re PR middle-end/46500 (target.h includes tm.h)
[gcc.git] / gcc / calls.c
1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
4 2011 Free Software Foundation, Inc.
5
6 This file is part of GCC.
7
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
11 version.
12
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
21
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 "gimple.h"
29 #include "flags.h"
30 #include "expr.h"
31 #include "optabs.h"
32 #include "libfuncs.h"
33 #include "function.h"
34 #include "regs.h"
35 #include "diagnostic-core.h"
36 #include "output.h"
37 #include "tm_p.h"
38 #include "timevar.h"
39 #include "sbitmap.h"
40 #include "langhooks.h"
41 #include "target.h"
42 #include "cgraph.h"
43 #include "except.h"
44 #include "dbgcnt.h"
45 #include "tree-flow.h"
46
47 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
48 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
49
50 /* Data structure and subroutines used within expand_call. */
51
52 struct arg_data
53 {
54 /* Tree node for this argument. */
55 tree tree_value;
56 /* Mode for value; TYPE_MODE unless promoted. */
57 enum machine_mode mode;
58 /* Current RTL value for argument, or 0 if it isn't precomputed. */
59 rtx value;
60 /* Initially-compute RTL value for argument; only for const functions. */
61 rtx initial_value;
62 /* Register to pass this argument in, 0 if passed on stack, or an
63 PARALLEL if the arg is to be copied into multiple non-contiguous
64 registers. */
65 rtx reg;
66 /* Register to pass this argument in when generating tail call sequence.
67 This is not the same register as for normal calls on machines with
68 register windows. */
69 rtx tail_call_reg;
70 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
71 form for emit_group_move. */
72 rtx parallel_value;
73 /* If REG was promoted from the actual mode of the argument expression,
74 indicates whether the promotion is sign- or zero-extended. */
75 int unsignedp;
76 /* Number of bytes to put in registers. 0 means put the whole arg
77 in registers. Also 0 if not passed in registers. */
78 int partial;
79 /* Nonzero if argument must be passed on stack.
80 Note that some arguments may be passed on the stack
81 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
82 pass_on_stack identifies arguments that *cannot* go in registers. */
83 int pass_on_stack;
84 /* Some fields packaged up for locate_and_pad_parm. */
85 struct locate_and_pad_arg_data locate;
86 /* Location on the stack at which parameter should be stored. The store
87 has already been done if STACK == VALUE. */
88 rtx stack;
89 /* Location on the stack of the start of this argument slot. This can
90 differ from STACK if this arg pads downward. This location is known
91 to be aligned to TARGET_FUNCTION_ARG_BOUNDARY. */
92 rtx stack_slot;
93 /* Place that this stack area has been saved, if needed. */
94 rtx save_area;
95 /* If an argument's alignment does not permit direct copying into registers,
96 copy in smaller-sized pieces into pseudos. These are stored in a
97 block pointed to by this field. The next field says how many
98 word-sized pseudos we made. */
99 rtx *aligned_regs;
100 int n_aligned_regs;
101 };
102
103 /* A vector of one char per byte of stack space. A byte if nonzero if
104 the corresponding stack location has been used.
105 This vector is used to prevent a function call within an argument from
106 clobbering any stack already set up. */
107 static char *stack_usage_map;
108
109 /* Size of STACK_USAGE_MAP. */
110 static int highest_outgoing_arg_in_use;
111
112 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
113 stack location's tail call argument has been already stored into the stack.
114 This bitmap is used to prevent sibling call optimization if function tries
115 to use parent's incoming argument slots when they have been already
116 overwritten with tail call arguments. */
117 static sbitmap stored_args_map;
118
119 /* stack_arg_under_construction is nonzero when an argument may be
120 initialized with a constructor call (including a C function that
121 returns a BLKmode struct) and expand_call must take special action
122 to make sure the object being constructed does not overlap the
123 argument list for the constructor call. */
124 static int stack_arg_under_construction;
125
126 static void emit_call_1 (rtx, tree, tree, tree, HOST_WIDE_INT, HOST_WIDE_INT,
127 HOST_WIDE_INT, rtx, rtx, int, rtx, int,
128 cumulative_args_t);
129 static void precompute_register_parameters (int, struct arg_data *, int *);
130 static int store_one_arg (struct arg_data *, rtx, int, int, int);
131 static void store_unaligned_arguments_into_pseudos (struct arg_data *, int);
132 static int finalize_must_preallocate (int, int, struct arg_data *,
133 struct args_size *);
134 static void precompute_arguments (int, struct arg_data *);
135 static int compute_argument_block_size (int, struct args_size *, tree, tree, int);
136 static void initialize_argument_information (int, struct arg_data *,
137 struct args_size *, int,
138 tree, tree,
139 tree, tree, cumulative_args_t, int,
140 rtx *, int *, int *, int *,
141 bool *, bool);
142 static void compute_argument_addresses (struct arg_data *, rtx, int);
143 static rtx rtx_for_function_call (tree, tree);
144 static void load_register_parameters (struct arg_data *, int, rtx *, int,
145 int, int *);
146 static rtx emit_library_call_value_1 (int, rtx, rtx, enum libcall_type,
147 enum machine_mode, int, va_list);
148 static int special_function_p (const_tree, int);
149 static int check_sibcall_argument_overlap_1 (rtx);
150 static int check_sibcall_argument_overlap (rtx, struct arg_data *, int);
151
152 static int combine_pending_stack_adjustment_and_call (int, struct args_size *,
153 unsigned int);
154 static tree split_complex_types (tree);
155
156 #ifdef REG_PARM_STACK_SPACE
157 static rtx save_fixed_argument_area (int, rtx, int *, int *);
158 static void restore_fixed_argument_area (rtx, rtx, int, int);
159 #endif
160 \f
161 /* Force FUNEXP into a form suitable for the address of a CALL,
162 and return that as an rtx. Also load the static chain register
163 if FNDECL is a nested function.
164
165 CALL_FUSAGE points to a variable holding the prospective
166 CALL_INSN_FUNCTION_USAGE information. */
167
168 rtx
169 prepare_call_address (tree fndecl, rtx funexp, rtx static_chain_value,
170 rtx *call_fusage, int reg_parm_seen, int sibcallp)
171 {
172 /* Make a valid memory address and copy constants through pseudo-regs,
173 but not for a constant address if -fno-function-cse. */
174 if (GET_CODE (funexp) != SYMBOL_REF)
175 /* If we are using registers for parameters, force the
176 function address into a register now. */
177 funexp = ((reg_parm_seen
178 && targetm.small_register_classes_for_mode_p (FUNCTION_MODE))
179 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
180 : memory_address (FUNCTION_MODE, funexp));
181 else if (! sibcallp)
182 {
183 #ifndef NO_FUNCTION_CSE
184 if (optimize && ! flag_no_function_cse)
185 funexp = force_reg (Pmode, funexp);
186 #endif
187 }
188
189 if (static_chain_value != 0)
190 {
191 rtx chain;
192
193 gcc_assert (fndecl);
194 chain = targetm.calls.static_chain (fndecl, false);
195 static_chain_value = convert_memory_address (Pmode, static_chain_value);
196
197 emit_move_insn (chain, static_chain_value);
198 if (REG_P (chain))
199 use_reg (call_fusage, chain);
200 }
201
202 return funexp;
203 }
204
205 /* Generate instructions to call function FUNEXP,
206 and optionally pop the results.
207 The CALL_INSN is the first insn generated.
208
209 FNDECL is the declaration node of the function. This is given to the
210 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
211 its own args.
212
213 FUNTYPE is the data type of the function. This is given to the hook
214 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
215 own args. We used to allow an identifier for library functions, but
216 that doesn't work when the return type is an aggregate type and the
217 calling convention says that the pointer to this aggregate is to be
218 popped by the callee.
219
220 STACK_SIZE is the number of bytes of arguments on the stack,
221 ROUNDED_STACK_SIZE is that number rounded up to
222 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
223 both to put into the call insn and to generate explicit popping
224 code if necessary.
225
226 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
227 It is zero if this call doesn't want a structure value.
228
229 NEXT_ARG_REG is the rtx that results from executing
230 targetm.calls.function_arg (&args_so_far, VOIDmode, void_type_node, true)
231 just after all the args have had their registers assigned.
232 This could be whatever you like, but normally it is the first
233 arg-register beyond those used for args in this call,
234 or 0 if all the arg-registers are used in this call.
235 It is passed on to `gen_call' so you can put this info in the call insn.
236
237 VALREG is a hard register in which a value is returned,
238 or 0 if the call does not return a value.
239
240 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
241 the args to this call were processed.
242 We restore `inhibit_defer_pop' to that value.
243
244 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
245 denote registers used by the called function. */
246
247 static void
248 emit_call_1 (rtx funexp, tree fntree ATTRIBUTE_UNUSED, tree fndecl ATTRIBUTE_UNUSED,
249 tree funtype ATTRIBUTE_UNUSED,
250 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED,
251 HOST_WIDE_INT rounded_stack_size,
252 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED,
253 rtx next_arg_reg ATTRIBUTE_UNUSED, rtx valreg,
254 int old_inhibit_defer_pop, rtx call_fusage, int ecf_flags,
255 cumulative_args_t args_so_far ATTRIBUTE_UNUSED)
256 {
257 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
258 rtx call_insn, call, funmem;
259 int already_popped = 0;
260 HOST_WIDE_INT n_popped
261 = targetm.calls.return_pops_args (fndecl, funtype, stack_size);
262
263 #ifdef CALL_POPS_ARGS
264 n_popped += CALL_POPS_ARGS (*get_cumulative_args (args_so_far));
265 #endif
266
267 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
268 and we don't want to load it into a register as an optimization,
269 because prepare_call_address already did it if it should be done. */
270 if (GET_CODE (funexp) != SYMBOL_REF)
271 funexp = memory_address (FUNCTION_MODE, funexp);
272
273 funmem = gen_rtx_MEM (FUNCTION_MODE, funexp);
274 if (fndecl && TREE_CODE (fndecl) == FUNCTION_DECL)
275 {
276 tree t = fndecl;
277 /* Although a built-in FUNCTION_DECL and its non-__builtin
278 counterpart compare equal and get a shared mem_attrs, they
279 produce different dump output in compare-debug compilations,
280 if an entry gets garbage collected in one compilation, then
281 adds a different (but equivalent) entry, while the other
282 doesn't run the garbage collector at the same spot and then
283 shares the mem_attr with the equivalent entry. */
284 if (DECL_BUILT_IN_CLASS (t) == BUILT_IN_NORMAL
285 && built_in_decls[DECL_FUNCTION_CODE (t)])
286 t = built_in_decls[DECL_FUNCTION_CODE (t)];
287 set_mem_expr (funmem, t);
288 }
289 else if (fntree)
290 set_mem_expr (funmem, build_simple_mem_ref (CALL_EXPR_FN (fntree)));
291
292 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
293 if ((ecf_flags & ECF_SIBCALL)
294 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
295 && (n_popped > 0 || stack_size == 0))
296 {
297 rtx n_pop = GEN_INT (n_popped);
298 rtx pat;
299
300 /* If this subroutine pops its own args, record that in the call insn
301 if possible, for the sake of frame pointer elimination. */
302
303 if (valreg)
304 pat = GEN_SIBCALL_VALUE_POP (valreg, funmem, rounded_stack_size_rtx,
305 next_arg_reg, n_pop);
306 else
307 pat = GEN_SIBCALL_POP (funmem, rounded_stack_size_rtx, next_arg_reg,
308 n_pop);
309
310 emit_call_insn (pat);
311 already_popped = 1;
312 }
313 else
314 #endif
315
316 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
317 /* If the target has "call" or "call_value" insns, then prefer them
318 if no arguments are actually popped. If the target does not have
319 "call" or "call_value" insns, then we must use the popping versions
320 even if the call has no arguments to pop. */
321 #if defined (HAVE_call) && defined (HAVE_call_value)
322 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
323 && n_popped > 0)
324 #else
325 if (HAVE_call_pop && HAVE_call_value_pop)
326 #endif
327 {
328 rtx n_pop = GEN_INT (n_popped);
329 rtx pat;
330
331 /* If this subroutine pops its own args, record that in the call insn
332 if possible, for the sake of frame pointer elimination. */
333
334 if (valreg)
335 pat = GEN_CALL_VALUE_POP (valreg, funmem, rounded_stack_size_rtx,
336 next_arg_reg, n_pop);
337 else
338 pat = GEN_CALL_POP (funmem, rounded_stack_size_rtx, next_arg_reg,
339 n_pop);
340
341 emit_call_insn (pat);
342 already_popped = 1;
343 }
344 else
345 #endif
346
347 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
348 if ((ecf_flags & ECF_SIBCALL)
349 && HAVE_sibcall && HAVE_sibcall_value)
350 {
351 if (valreg)
352 emit_call_insn (GEN_SIBCALL_VALUE (valreg, funmem,
353 rounded_stack_size_rtx,
354 next_arg_reg, NULL_RTX));
355 else
356 emit_call_insn (GEN_SIBCALL (funmem, rounded_stack_size_rtx,
357 next_arg_reg,
358 GEN_INT (struct_value_size)));
359 }
360 else
361 #endif
362
363 #if defined (HAVE_call) && defined (HAVE_call_value)
364 if (HAVE_call && HAVE_call_value)
365 {
366 if (valreg)
367 emit_call_insn (GEN_CALL_VALUE (valreg, funmem, rounded_stack_size_rtx,
368 next_arg_reg, NULL_RTX));
369 else
370 emit_call_insn (GEN_CALL (funmem, rounded_stack_size_rtx, next_arg_reg,
371 GEN_INT (struct_value_size)));
372 }
373 else
374 #endif
375 gcc_unreachable ();
376
377 /* Find the call we just emitted. */
378 call_insn = last_call_insn ();
379
380 /* Some target create a fresh MEM instead of reusing the one provided
381 above. Set its MEM_EXPR. */
382 call = PATTERN (call_insn);
383 if (GET_CODE (call) == PARALLEL)
384 call = XVECEXP (call, 0, 0);
385 if (GET_CODE (call) == SET)
386 call = SET_SRC (call);
387 if (GET_CODE (call) == CALL
388 && MEM_P (XEXP (call, 0))
389 && MEM_EXPR (XEXP (call, 0)) == NULL_TREE
390 && MEM_EXPR (funmem) != NULL_TREE)
391 set_mem_expr (XEXP (call, 0), MEM_EXPR (funmem));
392
393 /* Put the register usage information there. */
394 add_function_usage_to (call_insn, call_fusage);
395
396 /* If this is a const call, then set the insn's unchanging bit. */
397 if (ecf_flags & ECF_CONST)
398 RTL_CONST_CALL_P (call_insn) = 1;
399
400 /* If this is a pure call, then set the insn's unchanging bit. */
401 if (ecf_flags & ECF_PURE)
402 RTL_PURE_CALL_P (call_insn) = 1;
403
404 /* If this is a const call, then set the insn's unchanging bit. */
405 if (ecf_flags & ECF_LOOPING_CONST_OR_PURE)
406 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn) = 1;
407
408 /* Create a nothrow REG_EH_REGION note, if needed. */
409 make_reg_eh_region_note (call_insn, ecf_flags, 0);
410
411 if (ecf_flags & ECF_NORETURN)
412 add_reg_note (call_insn, REG_NORETURN, const0_rtx);
413
414 if (ecf_flags & ECF_RETURNS_TWICE)
415 {
416 add_reg_note (call_insn, REG_SETJMP, const0_rtx);
417 cfun->calls_setjmp = 1;
418 }
419
420 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
421
422 /* Restore this now, so that we do defer pops for this call's args
423 if the context of the call as a whole permits. */
424 inhibit_defer_pop = old_inhibit_defer_pop;
425
426 if (n_popped > 0)
427 {
428 if (!already_popped)
429 CALL_INSN_FUNCTION_USAGE (call_insn)
430 = gen_rtx_EXPR_LIST (VOIDmode,
431 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
432 CALL_INSN_FUNCTION_USAGE (call_insn));
433 rounded_stack_size -= n_popped;
434 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
435 stack_pointer_delta -= n_popped;
436
437 /* If popup is needed, stack realign must use DRAP */
438 if (SUPPORTS_STACK_ALIGNMENT)
439 crtl->need_drap = true;
440 }
441
442 if (!ACCUMULATE_OUTGOING_ARGS)
443 {
444 /* If returning from the subroutine does not automatically pop the args,
445 we need an instruction to pop them sooner or later.
446 Perhaps do it now; perhaps just record how much space to pop later.
447
448 If returning from the subroutine does pop the args, indicate that the
449 stack pointer will be changed. */
450
451 if (rounded_stack_size != 0)
452 {
453 if (ecf_flags & ECF_NORETURN)
454 /* Just pretend we did the pop. */
455 stack_pointer_delta -= rounded_stack_size;
456 else if (flag_defer_pop && inhibit_defer_pop == 0
457 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
458 pending_stack_adjust += rounded_stack_size;
459 else
460 adjust_stack (rounded_stack_size_rtx);
461 }
462 }
463 /* When we accumulate outgoing args, we must avoid any stack manipulations.
464 Restore the stack pointer to its original value now. Usually
465 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
466 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
467 popping variants of functions exist as well.
468
469 ??? We may optimize similar to defer_pop above, but it is
470 probably not worthwhile.
471
472 ??? It will be worthwhile to enable combine_stack_adjustments even for
473 such machines. */
474 else if (n_popped)
475 anti_adjust_stack (GEN_INT (n_popped));
476 }
477
478 /* Determine if the function identified by NAME and FNDECL is one with
479 special properties we wish to know about.
480
481 For example, if the function might return more than one time (setjmp), then
482 set RETURNS_TWICE to a nonzero value.
483
484 Similarly set NORETURN if the function is in the longjmp family.
485
486 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
487 space from the stack such as alloca. */
488
489 static int
490 special_function_p (const_tree fndecl, int flags)
491 {
492 if (fndecl && DECL_NAME (fndecl)
493 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
494 /* Exclude functions not at the file scope, or not `extern',
495 since they are not the magic functions we would otherwise
496 think they are.
497 FIXME: this should be handled with attributes, not with this
498 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
499 because you can declare fork() inside a function if you
500 wish. */
501 && (DECL_CONTEXT (fndecl) == NULL_TREE
502 || TREE_CODE (DECL_CONTEXT (fndecl)) == TRANSLATION_UNIT_DECL)
503 && TREE_PUBLIC (fndecl))
504 {
505 const char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
506 const char *tname = name;
507
508 /* We assume that alloca will always be called by name. It
509 makes no sense to pass it as a pointer-to-function to
510 anything that does not understand its behavior. */
511 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
512 && name[0] == 'a'
513 && ! strcmp (name, "alloca"))
514 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
515 && name[0] == '_'
516 && ! strcmp (name, "__builtin_alloca"))))
517 flags |= ECF_MAY_BE_ALLOCA;
518
519 /* Disregard prefix _, __, __x or __builtin_. */
520 if (name[0] == '_')
521 {
522 if (name[1] == '_'
523 && name[2] == 'b'
524 && !strncmp (name + 3, "uiltin_", 7))
525 tname += 10;
526 else if (name[1] == '_' && name[2] == 'x')
527 tname += 3;
528 else if (name[1] == '_')
529 tname += 2;
530 else
531 tname += 1;
532 }
533
534 if (tname[0] == 's')
535 {
536 if ((tname[1] == 'e'
537 && (! strcmp (tname, "setjmp")
538 || ! strcmp (tname, "setjmp_syscall")))
539 || (tname[1] == 'i'
540 && ! strcmp (tname, "sigsetjmp"))
541 || (tname[1] == 'a'
542 && ! strcmp (tname, "savectx")))
543 flags |= ECF_RETURNS_TWICE;
544
545 if (tname[1] == 'i'
546 && ! strcmp (tname, "siglongjmp"))
547 flags |= ECF_NORETURN;
548 }
549 else if ((tname[0] == 'q' && tname[1] == 's'
550 && ! strcmp (tname, "qsetjmp"))
551 || (tname[0] == 'v' && tname[1] == 'f'
552 && ! strcmp (tname, "vfork"))
553 || (tname[0] == 'g' && tname[1] == 'e'
554 && !strcmp (tname, "getcontext")))
555 flags |= ECF_RETURNS_TWICE;
556
557 else if (tname[0] == 'l' && tname[1] == 'o'
558 && ! strcmp (tname, "longjmp"))
559 flags |= ECF_NORETURN;
560 }
561
562 return flags;
563 }
564
565 /* Return nonzero when FNDECL represents a call to setjmp. */
566
567 int
568 setjmp_call_p (const_tree fndecl)
569 {
570 if (DECL_IS_RETURNS_TWICE (fndecl))
571 return ECF_RETURNS_TWICE;
572 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
573 }
574
575
576 /* Return true if STMT is an alloca call. */
577
578 bool
579 gimple_alloca_call_p (const_gimple stmt)
580 {
581 tree fndecl;
582
583 if (!is_gimple_call (stmt))
584 return false;
585
586 fndecl = gimple_call_fndecl (stmt);
587 if (fndecl && (special_function_p (fndecl, 0) & ECF_MAY_BE_ALLOCA))
588 return true;
589
590 return false;
591 }
592
593 /* Return true when exp contains alloca call. */
594
595 bool
596 alloca_call_p (const_tree exp)
597 {
598 if (TREE_CODE (exp) == CALL_EXPR
599 && TREE_CODE (CALL_EXPR_FN (exp)) == ADDR_EXPR
600 && (TREE_CODE (TREE_OPERAND (CALL_EXPR_FN (exp), 0)) == FUNCTION_DECL)
601 && (special_function_p (TREE_OPERAND (CALL_EXPR_FN (exp), 0), 0)
602 & ECF_MAY_BE_ALLOCA))
603 return true;
604 return false;
605 }
606
607 /* Detect flags (function attributes) from the function decl or type node. */
608
609 int
610 flags_from_decl_or_type (const_tree exp)
611 {
612 int flags = 0;
613
614 if (DECL_P (exp))
615 {
616 /* The function exp may have the `malloc' attribute. */
617 if (DECL_IS_MALLOC (exp))
618 flags |= ECF_MALLOC;
619
620 /* The function exp may have the `returns_twice' attribute. */
621 if (DECL_IS_RETURNS_TWICE (exp))
622 flags |= ECF_RETURNS_TWICE;
623
624 /* Process the pure and const attributes. */
625 if (TREE_READONLY (exp))
626 flags |= ECF_CONST;
627 if (DECL_PURE_P (exp))
628 flags |= ECF_PURE;
629 if (DECL_LOOPING_CONST_OR_PURE_P (exp))
630 flags |= ECF_LOOPING_CONST_OR_PURE;
631
632 if (DECL_IS_NOVOPS (exp))
633 flags |= ECF_NOVOPS;
634 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp)))
635 flags |= ECF_LEAF;
636
637 if (TREE_NOTHROW (exp))
638 flags |= ECF_NOTHROW;
639
640 flags = special_function_p (exp, flags);
641 }
642 else if (TYPE_P (exp) && TYPE_READONLY (exp))
643 flags |= ECF_CONST;
644
645 if (TREE_THIS_VOLATILE (exp))
646 {
647 flags |= ECF_NORETURN;
648 if (flags & (ECF_CONST|ECF_PURE))
649 flags |= ECF_LOOPING_CONST_OR_PURE;
650 }
651
652 return flags;
653 }
654
655 /* Detect flags from a CALL_EXPR. */
656
657 int
658 call_expr_flags (const_tree t)
659 {
660 int flags;
661 tree decl = get_callee_fndecl (t);
662
663 if (decl)
664 flags = flags_from_decl_or_type (decl);
665 else
666 {
667 t = TREE_TYPE (CALL_EXPR_FN (t));
668 if (t && TREE_CODE (t) == POINTER_TYPE)
669 flags = flags_from_decl_or_type (TREE_TYPE (t));
670 else
671 flags = 0;
672 }
673
674 return flags;
675 }
676
677 /* Precompute all register parameters as described by ARGS, storing values
678 into fields within the ARGS array.
679
680 NUM_ACTUALS indicates the total number elements in the ARGS array.
681
682 Set REG_PARM_SEEN if we encounter a register parameter. */
683
684 static void
685 precompute_register_parameters (int num_actuals, struct arg_data *args,
686 int *reg_parm_seen)
687 {
688 int i;
689
690 *reg_parm_seen = 0;
691
692 for (i = 0; i < num_actuals; i++)
693 if (args[i].reg != 0 && ! args[i].pass_on_stack)
694 {
695 *reg_parm_seen = 1;
696
697 if (args[i].value == 0)
698 {
699 push_temp_slots ();
700 args[i].value = expand_normal (args[i].tree_value);
701 preserve_temp_slots (args[i].value);
702 pop_temp_slots ();
703 }
704
705 /* If the value is a non-legitimate constant, force it into a
706 pseudo now. TLS symbols sometimes need a call to resolve. */
707 if (CONSTANT_P (args[i].value)
708 && !targetm.legitimate_constant_p (args[i].mode, args[i].value))
709 args[i].value = force_reg (args[i].mode, args[i].value);
710
711 /* If we are to promote the function arg to a wider mode,
712 do it now. */
713
714 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
715 args[i].value
716 = convert_modes (args[i].mode,
717 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
718 args[i].value, args[i].unsignedp);
719
720 /* If we're going to have to load the value by parts, pull the
721 parts into pseudos. The part extraction process can involve
722 non-trivial computation. */
723 if (GET_CODE (args[i].reg) == PARALLEL)
724 {
725 tree type = TREE_TYPE (args[i].tree_value);
726 args[i].parallel_value
727 = emit_group_load_into_temps (args[i].reg, args[i].value,
728 type, int_size_in_bytes (type));
729 }
730
731 /* If the value is expensive, and we are inside an appropriately
732 short loop, put the value into a pseudo and then put the pseudo
733 into the hard reg.
734
735 For small register classes, also do this if this call uses
736 register parameters. This is to avoid reload conflicts while
737 loading the parameters registers. */
738
739 else if ((! (REG_P (args[i].value)
740 || (GET_CODE (args[i].value) == SUBREG
741 && REG_P (SUBREG_REG (args[i].value)))))
742 && args[i].mode != BLKmode
743 && rtx_cost (args[i].value, SET, optimize_insn_for_speed_p ())
744 > COSTS_N_INSNS (1)
745 && ((*reg_parm_seen
746 && targetm.small_register_classes_for_mode_p (args[i].mode))
747 || optimize))
748 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
749 }
750 }
751
752 #ifdef REG_PARM_STACK_SPACE
753
754 /* The argument list is the property of the called routine and it
755 may clobber it. If the fixed area has been used for previous
756 parameters, we must save and restore it. */
757
758 static rtx
759 save_fixed_argument_area (int reg_parm_stack_space, rtx argblock, int *low_to_save, int *high_to_save)
760 {
761 int low;
762 int high;
763
764 /* Compute the boundary of the area that needs to be saved, if any. */
765 high = reg_parm_stack_space;
766 #ifdef ARGS_GROW_DOWNWARD
767 high += 1;
768 #endif
769 if (high > highest_outgoing_arg_in_use)
770 high = highest_outgoing_arg_in_use;
771
772 for (low = 0; low < high; low++)
773 if (stack_usage_map[low] != 0)
774 {
775 int num_to_save;
776 enum machine_mode save_mode;
777 int delta;
778 rtx stack_area;
779 rtx save_area;
780
781 while (stack_usage_map[--high] == 0)
782 ;
783
784 *low_to_save = low;
785 *high_to_save = high;
786
787 num_to_save = high - low + 1;
788 save_mode = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
789
790 /* If we don't have the required alignment, must do this
791 in BLKmode. */
792 if ((low & (MIN (GET_MODE_SIZE (save_mode),
793 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
794 save_mode = BLKmode;
795
796 #ifdef ARGS_GROW_DOWNWARD
797 delta = -high;
798 #else
799 delta = low;
800 #endif
801 stack_area = gen_rtx_MEM (save_mode,
802 memory_address (save_mode,
803 plus_constant (argblock,
804 delta)));
805
806 set_mem_align (stack_area, PARM_BOUNDARY);
807 if (save_mode == BLKmode)
808 {
809 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
810 emit_block_move (validize_mem (save_area), stack_area,
811 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
812 }
813 else
814 {
815 save_area = gen_reg_rtx (save_mode);
816 emit_move_insn (save_area, stack_area);
817 }
818
819 return save_area;
820 }
821
822 return NULL_RTX;
823 }
824
825 static void
826 restore_fixed_argument_area (rtx save_area, rtx argblock, int high_to_save, int low_to_save)
827 {
828 enum machine_mode save_mode = GET_MODE (save_area);
829 int delta;
830 rtx stack_area;
831
832 #ifdef ARGS_GROW_DOWNWARD
833 delta = -high_to_save;
834 #else
835 delta = low_to_save;
836 #endif
837 stack_area = gen_rtx_MEM (save_mode,
838 memory_address (save_mode,
839 plus_constant (argblock, delta)));
840 set_mem_align (stack_area, PARM_BOUNDARY);
841
842 if (save_mode != BLKmode)
843 emit_move_insn (stack_area, save_area);
844 else
845 emit_block_move (stack_area, validize_mem (save_area),
846 GEN_INT (high_to_save - low_to_save + 1),
847 BLOCK_OP_CALL_PARM);
848 }
849 #endif /* REG_PARM_STACK_SPACE */
850
851 /* If any elements in ARGS refer to parameters that are to be passed in
852 registers, but not in memory, and whose alignment does not permit a
853 direct copy into registers. Copy the values into a group of pseudos
854 which we will later copy into the appropriate hard registers.
855
856 Pseudos for each unaligned argument will be stored into the array
857 args[argnum].aligned_regs. The caller is responsible for deallocating
858 the aligned_regs array if it is nonzero. */
859
860 static void
861 store_unaligned_arguments_into_pseudos (struct arg_data *args, int num_actuals)
862 {
863 int i, j;
864
865 for (i = 0; i < num_actuals; i++)
866 if (args[i].reg != 0 && ! args[i].pass_on_stack
867 && args[i].mode == BLKmode
868 && MEM_P (args[i].value)
869 && (MEM_ALIGN (args[i].value)
870 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
871 {
872 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
873 int endian_correction = 0;
874
875 if (args[i].partial)
876 {
877 gcc_assert (args[i].partial % UNITS_PER_WORD == 0);
878 args[i].n_aligned_regs = args[i].partial / UNITS_PER_WORD;
879 }
880 else
881 {
882 args[i].n_aligned_regs
883 = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
884 }
885
886 args[i].aligned_regs = XNEWVEC (rtx, args[i].n_aligned_regs);
887
888 /* Structures smaller than a word are normally aligned to the
889 least significant byte. On a BYTES_BIG_ENDIAN machine,
890 this means we must skip the empty high order bytes when
891 calculating the bit offset. */
892 if (bytes < UNITS_PER_WORD
893 #ifdef BLOCK_REG_PADDING
894 && (BLOCK_REG_PADDING (args[i].mode,
895 TREE_TYPE (args[i].tree_value), 1)
896 == downward)
897 #else
898 && BYTES_BIG_ENDIAN
899 #endif
900 )
901 endian_correction = BITS_PER_WORD - bytes * BITS_PER_UNIT;
902
903 for (j = 0; j < args[i].n_aligned_regs; j++)
904 {
905 rtx reg = gen_reg_rtx (word_mode);
906 rtx word = operand_subword_force (args[i].value, j, BLKmode);
907 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
908
909 args[i].aligned_regs[j] = reg;
910 word = extract_bit_field (word, bitsize, 0, 1, false, NULL_RTX,
911 word_mode, word_mode);
912
913 /* There is no need to restrict this code to loading items
914 in TYPE_ALIGN sized hunks. The bitfield instructions can
915 load up entire word sized registers efficiently.
916
917 ??? This may not be needed anymore.
918 We use to emit a clobber here but that doesn't let later
919 passes optimize the instructions we emit. By storing 0 into
920 the register later passes know the first AND to zero out the
921 bitfield being set in the register is unnecessary. The store
922 of 0 will be deleted as will at least the first AND. */
923
924 emit_move_insn (reg, const0_rtx);
925
926 bytes -= bitsize / BITS_PER_UNIT;
927 store_bit_field (reg, bitsize, endian_correction, word_mode,
928 word);
929 }
930 }
931 }
932
933 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
934 CALL_EXPR EXP.
935
936 NUM_ACTUALS is the total number of parameters.
937
938 N_NAMED_ARGS is the total number of named arguments.
939
940 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
941 value, or null.
942
943 FNDECL is the tree code for the target of this call (if known)
944
945 ARGS_SO_FAR holds state needed by the target to know where to place
946 the next argument.
947
948 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
949 for arguments which are passed in registers.
950
951 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
952 and may be modified by this routine.
953
954 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
955 flags which may may be modified by this routine.
956
957 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
958 that requires allocation of stack space.
959
960 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
961 the thunked-to function. */
962
963 static void
964 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
965 struct arg_data *args,
966 struct args_size *args_size,
967 int n_named_args ATTRIBUTE_UNUSED,
968 tree exp, tree struct_value_addr_value,
969 tree fndecl, tree fntype,
970 cumulative_args_t args_so_far,
971 int reg_parm_stack_space,
972 rtx *old_stack_level, int *old_pending_adj,
973 int *must_preallocate, int *ecf_flags,
974 bool *may_tailcall, bool call_from_thunk_p)
975 {
976 CUMULATIVE_ARGS *args_so_far_pnt = get_cumulative_args (args_so_far);
977 location_t loc = EXPR_LOCATION (exp);
978 /* 1 if scanning parms front to back, -1 if scanning back to front. */
979 int inc;
980
981 /* Count arg position in order args appear. */
982 int argpos;
983
984 int i;
985
986 args_size->constant = 0;
987 args_size->var = 0;
988
989 /* In this loop, we consider args in the order they are written.
990 We fill up ARGS from the front or from the back if necessary
991 so that in any case the first arg to be pushed ends up at the front. */
992
993 if (PUSH_ARGS_REVERSED)
994 {
995 i = num_actuals - 1, inc = -1;
996 /* In this case, must reverse order of args
997 so that we compute and push the last arg first. */
998 }
999 else
1000 {
1001 i = 0, inc = 1;
1002 }
1003
1004 /* First fill in the actual arguments in the ARGS array, splitting
1005 complex arguments if necessary. */
1006 {
1007 int j = i;
1008 call_expr_arg_iterator iter;
1009 tree arg;
1010
1011 if (struct_value_addr_value)
1012 {
1013 args[j].tree_value = struct_value_addr_value;
1014 j += inc;
1015 }
1016 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
1017 {
1018 tree argtype = TREE_TYPE (arg);
1019 if (targetm.calls.split_complex_arg
1020 && argtype
1021 && TREE_CODE (argtype) == COMPLEX_TYPE
1022 && targetm.calls.split_complex_arg (argtype))
1023 {
1024 tree subtype = TREE_TYPE (argtype);
1025 args[j].tree_value = build1 (REALPART_EXPR, subtype, arg);
1026 j += inc;
1027 args[j].tree_value = build1 (IMAGPART_EXPR, subtype, arg);
1028 }
1029 else
1030 args[j].tree_value = arg;
1031 j += inc;
1032 }
1033 }
1034
1035 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1036 for (argpos = 0; argpos < num_actuals; i += inc, argpos++)
1037 {
1038 tree type = TREE_TYPE (args[i].tree_value);
1039 int unsignedp;
1040 enum machine_mode mode;
1041
1042 /* Replace erroneous argument with constant zero. */
1043 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1044 args[i].tree_value = integer_zero_node, type = integer_type_node;
1045
1046 /* If TYPE is a transparent union or record, pass things the way
1047 we would pass the first field of the union or record. We have
1048 already verified that the modes are the same. */
1049 if ((TREE_CODE (type) == UNION_TYPE || TREE_CODE (type) == RECORD_TYPE)
1050 && TYPE_TRANSPARENT_AGGR (type))
1051 type = TREE_TYPE (first_field (type));
1052
1053 /* Decide where to pass this arg.
1054
1055 args[i].reg is nonzero if all or part is passed in registers.
1056
1057 args[i].partial is nonzero if part but not all is passed in registers,
1058 and the exact value says how many bytes are passed in registers.
1059
1060 args[i].pass_on_stack is nonzero if the argument must at least be
1061 computed on the stack. It may then be loaded back into registers
1062 if args[i].reg is nonzero.
1063
1064 These decisions are driven by the FUNCTION_... macros and must agree
1065 with those made by function.c. */
1066
1067 /* See if this argument should be passed by invisible reference. */
1068 if (pass_by_reference (args_so_far_pnt, TYPE_MODE (type),
1069 type, argpos < n_named_args))
1070 {
1071 bool callee_copies;
1072 tree base;
1073
1074 callee_copies
1075 = reference_callee_copied (args_so_far_pnt, TYPE_MODE (type),
1076 type, argpos < n_named_args);
1077
1078 /* If we're compiling a thunk, pass through invisible references
1079 instead of making a copy. */
1080 if (call_from_thunk_p
1081 || (callee_copies
1082 && !TREE_ADDRESSABLE (type)
1083 && (base = get_base_address (args[i].tree_value))
1084 && TREE_CODE (base) != SSA_NAME
1085 && (!DECL_P (base) || MEM_P (DECL_RTL (base)))))
1086 {
1087 /* We can't use sibcalls if a callee-copied argument is
1088 stored in the current function's frame. */
1089 if (!call_from_thunk_p && DECL_P (base) && !TREE_STATIC (base))
1090 *may_tailcall = false;
1091
1092 args[i].tree_value = build_fold_addr_expr_loc (loc,
1093 args[i].tree_value);
1094 type = TREE_TYPE (args[i].tree_value);
1095
1096 if (*ecf_flags & ECF_CONST)
1097 *ecf_flags &= ~(ECF_CONST | ECF_LOOPING_CONST_OR_PURE);
1098 }
1099 else
1100 {
1101 /* We make a copy of the object and pass the address to the
1102 function being called. */
1103 rtx copy;
1104
1105 if (!COMPLETE_TYPE_P (type)
1106 || TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST
1107 || (flag_stack_check == GENERIC_STACK_CHECK
1108 && compare_tree_int (TYPE_SIZE_UNIT (type),
1109 STACK_CHECK_MAX_VAR_SIZE) > 0))
1110 {
1111 /* This is a variable-sized object. Make space on the stack
1112 for it. */
1113 rtx size_rtx = expr_size (args[i].tree_value);
1114
1115 if (*old_stack_level == 0)
1116 {
1117 emit_stack_save (SAVE_BLOCK, old_stack_level);
1118 *old_pending_adj = pending_stack_adjust;
1119 pending_stack_adjust = 0;
1120 }
1121
1122 /* We can pass TRUE as the 4th argument because we just
1123 saved the stack pointer and will restore it right after
1124 the call. */
1125 copy = allocate_dynamic_stack_space (size_rtx,
1126 TYPE_ALIGN (type),
1127 TYPE_ALIGN (type),
1128 true);
1129 copy = gen_rtx_MEM (BLKmode, copy);
1130 set_mem_attributes (copy, type, 1);
1131 }
1132 else
1133 copy = assign_temp (type, 0, 1, 0);
1134
1135 store_expr (args[i].tree_value, copy, 0, false);
1136
1137 /* Just change the const function to pure and then let
1138 the next test clear the pure based on
1139 callee_copies. */
1140 if (*ecf_flags & ECF_CONST)
1141 {
1142 *ecf_flags &= ~ECF_CONST;
1143 *ecf_flags |= ECF_PURE;
1144 }
1145
1146 if (!callee_copies && *ecf_flags & ECF_PURE)
1147 *ecf_flags &= ~(ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
1148
1149 args[i].tree_value
1150 = build_fold_addr_expr_loc (loc, make_tree (type, copy));
1151 type = TREE_TYPE (args[i].tree_value);
1152 *may_tailcall = false;
1153 }
1154 }
1155
1156 unsignedp = TYPE_UNSIGNED (type);
1157 mode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
1158 fndecl ? TREE_TYPE (fndecl) : fntype, 0);
1159
1160 args[i].unsignedp = unsignedp;
1161 args[i].mode = mode;
1162
1163 args[i].reg = targetm.calls.function_arg (args_so_far, mode, type,
1164 argpos < n_named_args);
1165
1166 /* If this is a sibling call and the machine has register windows, the
1167 register window has to be unwinded before calling the routine, so
1168 arguments have to go into the incoming registers. */
1169 if (targetm.calls.function_incoming_arg != targetm.calls.function_arg)
1170 args[i].tail_call_reg
1171 = targetm.calls.function_incoming_arg (args_so_far, mode, type,
1172 argpos < n_named_args);
1173 else
1174 args[i].tail_call_reg = args[i].reg;
1175
1176 if (args[i].reg)
1177 args[i].partial
1178 = targetm.calls.arg_partial_bytes (args_so_far, mode, type,
1179 argpos < n_named_args);
1180
1181 args[i].pass_on_stack = targetm.calls.must_pass_in_stack (mode, type);
1182
1183 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1184 it means that we are to pass this arg in the register(s) designated
1185 by the PARALLEL, but also to pass it in the stack. */
1186 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1187 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1188 args[i].pass_on_stack = 1;
1189
1190 /* If this is an addressable type, we must preallocate the stack
1191 since we must evaluate the object into its final location.
1192
1193 If this is to be passed in both registers and the stack, it is simpler
1194 to preallocate. */
1195 if (TREE_ADDRESSABLE (type)
1196 || (args[i].pass_on_stack && args[i].reg != 0))
1197 *must_preallocate = 1;
1198
1199 /* Compute the stack-size of this argument. */
1200 if (args[i].reg == 0 || args[i].partial != 0
1201 || reg_parm_stack_space > 0
1202 || args[i].pass_on_stack)
1203 locate_and_pad_parm (mode, type,
1204 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1205 1,
1206 #else
1207 args[i].reg != 0,
1208 #endif
1209 args[i].pass_on_stack ? 0 : args[i].partial,
1210 fndecl, args_size, &args[i].locate);
1211 #ifdef BLOCK_REG_PADDING
1212 else
1213 /* The argument is passed entirely in registers. See at which
1214 end it should be padded. */
1215 args[i].locate.where_pad =
1216 BLOCK_REG_PADDING (mode, type,
1217 int_size_in_bytes (type) <= UNITS_PER_WORD);
1218 #endif
1219
1220 /* Update ARGS_SIZE, the total stack space for args so far. */
1221
1222 args_size->constant += args[i].locate.size.constant;
1223 if (args[i].locate.size.var)
1224 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
1225
1226 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1227 have been used, etc. */
1228
1229 targetm.calls.function_arg_advance (args_so_far, TYPE_MODE (type),
1230 type, argpos < n_named_args);
1231 }
1232 }
1233
1234 /* Update ARGS_SIZE to contain the total size for the argument block.
1235 Return the original constant component of the argument block's size.
1236
1237 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1238 for arguments passed in registers. */
1239
1240 static int
1241 compute_argument_block_size (int reg_parm_stack_space,
1242 struct args_size *args_size,
1243 tree fndecl ATTRIBUTE_UNUSED,
1244 tree fntype ATTRIBUTE_UNUSED,
1245 int preferred_stack_boundary ATTRIBUTE_UNUSED)
1246 {
1247 int unadjusted_args_size = args_size->constant;
1248
1249 /* For accumulate outgoing args mode we don't need to align, since the frame
1250 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1251 backends from generating misaligned frame sizes. */
1252 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1253 preferred_stack_boundary = STACK_BOUNDARY;
1254
1255 /* Compute the actual size of the argument block required. The variable
1256 and constant sizes must be combined, the size may have to be rounded,
1257 and there may be a minimum required size. */
1258
1259 if (args_size->var)
1260 {
1261 args_size->var = ARGS_SIZE_TREE (*args_size);
1262 args_size->constant = 0;
1263
1264 preferred_stack_boundary /= BITS_PER_UNIT;
1265 if (preferred_stack_boundary > 1)
1266 {
1267 /* We don't handle this case yet. To handle it correctly we have
1268 to add the delta, round and subtract the delta.
1269 Currently no machine description requires this support. */
1270 gcc_assert (!(stack_pointer_delta & (preferred_stack_boundary - 1)));
1271 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1272 }
1273
1274 if (reg_parm_stack_space > 0)
1275 {
1276 args_size->var
1277 = size_binop (MAX_EXPR, args_size->var,
1278 ssize_int (reg_parm_stack_space));
1279
1280 /* The area corresponding to register parameters is not to count in
1281 the size of the block we need. So make the adjustment. */
1282 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
1283 args_size->var
1284 = size_binop (MINUS_EXPR, args_size->var,
1285 ssize_int (reg_parm_stack_space));
1286 }
1287 }
1288 else
1289 {
1290 preferred_stack_boundary /= BITS_PER_UNIT;
1291 if (preferred_stack_boundary < 1)
1292 preferred_stack_boundary = 1;
1293 args_size->constant = (((args_size->constant
1294 + stack_pointer_delta
1295 + preferred_stack_boundary - 1)
1296 / preferred_stack_boundary
1297 * preferred_stack_boundary)
1298 - stack_pointer_delta);
1299
1300 args_size->constant = MAX (args_size->constant,
1301 reg_parm_stack_space);
1302
1303 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
1304 args_size->constant -= reg_parm_stack_space;
1305 }
1306 return unadjusted_args_size;
1307 }
1308
1309 /* Precompute parameters as needed for a function call.
1310
1311 FLAGS is mask of ECF_* constants.
1312
1313 NUM_ACTUALS is the number of arguments.
1314
1315 ARGS is an array containing information for each argument; this
1316 routine fills in the INITIAL_VALUE and VALUE fields for each
1317 precomputed argument. */
1318
1319 static void
1320 precompute_arguments (int num_actuals, struct arg_data *args)
1321 {
1322 int i;
1323
1324 /* If this is a libcall, then precompute all arguments so that we do not
1325 get extraneous instructions emitted as part of the libcall sequence. */
1326
1327 /* If we preallocated the stack space, and some arguments must be passed
1328 on the stack, then we must precompute any parameter which contains a
1329 function call which will store arguments on the stack.
1330 Otherwise, evaluating the parameter may clobber previous parameters
1331 which have already been stored into the stack. (we have code to avoid
1332 such case by saving the outgoing stack arguments, but it results in
1333 worse code) */
1334 if (!ACCUMULATE_OUTGOING_ARGS)
1335 return;
1336
1337 for (i = 0; i < num_actuals; i++)
1338 {
1339 tree type;
1340 enum machine_mode mode;
1341
1342 if (TREE_CODE (args[i].tree_value) != CALL_EXPR)
1343 continue;
1344
1345 /* If this is an addressable type, we cannot pre-evaluate it. */
1346 type = TREE_TYPE (args[i].tree_value);
1347 gcc_assert (!TREE_ADDRESSABLE (type));
1348
1349 args[i].initial_value = args[i].value
1350 = expand_normal (args[i].tree_value);
1351
1352 mode = TYPE_MODE (type);
1353 if (mode != args[i].mode)
1354 {
1355 int unsignedp = args[i].unsignedp;
1356 args[i].value
1357 = convert_modes (args[i].mode, mode,
1358 args[i].value, args[i].unsignedp);
1359
1360 /* CSE will replace this only if it contains args[i].value
1361 pseudo, so convert it down to the declared mode using
1362 a SUBREG. */
1363 if (REG_P (args[i].value)
1364 && GET_MODE_CLASS (args[i].mode) == MODE_INT
1365 && promote_mode (type, mode, &unsignedp) != args[i].mode)
1366 {
1367 args[i].initial_value
1368 = gen_lowpart_SUBREG (mode, args[i].value);
1369 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1370 SUBREG_PROMOTED_UNSIGNED_SET (args[i].initial_value,
1371 args[i].unsignedp);
1372 }
1373 }
1374 }
1375 }
1376
1377 /* Given the current state of MUST_PREALLOCATE and information about
1378 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1379 compute and return the final value for MUST_PREALLOCATE. */
1380
1381 static int
1382 finalize_must_preallocate (int must_preallocate, int num_actuals,
1383 struct arg_data *args, struct args_size *args_size)
1384 {
1385 /* See if we have or want to preallocate stack space.
1386
1387 If we would have to push a partially-in-regs parm
1388 before other stack parms, preallocate stack space instead.
1389
1390 If the size of some parm is not a multiple of the required stack
1391 alignment, we must preallocate.
1392
1393 If the total size of arguments that would otherwise create a copy in
1394 a temporary (such as a CALL) is more than half the total argument list
1395 size, preallocation is faster.
1396
1397 Another reason to preallocate is if we have a machine (like the m88k)
1398 where stack alignment is required to be maintained between every
1399 pair of insns, not just when the call is made. However, we assume here
1400 that such machines either do not have push insns (and hence preallocation
1401 would occur anyway) or the problem is taken care of with
1402 PUSH_ROUNDING. */
1403
1404 if (! must_preallocate)
1405 {
1406 int partial_seen = 0;
1407 int copy_to_evaluate_size = 0;
1408 int i;
1409
1410 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1411 {
1412 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1413 partial_seen = 1;
1414 else if (partial_seen && args[i].reg == 0)
1415 must_preallocate = 1;
1416
1417 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1418 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1419 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1420 || TREE_CODE (args[i].tree_value) == COND_EXPR
1421 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1422 copy_to_evaluate_size
1423 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1424 }
1425
1426 if (copy_to_evaluate_size * 2 >= args_size->constant
1427 && args_size->constant > 0)
1428 must_preallocate = 1;
1429 }
1430 return must_preallocate;
1431 }
1432
1433 /* If we preallocated stack space, compute the address of each argument
1434 and store it into the ARGS array.
1435
1436 We need not ensure it is a valid memory address here; it will be
1437 validized when it is used.
1438
1439 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1440
1441 static void
1442 compute_argument_addresses (struct arg_data *args, rtx argblock, int num_actuals)
1443 {
1444 if (argblock)
1445 {
1446 rtx arg_reg = argblock;
1447 int i, arg_offset = 0;
1448
1449 if (GET_CODE (argblock) == PLUS)
1450 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1451
1452 for (i = 0; i < num_actuals; i++)
1453 {
1454 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
1455 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
1456 rtx addr;
1457 unsigned int align, boundary;
1458 unsigned int units_on_stack = 0;
1459 enum machine_mode partial_mode = VOIDmode;
1460
1461 /* Skip this parm if it will not be passed on the stack. */
1462 if (! args[i].pass_on_stack
1463 && args[i].reg != 0
1464 && args[i].partial == 0)
1465 continue;
1466
1467 if (CONST_INT_P (offset))
1468 addr = plus_constant (arg_reg, INTVAL (offset));
1469 else
1470 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1471
1472 addr = plus_constant (addr, arg_offset);
1473
1474 if (args[i].partial != 0)
1475 {
1476 /* Only part of the parameter is being passed on the stack.
1477 Generate a simple memory reference of the correct size. */
1478 units_on_stack = args[i].locate.size.constant;
1479 partial_mode = mode_for_size (units_on_stack * BITS_PER_UNIT,
1480 MODE_INT, 1);
1481 args[i].stack = gen_rtx_MEM (partial_mode, addr);
1482 set_mem_size (args[i].stack, GEN_INT (units_on_stack));
1483 }
1484 else
1485 {
1486 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1487 set_mem_attributes (args[i].stack,
1488 TREE_TYPE (args[i].tree_value), 1);
1489 }
1490 align = BITS_PER_UNIT;
1491 boundary = args[i].locate.boundary;
1492 if (args[i].locate.where_pad != downward)
1493 align = boundary;
1494 else if (CONST_INT_P (offset))
1495 {
1496 align = INTVAL (offset) * BITS_PER_UNIT | boundary;
1497 align = align & -align;
1498 }
1499 set_mem_align (args[i].stack, align);
1500
1501 if (CONST_INT_P (slot_offset))
1502 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1503 else
1504 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1505
1506 addr = plus_constant (addr, arg_offset);
1507
1508 if (args[i].partial != 0)
1509 {
1510 /* Only part of the parameter is being passed on the stack.
1511 Generate a simple memory reference of the correct size.
1512 */
1513 args[i].stack_slot = gen_rtx_MEM (partial_mode, addr);
1514 set_mem_size (args[i].stack_slot, GEN_INT (units_on_stack));
1515 }
1516 else
1517 {
1518 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1519 set_mem_attributes (args[i].stack_slot,
1520 TREE_TYPE (args[i].tree_value), 1);
1521 }
1522 set_mem_align (args[i].stack_slot, args[i].locate.boundary);
1523
1524 /* Function incoming arguments may overlap with sibling call
1525 outgoing arguments and we cannot allow reordering of reads
1526 from function arguments with stores to outgoing arguments
1527 of sibling calls. */
1528 set_mem_alias_set (args[i].stack, 0);
1529 set_mem_alias_set (args[i].stack_slot, 0);
1530 }
1531 }
1532 }
1533
1534 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1535 in a call instruction.
1536
1537 FNDECL is the tree node for the target function. For an indirect call
1538 FNDECL will be NULL_TREE.
1539
1540 ADDR is the operand 0 of CALL_EXPR for this call. */
1541
1542 static rtx
1543 rtx_for_function_call (tree fndecl, tree addr)
1544 {
1545 rtx funexp;
1546
1547 /* Get the function to call, in the form of RTL. */
1548 if (fndecl)
1549 {
1550 /* If this is the first use of the function, see if we need to
1551 make an external definition for it. */
1552 if (!TREE_USED (fndecl) && fndecl != current_function_decl)
1553 {
1554 assemble_external (fndecl);
1555 TREE_USED (fndecl) = 1;
1556 }
1557
1558 /* Get a SYMBOL_REF rtx for the function address. */
1559 funexp = XEXP (DECL_RTL (fndecl), 0);
1560 }
1561 else
1562 /* Generate an rtx (probably a pseudo-register) for the address. */
1563 {
1564 push_temp_slots ();
1565 funexp = expand_normal (addr);
1566 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1567 }
1568 return funexp;
1569 }
1570
1571 /* Return true if and only if SIZE storage units (usually bytes)
1572 starting from address ADDR overlap with already clobbered argument
1573 area. This function is used to determine if we should give up a
1574 sibcall. */
1575
1576 static bool
1577 mem_overlaps_already_clobbered_arg_p (rtx addr, unsigned HOST_WIDE_INT size)
1578 {
1579 HOST_WIDE_INT i;
1580
1581 if (addr == crtl->args.internal_arg_pointer)
1582 i = 0;
1583 else if (GET_CODE (addr) == PLUS
1584 && XEXP (addr, 0) == crtl->args.internal_arg_pointer
1585 && CONST_INT_P (XEXP (addr, 1)))
1586 i = INTVAL (XEXP (addr, 1));
1587 /* Return true for arg pointer based indexed addressing. */
1588 else if (GET_CODE (addr) == PLUS
1589 && (XEXP (addr, 0) == crtl->args.internal_arg_pointer
1590 || XEXP (addr, 1) == crtl->args.internal_arg_pointer))
1591 return true;
1592 else
1593 return false;
1594
1595 #ifdef ARGS_GROW_DOWNWARD
1596 i = -i - size;
1597 #endif
1598 if (size > 0)
1599 {
1600 unsigned HOST_WIDE_INT k;
1601
1602 for (k = 0; k < size; k++)
1603 if (i + k < stored_args_map->n_bits
1604 && TEST_BIT (stored_args_map, i + k))
1605 return true;
1606 }
1607
1608 return false;
1609 }
1610
1611 /* Do the register loads required for any wholly-register parms or any
1612 parms which are passed both on the stack and in a register. Their
1613 expressions were already evaluated.
1614
1615 Mark all register-parms as living through the call, putting these USE
1616 insns in the CALL_INSN_FUNCTION_USAGE field.
1617
1618 When IS_SIBCALL, perform the check_sibcall_argument_overlap
1619 checking, setting *SIBCALL_FAILURE if appropriate. */
1620
1621 static void
1622 load_register_parameters (struct arg_data *args, int num_actuals,
1623 rtx *call_fusage, int flags, int is_sibcall,
1624 int *sibcall_failure)
1625 {
1626 int i, j;
1627
1628 for (i = 0; i < num_actuals; i++)
1629 {
1630 rtx reg = ((flags & ECF_SIBCALL)
1631 ? args[i].tail_call_reg : args[i].reg);
1632 if (reg)
1633 {
1634 int partial = args[i].partial;
1635 int nregs;
1636 int size = 0;
1637 rtx before_arg = get_last_insn ();
1638 /* Set non-negative if we must move a word at a time, even if
1639 just one word (e.g, partial == 4 && mode == DFmode). Set
1640 to -1 if we just use a normal move insn. This value can be
1641 zero if the argument is a zero size structure. */
1642 nregs = -1;
1643 if (GET_CODE (reg) == PARALLEL)
1644 ;
1645 else if (partial)
1646 {
1647 gcc_assert (partial % UNITS_PER_WORD == 0);
1648 nregs = partial / UNITS_PER_WORD;
1649 }
1650 else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
1651 {
1652 size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1653 nregs = (size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1654 }
1655 else
1656 size = GET_MODE_SIZE (args[i].mode);
1657
1658 /* Handle calls that pass values in multiple non-contiguous
1659 locations. The Irix 6 ABI has examples of this. */
1660
1661 if (GET_CODE (reg) == PARALLEL)
1662 emit_group_move (reg, args[i].parallel_value);
1663
1664 /* If simple case, just do move. If normal partial, store_one_arg
1665 has already loaded the register for us. In all other cases,
1666 load the register(s) from memory. */
1667
1668 else if (nregs == -1)
1669 {
1670 emit_move_insn (reg, args[i].value);
1671 #ifdef BLOCK_REG_PADDING
1672 /* Handle case where we have a value that needs shifting
1673 up to the msb. eg. a QImode value and we're padding
1674 upward on a BYTES_BIG_ENDIAN machine. */
1675 if (size < UNITS_PER_WORD
1676 && (args[i].locate.where_pad
1677 == (BYTES_BIG_ENDIAN ? upward : downward)))
1678 {
1679 rtx x;
1680 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
1681
1682 /* Assigning REG here rather than a temp makes CALL_FUSAGE
1683 report the whole reg as used. Strictly speaking, the
1684 call only uses SIZE bytes at the msb end, but it doesn't
1685 seem worth generating rtl to say that. */
1686 reg = gen_rtx_REG (word_mode, REGNO (reg));
1687 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
1688 if (x != reg)
1689 emit_move_insn (reg, x);
1690 }
1691 #endif
1692 }
1693
1694 /* If we have pre-computed the values to put in the registers in
1695 the case of non-aligned structures, copy them in now. */
1696
1697 else if (args[i].n_aligned_regs != 0)
1698 for (j = 0; j < args[i].n_aligned_regs; j++)
1699 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1700 args[i].aligned_regs[j]);
1701
1702 else if (partial == 0 || args[i].pass_on_stack)
1703 {
1704 rtx mem = validize_mem (args[i].value);
1705
1706 /* Check for overlap with already clobbered argument area,
1707 providing that this has non-zero size. */
1708 if (is_sibcall
1709 && (size == 0
1710 || mem_overlaps_already_clobbered_arg_p
1711 (XEXP (args[i].value, 0), size)))
1712 *sibcall_failure = 1;
1713
1714 /* Handle a BLKmode that needs shifting. */
1715 if (nregs == 1 && size < UNITS_PER_WORD
1716 #ifdef BLOCK_REG_PADDING
1717 && args[i].locate.where_pad == downward
1718 #else
1719 && BYTES_BIG_ENDIAN
1720 #endif
1721 )
1722 {
1723 rtx tem = operand_subword_force (mem, 0, args[i].mode);
1724 rtx ri = gen_rtx_REG (word_mode, REGNO (reg));
1725 rtx x = gen_reg_rtx (word_mode);
1726 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
1727 enum tree_code dir = BYTES_BIG_ENDIAN ? RSHIFT_EXPR
1728 : LSHIFT_EXPR;
1729
1730 emit_move_insn (x, tem);
1731 x = expand_shift (dir, word_mode, x, shift, ri, 1);
1732 if (x != ri)
1733 emit_move_insn (ri, x);
1734 }
1735 else
1736 move_block_to_reg (REGNO (reg), mem, nregs, args[i].mode);
1737 }
1738
1739 /* When a parameter is a block, and perhaps in other cases, it is
1740 possible that it did a load from an argument slot that was
1741 already clobbered. */
1742 if (is_sibcall
1743 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
1744 *sibcall_failure = 1;
1745
1746 /* Handle calls that pass values in multiple non-contiguous
1747 locations. The Irix 6 ABI has examples of this. */
1748 if (GET_CODE (reg) == PARALLEL)
1749 use_group_regs (call_fusage, reg);
1750 else if (nregs == -1)
1751 use_reg (call_fusage, reg);
1752 else if (nregs > 0)
1753 use_regs (call_fusage, REGNO (reg), nregs);
1754 }
1755 }
1756 }
1757
1758 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1759 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1760 bytes, then we would need to push some additional bytes to pad the
1761 arguments. So, we compute an adjust to the stack pointer for an
1762 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1763 bytes. Then, when the arguments are pushed the stack will be perfectly
1764 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1765 be popped after the call. Returns the adjustment. */
1766
1767 static int
1768 combine_pending_stack_adjustment_and_call (int unadjusted_args_size,
1769 struct args_size *args_size,
1770 unsigned int preferred_unit_stack_boundary)
1771 {
1772 /* The number of bytes to pop so that the stack will be
1773 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1774 HOST_WIDE_INT adjustment;
1775 /* The alignment of the stack after the arguments are pushed, if we
1776 just pushed the arguments without adjust the stack here. */
1777 unsigned HOST_WIDE_INT unadjusted_alignment;
1778
1779 unadjusted_alignment
1780 = ((stack_pointer_delta + unadjusted_args_size)
1781 % preferred_unit_stack_boundary);
1782
1783 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1784 as possible -- leaving just enough left to cancel out the
1785 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1786 PENDING_STACK_ADJUST is non-negative, and congruent to
1787 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
1788
1789 /* Begin by trying to pop all the bytes. */
1790 unadjusted_alignment
1791 = (unadjusted_alignment
1792 - (pending_stack_adjust % preferred_unit_stack_boundary));
1793 adjustment = pending_stack_adjust;
1794 /* Push enough additional bytes that the stack will be aligned
1795 after the arguments are pushed. */
1796 if (preferred_unit_stack_boundary > 1)
1797 {
1798 if (unadjusted_alignment > 0)
1799 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
1800 else
1801 adjustment += unadjusted_alignment;
1802 }
1803
1804 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
1805 bytes after the call. The right number is the entire
1806 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
1807 by the arguments in the first place. */
1808 args_size->constant
1809 = pending_stack_adjust - adjustment + unadjusted_args_size;
1810
1811 return adjustment;
1812 }
1813
1814 /* Scan X expression if it does not dereference any argument slots
1815 we already clobbered by tail call arguments (as noted in stored_args_map
1816 bitmap).
1817 Return nonzero if X expression dereferences such argument slots,
1818 zero otherwise. */
1819
1820 static int
1821 check_sibcall_argument_overlap_1 (rtx x)
1822 {
1823 RTX_CODE code;
1824 int i, j;
1825 const char *fmt;
1826
1827 if (x == NULL_RTX)
1828 return 0;
1829
1830 code = GET_CODE (x);
1831
1832 if (code == MEM)
1833 return mem_overlaps_already_clobbered_arg_p (XEXP (x, 0),
1834 GET_MODE_SIZE (GET_MODE (x)));
1835
1836 /* Scan all subexpressions. */
1837 fmt = GET_RTX_FORMAT (code);
1838 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
1839 {
1840 if (*fmt == 'e')
1841 {
1842 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
1843 return 1;
1844 }
1845 else if (*fmt == 'E')
1846 {
1847 for (j = 0; j < XVECLEN (x, i); j++)
1848 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
1849 return 1;
1850 }
1851 }
1852 return 0;
1853 }
1854
1855 /* Scan sequence after INSN if it does not dereference any argument slots
1856 we already clobbered by tail call arguments (as noted in stored_args_map
1857 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
1858 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
1859 should be 0). Return nonzero if sequence after INSN dereferences such argument
1860 slots, zero otherwise. */
1861
1862 static int
1863 check_sibcall_argument_overlap (rtx insn, struct arg_data *arg, int mark_stored_args_map)
1864 {
1865 int low, high;
1866
1867 if (insn == NULL_RTX)
1868 insn = get_insns ();
1869 else
1870 insn = NEXT_INSN (insn);
1871
1872 for (; insn; insn = NEXT_INSN (insn))
1873 if (INSN_P (insn)
1874 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
1875 break;
1876
1877 if (mark_stored_args_map)
1878 {
1879 #ifdef ARGS_GROW_DOWNWARD
1880 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
1881 #else
1882 low = arg->locate.slot_offset.constant;
1883 #endif
1884
1885 for (high = low + arg->locate.size.constant; low < high; low++)
1886 SET_BIT (stored_args_map, low);
1887 }
1888 return insn != NULL_RTX;
1889 }
1890
1891 /* Given that a function returns a value of mode MODE at the most
1892 significant end of hard register VALUE, shift VALUE left or right
1893 as specified by LEFT_P. Return true if some action was needed. */
1894
1895 bool
1896 shift_return_value (enum machine_mode mode, bool left_p, rtx value)
1897 {
1898 HOST_WIDE_INT shift;
1899
1900 gcc_assert (REG_P (value) && HARD_REGISTER_P (value));
1901 shift = GET_MODE_BITSIZE (GET_MODE (value)) - GET_MODE_BITSIZE (mode);
1902 if (shift == 0)
1903 return false;
1904
1905 /* Use ashr rather than lshr for right shifts. This is for the benefit
1906 of the MIPS port, which requires SImode values to be sign-extended
1907 when stored in 64-bit registers. */
1908 if (!force_expand_binop (GET_MODE (value), left_p ? ashl_optab : ashr_optab,
1909 value, GEN_INT (shift), value, 1, OPTAB_WIDEN))
1910 gcc_unreachable ();
1911 return true;
1912 }
1913
1914 /* If X is a likely-spilled register value, copy it to a pseudo
1915 register and return that register. Return X otherwise. */
1916
1917 static rtx
1918 avoid_likely_spilled_reg (rtx x)
1919 {
1920 rtx new_rtx;
1921
1922 if (REG_P (x)
1923 && HARD_REGISTER_P (x)
1924 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x))))
1925 {
1926 /* Make sure that we generate a REG rather than a CONCAT.
1927 Moves into CONCATs can need nontrivial instructions,
1928 and the whole point of this function is to avoid
1929 using the hard register directly in such a situation. */
1930 generating_concat_p = 0;
1931 new_rtx = gen_reg_rtx (GET_MODE (x));
1932 generating_concat_p = 1;
1933 emit_move_insn (new_rtx, x);
1934 return new_rtx;
1935 }
1936 return x;
1937 }
1938
1939 /* Generate all the code for a CALL_EXPR exp
1940 and return an rtx for its value.
1941 Store the value in TARGET (specified as an rtx) if convenient.
1942 If the value is stored in TARGET then TARGET is returned.
1943 If IGNORE is nonzero, then we ignore the value of the function call. */
1944
1945 rtx
1946 expand_call (tree exp, rtx target, int ignore)
1947 {
1948 /* Nonzero if we are currently expanding a call. */
1949 static int currently_expanding_call = 0;
1950
1951 /* RTX for the function to be called. */
1952 rtx funexp;
1953 /* Sequence of insns to perform a normal "call". */
1954 rtx normal_call_insns = NULL_RTX;
1955 /* Sequence of insns to perform a tail "call". */
1956 rtx tail_call_insns = NULL_RTX;
1957 /* Data type of the function. */
1958 tree funtype;
1959 tree type_arg_types;
1960 tree rettype;
1961 /* Declaration of the function being called,
1962 or 0 if the function is computed (not known by name). */
1963 tree fndecl = 0;
1964 /* The type of the function being called. */
1965 tree fntype;
1966 bool try_tail_call = CALL_EXPR_TAILCALL (exp);
1967 int pass;
1968
1969 /* Register in which non-BLKmode value will be returned,
1970 or 0 if no value or if value is BLKmode. */
1971 rtx valreg;
1972 /* Address where we should return a BLKmode value;
1973 0 if value not BLKmode. */
1974 rtx structure_value_addr = 0;
1975 /* Nonzero if that address is being passed by treating it as
1976 an extra, implicit first parameter. Otherwise,
1977 it is passed by being copied directly into struct_value_rtx. */
1978 int structure_value_addr_parm = 0;
1979 /* Holds the value of implicit argument for the struct value. */
1980 tree structure_value_addr_value = NULL_TREE;
1981 /* Size of aggregate value wanted, or zero if none wanted
1982 or if we are using the non-reentrant PCC calling convention
1983 or expecting the value in registers. */
1984 HOST_WIDE_INT struct_value_size = 0;
1985 /* Nonzero if called function returns an aggregate in memory PCC style,
1986 by returning the address of where to find it. */
1987 int pcc_struct_value = 0;
1988 rtx struct_value = 0;
1989
1990 /* Number of actual parameters in this call, including struct value addr. */
1991 int num_actuals;
1992 /* Number of named args. Args after this are anonymous ones
1993 and they must all go on the stack. */
1994 int n_named_args;
1995 /* Number of complex actual arguments that need to be split. */
1996 int num_complex_actuals = 0;
1997
1998 /* Vector of information about each argument.
1999 Arguments are numbered in the order they will be pushed,
2000 not the order they are written. */
2001 struct arg_data *args;
2002
2003 /* Total size in bytes of all the stack-parms scanned so far. */
2004 struct args_size args_size;
2005 struct args_size adjusted_args_size;
2006 /* Size of arguments before any adjustments (such as rounding). */
2007 int unadjusted_args_size;
2008 /* Data on reg parms scanned so far. */
2009 CUMULATIVE_ARGS args_so_far_v;
2010 cumulative_args_t args_so_far;
2011 /* Nonzero if a reg parm has been scanned. */
2012 int reg_parm_seen;
2013 /* Nonzero if this is an indirect function call. */
2014
2015 /* Nonzero if we must avoid push-insns in the args for this call.
2016 If stack space is allocated for register parameters, but not by the
2017 caller, then it is preallocated in the fixed part of the stack frame.
2018 So the entire argument block must then be preallocated (i.e., we
2019 ignore PUSH_ROUNDING in that case). */
2020
2021 int must_preallocate = !PUSH_ARGS;
2022
2023 /* Size of the stack reserved for parameter registers. */
2024 int reg_parm_stack_space = 0;
2025
2026 /* Address of space preallocated for stack parms
2027 (on machines that lack push insns), or 0 if space not preallocated. */
2028 rtx argblock = 0;
2029
2030 /* Mask of ECF_ flags. */
2031 int flags = 0;
2032 #ifdef REG_PARM_STACK_SPACE
2033 /* Define the boundary of the register parm stack space that needs to be
2034 saved, if any. */
2035 int low_to_save, high_to_save;
2036 rtx save_area = 0; /* Place that it is saved */
2037 #endif
2038
2039 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2040 char *initial_stack_usage_map = stack_usage_map;
2041 char *stack_usage_map_buf = NULL;
2042
2043 int old_stack_allocated;
2044
2045 /* State variables to track stack modifications. */
2046 rtx old_stack_level = 0;
2047 int old_stack_arg_under_construction = 0;
2048 int old_pending_adj = 0;
2049 int old_inhibit_defer_pop = inhibit_defer_pop;
2050
2051 /* Some stack pointer alterations we make are performed via
2052 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
2053 which we then also need to save/restore along the way. */
2054 int old_stack_pointer_delta = 0;
2055
2056 rtx call_fusage;
2057 tree addr = CALL_EXPR_FN (exp);
2058 int i;
2059 /* The alignment of the stack, in bits. */
2060 unsigned HOST_WIDE_INT preferred_stack_boundary;
2061 /* The alignment of the stack, in bytes. */
2062 unsigned HOST_WIDE_INT preferred_unit_stack_boundary;
2063 /* The static chain value to use for this call. */
2064 rtx static_chain_value;
2065 /* See if this is "nothrow" function call. */
2066 if (TREE_NOTHROW (exp))
2067 flags |= ECF_NOTHROW;
2068
2069 /* See if we can find a DECL-node for the actual function, and get the
2070 function attributes (flags) from the function decl or type node. */
2071 fndecl = get_callee_fndecl (exp);
2072 if (fndecl)
2073 {
2074 fntype = TREE_TYPE (fndecl);
2075 flags |= flags_from_decl_or_type (fndecl);
2076 }
2077 else
2078 {
2079 fntype = TREE_TYPE (TREE_TYPE (addr));
2080 flags |= flags_from_decl_or_type (fntype);
2081 }
2082 rettype = TREE_TYPE (exp);
2083
2084 struct_value = targetm.calls.struct_value_rtx (fntype, 0);
2085
2086 /* Warn if this value is an aggregate type,
2087 regardless of which calling convention we are using for it. */
2088 if (AGGREGATE_TYPE_P (rettype))
2089 warning (OPT_Waggregate_return, "function call has aggregate value");
2090
2091 /* If the result of a non looping pure or const function call is
2092 ignored (or void), and none of its arguments are volatile, we can
2093 avoid expanding the call and just evaluate the arguments for
2094 side-effects. */
2095 if ((flags & (ECF_CONST | ECF_PURE))
2096 && (!(flags & ECF_LOOPING_CONST_OR_PURE))
2097 && (ignore || target == const0_rtx
2098 || TYPE_MODE (rettype) == VOIDmode))
2099 {
2100 bool volatilep = false;
2101 tree arg;
2102 call_expr_arg_iterator iter;
2103
2104 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2105 if (TREE_THIS_VOLATILE (arg))
2106 {
2107 volatilep = true;
2108 break;
2109 }
2110
2111 if (! volatilep)
2112 {
2113 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2114 expand_expr (arg, const0_rtx, VOIDmode, EXPAND_NORMAL);
2115 return const0_rtx;
2116 }
2117 }
2118
2119 #ifdef REG_PARM_STACK_SPACE
2120 reg_parm_stack_space = REG_PARM_STACK_SPACE (!fndecl ? fntype : fndecl);
2121 #endif
2122
2123 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
2124 && reg_parm_stack_space > 0 && PUSH_ARGS)
2125 must_preallocate = 1;
2126
2127 /* Set up a place to return a structure. */
2128
2129 /* Cater to broken compilers. */
2130 if (aggregate_value_p (exp, fntype))
2131 {
2132 /* This call returns a big structure. */
2133 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
2134
2135 #ifdef PCC_STATIC_STRUCT_RETURN
2136 {
2137 pcc_struct_value = 1;
2138 }
2139 #else /* not PCC_STATIC_STRUCT_RETURN */
2140 {
2141 struct_value_size = int_size_in_bytes (rettype);
2142
2143 if (target && MEM_P (target) && CALL_EXPR_RETURN_SLOT_OPT (exp))
2144 structure_value_addr = XEXP (target, 0);
2145 else
2146 {
2147 /* For variable-sized objects, we must be called with a target
2148 specified. If we were to allocate space on the stack here,
2149 we would have no way of knowing when to free it. */
2150 rtx d = assign_temp (rettype, 0, 1, 1);
2151
2152 mark_temp_addr_taken (d);
2153 structure_value_addr = XEXP (d, 0);
2154 target = 0;
2155 }
2156 }
2157 #endif /* not PCC_STATIC_STRUCT_RETURN */
2158 }
2159
2160 /* Figure out the amount to which the stack should be aligned. */
2161 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2162 if (fndecl)
2163 {
2164 struct cgraph_rtl_info *i = cgraph_rtl_info (fndecl);
2165 /* Without automatic stack alignment, we can't increase preferred
2166 stack boundary. With automatic stack alignment, it is
2167 unnecessary since unless we can guarantee that all callers will
2168 align the outgoing stack properly, callee has to align its
2169 stack anyway. */
2170 if (i
2171 && i->preferred_incoming_stack_boundary
2172 && i->preferred_incoming_stack_boundary < preferred_stack_boundary)
2173 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
2174 }
2175
2176 /* Operand 0 is a pointer-to-function; get the type of the function. */
2177 funtype = TREE_TYPE (addr);
2178 gcc_assert (POINTER_TYPE_P (funtype));
2179 funtype = TREE_TYPE (funtype);
2180
2181 /* Count whether there are actual complex arguments that need to be split
2182 into their real and imaginary parts. Munge the type_arg_types
2183 appropriately here as well. */
2184 if (targetm.calls.split_complex_arg)
2185 {
2186 call_expr_arg_iterator iter;
2187 tree arg;
2188 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2189 {
2190 tree type = TREE_TYPE (arg);
2191 if (type && TREE_CODE (type) == COMPLEX_TYPE
2192 && targetm.calls.split_complex_arg (type))
2193 num_complex_actuals++;
2194 }
2195 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
2196 }
2197 else
2198 type_arg_types = TYPE_ARG_TYPES (funtype);
2199
2200 if (flags & ECF_MAY_BE_ALLOCA)
2201 cfun->calls_alloca = 1;
2202
2203 /* If struct_value_rtx is 0, it means pass the address
2204 as if it were an extra parameter. Put the argument expression
2205 in structure_value_addr_value. */
2206 if (structure_value_addr && struct_value == 0)
2207 {
2208 /* If structure_value_addr is a REG other than
2209 virtual_outgoing_args_rtx, we can use always use it. If it
2210 is not a REG, we must always copy it into a register.
2211 If it is virtual_outgoing_args_rtx, we must copy it to another
2212 register in some cases. */
2213 rtx temp = (!REG_P (structure_value_addr)
2214 || (ACCUMULATE_OUTGOING_ARGS
2215 && stack_arg_under_construction
2216 && structure_value_addr == virtual_outgoing_args_rtx)
2217 ? copy_addr_to_reg (convert_memory_address
2218 (Pmode, structure_value_addr))
2219 : structure_value_addr);
2220
2221 structure_value_addr_value =
2222 make_tree (build_pointer_type (TREE_TYPE (funtype)), temp);
2223 structure_value_addr_parm = 1;
2224 }
2225
2226 /* Count the arguments and set NUM_ACTUALS. */
2227 num_actuals =
2228 call_expr_nargs (exp) + num_complex_actuals + structure_value_addr_parm;
2229
2230 /* Compute number of named args.
2231 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
2232
2233 if (type_arg_types != 0)
2234 n_named_args
2235 = (list_length (type_arg_types)
2236 /* Count the struct value address, if it is passed as a parm. */
2237 + structure_value_addr_parm);
2238 else
2239 /* If we know nothing, treat all args as named. */
2240 n_named_args = num_actuals;
2241
2242 /* Start updating where the next arg would go.
2243
2244 On some machines (such as the PA) indirect calls have a different
2245 calling convention than normal calls. The fourth argument in
2246 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2247 or not. */
2248 INIT_CUMULATIVE_ARGS (args_so_far_v, funtype, NULL_RTX, fndecl, n_named_args);
2249 args_so_far = pack_cumulative_args (&args_so_far_v);
2250
2251 /* Now possibly adjust the number of named args.
2252 Normally, don't include the last named arg if anonymous args follow.
2253 We do include the last named arg if
2254 targetm.calls.strict_argument_naming() returns nonzero.
2255 (If no anonymous args follow, the result of list_length is actually
2256 one too large. This is harmless.)
2257
2258 If targetm.calls.pretend_outgoing_varargs_named() returns
2259 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2260 this machine will be able to place unnamed args that were passed
2261 in registers into the stack. So treat all args as named. This
2262 allows the insns emitting for a specific argument list to be
2263 independent of the function declaration.
2264
2265 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2266 we do not have any reliable way to pass unnamed args in
2267 registers, so we must force them into memory. */
2268
2269 if (type_arg_types != 0
2270 && targetm.calls.strict_argument_naming (args_so_far))
2271 ;
2272 else if (type_arg_types != 0
2273 && ! targetm.calls.pretend_outgoing_varargs_named (args_so_far))
2274 /* Don't include the last named arg. */
2275 --n_named_args;
2276 else
2277 /* Treat all args as named. */
2278 n_named_args = num_actuals;
2279
2280 /* Make a vector to hold all the information about each arg. */
2281 args = XALLOCAVEC (struct arg_data, num_actuals);
2282 memset (args, 0, num_actuals * sizeof (struct arg_data));
2283
2284 /* Build up entries in the ARGS array, compute the size of the
2285 arguments into ARGS_SIZE, etc. */
2286 initialize_argument_information (num_actuals, args, &args_size,
2287 n_named_args, exp,
2288 structure_value_addr_value, fndecl, fntype,
2289 args_so_far, reg_parm_stack_space,
2290 &old_stack_level, &old_pending_adj,
2291 &must_preallocate, &flags,
2292 &try_tail_call, CALL_FROM_THUNK_P (exp));
2293
2294 if (args_size.var)
2295 must_preallocate = 1;
2296
2297 /* Now make final decision about preallocating stack space. */
2298 must_preallocate = finalize_must_preallocate (must_preallocate,
2299 num_actuals, args,
2300 &args_size);
2301
2302 /* If the structure value address will reference the stack pointer, we
2303 must stabilize it. We don't need to do this if we know that we are
2304 not going to adjust the stack pointer in processing this call. */
2305
2306 if (structure_value_addr
2307 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2308 || reg_mentioned_p (virtual_outgoing_args_rtx,
2309 structure_value_addr))
2310 && (args_size.var
2311 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2312 structure_value_addr = copy_to_reg (structure_value_addr);
2313
2314 /* Tail calls can make things harder to debug, and we've traditionally
2315 pushed these optimizations into -O2. Don't try if we're already
2316 expanding a call, as that means we're an argument. Don't try if
2317 there's cleanups, as we know there's code to follow the call. */
2318
2319 if (currently_expanding_call++ != 0
2320 || !flag_optimize_sibling_calls
2321 || args_size.var
2322 || dbg_cnt (tail_call) == false)
2323 try_tail_call = 0;
2324
2325 /* Rest of purposes for tail call optimizations to fail. */
2326 if (
2327 #ifdef HAVE_sibcall_epilogue
2328 !HAVE_sibcall_epilogue
2329 #else
2330 1
2331 #endif
2332 || !try_tail_call
2333 /* Doing sibling call optimization needs some work, since
2334 structure_value_addr can be allocated on the stack.
2335 It does not seem worth the effort since few optimizable
2336 sibling calls will return a structure. */
2337 || structure_value_addr != NULL_RTX
2338 #ifdef REG_PARM_STACK_SPACE
2339 /* If outgoing reg parm stack space changes, we can not do sibcall. */
2340 || (OUTGOING_REG_PARM_STACK_SPACE (funtype)
2341 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl)))
2342 || (reg_parm_stack_space != REG_PARM_STACK_SPACE (fndecl))
2343 #endif
2344 /* Check whether the target is able to optimize the call
2345 into a sibcall. */
2346 || !targetm.function_ok_for_sibcall (fndecl, exp)
2347 /* Functions that do not return exactly once may not be sibcall
2348 optimized. */
2349 || (flags & (ECF_RETURNS_TWICE | ECF_NORETURN))
2350 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr)))
2351 /* If the called function is nested in the current one, it might access
2352 some of the caller's arguments, but could clobber them beforehand if
2353 the argument areas are shared. */
2354 || (fndecl && decl_function_context (fndecl) == current_function_decl)
2355 /* If this function requires more stack slots than the current
2356 function, we cannot change it into a sibling call.
2357 crtl->args.pretend_args_size is not part of the
2358 stack allocated by our caller. */
2359 || args_size.constant > (crtl->args.size
2360 - crtl->args.pretend_args_size)
2361 /* If the callee pops its own arguments, then it must pop exactly
2362 the same number of arguments as the current function. */
2363 || (targetm.calls.return_pops_args (fndecl, funtype, args_size.constant)
2364 != targetm.calls.return_pops_args (current_function_decl,
2365 TREE_TYPE (current_function_decl),
2366 crtl->args.size))
2367 || !lang_hooks.decls.ok_for_sibcall (fndecl))
2368 try_tail_call = 0;
2369
2370 /* Check if caller and callee disagree in promotion of function
2371 return value. */
2372 if (try_tail_call)
2373 {
2374 enum machine_mode caller_mode, caller_promoted_mode;
2375 enum machine_mode callee_mode, callee_promoted_mode;
2376 int caller_unsignedp, callee_unsignedp;
2377 tree caller_res = DECL_RESULT (current_function_decl);
2378
2379 caller_unsignedp = TYPE_UNSIGNED (TREE_TYPE (caller_res));
2380 caller_mode = DECL_MODE (caller_res);
2381 callee_unsignedp = TYPE_UNSIGNED (TREE_TYPE (funtype));
2382 callee_mode = TYPE_MODE (TREE_TYPE (funtype));
2383 caller_promoted_mode
2384 = promote_function_mode (TREE_TYPE (caller_res), caller_mode,
2385 &caller_unsignedp,
2386 TREE_TYPE (current_function_decl), 1);
2387 callee_promoted_mode
2388 = promote_function_mode (TREE_TYPE (funtype), callee_mode,
2389 &callee_unsignedp,
2390 funtype, 1);
2391 if (caller_mode != VOIDmode
2392 && (caller_promoted_mode != callee_promoted_mode
2393 || ((caller_mode != caller_promoted_mode
2394 || callee_mode != callee_promoted_mode)
2395 && (caller_unsignedp != callee_unsignedp
2396 || GET_MODE_BITSIZE (caller_mode)
2397 < GET_MODE_BITSIZE (callee_mode)))))
2398 try_tail_call = 0;
2399 }
2400
2401 /* Ensure current function's preferred stack boundary is at least
2402 what we need. Stack alignment may also increase preferred stack
2403 boundary. */
2404 if (crtl->preferred_stack_boundary < preferred_stack_boundary)
2405 crtl->preferred_stack_boundary = preferred_stack_boundary;
2406 else
2407 preferred_stack_boundary = crtl->preferred_stack_boundary;
2408
2409 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2410
2411 /* We want to make two insn chains; one for a sibling call, the other
2412 for a normal call. We will select one of the two chains after
2413 initial RTL generation is complete. */
2414 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
2415 {
2416 int sibcall_failure = 0;
2417 /* We want to emit any pending stack adjustments before the tail
2418 recursion "call". That way we know any adjustment after the tail
2419 recursion call can be ignored if we indeed use the tail
2420 call expansion. */
2421 int save_pending_stack_adjust = 0;
2422 int save_stack_pointer_delta = 0;
2423 rtx insns;
2424 rtx before_call, next_arg_reg, after_args;
2425
2426 if (pass == 0)
2427 {
2428 /* State variables we need to save and restore between
2429 iterations. */
2430 save_pending_stack_adjust = pending_stack_adjust;
2431 save_stack_pointer_delta = stack_pointer_delta;
2432 }
2433 if (pass)
2434 flags &= ~ECF_SIBCALL;
2435 else
2436 flags |= ECF_SIBCALL;
2437
2438 /* Other state variables that we must reinitialize each time
2439 through the loop (that are not initialized by the loop itself). */
2440 argblock = 0;
2441 call_fusage = 0;
2442
2443 /* Start a new sequence for the normal call case.
2444
2445 From this point on, if the sibling call fails, we want to set
2446 sibcall_failure instead of continuing the loop. */
2447 start_sequence ();
2448
2449 /* Don't let pending stack adjusts add up to too much.
2450 Also, do all pending adjustments now if there is any chance
2451 this might be a call to alloca or if we are expanding a sibling
2452 call sequence.
2453 Also do the adjustments before a throwing call, otherwise
2454 exception handling can fail; PR 19225. */
2455 if (pending_stack_adjust >= 32
2456 || (pending_stack_adjust > 0
2457 && (flags & ECF_MAY_BE_ALLOCA))
2458 || (pending_stack_adjust > 0
2459 && flag_exceptions && !(flags & ECF_NOTHROW))
2460 || pass == 0)
2461 do_pending_stack_adjust ();
2462
2463 /* Precompute any arguments as needed. */
2464 if (pass)
2465 precompute_arguments (num_actuals, args);
2466
2467 /* Now we are about to start emitting insns that can be deleted
2468 if a libcall is deleted. */
2469 if (pass && (flags & ECF_MALLOC))
2470 start_sequence ();
2471
2472 if (pass == 0 && crtl->stack_protect_guard)
2473 stack_protect_epilogue ();
2474
2475 adjusted_args_size = args_size;
2476 /* Compute the actual size of the argument block required. The variable
2477 and constant sizes must be combined, the size may have to be rounded,
2478 and there may be a minimum required size. When generating a sibcall
2479 pattern, do not round up, since we'll be re-using whatever space our
2480 caller provided. */
2481 unadjusted_args_size
2482 = compute_argument_block_size (reg_parm_stack_space,
2483 &adjusted_args_size,
2484 fndecl, fntype,
2485 (pass == 0 ? 0
2486 : preferred_stack_boundary));
2487
2488 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2489
2490 /* The argument block when performing a sibling call is the
2491 incoming argument block. */
2492 if (pass == 0)
2493 {
2494 argblock = crtl->args.internal_arg_pointer;
2495 argblock
2496 #ifdef STACK_GROWS_DOWNWARD
2497 = plus_constant (argblock, crtl->args.pretend_args_size);
2498 #else
2499 = plus_constant (argblock, -crtl->args.pretend_args_size);
2500 #endif
2501 stored_args_map = sbitmap_alloc (args_size.constant);
2502 sbitmap_zero (stored_args_map);
2503 }
2504
2505 /* If we have no actual push instructions, or shouldn't use them,
2506 make space for all args right now. */
2507 else if (adjusted_args_size.var != 0)
2508 {
2509 if (old_stack_level == 0)
2510 {
2511 emit_stack_save (SAVE_BLOCK, &old_stack_level);
2512 old_stack_pointer_delta = stack_pointer_delta;
2513 old_pending_adj = pending_stack_adjust;
2514 pending_stack_adjust = 0;
2515 /* stack_arg_under_construction says whether a stack arg is
2516 being constructed at the old stack level. Pushing the stack
2517 gets a clean outgoing argument block. */
2518 old_stack_arg_under_construction = stack_arg_under_construction;
2519 stack_arg_under_construction = 0;
2520 }
2521 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2522 if (flag_stack_usage_info)
2523 current_function_has_unbounded_dynamic_stack_size = 1;
2524 }
2525 else
2526 {
2527 /* Note that we must go through the motions of allocating an argument
2528 block even if the size is zero because we may be storing args
2529 in the area reserved for register arguments, which may be part of
2530 the stack frame. */
2531
2532 int needed = adjusted_args_size.constant;
2533
2534 /* Store the maximum argument space used. It will be pushed by
2535 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2536 checking). */
2537
2538 if (needed > crtl->outgoing_args_size)
2539 crtl->outgoing_args_size = needed;
2540
2541 if (must_preallocate)
2542 {
2543 if (ACCUMULATE_OUTGOING_ARGS)
2544 {
2545 /* Since the stack pointer will never be pushed, it is
2546 possible for the evaluation of a parm to clobber
2547 something we have already written to the stack.
2548 Since most function calls on RISC machines do not use
2549 the stack, this is uncommon, but must work correctly.
2550
2551 Therefore, we save any area of the stack that was already
2552 written and that we are using. Here we set up to do this
2553 by making a new stack usage map from the old one. The
2554 actual save will be done by store_one_arg.
2555
2556 Another approach might be to try to reorder the argument
2557 evaluations to avoid this conflicting stack usage. */
2558
2559 /* Since we will be writing into the entire argument area,
2560 the map must be allocated for its entire size, not just
2561 the part that is the responsibility of the caller. */
2562 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
2563 needed += reg_parm_stack_space;
2564
2565 #ifdef ARGS_GROW_DOWNWARD
2566 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2567 needed + 1);
2568 #else
2569 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2570 needed);
2571 #endif
2572 free (stack_usage_map_buf);
2573 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
2574 stack_usage_map = stack_usage_map_buf;
2575
2576 if (initial_highest_arg_in_use)
2577 memcpy (stack_usage_map, initial_stack_usage_map,
2578 initial_highest_arg_in_use);
2579
2580 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2581 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2582 (highest_outgoing_arg_in_use
2583 - initial_highest_arg_in_use));
2584 needed = 0;
2585
2586 /* The address of the outgoing argument list must not be
2587 copied to a register here, because argblock would be left
2588 pointing to the wrong place after the call to
2589 allocate_dynamic_stack_space below. */
2590
2591 argblock = virtual_outgoing_args_rtx;
2592 }
2593 else
2594 {
2595 if (inhibit_defer_pop == 0)
2596 {
2597 /* Try to reuse some or all of the pending_stack_adjust
2598 to get this space. */
2599 needed
2600 = (combine_pending_stack_adjustment_and_call
2601 (unadjusted_args_size,
2602 &adjusted_args_size,
2603 preferred_unit_stack_boundary));
2604
2605 /* combine_pending_stack_adjustment_and_call computes
2606 an adjustment before the arguments are allocated.
2607 Account for them and see whether or not the stack
2608 needs to go up or down. */
2609 needed = unadjusted_args_size - needed;
2610
2611 if (needed < 0)
2612 {
2613 /* We're releasing stack space. */
2614 /* ??? We can avoid any adjustment at all if we're
2615 already aligned. FIXME. */
2616 pending_stack_adjust = -needed;
2617 do_pending_stack_adjust ();
2618 needed = 0;
2619 }
2620 else
2621 /* We need to allocate space. We'll do that in
2622 push_block below. */
2623 pending_stack_adjust = 0;
2624 }
2625
2626 /* Special case this because overhead of `push_block' in
2627 this case is non-trivial. */
2628 if (needed == 0)
2629 argblock = virtual_outgoing_args_rtx;
2630 else
2631 {
2632 argblock = push_block (GEN_INT (needed), 0, 0);
2633 #ifdef ARGS_GROW_DOWNWARD
2634 argblock = plus_constant (argblock, needed);
2635 #endif
2636 }
2637
2638 /* We only really need to call `copy_to_reg' in the case
2639 where push insns are going to be used to pass ARGBLOCK
2640 to a function call in ARGS. In that case, the stack
2641 pointer changes value from the allocation point to the
2642 call point, and hence the value of
2643 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2644 as well always do it. */
2645 argblock = copy_to_reg (argblock);
2646 }
2647 }
2648 }
2649
2650 if (ACCUMULATE_OUTGOING_ARGS)
2651 {
2652 /* The save/restore code in store_one_arg handles all
2653 cases except one: a constructor call (including a C
2654 function returning a BLKmode struct) to initialize
2655 an argument. */
2656 if (stack_arg_under_construction)
2657 {
2658 rtx push_size
2659 = GEN_INT (adjusted_args_size.constant
2660 + (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype
2661 : TREE_TYPE (fndecl))) ? 0
2662 : reg_parm_stack_space));
2663 if (old_stack_level == 0)
2664 {
2665 emit_stack_save (SAVE_BLOCK, &old_stack_level);
2666 old_stack_pointer_delta = stack_pointer_delta;
2667 old_pending_adj = pending_stack_adjust;
2668 pending_stack_adjust = 0;
2669 /* stack_arg_under_construction says whether a stack
2670 arg is being constructed at the old stack level.
2671 Pushing the stack gets a clean outgoing argument
2672 block. */
2673 old_stack_arg_under_construction
2674 = stack_arg_under_construction;
2675 stack_arg_under_construction = 0;
2676 /* Make a new map for the new argument list. */
2677 free (stack_usage_map_buf);
2678 stack_usage_map_buf = XCNEWVEC (char, highest_outgoing_arg_in_use);
2679 stack_usage_map = stack_usage_map_buf;
2680 highest_outgoing_arg_in_use = 0;
2681 }
2682 /* We can pass TRUE as the 4th argument because we just
2683 saved the stack pointer and will restore it right after
2684 the call. */
2685 allocate_dynamic_stack_space (push_size, 0,
2686 BIGGEST_ALIGNMENT, true);
2687 }
2688
2689 /* If argument evaluation might modify the stack pointer,
2690 copy the address of the argument list to a register. */
2691 for (i = 0; i < num_actuals; i++)
2692 if (args[i].pass_on_stack)
2693 {
2694 argblock = copy_addr_to_reg (argblock);
2695 break;
2696 }
2697 }
2698
2699 compute_argument_addresses (args, argblock, num_actuals);
2700
2701 /* If we push args individually in reverse order, perform stack alignment
2702 before the first push (the last arg). */
2703 if (PUSH_ARGS_REVERSED && argblock == 0
2704 && adjusted_args_size.constant != unadjusted_args_size)
2705 {
2706 /* When the stack adjustment is pending, we get better code
2707 by combining the adjustments. */
2708 if (pending_stack_adjust
2709 && ! inhibit_defer_pop)
2710 {
2711 pending_stack_adjust
2712 = (combine_pending_stack_adjustment_and_call
2713 (unadjusted_args_size,
2714 &adjusted_args_size,
2715 preferred_unit_stack_boundary));
2716 do_pending_stack_adjust ();
2717 }
2718 else if (argblock == 0)
2719 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2720 - unadjusted_args_size));
2721 }
2722 /* Now that the stack is properly aligned, pops can't safely
2723 be deferred during the evaluation of the arguments. */
2724 NO_DEFER_POP;
2725
2726 /* Record the maximum pushed stack space size. We need to delay
2727 doing it this far to take into account the optimization done
2728 by combine_pending_stack_adjustment_and_call. */
2729 if (flag_stack_usage_info
2730 && !ACCUMULATE_OUTGOING_ARGS
2731 && pass
2732 && adjusted_args_size.var == 0)
2733 {
2734 int pushed = adjusted_args_size.constant + pending_stack_adjust;
2735 if (pushed > current_function_pushed_stack_size)
2736 current_function_pushed_stack_size = pushed;
2737 }
2738
2739 funexp = rtx_for_function_call (fndecl, addr);
2740
2741 /* Figure out the register where the value, if any, will come back. */
2742 valreg = 0;
2743 if (TYPE_MODE (rettype) != VOIDmode
2744 && ! structure_value_addr)
2745 {
2746 if (pcc_struct_value)
2747 valreg = hard_function_value (build_pointer_type (rettype),
2748 fndecl, NULL, (pass == 0));
2749 else
2750 valreg = hard_function_value (rettype, fndecl, fntype,
2751 (pass == 0));
2752
2753 /* If VALREG is a PARALLEL whose first member has a zero
2754 offset, use that. This is for targets such as m68k that
2755 return the same value in multiple places. */
2756 if (GET_CODE (valreg) == PARALLEL)
2757 {
2758 rtx elem = XVECEXP (valreg, 0, 0);
2759 rtx where = XEXP (elem, 0);
2760 rtx offset = XEXP (elem, 1);
2761 if (offset == const0_rtx
2762 && GET_MODE (where) == GET_MODE (valreg))
2763 valreg = where;
2764 }
2765 }
2766
2767 /* Precompute all register parameters. It isn't safe to compute anything
2768 once we have started filling any specific hard regs. */
2769 precompute_register_parameters (num_actuals, args, &reg_parm_seen);
2770
2771 if (CALL_EXPR_STATIC_CHAIN (exp))
2772 static_chain_value = expand_normal (CALL_EXPR_STATIC_CHAIN (exp));
2773 else
2774 static_chain_value = 0;
2775
2776 #ifdef REG_PARM_STACK_SPACE
2777 /* Save the fixed argument area if it's part of the caller's frame and
2778 is clobbered by argument setup for this call. */
2779 if (ACCUMULATE_OUTGOING_ARGS && pass)
2780 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2781 &low_to_save, &high_to_save);
2782 #endif
2783
2784 /* Now store (and compute if necessary) all non-register parms.
2785 These come before register parms, since they can require block-moves,
2786 which could clobber the registers used for register parms.
2787 Parms which have partial registers are not stored here,
2788 but we do preallocate space here if they want that. */
2789
2790 for (i = 0; i < num_actuals; i++)
2791 {
2792 if (args[i].reg == 0 || args[i].pass_on_stack)
2793 {
2794 rtx before_arg = get_last_insn ();
2795
2796 if (store_one_arg (&args[i], argblock, flags,
2797 adjusted_args_size.var != 0,
2798 reg_parm_stack_space)
2799 || (pass == 0
2800 && check_sibcall_argument_overlap (before_arg,
2801 &args[i], 1)))
2802 sibcall_failure = 1;
2803 }
2804
2805 if (args[i].stack)
2806 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
2807 gen_rtx_USE (VOIDmode,
2808 args[i].stack),
2809 call_fusage);
2810 }
2811
2812 /* If we have a parm that is passed in registers but not in memory
2813 and whose alignment does not permit a direct copy into registers,
2814 make a group of pseudos that correspond to each register that we
2815 will later fill. */
2816 if (STRICT_ALIGNMENT)
2817 store_unaligned_arguments_into_pseudos (args, num_actuals);
2818
2819 /* Now store any partially-in-registers parm.
2820 This is the last place a block-move can happen. */
2821 if (reg_parm_seen)
2822 for (i = 0; i < num_actuals; i++)
2823 if (args[i].partial != 0 && ! args[i].pass_on_stack)
2824 {
2825 rtx before_arg = get_last_insn ();
2826
2827 if (store_one_arg (&args[i], argblock, flags,
2828 adjusted_args_size.var != 0,
2829 reg_parm_stack_space)
2830 || (pass == 0
2831 && check_sibcall_argument_overlap (before_arg,
2832 &args[i], 1)))
2833 sibcall_failure = 1;
2834 }
2835
2836 /* If we pushed args in forward order, perform stack alignment
2837 after pushing the last arg. */
2838 if (!PUSH_ARGS_REVERSED && argblock == 0)
2839 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2840 - unadjusted_args_size));
2841
2842 /* If register arguments require space on the stack and stack space
2843 was not preallocated, allocate stack space here for arguments
2844 passed in registers. */
2845 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
2846 && !ACCUMULATE_OUTGOING_ARGS
2847 && must_preallocate == 0 && reg_parm_stack_space > 0)
2848 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
2849
2850 /* Pass the function the address in which to return a
2851 structure value. */
2852 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
2853 {
2854 structure_value_addr
2855 = convert_memory_address (Pmode, structure_value_addr);
2856 emit_move_insn (struct_value,
2857 force_reg (Pmode,
2858 force_operand (structure_value_addr,
2859 NULL_RTX)));
2860
2861 if (REG_P (struct_value))
2862 use_reg (&call_fusage, struct_value);
2863 }
2864
2865 after_args = get_last_insn ();
2866 funexp = prepare_call_address (fndecl, funexp, static_chain_value,
2867 &call_fusage, reg_parm_seen, pass == 0);
2868
2869 load_register_parameters (args, num_actuals, &call_fusage, flags,
2870 pass == 0, &sibcall_failure);
2871
2872 /* Save a pointer to the last insn before the call, so that we can
2873 later safely search backwards to find the CALL_INSN. */
2874 before_call = get_last_insn ();
2875
2876 /* Set up next argument register. For sibling calls on machines
2877 with register windows this should be the incoming register. */
2878 if (pass == 0)
2879 next_arg_reg = targetm.calls.function_incoming_arg (args_so_far,
2880 VOIDmode,
2881 void_type_node,
2882 true);
2883 else
2884 next_arg_reg = targetm.calls.function_arg (args_so_far,
2885 VOIDmode, void_type_node,
2886 true);
2887
2888 /* All arguments and registers used for the call must be set up by
2889 now! */
2890
2891 /* Stack must be properly aligned now. */
2892 gcc_assert (!pass
2893 || !(stack_pointer_delta % preferred_unit_stack_boundary));
2894
2895 /* Generate the actual call instruction. */
2896 emit_call_1 (funexp, exp, fndecl, funtype, unadjusted_args_size,
2897 adjusted_args_size.constant, struct_value_size,
2898 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
2899 flags, args_so_far);
2900
2901 /* If the call setup or the call itself overlaps with anything
2902 of the argument setup we probably clobbered our call address.
2903 In that case we can't do sibcalls. */
2904 if (pass == 0
2905 && check_sibcall_argument_overlap (after_args, 0, 0))
2906 sibcall_failure = 1;
2907
2908 /* If a non-BLKmode value is returned at the most significant end
2909 of a register, shift the register right by the appropriate amount
2910 and update VALREG accordingly. BLKmode values are handled by the
2911 group load/store machinery below. */
2912 if (!structure_value_addr
2913 && !pcc_struct_value
2914 && TYPE_MODE (rettype) != BLKmode
2915 && targetm.calls.return_in_msb (rettype))
2916 {
2917 if (shift_return_value (TYPE_MODE (rettype), false, valreg))
2918 sibcall_failure = 1;
2919 valreg = gen_rtx_REG (TYPE_MODE (rettype), REGNO (valreg));
2920 }
2921
2922 if (pass && (flags & ECF_MALLOC))
2923 {
2924 rtx temp = gen_reg_rtx (GET_MODE (valreg));
2925 rtx last, insns;
2926
2927 /* The return value from a malloc-like function is a pointer. */
2928 if (TREE_CODE (rettype) == POINTER_TYPE)
2929 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
2930
2931 emit_move_insn (temp, valreg);
2932
2933 /* The return value from a malloc-like function can not alias
2934 anything else. */
2935 last = get_last_insn ();
2936 add_reg_note (last, REG_NOALIAS, temp);
2937
2938 /* Write out the sequence. */
2939 insns = get_insns ();
2940 end_sequence ();
2941 emit_insn (insns);
2942 valreg = temp;
2943 }
2944
2945 /* For calls to `setjmp', etc., inform
2946 function.c:setjmp_warnings that it should complain if
2947 nonvolatile values are live. For functions that cannot
2948 return, inform flow that control does not fall through. */
2949
2950 if ((flags & ECF_NORETURN) || pass == 0)
2951 {
2952 /* The barrier must be emitted
2953 immediately after the CALL_INSN. Some ports emit more
2954 than just a CALL_INSN above, so we must search for it here. */
2955
2956 rtx last = get_last_insn ();
2957 while (!CALL_P (last))
2958 {
2959 last = PREV_INSN (last);
2960 /* There was no CALL_INSN? */
2961 gcc_assert (last != before_call);
2962 }
2963
2964 emit_barrier_after (last);
2965
2966 /* Stack adjustments after a noreturn call are dead code.
2967 However when NO_DEFER_POP is in effect, we must preserve
2968 stack_pointer_delta. */
2969 if (inhibit_defer_pop == 0)
2970 {
2971 stack_pointer_delta = old_stack_allocated;
2972 pending_stack_adjust = 0;
2973 }
2974 }
2975
2976 /* If value type not void, return an rtx for the value. */
2977
2978 if (TYPE_MODE (rettype) == VOIDmode
2979 || ignore)
2980 target = const0_rtx;
2981 else if (structure_value_addr)
2982 {
2983 if (target == 0 || !MEM_P (target))
2984 {
2985 target
2986 = gen_rtx_MEM (TYPE_MODE (rettype),
2987 memory_address (TYPE_MODE (rettype),
2988 structure_value_addr));
2989 set_mem_attributes (target, rettype, 1);
2990 }
2991 }
2992 else if (pcc_struct_value)
2993 {
2994 /* This is the special C++ case where we need to
2995 know what the true target was. We take care to
2996 never use this value more than once in one expression. */
2997 target = gen_rtx_MEM (TYPE_MODE (rettype),
2998 copy_to_reg (valreg));
2999 set_mem_attributes (target, rettype, 1);
3000 }
3001 /* Handle calls that return values in multiple non-contiguous locations.
3002 The Irix 6 ABI has examples of this. */
3003 else if (GET_CODE (valreg) == PARALLEL)
3004 {
3005 if (target == 0)
3006 {
3007 /* This will only be assigned once, so it can be readonly. */
3008 tree nt = build_qualified_type (rettype,
3009 (TYPE_QUALS (rettype)
3010 | TYPE_QUAL_CONST));
3011
3012 target = assign_temp (nt, 0, 1, 1);
3013 }
3014
3015 if (! rtx_equal_p (target, valreg))
3016 emit_group_store (target, valreg, rettype,
3017 int_size_in_bytes (rettype));
3018
3019 /* We can not support sibling calls for this case. */
3020 sibcall_failure = 1;
3021 }
3022 else if (target
3023 && GET_MODE (target) == TYPE_MODE (rettype)
3024 && GET_MODE (target) == GET_MODE (valreg))
3025 {
3026 bool may_overlap = false;
3027
3028 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
3029 reg to a plain register. */
3030 if (!REG_P (target) || HARD_REGISTER_P (target))
3031 valreg = avoid_likely_spilled_reg (valreg);
3032
3033 /* If TARGET is a MEM in the argument area, and we have
3034 saved part of the argument area, then we can't store
3035 directly into TARGET as it may get overwritten when we
3036 restore the argument save area below. Don't work too
3037 hard though and simply force TARGET to a register if it
3038 is a MEM; the optimizer is quite likely to sort it out. */
3039 if (ACCUMULATE_OUTGOING_ARGS && pass && MEM_P (target))
3040 for (i = 0; i < num_actuals; i++)
3041 if (args[i].save_area)
3042 {
3043 may_overlap = true;
3044 break;
3045 }
3046
3047 if (may_overlap)
3048 target = copy_to_reg (valreg);
3049 else
3050 {
3051 /* TARGET and VALREG cannot be equal at this point
3052 because the latter would not have
3053 REG_FUNCTION_VALUE_P true, while the former would if
3054 it were referring to the same register.
3055
3056 If they refer to the same register, this move will be
3057 a no-op, except when function inlining is being
3058 done. */
3059 emit_move_insn (target, valreg);
3060
3061 /* If we are setting a MEM, this code must be executed.
3062 Since it is emitted after the call insn, sibcall
3063 optimization cannot be performed in that case. */
3064 if (MEM_P (target))
3065 sibcall_failure = 1;
3066 }
3067 }
3068 else if (TYPE_MODE (rettype) == BLKmode)
3069 {
3070 rtx val = valreg;
3071 if (GET_MODE (val) != BLKmode)
3072 val = avoid_likely_spilled_reg (val);
3073 target = copy_blkmode_from_reg (target, val, rettype);
3074
3075 /* We can not support sibling calls for this case. */
3076 sibcall_failure = 1;
3077 }
3078 else
3079 target = copy_to_reg (avoid_likely_spilled_reg (valreg));
3080
3081 /* If we promoted this return value, make the proper SUBREG.
3082 TARGET might be const0_rtx here, so be careful. */
3083 if (REG_P (target)
3084 && TYPE_MODE (rettype) != BLKmode
3085 && GET_MODE (target) != TYPE_MODE (rettype))
3086 {
3087 tree type = rettype;
3088 int unsignedp = TYPE_UNSIGNED (type);
3089 int offset = 0;
3090 enum machine_mode pmode;
3091
3092 /* Ensure we promote as expected, and get the new unsignedness. */
3093 pmode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
3094 funtype, 1);
3095 gcc_assert (GET_MODE (target) == pmode);
3096
3097 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3098 && (GET_MODE_SIZE (GET_MODE (target))
3099 > GET_MODE_SIZE (TYPE_MODE (type))))
3100 {
3101 offset = GET_MODE_SIZE (GET_MODE (target))
3102 - GET_MODE_SIZE (TYPE_MODE (type));
3103 if (! BYTES_BIG_ENDIAN)
3104 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3105 else if (! WORDS_BIG_ENDIAN)
3106 offset %= UNITS_PER_WORD;
3107 }
3108
3109 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3110 SUBREG_PROMOTED_VAR_P (target) = 1;
3111 SUBREG_PROMOTED_UNSIGNED_SET (target, unsignedp);
3112 }
3113
3114 /* If size of args is variable or this was a constructor call for a stack
3115 argument, restore saved stack-pointer value. */
3116
3117 if (old_stack_level)
3118 {
3119 emit_stack_restore (SAVE_BLOCK, old_stack_level);
3120 stack_pointer_delta = old_stack_pointer_delta;
3121 pending_stack_adjust = old_pending_adj;
3122 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
3123 stack_arg_under_construction = old_stack_arg_under_construction;
3124 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3125 stack_usage_map = initial_stack_usage_map;
3126 sibcall_failure = 1;
3127 }
3128 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3129 {
3130 #ifdef REG_PARM_STACK_SPACE
3131 if (save_area)
3132 restore_fixed_argument_area (save_area, argblock,
3133 high_to_save, low_to_save);
3134 #endif
3135
3136 /* If we saved any argument areas, restore them. */
3137 for (i = 0; i < num_actuals; i++)
3138 if (args[i].save_area)
3139 {
3140 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3141 rtx stack_area
3142 = gen_rtx_MEM (save_mode,
3143 memory_address (save_mode,
3144 XEXP (args[i].stack_slot, 0)));
3145
3146 if (save_mode != BLKmode)
3147 emit_move_insn (stack_area, args[i].save_area);
3148 else
3149 emit_block_move (stack_area, args[i].save_area,
3150 GEN_INT (args[i].locate.size.constant),
3151 BLOCK_OP_CALL_PARM);
3152 }
3153
3154 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3155 stack_usage_map = initial_stack_usage_map;
3156 }
3157
3158 /* If this was alloca, record the new stack level for nonlocal gotos.
3159 Check for the handler slots since we might not have a save area
3160 for non-local gotos. */
3161
3162 if ((flags & ECF_MAY_BE_ALLOCA) && cfun->nonlocal_goto_save_area != 0)
3163 update_nonlocal_goto_save_area ();
3164
3165 /* Free up storage we no longer need. */
3166 for (i = 0; i < num_actuals; ++i)
3167 free (args[i].aligned_regs);
3168
3169 insns = get_insns ();
3170 end_sequence ();
3171
3172 if (pass == 0)
3173 {
3174 tail_call_insns = insns;
3175
3176 /* Restore the pending stack adjustment now that we have
3177 finished generating the sibling call sequence. */
3178
3179 pending_stack_adjust = save_pending_stack_adjust;
3180 stack_pointer_delta = save_stack_pointer_delta;
3181
3182 /* Prepare arg structure for next iteration. */
3183 for (i = 0; i < num_actuals; i++)
3184 {
3185 args[i].value = 0;
3186 args[i].aligned_regs = 0;
3187 args[i].stack = 0;
3188 }
3189
3190 sbitmap_free (stored_args_map);
3191 }
3192 else
3193 {
3194 normal_call_insns = insns;
3195
3196 /* Verify that we've deallocated all the stack we used. */
3197 gcc_assert ((flags & ECF_NORETURN)
3198 || (old_stack_allocated
3199 == stack_pointer_delta - pending_stack_adjust));
3200 }
3201
3202 /* If something prevents making this a sibling call,
3203 zero out the sequence. */
3204 if (sibcall_failure)
3205 tail_call_insns = NULL_RTX;
3206 else
3207 break;
3208 }
3209
3210 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
3211 arguments too, as argument area is now clobbered by the call. */
3212 if (tail_call_insns)
3213 {
3214 emit_insn (tail_call_insns);
3215 crtl->tail_call_emit = true;
3216 }
3217 else
3218 emit_insn (normal_call_insns);
3219
3220 currently_expanding_call--;
3221
3222 free (stack_usage_map_buf);
3223
3224 return target;
3225 }
3226
3227 /* A sibling call sequence invalidates any REG_EQUIV notes made for
3228 this function's incoming arguments.
3229
3230 At the start of RTL generation we know the only REG_EQUIV notes
3231 in the rtl chain are those for incoming arguments, so we can look
3232 for REG_EQUIV notes between the start of the function and the
3233 NOTE_INSN_FUNCTION_BEG.
3234
3235 This is (slight) overkill. We could keep track of the highest
3236 argument we clobber and be more selective in removing notes, but it
3237 does not seem to be worth the effort. */
3238
3239 void
3240 fixup_tail_calls (void)
3241 {
3242 rtx insn;
3243
3244 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3245 {
3246 rtx note;
3247
3248 /* There are never REG_EQUIV notes for the incoming arguments
3249 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
3250 if (NOTE_P (insn)
3251 && NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG)
3252 break;
3253
3254 note = find_reg_note (insn, REG_EQUIV, 0);
3255 if (note)
3256 remove_note (insn, note);
3257 note = find_reg_note (insn, REG_EQUIV, 0);
3258 gcc_assert (!note);
3259 }
3260 }
3261
3262 /* Traverse a list of TYPES and expand all complex types into their
3263 components. */
3264 static tree
3265 split_complex_types (tree types)
3266 {
3267 tree p;
3268
3269 /* Before allocating memory, check for the common case of no complex. */
3270 for (p = types; p; p = TREE_CHAIN (p))
3271 {
3272 tree type = TREE_VALUE (p);
3273 if (TREE_CODE (type) == COMPLEX_TYPE
3274 && targetm.calls.split_complex_arg (type))
3275 goto found;
3276 }
3277 return types;
3278
3279 found:
3280 types = copy_list (types);
3281
3282 for (p = types; p; p = TREE_CHAIN (p))
3283 {
3284 tree complex_type = TREE_VALUE (p);
3285
3286 if (TREE_CODE (complex_type) == COMPLEX_TYPE
3287 && targetm.calls.split_complex_arg (complex_type))
3288 {
3289 tree next, imag;
3290
3291 /* Rewrite complex type with component type. */
3292 TREE_VALUE (p) = TREE_TYPE (complex_type);
3293 next = TREE_CHAIN (p);
3294
3295 /* Add another component type for the imaginary part. */
3296 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
3297 TREE_CHAIN (p) = imag;
3298 TREE_CHAIN (imag) = next;
3299
3300 /* Skip the newly created node. */
3301 p = TREE_CHAIN (p);
3302 }
3303 }
3304
3305 return types;
3306 }
3307 \f
3308 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3309 The RETVAL parameter specifies whether return value needs to be saved, other
3310 parameters are documented in the emit_library_call function below. */
3311
3312 static rtx
3313 emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
3314 enum libcall_type fn_type,
3315 enum machine_mode outmode, int nargs, va_list p)
3316 {
3317 /* Total size in bytes of all the stack-parms scanned so far. */
3318 struct args_size args_size;
3319 /* Size of arguments before any adjustments (such as rounding). */
3320 struct args_size original_args_size;
3321 int argnum;
3322 rtx fun;
3323 /* Todo, choose the correct decl type of orgfun. Sadly this information
3324 isn't present here, so we default to native calling abi here. */
3325 tree fndecl ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
3326 tree fntype ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
3327 int inc;
3328 int count;
3329 rtx argblock = 0;
3330 CUMULATIVE_ARGS args_so_far_v;
3331 cumulative_args_t args_so_far;
3332 struct arg
3333 {
3334 rtx value;
3335 enum machine_mode mode;
3336 rtx reg;
3337 int partial;
3338 struct locate_and_pad_arg_data locate;
3339 rtx save_area;
3340 };
3341 struct arg *argvec;
3342 int old_inhibit_defer_pop = inhibit_defer_pop;
3343 rtx call_fusage = 0;
3344 rtx mem_value = 0;
3345 rtx valreg;
3346 int pcc_struct_value = 0;
3347 int struct_value_size = 0;
3348 int flags;
3349 int reg_parm_stack_space = 0;
3350 int needed;
3351 rtx before_call;
3352 tree tfom; /* type_for_mode (outmode, 0) */
3353
3354 #ifdef REG_PARM_STACK_SPACE
3355 /* Define the boundary of the register parm stack space that needs to be
3356 save, if any. */
3357 int low_to_save = 0, high_to_save = 0;
3358 rtx save_area = 0; /* Place that it is saved. */
3359 #endif
3360
3361 /* Size of the stack reserved for parameter registers. */
3362 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3363 char *initial_stack_usage_map = stack_usage_map;
3364 char *stack_usage_map_buf = NULL;
3365
3366 rtx struct_value = targetm.calls.struct_value_rtx (0, 0);
3367
3368 #ifdef REG_PARM_STACK_SPACE
3369 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3370 #endif
3371
3372 /* By default, library functions can not throw. */
3373 flags = ECF_NOTHROW;
3374
3375 switch (fn_type)
3376 {
3377 case LCT_NORMAL:
3378 break;
3379 case LCT_CONST:
3380 flags |= ECF_CONST;
3381 break;
3382 case LCT_PURE:
3383 flags |= ECF_PURE;
3384 break;
3385 case LCT_NORETURN:
3386 flags |= ECF_NORETURN;
3387 break;
3388 case LCT_THROW:
3389 flags = ECF_NORETURN;
3390 break;
3391 case LCT_RETURNS_TWICE:
3392 flags = ECF_RETURNS_TWICE;
3393 break;
3394 }
3395 fun = orgfun;
3396
3397 /* Ensure current function's preferred stack boundary is at least
3398 what we need. */
3399 if (crtl->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3400 crtl->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3401
3402 /* If this kind of value comes back in memory,
3403 decide where in memory it should come back. */
3404 if (outmode != VOIDmode)
3405 {
3406 tfom = lang_hooks.types.type_for_mode (outmode, 0);
3407 if (aggregate_value_p (tfom, 0))
3408 {
3409 #ifdef PCC_STATIC_STRUCT_RETURN
3410 rtx pointer_reg
3411 = hard_function_value (build_pointer_type (tfom), 0, 0, 0);
3412 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3413 pcc_struct_value = 1;
3414 if (value == 0)
3415 value = gen_reg_rtx (outmode);
3416 #else /* not PCC_STATIC_STRUCT_RETURN */
3417 struct_value_size = GET_MODE_SIZE (outmode);
3418 if (value != 0 && MEM_P (value))
3419 mem_value = value;
3420 else
3421 mem_value = assign_temp (tfom, 0, 1, 1);
3422 #endif
3423 /* This call returns a big structure. */
3424 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
3425 }
3426 }
3427 else
3428 tfom = void_type_node;
3429
3430 /* ??? Unfinished: must pass the memory address as an argument. */
3431
3432 /* Copy all the libcall-arguments out of the varargs data
3433 and into a vector ARGVEC.
3434
3435 Compute how to pass each argument. We only support a very small subset
3436 of the full argument passing conventions to limit complexity here since
3437 library functions shouldn't have many args. */
3438
3439 argvec = XALLOCAVEC (struct arg, nargs + 1);
3440 memset (argvec, 0, (nargs + 1) * sizeof (struct arg));
3441
3442 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3443 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v, outmode, fun);
3444 #else
3445 INIT_CUMULATIVE_ARGS (args_so_far_v, NULL_TREE, fun, 0, nargs);
3446 #endif
3447 args_so_far = pack_cumulative_args (&args_so_far_v);
3448
3449 args_size.constant = 0;
3450 args_size.var = 0;
3451
3452 count = 0;
3453
3454 push_temp_slots ();
3455
3456 /* If there's a structure value address to be passed,
3457 either pass it in the special place, or pass it as an extra argument. */
3458 if (mem_value && struct_value == 0 && ! pcc_struct_value)
3459 {
3460 rtx addr = XEXP (mem_value, 0);
3461
3462 nargs++;
3463
3464 /* Make sure it is a reasonable operand for a move or push insn. */
3465 if (!REG_P (addr) && !MEM_P (addr)
3466 && !(CONSTANT_P (addr)
3467 && targetm.legitimate_constant_p (Pmode, addr)))
3468 addr = force_operand (addr, NULL_RTX);
3469
3470 argvec[count].value = addr;
3471 argvec[count].mode = Pmode;
3472 argvec[count].partial = 0;
3473
3474 argvec[count].reg = targetm.calls.function_arg (args_so_far,
3475 Pmode, NULL_TREE, true);
3476 gcc_assert (targetm.calls.arg_partial_bytes (args_so_far, Pmode,
3477 NULL_TREE, 1) == 0);
3478
3479 locate_and_pad_parm (Pmode, NULL_TREE,
3480 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3481 1,
3482 #else
3483 argvec[count].reg != 0,
3484 #endif
3485 0, NULL_TREE, &args_size, &argvec[count].locate);
3486
3487 if (argvec[count].reg == 0 || argvec[count].partial != 0
3488 || reg_parm_stack_space > 0)
3489 args_size.constant += argvec[count].locate.size.constant;
3490
3491 targetm.calls.function_arg_advance (args_so_far, Pmode, (tree) 0, true);
3492
3493 count++;
3494 }
3495
3496 for (; count < nargs; count++)
3497 {
3498 rtx val = va_arg (p, rtx);
3499 enum machine_mode mode = (enum machine_mode) va_arg (p, int);
3500 int unsigned_p = 0;
3501
3502 /* We cannot convert the arg value to the mode the library wants here;
3503 must do it earlier where we know the signedness of the arg. */
3504 gcc_assert (mode != BLKmode
3505 && (GET_MODE (val) == mode || GET_MODE (val) == VOIDmode));
3506
3507 /* Make sure it is a reasonable operand for a move or push insn. */
3508 if (!REG_P (val) && !MEM_P (val)
3509 && !(CONSTANT_P (val) && targetm.legitimate_constant_p (mode, val)))
3510 val = force_operand (val, NULL_RTX);
3511
3512 if (pass_by_reference (&args_so_far_v, mode, NULL_TREE, 1))
3513 {
3514 rtx slot;
3515 int must_copy
3516 = !reference_callee_copied (&args_so_far_v, mode, NULL_TREE, 1);
3517
3518 /* If this was a CONST function, it is now PURE since it now
3519 reads memory. */
3520 if (flags & ECF_CONST)
3521 {
3522 flags &= ~ECF_CONST;
3523 flags |= ECF_PURE;
3524 }
3525
3526 if (MEM_P (val) && !must_copy)
3527 slot = val;
3528 else
3529 {
3530 slot = assign_temp (lang_hooks.types.type_for_mode (mode, 0),
3531 0, 1, 1);
3532 emit_move_insn (slot, val);
3533 }
3534
3535 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3536 gen_rtx_USE (VOIDmode, slot),
3537 call_fusage);
3538 if (must_copy)
3539 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3540 gen_rtx_CLOBBER (VOIDmode,
3541 slot),
3542 call_fusage);
3543
3544 mode = Pmode;
3545 val = force_operand (XEXP (slot, 0), NULL_RTX);
3546 }
3547
3548 mode = promote_function_mode (NULL_TREE, mode, &unsigned_p, NULL_TREE, 0);
3549 argvec[count].mode = mode;
3550 argvec[count].value = convert_modes (mode, GET_MODE (val), val, unsigned_p);
3551 argvec[count].reg = targetm.calls.function_arg (args_so_far, mode,
3552 NULL_TREE, true);
3553
3554 argvec[count].partial
3555 = targetm.calls.arg_partial_bytes (args_so_far, mode, NULL_TREE, 1);
3556
3557 locate_and_pad_parm (mode, NULL_TREE,
3558 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3559 1,
3560 #else
3561 argvec[count].reg != 0,
3562 #endif
3563 argvec[count].partial,
3564 NULL_TREE, &args_size, &argvec[count].locate);
3565
3566 gcc_assert (!argvec[count].locate.size.var);
3567
3568 if (argvec[count].reg == 0 || argvec[count].partial != 0
3569 || reg_parm_stack_space > 0)
3570 args_size.constant += argvec[count].locate.size.constant;
3571
3572 targetm.calls.function_arg_advance (args_so_far, mode, (tree) 0, true);
3573 }
3574
3575 /* If this machine requires an external definition for library
3576 functions, write one out. */
3577 assemble_external_libcall (fun);
3578
3579 original_args_size = args_size;
3580 args_size.constant = (((args_size.constant
3581 + stack_pointer_delta
3582 + STACK_BYTES - 1)
3583 / STACK_BYTES
3584 * STACK_BYTES)
3585 - stack_pointer_delta);
3586
3587 args_size.constant = MAX (args_size.constant,
3588 reg_parm_stack_space);
3589
3590 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
3591 args_size.constant -= reg_parm_stack_space;
3592
3593 if (args_size.constant > crtl->outgoing_args_size)
3594 crtl->outgoing_args_size = args_size.constant;
3595
3596 if (flag_stack_usage_info && !ACCUMULATE_OUTGOING_ARGS)
3597 {
3598 int pushed = args_size.constant + pending_stack_adjust;
3599 if (pushed > current_function_pushed_stack_size)
3600 current_function_pushed_stack_size = pushed;
3601 }
3602
3603 if (ACCUMULATE_OUTGOING_ARGS)
3604 {
3605 /* Since the stack pointer will never be pushed, it is possible for
3606 the evaluation of a parm to clobber something we have already
3607 written to the stack. Since most function calls on RISC machines
3608 do not use the stack, this is uncommon, but must work correctly.
3609
3610 Therefore, we save any area of the stack that was already written
3611 and that we are using. Here we set up to do this by making a new
3612 stack usage map from the old one.
3613
3614 Another approach might be to try to reorder the argument
3615 evaluations to avoid this conflicting stack usage. */
3616
3617 needed = args_size.constant;
3618
3619 /* Since we will be writing into the entire argument area, the
3620 map must be allocated for its entire size, not just the part that
3621 is the responsibility of the caller. */
3622 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
3623 needed += reg_parm_stack_space;
3624
3625 #ifdef ARGS_GROW_DOWNWARD
3626 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3627 needed + 1);
3628 #else
3629 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3630 needed);
3631 #endif
3632 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
3633 stack_usage_map = stack_usage_map_buf;
3634
3635 if (initial_highest_arg_in_use)
3636 memcpy (stack_usage_map, initial_stack_usage_map,
3637 initial_highest_arg_in_use);
3638
3639 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3640 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3641 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3642 needed = 0;
3643
3644 /* We must be careful to use virtual regs before they're instantiated,
3645 and real regs afterwards. Loop optimization, for example, can create
3646 new libcalls after we've instantiated the virtual regs, and if we
3647 use virtuals anyway, they won't match the rtl patterns. */
3648
3649 if (virtuals_instantiated)
3650 argblock = plus_constant (stack_pointer_rtx, STACK_POINTER_OFFSET);
3651 else
3652 argblock = virtual_outgoing_args_rtx;
3653 }
3654 else
3655 {
3656 if (!PUSH_ARGS)
3657 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3658 }
3659
3660 /* If we push args individually in reverse order, perform stack alignment
3661 before the first push (the last arg). */
3662 if (argblock == 0 && PUSH_ARGS_REVERSED)
3663 anti_adjust_stack (GEN_INT (args_size.constant
3664 - original_args_size.constant));
3665
3666 if (PUSH_ARGS_REVERSED)
3667 {
3668 inc = -1;
3669 argnum = nargs - 1;
3670 }
3671 else
3672 {
3673 inc = 1;
3674 argnum = 0;
3675 }
3676
3677 #ifdef REG_PARM_STACK_SPACE
3678 if (ACCUMULATE_OUTGOING_ARGS)
3679 {
3680 /* The argument list is the property of the called routine and it
3681 may clobber it. If the fixed area has been used for previous
3682 parameters, we must save and restore it. */
3683 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3684 &low_to_save, &high_to_save);
3685 }
3686 #endif
3687
3688 /* Push the args that need to be pushed. */
3689
3690 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3691 are to be pushed. */
3692 for (count = 0; count < nargs; count++, argnum += inc)
3693 {
3694 enum machine_mode mode = argvec[argnum].mode;
3695 rtx val = argvec[argnum].value;
3696 rtx reg = argvec[argnum].reg;
3697 int partial = argvec[argnum].partial;
3698 unsigned int parm_align = argvec[argnum].locate.boundary;
3699 int lower_bound = 0, upper_bound = 0, i;
3700
3701 if (! (reg != 0 && partial == 0))
3702 {
3703 rtx use;
3704
3705 if (ACCUMULATE_OUTGOING_ARGS)
3706 {
3707 /* If this is being stored into a pre-allocated, fixed-size,
3708 stack area, save any previous data at that location. */
3709
3710 #ifdef ARGS_GROW_DOWNWARD
3711 /* stack_slot is negative, but we want to index stack_usage_map
3712 with positive values. */
3713 upper_bound = -argvec[argnum].locate.slot_offset.constant + 1;
3714 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
3715 #else
3716 lower_bound = argvec[argnum].locate.slot_offset.constant;
3717 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
3718 #endif
3719
3720 i = lower_bound;
3721 /* Don't worry about things in the fixed argument area;
3722 it has already been saved. */
3723 if (i < reg_parm_stack_space)
3724 i = reg_parm_stack_space;
3725 while (i < upper_bound && stack_usage_map[i] == 0)
3726 i++;
3727
3728 if (i < upper_bound)
3729 {
3730 /* We need to make a save area. */
3731 unsigned int size
3732 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
3733 enum machine_mode save_mode
3734 = mode_for_size (size, MODE_INT, 1);
3735 rtx adr
3736 = plus_constant (argblock,
3737 argvec[argnum].locate.offset.constant);
3738 rtx stack_area
3739 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
3740
3741 if (save_mode == BLKmode)
3742 {
3743 argvec[argnum].save_area
3744 = assign_stack_temp (BLKmode,
3745 argvec[argnum].locate.size.constant,
3746 0);
3747
3748 emit_block_move (validize_mem (argvec[argnum].save_area),
3749 stack_area,
3750 GEN_INT (argvec[argnum].locate.size.constant),
3751 BLOCK_OP_CALL_PARM);
3752 }
3753 else
3754 {
3755 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3756
3757 emit_move_insn (argvec[argnum].save_area, stack_area);
3758 }
3759 }
3760 }
3761
3762 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, parm_align,
3763 partial, reg, 0, argblock,
3764 GEN_INT (argvec[argnum].locate.offset.constant),
3765 reg_parm_stack_space,
3766 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad));
3767
3768 /* Now mark the segment we just used. */
3769 if (ACCUMULATE_OUTGOING_ARGS)
3770 for (i = lower_bound; i < upper_bound; i++)
3771 stack_usage_map[i] = 1;
3772
3773 NO_DEFER_POP;
3774
3775 /* Indicate argument access so that alias.c knows that these
3776 values are live. */
3777 if (argblock)
3778 use = plus_constant (argblock,
3779 argvec[argnum].locate.offset.constant);
3780 else
3781 /* When arguments are pushed, trying to tell alias.c where
3782 exactly this argument is won't work, because the
3783 auto-increment causes confusion. So we merely indicate
3784 that we access something with a known mode somewhere on
3785 the stack. */
3786 use = gen_rtx_PLUS (Pmode, virtual_outgoing_args_rtx,
3787 gen_rtx_SCRATCH (Pmode));
3788 use = gen_rtx_MEM (argvec[argnum].mode, use);
3789 use = gen_rtx_USE (VOIDmode, use);
3790 call_fusage = gen_rtx_EXPR_LIST (VOIDmode, use, call_fusage);
3791 }
3792 }
3793
3794 /* If we pushed args in forward order, perform stack alignment
3795 after pushing the last arg. */
3796 if (argblock == 0 && !PUSH_ARGS_REVERSED)
3797 anti_adjust_stack (GEN_INT (args_size.constant
3798 - original_args_size.constant));
3799
3800 if (PUSH_ARGS_REVERSED)
3801 argnum = nargs - 1;
3802 else
3803 argnum = 0;
3804
3805 fun = prepare_call_address (NULL, fun, NULL, &call_fusage, 0, 0);
3806
3807 /* Now load any reg parms into their regs. */
3808
3809 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3810 are to be pushed. */
3811 for (count = 0; count < nargs; count++, argnum += inc)
3812 {
3813 enum machine_mode mode = argvec[argnum].mode;
3814 rtx val = argvec[argnum].value;
3815 rtx reg = argvec[argnum].reg;
3816 int partial = argvec[argnum].partial;
3817
3818 /* Handle calls that pass values in multiple non-contiguous
3819 locations. The PA64 has examples of this for library calls. */
3820 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3821 emit_group_load (reg, val, NULL_TREE, GET_MODE_SIZE (mode));
3822 else if (reg != 0 && partial == 0)
3823 emit_move_insn (reg, val);
3824
3825 NO_DEFER_POP;
3826 }
3827
3828 /* Any regs containing parms remain in use through the call. */
3829 for (count = 0; count < nargs; count++)
3830 {
3831 rtx reg = argvec[count].reg;
3832 if (reg != 0 && GET_CODE (reg) == PARALLEL)
3833 use_group_regs (&call_fusage, reg);
3834 else if (reg != 0)
3835 {
3836 int partial = argvec[count].partial;
3837 if (partial)
3838 {
3839 int nregs;
3840 gcc_assert (partial % UNITS_PER_WORD == 0);
3841 nregs = partial / UNITS_PER_WORD;
3842 use_regs (&call_fusage, REGNO (reg), nregs);
3843 }
3844 else
3845 use_reg (&call_fusage, reg);
3846 }
3847 }
3848
3849 /* Pass the function the address in which to return a structure value. */
3850 if (mem_value != 0 && struct_value != 0 && ! pcc_struct_value)
3851 {
3852 emit_move_insn (struct_value,
3853 force_reg (Pmode,
3854 force_operand (XEXP (mem_value, 0),
3855 NULL_RTX)));
3856 if (REG_P (struct_value))
3857 use_reg (&call_fusage, struct_value);
3858 }
3859
3860 /* Don't allow popping to be deferred, since then
3861 cse'ing of library calls could delete a call and leave the pop. */
3862 NO_DEFER_POP;
3863 valreg = (mem_value == 0 && outmode != VOIDmode
3864 ? hard_libcall_value (outmode, orgfun) : NULL_RTX);
3865
3866 /* Stack must be properly aligned now. */
3867 gcc_assert (!(stack_pointer_delta
3868 & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1)));
3869
3870 before_call = get_last_insn ();
3871
3872 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
3873 will set inhibit_defer_pop to that value. */
3874 /* The return type is needed to decide how many bytes the function pops.
3875 Signedness plays no role in that, so for simplicity, we pretend it's
3876 always signed. We also assume that the list of arguments passed has
3877 no impact, so we pretend it is unknown. */
3878
3879 emit_call_1 (fun, NULL,
3880 get_identifier (XSTR (orgfun, 0)),
3881 build_function_type (tfom, NULL_TREE),
3882 original_args_size.constant, args_size.constant,
3883 struct_value_size,
3884 targetm.calls.function_arg (args_so_far,
3885 VOIDmode, void_type_node, true),
3886 valreg,
3887 old_inhibit_defer_pop + 1, call_fusage, flags, args_so_far);
3888
3889 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
3890 that it should complain if nonvolatile values are live. For
3891 functions that cannot return, inform flow that control does not
3892 fall through. */
3893
3894 if (flags & ECF_NORETURN)
3895 {
3896 /* The barrier note must be emitted
3897 immediately after the CALL_INSN. Some ports emit more than
3898 just a CALL_INSN above, so we must search for it here. */
3899
3900 rtx last = get_last_insn ();
3901 while (!CALL_P (last))
3902 {
3903 last = PREV_INSN (last);
3904 /* There was no CALL_INSN? */
3905 gcc_assert (last != before_call);
3906 }
3907
3908 emit_barrier_after (last);
3909 }
3910
3911 /* Now restore inhibit_defer_pop to its actual original value. */
3912 OK_DEFER_POP;
3913
3914 pop_temp_slots ();
3915
3916 /* Copy the value to the right place. */
3917 if (outmode != VOIDmode && retval)
3918 {
3919 if (mem_value)
3920 {
3921 if (value == 0)
3922 value = mem_value;
3923 if (value != mem_value)
3924 emit_move_insn (value, mem_value);
3925 }
3926 else if (GET_CODE (valreg) == PARALLEL)
3927 {
3928 if (value == 0)
3929 value = gen_reg_rtx (outmode);
3930 emit_group_store (value, valreg, NULL_TREE, GET_MODE_SIZE (outmode));
3931 }
3932 else
3933 {
3934 /* Convert to the proper mode if a promotion has been active. */
3935 if (GET_MODE (valreg) != outmode)
3936 {
3937 int unsignedp = TYPE_UNSIGNED (tfom);
3938
3939 gcc_assert (promote_function_mode (tfom, outmode, &unsignedp,
3940 fndecl ? TREE_TYPE (fndecl) : fntype, 1)
3941 == GET_MODE (valreg));
3942 valreg = convert_modes (outmode, GET_MODE (valreg), valreg, 0);
3943 }
3944
3945 if (value != 0)
3946 emit_move_insn (value, valreg);
3947 else
3948 value = valreg;
3949 }
3950 }
3951
3952 if (ACCUMULATE_OUTGOING_ARGS)
3953 {
3954 #ifdef REG_PARM_STACK_SPACE
3955 if (save_area)
3956 restore_fixed_argument_area (save_area, argblock,
3957 high_to_save, low_to_save);
3958 #endif
3959
3960 /* If we saved any argument areas, restore them. */
3961 for (count = 0; count < nargs; count++)
3962 if (argvec[count].save_area)
3963 {
3964 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
3965 rtx adr = plus_constant (argblock,
3966 argvec[count].locate.offset.constant);
3967 rtx stack_area = gen_rtx_MEM (save_mode,
3968 memory_address (save_mode, adr));
3969
3970 if (save_mode == BLKmode)
3971 emit_block_move (stack_area,
3972 validize_mem (argvec[count].save_area),
3973 GEN_INT (argvec[count].locate.size.constant),
3974 BLOCK_OP_CALL_PARM);
3975 else
3976 emit_move_insn (stack_area, argvec[count].save_area);
3977 }
3978
3979 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3980 stack_usage_map = initial_stack_usage_map;
3981 }
3982
3983 free (stack_usage_map_buf);
3984
3985 return value;
3986
3987 }
3988 \f
3989 /* Output a library call to function FUN (a SYMBOL_REF rtx)
3990 (emitting the queue unless NO_QUEUE is nonzero),
3991 for a value of mode OUTMODE,
3992 with NARGS different arguments, passed as alternating rtx values
3993 and machine_modes to convert them to.
3994
3995 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
3996 `const' calls, LCT_PURE for `pure' calls, or other LCT_ value for
3997 other types of library calls. */
3998
3999 void
4000 emit_library_call (rtx orgfun, enum libcall_type fn_type,
4001 enum machine_mode outmode, int nargs, ...)
4002 {
4003 va_list p;
4004
4005 va_start (p, nargs);
4006 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4007 va_end (p);
4008 }
4009 \f
4010 /* Like emit_library_call except that an extra argument, VALUE,
4011 comes second and says where to store the result.
4012 (If VALUE is zero, this function chooses a convenient way
4013 to return the value.
4014
4015 This function returns an rtx for where the value is to be found.
4016 If VALUE is nonzero, VALUE is returned. */
4017
4018 rtx
4019 emit_library_call_value (rtx orgfun, rtx value,
4020 enum libcall_type fn_type,
4021 enum machine_mode outmode, int nargs, ...)
4022 {
4023 rtx result;
4024 va_list p;
4025
4026 va_start (p, nargs);
4027 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4028 nargs, p);
4029 va_end (p);
4030
4031 return result;
4032 }
4033 \f
4034 /* Store a single argument for a function call
4035 into the register or memory area where it must be passed.
4036 *ARG describes the argument value and where to pass it.
4037
4038 ARGBLOCK is the address of the stack-block for all the arguments,
4039 or 0 on a machine where arguments are pushed individually.
4040
4041 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4042 so must be careful about how the stack is used.
4043
4044 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4045 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4046 that we need not worry about saving and restoring the stack.
4047
4048 FNDECL is the declaration of the function we are calling.
4049
4050 Return nonzero if this arg should cause sibcall failure,
4051 zero otherwise. */
4052
4053 static int
4054 store_one_arg (struct arg_data *arg, rtx argblock, int flags,
4055 int variable_size ATTRIBUTE_UNUSED, int reg_parm_stack_space)
4056 {
4057 tree pval = arg->tree_value;
4058 rtx reg = 0;
4059 int partial = 0;
4060 int used = 0;
4061 int i, lower_bound = 0, upper_bound = 0;
4062 int sibcall_failure = 0;
4063
4064 if (TREE_CODE (pval) == ERROR_MARK)
4065 return 1;
4066
4067 /* Push a new temporary level for any temporaries we make for
4068 this argument. */
4069 push_temp_slots ();
4070
4071 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4072 {
4073 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4074 save any previous data at that location. */
4075 if (argblock && ! variable_size && arg->stack)
4076 {
4077 #ifdef ARGS_GROW_DOWNWARD
4078 /* stack_slot is negative, but we want to index stack_usage_map
4079 with positive values. */
4080 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4081 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4082 else
4083 upper_bound = 0;
4084
4085 lower_bound = upper_bound - arg->locate.size.constant;
4086 #else
4087 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4088 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4089 else
4090 lower_bound = 0;
4091
4092 upper_bound = lower_bound + arg->locate.size.constant;
4093 #endif
4094
4095 i = lower_bound;
4096 /* Don't worry about things in the fixed argument area;
4097 it has already been saved. */
4098 if (i < reg_parm_stack_space)
4099 i = reg_parm_stack_space;
4100 while (i < upper_bound && stack_usage_map[i] == 0)
4101 i++;
4102
4103 if (i < upper_bound)
4104 {
4105 /* We need to make a save area. */
4106 unsigned int size = arg->locate.size.constant * BITS_PER_UNIT;
4107 enum machine_mode save_mode = mode_for_size (size, MODE_INT, 1);
4108 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
4109 rtx stack_area = gen_rtx_MEM (save_mode, adr);
4110
4111 if (save_mode == BLKmode)
4112 {
4113 tree ot = TREE_TYPE (arg->tree_value);
4114 tree nt = build_qualified_type (ot, (TYPE_QUALS (ot)
4115 | TYPE_QUAL_CONST));
4116
4117 arg->save_area = assign_temp (nt, 0, 1, 1);
4118 preserve_temp_slots (arg->save_area);
4119 emit_block_move (validize_mem (arg->save_area), stack_area,
4120 GEN_INT (arg->locate.size.constant),
4121 BLOCK_OP_CALL_PARM);
4122 }
4123 else
4124 {
4125 arg->save_area = gen_reg_rtx (save_mode);
4126 emit_move_insn (arg->save_area, stack_area);
4127 }
4128 }
4129 }
4130 }
4131
4132 /* If this isn't going to be placed on both the stack and in registers,
4133 set up the register and number of words. */
4134 if (! arg->pass_on_stack)
4135 {
4136 if (flags & ECF_SIBCALL)
4137 reg = arg->tail_call_reg;
4138 else
4139 reg = arg->reg;
4140 partial = arg->partial;
4141 }
4142
4143 /* Being passed entirely in a register. We shouldn't be called in
4144 this case. */
4145 gcc_assert (reg == 0 || partial != 0);
4146
4147 /* If this arg needs special alignment, don't load the registers
4148 here. */
4149 if (arg->n_aligned_regs != 0)
4150 reg = 0;
4151
4152 /* If this is being passed partially in a register, we can't evaluate
4153 it directly into its stack slot. Otherwise, we can. */
4154 if (arg->value == 0)
4155 {
4156 /* stack_arg_under_construction is nonzero if a function argument is
4157 being evaluated directly into the outgoing argument list and
4158 expand_call must take special action to preserve the argument list
4159 if it is called recursively.
4160
4161 For scalar function arguments stack_usage_map is sufficient to
4162 determine which stack slots must be saved and restored. Scalar
4163 arguments in general have pass_on_stack == 0.
4164
4165 If this argument is initialized by a function which takes the
4166 address of the argument (a C++ constructor or a C function
4167 returning a BLKmode structure), then stack_usage_map is
4168 insufficient and expand_call must push the stack around the
4169 function call. Such arguments have pass_on_stack == 1.
4170
4171 Note that it is always safe to set stack_arg_under_construction,
4172 but this generates suboptimal code if set when not needed. */
4173
4174 if (arg->pass_on_stack)
4175 stack_arg_under_construction++;
4176
4177 arg->value = expand_expr (pval,
4178 (partial
4179 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4180 ? NULL_RTX : arg->stack,
4181 VOIDmode, EXPAND_STACK_PARM);
4182
4183 /* If we are promoting object (or for any other reason) the mode
4184 doesn't agree, convert the mode. */
4185
4186 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4187 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4188 arg->value, arg->unsignedp);
4189
4190 if (arg->pass_on_stack)
4191 stack_arg_under_construction--;
4192 }
4193
4194 /* Check for overlap with already clobbered argument area. */
4195 if ((flags & ECF_SIBCALL)
4196 && MEM_P (arg->value)
4197 && mem_overlaps_already_clobbered_arg_p (XEXP (arg->value, 0),
4198 arg->locate.size.constant))
4199 sibcall_failure = 1;
4200
4201 /* Don't allow anything left on stack from computation
4202 of argument to alloca. */
4203 if (flags & ECF_MAY_BE_ALLOCA)
4204 do_pending_stack_adjust ();
4205
4206 if (arg->value == arg->stack)
4207 /* If the value is already in the stack slot, we are done. */
4208 ;
4209 else if (arg->mode != BLKmode)
4210 {
4211 int size;
4212 unsigned int parm_align;
4213
4214 /* Argument is a scalar, not entirely passed in registers.
4215 (If part is passed in registers, arg->partial says how much
4216 and emit_push_insn will take care of putting it there.)
4217
4218 Push it, and if its size is less than the
4219 amount of space allocated to it,
4220 also bump stack pointer by the additional space.
4221 Note that in C the default argument promotions
4222 will prevent such mismatches. */
4223
4224 size = GET_MODE_SIZE (arg->mode);
4225 /* Compute how much space the push instruction will push.
4226 On many machines, pushing a byte will advance the stack
4227 pointer by a halfword. */
4228 #ifdef PUSH_ROUNDING
4229 size = PUSH_ROUNDING (size);
4230 #endif
4231 used = size;
4232
4233 /* Compute how much space the argument should get:
4234 round up to a multiple of the alignment for arguments. */
4235 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4236 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4237 / (PARM_BOUNDARY / BITS_PER_UNIT))
4238 * (PARM_BOUNDARY / BITS_PER_UNIT));
4239
4240 /* Compute the alignment of the pushed argument. */
4241 parm_align = arg->locate.boundary;
4242 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4243 {
4244 int pad = used - size;
4245 if (pad)
4246 {
4247 unsigned int pad_align = (pad & -pad) * BITS_PER_UNIT;
4248 parm_align = MIN (parm_align, pad_align);
4249 }
4250 }
4251
4252 /* This isn't already where we want it on the stack, so put it there.
4253 This can either be done with push or copy insns. */
4254 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
4255 parm_align, partial, reg, used - size, argblock,
4256 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4257 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4258
4259 /* Unless this is a partially-in-register argument, the argument is now
4260 in the stack. */
4261 if (partial == 0)
4262 arg->value = arg->stack;
4263 }
4264 else
4265 {
4266 /* BLKmode, at least partly to be pushed. */
4267
4268 unsigned int parm_align;
4269 int excess;
4270 rtx size_rtx;
4271
4272 /* Pushing a nonscalar.
4273 If part is passed in registers, PARTIAL says how much
4274 and emit_push_insn will take care of putting it there. */
4275
4276 /* Round its size up to a multiple
4277 of the allocation unit for arguments. */
4278
4279 if (arg->locate.size.var != 0)
4280 {
4281 excess = 0;
4282 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
4283 }
4284 else
4285 {
4286 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
4287 for BLKmode is careful to avoid it. */
4288 excess = (arg->locate.size.constant
4289 - int_size_in_bytes (TREE_TYPE (pval))
4290 + partial);
4291 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
4292 NULL_RTX, TYPE_MODE (sizetype),
4293 EXPAND_NORMAL);
4294 }
4295
4296 parm_align = arg->locate.boundary;
4297
4298 /* When an argument is padded down, the block is aligned to
4299 PARM_BOUNDARY, but the actual argument isn't. */
4300 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4301 {
4302 if (arg->locate.size.var)
4303 parm_align = BITS_PER_UNIT;
4304 else if (excess)
4305 {
4306 unsigned int excess_align = (excess & -excess) * BITS_PER_UNIT;
4307 parm_align = MIN (parm_align, excess_align);
4308 }
4309 }
4310
4311 if ((flags & ECF_SIBCALL) && MEM_P (arg->value))
4312 {
4313 /* emit_push_insn might not work properly if arg->value and
4314 argblock + arg->locate.offset areas overlap. */
4315 rtx x = arg->value;
4316 int i = 0;
4317
4318 if (XEXP (x, 0) == crtl->args.internal_arg_pointer
4319 || (GET_CODE (XEXP (x, 0)) == PLUS
4320 && XEXP (XEXP (x, 0), 0) ==
4321 crtl->args.internal_arg_pointer
4322 && CONST_INT_P (XEXP (XEXP (x, 0), 1))))
4323 {
4324 if (XEXP (x, 0) != crtl->args.internal_arg_pointer)
4325 i = INTVAL (XEXP (XEXP (x, 0), 1));
4326
4327 /* expand_call should ensure this. */
4328 gcc_assert (!arg->locate.offset.var
4329 && arg->locate.size.var == 0
4330 && CONST_INT_P (size_rtx));
4331
4332 if (arg->locate.offset.constant > i)
4333 {
4334 if (arg->locate.offset.constant < i + INTVAL (size_rtx))
4335 sibcall_failure = 1;
4336 }
4337 else if (arg->locate.offset.constant < i)
4338 {
4339 /* Use arg->locate.size.constant instead of size_rtx
4340 because we only care about the part of the argument
4341 on the stack. */
4342 if (i < (arg->locate.offset.constant
4343 + arg->locate.size.constant))
4344 sibcall_failure = 1;
4345 }
4346 else
4347 {
4348 /* Even though they appear to be at the same location,
4349 if part of the outgoing argument is in registers,
4350 they aren't really at the same location. Check for
4351 this by making sure that the incoming size is the
4352 same as the outgoing size. */
4353 if (arg->locate.size.constant != INTVAL (size_rtx))
4354 sibcall_failure = 1;
4355 }
4356 }
4357 }
4358
4359 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4360 parm_align, partial, reg, excess, argblock,
4361 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4362 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4363
4364 /* Unless this is a partially-in-register argument, the argument is now
4365 in the stack.
4366
4367 ??? Unlike the case above, in which we want the actual
4368 address of the data, so that we can load it directly into a
4369 register, here we want the address of the stack slot, so that
4370 it's properly aligned for word-by-word copying or something
4371 like that. It's not clear that this is always correct. */
4372 if (partial == 0)
4373 arg->value = arg->stack_slot;
4374 }
4375
4376 if (arg->reg && GET_CODE (arg->reg) == PARALLEL)
4377 {
4378 tree type = TREE_TYPE (arg->tree_value);
4379 arg->parallel_value
4380 = emit_group_load_into_temps (arg->reg, arg->value, type,
4381 int_size_in_bytes (type));
4382 }
4383
4384 /* Mark all slots this store used. */
4385 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
4386 && argblock && ! variable_size && arg->stack)
4387 for (i = lower_bound; i < upper_bound; i++)
4388 stack_usage_map[i] = 1;
4389
4390 /* Once we have pushed something, pops can't safely
4391 be deferred during the rest of the arguments. */
4392 NO_DEFER_POP;
4393
4394 /* Free any temporary slots made in processing this argument. Show
4395 that we might have taken the address of something and pushed that
4396 as an operand. */
4397 preserve_temp_slots (NULL_RTX);
4398 free_temp_slots ();
4399 pop_temp_slots ();
4400
4401 return sibcall_failure;
4402 }
4403
4404 /* Nonzero if we do not know how to pass TYPE solely in registers. */
4405
4406 bool
4407 must_pass_in_stack_var_size (enum machine_mode mode ATTRIBUTE_UNUSED,
4408 const_tree type)
4409 {
4410 if (!type)
4411 return false;
4412
4413 /* If the type has variable size... */
4414 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4415 return true;
4416
4417 /* If the type is marked as addressable (it is required
4418 to be constructed into the stack)... */
4419 if (TREE_ADDRESSABLE (type))
4420 return true;
4421
4422 return false;
4423 }
4424
4425 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
4426 takes trailing padding of a structure into account. */
4427 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
4428
4429 bool
4430 must_pass_in_stack_var_size_or_pad (enum machine_mode mode, const_tree type)
4431 {
4432 if (!type)
4433 return false;
4434
4435 /* If the type has variable size... */
4436 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4437 return true;
4438
4439 /* If the type is marked as addressable (it is required
4440 to be constructed into the stack)... */
4441 if (TREE_ADDRESSABLE (type))
4442 return true;
4443
4444 /* If the padding and mode of the type is such that a copy into
4445 a register would put it into the wrong part of the register. */
4446 if (mode == BLKmode
4447 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
4448 && (FUNCTION_ARG_PADDING (mode, type)
4449 == (BYTES_BIG_ENDIAN ? upward : downward)))
4450 return true;
4451
4452 return false;
4453 }