta = save_stack_pointer_delta;
3473 /* Prepare arg structure for next iteration. */
3474 for (i = 0; i < num_actuals; i++)
3476 args[i].value = 0;
3477 args[i].aligned_regs = 0;
3478 args[i].stack = 0;
3481 sbitmap_free (stored_args_map);
3483 else
3485 normal_call_insns = insns;
3487 /* Verify that we've deallocated all the stack we used. */
3488 if (! (flags & (ECF_NORETURN | ECF_LONGJMP))
3489 && old_stack_allocated != stack_pointer_delta
3490 - pending_stack_adjust)
3491 abort ();
3494 /* If something prevents making this a sibling call,
3495 zero out the sequence. */
3496 if (sibcall_failure)
3497 tail_call_insns = NULL_RTX;
3500 /* The function optimize_sibling_and_tail_recursive_calls doesn't
3501 handle CALL_PLACEHOLDERs inside other CALL_PLACEHOLDERs. This
3502 can happen if the arguments to this function call an inline
3503 function who's expansion contains another CALL_PLACEHOLDER.
3505 If there are any C_Ps in any of these sequences, replace them
3506 with their normal call. */
3508 for (insn = normal_call_insns; insn; insn = NEXT_INSN (insn))
3509 if (GET_CODE (insn) == CALL_INSN
3510 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3511 replace_call_placeholder (insn, sibcall_use_normal);
3513 for (insn = tail_call_insns; insn; insn = NEXT_INSN (insn))
3514 if (GET_CODE (insn) == CALL_INSN
3515 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3516 replace_call_placeholder (insn, sibcall_use_normal);
3518 for (insn = tail_recursion_insns; insn; insn = NEXT_INSN (insn))
3519 if (GET_CODE (insn) == CALL_INSN
3520 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
3521 replace_call_placeholder (insn, sibcall_use_normal);
3523 /* If this was a potential tail recursion site, then emit a
3524 CALL_PLACEHOLDER with the normal and the tail recursion streams.
3525 One of them will be selected later. */
3526 if (tail_recursion_insns || tail_call_insns)
3528 /* The tail recursion label must be kept around. We could expose
3529 its use in the CALL_PLACEHOLDER, but that creates unwanted edges
3530 and makes determining true tail recursion sites difficult.
3532 So we set LABEL_PRESERVE_P here, then clear it when we select
3533 one of the call sequences after rtl generation is complete. */
3534 if (tail_recursion_insns)
3535 LABEL_PRESERVE_P (tail_recursion_label) = 1;
3536 emit_call_insn (gen_rtx_CALL_PLACEHOLDER (VOIDmode, normal_call_insns,
3537 tail_call_insns,
3538 tail_recursion_insns,
3539 tail_recursion_label));
3541 else
3542 emit_insn (normal_call_insns);
3544 currently_expanding_call--;
3546 /* If this function returns with the stack pointer depressed, ensure
3547 this block saves and restores the stack pointer, show it was
3548 changed, and adjust for any outgoing arg space. */
3549 if (flags & ECF_SP_DEPRESSED)
3551 clear_pending_stack_adjust ();
3552 emit_insn (gen_rtx (CLOBBER, VOIDmode, stack_pointer_rtx));
3553 emit_move_insn (virtual_stack_dynamic_rtx, stack_pointer_rtx);
3554 save_stack_pointer ();
3557 return target;
3560 /* Traverse an argument list in VALUES and expand all complex
3561 arguments into their components. */
3562 tree
3563 split_complex_values (tree values)
3565 tree p;
3567 values = copy_list (values);
3569 for (p = values; p; p = TREE_CHAIN (p))
3571 tree complex_value = TREE_VALUE (p);
3572 tree complex_type;
3574 complex_type = TREE_TYPE (complex_value);
3575 if (!complex_type)
3576 continue;
3578 if (TREE_CODE (complex_type) == COMPLEX_TYPE)
3580 tree subtype;
3581 tree real, imag, next;
3583 subtype = TREE_TYPE (complex_type);
3584 complex_value = save_expr (complex_value);
3585 real = build1 (REALPART_EXPR, subtype, complex_value);
3586 imag = build1 (IMAGPART_EXPR, subtype, complex_value);
3588 TREE_VALUE (p) = real;
3589 next = TREE_CHAIN (p);
3590 imag = build_tree_list (NULL_TREE, imag);
3591 TREE_CHAIN (p) = imag;
3592 TREE_CHAIN (imag) = next;
3594 /* Skip the newly created node. */
3595 p = TREE_CHAIN (p);
3599 return values;
3602 /* Traverse a list of TYPES and expand all complex types into their
3603 components. */
3604 tree
3605 split_complex_types (tree types)
3607 tree p;
3609 types = copy_list (types);
3611 for (p = types; p; p = TREE_CHAIN (p))
3613 tree complex_type = TREE_VALUE (p);
3615 if (TREE_CODE (complex_type) == COMPLEX_TYPE)
3617 tree next, imag;
3619 /* Rewrite complex type with component type. */
3620 TREE_VALUE (p) = TREE_TYPE (complex_type);
3621 next = TREE_CHAIN (p);
3623 /* Add another component type for the imaginary part. */
3624 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
3625 TREE_CHAIN (p) = imag;
3626 TREE_CHAIN (imag) = next;
3628 /* Skip the newly created node. */
3629 p = TREE_CHAIN (p);
3633 return types;
3636 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3637 The RETVAL parameter specifies whether return value needs to be saved, other
3638 parameters are documented in the emit_library_call function below. */
3640 static rtx
3641 emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
3642 enum libcall_type fn_type,
3643 enum machine_mode outmode, int nargs, va_list p)
3645 /* Total size in bytes of all the stack-parms scanned so far. */
3646 struct args_size args_size;
3647 /* Size of arguments before any adjustments (such as rounding). */
3648 struct args_size original_args_size;
3649 int argnum;
3650 rtx fun;
3651 int inc;
3652 int count;
3653 rtx argblock = 0;
3654 CUMULATIVE_ARGS args_so_far;
3655 struct arg
3657 rtx value;
3658 enum machine_mode mode;
3659 rtx reg;
3660 int partial;
3661 struct locate_and_pad_arg_data locate;
3662 rtx save_area;
3664 struct arg *argvec;
3665 int old_inhibit_defer_pop = inhibit_defer_pop;
3666 rtx call_fusage = 0;
3667 rtx mem_value = 0;
3668 rtx valreg;
3669 int pcc_struct_value = 0;
3670 int struct_value_size = 0;
3671 int flags;
3672 int reg_parm_stack_space = 0;
3673 int needed;
3674 rtx before_call;
3675 tree tfom; /* type_for_mode (outmode, 0) */
3677 #ifdef REG_PARM_STACK_SPACE
3678 /* Define the boundary of the register parm stack space that needs to be
3679 save, if any. */
3680 int low_to_save, high_to_save;
3681 rtx save_area = 0; /* Place that it is saved. */
3682 #endif
3684 /* Size of the stack reserved for parameter registers. */
3685 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3686 char *initial_stack_usage_map = stack_usage_map;
3688 rtx struct_value = targetm.calls.struct_value_rtx (0, 0);
3690 #ifdef REG_PARM_STACK_SPACE
3691 #ifdef MAYBE_REG_PARM_STACK_SPACE
3692 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
3693 #else
3694 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3695 #endif
3696 #endif
3698 /* By default, library functions can not throw. */
3699 flags = ECF_NOTHROW;
3701 switch (fn_type)
3703 case LCT_NORMAL:
3704 break;
3705 case LCT_CONST:
3706 flags |= ECF_CONST;
3707 break;
3708 case LCT_PURE:
3709 flags |= ECF_PURE;
3710 break;
3711 case LCT_CONST_MAKE_BLOCK:
3712 flags |= ECF_CONST | ECF_LIBCALL_BLOCK;
3713 break;
3714 case LCT_PURE_MAKE_BLOCK:
3715 flags |= ECF_PURE | ECF_LIBCALL_BLOCK;
3716 break;
3717 case LCT_NORETURN:
3718 flags |= ECF_NORETURN;
3719 break;
3720 case LCT_THROW:
3721 flags = ECF_NORETURN;
3722 break;
3723 case LCT_ALWAYS_RETURN:
3724 flags = ECF_ALWAYS_RETURN;
3725 break;
3726 case LCT_RETURNS_TWICE:
3727 flags = ECF_RETURNS_TWICE;
3728 break;
3730 fun = orgfun;
3732 /* Ensure current function's preferred stack boundary is at least
3733 what we need. */
3734 if (cfun->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3735 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3737 /* If this kind of value comes back in memory,
3738 decide where in memory it should come back. */
3739 if (outmode != VOIDmode)
3741 tfom = (*lang_hooks.types.type_for_mode) (outmode, 0);
3742 if (aggregate_value_p (tfom, 0))
3744 #ifdef PCC_STATIC_STRUCT_RETURN
3745 rtx pointer_reg
3746 = hard_function_value (build_pointer_type (tfom), 0, 0);
3747 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3748 pcc_struct_value = 1;
3749 if (value == 0)
3750 value = gen_reg_rtx (outmode);
3751 #else /* not PCC_STATIC_STRUCT_RETURN */
3752 struct_value_size = GET_MODE_SIZE (outmode);
3753 if (value != 0 && GET_CODE (value) == MEM)
3754 mem_value = value;
3755 else
3756 mem_value = assign_temp (tfom, 0, 1, 1);
3757 #endif
3758 /* This call returns a big structure. */
3759 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3762 else
3763 tfom = void_type_node;
3765 /* ??? Unfinished: must pass the memory address as an argument. */
3767 /* Copy all the libcall-arguments out of the varargs data
3768 and into a vector ARGVEC.
3770 Compute how to pass each argument. We only support a very small subset
3771 of the full argument passing conventions to limit complexity here since
3772 library functions shouldn't have many args. */
3774 argvec = alloca ((nargs + 1) * sizeof (struct arg));
3775 memset (argvec, 0, (nargs + 1) * sizeof (struct arg));
3777 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3778 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far, outmode, fun);
3779 #else
3780 INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun, 0);
3781 #endif
3783 args_size.constant = 0;
3784 args_size.var = 0;
3786 count = 0;
3788 /* Now we are about to start emitting insns that can be deleted
3789 if a libcall is deleted. */
3790 if (flags & ECF_LIBCALL_BLOCK)
3791 start_sequence ();
3793 push_temp_slots ();
3795 /* If there's a structure value address to be passed,
3796 either pass it in the special place, or pass it as an extra argument. */
3797 if (mem_value && struct_value == 0 && ! pcc_struct_value)
3799 rtx addr = XEXP (mem_value, 0);
3800 nargs++;
3802 /* Make sure it is a reasonable operand for a move or push insn. */
3803 if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
3804 && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
3805 addr = force_operand (addr, NULL_RTX);
3807 argvec[count].value = addr;
3808 argvec[count].mode = Pmode;
3809 argvec[count].partial = 0;
3811 argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
3812 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3813 if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
3814 abort ();
3815 #endif
3817 locate_and_pad_parm (Pmode, NULL_TREE,
3818 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3820 #else
3821 argvec[count].reg != 0,
3822 #endif
3823 0, NULL_TREE, &args_size, &argvec[count].locate);
3825 if (argvec[count].reg == 0 || argvec[count].partial != 0
3826 || reg_parm_stack_space > 0)
3827 args_size.constant += argvec[count].locate.size.constant;
3829 FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree) 0, 1);
3831 count++;
3834 for (; count < nargs; count++)
3836 rtx val = va_arg (p, rtx);
3837 enum machine_mode mode = va_arg (p, enum machine_mode);
3839 /* We cannot convert the arg value to the mode the library wants here;
3840 must do it earlier where we know the signedness of the arg. */
3841 if (mode == BLKmode
3842 || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
3843 abort ();
3845 /* There's no need to call protect_from_queue, because
3846 either emit_move_insn or emit_push_insn will do that. */
3848 /* Make sure it is a reasonable operand for a move or push insn. */
3849 if (GET_CODE (val) != REG && GET_CODE (val) != MEM
3850 && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
3851 val = force_operand (val, NULL_RTX);
3853 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
3854 if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
3856 rtx slot;
3857 int must_copy = 1
3858 #ifdef FUNCTION_ARG_CALLEE_COPIES
3859 && ! FUNCTION_ARG_CALLEE_COPIES (args_so_far, mode,
3860 NULL_TREE, 1)
3861 #endif
3864 /* loop.c won't look at CALL_INSN_FUNCTION_USAGE of const/pure
3865 functions, so we have to pretend this isn't such a function. */
3866 if (flags & ECF_LIBCALL_BLOCK)
3868 rtx insns = get_insns ();
3869 end_sequence ();
3870 emit_insn (insns);
3872 flags &= ~(ECF_CONST | ECF_PURE | ECF_LIBCALL_BLOCK);
3874 /* If this was a CONST function, it is now PURE since
3875 it now reads memory. */
3876 if (flags & ECF_CONST)
3878 flags &= ~ECF_CONST;
3879 flags |= ECF_PURE;
3882 if (GET_MODE (val) == MEM && ! must_copy)
3883 slot = val;
3884 else if (must_copy)
3886 slot = assign_temp ((*lang_hooks.types.type_for_mode) (mode, 0),
3887 0, 1, 1);
3888 emit_move_insn (slot, val);
3890 else
3892 tree type = (*lang_hooks.types.type_for_mode) (mode, 0);
3894 slot
3895 = gen_rtx_MEM (mode,
3896 expand_expr (build1 (ADDR_EXPR,
3897 build_pointer_type (type),
3898 make_tree (type, val)),
3899 NULL_RTX, VOIDmode, 0));
3902 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3903 gen_rtx_USE (VOIDmode, slot),
3904 call_fusage);
3905 if (must_copy)
3906 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3907 gen_rtx_CLOBBER (VOIDmode,
3908 slot),
3909 call_fusage);
3911 mode = Pmode;
3912 val = force_operand (XEXP (slot, 0), NULL_RTX);
3914 #endif
3916 argvec[count].value = val;
3917 argvec[count].mode = mode;
3919 argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
3921 #ifdef FUNCTION_ARG_PARTIAL_NREGS
3922 argvec[count].partial
3923 = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
3924 #else
3925 argvec[count].partial = 0;
3926 #endif
3928 locate_and_pad_parm (mode, NULL_TREE,
3929 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3931 #else
3932 argvec[count].reg != 0,
3933 #endif
3934 argvec[count].partial,
3935 NULL_TREE, &args_size, &argvec[count].locate);
3937 if (argvec[count].locate.size.var)
3938 abort ();
3940 if (argvec[count].reg == 0 || argvec[count].partial != 0
3941 || reg_parm_stack_space > 0)
3942 args_size.constant += argvec[count].locate.size.constant;
3944 FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree) 0, 1);
3947 #ifdef FINAL_REG_PARM_STACK_SPACE
3948 reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
3949 args_size.var);
3950 #endif
3951 /* If this machine requires an external definition for library
3952 functions, write one out. */
3953 assemble_external_libcall (fun);
3955 original_args_size = args_size;
3956 args_size.constant = (((args_size.constant
3957 + stack_pointer_delta
3958 + STACK_BYTES - 1)
3959 / STACK_BYTES
3960 * STACK_BYTES)
3961 - stack_pointer_delta);
3963 args_size.constant = MAX (args_size.constant,
3964 reg_parm_stack_space);
3966 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3967 args_size.constant -= reg_parm_stack_space;
3968 #endif
3970 if (args_size.constant > current_function_outgoing_args_size)
3971 current_function_outgoing_args_size = args_size.constant;
3973 if (ACCUMULATE_OUTGOING_ARGS)
3975 /* Since the stack pointer will never be pushed, it is possible for
3976 the evaluation of a parm to clobber something we have already
3977 written to the stack. Since most function calls on RISC machines
3978 do not use the stack, this is uncommon, but must work correctly.
3980 Therefore, we save any area of the stack that was already written
3981 and that we are using. Here we set up to do this by making a new
3982 stack usage map from the old one.
3984 Another approach might be to try to reorder the argument
3985 evaluations to avoid this conflicting stack usage. */
3987 needed = args_size.constant;
3989 #ifndef OUTGOING_REG_PARM_STACK_SPACE
3990 /* Since we will be writing into the entire argument area, the
3991 map must be allocated for its entire size, not just the part that
3992 is the responsibility of the caller. */
3993 needed += reg_parm_stack_space;
3994 #endif
3996 #ifdef ARGS_GROW_DOWNWARD
3997 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3998 needed + 1);
3999 #else
4000 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
4001 needed);
4002 #endif
4003 stack_usage_map = alloca (highest_outgoing_arg_in_use);
4005 if (initial_highest_arg_in_use)
4006 memcpy (stack_usage_map, initial_stack_usage_map,
4007 initial_highest_arg_in_use);
4009 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
4010 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
4011 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
4012 needed = 0;
4014 /* We must be careful to use virtual regs before they're instantiated,
4015 and real regs afterwards. Loop optimization, for example, can create
4016 new libcalls after we've instantiated the virtual regs, and if we
4017 use virtuals anyway, they won't match the rtl patterns. */
4019 if (virtuals_instantiated)
4020 argblock = plus_constant (stack_pointer_rtx, STACK_POINTER_OFFSET);
4021 else
4022 argblock = virtual_outgoing_args_rtx;
4024 else
4026 if (!PUSH_ARGS)
4027 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
4030 /* If we push args individually in reverse order, perform stack alignment
4031 before the first push (the last arg). */
4032 if (argblock == 0 && PUSH_ARGS_REVERSED)
4033 anti_adjust_stack (GEN_INT (args_size.constant
4034 - original_args_size.constant));
4036 if (PUSH_ARGS_REVERSED)
4038 inc = -1;
4039 argnum = nargs - 1;
4041 else
4043 inc = 1;
4044 argnum = 0;
4047 #ifdef REG_PARM_STACK_SPACE
4048 if (ACCUMULATE_OUTGOING_ARGS)
4050 /* The argument list is the property of the called routine and it
4051 may clobber it. If the fixed area has been used for previous
4052 parameters, we must save and restore it. */
4053 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
4054 &low_to_save, &high_to_save);
4056 #endif
4058 /* Push the args that need to be pushed. */
4060 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4061 are to be pushed. */
4062 for (count = 0; count < nargs; count++, argnum += inc)
4064 enum machine_mode mode = argvec[argnum].mode;
4065 rtx val = argvec[argnum].value;
4066 rtx reg = argvec[argnum].reg;
4067 int partial = argvec[argnum].partial;
4068 int lower_bound = 0, upper_bound = 0, i;
4070 if (! (reg != 0 && partial == 0))
4072 if (ACCUMULATE_OUTGOING_ARGS)
4074 /* If this is being stored into a pre-allocated, fixed-size,
4075 stack area, save any previous data at that location. */
4077 #ifdef ARGS_GROW_DOWNWARD
4078 /* stack_slot is negative, but we want to index stack_usage_map
4079 with positive values. */
4080 upper_bound = -argvec[argnum].locate.offset.constant + 1;
4081 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
4082 #else
4083 lower_bound = argvec[argnum].locate.offset.constant;
4084 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
4085 #endif
4087 i = lower_bound;
4088 /* Don't worry about things in the fixed argument area;
4089 it has already been saved. */
4090 if (i < reg_parm_stack_space)
4091 i = reg_parm_stack_space;
4092 while (i < upper_bound && stack_usage_map[i] == 0)
4093 i++;
4095 if (i < upper_bound)
4097 /* We need to make a save area. */
4098 unsigned int size
4099 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
4100 enum machine_mode save_mode
4101 = mode_for_size (size, MODE_INT, 1);
4102 rtx adr
4103 = plus_constant (argblock,
4104 argvec[argnum].locate.offset.constant);
4105 rtx stack_area
4106 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
4108 if (save_mode == BLKmode)
4110 argvec[argnum].save_area
4111 = assign_stack_temp (BLKmode,
4112 argvec[argnum].locate.size.constant,
4115 emit_block_move (validize_mem (argvec[argnum].save_area),
4116 stack_area,
4117 GEN_INT (argvec[argnum].locate.size.constant),
4118 BLOCK_OP_CALL_PARM);
4120 else
4122 argvec[argnum].save_area = gen_reg_rtx (save_mode);
4124 emit_move_insn (argvec[argnum].save_area, stack_area);
4129 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, PARM_BOUNDARY,
4130 partial, reg, 0, argblock,
4131 GEN_INT (argvec[argnum].locate.offset.constant),
4132 reg_parm_stack_space,
4133 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad));
4135 /* Now mark the segment we just used. */
4136 if (ACCUMULATE_OUTGOING_ARGS)
4137 for (i = lower_bound; i < upper_bound; i++)
4138 stack_usage_map[i] = 1;
4140 NO_DEFER_POP;
4144 /* If we pushed args in forward order, perform stack alignment
4145 after pushing the last arg. */
4146 if (argblock == 0 && !PUSH_ARGS_REVERSED)
4147 anti_adjust_stack (GEN_INT (args_size.constant
4148 - original_args_size.constant));
4150 if (PUSH_ARGS_REVERSED)
4151 argnum = nargs - 1;
4152 else
4153 argnum = 0;
4155 fun = prepare_call_address (fun, NULL_TREE, &call_fusage, 0, 0);
4157 /* Now load any reg parms into their regs. */
4159 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4160 are to be pushed. */
4161 for (count = 0; count < nargs; count++, argnum += inc)
4163 rtx val = argvec[argnum].value;
4164 rtx reg = argvec[argnum].reg;
4165 int partial = argvec[argnum].partial;
4167 /* Handle calls that pass values in multiple non-contiguous
4168 locations. The PA64 has examples of this for library calls. */
4169 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4170 emit_group_load (reg, val, NULL_TREE, GET_MODE_SIZE (GET_MODE (val)));
4171 else if (reg != 0 && partial == 0)
4172 emit_move_insn (reg, val);
4174 NO_DEFER_POP;
4177 /* Any regs containing parms remain in use through the call. */
4178 for (count = 0; count < nargs; count++)
4180 rtx reg = argvec[count].reg;
4181 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4182 use_group_regs (&call_fusage, reg);
4183 else if (reg != 0)
4184 use_reg (&call_fusage, reg);
4187 /* Pass the function the address in which to return a structure value. */
4188 if (mem_value != 0 && struct_value != 0 && ! pcc_struct_value)
4190 emit_move_insn (struct_value,
4191 force_reg (Pmode,
4192 force_operand (XEXP (mem_value, 0),
4193 NULL_RTX)));
4194 if (GET_CODE (struct_value) == REG)
4195 use_reg (&call_fusage, struct_value);
4198 /* Don't allow popping to be deferred, since then
4199 cse'ing of library calls could delete a call and leave the pop. */
4200 NO_DEFER_POP;
4201 valreg = (mem_value == 0 && outmode != VOIDmode
4202 ? hard_libcall_value (outmode) : NULL_RTX);
4204 /* Stack must be properly aligned now. */
4205 if (stack_pointer_delta & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1))
4206 abort ();
4208 before_call = get_last_insn ();
4210 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4211 will set inhibit_defer_pop to that value. */
4212 /* The return type is needed to decide how many bytes the function pops.
4213 Signedness plays no role in that, so for simplicity, we pretend it's
4214 always signed. We also assume that the list of arguments passed has
4215 no impact, so we pretend it is unknown. */
4217 emit_call_1 (fun,
4218 get_identifier (XSTR (orgfun, 0)),
4219 build_function_type (tfom, NULL_TREE),
4220 original_args_size.constant, args_size.constant,
4221 struct_value_size,
4222 FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
4223 valreg,
4224 old_inhibit_defer_pop + 1, call_fusage, flags, & args_so_far);
4226 /* For calls to `setjmp', etc., inform flow.c it should complain
4227 if nonvolatile values are live. For functions that cannot return,
4228 inform flow that control does not fall through. */
4230 if (flags & (ECF_NORETURN | ECF_LONGJMP))
4232 /* The barrier note must be emitted
4233 immediately after the CALL_INSN. Some ports emit more than
4234 just a CALL_INSN above, so we must search for it here. */
4236 rtx last = get_last_insn ();
4237 while (GET_CODE (last) != CALL_INSN)
4239 last = PREV_INSN (last);
4240 /* There was no CALL_INSN? */
4241 if (last == before_call)
4242 abort ();
4245 emit_barrier_after (last);
4248 /* Now restore inhibit_defer_pop to its actual original value. */
4249 OK_DEFER_POP;
4251 /* If call is cse'able, make appropriate pair of reg-notes around it.
4252 Test valreg so we don't crash; may safely ignore `const'
4253 if return type is void. Disable for PARALLEL return values, because
4254 we have no way to move such values into a pseudo register. */
4255 if (flags & ECF_LIBCALL_BLOCK)
4257 rtx insns;
4259 if (valreg == 0)
4261 insns = get_insns ();
4262 end_sequence ();
4263 emit_insn (insns);
4265 else
4267 rtx note = 0;
4268 rtx temp;
4269 int i;
4271 if (GET_CODE (valreg) == PARALLEL)
4273 temp = gen_reg_rtx (outmode);
4274 emit_group_store (temp, valreg, NULL_TREE,
4275 GET_MODE_SIZE (outmode));
4276 valreg = temp;
4279 temp = gen_reg_rtx (GET_MODE (valreg));
4281 /* Construct an "equal form" for the value which mentions all the
4282 arguments in order as well as the function name. */
4283 for (i = 0; i < nargs; i++)
4284 note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
4285 note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
4287 insns = get_insns ();
4288 end_sequence ();
4290 if (flags & ECF_PURE)
4291 note = gen_rtx_EXPR_LIST (VOIDmode,
4292 gen_rtx_USE (VOIDmode,
4293 gen_rtx_MEM (BLKmode,
4294 gen_rtx_SCRATCH (VOIDmode))),
4295 note);
4297 emit_libcall_block (insns, temp, valreg, note);
4299 valreg = temp;
4302 pop_temp_slots ();
4304 /* Copy the value to the right place. */
4305 if (outmode != VOIDmode && retval)
4307 if (mem_value)
4309 if (value == 0)
4310 value = mem_value;
4311 if (value != mem_value)
4312 emit_move_insn (value, mem_value);
4314 else if (GET_CODE (valreg) == PARALLEL)
4316 if (value == 0)
4317 value = gen_reg_rtx (outmode);
4318 emit_group_store (value, valreg, NULL_TREE, GET_MODE_SIZE (outmode));
4320 else if (value != 0)
4321 emit_move_insn (value, valreg);
4322 else
4323 value = valreg;
4326 if (ACCUMULATE_OUTGOING_ARGS)
4328 #ifdef REG_PARM_STACK_SPACE
4329 if (save_area)
4330 restore_fixed_argument_area (save_area, argblock,
4331 high_to_save, low_to_save);
4332 #endif
4334 /* If we saved any argument areas, restore them. */
4335 for (count = 0; count < nargs; count++)
4336 if (argvec[count].save_area)
4338 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4339 rtx adr = plus_constant (argblock,
4340 argvec[count].locate.offset.constant);
4341 rtx stack_area = gen_rtx_MEM (save_mode,
4342 memory_address (save_mode, adr));
4344 if (save_mode == BLKmode)
4345 emit_block_move (stack_area,
4346 validize_mem (argvec[count].save_area),
4347 GEN_INT (argvec[count].locate.size.constant),
4348 BLOCK_OP_CALL_PARM);
4349 else
4350 emit_move_insn (stack_area, argvec[count].save_area);
4353 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4354 stack_usage_map = initial_stack_usage_map;
4357 return value;
4361 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4362 (emitting the queue unless NO_QUEUE is nonzero),
4363 for a value of mode OUTMODE,
4364 with NARGS different arguments, passed as alternating rtx values
4365 and machine_modes to convert them to.
4366 The rtx values should have been passed through protect_from_queue already.
4368 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for `const'
4369 calls, LCT_PURE for `pure' calls, LCT_CONST_MAKE_BLOCK for `const' calls
4370 which should be enclosed in REG_LIBCALL/REG_RETVAL notes,
4371 LCT_PURE_MAKE_BLOCK for `purep' calls which should be enclosed in
4372 REG_LIBCALL/REG_RETVAL notes with extra (use (memory (scratch)),
4373 or other LCT_ value for other types of library calls. */
4375 void
4376 emit_library_call (rtx orgfun, enum libcall_type fn_type,
4377 enum machine_mode outmode, int nargs, ...)
4379 va_list p;
4381 va_start (p, nargs);
4382 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4383 va_end (p);
4386 /* Like emit_library_call except that an extra argument, VALUE,
4387 comes second and says where to store the result.
4388 (If VALUE is zero, this function chooses a convenient way
4389 to return the value.
4391 This function returns an rtx for where the value is to be found.
4392 If VALUE is nonzero, VALUE is returned. */
4395 emit_library_call_value (rtx orgfun, rtx value,
4396 enum libcall_type fn_type,
4397 enum machine_mode outmode, int nargs, ...)
4399 rtx result;
4400 va_list p;
4402 va_start (p, nargs);
4403 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4404 nargs, p);
4405 va_end (p);
4407 return result;
4410 /* Store a single argument for a function call
4411 into the register or memory area where it must be passed.
4412 *ARG describes the argument value and where to pass it.
4414 ARGBLOCK is the address of the stack-block for all the arguments,
4415 or 0 on a machine where arguments are pushed individually.
4417 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4418 so must be careful about how the stack is used.
4420 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4421 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4422 that we need not worry about saving and restoring the stack.
4424 FNDECL is the declaration of the function we are calling.
4426 Return nonzero if this arg should cause sibcall failure,
4427 zero otherwise. */
4429 static int
4430 store_one_arg (struct arg_data *arg, rtx argblock, int flags,
4431 int variable_size ATTRIBUTE_UNUSED, int reg_parm_stack_space)
4433 tree pval = arg->tree_value;
4434 rtx reg = 0;
4435 int partial = 0;
4436 int used = 0;
4437 int i, lower_bound = 0, upper_bound = 0;
4438 int sibcall_failure = 0;
4440 if (TREE_CODE (pval) == ERROR_MARK)
4441 return 1;
4443 /* Push a new temporary level for any temporaries we make for
4444 this argument. */
4445 push_temp_slots ();
4447 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4449 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4450 save any previous data at that location. */
4451 if (argblock && ! variable_size && arg->stack)
4453 #ifdef ARGS_GROW_DOWNWARD
4454 /* stack_slot is negative, but we want to index stack_usage_map
4455 with positive values. */
4456 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4457 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4458 else
4459 upper_bound = 0;
4461 lower_bound = upper_bound - arg->locate.size.constant;
4462 #else
4463 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4464 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4465 else
4466 lower_bound = 0;
4468 upper_bound = lower_bound + arg->locate.size.constant;
4469 #endif
4471 i = lower_bound;
4472 /* Don't worry about things in the fixed argument area;
4473 it has already been saved. */
4474 if (i < reg_parm_stack_space)
4475 i = reg_parm_stack_space;
4476 while (i < upper_bound && stack_usage_map[i] == 0)
4477 i++;
4479 if (i < upper_bound)
4481 /* We need to make a save area. */
4482 unsigned int size = arg->locate.size.constant * BITS_PER_UNIT;
4483 enum machine_mode save_mode = mode_for_size (size, MODE_INT, 1);
4484 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
4485 rtx stack_area = gen_rtx_MEM (save_mode, adr);
4487 if (save_mode == BLKmode)
4489 tree ot = TREE_TYPE (arg->tree_value);
4490 tree nt = build_qualified_type (ot, (TYPE_QUALS (ot)
4491 | TYPE_QUAL_CONST));
4493 arg->save_area = assign_temp (nt, 0, 1, 1);
4494 preserve_temp_slots (arg->save_area);
4495 emit_block_move (validize_mem (arg->save_area), stack_area,
4496 expr_size (arg->tree_value),
4497 BLOCK_OP_CALL_PARM);
4499 else
4501 arg->save_area = gen_reg_rtx (save_mode);
4502 emit_move_insn (arg->save_area, stack_area);
4508 /* If this isn't going to be placed on both the stack and in registers,
4509 set up the register and number of words. */
4510 if (! arg->pass_on_stack)
4512 if (flags & ECF_SIBCALL)
4513 reg = arg->tail_call_reg;
4514 else
4515 reg = arg->reg;
4516 partial = arg->partial;
4519 if (reg != 0 && partial == 0)
4520 /* Being passed entirely in a register. We shouldn't be called in
4521 this case. */
4522 abort ();
4524 /* If this arg needs special alignment, don't load the registers
4525 here. */
4526 if (arg->n_aligned_regs != 0)
4527 reg = 0;
4529 /* If this is being passed partially in a register, we can't evaluate
4530 it directly into its stack slot. Otherwise, we can. */
4531 if (arg->value == 0)
4533 /* stack_arg_under_construction is nonzero if a function argument is
4534 being evaluated directly into the outgoing argument list and
4535 expand_call must take special action to preserve the argument list
4536 if it is called recursively.
4538 For scalar function arguments stack_usage_map is sufficient to
4539 determine which stack slots must be saved and restored. Scalar
4540 arguments in general have pass_on_stack == 0.
4542 If this argument is initialized by a function which takes the
4543 address of the argument (a C++ constructor or a C function
4544 returning a BLKmode structure), then stack_usage_map is
4545 insufficient and expand_call must push the stack around the
4546 function call. Such arguments have pass_on_stack == 1.
4548 Note that it is always safe to set stack_arg_under_construction,
4549 but this generates suboptimal code if set when not needed. */
4551 if (arg->pass_on_stack)
4552 stack_arg_under_construction++;
4554 arg->value = expand_expr (pval,
4555 (partial
4556 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4557 ? NULL_RTX : arg->stack,
4558 VOIDmode, EXPAND_STACK_PARM);
4560 /* If we are promoting object (or for any other reason) the mode
4561 doesn't agree, convert the mode. */
4563 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4564 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4565 arg->value, arg->unsignedp);
4567 if (arg->pass_on_stack)
4568 stack_arg_under_construction--;
4571 /* Don't allow anything left on stack from computation
4572 of argument to alloca. */
4573 if (flags & ECF_MAY_BE_ALLOCA)
4574 do_pending_stack_adjust ();
4576 if (arg->value == arg->stack)
4577 /* If the value is already in the stack slot, we are done. */
4579 else if (arg->mode != BLKmode)
4581 int size;
4583 /* Argument is a scalar, not entirely passed in registers.
4584 (If part is passed in registers, arg->partial says how much
4585 and emit_push_insn will take care of putting it there.)
4587 Push it, and if its size is less than the
4588 amount of space allocated to it,
4589 also bump stack pointer by the additional space.
4590 Note that in C the default argument promotions
4591 will prevent such mismatches. */
4593 size = GET_MODE_SIZE (arg->mode);
4594 /* Compute how much space the push instruction will push.
4595 On many machines, pushing a byte will advance the stack
4596 pointer by a halfword. */
4597 #ifdef PUSH_ROUNDING
4598 size = PUSH_ROUNDING (size);
4599 #endif
4600 used = size;
4602 /* Compute how much space the argument should get:
4603 round up to a multiple of the alignment for arguments. */
4604 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4605 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4606 / (PARM_BOUNDARY / BITS_PER_UNIT))
4607 * (PARM_BOUNDARY / BITS_PER_UNIT));
4609 /* This isn't already where we want it on the stack, so put it there.
4610 This can either be done with push or copy insns. */
4611 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
4612 PARM_BOUNDARY, partial, reg, used - size, argblock,
4613 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4614 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4616 /* Unless this is a partially-in-register argument, the argument is now
4617 in the stack. */
4618 if (partial == 0)
4619 arg->value = arg->stack;
4621 else
4623 /* BLKmode, at least partly to be pushed. */
4625 unsigned int parm_align;
4626 int excess;
4627 rtx size_rtx;
4629 /* Pushing a nonscalar.
4630 If part is passed in registers, PARTIAL says how much
4631 and emit_push_insn will take care of putting it there. */
4633 /* Round its size up to a multiple
4634 of the allocation unit for arguments. */
4636 if (arg->locate.size.var != 0)
4638 excess = 0;
4639 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
4641 else
4643 /* PUSH_ROUNDING has no effect on us, because
4644 emit_push_insn for BLKmode is careful to avoid it. */
4645 if (reg && GET_CODE (reg) == PARALLEL)
4647 /* Use the size of the elt to compute excess. */
4648 rtx elt = XEXP (XVECEXP (reg, 0, 0), 0);
4649 excess = (arg->locate.size.constant
4650 - int_size_in_bytes (TREE_TYPE (pval))
4651 + partial * GET_MODE_SIZE (GET_MODE (elt)));
4653 else
4654 excess = (arg->locate.size.constant
4655 - int_size_in_bytes (TREE_TYPE (pval))
4656 + partial * UNITS_PER_WORD);
4657 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
4658 NULL_RTX, TYPE_MODE (sizetype), 0);
4661 /* Some types will require stricter alignment, which will be
4662 provided for elsewhere in argument layout. */
4663 parm_align = MAX (PARM_BOUNDARY, TYPE_ALIGN (TREE_TYPE (pval)));
4665 /* When an argument is padded down, the block is aligned to
4666 PARM_BOUNDARY, but the actual argument isn't. */
4667 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4669 if (arg->locate.size.var)
4670 parm_align = BITS_PER_UNIT;
4671 else if (excess)
4673 unsigned int excess_align = (excess & -excess) * BITS_PER_UNIT;
4674 parm_align = MIN (parm_align, excess_align);
4678 if ((flags & ECF_SIBCALL) && GET_CODE (arg->value) == MEM)
4680 /* emit_push_insn might not work properly if arg->value and
4681 argblock + arg->locate.offset areas overlap. */
4682 rtx x = arg->value;
4683 int i = 0;
4685 if (XEXP (x, 0) == current_function_internal_arg_pointer
4686 || (GET_CODE (XEXP (x, 0)) == PLUS
4687 && XEXP (XEXP (x, 0), 0) ==
4688 current_function_internal_arg_pointer
4689 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT))
4691 if (XEXP (x, 0) != current_function_internal_arg_pointer)
4692 i = INTVAL (XEXP (XEXP (x, 0), 1));
4694 /* expand_call should ensure this. */
4695 if (arg->locate.offset.var || GET_CODE (size_rtx) != CONST_INT)
4696 abort ();
4698 if (arg->locate.offset.constant > i)
4700 if (arg->locate.offset.constant < i + INTVAL (size_rtx))
4701 sibcall_failure = 1;
4703 else if (arg->locate.offset.constant < i)
4705 if (i < arg->locate.offset.constant + INTVAL (size_rtx))
4706 sibcall_failure = 1;
4711 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4712 parm_align, partial, reg, excess, argblock,
4713 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4714 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4716 /* Unless this is a partially-in-register argument, the argument is now
4717 in the stack.
4719 ??? Unlike the case above, in which we want the actual
4720 address of the data, so that we can load it directly into a
4721 register, here we want the address of the stack slot, so that
4722 it's properly aligned for word-by-word copying or something
4723 like that. It's not clear that this is always correct. */
4724 if (partial == 0)
4725 arg->value = arg->stack_slot;
4728 /* Mark all slots this store used. */
4729 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
4730 && argblock && ! variable_size && arg->stack)
4731 for (i = lower_bound; i < upper_bound; i++)
4732 stack_usage_map[i] = 1;
4734 /* Once we have pushed something, pops can't safely
4735 be deferred during the rest of the arguments. */
4736 NO_DEFER_POP;
4738 /* ANSI doesn't require a sequence point here,
4739 but PCC has one, so this will avoid some problems. */
4740 emit_queue ();
4742 /* Free any temporary slots made in processing this argument. Show
4743 that we might have taken the address of something and pushed that
4744 as an operand. */
4745 preserve_temp_slots (NULL_RTX);
4746 free_temp_slots ();
4747 pop_temp_slots ();
4749 return sibcall_failure;
4752 /* Nonzero if we do not know how to pass TYPE solely in registers.
4753 We cannot do so in the following cases:
4755 - if the type has variable size
4756 - if the type is marked as addressable (it is required to be constructed
4757 into the stack)
4758 - if the padding and mode of the type is such that a copy into a register
4759 would put it into the wrong part of the register.
4761 Which padding can't be supported depends on the byte endianness.
4763 A value in a register is implicitly padded at the most significant end.
4764 On a big-endian machine, that is the lower end in memory.
4765 So a value padded in memory at the upper end can't go in a register.
4766 For a little-endian machine, the reverse is true. */
4768 bool
4769 default_must_pass_in_stack (enum machine_mode mode, tree type)
4771 if (!type)
4772 return false;
4774 /* If the type has variable size... */
4775 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4776 return true;
4778 /* If the type is marked as addressable (it is required
4779 to be constructed into the stack)... */
4780 if (TREE_ADDRESSABLE (type))
4781 return true;
4783 /* If the padding and mode of the type is such that a copy into
4784 a register would put it into the wrong part of the register. */
4785 if (mode == BLKmode
4786 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
4787 && (FUNCTION_ARG_PADDING (mode, type)
4788 == (BYTES_BIG_ENDIAN ? upward : downward)))
4789 return true;
4791 return false;