re PR target/69140 (stack alignment + O1 breaks with Microsoft ABI)
[gcc.git] / gcc / calls.c
1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989-2016 Free Software Foundation, Inc.
3
4 This file is part of GCC.
5
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
19
20 #include "config.h"
21 #include "system.h"
22 #include "coretypes.h"
23 #include "backend.h"
24 #include "target.h"
25 #include "rtl.h"
26 #include "tree.h"
27 #include "gimple.h"
28 #include "predict.h"
29 #include "tm_p.h"
30 #include "stringpool.h"
31 #include "expmed.h"
32 #include "optabs.h"
33 #include "emit-rtl.h"
34 #include "cgraph.h"
35 #include "diagnostic-core.h"
36 #include "fold-const.h"
37 #include "stor-layout.h"
38 #include "varasm.h"
39 #include "internal-fn.h"
40 #include "dojump.h"
41 #include "explow.h"
42 #include "calls.h"
43 #include "expr.h"
44 #include "output.h"
45 #include "langhooks.h"
46 #include "except.h"
47 #include "dbgcnt.h"
48 #include "rtl-iter.h"
49 #include "tree-chkp.h"
50 #include "rtl-chkp.h"
51
52
53 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
54 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
55
56 /* Data structure and subroutines used within expand_call. */
57
58 struct arg_data
59 {
60 /* Tree node for this argument. */
61 tree tree_value;
62 /* Mode for value; TYPE_MODE unless promoted. */
63 machine_mode mode;
64 /* Current RTL value for argument, or 0 if it isn't precomputed. */
65 rtx value;
66 /* Initially-compute RTL value for argument; only for const functions. */
67 rtx initial_value;
68 /* Register to pass this argument in, 0 if passed on stack, or an
69 PARALLEL if the arg is to be copied into multiple non-contiguous
70 registers. */
71 rtx reg;
72 /* Register to pass this argument in when generating tail call sequence.
73 This is not the same register as for normal calls on machines with
74 register windows. */
75 rtx tail_call_reg;
76 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
77 form for emit_group_move. */
78 rtx parallel_value;
79 /* If value is passed in neither reg nor stack, this field holds a number
80 of a special slot to be used. */
81 rtx special_slot;
82 /* For pointer bounds hold an index of parm bounds are bound to. -1 if
83 there is no such pointer. */
84 int pointer_arg;
85 /* If pointer_arg refers a structure, then pointer_offset holds an offset
86 of a pointer in this structure. */
87 int pointer_offset;
88 /* If REG was promoted from the actual mode of the argument expression,
89 indicates whether the promotion is sign- or zero-extended. */
90 int unsignedp;
91 /* Number of bytes to put in registers. 0 means put the whole arg
92 in registers. Also 0 if not passed in registers. */
93 int partial;
94 /* Nonzero if argument must be passed on stack.
95 Note that some arguments may be passed on the stack
96 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
97 pass_on_stack identifies arguments that *cannot* go in registers. */
98 int pass_on_stack;
99 /* Some fields packaged up for locate_and_pad_parm. */
100 struct locate_and_pad_arg_data locate;
101 /* Location on the stack at which parameter should be stored. The store
102 has already been done if STACK == VALUE. */
103 rtx stack;
104 /* Location on the stack of the start of this argument slot. This can
105 differ from STACK if this arg pads downward. This location is known
106 to be aligned to TARGET_FUNCTION_ARG_BOUNDARY. */
107 rtx stack_slot;
108 /* Place that this stack area has been saved, if needed. */
109 rtx save_area;
110 /* If an argument's alignment does not permit direct copying into registers,
111 copy in smaller-sized pieces into pseudos. These are stored in a
112 block pointed to by this field. The next field says how many
113 word-sized pseudos we made. */
114 rtx *aligned_regs;
115 int n_aligned_regs;
116 };
117
118 /* A vector of one char per byte of stack space. A byte if nonzero if
119 the corresponding stack location has been used.
120 This vector is used to prevent a function call within an argument from
121 clobbering any stack already set up. */
122 static char *stack_usage_map;
123
124 /* Size of STACK_USAGE_MAP. */
125 static int highest_outgoing_arg_in_use;
126
127 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
128 stack location's tail call argument has been already stored into the stack.
129 This bitmap is used to prevent sibling call optimization if function tries
130 to use parent's incoming argument slots when they have been already
131 overwritten with tail call arguments. */
132 static sbitmap stored_args_map;
133
134 /* stack_arg_under_construction is nonzero when an argument may be
135 initialized with a constructor call (including a C function that
136 returns a BLKmode struct) and expand_call must take special action
137 to make sure the object being constructed does not overlap the
138 argument list for the constructor call. */
139 static int stack_arg_under_construction;
140
141 static void emit_call_1 (rtx, tree, tree, tree, HOST_WIDE_INT, HOST_WIDE_INT,
142 HOST_WIDE_INT, rtx, rtx, int, rtx, int,
143 cumulative_args_t);
144 static void precompute_register_parameters (int, struct arg_data *, int *);
145 static void store_bounds (struct arg_data *, struct arg_data *);
146 static int store_one_arg (struct arg_data *, rtx, int, int, int);
147 static void store_unaligned_arguments_into_pseudos (struct arg_data *, int);
148 static int finalize_must_preallocate (int, int, struct arg_data *,
149 struct args_size *);
150 static void precompute_arguments (int, struct arg_data *);
151 static int compute_argument_block_size (int, struct args_size *, tree, tree, int);
152 static void initialize_argument_information (int, struct arg_data *,
153 struct args_size *, int,
154 tree, tree,
155 tree, tree, cumulative_args_t, int,
156 rtx *, int *, int *, int *,
157 bool *, bool);
158 static void compute_argument_addresses (struct arg_data *, rtx, int);
159 static rtx rtx_for_function_call (tree, tree);
160 static void load_register_parameters (struct arg_data *, int, rtx *, int,
161 int, int *);
162 static rtx emit_library_call_value_1 (int, rtx, rtx, enum libcall_type,
163 machine_mode, int, va_list);
164 static int special_function_p (const_tree, int);
165 static int check_sibcall_argument_overlap_1 (rtx);
166 static int check_sibcall_argument_overlap (rtx_insn *, struct arg_data *, int);
167
168 static int combine_pending_stack_adjustment_and_call (int, struct args_size *,
169 unsigned int);
170 static tree split_complex_types (tree);
171
172 #ifdef REG_PARM_STACK_SPACE
173 static rtx save_fixed_argument_area (int, rtx, int *, int *);
174 static void restore_fixed_argument_area (rtx, rtx, int, int);
175 #endif
176 \f
177 /* Force FUNEXP into a form suitable for the address of a CALL,
178 and return that as an rtx. Also load the static chain register
179 if FNDECL is a nested function.
180
181 CALL_FUSAGE points to a variable holding the prospective
182 CALL_INSN_FUNCTION_USAGE information. */
183
184 rtx
185 prepare_call_address (tree fndecl_or_type, rtx funexp, rtx static_chain_value,
186 rtx *call_fusage, int reg_parm_seen, int sibcallp)
187 {
188 /* Make a valid memory address and copy constants through pseudo-regs,
189 but not for a constant address if -fno-function-cse. */
190 if (GET_CODE (funexp) != SYMBOL_REF)
191 /* If we are using registers for parameters, force the
192 function address into a register now. */
193 funexp = ((reg_parm_seen
194 && targetm.small_register_classes_for_mode_p (FUNCTION_MODE))
195 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
196 : memory_address (FUNCTION_MODE, funexp));
197 else if (! sibcallp)
198 {
199 if (!NO_FUNCTION_CSE && optimize && ! flag_no_function_cse)
200 funexp = force_reg (Pmode, funexp);
201 }
202
203 if (static_chain_value != 0
204 && (TREE_CODE (fndecl_or_type) != FUNCTION_DECL
205 || DECL_STATIC_CHAIN (fndecl_or_type)))
206 {
207 rtx chain;
208
209 chain = targetm.calls.static_chain (fndecl_or_type, false);
210 static_chain_value = convert_memory_address (Pmode, static_chain_value);
211
212 emit_move_insn (chain, static_chain_value);
213 if (REG_P (chain))
214 use_reg (call_fusage, chain);
215 }
216
217 return funexp;
218 }
219
220 /* Generate instructions to call function FUNEXP,
221 and optionally pop the results.
222 The CALL_INSN is the first insn generated.
223
224 FNDECL is the declaration node of the function. This is given to the
225 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
226 its own args.
227
228 FUNTYPE is the data type of the function. This is given to the hook
229 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
230 own args. We used to allow an identifier for library functions, but
231 that doesn't work when the return type is an aggregate type and the
232 calling convention says that the pointer to this aggregate is to be
233 popped by the callee.
234
235 STACK_SIZE is the number of bytes of arguments on the stack,
236 ROUNDED_STACK_SIZE is that number rounded up to
237 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
238 both to put into the call insn and to generate explicit popping
239 code if necessary.
240
241 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
242 It is zero if this call doesn't want a structure value.
243
244 NEXT_ARG_REG is the rtx that results from executing
245 targetm.calls.function_arg (&args_so_far, VOIDmode, void_type_node, true)
246 just after all the args have had their registers assigned.
247 This could be whatever you like, but normally it is the first
248 arg-register beyond those used for args in this call,
249 or 0 if all the arg-registers are used in this call.
250 It is passed on to `gen_call' so you can put this info in the call insn.
251
252 VALREG is a hard register in which a value is returned,
253 or 0 if the call does not return a value.
254
255 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
256 the args to this call were processed.
257 We restore `inhibit_defer_pop' to that value.
258
259 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
260 denote registers used by the called function. */
261
262 static void
263 emit_call_1 (rtx funexp, tree fntree ATTRIBUTE_UNUSED, tree fndecl ATTRIBUTE_UNUSED,
264 tree funtype ATTRIBUTE_UNUSED,
265 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED,
266 HOST_WIDE_INT rounded_stack_size,
267 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED,
268 rtx next_arg_reg ATTRIBUTE_UNUSED, rtx valreg,
269 int old_inhibit_defer_pop, rtx call_fusage, int ecf_flags,
270 cumulative_args_t args_so_far ATTRIBUTE_UNUSED)
271 {
272 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
273 rtx call, funmem, pat;
274 int already_popped = 0;
275 HOST_WIDE_INT n_popped
276 = targetm.calls.return_pops_args (fndecl, funtype, stack_size);
277
278 #ifdef CALL_POPS_ARGS
279 n_popped += CALL_POPS_ARGS (*get_cumulative_args (args_so_far));
280 #endif
281
282 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
283 and we don't want to load it into a register as an optimization,
284 because prepare_call_address already did it if it should be done. */
285 if (GET_CODE (funexp) != SYMBOL_REF)
286 funexp = memory_address (FUNCTION_MODE, funexp);
287
288 funmem = gen_rtx_MEM (FUNCTION_MODE, funexp);
289 if (fndecl && TREE_CODE (fndecl) == FUNCTION_DECL)
290 {
291 tree t = fndecl;
292
293 /* Although a built-in FUNCTION_DECL and its non-__builtin
294 counterpart compare equal and get a shared mem_attrs, they
295 produce different dump output in compare-debug compilations,
296 if an entry gets garbage collected in one compilation, then
297 adds a different (but equivalent) entry, while the other
298 doesn't run the garbage collector at the same spot and then
299 shares the mem_attr with the equivalent entry. */
300 if (DECL_BUILT_IN_CLASS (t) == BUILT_IN_NORMAL)
301 {
302 tree t2 = builtin_decl_explicit (DECL_FUNCTION_CODE (t));
303 if (t2)
304 t = t2;
305 }
306
307 set_mem_expr (funmem, t);
308 }
309 else if (fntree)
310 set_mem_expr (funmem, build_simple_mem_ref (CALL_EXPR_FN (fntree)));
311
312 if (ecf_flags & ECF_SIBCALL)
313 {
314 if (valreg)
315 pat = targetm.gen_sibcall_value (valreg, funmem,
316 rounded_stack_size_rtx,
317 next_arg_reg, NULL_RTX);
318 else
319 pat = targetm.gen_sibcall (funmem, rounded_stack_size_rtx,
320 next_arg_reg, GEN_INT (struct_value_size));
321 }
322 /* If the target has "call" or "call_value" insns, then prefer them
323 if no arguments are actually popped. If the target does not have
324 "call" or "call_value" insns, then we must use the popping versions
325 even if the call has no arguments to pop. */
326 else if (n_popped > 0
327 || !(valreg
328 ? targetm.have_call_value ()
329 : targetm.have_call ()))
330 {
331 rtx n_pop = GEN_INT (n_popped);
332
333 /* If this subroutine pops its own args, record that in the call insn
334 if possible, for the sake of frame pointer elimination. */
335
336 if (valreg)
337 pat = targetm.gen_call_value_pop (valreg, funmem,
338 rounded_stack_size_rtx,
339 next_arg_reg, n_pop);
340 else
341 pat = targetm.gen_call_pop (funmem, rounded_stack_size_rtx,
342 next_arg_reg, n_pop);
343
344 already_popped = 1;
345 }
346 else
347 {
348 if (valreg)
349 pat = targetm.gen_call_value (valreg, funmem, rounded_stack_size_rtx,
350 next_arg_reg, NULL_RTX);
351 else
352 pat = targetm.gen_call (funmem, rounded_stack_size_rtx, next_arg_reg,
353 GEN_INT (struct_value_size));
354 }
355 emit_insn (pat);
356
357 /* Find the call we just emitted. */
358 rtx_call_insn *call_insn = last_call_insn ();
359
360 /* Some target create a fresh MEM instead of reusing the one provided
361 above. Set its MEM_EXPR. */
362 call = get_call_rtx_from (call_insn);
363 if (call
364 && MEM_EXPR (XEXP (call, 0)) == NULL_TREE
365 && MEM_EXPR (funmem) != NULL_TREE)
366 set_mem_expr (XEXP (call, 0), MEM_EXPR (funmem));
367
368 /* Mark instrumented calls. */
369 if (call && fntree)
370 CALL_EXPR_WITH_BOUNDS_P (call) = CALL_WITH_BOUNDS_P (fntree);
371
372 /* Put the register usage information there. */
373 add_function_usage_to (call_insn, call_fusage);
374
375 /* If this is a const call, then set the insn's unchanging bit. */
376 if (ecf_flags & ECF_CONST)
377 RTL_CONST_CALL_P (call_insn) = 1;
378
379 /* If this is a pure call, then set the insn's unchanging bit. */
380 if (ecf_flags & ECF_PURE)
381 RTL_PURE_CALL_P (call_insn) = 1;
382
383 /* If this is a const call, then set the insn's unchanging bit. */
384 if (ecf_flags & ECF_LOOPING_CONST_OR_PURE)
385 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn) = 1;
386
387 /* Create a nothrow REG_EH_REGION note, if needed. */
388 make_reg_eh_region_note (call_insn, ecf_flags, 0);
389
390 if (ecf_flags & ECF_NORETURN)
391 add_reg_note (call_insn, REG_NORETURN, const0_rtx);
392
393 if (ecf_flags & ECF_RETURNS_TWICE)
394 {
395 add_reg_note (call_insn, REG_SETJMP, const0_rtx);
396 cfun->calls_setjmp = 1;
397 }
398
399 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
400
401 /* Restore this now, so that we do defer pops for this call's args
402 if the context of the call as a whole permits. */
403 inhibit_defer_pop = old_inhibit_defer_pop;
404
405 if (n_popped > 0)
406 {
407 if (!already_popped)
408 CALL_INSN_FUNCTION_USAGE (call_insn)
409 = gen_rtx_EXPR_LIST (VOIDmode,
410 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
411 CALL_INSN_FUNCTION_USAGE (call_insn));
412 rounded_stack_size -= n_popped;
413 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
414 stack_pointer_delta -= n_popped;
415
416 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
417
418 /* If popup is needed, stack realign must use DRAP */
419 if (SUPPORTS_STACK_ALIGNMENT)
420 crtl->need_drap = true;
421 }
422 /* For noreturn calls when not accumulating outgoing args force
423 REG_ARGS_SIZE note to prevent crossjumping of calls with different
424 args sizes. */
425 else if (!ACCUMULATE_OUTGOING_ARGS && (ecf_flags & ECF_NORETURN) != 0)
426 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
427
428 if (!ACCUMULATE_OUTGOING_ARGS)
429 {
430 /* If returning from the subroutine does not automatically pop the args,
431 we need an instruction to pop them sooner or later.
432 Perhaps do it now; perhaps just record how much space to pop later.
433
434 If returning from the subroutine does pop the args, indicate that the
435 stack pointer will be changed. */
436
437 if (rounded_stack_size != 0)
438 {
439 if (ecf_flags & ECF_NORETURN)
440 /* Just pretend we did the pop. */
441 stack_pointer_delta -= rounded_stack_size;
442 else if (flag_defer_pop && inhibit_defer_pop == 0
443 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
444 pending_stack_adjust += rounded_stack_size;
445 else
446 adjust_stack (rounded_stack_size_rtx);
447 }
448 }
449 /* When we accumulate outgoing args, we must avoid any stack manipulations.
450 Restore the stack pointer to its original value now. Usually
451 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
452 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
453 popping variants of functions exist as well.
454
455 ??? We may optimize similar to defer_pop above, but it is
456 probably not worthwhile.
457
458 ??? It will be worthwhile to enable combine_stack_adjustments even for
459 such machines. */
460 else if (n_popped)
461 anti_adjust_stack (GEN_INT (n_popped));
462 }
463
464 /* Determine if the function identified by NAME and FNDECL is one with
465 special properties we wish to know about.
466
467 For example, if the function might return more than one time (setjmp), then
468 set RETURNS_TWICE to a nonzero value.
469
470 Similarly set NORETURN if the function is in the longjmp family.
471
472 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
473 space from the stack such as alloca. */
474
475 static int
476 special_function_p (const_tree fndecl, int flags)
477 {
478 tree name_decl = DECL_NAME (fndecl);
479
480 /* For instrumentation clones we want to derive flags
481 from the original name. */
482 if (cgraph_node::get (fndecl)
483 && cgraph_node::get (fndecl)->instrumentation_clone)
484 name_decl = DECL_NAME (cgraph_node::get (fndecl)->orig_decl);
485
486 if (fndecl && name_decl
487 && IDENTIFIER_LENGTH (name_decl) <= 17
488 /* Exclude functions not at the file scope, or not `extern',
489 since they are not the magic functions we would otherwise
490 think they are.
491 FIXME: this should be handled with attributes, not with this
492 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
493 because you can declare fork() inside a function if you
494 wish. */
495 && (DECL_CONTEXT (fndecl) == NULL_TREE
496 || TREE_CODE (DECL_CONTEXT (fndecl)) == TRANSLATION_UNIT_DECL)
497 && TREE_PUBLIC (fndecl))
498 {
499 const char *name = IDENTIFIER_POINTER (name_decl);
500 const char *tname = name;
501
502 /* We assume that alloca will always be called by name. It
503 makes no sense to pass it as a pointer-to-function to
504 anything that does not understand its behavior. */
505 if (IDENTIFIER_LENGTH (name_decl) == 6
506 && name[0] == 'a'
507 && ! strcmp (name, "alloca"))
508 flags |= ECF_MAY_BE_ALLOCA;
509
510 /* Disregard prefix _, __, __x or __builtin_. */
511 if (name[0] == '_')
512 {
513 if (name[1] == '_'
514 && name[2] == 'b'
515 && !strncmp (name + 3, "uiltin_", 7))
516 tname += 10;
517 else if (name[1] == '_' && name[2] == 'x')
518 tname += 3;
519 else if (name[1] == '_')
520 tname += 2;
521 else
522 tname += 1;
523 }
524
525 if (tname[0] == 's')
526 {
527 if ((tname[1] == 'e'
528 && (! strcmp (tname, "setjmp")
529 || ! strcmp (tname, "setjmp_syscall")))
530 || (tname[1] == 'i'
531 && ! strcmp (tname, "sigsetjmp"))
532 || (tname[1] == 'a'
533 && ! strcmp (tname, "savectx")))
534 flags |= ECF_RETURNS_TWICE | ECF_LEAF;
535
536 if (tname[1] == 'i'
537 && ! strcmp (tname, "siglongjmp"))
538 flags |= ECF_NORETURN;
539 }
540 else if ((tname[0] == 'q' && tname[1] == 's'
541 && ! strcmp (tname, "qsetjmp"))
542 || (tname[0] == 'v' && tname[1] == 'f'
543 && ! strcmp (tname, "vfork"))
544 || (tname[0] == 'g' && tname[1] == 'e'
545 && !strcmp (tname, "getcontext")))
546 flags |= ECF_RETURNS_TWICE | ECF_LEAF;
547
548 else if (tname[0] == 'l' && tname[1] == 'o'
549 && ! strcmp (tname, "longjmp"))
550 flags |= ECF_NORETURN;
551 }
552
553 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
554 switch (DECL_FUNCTION_CODE (fndecl))
555 {
556 case BUILT_IN_ALLOCA:
557 case BUILT_IN_ALLOCA_WITH_ALIGN:
558 flags |= ECF_MAY_BE_ALLOCA;
559 break;
560 default:
561 break;
562 }
563
564 return flags;
565 }
566
567 /* Similar to special_function_p; return a set of ERF_ flags for the
568 function FNDECL. */
569 static int
570 decl_return_flags (tree fndecl)
571 {
572 tree attr;
573 tree type = TREE_TYPE (fndecl);
574 if (!type)
575 return 0;
576
577 attr = lookup_attribute ("fn spec", TYPE_ATTRIBUTES (type));
578 if (!attr)
579 return 0;
580
581 attr = TREE_VALUE (TREE_VALUE (attr));
582 if (!attr || TREE_STRING_LENGTH (attr) < 1)
583 return 0;
584
585 switch (TREE_STRING_POINTER (attr)[0])
586 {
587 case '1':
588 case '2':
589 case '3':
590 case '4':
591 return ERF_RETURNS_ARG | (TREE_STRING_POINTER (attr)[0] - '1');
592
593 case 'm':
594 return ERF_NOALIAS;
595
596 case '.':
597 default:
598 return 0;
599 }
600 }
601
602 /* Return nonzero when FNDECL represents a call to setjmp. */
603
604 int
605 setjmp_call_p (const_tree fndecl)
606 {
607 if (DECL_IS_RETURNS_TWICE (fndecl))
608 return ECF_RETURNS_TWICE;
609 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
610 }
611
612
613 /* Return true if STMT is an alloca call. */
614
615 bool
616 gimple_alloca_call_p (const gimple *stmt)
617 {
618 tree fndecl;
619
620 if (!is_gimple_call (stmt))
621 return false;
622
623 fndecl = gimple_call_fndecl (stmt);
624 if (fndecl && (special_function_p (fndecl, 0) & ECF_MAY_BE_ALLOCA))
625 return true;
626
627 return false;
628 }
629
630 /* Return true when exp contains alloca call. */
631
632 bool
633 alloca_call_p (const_tree exp)
634 {
635 tree fndecl;
636 if (TREE_CODE (exp) == CALL_EXPR
637 && (fndecl = get_callee_fndecl (exp))
638 && (special_function_p (fndecl, 0) & ECF_MAY_BE_ALLOCA))
639 return true;
640 return false;
641 }
642
643 /* Return TRUE if FNDECL is either a TM builtin or a TM cloned
644 function. Return FALSE otherwise. */
645
646 static bool
647 is_tm_builtin (const_tree fndecl)
648 {
649 if (fndecl == NULL)
650 return false;
651
652 if (decl_is_tm_clone (fndecl))
653 return true;
654
655 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
656 {
657 switch (DECL_FUNCTION_CODE (fndecl))
658 {
659 case BUILT_IN_TM_COMMIT:
660 case BUILT_IN_TM_COMMIT_EH:
661 case BUILT_IN_TM_ABORT:
662 case BUILT_IN_TM_IRREVOCABLE:
663 case BUILT_IN_TM_GETTMCLONE_IRR:
664 case BUILT_IN_TM_MEMCPY:
665 case BUILT_IN_TM_MEMMOVE:
666 case BUILT_IN_TM_MEMSET:
667 CASE_BUILT_IN_TM_STORE (1):
668 CASE_BUILT_IN_TM_STORE (2):
669 CASE_BUILT_IN_TM_STORE (4):
670 CASE_BUILT_IN_TM_STORE (8):
671 CASE_BUILT_IN_TM_STORE (FLOAT):
672 CASE_BUILT_IN_TM_STORE (DOUBLE):
673 CASE_BUILT_IN_TM_STORE (LDOUBLE):
674 CASE_BUILT_IN_TM_STORE (M64):
675 CASE_BUILT_IN_TM_STORE (M128):
676 CASE_BUILT_IN_TM_STORE (M256):
677 CASE_BUILT_IN_TM_LOAD (1):
678 CASE_BUILT_IN_TM_LOAD (2):
679 CASE_BUILT_IN_TM_LOAD (4):
680 CASE_BUILT_IN_TM_LOAD (8):
681 CASE_BUILT_IN_TM_LOAD (FLOAT):
682 CASE_BUILT_IN_TM_LOAD (DOUBLE):
683 CASE_BUILT_IN_TM_LOAD (LDOUBLE):
684 CASE_BUILT_IN_TM_LOAD (M64):
685 CASE_BUILT_IN_TM_LOAD (M128):
686 CASE_BUILT_IN_TM_LOAD (M256):
687 case BUILT_IN_TM_LOG:
688 case BUILT_IN_TM_LOG_1:
689 case BUILT_IN_TM_LOG_2:
690 case BUILT_IN_TM_LOG_4:
691 case BUILT_IN_TM_LOG_8:
692 case BUILT_IN_TM_LOG_FLOAT:
693 case BUILT_IN_TM_LOG_DOUBLE:
694 case BUILT_IN_TM_LOG_LDOUBLE:
695 case BUILT_IN_TM_LOG_M64:
696 case BUILT_IN_TM_LOG_M128:
697 case BUILT_IN_TM_LOG_M256:
698 return true;
699 default:
700 break;
701 }
702 }
703 return false;
704 }
705
706 /* Detect flags (function attributes) from the function decl or type node. */
707
708 int
709 flags_from_decl_or_type (const_tree exp)
710 {
711 int flags = 0;
712
713 if (DECL_P (exp))
714 {
715 /* The function exp may have the `malloc' attribute. */
716 if (DECL_IS_MALLOC (exp))
717 flags |= ECF_MALLOC;
718
719 /* The function exp may have the `returns_twice' attribute. */
720 if (DECL_IS_RETURNS_TWICE (exp))
721 flags |= ECF_RETURNS_TWICE;
722
723 /* Process the pure and const attributes. */
724 if (TREE_READONLY (exp))
725 flags |= ECF_CONST;
726 if (DECL_PURE_P (exp))
727 flags |= ECF_PURE;
728 if (DECL_LOOPING_CONST_OR_PURE_P (exp))
729 flags |= ECF_LOOPING_CONST_OR_PURE;
730
731 if (DECL_IS_NOVOPS (exp))
732 flags |= ECF_NOVOPS;
733 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp)))
734 flags |= ECF_LEAF;
735
736 if (TREE_NOTHROW (exp))
737 flags |= ECF_NOTHROW;
738
739 if (flag_tm)
740 {
741 if (is_tm_builtin (exp))
742 flags |= ECF_TM_BUILTIN;
743 else if ((flags & (ECF_CONST|ECF_NOVOPS)) != 0
744 || lookup_attribute ("transaction_pure",
745 TYPE_ATTRIBUTES (TREE_TYPE (exp))))
746 flags |= ECF_TM_PURE;
747 }
748
749 flags = special_function_p (exp, flags);
750 }
751 else if (TYPE_P (exp))
752 {
753 if (TYPE_READONLY (exp))
754 flags |= ECF_CONST;
755
756 if (flag_tm
757 && ((flags & ECF_CONST) != 0
758 || lookup_attribute ("transaction_pure", TYPE_ATTRIBUTES (exp))))
759 flags |= ECF_TM_PURE;
760 }
761 else
762 gcc_unreachable ();
763
764 if (TREE_THIS_VOLATILE (exp))
765 {
766 flags |= ECF_NORETURN;
767 if (flags & (ECF_CONST|ECF_PURE))
768 flags |= ECF_LOOPING_CONST_OR_PURE;
769 }
770
771 return flags;
772 }
773
774 /* Detect flags from a CALL_EXPR. */
775
776 int
777 call_expr_flags (const_tree t)
778 {
779 int flags;
780 tree decl = get_callee_fndecl (t);
781
782 if (decl)
783 flags = flags_from_decl_or_type (decl);
784 else if (CALL_EXPR_FN (t) == NULL_TREE)
785 flags = internal_fn_flags (CALL_EXPR_IFN (t));
786 else
787 {
788 t = TREE_TYPE (CALL_EXPR_FN (t));
789 if (t && TREE_CODE (t) == POINTER_TYPE)
790 flags = flags_from_decl_or_type (TREE_TYPE (t));
791 else
792 flags = 0;
793 }
794
795 return flags;
796 }
797
798 /* Return true if TYPE should be passed by invisible reference. */
799
800 bool
801 pass_by_reference (CUMULATIVE_ARGS *ca, machine_mode mode,
802 tree type, bool named_arg)
803 {
804 if (type)
805 {
806 /* If this type contains non-trivial constructors, then it is
807 forbidden for the middle-end to create any new copies. */
808 if (TREE_ADDRESSABLE (type))
809 return true;
810
811 /* GCC post 3.4 passes *all* variable sized types by reference. */
812 if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
813 return true;
814
815 /* If a record type should be passed the same as its first (and only)
816 member, use the type and mode of that member. */
817 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
818 {
819 type = TREE_TYPE (first_field (type));
820 mode = TYPE_MODE (type);
821 }
822 }
823
824 return targetm.calls.pass_by_reference (pack_cumulative_args (ca), mode,
825 type, named_arg);
826 }
827
828 /* Return true if TYPE, which is passed by reference, should be callee
829 copied instead of caller copied. */
830
831 bool
832 reference_callee_copied (CUMULATIVE_ARGS *ca, machine_mode mode,
833 tree type, bool named_arg)
834 {
835 if (type && TREE_ADDRESSABLE (type))
836 return false;
837 return targetm.calls.callee_copies (pack_cumulative_args (ca), mode, type,
838 named_arg);
839 }
840
841
842 /* Precompute all register parameters as described by ARGS, storing values
843 into fields within the ARGS array.
844
845 NUM_ACTUALS indicates the total number elements in the ARGS array.
846
847 Set REG_PARM_SEEN if we encounter a register parameter. */
848
849 static void
850 precompute_register_parameters (int num_actuals, struct arg_data *args,
851 int *reg_parm_seen)
852 {
853 int i;
854
855 *reg_parm_seen = 0;
856
857 for (i = 0; i < num_actuals; i++)
858 if (args[i].reg != 0 && ! args[i].pass_on_stack)
859 {
860 *reg_parm_seen = 1;
861
862 if (args[i].value == 0)
863 {
864 push_temp_slots ();
865 args[i].value = expand_normal (args[i].tree_value);
866 preserve_temp_slots (args[i].value);
867 pop_temp_slots ();
868 }
869
870 /* If we are to promote the function arg to a wider mode,
871 do it now. */
872
873 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
874 args[i].value
875 = convert_modes (args[i].mode,
876 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
877 args[i].value, args[i].unsignedp);
878
879 /* If the value is a non-legitimate constant, force it into a
880 pseudo now. TLS symbols sometimes need a call to resolve. */
881 if (CONSTANT_P (args[i].value)
882 && !targetm.legitimate_constant_p (args[i].mode, args[i].value))
883 args[i].value = force_reg (args[i].mode, args[i].value);
884
885 /* If we're going to have to load the value by parts, pull the
886 parts into pseudos. The part extraction process can involve
887 non-trivial computation. */
888 if (GET_CODE (args[i].reg) == PARALLEL)
889 {
890 tree type = TREE_TYPE (args[i].tree_value);
891 args[i].parallel_value
892 = emit_group_load_into_temps (args[i].reg, args[i].value,
893 type, int_size_in_bytes (type));
894 }
895
896 /* If the value is expensive, and we are inside an appropriately
897 short loop, put the value into a pseudo and then put the pseudo
898 into the hard reg.
899
900 For small register classes, also do this if this call uses
901 register parameters. This is to avoid reload conflicts while
902 loading the parameters registers. */
903
904 else if ((! (REG_P (args[i].value)
905 || (GET_CODE (args[i].value) == SUBREG
906 && REG_P (SUBREG_REG (args[i].value)))))
907 && args[i].mode != BLKmode
908 && (set_src_cost (args[i].value, args[i].mode,
909 optimize_insn_for_speed_p ())
910 > COSTS_N_INSNS (1))
911 && ((*reg_parm_seen
912 && targetm.small_register_classes_for_mode_p (args[i].mode))
913 || optimize))
914 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
915 }
916 }
917
918 #ifdef REG_PARM_STACK_SPACE
919
920 /* The argument list is the property of the called routine and it
921 may clobber it. If the fixed area has been used for previous
922 parameters, we must save and restore it. */
923
924 static rtx
925 save_fixed_argument_area (int reg_parm_stack_space, rtx argblock, int *low_to_save, int *high_to_save)
926 {
927 int low;
928 int high;
929
930 /* Compute the boundary of the area that needs to be saved, if any. */
931 high = reg_parm_stack_space;
932 if (ARGS_GROW_DOWNWARD)
933 high += 1;
934
935 if (high > highest_outgoing_arg_in_use)
936 high = highest_outgoing_arg_in_use;
937
938 for (low = 0; low < high; low++)
939 if (stack_usage_map[low] != 0)
940 {
941 int num_to_save;
942 machine_mode save_mode;
943 int delta;
944 rtx addr;
945 rtx stack_area;
946 rtx save_area;
947
948 while (stack_usage_map[--high] == 0)
949 ;
950
951 *low_to_save = low;
952 *high_to_save = high;
953
954 num_to_save = high - low + 1;
955 save_mode = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
956
957 /* If we don't have the required alignment, must do this
958 in BLKmode. */
959 if ((low & (MIN (GET_MODE_SIZE (save_mode),
960 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
961 save_mode = BLKmode;
962
963 if (ARGS_GROW_DOWNWARD)
964 delta = -high;
965 else
966 delta = low;
967
968 addr = plus_constant (Pmode, argblock, delta);
969 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
970
971 set_mem_align (stack_area, PARM_BOUNDARY);
972 if (save_mode == BLKmode)
973 {
974 save_area = assign_stack_temp (BLKmode, num_to_save);
975 emit_block_move (validize_mem (save_area), stack_area,
976 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
977 }
978 else
979 {
980 save_area = gen_reg_rtx (save_mode);
981 emit_move_insn (save_area, stack_area);
982 }
983
984 return save_area;
985 }
986
987 return NULL_RTX;
988 }
989
990 static void
991 restore_fixed_argument_area (rtx save_area, rtx argblock, int high_to_save, int low_to_save)
992 {
993 machine_mode save_mode = GET_MODE (save_area);
994 int delta;
995 rtx addr, stack_area;
996
997 if (ARGS_GROW_DOWNWARD)
998 delta = -high_to_save;
999 else
1000 delta = low_to_save;
1001
1002 addr = plus_constant (Pmode, argblock, delta);
1003 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
1004 set_mem_align (stack_area, PARM_BOUNDARY);
1005
1006 if (save_mode != BLKmode)
1007 emit_move_insn (stack_area, save_area);
1008 else
1009 emit_block_move (stack_area, validize_mem (save_area),
1010 GEN_INT (high_to_save - low_to_save + 1),
1011 BLOCK_OP_CALL_PARM);
1012 }
1013 #endif /* REG_PARM_STACK_SPACE */
1014
1015 /* If any elements in ARGS refer to parameters that are to be passed in
1016 registers, but not in memory, and whose alignment does not permit a
1017 direct copy into registers. Copy the values into a group of pseudos
1018 which we will later copy into the appropriate hard registers.
1019
1020 Pseudos for each unaligned argument will be stored into the array
1021 args[argnum].aligned_regs. The caller is responsible for deallocating
1022 the aligned_regs array if it is nonzero. */
1023
1024 static void
1025 store_unaligned_arguments_into_pseudos (struct arg_data *args, int num_actuals)
1026 {
1027 int i, j;
1028
1029 for (i = 0; i < num_actuals; i++)
1030 if (args[i].reg != 0 && ! args[i].pass_on_stack
1031 && GET_CODE (args[i].reg) != PARALLEL
1032 && args[i].mode == BLKmode
1033 && MEM_P (args[i].value)
1034 && (MEM_ALIGN (args[i].value)
1035 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1036 {
1037 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1038 int endian_correction = 0;
1039
1040 if (args[i].partial)
1041 {
1042 gcc_assert (args[i].partial % UNITS_PER_WORD == 0);
1043 args[i].n_aligned_regs = args[i].partial / UNITS_PER_WORD;
1044 }
1045 else
1046 {
1047 args[i].n_aligned_regs
1048 = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
1049 }
1050
1051 args[i].aligned_regs = XNEWVEC (rtx, args[i].n_aligned_regs);
1052
1053 /* Structures smaller than a word are normally aligned to the
1054 least significant byte. On a BYTES_BIG_ENDIAN machine,
1055 this means we must skip the empty high order bytes when
1056 calculating the bit offset. */
1057 if (bytes < UNITS_PER_WORD
1058 #ifdef BLOCK_REG_PADDING
1059 && (BLOCK_REG_PADDING (args[i].mode,
1060 TREE_TYPE (args[i].tree_value), 1)
1061 == downward)
1062 #else
1063 && BYTES_BIG_ENDIAN
1064 #endif
1065 )
1066 endian_correction = BITS_PER_WORD - bytes * BITS_PER_UNIT;
1067
1068 for (j = 0; j < args[i].n_aligned_regs; j++)
1069 {
1070 rtx reg = gen_reg_rtx (word_mode);
1071 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1072 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1073
1074 args[i].aligned_regs[j] = reg;
1075 word = extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1076 word_mode, word_mode, false);
1077
1078 /* There is no need to restrict this code to loading items
1079 in TYPE_ALIGN sized hunks. The bitfield instructions can
1080 load up entire word sized registers efficiently.
1081
1082 ??? This may not be needed anymore.
1083 We use to emit a clobber here but that doesn't let later
1084 passes optimize the instructions we emit. By storing 0 into
1085 the register later passes know the first AND to zero out the
1086 bitfield being set in the register is unnecessary. The store
1087 of 0 will be deleted as will at least the first AND. */
1088
1089 emit_move_insn (reg, const0_rtx);
1090
1091 bytes -= bitsize / BITS_PER_UNIT;
1092 store_bit_field (reg, bitsize, endian_correction, 0, 0,
1093 word_mode, word, false);
1094 }
1095 }
1096 }
1097
1098 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1099 CALL_EXPR EXP.
1100
1101 NUM_ACTUALS is the total number of parameters.
1102
1103 N_NAMED_ARGS is the total number of named arguments.
1104
1105 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
1106 value, or null.
1107
1108 FNDECL is the tree code for the target of this call (if known)
1109
1110 ARGS_SO_FAR holds state needed by the target to know where to place
1111 the next argument.
1112
1113 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1114 for arguments which are passed in registers.
1115
1116 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1117 and may be modified by this routine.
1118
1119 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1120 flags which may be modified by this routine.
1121
1122 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
1123 that requires allocation of stack space.
1124
1125 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1126 the thunked-to function. */
1127
1128 static void
1129 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
1130 struct arg_data *args,
1131 struct args_size *args_size,
1132 int n_named_args ATTRIBUTE_UNUSED,
1133 tree exp, tree struct_value_addr_value,
1134 tree fndecl, tree fntype,
1135 cumulative_args_t args_so_far,
1136 int reg_parm_stack_space,
1137 rtx *old_stack_level, int *old_pending_adj,
1138 int *must_preallocate, int *ecf_flags,
1139 bool *may_tailcall, bool call_from_thunk_p)
1140 {
1141 CUMULATIVE_ARGS *args_so_far_pnt = get_cumulative_args (args_so_far);
1142 location_t loc = EXPR_LOCATION (exp);
1143
1144 /* Count arg position in order args appear. */
1145 int argpos;
1146
1147 int i;
1148
1149 args_size->constant = 0;
1150 args_size->var = 0;
1151
1152 bitmap_obstack_initialize (NULL);
1153
1154 /* In this loop, we consider args in the order they are written.
1155 We fill up ARGS from the back. */
1156
1157 i = num_actuals - 1;
1158 {
1159 int j = i, ptr_arg = -1;
1160 call_expr_arg_iterator iter;
1161 tree arg;
1162 bitmap slots = NULL;
1163
1164 if (struct_value_addr_value)
1165 {
1166 args[j].tree_value = struct_value_addr_value;
1167 j--;
1168
1169 /* If we pass structure address then we need to
1170 create bounds for it. Since created bounds is
1171 a call statement, we expand it right here to avoid
1172 fixing all other places where it may be expanded. */
1173 if (CALL_WITH_BOUNDS_P (exp))
1174 {
1175 args[j].value = gen_reg_rtx (targetm.chkp_bound_mode ());
1176 args[j].tree_value
1177 = chkp_make_bounds_for_struct_addr (struct_value_addr_value);
1178 expand_expr_real (args[j].tree_value, args[j].value, VOIDmode,
1179 EXPAND_NORMAL, 0, false);
1180 args[j].pointer_arg = j + 1;
1181 j--;
1182 }
1183 }
1184 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
1185 {
1186 tree argtype = TREE_TYPE (arg);
1187
1188 /* Remember last param with pointer and associate it
1189 with following pointer bounds. */
1190 if (CALL_WITH_BOUNDS_P (exp)
1191 && chkp_type_has_pointer (argtype))
1192 {
1193 if (slots)
1194 BITMAP_FREE (slots);
1195 ptr_arg = j;
1196 if (!BOUNDED_TYPE_P (argtype))
1197 {
1198 slots = BITMAP_ALLOC (NULL);
1199 chkp_find_bound_slots (argtype, slots);
1200 }
1201 }
1202 else if (POINTER_BOUNDS_TYPE_P (argtype))
1203 {
1204 /* We expect bounds in instrumented calls only.
1205 Otherwise it is a sign we lost flag due to some optimization
1206 and may emit call args incorrectly. */
1207 gcc_assert (CALL_WITH_BOUNDS_P (exp));
1208
1209 /* For structures look for the next available pointer. */
1210 if (ptr_arg != -1 && slots)
1211 {
1212 unsigned bnd_no = bitmap_first_set_bit (slots);
1213 args[j].pointer_offset =
1214 bnd_no * POINTER_SIZE / BITS_PER_UNIT;
1215
1216 bitmap_clear_bit (slots, bnd_no);
1217
1218 /* Check we have no more pointers in the structure. */
1219 if (bitmap_empty_p (slots))
1220 BITMAP_FREE (slots);
1221 }
1222 args[j].pointer_arg = ptr_arg;
1223
1224 /* Check we covered all pointers in the previous
1225 non bounds arg. */
1226 if (!slots)
1227 ptr_arg = -1;
1228 }
1229 else
1230 ptr_arg = -1;
1231
1232 if (targetm.calls.split_complex_arg
1233 && argtype
1234 && TREE_CODE (argtype) == COMPLEX_TYPE
1235 && targetm.calls.split_complex_arg (argtype))
1236 {
1237 tree subtype = TREE_TYPE (argtype);
1238 args[j].tree_value = build1 (REALPART_EXPR, subtype, arg);
1239 j--;
1240 args[j].tree_value = build1 (IMAGPART_EXPR, subtype, arg);
1241 }
1242 else
1243 args[j].tree_value = arg;
1244 j--;
1245 }
1246
1247 if (slots)
1248 BITMAP_FREE (slots);
1249 }
1250
1251 bitmap_obstack_release (NULL);
1252
1253 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1254 for (argpos = 0; argpos < num_actuals; i--, argpos++)
1255 {
1256 tree type = TREE_TYPE (args[i].tree_value);
1257 int unsignedp;
1258 machine_mode mode;
1259
1260 /* Replace erroneous argument with constant zero. */
1261 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1262 args[i].tree_value = integer_zero_node, type = integer_type_node;
1263
1264 /* If TYPE is a transparent union or record, pass things the way
1265 we would pass the first field of the union or record. We have
1266 already verified that the modes are the same. */
1267 if ((TREE_CODE (type) == UNION_TYPE || TREE_CODE (type) == RECORD_TYPE)
1268 && TYPE_TRANSPARENT_AGGR (type))
1269 type = TREE_TYPE (first_field (type));
1270
1271 /* Decide where to pass this arg.
1272
1273 args[i].reg is nonzero if all or part is passed in registers.
1274
1275 args[i].partial is nonzero if part but not all is passed in registers,
1276 and the exact value says how many bytes are passed in registers.
1277
1278 args[i].pass_on_stack is nonzero if the argument must at least be
1279 computed on the stack. It may then be loaded back into registers
1280 if args[i].reg is nonzero.
1281
1282 These decisions are driven by the FUNCTION_... macros and must agree
1283 with those made by function.c. */
1284
1285 /* See if this argument should be passed by invisible reference. */
1286 if (pass_by_reference (args_so_far_pnt, TYPE_MODE (type),
1287 type, argpos < n_named_args))
1288 {
1289 bool callee_copies;
1290 tree base = NULL_TREE;
1291
1292 callee_copies
1293 = reference_callee_copied (args_so_far_pnt, TYPE_MODE (type),
1294 type, argpos < n_named_args);
1295
1296 /* If we're compiling a thunk, pass through invisible references
1297 instead of making a copy. */
1298 if (call_from_thunk_p
1299 || (callee_copies
1300 && !TREE_ADDRESSABLE (type)
1301 && (base = get_base_address (args[i].tree_value))
1302 && TREE_CODE (base) != SSA_NAME
1303 && (!DECL_P (base) || MEM_P (DECL_RTL (base)))))
1304 {
1305 /* We may have turned the parameter value into an SSA name.
1306 Go back to the original parameter so we can take the
1307 address. */
1308 if (TREE_CODE (args[i].tree_value) == SSA_NAME)
1309 {
1310 gcc_assert (SSA_NAME_IS_DEFAULT_DEF (args[i].tree_value));
1311 args[i].tree_value = SSA_NAME_VAR (args[i].tree_value);
1312 gcc_assert (TREE_CODE (args[i].tree_value) == PARM_DECL);
1313 }
1314 /* Argument setup code may have copied the value to register. We
1315 revert that optimization now because the tail call code must
1316 use the original location. */
1317 if (TREE_CODE (args[i].tree_value) == PARM_DECL
1318 && !MEM_P (DECL_RTL (args[i].tree_value))
1319 && DECL_INCOMING_RTL (args[i].tree_value)
1320 && MEM_P (DECL_INCOMING_RTL (args[i].tree_value)))
1321 set_decl_rtl (args[i].tree_value,
1322 DECL_INCOMING_RTL (args[i].tree_value));
1323
1324 mark_addressable (args[i].tree_value);
1325
1326 /* We can't use sibcalls if a callee-copied argument is
1327 stored in the current function's frame. */
1328 if (!call_from_thunk_p && DECL_P (base) && !TREE_STATIC (base))
1329 *may_tailcall = false;
1330
1331 args[i].tree_value = build_fold_addr_expr_loc (loc,
1332 args[i].tree_value);
1333 type = TREE_TYPE (args[i].tree_value);
1334
1335 if (*ecf_flags & ECF_CONST)
1336 *ecf_flags &= ~(ECF_CONST | ECF_LOOPING_CONST_OR_PURE);
1337 }
1338 else
1339 {
1340 /* We make a copy of the object and pass the address to the
1341 function being called. */
1342 rtx copy;
1343
1344 if (!COMPLETE_TYPE_P (type)
1345 || TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST
1346 || (flag_stack_check == GENERIC_STACK_CHECK
1347 && compare_tree_int (TYPE_SIZE_UNIT (type),
1348 STACK_CHECK_MAX_VAR_SIZE) > 0))
1349 {
1350 /* This is a variable-sized object. Make space on the stack
1351 for it. */
1352 rtx size_rtx = expr_size (args[i].tree_value);
1353
1354 if (*old_stack_level == 0)
1355 {
1356 emit_stack_save (SAVE_BLOCK, old_stack_level);
1357 *old_pending_adj = pending_stack_adjust;
1358 pending_stack_adjust = 0;
1359 }
1360
1361 /* We can pass TRUE as the 4th argument because we just
1362 saved the stack pointer and will restore it right after
1363 the call. */
1364 copy = allocate_dynamic_stack_space (size_rtx,
1365 TYPE_ALIGN (type),
1366 TYPE_ALIGN (type),
1367 true);
1368 copy = gen_rtx_MEM (BLKmode, copy);
1369 set_mem_attributes (copy, type, 1);
1370 }
1371 else
1372 copy = assign_temp (type, 1, 0);
1373
1374 store_expr (args[i].tree_value, copy, 0, false, false);
1375
1376 /* Just change the const function to pure and then let
1377 the next test clear the pure based on
1378 callee_copies. */
1379 if (*ecf_flags & ECF_CONST)
1380 {
1381 *ecf_flags &= ~ECF_CONST;
1382 *ecf_flags |= ECF_PURE;
1383 }
1384
1385 if (!callee_copies && *ecf_flags & ECF_PURE)
1386 *ecf_flags &= ~(ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
1387
1388 args[i].tree_value
1389 = build_fold_addr_expr_loc (loc, make_tree (type, copy));
1390 type = TREE_TYPE (args[i].tree_value);
1391 *may_tailcall = false;
1392 }
1393 }
1394
1395 unsignedp = TYPE_UNSIGNED (type);
1396 mode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
1397 fndecl ? TREE_TYPE (fndecl) : fntype, 0);
1398
1399 args[i].unsignedp = unsignedp;
1400 args[i].mode = mode;
1401
1402 args[i].reg = targetm.calls.function_arg (args_so_far, mode, type,
1403 argpos < n_named_args);
1404
1405 if (args[i].reg && CONST_INT_P (args[i].reg))
1406 {
1407 args[i].special_slot = args[i].reg;
1408 args[i].reg = NULL;
1409 }
1410
1411 /* If this is a sibling call and the machine has register windows, the
1412 register window has to be unwinded before calling the routine, so
1413 arguments have to go into the incoming registers. */
1414 if (targetm.calls.function_incoming_arg != targetm.calls.function_arg)
1415 args[i].tail_call_reg
1416 = targetm.calls.function_incoming_arg (args_so_far, mode, type,
1417 argpos < n_named_args);
1418 else
1419 args[i].tail_call_reg = args[i].reg;
1420
1421 if (args[i].reg)
1422 args[i].partial
1423 = targetm.calls.arg_partial_bytes (args_so_far, mode, type,
1424 argpos < n_named_args);
1425
1426 args[i].pass_on_stack = targetm.calls.must_pass_in_stack (mode, type);
1427
1428 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1429 it means that we are to pass this arg in the register(s) designated
1430 by the PARALLEL, but also to pass it in the stack. */
1431 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1432 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1433 args[i].pass_on_stack = 1;
1434
1435 /* If this is an addressable type, we must preallocate the stack
1436 since we must evaluate the object into its final location.
1437
1438 If this is to be passed in both registers and the stack, it is simpler
1439 to preallocate. */
1440 if (TREE_ADDRESSABLE (type)
1441 || (args[i].pass_on_stack && args[i].reg != 0))
1442 *must_preallocate = 1;
1443
1444 /* No stack allocation and padding for bounds. */
1445 if (POINTER_BOUNDS_P (args[i].tree_value))
1446 ;
1447 /* Compute the stack-size of this argument. */
1448 else if (args[i].reg == 0 || args[i].partial != 0
1449 || reg_parm_stack_space > 0
1450 || args[i].pass_on_stack)
1451 locate_and_pad_parm (mode, type,
1452 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1453 1,
1454 #else
1455 args[i].reg != 0,
1456 #endif
1457 reg_parm_stack_space,
1458 args[i].pass_on_stack ? 0 : args[i].partial,
1459 fndecl, args_size, &args[i].locate);
1460 #ifdef BLOCK_REG_PADDING
1461 else
1462 /* The argument is passed entirely in registers. See at which
1463 end it should be padded. */
1464 args[i].locate.where_pad =
1465 BLOCK_REG_PADDING (mode, type,
1466 int_size_in_bytes (type) <= UNITS_PER_WORD);
1467 #endif
1468
1469 /* Update ARGS_SIZE, the total stack space for args so far. */
1470
1471 args_size->constant += args[i].locate.size.constant;
1472 if (args[i].locate.size.var)
1473 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
1474
1475 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1476 have been used, etc. */
1477
1478 targetm.calls.function_arg_advance (args_so_far, TYPE_MODE (type),
1479 type, argpos < n_named_args);
1480 }
1481 }
1482
1483 /* Update ARGS_SIZE to contain the total size for the argument block.
1484 Return the original constant component of the argument block's size.
1485
1486 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1487 for arguments passed in registers. */
1488
1489 static int
1490 compute_argument_block_size (int reg_parm_stack_space,
1491 struct args_size *args_size,
1492 tree fndecl ATTRIBUTE_UNUSED,
1493 tree fntype ATTRIBUTE_UNUSED,
1494 int preferred_stack_boundary ATTRIBUTE_UNUSED)
1495 {
1496 int unadjusted_args_size = args_size->constant;
1497
1498 /* For accumulate outgoing args mode we don't need to align, since the frame
1499 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1500 backends from generating misaligned frame sizes. */
1501 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1502 preferred_stack_boundary = STACK_BOUNDARY;
1503
1504 /* Compute the actual size of the argument block required. The variable
1505 and constant sizes must be combined, the size may have to be rounded,
1506 and there may be a minimum required size. */
1507
1508 if (args_size->var)
1509 {
1510 args_size->var = ARGS_SIZE_TREE (*args_size);
1511 args_size->constant = 0;
1512
1513 preferred_stack_boundary /= BITS_PER_UNIT;
1514 if (preferred_stack_boundary > 1)
1515 {
1516 /* We don't handle this case yet. To handle it correctly we have
1517 to add the delta, round and subtract the delta.
1518 Currently no machine description requires this support. */
1519 gcc_assert (!(stack_pointer_delta & (preferred_stack_boundary - 1)));
1520 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1521 }
1522
1523 if (reg_parm_stack_space > 0)
1524 {
1525 args_size->var
1526 = size_binop (MAX_EXPR, args_size->var,
1527 ssize_int (reg_parm_stack_space));
1528
1529 /* The area corresponding to register parameters is not to count in
1530 the size of the block we need. So make the adjustment. */
1531 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
1532 args_size->var
1533 = size_binop (MINUS_EXPR, args_size->var,
1534 ssize_int (reg_parm_stack_space));
1535 }
1536 }
1537 else
1538 {
1539 preferred_stack_boundary /= BITS_PER_UNIT;
1540 if (preferred_stack_boundary < 1)
1541 preferred_stack_boundary = 1;
1542 args_size->constant = (((args_size->constant
1543 + stack_pointer_delta
1544 + preferred_stack_boundary - 1)
1545 / preferred_stack_boundary
1546 * preferred_stack_boundary)
1547 - stack_pointer_delta);
1548
1549 args_size->constant = MAX (args_size->constant,
1550 reg_parm_stack_space);
1551
1552 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
1553 args_size->constant -= reg_parm_stack_space;
1554 }
1555 return unadjusted_args_size;
1556 }
1557
1558 /* Precompute parameters as needed for a function call.
1559
1560 FLAGS is mask of ECF_* constants.
1561
1562 NUM_ACTUALS is the number of arguments.
1563
1564 ARGS is an array containing information for each argument; this
1565 routine fills in the INITIAL_VALUE and VALUE fields for each
1566 precomputed argument. */
1567
1568 static void
1569 precompute_arguments (int num_actuals, struct arg_data *args)
1570 {
1571 int i;
1572
1573 /* If this is a libcall, then precompute all arguments so that we do not
1574 get extraneous instructions emitted as part of the libcall sequence. */
1575
1576 /* If we preallocated the stack space, and some arguments must be passed
1577 on the stack, then we must precompute any parameter which contains a
1578 function call which will store arguments on the stack.
1579 Otherwise, evaluating the parameter may clobber previous parameters
1580 which have already been stored into the stack. (we have code to avoid
1581 such case by saving the outgoing stack arguments, but it results in
1582 worse code) */
1583 if (!ACCUMULATE_OUTGOING_ARGS)
1584 return;
1585
1586 for (i = 0; i < num_actuals; i++)
1587 {
1588 tree type;
1589 machine_mode mode;
1590
1591 if (TREE_CODE (args[i].tree_value) != CALL_EXPR)
1592 continue;
1593
1594 /* If this is an addressable type, we cannot pre-evaluate it. */
1595 type = TREE_TYPE (args[i].tree_value);
1596 gcc_assert (!TREE_ADDRESSABLE (type));
1597
1598 args[i].initial_value = args[i].value
1599 = expand_normal (args[i].tree_value);
1600
1601 mode = TYPE_MODE (type);
1602 if (mode != args[i].mode)
1603 {
1604 int unsignedp = args[i].unsignedp;
1605 args[i].value
1606 = convert_modes (args[i].mode, mode,
1607 args[i].value, args[i].unsignedp);
1608
1609 /* CSE will replace this only if it contains args[i].value
1610 pseudo, so convert it down to the declared mode using
1611 a SUBREG. */
1612 if (REG_P (args[i].value)
1613 && GET_MODE_CLASS (args[i].mode) == MODE_INT
1614 && promote_mode (type, mode, &unsignedp) != args[i].mode)
1615 {
1616 args[i].initial_value
1617 = gen_lowpart_SUBREG (mode, args[i].value);
1618 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1619 SUBREG_PROMOTED_SET (args[i].initial_value, args[i].unsignedp);
1620 }
1621 }
1622 }
1623 }
1624
1625 /* Given the current state of MUST_PREALLOCATE and information about
1626 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1627 compute and return the final value for MUST_PREALLOCATE. */
1628
1629 static int
1630 finalize_must_preallocate (int must_preallocate, int num_actuals,
1631 struct arg_data *args, struct args_size *args_size)
1632 {
1633 /* See if we have or want to preallocate stack space.
1634
1635 If we would have to push a partially-in-regs parm
1636 before other stack parms, preallocate stack space instead.
1637
1638 If the size of some parm is not a multiple of the required stack
1639 alignment, we must preallocate.
1640
1641 If the total size of arguments that would otherwise create a copy in
1642 a temporary (such as a CALL) is more than half the total argument list
1643 size, preallocation is faster.
1644
1645 Another reason to preallocate is if we have a machine (like the m88k)
1646 where stack alignment is required to be maintained between every
1647 pair of insns, not just when the call is made. However, we assume here
1648 that such machines either do not have push insns (and hence preallocation
1649 would occur anyway) or the problem is taken care of with
1650 PUSH_ROUNDING. */
1651
1652 if (! must_preallocate)
1653 {
1654 int partial_seen = 0;
1655 int copy_to_evaluate_size = 0;
1656 int i;
1657
1658 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1659 {
1660 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1661 partial_seen = 1;
1662 else if (partial_seen && args[i].reg == 0)
1663 must_preallocate = 1;
1664 /* We preallocate in case there are bounds passed
1665 in the bounds table to have precomputed address
1666 for bounds association. */
1667 else if (POINTER_BOUNDS_P (args[i].tree_value)
1668 && !args[i].reg)
1669 must_preallocate = 1;
1670
1671 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1672 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1673 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1674 || TREE_CODE (args[i].tree_value) == COND_EXPR
1675 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1676 copy_to_evaluate_size
1677 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1678 }
1679
1680 if (copy_to_evaluate_size * 2 >= args_size->constant
1681 && args_size->constant > 0)
1682 must_preallocate = 1;
1683 }
1684 return must_preallocate;
1685 }
1686
1687 /* If we preallocated stack space, compute the address of each argument
1688 and store it into the ARGS array.
1689
1690 We need not ensure it is a valid memory address here; it will be
1691 validized when it is used.
1692
1693 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1694
1695 static void
1696 compute_argument_addresses (struct arg_data *args, rtx argblock, int num_actuals)
1697 {
1698 if (argblock)
1699 {
1700 rtx arg_reg = argblock;
1701 int i, arg_offset = 0;
1702
1703 if (GET_CODE (argblock) == PLUS)
1704 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1705
1706 for (i = 0; i < num_actuals; i++)
1707 {
1708 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
1709 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
1710 rtx addr;
1711 unsigned int align, boundary;
1712 unsigned int units_on_stack = 0;
1713 machine_mode partial_mode = VOIDmode;
1714
1715 /* Skip this parm if it will not be passed on the stack. */
1716 if (! args[i].pass_on_stack
1717 && args[i].reg != 0
1718 && args[i].partial == 0)
1719 continue;
1720
1721 /* Pointer Bounds are never passed on the stack. */
1722 if (POINTER_BOUNDS_P (args[i].tree_value))
1723 continue;
1724
1725 if (CONST_INT_P (offset))
1726 addr = plus_constant (Pmode, arg_reg, INTVAL (offset));
1727 else
1728 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1729
1730 addr = plus_constant (Pmode, addr, arg_offset);
1731
1732 if (args[i].partial != 0)
1733 {
1734 /* Only part of the parameter is being passed on the stack.
1735 Generate a simple memory reference of the correct size. */
1736 units_on_stack = args[i].locate.size.constant;
1737 partial_mode = mode_for_size (units_on_stack * BITS_PER_UNIT,
1738 MODE_INT, 1);
1739 args[i].stack = gen_rtx_MEM (partial_mode, addr);
1740 set_mem_size (args[i].stack, units_on_stack);
1741 }
1742 else
1743 {
1744 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1745 set_mem_attributes (args[i].stack,
1746 TREE_TYPE (args[i].tree_value), 1);
1747 }
1748 align = BITS_PER_UNIT;
1749 boundary = args[i].locate.boundary;
1750 if (args[i].locate.where_pad != downward)
1751 align = boundary;
1752 else if (CONST_INT_P (offset))
1753 {
1754 align = INTVAL (offset) * BITS_PER_UNIT | boundary;
1755 align = align & -align;
1756 }
1757 set_mem_align (args[i].stack, align);
1758
1759 if (CONST_INT_P (slot_offset))
1760 addr = plus_constant (Pmode, arg_reg, INTVAL (slot_offset));
1761 else
1762 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1763
1764 addr = plus_constant (Pmode, addr, arg_offset);
1765
1766 if (args[i].partial != 0)
1767 {
1768 /* Only part of the parameter is being passed on the stack.
1769 Generate a simple memory reference of the correct size.
1770 */
1771 args[i].stack_slot = gen_rtx_MEM (partial_mode, addr);
1772 set_mem_size (args[i].stack_slot, units_on_stack);
1773 }
1774 else
1775 {
1776 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1777 set_mem_attributes (args[i].stack_slot,
1778 TREE_TYPE (args[i].tree_value), 1);
1779 }
1780 set_mem_align (args[i].stack_slot, args[i].locate.boundary);
1781
1782 /* Function incoming arguments may overlap with sibling call
1783 outgoing arguments and we cannot allow reordering of reads
1784 from function arguments with stores to outgoing arguments
1785 of sibling calls. */
1786 set_mem_alias_set (args[i].stack, 0);
1787 set_mem_alias_set (args[i].stack_slot, 0);
1788 }
1789 }
1790 }
1791
1792 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1793 in a call instruction.
1794
1795 FNDECL is the tree node for the target function. For an indirect call
1796 FNDECL will be NULL_TREE.
1797
1798 ADDR is the operand 0 of CALL_EXPR for this call. */
1799
1800 static rtx
1801 rtx_for_function_call (tree fndecl, tree addr)
1802 {
1803 rtx funexp;
1804
1805 /* Get the function to call, in the form of RTL. */
1806 if (fndecl)
1807 {
1808 if (!TREE_USED (fndecl) && fndecl != current_function_decl)
1809 TREE_USED (fndecl) = 1;
1810
1811 /* Get a SYMBOL_REF rtx for the function address. */
1812 funexp = XEXP (DECL_RTL (fndecl), 0);
1813 }
1814 else
1815 /* Generate an rtx (probably a pseudo-register) for the address. */
1816 {
1817 push_temp_slots ();
1818 funexp = expand_normal (addr);
1819 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1820 }
1821 return funexp;
1822 }
1823
1824 /* Internal state for internal_arg_pointer_based_exp and its helpers. */
1825 static struct
1826 {
1827 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
1828 or NULL_RTX if none has been scanned yet. */
1829 rtx_insn *scan_start;
1830 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
1831 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
1832 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
1833 with fixed offset, or PC if this is with variable or unknown offset. */
1834 vec<rtx> cache;
1835 } internal_arg_pointer_exp_state;
1836
1837 static rtx internal_arg_pointer_based_exp (const_rtx, bool);
1838
1839 /* Helper function for internal_arg_pointer_based_exp. Scan insns in
1840 the tail call sequence, starting with first insn that hasn't been
1841 scanned yet, and note for each pseudo on the LHS whether it is based
1842 on crtl->args.internal_arg_pointer or not, and what offset from that
1843 that pointer it has. */
1844
1845 static void
1846 internal_arg_pointer_based_exp_scan (void)
1847 {
1848 rtx_insn *insn, *scan_start = internal_arg_pointer_exp_state.scan_start;
1849
1850 if (scan_start == NULL_RTX)
1851 insn = get_insns ();
1852 else
1853 insn = NEXT_INSN (scan_start);
1854
1855 while (insn)
1856 {
1857 rtx set = single_set (insn);
1858 if (set && REG_P (SET_DEST (set)) && !HARD_REGISTER_P (SET_DEST (set)))
1859 {
1860 rtx val = NULL_RTX;
1861 unsigned int idx = REGNO (SET_DEST (set)) - FIRST_PSEUDO_REGISTER;
1862 /* Punt on pseudos set multiple times. */
1863 if (idx < internal_arg_pointer_exp_state.cache.length ()
1864 && (internal_arg_pointer_exp_state.cache[idx]
1865 != NULL_RTX))
1866 val = pc_rtx;
1867 else
1868 val = internal_arg_pointer_based_exp (SET_SRC (set), false);
1869 if (val != NULL_RTX)
1870 {
1871 if (idx >= internal_arg_pointer_exp_state.cache.length ())
1872 internal_arg_pointer_exp_state.cache
1873 .safe_grow_cleared (idx + 1);
1874 internal_arg_pointer_exp_state.cache[idx] = val;
1875 }
1876 }
1877 if (NEXT_INSN (insn) == NULL_RTX)
1878 scan_start = insn;
1879 insn = NEXT_INSN (insn);
1880 }
1881
1882 internal_arg_pointer_exp_state.scan_start = scan_start;
1883 }
1884
1885 /* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
1886 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
1887 it with fixed offset, or PC if this is with variable or unknown offset.
1888 TOPLEVEL is true if the function is invoked at the topmost level. */
1889
1890 static rtx
1891 internal_arg_pointer_based_exp (const_rtx rtl, bool toplevel)
1892 {
1893 if (CONSTANT_P (rtl))
1894 return NULL_RTX;
1895
1896 if (rtl == crtl->args.internal_arg_pointer)
1897 return const0_rtx;
1898
1899 if (REG_P (rtl) && HARD_REGISTER_P (rtl))
1900 return NULL_RTX;
1901
1902 if (GET_CODE (rtl) == PLUS && CONST_INT_P (XEXP (rtl, 1)))
1903 {
1904 rtx val = internal_arg_pointer_based_exp (XEXP (rtl, 0), toplevel);
1905 if (val == NULL_RTX || val == pc_rtx)
1906 return val;
1907 return plus_constant (Pmode, val, INTVAL (XEXP (rtl, 1)));
1908 }
1909
1910 /* When called at the topmost level, scan pseudo assignments in between the
1911 last scanned instruction in the tail call sequence and the latest insn
1912 in that sequence. */
1913 if (toplevel)
1914 internal_arg_pointer_based_exp_scan ();
1915
1916 if (REG_P (rtl))
1917 {
1918 unsigned int idx = REGNO (rtl) - FIRST_PSEUDO_REGISTER;
1919 if (idx < internal_arg_pointer_exp_state.cache.length ())
1920 return internal_arg_pointer_exp_state.cache[idx];
1921
1922 return NULL_RTX;
1923 }
1924
1925 subrtx_iterator::array_type array;
1926 FOR_EACH_SUBRTX (iter, array, rtl, NONCONST)
1927 {
1928 const_rtx x = *iter;
1929 if (REG_P (x) && internal_arg_pointer_based_exp (x, false) != NULL_RTX)
1930 return pc_rtx;
1931 if (MEM_P (x))
1932 iter.skip_subrtxes ();
1933 }
1934
1935 return NULL_RTX;
1936 }
1937
1938 /* Return true if and only if SIZE storage units (usually bytes)
1939 starting from address ADDR overlap with already clobbered argument
1940 area. This function is used to determine if we should give up a
1941 sibcall. */
1942
1943 static bool
1944 mem_overlaps_already_clobbered_arg_p (rtx addr, unsigned HOST_WIDE_INT size)
1945 {
1946 HOST_WIDE_INT i;
1947 rtx val;
1948
1949 if (bitmap_empty_p (stored_args_map))
1950 return false;
1951 val = internal_arg_pointer_based_exp (addr, true);
1952 if (val == NULL_RTX)
1953 return false;
1954 else if (val == pc_rtx)
1955 return true;
1956 else
1957 i = INTVAL (val);
1958
1959 if (STACK_GROWS_DOWNWARD)
1960 i -= crtl->args.pretend_args_size;
1961 else
1962 i += crtl->args.pretend_args_size;
1963
1964
1965 if (ARGS_GROW_DOWNWARD)
1966 i = -i - size;
1967
1968 if (size > 0)
1969 {
1970 unsigned HOST_WIDE_INT k;
1971
1972 for (k = 0; k < size; k++)
1973 if (i + k < SBITMAP_SIZE (stored_args_map)
1974 && bitmap_bit_p (stored_args_map, i + k))
1975 return true;
1976 }
1977
1978 return false;
1979 }
1980
1981 /* Do the register loads required for any wholly-register parms or any
1982 parms which are passed both on the stack and in a register. Their
1983 expressions were already evaluated.
1984
1985 Mark all register-parms as living through the call, putting these USE
1986 insns in the CALL_INSN_FUNCTION_USAGE field.
1987
1988 When IS_SIBCALL, perform the check_sibcall_argument_overlap
1989 checking, setting *SIBCALL_FAILURE if appropriate. */
1990
1991 static void
1992 load_register_parameters (struct arg_data *args, int num_actuals,
1993 rtx *call_fusage, int flags, int is_sibcall,
1994 int *sibcall_failure)
1995 {
1996 int i, j;
1997
1998 for (i = 0; i < num_actuals; i++)
1999 {
2000 rtx reg = ((flags & ECF_SIBCALL)
2001 ? args[i].tail_call_reg : args[i].reg);
2002 if (reg)
2003 {
2004 int partial = args[i].partial;
2005 int nregs;
2006 int size = 0;
2007 rtx_insn *before_arg = get_last_insn ();
2008 /* Set non-negative if we must move a word at a time, even if
2009 just one word (e.g, partial == 4 && mode == DFmode). Set
2010 to -1 if we just use a normal move insn. This value can be
2011 zero if the argument is a zero size structure. */
2012 nregs = -1;
2013 if (GET_CODE (reg) == PARALLEL)
2014 ;
2015 else if (partial)
2016 {
2017 gcc_assert (partial % UNITS_PER_WORD == 0);
2018 nregs = partial / UNITS_PER_WORD;
2019 }
2020 else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
2021 {
2022 size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
2023 nregs = (size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
2024 }
2025 else
2026 size = GET_MODE_SIZE (args[i].mode);
2027
2028 /* Handle calls that pass values in multiple non-contiguous
2029 locations. The Irix 6 ABI has examples of this. */
2030
2031 if (GET_CODE (reg) == PARALLEL)
2032 emit_group_move (reg, args[i].parallel_value);
2033
2034 /* If simple case, just do move. If normal partial, store_one_arg
2035 has already loaded the register for us. In all other cases,
2036 load the register(s) from memory. */
2037
2038 else if (nregs == -1)
2039 {
2040 emit_move_insn (reg, args[i].value);
2041 #ifdef BLOCK_REG_PADDING
2042 /* Handle case where we have a value that needs shifting
2043 up to the msb. eg. a QImode value and we're padding
2044 upward on a BYTES_BIG_ENDIAN machine. */
2045 if (size < UNITS_PER_WORD
2046 && (args[i].locate.where_pad
2047 == (BYTES_BIG_ENDIAN ? upward : downward)))
2048 {
2049 rtx x;
2050 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2051
2052 /* Assigning REG here rather than a temp makes CALL_FUSAGE
2053 report the whole reg as used. Strictly speaking, the
2054 call only uses SIZE bytes at the msb end, but it doesn't
2055 seem worth generating rtl to say that. */
2056 reg = gen_rtx_REG (word_mode, REGNO (reg));
2057 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
2058 if (x != reg)
2059 emit_move_insn (reg, x);
2060 }
2061 #endif
2062 }
2063
2064 /* If we have pre-computed the values to put in the registers in
2065 the case of non-aligned structures, copy them in now. */
2066
2067 else if (args[i].n_aligned_regs != 0)
2068 for (j = 0; j < args[i].n_aligned_regs; j++)
2069 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
2070 args[i].aligned_regs[j]);
2071
2072 else if (partial == 0 || args[i].pass_on_stack)
2073 {
2074 rtx mem = validize_mem (copy_rtx (args[i].value));
2075
2076 /* Check for overlap with already clobbered argument area,
2077 providing that this has non-zero size. */
2078 if (is_sibcall
2079 && (size == 0
2080 || mem_overlaps_already_clobbered_arg_p
2081 (XEXP (args[i].value, 0), size)))
2082 *sibcall_failure = 1;
2083
2084 if (size % UNITS_PER_WORD == 0
2085 || MEM_ALIGN (mem) % BITS_PER_WORD == 0)
2086 move_block_to_reg (REGNO (reg), mem, nregs, args[i].mode);
2087 else
2088 {
2089 if (nregs > 1)
2090 move_block_to_reg (REGNO (reg), mem, nregs - 1,
2091 args[i].mode);
2092 rtx dest = gen_rtx_REG (word_mode, REGNO (reg) + nregs - 1);
2093 unsigned int bitoff = (nregs - 1) * BITS_PER_WORD;
2094 unsigned int bitsize = size * BITS_PER_UNIT - bitoff;
2095 rtx x = extract_bit_field (mem, bitsize, bitoff, 1, dest,
2096 word_mode, word_mode, false);
2097 if (BYTES_BIG_ENDIAN)
2098 x = expand_shift (LSHIFT_EXPR, word_mode, x,
2099 BITS_PER_WORD - bitsize, dest, 1);
2100 if (x != dest)
2101 emit_move_insn (dest, x);
2102 }
2103
2104 /* Handle a BLKmode that needs shifting. */
2105 if (nregs == 1 && size < UNITS_PER_WORD
2106 #ifdef BLOCK_REG_PADDING
2107 && args[i].locate.where_pad == downward
2108 #else
2109 && BYTES_BIG_ENDIAN
2110 #endif
2111 )
2112 {
2113 rtx dest = gen_rtx_REG (word_mode, REGNO (reg));
2114 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2115 enum tree_code dir = (BYTES_BIG_ENDIAN
2116 ? RSHIFT_EXPR : LSHIFT_EXPR);
2117 rtx x;
2118
2119 x = expand_shift (dir, word_mode, dest, shift, dest, 1);
2120 if (x != dest)
2121 emit_move_insn (dest, x);
2122 }
2123 }
2124
2125 /* When a parameter is a block, and perhaps in other cases, it is
2126 possible that it did a load from an argument slot that was
2127 already clobbered. */
2128 if (is_sibcall
2129 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
2130 *sibcall_failure = 1;
2131
2132 /* Handle calls that pass values in multiple non-contiguous
2133 locations. The Irix 6 ABI has examples of this. */
2134 if (GET_CODE (reg) == PARALLEL)
2135 use_group_regs (call_fusage, reg);
2136 else if (nregs == -1)
2137 use_reg_mode (call_fusage, reg,
2138 TYPE_MODE (TREE_TYPE (args[i].tree_value)));
2139 else if (nregs > 0)
2140 use_regs (call_fusage, REGNO (reg), nregs);
2141 }
2142 }
2143 }
2144
2145 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
2146 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
2147 bytes, then we would need to push some additional bytes to pad the
2148 arguments. So, we compute an adjust to the stack pointer for an
2149 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
2150 bytes. Then, when the arguments are pushed the stack will be perfectly
2151 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
2152 be popped after the call. Returns the adjustment. */
2153
2154 static int
2155 combine_pending_stack_adjustment_and_call (int unadjusted_args_size,
2156 struct args_size *args_size,
2157 unsigned int preferred_unit_stack_boundary)
2158 {
2159 /* The number of bytes to pop so that the stack will be
2160 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
2161 HOST_WIDE_INT adjustment;
2162 /* The alignment of the stack after the arguments are pushed, if we
2163 just pushed the arguments without adjust the stack here. */
2164 unsigned HOST_WIDE_INT unadjusted_alignment;
2165
2166 unadjusted_alignment
2167 = ((stack_pointer_delta + unadjusted_args_size)
2168 % preferred_unit_stack_boundary);
2169
2170 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
2171 as possible -- leaving just enough left to cancel out the
2172 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
2173 PENDING_STACK_ADJUST is non-negative, and congruent to
2174 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
2175
2176 /* Begin by trying to pop all the bytes. */
2177 unadjusted_alignment
2178 = (unadjusted_alignment
2179 - (pending_stack_adjust % preferred_unit_stack_boundary));
2180 adjustment = pending_stack_adjust;
2181 /* Push enough additional bytes that the stack will be aligned
2182 after the arguments are pushed. */
2183 if (preferred_unit_stack_boundary > 1)
2184 {
2185 if (unadjusted_alignment > 0)
2186 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
2187 else
2188 adjustment += unadjusted_alignment;
2189 }
2190
2191 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
2192 bytes after the call. The right number is the entire
2193 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
2194 by the arguments in the first place. */
2195 args_size->constant
2196 = pending_stack_adjust - adjustment + unadjusted_args_size;
2197
2198 return adjustment;
2199 }
2200
2201 /* Scan X expression if it does not dereference any argument slots
2202 we already clobbered by tail call arguments (as noted in stored_args_map
2203 bitmap).
2204 Return nonzero if X expression dereferences such argument slots,
2205 zero otherwise. */
2206
2207 static int
2208 check_sibcall_argument_overlap_1 (rtx x)
2209 {
2210 RTX_CODE code;
2211 int i, j;
2212 const char *fmt;
2213
2214 if (x == NULL_RTX)
2215 return 0;
2216
2217 code = GET_CODE (x);
2218
2219 /* We need not check the operands of the CALL expression itself. */
2220 if (code == CALL)
2221 return 0;
2222
2223 if (code == MEM)
2224 return mem_overlaps_already_clobbered_arg_p (XEXP (x, 0),
2225 GET_MODE_SIZE (GET_MODE (x)));
2226
2227 /* Scan all subexpressions. */
2228 fmt = GET_RTX_FORMAT (code);
2229 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2230 {
2231 if (*fmt == 'e')
2232 {
2233 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2234 return 1;
2235 }
2236 else if (*fmt == 'E')
2237 {
2238 for (j = 0; j < XVECLEN (x, i); j++)
2239 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2240 return 1;
2241 }
2242 }
2243 return 0;
2244 }
2245
2246 /* Scan sequence after INSN if it does not dereference any argument slots
2247 we already clobbered by tail call arguments (as noted in stored_args_map
2248 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
2249 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
2250 should be 0). Return nonzero if sequence after INSN dereferences such argument
2251 slots, zero otherwise. */
2252
2253 static int
2254 check_sibcall_argument_overlap (rtx_insn *insn, struct arg_data *arg,
2255 int mark_stored_args_map)
2256 {
2257 int low, high;
2258
2259 if (insn == NULL_RTX)
2260 insn = get_insns ();
2261 else
2262 insn = NEXT_INSN (insn);
2263
2264 for (; insn; insn = NEXT_INSN (insn))
2265 if (INSN_P (insn)
2266 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2267 break;
2268
2269 if (mark_stored_args_map)
2270 {
2271 if (ARGS_GROW_DOWNWARD)
2272 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
2273 else
2274 low = arg->locate.slot_offset.constant;
2275
2276 for (high = low + arg->locate.size.constant; low < high; low++)
2277 bitmap_set_bit (stored_args_map, low);
2278 }
2279 return insn != NULL_RTX;
2280 }
2281
2282 /* Given that a function returns a value of mode MODE at the most
2283 significant end of hard register VALUE, shift VALUE left or right
2284 as specified by LEFT_P. Return true if some action was needed. */
2285
2286 bool
2287 shift_return_value (machine_mode mode, bool left_p, rtx value)
2288 {
2289 HOST_WIDE_INT shift;
2290
2291 gcc_assert (REG_P (value) && HARD_REGISTER_P (value));
2292 shift = GET_MODE_BITSIZE (GET_MODE (value)) - GET_MODE_BITSIZE (mode);
2293 if (shift == 0)
2294 return false;
2295
2296 /* Use ashr rather than lshr for right shifts. This is for the benefit
2297 of the MIPS port, which requires SImode values to be sign-extended
2298 when stored in 64-bit registers. */
2299 if (!force_expand_binop (GET_MODE (value), left_p ? ashl_optab : ashr_optab,
2300 value, GEN_INT (shift), value, 1, OPTAB_WIDEN))
2301 gcc_unreachable ();
2302 return true;
2303 }
2304
2305 /* If X is a likely-spilled register value, copy it to a pseudo
2306 register and return that register. Return X otherwise. */
2307
2308 static rtx
2309 avoid_likely_spilled_reg (rtx x)
2310 {
2311 rtx new_rtx;
2312
2313 if (REG_P (x)
2314 && HARD_REGISTER_P (x)
2315 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x))))
2316 {
2317 /* Make sure that we generate a REG rather than a CONCAT.
2318 Moves into CONCATs can need nontrivial instructions,
2319 and the whole point of this function is to avoid
2320 using the hard register directly in such a situation. */
2321 generating_concat_p = 0;
2322 new_rtx = gen_reg_rtx (GET_MODE (x));
2323 generating_concat_p = 1;
2324 emit_move_insn (new_rtx, x);
2325 return new_rtx;
2326 }
2327 return x;
2328 }
2329
2330 /* Generate all the code for a CALL_EXPR exp
2331 and return an rtx for its value.
2332 Store the value in TARGET (specified as an rtx) if convenient.
2333 If the value is stored in TARGET then TARGET is returned.
2334 If IGNORE is nonzero, then we ignore the value of the function call. */
2335
2336 rtx
2337 expand_call (tree exp, rtx target, int ignore)
2338 {
2339 /* Nonzero if we are currently expanding a call. */
2340 static int currently_expanding_call = 0;
2341
2342 /* RTX for the function to be called. */
2343 rtx funexp;
2344 /* Sequence of insns to perform a normal "call". */
2345 rtx_insn *normal_call_insns = NULL;
2346 /* Sequence of insns to perform a tail "call". */
2347 rtx_insn *tail_call_insns = NULL;
2348 /* Data type of the function. */
2349 tree funtype;
2350 tree type_arg_types;
2351 tree rettype;
2352 /* Declaration of the function being called,
2353 or 0 if the function is computed (not known by name). */
2354 tree fndecl = 0;
2355 /* The type of the function being called. */
2356 tree fntype;
2357 bool try_tail_call = CALL_EXPR_TAILCALL (exp);
2358 int pass;
2359
2360 /* Register in which non-BLKmode value will be returned,
2361 or 0 if no value or if value is BLKmode. */
2362 rtx valreg;
2363 /* Register(s) in which bounds are returned. */
2364 rtx valbnd = NULL;
2365 /* Address where we should return a BLKmode value;
2366 0 if value not BLKmode. */
2367 rtx structure_value_addr = 0;
2368 /* Nonzero if that address is being passed by treating it as
2369 an extra, implicit first parameter. Otherwise,
2370 it is passed by being copied directly into struct_value_rtx. */
2371 int structure_value_addr_parm = 0;
2372 /* Holds the value of implicit argument for the struct value. */
2373 tree structure_value_addr_value = NULL_TREE;
2374 /* Size of aggregate value wanted, or zero if none wanted
2375 or if we are using the non-reentrant PCC calling convention
2376 or expecting the value in registers. */
2377 HOST_WIDE_INT struct_value_size = 0;
2378 /* Nonzero if called function returns an aggregate in memory PCC style,
2379 by returning the address of where to find it. */
2380 int pcc_struct_value = 0;
2381 rtx struct_value = 0;
2382
2383 /* Number of actual parameters in this call, including struct value addr. */
2384 int num_actuals;
2385 /* Number of named args. Args after this are anonymous ones
2386 and they must all go on the stack. */
2387 int n_named_args;
2388 /* Number of complex actual arguments that need to be split. */
2389 int num_complex_actuals = 0;
2390
2391 /* Vector of information about each argument.
2392 Arguments are numbered in the order they will be pushed,
2393 not the order they are written. */
2394 struct arg_data *args;
2395
2396 /* Total size in bytes of all the stack-parms scanned so far. */
2397 struct args_size args_size;
2398 struct args_size adjusted_args_size;
2399 /* Size of arguments before any adjustments (such as rounding). */
2400 int unadjusted_args_size;
2401 /* Data on reg parms scanned so far. */
2402 CUMULATIVE_ARGS args_so_far_v;
2403 cumulative_args_t args_so_far;
2404 /* Nonzero if a reg parm has been scanned. */
2405 int reg_parm_seen;
2406 /* Nonzero if this is an indirect function call. */
2407
2408 /* Nonzero if we must avoid push-insns in the args for this call.
2409 If stack space is allocated for register parameters, but not by the
2410 caller, then it is preallocated in the fixed part of the stack frame.
2411 So the entire argument block must then be preallocated (i.e., we
2412 ignore PUSH_ROUNDING in that case). */
2413
2414 int must_preallocate = !PUSH_ARGS;
2415
2416 /* Size of the stack reserved for parameter registers. */
2417 int reg_parm_stack_space = 0;
2418
2419 /* Address of space preallocated for stack parms
2420 (on machines that lack push insns), or 0 if space not preallocated. */
2421 rtx argblock = 0;
2422
2423 /* Mask of ECF_ and ERF_ flags. */
2424 int flags = 0;
2425 int return_flags = 0;
2426 #ifdef REG_PARM_STACK_SPACE
2427 /* Define the boundary of the register parm stack space that needs to be
2428 saved, if any. */
2429 int low_to_save, high_to_save;
2430 rtx save_area = 0; /* Place that it is saved */
2431 #endif
2432
2433 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2434 char *initial_stack_usage_map = stack_usage_map;
2435 char *stack_usage_map_buf = NULL;
2436
2437 int old_stack_allocated;
2438
2439 /* State variables to track stack modifications. */
2440 rtx old_stack_level = 0;
2441 int old_stack_arg_under_construction = 0;
2442 int old_pending_adj = 0;
2443 int old_inhibit_defer_pop = inhibit_defer_pop;
2444
2445 /* Some stack pointer alterations we make are performed via
2446 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
2447 which we then also need to save/restore along the way. */
2448 int old_stack_pointer_delta = 0;
2449
2450 rtx call_fusage;
2451 tree addr = CALL_EXPR_FN (exp);
2452 int i;
2453 /* The alignment of the stack, in bits. */
2454 unsigned HOST_WIDE_INT preferred_stack_boundary;
2455 /* The alignment of the stack, in bytes. */
2456 unsigned HOST_WIDE_INT preferred_unit_stack_boundary;
2457 /* The static chain value to use for this call. */
2458 rtx static_chain_value;
2459 /* See if this is "nothrow" function call. */
2460 if (TREE_NOTHROW (exp))
2461 flags |= ECF_NOTHROW;
2462
2463 /* See if we can find a DECL-node for the actual function, and get the
2464 function attributes (flags) from the function decl or type node. */
2465 fndecl = get_callee_fndecl (exp);
2466 if (fndecl)
2467 {
2468 fntype = TREE_TYPE (fndecl);
2469 flags |= flags_from_decl_or_type (fndecl);
2470 return_flags |= decl_return_flags (fndecl);
2471 }
2472 else
2473 {
2474 fntype = TREE_TYPE (TREE_TYPE (addr));
2475 flags |= flags_from_decl_or_type (fntype);
2476 }
2477 rettype = TREE_TYPE (exp);
2478
2479 struct_value = targetm.calls.struct_value_rtx (fntype, 0);
2480
2481 /* Warn if this value is an aggregate type,
2482 regardless of which calling convention we are using for it. */
2483 if (AGGREGATE_TYPE_P (rettype))
2484 warning (OPT_Waggregate_return, "function call has aggregate value");
2485
2486 /* If the result of a non looping pure or const function call is
2487 ignored (or void), and none of its arguments are volatile, we can
2488 avoid expanding the call and just evaluate the arguments for
2489 side-effects. */
2490 if ((flags & (ECF_CONST | ECF_PURE))
2491 && (!(flags & ECF_LOOPING_CONST_OR_PURE))
2492 && (ignore || target == const0_rtx
2493 || TYPE_MODE (rettype) == VOIDmode))
2494 {
2495 bool volatilep = false;
2496 tree arg;
2497 call_expr_arg_iterator iter;
2498
2499 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2500 if (TREE_THIS_VOLATILE (arg))
2501 {
2502 volatilep = true;
2503 break;
2504 }
2505
2506 if (! volatilep)
2507 {
2508 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2509 expand_expr (arg, const0_rtx, VOIDmode, EXPAND_NORMAL);
2510 return const0_rtx;
2511 }
2512 }
2513
2514 #ifdef REG_PARM_STACK_SPACE
2515 reg_parm_stack_space = REG_PARM_STACK_SPACE (!fndecl ? fntype : fndecl);
2516 #endif
2517
2518 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
2519 && reg_parm_stack_space > 0 && PUSH_ARGS)
2520 must_preallocate = 1;
2521
2522 /* Set up a place to return a structure. */
2523
2524 /* Cater to broken compilers. */
2525 if (aggregate_value_p (exp, fntype))
2526 {
2527 /* This call returns a big structure. */
2528 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
2529
2530 #ifdef PCC_STATIC_STRUCT_RETURN
2531 {
2532 pcc_struct_value = 1;
2533 }
2534 #else /* not PCC_STATIC_STRUCT_RETURN */
2535 {
2536 struct_value_size = int_size_in_bytes (rettype);
2537
2538 /* Even if it is semantically safe to use the target as the return
2539 slot, it may be not sufficiently aligned for the return type. */
2540 if (CALL_EXPR_RETURN_SLOT_OPT (exp)
2541 && target
2542 && MEM_P (target)
2543 && !(MEM_ALIGN (target) < TYPE_ALIGN (rettype)
2544 && SLOW_UNALIGNED_ACCESS (TYPE_MODE (rettype),
2545 MEM_ALIGN (target))))
2546 structure_value_addr = XEXP (target, 0);
2547 else
2548 {
2549 /* For variable-sized objects, we must be called with a target
2550 specified. If we were to allocate space on the stack here,
2551 we would have no way of knowing when to free it. */
2552 rtx d = assign_temp (rettype, 1, 1);
2553 structure_value_addr = XEXP (d, 0);
2554 target = 0;
2555 }
2556 }
2557 #endif /* not PCC_STATIC_STRUCT_RETURN */
2558 }
2559
2560 /* Figure out the amount to which the stack should be aligned. */
2561 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2562 if (fndecl)
2563 {
2564 struct cgraph_rtl_info *i = cgraph_node::rtl_info (fndecl);
2565 /* Without automatic stack alignment, we can't increase preferred
2566 stack boundary. With automatic stack alignment, it is
2567 unnecessary since unless we can guarantee that all callers will
2568 align the outgoing stack properly, callee has to align its
2569 stack anyway. */
2570 if (i
2571 && i->preferred_incoming_stack_boundary
2572 && i->preferred_incoming_stack_boundary < preferred_stack_boundary)
2573 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
2574 }
2575
2576 /* Operand 0 is a pointer-to-function; get the type of the function. */
2577 funtype = TREE_TYPE (addr);
2578 gcc_assert (POINTER_TYPE_P (funtype));
2579 funtype = TREE_TYPE (funtype);
2580
2581 /* Count whether there are actual complex arguments that need to be split
2582 into their real and imaginary parts. Munge the type_arg_types
2583 appropriately here as well. */
2584 if (targetm.calls.split_complex_arg)
2585 {
2586 call_expr_arg_iterator iter;
2587 tree arg;
2588 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2589 {
2590 tree type = TREE_TYPE (arg);
2591 if (type && TREE_CODE (type) == COMPLEX_TYPE
2592 && targetm.calls.split_complex_arg (type))
2593 num_complex_actuals++;
2594 }
2595 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
2596 }
2597 else
2598 type_arg_types = TYPE_ARG_TYPES (funtype);
2599
2600 if (flags & ECF_MAY_BE_ALLOCA)
2601 cfun->calls_alloca = 1;
2602
2603 /* If struct_value_rtx is 0, it means pass the address
2604 as if it were an extra parameter. Put the argument expression
2605 in structure_value_addr_value. */
2606 if (structure_value_addr && struct_value == 0)
2607 {
2608 /* If structure_value_addr is a REG other than
2609 virtual_outgoing_args_rtx, we can use always use it. If it
2610 is not a REG, we must always copy it into a register.
2611 If it is virtual_outgoing_args_rtx, we must copy it to another
2612 register in some cases. */
2613 rtx temp = (!REG_P (structure_value_addr)
2614 || (ACCUMULATE_OUTGOING_ARGS
2615 && stack_arg_under_construction
2616 && structure_value_addr == virtual_outgoing_args_rtx)
2617 ? copy_addr_to_reg (convert_memory_address
2618 (Pmode, structure_value_addr))
2619 : structure_value_addr);
2620
2621 structure_value_addr_value =
2622 make_tree (build_pointer_type (TREE_TYPE (funtype)), temp);
2623 structure_value_addr_parm = CALL_WITH_BOUNDS_P (exp) ? 2 : 1;
2624 }
2625
2626 /* Count the arguments and set NUM_ACTUALS. */
2627 num_actuals =
2628 call_expr_nargs (exp) + num_complex_actuals + structure_value_addr_parm;
2629
2630 /* Compute number of named args.
2631 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
2632
2633 if (type_arg_types != 0)
2634 n_named_args
2635 = (list_length (type_arg_types)
2636 /* Count the struct value address, if it is passed as a parm. */
2637 + structure_value_addr_parm);
2638 else
2639 /* If we know nothing, treat all args as named. */
2640 n_named_args = num_actuals;
2641
2642 /* Start updating where the next arg would go.
2643
2644 On some machines (such as the PA) indirect calls have a different
2645 calling convention than normal calls. The fourth argument in
2646 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2647 or not. */
2648 INIT_CUMULATIVE_ARGS (args_so_far_v, funtype, NULL_RTX, fndecl, n_named_args);
2649 args_so_far = pack_cumulative_args (&args_so_far_v);
2650
2651 /* Now possibly adjust the number of named args.
2652 Normally, don't include the last named arg if anonymous args follow.
2653 We do include the last named arg if
2654 targetm.calls.strict_argument_naming() returns nonzero.
2655 (If no anonymous args follow, the result of list_length is actually
2656 one too large. This is harmless.)
2657
2658 If targetm.calls.pretend_outgoing_varargs_named() returns
2659 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2660 this machine will be able to place unnamed args that were passed
2661 in registers into the stack. So treat all args as named. This
2662 allows the insns emitting for a specific argument list to be
2663 independent of the function declaration.
2664
2665 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2666 we do not have any reliable way to pass unnamed args in
2667 registers, so we must force them into memory. */
2668
2669 if (type_arg_types != 0
2670 && targetm.calls.strict_argument_naming (args_so_far))
2671 ;
2672 else if (type_arg_types != 0
2673 && ! targetm.calls.pretend_outgoing_varargs_named (args_so_far))
2674 /* Don't include the last named arg. */
2675 --n_named_args;
2676 else
2677 /* Treat all args as named. */
2678 n_named_args = num_actuals;
2679
2680 /* Make a vector to hold all the information about each arg. */
2681 args = XALLOCAVEC (struct arg_data, num_actuals);
2682 memset (args, 0, num_actuals * sizeof (struct arg_data));
2683
2684 /* Build up entries in the ARGS array, compute the size of the
2685 arguments into ARGS_SIZE, etc. */
2686 initialize_argument_information (num_actuals, args, &args_size,
2687 n_named_args, exp,
2688 structure_value_addr_value, fndecl, fntype,
2689 args_so_far, reg_parm_stack_space,
2690 &old_stack_level, &old_pending_adj,
2691 &must_preallocate, &flags,
2692 &try_tail_call, CALL_FROM_THUNK_P (exp));
2693
2694 if (args_size.var)
2695 must_preallocate = 1;
2696
2697 /* Now make final decision about preallocating stack space. */
2698 must_preallocate = finalize_must_preallocate (must_preallocate,
2699 num_actuals, args,
2700 &args_size);
2701
2702 /* If the structure value address will reference the stack pointer, we
2703 must stabilize it. We don't need to do this if we know that we are
2704 not going to adjust the stack pointer in processing this call. */
2705
2706 if (structure_value_addr
2707 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2708 || reg_mentioned_p (virtual_outgoing_args_rtx,
2709 structure_value_addr))
2710 && (args_size.var
2711 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2712 structure_value_addr = copy_to_reg (structure_value_addr);
2713
2714 /* Tail calls can make things harder to debug, and we've traditionally
2715 pushed these optimizations into -O2. Don't try if we're already
2716 expanding a call, as that means we're an argument. Don't try if
2717 there's cleanups, as we know there's code to follow the call. */
2718
2719 if (currently_expanding_call++ != 0
2720 || !flag_optimize_sibling_calls
2721 || args_size.var
2722 || dbg_cnt (tail_call) == false)
2723 try_tail_call = 0;
2724
2725 /* Rest of purposes for tail call optimizations to fail. */
2726 if (!try_tail_call
2727 || !targetm.have_sibcall_epilogue ()
2728 /* Doing sibling call optimization needs some work, since
2729 structure_value_addr can be allocated on the stack.
2730 It does not seem worth the effort since few optimizable
2731 sibling calls will return a structure. */
2732 || structure_value_addr != NULL_RTX
2733 #ifdef REG_PARM_STACK_SPACE
2734 /* If outgoing reg parm stack space changes, we can not do sibcall. */
2735 || (OUTGOING_REG_PARM_STACK_SPACE (funtype)
2736 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl)))
2737 || (reg_parm_stack_space != REG_PARM_STACK_SPACE (current_function_decl))
2738 #endif
2739 /* Check whether the target is able to optimize the call
2740 into a sibcall. */
2741 || !targetm.function_ok_for_sibcall (fndecl, exp)
2742 /* Functions that do not return exactly once may not be sibcall
2743 optimized. */
2744 || (flags & (ECF_RETURNS_TWICE | ECF_NORETURN))
2745 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr)))
2746 /* If the called function is nested in the current one, it might access
2747 some of the caller's arguments, but could clobber them beforehand if
2748 the argument areas are shared. */
2749 || (fndecl && decl_function_context (fndecl) == current_function_decl)
2750 /* If this function requires more stack slots than the current
2751 function, we cannot change it into a sibling call.
2752 crtl->args.pretend_args_size is not part of the
2753 stack allocated by our caller. */
2754 || args_size.constant > (crtl->args.size
2755 - crtl->args.pretend_args_size)
2756 /* If the callee pops its own arguments, then it must pop exactly
2757 the same number of arguments as the current function. */
2758 || (targetm.calls.return_pops_args (fndecl, funtype, args_size.constant)
2759 != targetm.calls.return_pops_args (current_function_decl,
2760 TREE_TYPE (current_function_decl),
2761 crtl->args.size))
2762 || !lang_hooks.decls.ok_for_sibcall (fndecl))
2763 try_tail_call = 0;
2764
2765 /* Check if caller and callee disagree in promotion of function
2766 return value. */
2767 if (try_tail_call)
2768 {
2769 machine_mode caller_mode, caller_promoted_mode;
2770 machine_mode callee_mode, callee_promoted_mode;
2771 int caller_unsignedp, callee_unsignedp;
2772 tree caller_res = DECL_RESULT (current_function_decl);
2773
2774 caller_unsignedp = TYPE_UNSIGNED (TREE_TYPE (caller_res));
2775 caller_mode = DECL_MODE (caller_res);
2776 callee_unsignedp = TYPE_UNSIGNED (TREE_TYPE (funtype));
2777 callee_mode = TYPE_MODE (TREE_TYPE (funtype));
2778 caller_promoted_mode
2779 = promote_function_mode (TREE_TYPE (caller_res), caller_mode,
2780 &caller_unsignedp,
2781 TREE_TYPE (current_function_decl), 1);
2782 callee_promoted_mode
2783 = promote_function_mode (TREE_TYPE (funtype), callee_mode,
2784 &callee_unsignedp,
2785 funtype, 1);
2786 if (caller_mode != VOIDmode
2787 && (caller_promoted_mode != callee_promoted_mode
2788 || ((caller_mode != caller_promoted_mode
2789 || callee_mode != callee_promoted_mode)
2790 && (caller_unsignedp != callee_unsignedp
2791 || GET_MODE_BITSIZE (caller_mode)
2792 < GET_MODE_BITSIZE (callee_mode)))))
2793 try_tail_call = 0;
2794 }
2795
2796 /* Ensure current function's preferred stack boundary is at least
2797 what we need. Stack alignment may also increase preferred stack
2798 boundary. */
2799 if (crtl->preferred_stack_boundary < preferred_stack_boundary)
2800 crtl->preferred_stack_boundary = preferred_stack_boundary;
2801 else
2802 preferred_stack_boundary = crtl->preferred_stack_boundary;
2803
2804 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2805
2806 /* We want to make two insn chains; one for a sibling call, the other
2807 for a normal call. We will select one of the two chains after
2808 initial RTL generation is complete. */
2809 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
2810 {
2811 int sibcall_failure = 0;
2812 /* We want to emit any pending stack adjustments before the tail
2813 recursion "call". That way we know any adjustment after the tail
2814 recursion call can be ignored if we indeed use the tail
2815 call expansion. */
2816 saved_pending_stack_adjust save;
2817 rtx_insn *insns, *before_call, *after_args;
2818 rtx next_arg_reg;
2819
2820 if (pass == 0)
2821 {
2822 /* State variables we need to save and restore between
2823 iterations. */
2824 save_pending_stack_adjust (&save);
2825 }
2826 if (pass)
2827 flags &= ~ECF_SIBCALL;
2828 else
2829 flags |= ECF_SIBCALL;
2830
2831 /* Other state variables that we must reinitialize each time
2832 through the loop (that are not initialized by the loop itself). */
2833 argblock = 0;
2834 call_fusage = 0;
2835
2836 /* Start a new sequence for the normal call case.
2837
2838 From this point on, if the sibling call fails, we want to set
2839 sibcall_failure instead of continuing the loop. */
2840 start_sequence ();
2841
2842 /* Don't let pending stack adjusts add up to too much.
2843 Also, do all pending adjustments now if there is any chance
2844 this might be a call to alloca or if we are expanding a sibling
2845 call sequence.
2846 Also do the adjustments before a throwing call, otherwise
2847 exception handling can fail; PR 19225. */
2848 if (pending_stack_adjust >= 32
2849 || (pending_stack_adjust > 0
2850 && (flags & ECF_MAY_BE_ALLOCA))
2851 || (pending_stack_adjust > 0
2852 && flag_exceptions && !(flags & ECF_NOTHROW))
2853 || pass == 0)
2854 do_pending_stack_adjust ();
2855
2856 /* Precompute any arguments as needed. */
2857 if (pass)
2858 precompute_arguments (num_actuals, args);
2859
2860 /* Now we are about to start emitting insns that can be deleted
2861 if a libcall is deleted. */
2862 if (pass && (flags & ECF_MALLOC))
2863 start_sequence ();
2864
2865 if (pass == 0 && crtl->stack_protect_guard)
2866 stack_protect_epilogue ();
2867
2868 adjusted_args_size = args_size;
2869 /* Compute the actual size of the argument block required. The variable
2870 and constant sizes must be combined, the size may have to be rounded,
2871 and there may be a minimum required size. When generating a sibcall
2872 pattern, do not round up, since we'll be re-using whatever space our
2873 caller provided. */
2874 unadjusted_args_size
2875 = compute_argument_block_size (reg_parm_stack_space,
2876 &adjusted_args_size,
2877 fndecl, fntype,
2878 (pass == 0 ? 0
2879 : preferred_stack_boundary));
2880
2881 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2882
2883 /* The argument block when performing a sibling call is the
2884 incoming argument block. */
2885 if (pass == 0)
2886 {
2887 argblock = crtl->args.internal_arg_pointer;
2888 if (STACK_GROWS_DOWNWARD)
2889 argblock
2890 = plus_constant (Pmode, argblock, crtl->args.pretend_args_size);
2891 else
2892 argblock
2893 = plus_constant (Pmode, argblock, -crtl->args.pretend_args_size);
2894
2895 stored_args_map = sbitmap_alloc (args_size.constant);
2896 bitmap_clear (stored_args_map);
2897 }
2898
2899 /* If we have no actual push instructions, or shouldn't use them,
2900 make space for all args right now. */
2901 else if (adjusted_args_size.var != 0)
2902 {
2903 if (old_stack_level == 0)
2904 {
2905 emit_stack_save (SAVE_BLOCK, &old_stack_level);
2906 old_stack_pointer_delta = stack_pointer_delta;
2907 old_pending_adj = pending_stack_adjust;
2908 pending_stack_adjust = 0;
2909 /* stack_arg_under_construction says whether a stack arg is
2910 being constructed at the old stack level. Pushing the stack
2911 gets a clean outgoing argument block. */
2912 old_stack_arg_under_construction = stack_arg_under_construction;
2913 stack_arg_under_construction = 0;
2914 }
2915 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2916 if (flag_stack_usage_info)
2917 current_function_has_unbounded_dynamic_stack_size = 1;
2918 }
2919 else
2920 {
2921 /* Note that we must go through the motions of allocating an argument
2922 block even if the size is zero because we may be storing args
2923 in the area reserved for register arguments, which may be part of
2924 the stack frame. */
2925
2926 int needed = adjusted_args_size.constant;
2927
2928 /* Store the maximum argument space used. It will be pushed by
2929 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2930 checking). */
2931
2932 if (needed > crtl->outgoing_args_size)
2933 crtl->outgoing_args_size = needed;
2934
2935 if (must_preallocate)
2936 {
2937 if (ACCUMULATE_OUTGOING_ARGS)
2938 {
2939 /* Since the stack pointer will never be pushed, it is
2940 possible for the evaluation of a parm to clobber
2941 something we have already written to the stack.
2942 Since most function calls on RISC machines do not use
2943 the stack, this is uncommon, but must work correctly.
2944
2945 Therefore, we save any area of the stack that was already
2946 written and that we are using. Here we set up to do this
2947 by making a new stack usage map from the old one. The
2948 actual save will be done by store_one_arg.
2949
2950 Another approach might be to try to reorder the argument
2951 evaluations to avoid this conflicting stack usage. */
2952
2953 /* Since we will be writing into the entire argument area,
2954 the map must be allocated for its entire size, not just
2955 the part that is the responsibility of the caller. */
2956 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
2957 needed += reg_parm_stack_space;
2958
2959 if (ARGS_GROW_DOWNWARD)
2960 highest_outgoing_arg_in_use
2961 = MAX (initial_highest_arg_in_use, needed + 1);
2962 else
2963 highest_outgoing_arg_in_use
2964 = MAX (initial_highest_arg_in_use, needed);
2965
2966 free (stack_usage_map_buf);
2967 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
2968 stack_usage_map = stack_usage_map_buf;
2969
2970 if (initial_highest_arg_in_use)
2971 memcpy (stack_usage_map, initial_stack_usage_map,
2972 initial_highest_arg_in_use);
2973
2974 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2975 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2976 (highest_outgoing_arg_in_use
2977 - initial_highest_arg_in_use));
2978 needed = 0;
2979
2980 /* The address of the outgoing argument list must not be
2981 copied to a register here, because argblock would be left
2982 pointing to the wrong place after the call to
2983 allocate_dynamic_stack_space below. */
2984
2985 argblock = virtual_outgoing_args_rtx;
2986 }
2987 else
2988 {
2989 if (inhibit_defer_pop == 0)
2990 {
2991 /* Try to reuse some or all of the pending_stack_adjust
2992 to get this space. */
2993 needed
2994 = (combine_pending_stack_adjustment_and_call
2995 (unadjusted_args_size,
2996 &adjusted_args_size,
2997 preferred_unit_stack_boundary));
2998
2999 /* combine_pending_stack_adjustment_and_call computes
3000 an adjustment before the arguments are allocated.
3001 Account for them and see whether or not the stack
3002 needs to go up or down. */
3003 needed = unadjusted_args_size - needed;
3004
3005 if (needed < 0)
3006 {
3007 /* We're releasing stack space. */
3008 /* ??? We can avoid any adjustment at all if we're
3009 already aligned. FIXME. */
3010 pending_stack_adjust = -needed;
3011 do_pending_stack_adjust ();
3012 needed = 0;
3013 }
3014 else
3015 /* We need to allocate space. We'll do that in
3016 push_block below. */
3017 pending_stack_adjust = 0;
3018 }
3019
3020 /* Special case this because overhead of `push_block' in
3021 this case is non-trivial. */
3022 if (needed == 0)
3023 argblock = virtual_outgoing_args_rtx;
3024 else
3025 {
3026 argblock = push_block (GEN_INT (needed), 0, 0);
3027 if (ARGS_GROW_DOWNWARD)
3028 argblock = plus_constant (Pmode, argblock, needed);
3029 }
3030
3031 /* We only really need to call `copy_to_reg' in the case
3032 where push insns are going to be used to pass ARGBLOCK
3033 to a function call in ARGS. In that case, the stack
3034 pointer changes value from the allocation point to the
3035 call point, and hence the value of
3036 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
3037 as well always do it. */
3038 argblock = copy_to_reg (argblock);
3039 }
3040 }
3041 }
3042
3043 if (ACCUMULATE_OUTGOING_ARGS)
3044 {
3045 /* The save/restore code in store_one_arg handles all
3046 cases except one: a constructor call (including a C
3047 function returning a BLKmode struct) to initialize
3048 an argument. */
3049 if (stack_arg_under_construction)
3050 {
3051 rtx push_size
3052 = GEN_INT (adjusted_args_size.constant
3053 + (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype
3054 : TREE_TYPE (fndecl))) ? 0
3055 : reg_parm_stack_space));
3056 if (old_stack_level == 0)
3057 {
3058 emit_stack_save (SAVE_BLOCK, &old_stack_level);
3059 old_stack_pointer_delta = stack_pointer_delta;
3060 old_pending_adj = pending_stack_adjust;
3061 pending_stack_adjust = 0;
3062 /* stack_arg_under_construction says whether a stack
3063 arg is being constructed at the old stack level.
3064 Pushing the stack gets a clean outgoing argument
3065 block. */
3066 old_stack_arg_under_construction
3067 = stack_arg_under_construction;
3068 stack_arg_under_construction = 0;
3069 /* Make a new map for the new argument list. */
3070 free (stack_usage_map_buf);
3071 stack_usage_map_buf = XCNEWVEC (char, highest_outgoing_arg_in_use);
3072 stack_usage_map = stack_usage_map_buf;
3073 highest_outgoing_arg_in_use = 0;
3074 }
3075 /* We can pass TRUE as the 4th argument because we just
3076 saved the stack pointer and will restore it right after
3077 the call. */
3078 allocate_dynamic_stack_space (push_size, 0,
3079 BIGGEST_ALIGNMENT, true);
3080 }
3081
3082 /* If argument evaluation might modify the stack pointer,
3083 copy the address of the argument list to a register. */
3084 for (i = 0; i < num_actuals; i++)
3085 if (args[i].pass_on_stack)
3086 {
3087 argblock = copy_addr_to_reg (argblock);
3088 break;
3089 }
3090 }
3091
3092 compute_argument_addresses (args, argblock, num_actuals);
3093
3094 /* Stack is properly aligned, pops can't safely be deferred during
3095 the evaluation of the arguments. */
3096 NO_DEFER_POP;
3097
3098 /* Precompute all register parameters. It isn't safe to compute
3099 anything once we have started filling any specific hard regs.
3100 TLS symbols sometimes need a call to resolve. Precompute
3101 register parameters before any stack pointer manipulation
3102 to avoid unaligned stack in the called function. */
3103 precompute_register_parameters (num_actuals, args, &reg_parm_seen);
3104
3105 OK_DEFER_POP;
3106
3107 /* Perform stack alignment before the first push (the last arg). */
3108 if (argblock == 0
3109 && adjusted_args_size.constant > reg_parm_stack_space
3110 && adjusted_args_size.constant != unadjusted_args_size)
3111 {
3112 /* When the stack adjustment is pending, we get better code
3113 by combining the adjustments. */
3114 if (pending_stack_adjust
3115 && ! inhibit_defer_pop)
3116 {
3117 pending_stack_adjust
3118 = (combine_pending_stack_adjustment_and_call
3119 (unadjusted_args_size,
3120 &adjusted_args_size,
3121 preferred_unit_stack_boundary));
3122 do_pending_stack_adjust ();
3123 }
3124 else if (argblock == 0)
3125 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3126 - unadjusted_args_size));
3127 }
3128 /* Now that the stack is properly aligned, pops can't safely
3129 be deferred during the evaluation of the arguments. */
3130 NO_DEFER_POP;
3131
3132 /* Record the maximum pushed stack space size. We need to delay
3133 doing it this far to take into account the optimization done
3134 by combine_pending_stack_adjustment_and_call. */
3135 if (flag_stack_usage_info
3136 && !ACCUMULATE_OUTGOING_ARGS
3137 && pass
3138 && adjusted_args_size.var == 0)
3139 {
3140 int pushed = adjusted_args_size.constant + pending_stack_adjust;
3141 if (pushed > current_function_pushed_stack_size)
3142 current_function_pushed_stack_size = pushed;
3143 }
3144
3145 funexp = rtx_for_function_call (fndecl, addr);
3146
3147 if (CALL_EXPR_STATIC_CHAIN (exp))
3148 static_chain_value = expand_normal (CALL_EXPR_STATIC_CHAIN (exp));
3149 else
3150 static_chain_value = 0;
3151
3152 #ifdef REG_PARM_STACK_SPACE
3153 /* Save the fixed argument area if it's part of the caller's frame and
3154 is clobbered by argument setup for this call. */
3155 if (ACCUMULATE_OUTGOING_ARGS && pass)
3156 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3157 &low_to_save, &high_to_save);
3158 #endif
3159
3160 /* Now store (and compute if necessary) all non-register parms.
3161 These come before register parms, since they can require block-moves,
3162 which could clobber the registers used for register parms.
3163 Parms which have partial registers are not stored here,
3164 but we do preallocate space here if they want that. */
3165
3166 for (i = 0; i < num_actuals; i++)
3167 {
3168 /* Delay bounds until all other args are stored. */
3169 if (POINTER_BOUNDS_P (args[i].tree_value))
3170 continue;
3171 else if (args[i].reg == 0 || args[i].pass_on_stack)
3172 {
3173 rtx_insn *before_arg = get_last_insn ();
3174
3175 /* We don't allow passing huge (> 2^30 B) arguments
3176 by value. It would cause an overflow later on. */
3177 if (adjusted_args_size.constant
3178 >= (1 << (HOST_BITS_PER_INT - 2)))
3179 {
3180 sorry ("passing too large argument on stack");
3181 continue;
3182 }
3183
3184 if (store_one_arg (&args[i], argblock, flags,
3185 adjusted_args_size.var != 0,
3186 reg_parm_stack_space)
3187 || (pass == 0
3188 && check_sibcall_argument_overlap (before_arg,
3189 &args[i], 1)))
3190 sibcall_failure = 1;
3191 }
3192
3193 if (args[i].stack)
3194 call_fusage
3195 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
3196 gen_rtx_USE (VOIDmode, args[i].stack),
3197 call_fusage);
3198 }
3199
3200 /* If we have a parm that is passed in registers but not in memory
3201 and whose alignment does not permit a direct copy into registers,
3202 make a group of pseudos that correspond to each register that we
3203 will later fill. */
3204 if (STRICT_ALIGNMENT)
3205 store_unaligned_arguments_into_pseudos (args, num_actuals);
3206
3207 /* Now store any partially-in-registers parm.
3208 This is the last place a block-move can happen. */
3209 if (reg_parm_seen)
3210 for (i = 0; i < num_actuals; i++)
3211 if (args[i].partial != 0 && ! args[i].pass_on_stack)
3212 {
3213 rtx_insn *before_arg = get_last_insn ();
3214
3215 /* On targets with weird calling conventions (e.g. PA) it's
3216 hard to ensure that all cases of argument overlap between
3217 stack and registers work. Play it safe and bail out. */
3218 if (ARGS_GROW_DOWNWARD && !STACK_GROWS_DOWNWARD)
3219 {
3220 sibcall_failure = 1;
3221 break;
3222 }
3223
3224 if (store_one_arg (&args[i], argblock, flags,
3225 adjusted_args_size.var != 0,
3226 reg_parm_stack_space)
3227 || (pass == 0
3228 && check_sibcall_argument_overlap (before_arg,
3229 &args[i], 1)))
3230 sibcall_failure = 1;
3231 }
3232
3233 bool any_regs = false;
3234 for (i = 0; i < num_actuals; i++)
3235 if (args[i].reg != NULL_RTX)
3236 {
3237 any_regs = true;
3238 targetm.calls.call_args (args[i].reg, funtype);
3239 }
3240 if (!any_regs)
3241 targetm.calls.call_args (pc_rtx, funtype);
3242
3243 /* Figure out the register where the value, if any, will come back. */
3244 valreg = 0;
3245 valbnd = 0;
3246 if (TYPE_MODE (rettype) != VOIDmode
3247 && ! structure_value_addr)
3248 {
3249 if (pcc_struct_value)
3250 {
3251 valreg = hard_function_value (build_pointer_type (rettype),
3252 fndecl, NULL, (pass == 0));
3253 if (CALL_WITH_BOUNDS_P (exp))
3254 valbnd = targetm.calls.
3255 chkp_function_value_bounds (build_pointer_type (rettype),
3256 fndecl, (pass == 0));
3257 }
3258 else
3259 {
3260 valreg = hard_function_value (rettype, fndecl, fntype,
3261 (pass == 0));
3262 if (CALL_WITH_BOUNDS_P (exp))
3263 valbnd = targetm.calls.chkp_function_value_bounds (rettype,
3264 fndecl,
3265 (pass == 0));
3266 }
3267
3268 /* If VALREG is a PARALLEL whose first member has a zero
3269 offset, use that. This is for targets such as m68k that
3270 return the same value in multiple places. */
3271 if (GET_CODE (valreg) == PARALLEL)
3272 {
3273 rtx elem = XVECEXP (valreg, 0, 0);
3274 rtx where = XEXP (elem, 0);
3275 rtx offset = XEXP (elem, 1);
3276 if (offset == const0_rtx
3277 && GET_MODE (where) == GET_MODE (valreg))
3278 valreg = where;
3279 }
3280 }
3281
3282 /* Store all bounds not passed in registers. */
3283 for (i = 0; i < num_actuals; i++)
3284 {
3285 if (POINTER_BOUNDS_P (args[i].tree_value)
3286 && !args[i].reg)
3287 store_bounds (&args[i],
3288 args[i].pointer_arg == -1
3289 ? NULL
3290 : &args[args[i].pointer_arg]);
3291 }
3292
3293 /* If register arguments require space on the stack and stack space
3294 was not preallocated, allocate stack space here for arguments
3295 passed in registers. */
3296 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
3297 && !ACCUMULATE_OUTGOING_ARGS
3298 && must_preallocate == 0 && reg_parm_stack_space > 0)
3299 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3300
3301 /* Pass the function the address in which to return a
3302 structure value. */
3303 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3304 {
3305 structure_value_addr
3306 = convert_memory_address (Pmode, structure_value_addr);
3307 emit_move_insn (struct_value,
3308 force_reg (Pmode,
3309 force_operand (structure_value_addr,
3310 NULL_RTX)));
3311
3312 if (REG_P (struct_value))
3313 use_reg (&call_fusage, struct_value);
3314 }
3315
3316 after_args = get_last_insn ();
3317 funexp = prepare_call_address (fndecl ? fndecl : fntype, funexp,
3318 static_chain_value, &call_fusage,
3319 reg_parm_seen, pass == 0);
3320
3321 load_register_parameters (args, num_actuals, &call_fusage, flags,
3322 pass == 0, &sibcall_failure);
3323
3324 /* Save a pointer to the last insn before the call, so that we can
3325 later safely search backwards to find the CALL_INSN. */
3326 before_call = get_last_insn ();
3327
3328 /* Set up next argument register. For sibling calls on machines
3329 with register windows this should be the incoming register. */
3330 if (pass == 0)
3331 next_arg_reg = targetm.calls.function_incoming_arg (args_so_far,
3332 VOIDmode,
3333 void_type_node,
3334 true);
3335 else
3336 next_arg_reg = targetm.calls.function_arg (args_so_far,
3337 VOIDmode, void_type_node,
3338 true);
3339
3340 if (pass == 1 && (return_flags & ERF_RETURNS_ARG))
3341 {
3342 int arg_nr = return_flags & ERF_RETURN_ARG_MASK;
3343 arg_nr = num_actuals - arg_nr - 1;
3344 if (arg_nr >= 0
3345 && arg_nr < num_actuals
3346 && args[arg_nr].reg
3347 && valreg
3348 && REG_P (valreg)
3349 && GET_MODE (args[arg_nr].reg) == GET_MODE (valreg))
3350 call_fusage
3351 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[arg_nr].tree_value)),
3352 gen_rtx_SET (valreg, args[arg_nr].reg),
3353 call_fusage);
3354 }
3355 /* All arguments and registers used for the call must be set up by
3356 now! */
3357
3358 /* Stack must be properly aligned now. */
3359 gcc_assert (!pass
3360 || !(stack_pointer_delta % preferred_unit_stack_boundary));
3361
3362 /* Generate the actual call instruction. */
3363 emit_call_1 (funexp, exp, fndecl, funtype, unadjusted_args_size,
3364 adjusted_args_size.constant, struct_value_size,
3365 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3366 flags, args_so_far);
3367
3368 if (flag_ipa_ra)
3369 {
3370 rtx_call_insn *last;
3371 rtx datum = NULL_RTX;
3372 if (fndecl != NULL_TREE)
3373 {
3374 datum = XEXP (DECL_RTL (fndecl), 0);
3375 gcc_assert (datum != NULL_RTX
3376 && GET_CODE (datum) == SYMBOL_REF);
3377 }
3378 last = last_call_insn ();
3379 add_reg_note (last, REG_CALL_DECL, datum);
3380 }
3381
3382 /* If the call setup or the call itself overlaps with anything
3383 of the argument setup we probably clobbered our call address.
3384 In that case we can't do sibcalls. */
3385 if (pass == 0
3386 && check_sibcall_argument_overlap (after_args, 0, 0))
3387 sibcall_failure = 1;
3388
3389 /* If a non-BLKmode value is returned at the most significant end
3390 of a register, shift the register right by the appropriate amount
3391 and update VALREG accordingly. BLKmode values are handled by the
3392 group load/store machinery below. */
3393 if (!structure_value_addr
3394 && !pcc_struct_value
3395 && TYPE_MODE (rettype) != VOIDmode
3396 && TYPE_MODE (rettype) != BLKmode
3397 && REG_P (valreg)
3398 && targetm.calls.return_in_msb (rettype))
3399 {
3400 if (shift_return_value (TYPE_MODE (rettype), false, valreg))
3401 sibcall_failure = 1;
3402 valreg = gen_rtx_REG (TYPE_MODE (rettype), REGNO (valreg));
3403 }
3404
3405 if (pass && (flags & ECF_MALLOC))
3406 {
3407 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3408 rtx_insn *last, *insns;
3409
3410 /* The return value from a malloc-like function is a pointer. */
3411 if (TREE_CODE (rettype) == POINTER_TYPE)
3412 mark_reg_pointer (temp, MALLOC_ABI_ALIGNMENT);
3413
3414 emit_move_insn (temp, valreg);
3415
3416 /* The return value from a malloc-like function can not alias
3417 anything else. */
3418 last = get_last_insn ();
3419 add_reg_note (last, REG_NOALIAS, temp);
3420
3421 /* Write out the sequence. */
3422 insns = get_insns ();
3423 end_sequence ();
3424 emit_insn (insns);
3425 valreg = temp;
3426 }
3427
3428 /* For calls to `setjmp', etc., inform
3429 function.c:setjmp_warnings that it should complain if
3430 nonvolatile values are live. For functions that cannot
3431 return, inform flow that control does not fall through. */
3432
3433 if ((flags & ECF_NORETURN) || pass == 0)
3434 {
3435 /* The barrier must be emitted
3436 immediately after the CALL_INSN. Some ports emit more
3437 than just a CALL_INSN above, so we must search for it here. */
3438
3439 rtx_insn *last = get_last_insn ();
3440 while (!CALL_P (last))
3441 {
3442 last = PREV_INSN (last);
3443 /* There was no CALL_INSN? */
3444 gcc_assert (last != before_call);
3445 }
3446
3447 emit_barrier_after (last);
3448
3449 /* Stack adjustments after a noreturn call are dead code.
3450 However when NO_DEFER_POP is in effect, we must preserve
3451 stack_pointer_delta. */
3452 if (inhibit_defer_pop == 0)
3453 {
3454 stack_pointer_delta = old_stack_allocated;
3455 pending_stack_adjust = 0;
3456 }
3457 }
3458
3459 /* If value type not void, return an rtx for the value. */
3460
3461 if (TYPE_MODE (rettype) == VOIDmode
3462 || ignore)
3463 target = const0_rtx;
3464 else if (structure_value_addr)
3465 {
3466 if (target == 0 || !MEM_P (target))
3467 {
3468 target
3469 = gen_rtx_MEM (TYPE_MODE (rettype),
3470 memory_address (TYPE_MODE (rettype),
3471 structure_value_addr));
3472 set_mem_attributes (target, rettype, 1);
3473 }
3474 }
3475 else if (pcc_struct_value)
3476 {
3477 /* This is the special C++ case where we need to
3478 know what the true target was. We take care to
3479 never use this value more than once in one expression. */
3480 target = gen_rtx_MEM (TYPE_MODE (rettype),
3481 copy_to_reg (valreg));
3482 set_mem_attributes (target, rettype, 1);
3483 }
3484 /* Handle calls that return values in multiple non-contiguous locations.
3485 The Irix 6 ABI has examples of this. */
3486 else if (GET_CODE (valreg) == PARALLEL)
3487 {
3488 if (target == 0)
3489 target = emit_group_move_into_temps (valreg);
3490 else if (rtx_equal_p (target, valreg))
3491 ;
3492 else if (GET_CODE (target) == PARALLEL)
3493 /* Handle the result of a emit_group_move_into_temps
3494 call in the previous pass. */
3495 emit_group_move (target, valreg);
3496 else
3497 emit_group_store (target, valreg, rettype,
3498 int_size_in_bytes (rettype));
3499 }
3500 else if (target
3501 && GET_MODE (target) == TYPE_MODE (rettype)
3502 && GET_MODE (target) == GET_MODE (valreg))
3503 {
3504 bool may_overlap = false;
3505
3506 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
3507 reg to a plain register. */
3508 if (!REG_P (target) || HARD_REGISTER_P (target))
3509 valreg = avoid_likely_spilled_reg (valreg);
3510
3511 /* If TARGET is a MEM in the argument area, and we have
3512 saved part of the argument area, then we can't store
3513 directly into TARGET as it may get overwritten when we
3514 restore the argument save area below. Don't work too
3515 hard though and simply force TARGET to a register if it
3516 is a MEM; the optimizer is quite likely to sort it out. */
3517 if (ACCUMULATE_OUTGOING_ARGS && pass && MEM_P (target))
3518 for (i = 0; i < num_actuals; i++)
3519 if (args[i].save_area)
3520 {
3521 may_overlap = true;
3522 break;
3523 }
3524
3525 if (may_overlap)
3526 target = copy_to_reg (valreg);
3527 else
3528 {
3529 /* TARGET and VALREG cannot be equal at this point
3530 because the latter would not have
3531 REG_FUNCTION_VALUE_P true, while the former would if
3532 it were referring to the same register.
3533
3534 If they refer to the same register, this move will be
3535 a no-op, except when function inlining is being
3536 done. */
3537 emit_move_insn (target, valreg);
3538
3539 /* If we are setting a MEM, this code must be executed.
3540 Since it is emitted after the call insn, sibcall
3541 optimization cannot be performed in that case. */
3542 if (MEM_P (target))
3543 sibcall_failure = 1;
3544 }
3545 }
3546 else
3547 target = copy_to_reg (avoid_likely_spilled_reg (valreg));
3548
3549 /* If we promoted this return value, make the proper SUBREG.
3550 TARGET might be const0_rtx here, so be careful. */
3551 if (REG_P (target)
3552 && TYPE_MODE (rettype) != BLKmode
3553 && GET_MODE (target) != TYPE_MODE (rettype))
3554 {
3555 tree type = rettype;
3556 int unsignedp = TYPE_UNSIGNED (type);
3557 int offset = 0;
3558 machine_mode pmode;
3559
3560 /* Ensure we promote as expected, and get the new unsignedness. */
3561 pmode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
3562 funtype, 1);
3563 gcc_assert (GET_MODE (target) == pmode);
3564
3565 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3566 && (GET_MODE_SIZE (GET_MODE (target))
3567 > GET_MODE_SIZE (TYPE_MODE (type))))
3568 {
3569 offset = GET_MODE_SIZE (GET_MODE (target))
3570 - GET_MODE_SIZE (TYPE_MODE (type));
3571 if (! BYTES_BIG_ENDIAN)
3572 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3573 else if (! WORDS_BIG_ENDIAN)
3574 offset %= UNITS_PER_WORD;
3575 }
3576
3577 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3578 SUBREG_PROMOTED_VAR_P (target) = 1;
3579 SUBREG_PROMOTED_SET (target, unsignedp);
3580 }
3581
3582 /* If size of args is variable or this was a constructor call for a stack
3583 argument, restore saved stack-pointer value. */
3584
3585 if (old_stack_level)
3586 {
3587 rtx_insn *prev = get_last_insn ();
3588
3589 emit_stack_restore (SAVE_BLOCK, old_stack_level);
3590 stack_pointer_delta = old_stack_pointer_delta;
3591
3592 fixup_args_size_notes (prev, get_last_insn (), stack_pointer_delta);
3593
3594 pending_stack_adjust = old_pending_adj;
3595 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
3596 stack_arg_under_construction = old_stack_arg_under_construction;
3597 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3598 stack_usage_map = initial_stack_usage_map;
3599 sibcall_failure = 1;
3600 }
3601 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3602 {
3603 #ifdef REG_PARM_STACK_SPACE
3604 if (save_area)
3605 restore_fixed_argument_area (save_area, argblock,
3606 high_to_save, low_to_save);
3607 #endif
3608
3609 /* If we saved any argument areas, restore them. */
3610 for (i = 0; i < num_actuals; i++)
3611 if (args[i].save_area)
3612 {
3613 machine_mode save_mode = GET_MODE (args[i].save_area);
3614 rtx stack_area
3615 = gen_rtx_MEM (save_mode,
3616 memory_address (save_mode,
3617 XEXP (args[i].stack_slot, 0)));
3618
3619 if (save_mode != BLKmode)
3620 emit_move_insn (stack_area, args[i].save_area);
3621 else
3622 emit_block_move (stack_area, args[i].save_area,
3623 GEN_INT (args[i].locate.size.constant),
3624 BLOCK_OP_CALL_PARM);
3625 }
3626
3627 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3628 stack_usage_map = initial_stack_usage_map;
3629 }
3630
3631 /* If this was alloca, record the new stack level. */
3632 if (flags & ECF_MAY_BE_ALLOCA)
3633 record_new_stack_level ();
3634
3635 /* Free up storage we no longer need. */
3636 for (i = 0; i < num_actuals; ++i)
3637 free (args[i].aligned_regs);
3638
3639 targetm.calls.end_call_args ();
3640
3641 insns = get_insns ();
3642 end_sequence ();
3643
3644 if (pass == 0)
3645 {
3646 tail_call_insns = insns;
3647
3648 /* Restore the pending stack adjustment now that we have
3649 finished generating the sibling call sequence. */
3650
3651 restore_pending_stack_adjust (&save);
3652
3653 /* Prepare arg structure for next iteration. */
3654 for (i = 0; i < num_actuals; i++)
3655 {
3656 args[i].value = 0;
3657 args[i].aligned_regs = 0;
3658 args[i].stack = 0;
3659 }
3660
3661 sbitmap_free (stored_args_map);
3662 internal_arg_pointer_exp_state.scan_start = NULL;
3663 internal_arg_pointer_exp_state.cache.release ();
3664 }
3665 else
3666 {
3667 normal_call_insns = insns;
3668
3669 /* Verify that we've deallocated all the stack we used. */
3670 gcc_assert ((flags & ECF_NORETURN)
3671 || (old_stack_allocated
3672 == stack_pointer_delta - pending_stack_adjust));
3673 }
3674
3675 /* If something prevents making this a sibling call,
3676 zero out the sequence. */
3677 if (sibcall_failure)
3678 tail_call_insns = NULL;
3679 else
3680 break;
3681 }
3682
3683 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
3684 arguments too, as argument area is now clobbered by the call. */
3685 if (tail_call_insns)
3686 {
3687 emit_insn (tail_call_insns);
3688 crtl->tail_call_emit = true;
3689 }
3690 else
3691 emit_insn (normal_call_insns);
3692
3693 currently_expanding_call--;
3694
3695 free (stack_usage_map_buf);
3696
3697 /* Join result with returned bounds so caller may use them if needed. */
3698 target = chkp_join_splitted_slot (target, valbnd);
3699
3700 return target;
3701 }
3702
3703 /* A sibling call sequence invalidates any REG_EQUIV notes made for
3704 this function's incoming arguments.
3705
3706 At the start of RTL generation we know the only REG_EQUIV notes
3707 in the rtl chain are those for incoming arguments, so we can look
3708 for REG_EQUIV notes between the start of the function and the
3709 NOTE_INSN_FUNCTION_BEG.
3710
3711 This is (slight) overkill. We could keep track of the highest
3712 argument we clobber and be more selective in removing notes, but it
3713 does not seem to be worth the effort. */
3714
3715 void
3716 fixup_tail_calls (void)
3717 {
3718 rtx_insn *insn;
3719
3720 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3721 {
3722 rtx note;
3723
3724 /* There are never REG_EQUIV notes for the incoming arguments
3725 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
3726 if (NOTE_P (insn)
3727 && NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG)
3728 break;
3729
3730 note = find_reg_note (insn, REG_EQUIV, 0);
3731 if (note)
3732 remove_note (insn, note);
3733 note = find_reg_note (insn, REG_EQUIV, 0);
3734 gcc_assert (!note);
3735 }
3736 }
3737
3738 /* Traverse a list of TYPES and expand all complex types into their
3739 components. */
3740 static tree
3741 split_complex_types (tree types)
3742 {
3743 tree p;
3744
3745 /* Before allocating memory, check for the common case of no complex. */
3746 for (p = types; p; p = TREE_CHAIN (p))
3747 {
3748 tree type = TREE_VALUE (p);
3749 if (TREE_CODE (type) == COMPLEX_TYPE
3750 && targetm.calls.split_complex_arg (type))
3751 goto found;
3752 }
3753 return types;
3754
3755 found:
3756 types = copy_list (types);
3757
3758 for (p = types; p; p = TREE_CHAIN (p))
3759 {
3760 tree complex_type = TREE_VALUE (p);
3761
3762 if (TREE_CODE (complex_type) == COMPLEX_TYPE
3763 && targetm.calls.split_complex_arg (complex_type))
3764 {
3765 tree next, imag;
3766
3767 /* Rewrite complex type with component type. */
3768 TREE_VALUE (p) = TREE_TYPE (complex_type);
3769 next = TREE_CHAIN (p);
3770
3771 /* Add another component type for the imaginary part. */
3772 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
3773 TREE_CHAIN (p) = imag;
3774 TREE_CHAIN (imag) = next;
3775
3776 /* Skip the newly created node. */
3777 p = TREE_CHAIN (p);
3778 }
3779 }
3780
3781 return types;
3782 }
3783 \f
3784 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3785 The RETVAL parameter specifies whether return value needs to be saved, other
3786 parameters are documented in the emit_library_call function below. */
3787
3788 static rtx
3789 emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
3790 enum libcall_type fn_type,
3791 machine_mode outmode, int nargs, va_list p)
3792 {
3793 /* Total size in bytes of all the stack-parms scanned so far. */
3794 struct args_size args_size;
3795 /* Size of arguments before any adjustments (such as rounding). */
3796 struct args_size original_args_size;
3797 int argnum;
3798 rtx fun;
3799 /* Todo, choose the correct decl type of orgfun. Sadly this information
3800 isn't present here, so we default to native calling abi here. */
3801 tree fndecl ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
3802 tree fntype ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
3803 int count;
3804 rtx argblock = 0;
3805 CUMULATIVE_ARGS args_so_far_v;
3806 cumulative_args_t args_so_far;
3807 struct arg
3808 {
3809 rtx value;
3810 machine_mode mode;
3811 rtx reg;
3812 int partial;
3813 struct locate_and_pad_arg_data locate;
3814 rtx save_area;
3815 };
3816 struct arg *argvec;
3817 int old_inhibit_defer_pop = inhibit_defer_pop;
3818 rtx call_fusage = 0;
3819 rtx mem_value = 0;
3820 rtx valreg;
3821 int pcc_struct_value = 0;
3822 int struct_value_size = 0;
3823 int flags;
3824 int reg_parm_stack_space = 0;
3825 int needed;
3826 rtx_insn *before_call;
3827 bool have_push_fusage;
3828 tree tfom; /* type_for_mode (outmode, 0) */
3829
3830 #ifdef REG_PARM_STACK_SPACE
3831 /* Define the boundary of the register parm stack space that needs to be
3832 save, if any. */
3833 int low_to_save = 0, high_to_save = 0;
3834 rtx save_area = 0; /* Place that it is saved. */
3835 #endif
3836
3837 /* Size of the stack reserved for parameter registers. */
3838 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3839 char *initial_stack_usage_map = stack_usage_map;
3840 char *stack_usage_map_buf = NULL;
3841
3842 rtx struct_value = targetm.calls.struct_value_rtx (0, 0);
3843
3844 #ifdef REG_PARM_STACK_SPACE
3845 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3846 #endif
3847
3848 /* By default, library functions can not throw. */
3849 flags = ECF_NOTHROW;
3850
3851 switch (fn_type)
3852 {
3853 case LCT_NORMAL:
3854 break;
3855 case LCT_CONST:
3856 flags |= ECF_CONST;
3857 break;
3858 case LCT_PURE:
3859 flags |= ECF_PURE;
3860 break;
3861 case LCT_NORETURN:
3862 flags |= ECF_NORETURN;
3863 break;
3864 case LCT_THROW:
3865 flags = ECF_NORETURN;
3866 break;
3867 case LCT_RETURNS_TWICE:
3868 flags = ECF_RETURNS_TWICE;
3869 break;
3870 }
3871 fun = orgfun;
3872
3873 /* Ensure current function's preferred stack boundary is at least
3874 what we need. */
3875 if (crtl->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3876 crtl->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3877
3878 /* If this kind of value comes back in memory,
3879 decide where in memory it should come back. */
3880 if (outmode != VOIDmode)
3881 {
3882 tfom = lang_hooks.types.type_for_mode (outmode, 0);
3883 if (aggregate_value_p (tfom, 0))
3884 {
3885 #ifdef PCC_STATIC_STRUCT_RETURN
3886 rtx pointer_reg
3887 = hard_function_value (build_pointer_type (tfom), 0, 0, 0);
3888 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3889 pcc_struct_value = 1;
3890 if (value == 0)
3891 value = gen_reg_rtx (outmode);
3892 #else /* not PCC_STATIC_STRUCT_RETURN */
3893 struct_value_size = GET_MODE_SIZE (outmode);
3894 if (value != 0 && MEM_P (value))
3895 mem_value = value;
3896 else
3897 mem_value = assign_temp (tfom, 1, 1);
3898 #endif
3899 /* This call returns a big structure. */
3900 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
3901 }
3902 }
3903 else
3904 tfom = void_type_node;
3905
3906 /* ??? Unfinished: must pass the memory address as an argument. */
3907
3908 /* Copy all the libcall-arguments out of the varargs data
3909 and into a vector ARGVEC.
3910
3911 Compute how to pass each argument. We only support a very small subset
3912 of the full argument passing conventions to limit complexity here since
3913 library functions shouldn't have many args. */
3914
3915 argvec = XALLOCAVEC (struct arg, nargs + 1);
3916 memset (argvec, 0, (nargs + 1) * sizeof (struct arg));
3917
3918 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3919 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v, outmode, fun);
3920 #else
3921 INIT_CUMULATIVE_ARGS (args_so_far_v, NULL_TREE, fun, 0, nargs);
3922 #endif
3923 args_so_far = pack_cumulative_args (&args_so_far_v);
3924
3925 args_size.constant = 0;
3926 args_size.var = 0;
3927
3928 count = 0;
3929
3930 push_temp_slots ();
3931
3932 /* If there's a structure value address to be passed,
3933 either pass it in the special place, or pass it as an extra argument. */
3934 if (mem_value && struct_value == 0 && ! pcc_struct_value)
3935 {
3936 rtx addr = XEXP (mem_value, 0);
3937
3938 nargs++;
3939
3940 /* Make sure it is a reasonable operand for a move or push insn. */
3941 if (!REG_P (addr) && !MEM_P (addr)
3942 && !(CONSTANT_P (addr)
3943 && targetm.legitimate_constant_p (Pmode, addr)))
3944 addr = force_operand (addr, NULL_RTX);
3945
3946 argvec[count].value = addr;
3947 argvec[count].mode = Pmode;
3948 argvec[count].partial = 0;
3949
3950 argvec[count].reg = targetm.calls.function_arg (args_so_far,
3951 Pmode, NULL_TREE, true);
3952 gcc_assert (targetm.calls.arg_partial_bytes (args_so_far, Pmode,
3953 NULL_TREE, 1) == 0);
3954
3955 locate_and_pad_parm (Pmode, NULL_TREE,
3956 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3957 1,
3958 #else
3959 argvec[count].reg != 0,
3960 #endif
3961 reg_parm_stack_space, 0,
3962 NULL_TREE, &args_size, &argvec[count].locate);
3963
3964 if (argvec[count].reg == 0 || argvec[count].partial != 0
3965 || reg_parm_stack_space > 0)
3966 args_size.constant += argvec[count].locate.size.constant;
3967
3968 targetm.calls.function_arg_advance (args_so_far, Pmode, (tree) 0, true);
3969
3970 count++;
3971 }
3972
3973 for (; count < nargs; count++)
3974 {
3975 rtx val = va_arg (p, rtx);
3976 machine_mode mode = (machine_mode) va_arg (p, int);
3977 int unsigned_p = 0;
3978
3979 /* We cannot convert the arg value to the mode the library wants here;
3980 must do it earlier where we know the signedness of the arg. */
3981 gcc_assert (mode != BLKmode
3982 && (GET_MODE (val) == mode || GET_MODE (val) == VOIDmode));
3983
3984 /* Make sure it is a reasonable operand for a move or push insn. */
3985 if (!REG_P (val) && !MEM_P (val)
3986 && !(CONSTANT_P (val) && targetm.legitimate_constant_p (mode, val)))
3987 val = force_operand (val, NULL_RTX);
3988
3989 if (pass_by_reference (&args_so_far_v, mode, NULL_TREE, 1))
3990 {
3991 rtx slot;
3992 int must_copy
3993 = !reference_callee_copied (&args_so_far_v, mode, NULL_TREE, 1);
3994
3995 /* If this was a CONST function, it is now PURE since it now
3996 reads memory. */
3997 if (flags & ECF_CONST)
3998 {
3999 flags &= ~ECF_CONST;
4000 flags |= ECF_PURE;
4001 }
4002
4003 if (MEM_P (val) && !must_copy)
4004 {
4005 tree val_expr = MEM_EXPR (val);
4006 if (val_expr)
4007 mark_addressable (val_expr);
4008 slot = val;
4009 }
4010 else
4011 {
4012 slot = assign_temp (lang_hooks.types.type_for_mode (mode, 0),
4013 1, 1);
4014 emit_move_insn (slot, val);
4015 }
4016
4017 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4018 gen_rtx_USE (VOIDmode, slot),
4019 call_fusage);
4020 if (must_copy)
4021 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4022 gen_rtx_CLOBBER (VOIDmode,
4023 slot),
4024 call_fusage);
4025
4026 mode = Pmode;
4027 val = force_operand (XEXP (slot, 0), NULL_RTX);
4028 }
4029
4030 mode = promote_function_mode (NULL_TREE, mode, &unsigned_p, NULL_TREE, 0);
4031 argvec[count].mode = mode;
4032 argvec[count].value = convert_modes (mode, GET_MODE (val), val, unsigned_p);
4033 argvec[count].reg = targetm.calls.function_arg (args_so_far, mode,
4034 NULL_TREE, true);
4035
4036 argvec[count].partial
4037 = targetm.calls.arg_partial_bytes (args_so_far, mode, NULL_TREE, 1);
4038
4039 if (argvec[count].reg == 0
4040 || argvec[count].partial != 0
4041 || reg_parm_stack_space > 0)
4042 {
4043 locate_and_pad_parm (mode, NULL_TREE,
4044 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4045 1,
4046 #else
4047 argvec[count].reg != 0,
4048 #endif
4049 reg_parm_stack_space, argvec[count].partial,
4050 NULL_TREE, &args_size, &argvec[count].locate);
4051 args_size.constant += argvec[count].locate.size.constant;
4052 gcc_assert (!argvec[count].locate.size.var);
4053 }
4054 #ifdef BLOCK_REG_PADDING
4055 else
4056 /* The argument is passed entirely in registers. See at which
4057 end it should be padded. */
4058 argvec[count].locate.where_pad =
4059 BLOCK_REG_PADDING (mode, NULL_TREE,
4060 GET_MODE_SIZE (mode) <= UNITS_PER_WORD);
4061 #endif
4062
4063 targetm.calls.function_arg_advance (args_so_far, mode, (tree) 0, true);
4064 }
4065
4066 /* If this machine requires an external definition for library
4067 functions, write one out. */
4068 assemble_external_libcall (fun);
4069
4070 original_args_size = args_size;
4071 args_size.constant = (((args_size.constant
4072 + stack_pointer_delta
4073 + STACK_BYTES - 1)
4074 / STACK_BYTES
4075 * STACK_BYTES)
4076 - stack_pointer_delta);
4077
4078 args_size.constant = MAX (args_size.constant,
4079 reg_parm_stack_space);
4080
4081 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
4082 args_size.constant -= reg_parm_stack_space;
4083
4084 if (args_size.constant > crtl->outgoing_args_size)
4085 crtl->outgoing_args_size = args_size.constant;
4086
4087 if (flag_stack_usage_info && !ACCUMULATE_OUTGOING_ARGS)
4088 {
4089 int pushed = args_size.constant + pending_stack_adjust;
4090 if (pushed > current_function_pushed_stack_size)
4091 current_function_pushed_stack_size = pushed;
4092 }
4093
4094 if (ACCUMULATE_OUTGOING_ARGS)
4095 {
4096 /* Since the stack pointer will never be pushed, it is possible for
4097 the evaluation of a parm to clobber something we have already
4098 written to the stack. Since most function calls on RISC machines
4099 do not use the stack, this is uncommon, but must work correctly.
4100
4101 Therefore, we save any area of the stack that was already written
4102 and that we are using. Here we set up to do this by making a new
4103 stack usage map from the old one.
4104
4105 Another approach might be to try to reorder the argument
4106 evaluations to avoid this conflicting stack usage. */
4107
4108 needed = args_size.constant;
4109
4110 /* Since we will be writing into the entire argument area, the
4111 map must be allocated for its entire size, not just the part that
4112 is the responsibility of the caller. */
4113 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
4114 needed += reg_parm_stack_space;
4115
4116 if (ARGS_GROW_DOWNWARD)
4117 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
4118 needed + 1);
4119 else
4120 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use, needed);
4121
4122 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
4123 stack_usage_map = stack_usage_map_buf;
4124
4125 if (initial_highest_arg_in_use)
4126 memcpy (stack_usage_map, initial_stack_usage_map,
4127 initial_highest_arg_in_use);
4128
4129 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
4130 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
4131 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
4132 needed = 0;
4133
4134 /* We must be careful to use virtual regs before they're instantiated,
4135 and real regs afterwards. Loop optimization, for example, can create
4136 new libcalls after we've instantiated the virtual regs, and if we
4137 use virtuals anyway, they won't match the rtl patterns. */
4138
4139 if (virtuals_instantiated)
4140 argblock = plus_constant (Pmode, stack_pointer_rtx,
4141 STACK_POINTER_OFFSET);
4142 else
4143 argblock = virtual_outgoing_args_rtx;
4144 }
4145 else
4146 {
4147 if (!PUSH_ARGS)
4148 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
4149 }
4150
4151 /* We push args individually in reverse order, perform stack alignment
4152 before the first push (the last arg). */
4153 if (argblock == 0)
4154 anti_adjust_stack (GEN_INT (args_size.constant
4155 - original_args_size.constant));
4156
4157 argnum = nargs - 1;
4158
4159 #ifdef REG_PARM_STACK_SPACE
4160 if (ACCUMULATE_OUTGOING_ARGS)
4161 {
4162 /* The argument list is the property of the called routine and it
4163 may clobber it. If the fixed area has been used for previous
4164 parameters, we must save and restore it. */
4165 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
4166 &low_to_save, &high_to_save);
4167 }
4168 #endif
4169
4170 /* When expanding a normal call, args are stored in push order,
4171 which is the reverse of what we have here. */
4172 bool any_regs = false;
4173 for (int i = nargs; i-- > 0; )
4174 if (argvec[i].reg != NULL_RTX)
4175 {
4176 targetm.calls.call_args (argvec[i].reg, NULL_TREE);
4177 any_regs = true;
4178 }
4179 if (!any_regs)
4180 targetm.calls.call_args (pc_rtx, NULL_TREE);
4181
4182 /* Push the args that need to be pushed. */
4183
4184 have_push_fusage = false;
4185
4186 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4187 are to be pushed. */
4188 for (count = 0; count < nargs; count++, argnum--)
4189 {
4190 machine_mode mode = argvec[argnum].mode;
4191 rtx val = argvec[argnum].value;
4192 rtx reg = argvec[argnum].reg;
4193 int partial = argvec[argnum].partial;
4194 unsigned int parm_align = argvec[argnum].locate.boundary;
4195 int lower_bound = 0, upper_bound = 0, i;
4196
4197 if (! (reg != 0 && partial == 0))
4198 {
4199 rtx use;
4200
4201 if (ACCUMULATE_OUTGOING_ARGS)
4202 {
4203 /* If this is being stored into a pre-allocated, fixed-size,
4204 stack area, save any previous data at that location. */
4205
4206 if (ARGS_GROW_DOWNWARD)
4207 {
4208 /* stack_slot is negative, but we want to index stack_usage_map
4209 with positive values. */
4210 upper_bound = -argvec[argnum].locate.slot_offset.constant + 1;
4211 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
4212 }
4213 else
4214 {
4215 lower_bound = argvec[argnum].locate.slot_offset.constant;
4216 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
4217 }
4218
4219 i = lower_bound;
4220 /* Don't worry about things in the fixed argument area;
4221 it has already been saved. */
4222 if (i < reg_parm_stack_space)
4223 i = reg_parm_stack_space;
4224 while (i < upper_bound && stack_usage_map[i] == 0)
4225 i++;
4226
4227 if (i < upper_bound)
4228 {
4229 /* We need to make a save area. */
4230 unsigned int size
4231 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
4232 machine_mode save_mode
4233 = mode_for_size (size, MODE_INT, 1);
4234 rtx adr
4235 = plus_constant (Pmode, argblock,
4236 argvec[argnum].locate.offset.constant);
4237 rtx stack_area
4238 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
4239
4240 if (save_mode == BLKmode)
4241 {
4242 argvec[argnum].save_area
4243 = assign_stack_temp (BLKmode,
4244 argvec[argnum].locate.size.constant
4245 );
4246
4247 emit_block_move (validize_mem
4248 (copy_rtx (argvec[argnum].save_area)),
4249 stack_area,
4250 GEN_INT (argvec[argnum].locate.size.constant),
4251 BLOCK_OP_CALL_PARM);
4252 }
4253 else
4254 {
4255 argvec[argnum].save_area = gen_reg_rtx (save_mode);
4256
4257 emit_move_insn (argvec[argnum].save_area, stack_area);
4258 }
4259 }
4260 }
4261
4262 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, parm_align,
4263 partial, reg, 0, argblock,
4264 GEN_INT (argvec[argnum].locate.offset.constant),
4265 reg_parm_stack_space,
4266 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad), false);
4267
4268 /* Now mark the segment we just used. */
4269 if (ACCUMULATE_OUTGOING_ARGS)
4270 for (i = lower_bound; i < upper_bound; i++)
4271 stack_usage_map[i] = 1;
4272
4273 NO_DEFER_POP;
4274
4275 /* Indicate argument access so that alias.c knows that these
4276 values are live. */
4277 if (argblock)
4278 use = plus_constant (Pmode, argblock,
4279 argvec[argnum].locate.offset.constant);
4280 else if (have_push_fusage)
4281 continue;
4282 else
4283 {
4284 /* When arguments are pushed, trying to tell alias.c where
4285 exactly this argument is won't work, because the
4286 auto-increment causes confusion. So we merely indicate
4287 that we access something with a known mode somewhere on
4288 the stack. */
4289 use = gen_rtx_PLUS (Pmode, stack_pointer_rtx,
4290 gen_rtx_SCRATCH (Pmode));
4291 have_push_fusage = true;
4292 }
4293 use = gen_rtx_MEM (argvec[argnum].mode, use);
4294 use = gen_rtx_USE (VOIDmode, use);
4295 call_fusage = gen_rtx_EXPR_LIST (VOIDmode, use, call_fusage);
4296 }
4297 }
4298
4299 argnum = nargs - 1;
4300
4301 fun = prepare_call_address (NULL, fun, NULL, &call_fusage, 0, 0);
4302
4303 /* Now load any reg parms into their regs. */
4304
4305 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4306 are to be pushed. */
4307 for (count = 0; count < nargs; count++, argnum--)
4308 {
4309 machine_mode mode = argvec[argnum].mode;
4310 rtx val = argvec[argnum].value;
4311 rtx reg = argvec[argnum].reg;
4312 int partial = argvec[argnum].partial;
4313 #ifdef BLOCK_REG_PADDING
4314 int size = 0;
4315 #endif
4316
4317 /* Handle calls that pass values in multiple non-contiguous
4318 locations. The PA64 has examples of this for library calls. */
4319 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4320 emit_group_load (reg, val, NULL_TREE, GET_MODE_SIZE (mode));
4321 else if (reg != 0 && partial == 0)
4322 {
4323 emit_move_insn (reg, val);
4324 #ifdef BLOCK_REG_PADDING
4325 size = GET_MODE_SIZE (argvec[argnum].mode);
4326
4327 /* Copied from load_register_parameters. */
4328
4329 /* Handle case where we have a value that needs shifting
4330 up to the msb. eg. a QImode value and we're padding
4331 upward on a BYTES_BIG_ENDIAN machine. */
4332 if (size < UNITS_PER_WORD
4333 && (argvec[argnum].locate.where_pad
4334 == (BYTES_BIG_ENDIAN ? upward : downward)))
4335 {
4336 rtx x;
4337 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4338
4339 /* Assigning REG here rather than a temp makes CALL_FUSAGE
4340 report the whole reg as used. Strictly speaking, the
4341 call only uses SIZE bytes at the msb end, but it doesn't
4342 seem worth generating rtl to say that. */
4343 reg = gen_rtx_REG (word_mode, REGNO (reg));
4344 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
4345 if (x != reg)
4346 emit_move_insn (reg, x);
4347 }
4348 #endif
4349 }
4350
4351 NO_DEFER_POP;
4352 }
4353
4354 /* Any regs containing parms remain in use through the call. */
4355 for (count = 0; count < nargs; count++)
4356 {
4357 rtx reg = argvec[count].reg;
4358 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4359 use_group_regs (&call_fusage, reg);
4360 else if (reg != 0)
4361 {
4362 int partial = argvec[count].partial;
4363 if (partial)
4364 {
4365 int nregs;
4366 gcc_assert (partial % UNITS_PER_WORD == 0);
4367 nregs = partial / UNITS_PER_WORD;
4368 use_regs (&call_fusage, REGNO (reg), nregs);
4369 }
4370 else
4371 use_reg (&call_fusage, reg);
4372 }
4373 }
4374
4375 /* Pass the function the address in which to return a structure value. */
4376 if (mem_value != 0 && struct_value != 0 && ! pcc_struct_value)
4377 {
4378 emit_move_insn (struct_value,
4379 force_reg (Pmode,
4380 force_operand (XEXP (mem_value, 0),
4381 NULL_RTX)));
4382 if (REG_P (struct_value))
4383 use_reg (&call_fusage, struct_value);
4384 }
4385
4386 /* Don't allow popping to be deferred, since then
4387 cse'ing of library calls could delete a call and leave the pop. */
4388 NO_DEFER_POP;
4389 valreg = (mem_value == 0 && outmode != VOIDmode
4390 ? hard_libcall_value (outmode, orgfun) : NULL_RTX);
4391
4392 /* Stack must be properly aligned now. */
4393 gcc_assert (!(stack_pointer_delta
4394 & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1)));
4395
4396 before_call = get_last_insn ();
4397
4398 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4399 will set inhibit_defer_pop to that value. */
4400 /* The return type is needed to decide how many bytes the function pops.
4401 Signedness plays no role in that, so for simplicity, we pretend it's
4402 always signed. We also assume that the list of arguments passed has
4403 no impact, so we pretend it is unknown. */
4404
4405 emit_call_1 (fun, NULL,
4406 get_identifier (XSTR (orgfun, 0)),
4407 build_function_type (tfom, NULL_TREE),
4408 original_args_size.constant, args_size.constant,
4409 struct_value_size,
4410 targetm.calls.function_arg (args_so_far,
4411 VOIDmode, void_type_node, true),
4412 valreg,
4413 old_inhibit_defer_pop + 1, call_fusage, flags, args_so_far);
4414
4415 if (flag_ipa_ra)
4416 {
4417 rtx datum = orgfun;
4418 gcc_assert (GET_CODE (datum) == SYMBOL_REF);
4419 rtx_call_insn *last = last_call_insn ();
4420 add_reg_note (last, REG_CALL_DECL, datum);
4421 }
4422
4423 /* Right-shift returned value if necessary. */
4424 if (!pcc_struct_value
4425 && TYPE_MODE (tfom) != BLKmode
4426 && targetm.calls.return_in_msb (tfom))
4427 {
4428 shift_return_value (TYPE_MODE (tfom), false, valreg);
4429 valreg = gen_rtx_REG (TYPE_MODE (tfom), REGNO (valreg));
4430 }
4431
4432 targetm.calls.end_call_args ();
4433
4434 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
4435 that it should complain if nonvolatile values are live. For
4436 functions that cannot return, inform flow that control does not
4437 fall through. */
4438 if (flags & ECF_NORETURN)
4439 {
4440 /* The barrier note must be emitted
4441 immediately after the CALL_INSN. Some ports emit more than
4442 just a CALL_INSN above, so we must search for it here. */
4443 rtx_insn *last = get_last_insn ();
4444 while (!CALL_P (last))
4445 {
4446 last = PREV_INSN (last);
4447 /* There was no CALL_INSN? */
4448 gcc_assert (last != before_call);
4449 }
4450
4451 emit_barrier_after (last);
4452 }
4453
4454 /* Consider that "regular" libcalls, i.e. all of them except for LCT_THROW
4455 and LCT_RETURNS_TWICE, cannot perform non-local gotos. */
4456 if (flags & ECF_NOTHROW)
4457 {
4458 rtx_insn *last = get_last_insn ();
4459 while (!CALL_P (last))
4460 {
4461 last = PREV_INSN (last);
4462 /* There was no CALL_INSN? */
4463 gcc_assert (last != before_call);
4464 }
4465
4466 make_reg_eh_region_note_nothrow_nononlocal (last);
4467 }
4468
4469 /* Now restore inhibit_defer_pop to its actual original value. */
4470 OK_DEFER_POP;
4471
4472 pop_temp_slots ();
4473
4474 /* Copy the value to the right place. */
4475 if (outmode != VOIDmode && retval)
4476 {
4477 if (mem_value)
4478 {
4479 if (value == 0)
4480 value = mem_value;
4481 if (value != mem_value)
4482 emit_move_insn (value, mem_value);
4483 }
4484 else if (GET_CODE (valreg) == PARALLEL)
4485 {
4486 if (value == 0)
4487 value = gen_reg_rtx (outmode);
4488 emit_group_store (value, valreg, NULL_TREE, GET_MODE_SIZE (outmode));
4489 }
4490 else
4491 {
4492 /* Convert to the proper mode if a promotion has been active. */
4493 if (GET_MODE (valreg) != outmode)
4494 {
4495 int unsignedp = TYPE_UNSIGNED (tfom);
4496
4497 gcc_assert (promote_function_mode (tfom, outmode, &unsignedp,
4498 fndecl ? TREE_TYPE (fndecl) : fntype, 1)
4499 == GET_MODE (valreg));
4500 valreg = convert_modes (outmode, GET_MODE (valreg), valreg, 0);
4501 }
4502
4503 if (value != 0)
4504 emit_move_insn (value, valreg);
4505 else
4506 value = valreg;
4507 }
4508 }
4509
4510 if (ACCUMULATE_OUTGOING_ARGS)
4511 {
4512 #ifdef REG_PARM_STACK_SPACE
4513 if (save_area)
4514 restore_fixed_argument_area (save_area, argblock,
4515 high_to_save, low_to_save);
4516 #endif
4517
4518 /* If we saved any argument areas, restore them. */
4519 for (count = 0; count < nargs; count++)
4520 if (argvec[count].save_area)
4521 {
4522 machine_mode save_mode = GET_MODE (argvec[count].save_area);
4523 rtx adr = plus_constant (Pmode, argblock,
4524 argvec[count].locate.offset.constant);
4525 rtx stack_area = gen_rtx_MEM (save_mode,
4526 memory_address (save_mode, adr));
4527
4528 if (save_mode == BLKmode)
4529 emit_block_move (stack_area,
4530 validize_mem
4531 (copy_rtx (argvec[count].save_area)),
4532 GEN_INT (argvec[count].locate.size.constant),
4533 BLOCK_OP_CALL_PARM);
4534 else
4535 emit_move_insn (stack_area, argvec[count].save_area);
4536 }
4537
4538 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4539 stack_usage_map = initial_stack_usage_map;
4540 }
4541
4542 free (stack_usage_map_buf);
4543
4544 return value;
4545
4546 }
4547 \f
4548 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4549 (emitting the queue unless NO_QUEUE is nonzero),
4550 for a value of mode OUTMODE,
4551 with NARGS different arguments, passed as alternating rtx values
4552 and machine_modes to convert them to.
4553
4554 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
4555 `const' calls, LCT_PURE for `pure' calls, or other LCT_ value for
4556 other types of library calls. */
4557
4558 void
4559 emit_library_call (rtx orgfun, enum libcall_type fn_type,
4560 machine_mode outmode, int nargs, ...)
4561 {
4562 va_list p;
4563
4564 va_start (p, nargs);
4565 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4566 va_end (p);
4567 }
4568 \f
4569 /* Like emit_library_call except that an extra argument, VALUE,
4570 comes second and says where to store the result.
4571 (If VALUE is zero, this function chooses a convenient way
4572 to return the value.
4573
4574 This function returns an rtx for where the value is to be found.
4575 If VALUE is nonzero, VALUE is returned. */
4576
4577 rtx
4578 emit_library_call_value (rtx orgfun, rtx value,
4579 enum libcall_type fn_type,
4580 machine_mode outmode, int nargs, ...)
4581 {
4582 rtx result;
4583 va_list p;
4584
4585 va_start (p, nargs);
4586 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4587 nargs, p);
4588 va_end (p);
4589
4590 return result;
4591 }
4592 \f
4593
4594 /* Store pointer bounds argument ARG into Bounds Table entry
4595 associated with PARM. */
4596 static void
4597 store_bounds (struct arg_data *arg, struct arg_data *parm)
4598 {
4599 rtx slot = NULL, ptr = NULL, addr = NULL;
4600
4601 /* We may pass bounds not associated with any pointer. */
4602 if (!parm)
4603 {
4604 gcc_assert (arg->special_slot);
4605 slot = arg->special_slot;
4606 ptr = const0_rtx;
4607 }
4608 /* Find pointer associated with bounds and where it is
4609 passed. */
4610 else
4611 {
4612 if (!parm->reg)
4613 {
4614 gcc_assert (!arg->special_slot);
4615
4616 addr = adjust_address (parm->stack, Pmode, arg->pointer_offset);
4617 }
4618 else if (REG_P (parm->reg))
4619 {
4620 gcc_assert (arg->special_slot);
4621 slot = arg->special_slot;
4622
4623 if (MEM_P (parm->value))
4624 addr = adjust_address (parm->value, Pmode, arg->pointer_offset);
4625 else if (REG_P (parm->value))
4626 ptr = gen_rtx_SUBREG (Pmode, parm->value, arg->pointer_offset);
4627 else
4628 {
4629 gcc_assert (!arg->pointer_offset);
4630 ptr = parm->value;
4631 }
4632 }
4633 else
4634 {
4635 gcc_assert (GET_CODE (parm->reg) == PARALLEL);
4636
4637 gcc_assert (arg->special_slot);
4638 slot = arg->special_slot;
4639
4640 if (parm->parallel_value)
4641 ptr = chkp_get_value_with_offs (parm->parallel_value,
4642 GEN_INT (arg->pointer_offset));
4643 else
4644 gcc_unreachable ();
4645 }
4646 }
4647
4648 /* Expand bounds. */
4649 if (!arg->value)
4650 arg->value = expand_normal (arg->tree_value);
4651
4652 targetm.calls.store_bounds_for_arg (ptr, addr, arg->value, slot);
4653 }
4654
4655 /* Store a single argument for a function call
4656 into the register or memory area where it must be passed.
4657 *ARG describes the argument value and where to pass it.
4658
4659 ARGBLOCK is the address of the stack-block for all the arguments,
4660 or 0 on a machine where arguments are pushed individually.
4661
4662 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4663 so must be careful about how the stack is used.
4664
4665 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4666 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4667 that we need not worry about saving and restoring the stack.
4668
4669 FNDECL is the declaration of the function we are calling.
4670
4671 Return nonzero if this arg should cause sibcall failure,
4672 zero otherwise. */
4673
4674 static int
4675 store_one_arg (struct arg_data *arg, rtx argblock, int flags,
4676 int variable_size ATTRIBUTE_UNUSED, int reg_parm_stack_space)
4677 {
4678 tree pval = arg->tree_value;
4679 rtx reg = 0;
4680 int partial = 0;
4681 int used = 0;
4682 int i, lower_bound = 0, upper_bound = 0;
4683 int sibcall_failure = 0;
4684
4685 if (TREE_CODE (pval) == ERROR_MARK)
4686 return 1;
4687
4688 /* Push a new temporary level for any temporaries we make for
4689 this argument. */
4690 push_temp_slots ();
4691
4692 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4693 {
4694 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4695 save any previous data at that location. */
4696 if (argblock && ! variable_size && arg->stack)
4697 {
4698 if (ARGS_GROW_DOWNWARD)
4699 {
4700 /* stack_slot is negative, but we want to index stack_usage_map
4701 with positive values. */
4702 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4703 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4704 else
4705 upper_bound = 0;
4706
4707 lower_bound = upper_bound - arg->locate.size.constant;
4708 }
4709 else
4710 {
4711 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4712 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4713 else
4714 lower_bound = 0;
4715
4716 upper_bound = lower_bound + arg->locate.size.constant;
4717 }
4718
4719 i = lower_bound;
4720 /* Don't worry about things in the fixed argument area;
4721 it has already been saved. */
4722 if (i < reg_parm_stack_space)
4723 i = reg_parm_stack_space;
4724 while (i < upper_bound && stack_usage_map[i] == 0)
4725 i++;
4726
4727 if (i < upper_bound)
4728 {
4729 /* We need to make a save area. */
4730 unsigned int size = arg->locate.size.constant * BITS_PER_UNIT;
4731 machine_mode save_mode = mode_for_size (size, MODE_INT, 1);
4732 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
4733 rtx stack_area = gen_rtx_MEM (save_mode, adr);
4734
4735 if (save_mode == BLKmode)
4736 {
4737 arg->save_area
4738 = assign_temp (TREE_TYPE (arg->tree_value), 1, 1);
4739 preserve_temp_slots (arg->save_area);
4740 emit_block_move (validize_mem (copy_rtx (arg->save_area)),
4741 stack_area,
4742 GEN_INT (arg->locate.size.constant),
4743 BLOCK_OP_CALL_PARM);
4744 }
4745 else
4746 {
4747 arg->save_area = gen_reg_rtx (save_mode);
4748 emit_move_insn (arg->save_area, stack_area);
4749 }
4750 }
4751 }
4752 }
4753
4754 /* If this isn't going to be placed on both the stack and in registers,
4755 set up the register and number of words. */
4756 if (! arg->pass_on_stack)
4757 {
4758 if (flags & ECF_SIBCALL)
4759 reg = arg->tail_call_reg;
4760 else
4761 reg = arg->reg;
4762 partial = arg->partial;
4763 }
4764
4765 /* Being passed entirely in a register. We shouldn't be called in
4766 this case. */
4767 gcc_assert (reg == 0 || partial != 0);
4768
4769 /* If this arg needs special alignment, don't load the registers
4770 here. */
4771 if (arg->n_aligned_regs != 0)
4772 reg = 0;
4773
4774 /* If this is being passed partially in a register, we can't evaluate
4775 it directly into its stack slot. Otherwise, we can. */
4776 if (arg->value == 0)
4777 {
4778 /* stack_arg_under_construction is nonzero if a function argument is
4779 being evaluated directly into the outgoing argument list and
4780 expand_call must take special action to preserve the argument list
4781 if it is called recursively.
4782
4783 For scalar function arguments stack_usage_map is sufficient to
4784 determine which stack slots must be saved and restored. Scalar
4785 arguments in general have pass_on_stack == 0.
4786
4787 If this argument is initialized by a function which takes the
4788 address of the argument (a C++ constructor or a C function
4789 returning a BLKmode structure), then stack_usage_map is
4790 insufficient and expand_call must push the stack around the
4791 function call. Such arguments have pass_on_stack == 1.
4792
4793 Note that it is always safe to set stack_arg_under_construction,
4794 but this generates suboptimal code if set when not needed. */
4795
4796 if (arg->pass_on_stack)
4797 stack_arg_under_construction++;
4798
4799 arg->value = expand_expr (pval,
4800 (partial
4801 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4802 ? NULL_RTX : arg->stack,
4803 VOIDmode, EXPAND_STACK_PARM);
4804
4805 /* If we are promoting object (or for any other reason) the mode
4806 doesn't agree, convert the mode. */
4807
4808 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4809 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4810 arg->value, arg->unsignedp);
4811
4812 if (arg->pass_on_stack)
4813 stack_arg_under_construction--;
4814 }
4815
4816 /* Check for overlap with already clobbered argument area. */
4817 if ((flags & ECF_SIBCALL)
4818 && MEM_P (arg->value)
4819 && mem_overlaps_already_clobbered_arg_p (XEXP (arg->value, 0),
4820 arg->locate.size.constant))
4821 sibcall_failure = 1;
4822
4823 /* Don't allow anything left on stack from computation
4824 of argument to alloca. */
4825 if (flags & ECF_MAY_BE_ALLOCA)
4826 do_pending_stack_adjust ();
4827
4828 if (arg->value == arg->stack)
4829 /* If the value is already in the stack slot, we are done. */
4830 ;
4831 else if (arg->mode != BLKmode)
4832 {
4833 int size;
4834 unsigned int parm_align;
4835
4836 /* Argument is a scalar, not entirely passed in registers.
4837 (If part is passed in registers, arg->partial says how much
4838 and emit_push_insn will take care of putting it there.)
4839
4840 Push it, and if its size is less than the
4841 amount of space allocated to it,
4842 also bump stack pointer by the additional space.
4843 Note that in C the default argument promotions
4844 will prevent such mismatches. */
4845
4846 size = GET_MODE_SIZE (arg->mode);
4847 /* Compute how much space the push instruction will push.
4848 On many machines, pushing a byte will advance the stack
4849 pointer by a halfword. */
4850 #ifdef PUSH_ROUNDING
4851 size = PUSH_ROUNDING (size);
4852 #endif
4853 used = size;
4854
4855 /* Compute how much space the argument should get:
4856 round up to a multiple of the alignment for arguments. */
4857 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4858 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4859 / (PARM_BOUNDARY / BITS_PER_UNIT))
4860 * (PARM_BOUNDARY / BITS_PER_UNIT));
4861
4862 /* Compute the alignment of the pushed argument. */
4863 parm_align = arg->locate.boundary;
4864 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4865 {
4866 int pad = used - size;
4867 if (pad)
4868 {
4869 unsigned int pad_align = (pad & -pad) * BITS_PER_UNIT;
4870 parm_align = MIN (parm_align, pad_align);
4871 }
4872 }
4873
4874 /* This isn't already where we want it on the stack, so put it there.
4875 This can either be done with push or copy insns. */
4876 if (!emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
4877 parm_align, partial, reg, used - size, argblock,
4878 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4879 ARGS_SIZE_RTX (arg->locate.alignment_pad), true))
4880 sibcall_failure = 1;
4881
4882 /* Unless this is a partially-in-register argument, the argument is now
4883 in the stack. */
4884 if (partial == 0)
4885 arg->value = arg->stack;
4886 }
4887 else
4888 {
4889 /* BLKmode, at least partly to be pushed. */
4890
4891 unsigned int parm_align;
4892 int excess;
4893 rtx size_rtx;
4894
4895 /* Pushing a nonscalar.
4896 If part is passed in registers, PARTIAL says how much
4897 and emit_push_insn will take care of putting it there. */
4898
4899 /* Round its size up to a multiple
4900 of the allocation unit for arguments. */
4901
4902 if (arg->locate.size.var != 0)
4903 {
4904 excess = 0;
4905 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
4906 }
4907 else
4908 {
4909 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
4910 for BLKmode is careful to avoid it. */
4911 excess = (arg->locate.size.constant
4912 - int_size_in_bytes (TREE_TYPE (pval))
4913 + partial);
4914 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
4915 NULL_RTX, TYPE_MODE (sizetype),
4916 EXPAND_NORMAL);
4917 }
4918
4919 parm_align = arg->locate.boundary;
4920
4921 /* When an argument is padded down, the block is aligned to
4922 PARM_BOUNDARY, but the actual argument isn't. */
4923 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4924 {
4925 if (arg->locate.size.var)
4926 parm_align = BITS_PER_UNIT;
4927 else if (excess)
4928 {
4929 unsigned int excess_align = (excess & -excess) * BITS_PER_UNIT;
4930 parm_align = MIN (parm_align, excess_align);
4931 }
4932 }
4933
4934 if ((flags & ECF_SIBCALL) && MEM_P (arg->value))
4935 {
4936 /* emit_push_insn might not work properly if arg->value and
4937 argblock + arg->locate.offset areas overlap. */
4938 rtx x = arg->value;
4939 int i = 0;
4940
4941 if (XEXP (x, 0) == crtl->args.internal_arg_pointer
4942 || (GET_CODE (XEXP (x, 0)) == PLUS
4943 && XEXP (XEXP (x, 0), 0) ==
4944 crtl->args.internal_arg_pointer
4945 && CONST_INT_P (XEXP (XEXP (x, 0), 1))))
4946 {
4947 if (XEXP (x, 0) != crtl->args.internal_arg_pointer)
4948 i = INTVAL (XEXP (XEXP (x, 0), 1));
4949
4950 /* arg.locate doesn't contain the pretend_args_size offset,
4951 it's part of argblock. Ensure we don't count it in I. */
4952 if (STACK_GROWS_DOWNWARD)
4953 i -= crtl->args.pretend_args_size;
4954 else
4955 i += crtl->args.pretend_args_size;
4956
4957 /* expand_call should ensure this. */
4958 gcc_assert (!arg->locate.offset.var
4959 && arg->locate.size.var == 0
4960 && CONST_INT_P (size_rtx));
4961
4962 if (arg->locate.offset.constant > i)
4963 {
4964 if (arg->locate.offset.constant < i + INTVAL (size_rtx))
4965 sibcall_failure = 1;
4966 }
4967 else if (arg->locate.offset.constant < i)
4968 {
4969 /* Use arg->locate.size.constant instead of size_rtx
4970 because we only care about the part of the argument
4971 on the stack. */
4972 if (i < (arg->locate.offset.constant
4973 + arg->locate.size.constant))
4974 sibcall_failure = 1;
4975 }
4976 else
4977 {
4978 /* Even though they appear to be at the same location,
4979 if part of the outgoing argument is in registers,
4980 they aren't really at the same location. Check for
4981 this by making sure that the incoming size is the
4982 same as the outgoing size. */
4983 if (arg->locate.size.constant != INTVAL (size_rtx))
4984 sibcall_failure = 1;
4985 }
4986 }
4987 }
4988
4989 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4990 parm_align, partial, reg, excess, argblock,
4991 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4992 ARGS_SIZE_RTX (arg->locate.alignment_pad), false);
4993
4994 /* Unless this is a partially-in-register argument, the argument is now
4995 in the stack.
4996
4997 ??? Unlike the case above, in which we want the actual
4998 address of the data, so that we can load it directly into a
4999 register, here we want the address of the stack slot, so that
5000 it's properly aligned for word-by-word copying or something
5001 like that. It's not clear that this is always correct. */
5002 if (partial == 0)
5003 arg->value = arg->stack_slot;
5004 }
5005
5006 if (arg->reg && GET_CODE (arg->reg) == PARALLEL)
5007 {
5008 tree type = TREE_TYPE (arg->tree_value);
5009 arg->parallel_value
5010 = emit_group_load_into_temps (arg->reg, arg->value, type,
5011 int_size_in_bytes (type));
5012 }
5013
5014 /* Mark all slots this store used. */
5015 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
5016 && argblock && ! variable_size && arg->stack)
5017 for (i = lower_bound; i < upper_bound; i++)
5018 stack_usage_map[i] = 1;
5019
5020 /* Once we have pushed something, pops can't safely
5021 be deferred during the rest of the arguments. */
5022 NO_DEFER_POP;
5023
5024 /* Free any temporary slots made in processing this argument. */
5025 pop_temp_slots ();
5026
5027 return sibcall_failure;
5028 }
5029
5030 /* Nonzero if we do not know how to pass TYPE solely in registers. */
5031
5032 bool
5033 must_pass_in_stack_var_size (machine_mode mode ATTRIBUTE_UNUSED,
5034 const_tree type)
5035 {
5036 if (!type)
5037 return false;
5038
5039 /* If the type has variable size... */
5040 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5041 return true;
5042
5043 /* If the type is marked as addressable (it is required
5044 to be constructed into the stack)... */
5045 if (TREE_ADDRESSABLE (type))
5046 return true;
5047
5048 return false;
5049 }
5050
5051 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
5052 takes trailing padding of a structure into account. */
5053 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
5054
5055 bool
5056 must_pass_in_stack_var_size_or_pad (machine_mode mode, const_tree type)
5057 {
5058 if (!type)
5059 return false;
5060
5061 /* If the type has variable size... */
5062 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5063 return true;
5064
5065 /* If the type is marked as addressable (it is required
5066 to be constructed into the stack)... */
5067 if (TREE_ADDRESSABLE (type))
5068 return true;
5069
5070 /* If the padding and mode of the type is such that a copy into
5071 a register would put it into the wrong part of the register. */
5072 if (mode == BLKmode
5073 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
5074 && (FUNCTION_ARG_PADDING (mode, type)
5075 == (BYTES_BIG_ENDIAN ? upward : downward)))
5076 return true;
5077
5078 return false;
5079 }