1/* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989-2017 Free Software Foundation, Inc.
3
4This file is part of GCC.
5
6GCC is free software; you can redistribute it and/or modify it under
7the terms of the GNU General Public License as published by the Free
8Software Foundation; either version 3, or (at your option) any later
9version.
10
11GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12WARRANTY; without even the implied warranty of MERCHANTABILITY or
13FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14for more details.
15
16You should have received a copy of the GNU General Public License
17along 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 "memmodel.h"
30#include "tm_p.h"
31#include "stringpool.h"
32#include "expmed.h"
33#include "optabs.h"
34#include "emit-rtl.h"
35#include "cgraph.h"
36#include "diagnostic-core.h"
37#include "fold-const.h"
38#include "stor-layout.h"
39#include "varasm.h"
40#include "internal-fn.h"
41#include "dojump.h"
42#include "explow.h"
43#include "calls.h"
44#include "expr.h"
45#include "output.h"
46#include "langhooks.h"
47#include "except.h"
48#include "dbgcnt.h"
49#include "rtl-iter.h"
50#include "tree-chkp.h"
51#include "tree-vrp.h"
52#include "tree-ssanames.h"
53#include "rtl-chkp.h"
54#include "intl.h"
55#include "stringpool.h"
56#include "attribs.h"
57
58/* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
59#define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
60
61/* Data structure and subroutines used within expand_call. */
62
63struct arg_data
64{
65 /* Tree node for this argument. */
66 tree tree_value;
67 /* Mode for value; TYPE_MODE unless promoted. */
68 machine_mode mode;
69 /* Current RTL value for argument, or 0 if it isn't precomputed. */
70 rtx value;
71 /* Initially-compute RTL value for argument; only for const functions. */
72 rtx initial_value;
73 /* Register to pass this argument in, 0 if passed on stack, or an
74 PARALLEL if the arg is to be copied into multiple non-contiguous
75 registers. */
76 rtx reg;
77 /* Register to pass this argument in when generating tail call sequence.
78 This is not the same register as for normal calls on machines with
79 register windows. */
80 rtx tail_call_reg;
81 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
82 form for emit_group_move. */
83 rtx parallel_value;
84 /* If value is passed in neither reg nor stack, this field holds a number
85 of a special slot to be used. */
86 rtx special_slot;
87 /* For pointer bounds hold an index of parm bounds are bound to. -1 if
88 there is no such pointer. */
89 int pointer_arg;
90 /* If pointer_arg refers a structure, then pointer_offset holds an offset
91 of a pointer in this structure. */
92 int pointer_offset;
93 /* If REG was promoted from the actual mode of the argument expression,
94 indicates whether the promotion is sign- or zero-extended. */
95 int unsignedp;
96 /* Number of bytes to put in registers. 0 means put the whole arg
97 in registers. Also 0 if not passed in registers. */
98 int partial;
99 /* Nonzero if argument must be passed on stack.
100 Note that some arguments may be passed on the stack
101 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
102 pass_on_stack identifies arguments that *cannot* go in registers. */
103 int pass_on_stack;
104 /* Some fields packaged up for locate_and_pad_parm. */
105 struct locate_and_pad_arg_data locate;
106 /* Location on the stack at which parameter should be stored. The store
107 has already been done if STACK == VALUE. */
108 rtx stack;
109 /* Location on the stack of the start of this argument slot. This can
110 differ from STACK if this arg pads downward. This location is known
111 to be aligned to TARGET_FUNCTION_ARG_BOUNDARY. */
112 rtx stack_slot;
113 /* Place that this stack area has been saved, if needed. */
114 rtx save_area;
115 /* If an argument's alignment does not permit direct copying into registers,
116 copy in smaller-sized pieces into pseudos. These are stored in a
117 block pointed to by this field. The next field says how many
118 word-sized pseudos we made. */
119 rtx *aligned_regs;
120 int n_aligned_regs;
121};
122
123/* A vector of one char per byte of stack space. A byte if nonzero if
124 the corresponding stack location has been used.
125 This vector is used to prevent a function call within an argument from
126 clobbering any stack already set up. */
127static char *stack_usage_map;
128
129/* Size of STACK_USAGE_MAP. */
130static int highest_outgoing_arg_in_use;
131
132/* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
133 stack location's tail call argument has been already stored into the stack.
134 This bitmap is used to prevent sibling call optimization if function tries
135 to use parent's incoming argument slots when they have been already
136 overwritten with tail call arguments. */
137static sbitmap stored_args_map;
138
139/* stack_arg_under_construction is nonzero when an argument may be
140 initialized with a constructor call (including a C function that
141 returns a BLKmode struct) and expand_call must take special action
142 to make sure the object being constructed does not overlap the
143 argument list for the constructor call. */
144static int stack_arg_under_construction;
145
146static void emit_call_1 (rtx, tree, tree, tree, HOST_WIDE_INT, HOST_WIDE_INT,
147 HOST_WIDE_INT, rtx, rtx, int, rtx, int,
148 cumulative_args_t);
149static void precompute_register_parameters (int, struct arg_data *, int *);
150static void store_bounds (struct arg_data *, struct arg_data *);
151static int store_one_arg (struct arg_data *, rtx, int, int, int);
152static void store_unaligned_arguments_into_pseudos (struct arg_data *, int);
153static int finalize_must_preallocate (int, int, struct arg_data *,
154 struct args_size *);
155static void precompute_arguments (int, struct arg_data *);
156static int compute_argument_block_size (int, struct args_size *, tree, tree, int);
157static void initialize_argument_information (int, struct arg_data *,
158 struct args_size *, int,
159 tree, tree,
160 tree, tree, cumulative_args_t, int,
161 rtx *, int *, int *, int *,
162 bool *, bool);
163static void compute_argument_addresses (struct arg_data *, rtx, int);
164static rtx rtx_for_function_call (tree, tree);
165static void load_register_parameters (struct arg_data *, int, rtx *, int,
166 int, int *);
167static int special_function_p (const_tree, int);
168static int check_sibcall_argument_overlap_1 (rtx);
169static int check_sibcall_argument_overlap (rtx_insn *, struct arg_data *, int);
170
171static int combine_pending_stack_adjustment_and_call (int, struct args_size *,
172 unsigned int);
173static tree split_complex_types (tree);
174
175#ifdef REG_PARM_STACK_SPACE
176static rtx save_fixed_argument_area (int, rtx, int *, int *);
177static void restore_fixed_argument_area (rtx, rtx, int, int);
178#endif
179
180/* Force FUNEXP into a form suitable for the address of a CALL,
181 and return that as an rtx. Also load the static chain register
182 if FNDECL is a nested function.
183
184 CALL_FUSAGE points to a variable holding the prospective
185 CALL_INSN_FUNCTION_USAGE information. */
186
187rtx
188prepare_call_address (tree fndecl_or_type, rtx funexp, rtx static_chain_value,
189 rtx *call_fusage, int reg_parm_seen, int flags)
190{
191 /* Make a valid memory address and copy constants through pseudo-regs,
192 but not for a constant address if -fno-function-cse. */
193 if (GET_CODE (funexp) != SYMBOL_REF)
194 {
195 /* If it's an indirect call by descriptor, generate code to perform
196 runtime identification of the pointer and load the descriptor. */
197 if ((flags & ECF_BY_DESCRIPTOR) && !flag_trampolines)
198 {
199 const int bit_val = targetm.calls.custom_function_descriptors;
200 rtx call_lab = gen_label_rtx ();
201
202 gcc_assert (fndecl_or_type && TYPE_P (fndecl_or_type));
203 fndecl_or_type
204 = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL, NULL_TREE,
205 fndecl_or_type);
206 DECL_STATIC_CHAIN (fndecl_or_type) = 1;
207 rtx chain = targetm.calls.static_chain (fndecl_or_type, false);
208
209 if (GET_MODE (funexp) != Pmode)
210 funexp = convert_memory_address (Pmode, funexp);
211
212 /* Avoid long live ranges around function calls. */
213 funexp = copy_to_mode_reg (Pmode, funexp);
214
215 if (REG_P (chain))
216 emit_insn (gen_rtx_CLOBBER (VOIDmode, chain));
217
218 /* Emit the runtime identification pattern. */
219 rtx mask = gen_rtx_AND (Pmode, funexp, GEN_INT (bit_val));
220 emit_cmp_and_jump_insns (mask, const0_rtx, EQ, NULL_RTX, Pmode, 1,
221 call_lab);
222
223 /* Statically predict the branch to very likely taken. */
224 rtx_insn *insn = get_last_insn ();
225 if (JUMP_P (insn))
226 predict_insn_def (insn, PRED_BUILTIN_EXPECT, TAKEN);
227
228 /* Load the descriptor. */
229 rtx mem = gen_rtx_MEM (ptr_mode,
230 plus_constant (Pmode, funexp, - bit_val));
231 MEM_NOTRAP_P (mem) = 1;
232 mem = convert_memory_address (Pmode, mem);
233 emit_move_insn (chain, mem);
234
235 mem = gen_rtx_MEM (ptr_mode,
236 plus_constant (Pmode, funexp,
237 POINTER_SIZE / BITS_PER_UNIT
238 - bit_val));
239 MEM_NOTRAP_P (mem) = 1;
240 mem = convert_memory_address (Pmode, mem);
241 emit_move_insn (funexp, mem);
242
243 emit_label (call_lab);
244
245 if (REG_P (chain))
246 {
247 use_reg (call_fusage, chain);
248 STATIC_CHAIN_REG_P (chain) = 1;
249 }
250
251 /* Make sure we're not going to be overwritten below. */
252 gcc_assert (!static_chain_value);
253 }
254
255 /* If we are using registers for parameters, force the
256 function address into a register now. */
257 funexp = ((reg_parm_seen
258 && targetm.small_register_classes_for_mode_p (FUNCTION_MODE))
259 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
260 : memory_address (FUNCTION_MODE, funexp));
261 }
262 else
263 {
264 /* funexp could be a SYMBOL_REF represents a function pointer which is
265 of ptr_mode. In this case, it should be converted into address mode
266 to be a valid address for memory rtx pattern. See PR 64971. */
267 if (GET_MODE (funexp) != Pmode)
268 funexp = convert_memory_address (Pmode, funexp);
269
270 if (!(flags & ECF_SIBCALL))
271 {
272 if (!NO_FUNCTION_CSE && optimize && ! flag_no_function_cse)
273 funexp = force_reg (Pmode, funexp);
274 }
275 }
276
277 if (static_chain_value != 0
278 && (TREE_CODE (fndecl_or_type) != FUNCTION_DECL
279 || DECL_STATIC_CHAIN (fndecl_or_type)))
280 {
281 rtx chain;
282
283 chain = targetm.calls.static_chain (fndecl_or_type, false);
284 static_chain_value = convert_memory_address (Pmode, static_chain_value);
285
286 emit_move_insn (chain, static_chain_value);
287 if (REG_P (chain))
288 {
289 use_reg (call_fusage, chain);
290 STATIC_CHAIN_REG_P (chain) = 1;
291 }
292 }
293
294 return funexp;
295}
296
297/* Generate instructions to call function FUNEXP,
298 and optionally pop the results.
299 The CALL_INSN is the first insn generated.
300
301 FNDECL is the declaration node of the function. This is given to the
302 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
303 its own args.
304
305 FUNTYPE is the data type of the function. This is given to the hook
306 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
307 own args. We used to allow an identifier for library functions, but
308 that doesn't work when the return type is an aggregate type and the
309 calling convention says that the pointer to this aggregate is to be
310 popped by the callee.
311
312 STACK_SIZE is the number of bytes of arguments on the stack,
313 ROUNDED_STACK_SIZE is that number rounded up to
314 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
315 both to put into the call insn and to generate explicit popping
316 code if necessary.
317
318 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
319 It is zero if this call doesn't want a structure value.
320
321 NEXT_ARG_REG is the rtx that results from executing
322 targetm.calls.function_arg (&args_so_far, VOIDmode, void_type_node, true)
323 just after all the args have had their registers assigned.
324 This could be whatever you like, but normally it is the first
325 arg-register beyond those used for args in this call,
326 or 0 if all the arg-registers are used in this call.
327 It is passed on to `gen_call' so you can put this info in the call insn.
328
329 VALREG is a hard register in which a value is returned,
330 or 0 if the call does not return a value.
331
332 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
333 the args to this call were processed.
334 We restore `inhibit_defer_pop' to that value.
335
336 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
337 denote registers used by the called function. */
338
339static void
340emit_call_1 (rtx funexp, tree fntree ATTRIBUTE_UNUSED, tree fndecl ATTRIBUTE_UNUSED,
341 tree funtype ATTRIBUTE_UNUSED,
342 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED,
343 HOST_WIDE_INT rounded_stack_size,
344 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED,
345 rtx next_arg_reg ATTRIBUTE_UNUSED, rtx valreg,
346 int old_inhibit_defer_pop, rtx call_fusage, int ecf_flags,
347 cumulative_args_t args_so_far ATTRIBUTE_UNUSED)
348{
349 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
350 rtx call, funmem, pat;
351 int already_popped = 0;
352 HOST_WIDE_INT n_popped = 0;
353
354 /* Sibling call patterns never pop arguments (no sibcall(_value)_pop
355 patterns exist). Any popping that the callee does on return will
356 be from our caller's frame rather than ours. */
357 if (!(ecf_flags & ECF_SIBCALL))
358 {
359 n_popped += targetm.calls.return_pops_args (fndecl, funtype, stack_size);
360
361#ifdef CALL_POPS_ARGS
362 n_popped += CALL_POPS_ARGS (*get_cumulative_args (args_so_far));
363#endif
364 }
365
366 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
367 and we don't want to load it into a register as an optimization,
368 because prepare_call_address already did it if it should be done. */
369 if (GET_CODE (funexp) != SYMBOL_REF)
370 funexp = memory_address (FUNCTION_MODE, funexp);
371
372 funmem = gen_rtx_MEM (FUNCTION_MODE, funexp);
373 if (fndecl && TREE_CODE (fndecl) == FUNCTION_DECL)
374 {
375 tree t = fndecl;
376
377 /* Although a built-in FUNCTION_DECL and its non-__builtin
378 counterpart compare equal and get a shared mem_attrs, they
379 produce different dump output in compare-debug compilations,
380 if an entry gets garbage collected in one compilation, then
381 adds a different (but equivalent) entry, while the other
382 doesn't run the garbage collector at the same spot and then
383 shares the mem_attr with the equivalent entry. */
384 if (DECL_BUILT_IN_CLASS (t) == BUILT_IN_NORMAL)
385 {
386 tree t2 = builtin_decl_explicit (DECL_FUNCTION_CODE (t));
387 if (t2)
388 t = t2;
389 }
390
391 set_mem_expr (funmem, t);
392 }
393 else if (fntree)
394 set_mem_expr (funmem, build_simple_mem_ref (CALL_EXPR_FN (fntree)));
395
396 if (ecf_flags & ECF_SIBCALL)
397 {
398 if (valreg)
399 pat = targetm.gen_sibcall_value (valreg, funmem,
400 rounded_stack_size_rtx,
401 next_arg_reg, NULL_RTX);
402 else
403 pat = targetm.gen_sibcall (funmem, rounded_stack_size_rtx,
404 next_arg_reg, GEN_INT (struct_value_size));
405 }
406 /* If the target has "call" or "call_value" insns, then prefer them
407 if no arguments are actually popped. If the target does not have
408 "call" or "call_value" insns, then we must use the popping versions
409 even if the call has no arguments to pop. */
410 else if (n_popped > 0
411 || !(valreg
412 ? targetm.have_call_value ()
413 : targetm.have_call ()))
414 {
415 rtx n_pop = GEN_INT (n_popped);
416
417 /* If this subroutine pops its own args, record that in the call insn
418 if possible, for the sake of frame pointer elimination. */
419
420 if (valreg)
421 pat = targetm.gen_call_value_pop (valreg, funmem,
422 rounded_stack_size_rtx,
423 next_arg_reg, n_pop);
424 else
425 pat = targetm.gen_call_pop (funmem, rounded_stack_size_rtx,
426 next_arg_reg, n_pop);
427
428 already_popped = 1;
429 }
430 else
431 {
432 if (valreg)
433 pat = targetm.gen_call_value (valreg, funmem, rounded_stack_size_rtx,
434 next_arg_reg, NULL_RTX);
435 else
436 pat = targetm.gen_call (funmem, rounded_stack_size_rtx, next_arg_reg,
437 GEN_INT (struct_value_size));
438 }
439 emit_insn (pat);
440
441 /* Find the call we just emitted. */
442 rtx_call_insn *call_insn = last_call_insn ();
443
444 /* Some target create a fresh MEM instead of reusing the one provided
445 above. Set its MEM_EXPR. */
446 call = get_call_rtx_from (call_insn);
447 if (call
448 && MEM_EXPR (XEXP (call, 0)) == NULL_TREE
449 && MEM_EXPR (funmem) != NULL_TREE)
450 set_mem_expr (XEXP (call, 0), MEM_EXPR (funmem));
451
452 /* Mark instrumented calls. */
453 if (call && fntree)
454 CALL_EXPR_WITH_BOUNDS_P (call) = CALL_WITH_BOUNDS_P (fntree);
455
456 /* Put the register usage information there. */
457 add_function_usage_to (call_insn, call_fusage);
458
459 /* If this is a const call, then set the insn's unchanging bit. */
460 if (ecf_flags & ECF_CONST)
461 RTL_CONST_CALL_P (call_insn) = 1;
462
463 /* If this is a pure call, then set the insn's unchanging bit. */
464 if (ecf_flags & ECF_PURE)
465 RTL_PURE_CALL_P (call_insn) = 1;
466
467 /* If this is a const call, then set the insn's unchanging bit. */
468 if (ecf_flags & ECF_LOOPING_CONST_OR_PURE)
469 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn) = 1;
470
471 /* Create a nothrow REG_EH_REGION note, if needed. */
472 make_reg_eh_region_note (call_insn, ecf_flags, 0);
473
474 if (ecf_flags & ECF_NORETURN)
475 add_reg_note (call_insn, REG_NORETURN, const0_rtx);
476
477 if (ecf_flags & ECF_RETURNS_TWICE)
478 {
479 add_reg_note (call_insn, REG_SETJMP, const0_rtx);
480 cfun->calls_setjmp = 1;
481 }
482
483 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
484
485 /* Restore this now, so that we do defer pops for this call's args
486 if the context of the call as a whole permits. */
487 inhibit_defer_pop = old_inhibit_defer_pop;
488
489 if (n_popped > 0)
490 {
491 if (!already_popped)
492 CALL_INSN_FUNCTION_USAGE (call_insn)
493 = gen_rtx_EXPR_LIST (VOIDmode,
494 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
495 CALL_INSN_FUNCTION_USAGE (call_insn));
496 rounded_stack_size -= n_popped;
497 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
498 stack_pointer_delta -= n_popped;
499
500 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
501
502 /* If popup is needed, stack realign must use DRAP */
503 if (SUPPORTS_STACK_ALIGNMENT)
504 crtl->need_drap = true;
505 }
506 /* For noreturn calls when not accumulating outgoing args force
507 REG_ARGS_SIZE note to prevent crossjumping of calls with different
508 args sizes. */
509 else if (!ACCUMULATE_OUTGOING_ARGS && (ecf_flags & ECF_NORETURN) != 0)
510 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
511
512 if (!ACCUMULATE_OUTGOING_ARGS)
513 {
514 /* If returning from the subroutine does not automatically pop the args,
515 we need an instruction to pop them sooner or later.
516 Perhaps do it now; perhaps just record how much space to pop later.
517
518 If returning from the subroutine does pop the args, indicate that the
519 stack pointer will be changed. */
520
521 if (rounded_stack_size != 0)
522 {
523 if (ecf_flags & ECF_NORETURN)
524 /* Just pretend we did the pop. */
525 stack_pointer_delta -= rounded_stack_size;
526 else if (flag_defer_pop && inhibit_defer_pop == 0
527 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
528 pending_stack_adjust += rounded_stack_size;
529 else
530 adjust_stack (rounded_stack_size_rtx);
531 }
532 }
533 /* When we accumulate outgoing args, we must avoid any stack manipulations.
534 Restore the stack pointer to its original value now. Usually
535 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
536 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
537 popping variants of functions exist as well.
538
539 ??? We may optimize similar to defer_pop above, but it is
540 probably not worthwhile.
541
542 ??? It will be worthwhile to enable combine_stack_adjustments even for
543 such machines. */
544 else if (n_popped)
545 anti_adjust_stack (GEN_INT (n_popped));
546}
547
548/* Determine if the function identified by FNDECL is one with
549 special properties we wish to know about. Modify FLAGS accordingly.
550
551 For example, if the function might return more than one time (setjmp), then
552 set ECF_RETURNS_TWICE.
553
554 Set ECF_MAY_BE_ALLOCA for any memory allocation function that might allocate
555 space from the stack such as alloca. */
556
557static int
558special_function_p (const_tree fndecl, int flags)
559{
560 tree name_decl = DECL_NAME (fndecl);
561
562 /* For instrumentation clones we want to derive flags
563 from the original name. */
564 if (cgraph_node::get (fndecl)
565 && cgraph_node::get (fndecl)->instrumentation_clone)
566 name_decl = DECL_NAME (cgraph_node::get (fndecl)->orig_decl);
567
568 if (fndecl && name_decl
569 && IDENTIFIER_LENGTH (name_decl) <= 11
570 /* Exclude functions not at the file scope, or not `extern',
571 since they are not the magic functions we would otherwise
572 think they are.
573 FIXME: this should be handled with attributes, not with this
574 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
575 because you can declare fork() inside a function if you
576 wish. */
577 && (DECL_CONTEXT (fndecl) == NULL_TREE
578 || TREE_CODE (DECL_CONTEXT (fndecl)) == TRANSLATION_UNIT_DECL)
579 && TREE_PUBLIC (fndecl))
580 {
581 const char *name = IDENTIFIER_POINTER (name_decl);
582 const char *tname = name;
583
584 /* We assume that alloca will always be called by name. It
585 makes no sense to pass it as a pointer-to-function to
586 anything that does not understand its behavior. */
587 if (IDENTIFIER_LENGTH (name_decl) == 6
588 && name[0] == 'a'
589 && ! strcmp (name, "alloca"))
590 flags |= ECF_MAY_BE_ALLOCA;
591
592 /* Disregard prefix _ or __. */
593 if (name[0] == '_')
594 {
595 if (name[1] == '_')
596 tname += 2;
597 else
598 tname += 1;
599 }
600
601 /* ECF_RETURNS_TWICE is safe even for -ffreestanding. */
602 if (! strcmp (tname, "setjmp")
603 || ! strcmp (tname, "sigsetjmp")
604 || ! strcmp (name, "savectx")
605 || ! strcmp (name, "vfork")
606 || ! strcmp (name, "getcontext"))
607 flags |= ECF_RETURNS_TWICE;
608 }
609
610 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
611 && ALLOCA_FUNCTION_CODE_P (DECL_FUNCTION_CODE (fndecl)))
612 flags |= ECF_MAY_BE_ALLOCA;
613
614 return flags;
615}
616
617/* Similar to special_function_p; return a set of ERF_ flags for the
618 function FNDECL. */
619static int
620decl_return_flags (tree fndecl)
621{
622 tree attr;
623 tree type = TREE_TYPE (fndecl);
624 if (!type)
625 return 0;
626
627 attr = lookup_attribute ("fn spec", TYPE_ATTRIBUTES (type));
628 if (!attr)
629 return 0;
630
631 attr = TREE_VALUE (TREE_VALUE (attr));
632 if (!attr || TREE_STRING_LENGTH (attr) < 1)
633 return 0;
634
635 switch (TREE_STRING_POINTER (attr)[0])
636 {
637 case '1':
638 case '2':
639 case '3':
640 case '4':
641 return ERF_RETURNS_ARG | (TREE_STRING_POINTER (attr)[0] - '1');
642
643 case 'm':
644 return ERF_NOALIAS;
645
646 case '.':
647 default:
648 return 0;
649 }
650}
651
652/* Return nonzero when FNDECL represents a call to setjmp. */
653
654int
655setjmp_call_p (const_tree fndecl)
656{
657 if (DECL_IS_RETURNS_TWICE (fndecl))
658 return ECF_RETURNS_TWICE;
659 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
660}
661
662
663/* Return true if STMT may be an alloca call. */
664
665bool
666gimple_maybe_alloca_call_p (const gimple *stmt)
667{
668 tree fndecl;
669
670 if (!is_gimple_call (stmt))
671 return false;
672
673 fndecl = gimple_call_fndecl (stmt);
674 if (fndecl && (special_function_p (fndecl, 0) & ECF_MAY_BE_ALLOCA))
675 return true;
676
677 return false;
678}
679
680/* Return true if STMT is a builtin alloca call. */
681
682bool
683gimple_alloca_call_p (const gimple *stmt)
684{
685 tree fndecl;
686
687 if (!is_gimple_call (stmt))
688 return false;
689
690 fndecl = gimple_call_fndecl (stmt);
691 if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
692 switch (DECL_FUNCTION_CODE (fndecl))
693 {
694 CASE_BUILT_IN_ALLOCA:
695 return true;
696 default:
697 break;
698 }
699
700 return false;
701}
702
703/* Return true when exp contains a builtin alloca call. */
704
705bool
706alloca_call_p (const_tree exp)
707{
708 tree fndecl;
709 if (TREE_CODE (exp) == CALL_EXPR
710 && (fndecl = get_callee_fndecl (exp))
711 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
712 switch (DECL_FUNCTION_CODE (fndecl))
713 {
714 CASE_BUILT_IN_ALLOCA:
715 return true;
716 default:
717 break;
718 }
719
720 return false;
721}
722
723/* Return TRUE if FNDECL is either a TM builtin or a TM cloned
724 function. Return FALSE otherwise. */
725
726static bool
727is_tm_builtin (const_tree fndecl)
728{
729 if (fndecl == NULL)
730 return false;
731
732 if (decl_is_tm_clone (fndecl))
733 return true;
734
735 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
736 {
737 switch (DECL_FUNCTION_CODE (fndecl))
738 {
739 case BUILT_IN_TM_COMMIT:
740 case BUILT_IN_TM_COMMIT_EH:
741 case BUILT_IN_TM_ABORT:
742 case BUILT_IN_TM_IRREVOCABLE:
743 case BUILT_IN_TM_GETTMCLONE_IRR:
744 case BUILT_IN_TM_MEMCPY:
745 case BUILT_IN_TM_MEMMOVE:
746 case BUILT_IN_TM_MEMSET:
747 CASE_BUILT_IN_TM_STORE (1):
748 CASE_BUILT_IN_TM_STORE (2):
749 CASE_BUILT_IN_TM_STORE (4):
750 CASE_BUILT_IN_TM_STORE (8):
751 CASE_BUILT_IN_TM_STORE (FLOAT):
752 CASE_BUILT_IN_TM_STORE (DOUBLE):
753 CASE_BUILT_IN_TM_STORE (LDOUBLE):
754 CASE_BUILT_IN_TM_STORE (M64):
755 CASE_BUILT_IN_TM_STORE (M128):
756 CASE_BUILT_IN_TM_STORE (M256):
757 CASE_BUILT_IN_TM_LOAD (1):
758 CASE_BUILT_IN_TM_LOAD (2):
759 CASE_BUILT_IN_TM_LOAD (4):
760 CASE_BUILT_IN_TM_LOAD (8):
761 CASE_BUILT_IN_TM_LOAD (FLOAT):
762 CASE_BUILT_IN_TM_LOAD (DOUBLE):
763 CASE_BUILT_IN_TM_LOAD (LDOUBLE):
764 CASE_BUILT_IN_TM_LOAD (M64):
765 CASE_BUILT_IN_TM_LOAD (M128):
766 CASE_BUILT_IN_TM_LOAD (M256):
767 case BUILT_IN_TM_LOG:
768 case BUILT_IN_TM_LOG_1:
769 case BUILT_IN_TM_LOG_2:
770 case BUILT_IN_TM_LOG_4:
771 case BUILT_IN_TM_LOG_8:
772 case BUILT_IN_TM_LOG_FLOAT:
773 case BUILT_IN_TM_LOG_DOUBLE:
774 case BUILT_IN_TM_LOG_LDOUBLE:
775 case BUILT_IN_TM_LOG_M64:
776 case BUILT_IN_TM_LOG_M128:
777 case BUILT_IN_TM_LOG_M256:
778 return true;
779 default:
780 break;
781 }
782 }
783 return false;
784}
785
786/* Detect flags (function attributes) from the function decl or type node. */
787
788int
789flags_from_decl_or_type (const_tree exp)
790{
791 int flags = 0;
792
793 if (DECL_P (exp))
794 {
795 /* The function exp may have the `malloc' attribute. */
796 if (DECL_IS_MALLOC (exp))
797 flags |= ECF_MALLOC;
798
799 /* The function exp may have the `returns_twice' attribute. */
800 if (DECL_IS_RETURNS_TWICE (exp))
801 flags |= ECF_RETURNS_TWICE;
802
803 /* Process the pure and const attributes. */
804 if (TREE_READONLY (exp))
805 flags |= ECF_CONST;
806 if (DECL_PURE_P (exp))
807 flags |= ECF_PURE;
808 if (DECL_LOOPING_CONST_OR_PURE_P (exp))
809 flags |= ECF_LOOPING_CONST_OR_PURE;
810
811 if (DECL_IS_NOVOPS (exp))
812 flags |= ECF_NOVOPS;
813 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp)))
814 flags |= ECF_LEAF;
815 if (lookup_attribute ("cold", DECL_ATTRIBUTES (exp)))
816 flags |= ECF_COLD;
817
818 if (TREE_NOTHROW (exp))
819 flags |= ECF_NOTHROW;
820
821 if (flag_tm)
822 {
823 if (is_tm_builtin (exp))
824 flags |= ECF_TM_BUILTIN;
825 else if ((flags & (ECF_CONST|ECF_NOVOPS)) != 0
826 || lookup_attribute ("transaction_pure",
827 TYPE_ATTRIBUTES (TREE_TYPE (exp))))
828 flags |= ECF_TM_PURE;
829 }
830
831 flags = special_function_p (exp, flags);
832 }
833 else if (TYPE_P (exp))
834 {
835 if (TYPE_READONLY (exp))
836 flags |= ECF_CONST;
837
838 if (flag_tm
839 && ((flags & ECF_CONST) != 0
840 || lookup_attribute ("transaction_pure", TYPE_ATTRIBUTES (exp))))
841 flags |= ECF_TM_PURE;
842 }
843 else
844 gcc_unreachable ();
845
846 if (TREE_THIS_VOLATILE (exp))
847 {
848 flags |= ECF_NORETURN;
849 if (flags & (ECF_CONST|ECF_PURE))
850 flags |= ECF_LOOPING_CONST_OR_PURE;
851 }
852
853 return flags;
854}
855
856/* Detect flags from a CALL_EXPR. */
857
858int
859call_expr_flags (const_tree t)
860{
861 int flags;
862 tree decl = get_callee_fndecl (t);
863
864 if (decl)
865 flags = flags_from_decl_or_type (decl);
866 else if (CALL_EXPR_FN (t) == NULL_TREE)
867 flags = internal_fn_flags (CALL_EXPR_IFN (t));
868 else
869 {
870 tree type = TREE_TYPE (CALL_EXPR_FN (t));
871 if (type && TREE_CODE (type) == POINTER_TYPE)
872 flags = flags_from_decl_or_type (TREE_TYPE (type));
873 else
874 flags = 0;
875 if (CALL_EXPR_BY_DESCRIPTOR (t))
876 flags |= ECF_BY_DESCRIPTOR;
877 }
878
879 return flags;
880}
881
882/* Return true if TYPE should be passed by invisible reference. */
883
884bool
885pass_by_reference (CUMULATIVE_ARGS *ca, machine_mode mode,
886 tree type, bool named_arg)
887{
888 if (type)
889 {
890 /* If this type contains non-trivial constructors, then it is
891 forbidden for the middle-end to create any new copies. */
892 if (TREE_ADDRESSABLE (type))
893 return true;
894
895 /* GCC post 3.4 passes *all* variable sized types by reference. */
896 if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
897 return true;
898
899 /* If a record type should be passed the same as its first (and only)
900 member, use the type and mode of that member. */
901 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
902 {
903 type = TREE_TYPE (first_field (type));
904 mode = TYPE_MODE (type);
905 }
906 }
907
908 return targetm.calls.pass_by_reference (pack_cumulative_args (ca), mode,
909 type, named_arg);
910}
911
912/* Return true if TYPE, which is passed by reference, should be callee
913 copied instead of caller copied. */
914
915bool
916reference_callee_copied (CUMULATIVE_ARGS *ca, machine_mode mode,
917 tree type, bool named_arg)
918{
919 if (type && TREE_ADDRESSABLE (type))
920 return false;
921 return targetm.calls.callee_copies (pack_cumulative_args (ca), mode, type,
922 named_arg);
923}
924
925
926/* Precompute all register parameters as described by ARGS, storing values
927 into fields within the ARGS array.
928
929 NUM_ACTUALS indicates the total number elements in the ARGS array.
930
931 Set REG_PARM_SEEN if we encounter a register parameter. */
932
933static void
934precompute_register_parameters (int num_actuals, struct arg_data *args,
935 int *reg_parm_seen)
936{
937 int i;
938
939 *reg_parm_seen = 0;
940
941 for (i = 0; i < num_actuals; i++)
942 if (args[i].reg != 0 && ! args[i].pass_on_stack)
943 {
944 *reg_parm_seen = 1;
945
946 if (args[i].value == 0)
947 {
948 push_temp_slots ();
949 args[i].value = expand_normal (args[i].tree_value);
950 preserve_temp_slots (args[i].value);
951 pop_temp_slots ();
952 }
953
954 /* If we are to promote the function arg to a wider mode,
955 do it now. */
956
957 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
958 args[i].value
959 = convert_modes (args[i].mode,
960 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
961 args[i].value, args[i].unsignedp);
962
963 /* If the value is a non-legitimate constant, force it into a
964 pseudo now. TLS symbols sometimes need a call to resolve. */
965 if (CONSTANT_P (args[i].value)
966 && !targetm.legitimate_constant_p (args[i].mode, args[i].value))
967 args[i].value = force_reg (args[i].mode, args[i].value);
968
969 /* If we're going to have to load the value by parts, pull the
970 parts into pseudos. The part extraction process can involve
971 non-trivial computation. */
972 if (GET_CODE (args[i].reg) == PARALLEL)
973 {
974 tree type = TREE_TYPE (args[i].tree_value);
975 args[i].parallel_value
976 = emit_group_load_into_temps (args[i].reg, args[i].value,
977 type, int_size_in_bytes (type));
978 }
979
980 /* If the value is expensive, and we are inside an appropriately
981 short loop, put the value into a pseudo and then put the pseudo
982 into the hard reg.
983
984 For small register classes, also do this if this call uses
985 register parameters. This is to avoid reload conflicts while
986 loading the parameters registers. */
987
988 else if ((! (REG_P (args[i].value)
989 || (GET_CODE (args[i].value) == SUBREG
990 && REG_P (SUBREG_REG (args[i].value)))))
991 && args[i].mode != BLKmode
992 && (set_src_cost (args[i].value, args[i].mode,
993 optimize_insn_for_speed_p ())
994 > COSTS_N_INSNS (1))
995 && ((*reg_parm_seen
996 && targetm.small_register_classes_for_mode_p (args[i].mode))
997 || optimize))
998 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
999 }
1000}
1001
1002#ifdef REG_PARM_STACK_SPACE
1003
1004 /* The argument list is the property of the called routine and it
1005 may clobber it. If the fixed area has been used for previous
1006 parameters, we must save and restore it. */
1007
1008static rtx
1009save_fixed_argument_area (int reg_parm_stack_space, rtx argblock, int *low_to_save, int *high_to_save)
1010{
1011 int low;
1012 int high;
1013
1014 /* Compute the boundary of the area that needs to be saved, if any. */
1015 high = reg_parm_stack_space;
1016 if (ARGS_GROW_DOWNWARD)
1017 high += 1;
1018
1019 if (high > highest_outgoing_arg_in_use)
1020 high = highest_outgoing_arg_in_use;
1021
1022 for (low = 0; low < high; low++)
1023 if (stack_usage_map[low] != 0)
1024 {
1025 int num_to_save;
1026 machine_mode save_mode;
1027 int delta;
1028 rtx addr;
1029 rtx stack_area;
1030 rtx save_area;
1031
1032 while (stack_usage_map[--high] == 0)
1033 ;
1034
1035 *low_to_save = low;
1036 *high_to_save = high;
1037
1038 num_to_save = high - low + 1;
1039
1040 /* If we don't have the required alignment, must do this
1041 in BLKmode. */
1042 scalar_int_mode imode;
1043 if (int_mode_for_size (num_to_save * BITS_PER_UNIT, 1).exists (&imode)
1044 && (low & (MIN (GET_MODE_SIZE (imode),
1045 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)) == 0)
1046 save_mode = imode;
1047 else
1048 save_mode = BLKmode;
1049
1050 if (ARGS_GROW_DOWNWARD)
1051 delta = -high;
1052 else
1053 delta = low;
1054
1055 addr = plus_constant (Pmode, argblock, delta);
1056 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
1057
1058 set_mem_align (stack_area, PARM_BOUNDARY);
1059 if (save_mode == BLKmode)
1060 {
1061 save_area = assign_stack_temp (BLKmode, num_to_save);
1062 emit_block_move (validize_mem (save_area), stack_area,
1063 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
1064 }
1065 else
1066 {
1067 save_area = gen_reg_rtx (save_mode);
1068 emit_move_insn (save_area, stack_area);
1069 }
1070
1071 return save_area;
1072 }
1073
1074 return NULL_RTX;
1075}
1076
1077static void
1078restore_fixed_argument_area (rtx save_area, rtx argblock, int high_to_save, int low_to_save)
1079{
1080 machine_mode save_mode = GET_MODE (save_area);
1081 int delta;
1082 rtx addr, stack_area;
1083
1084 if (ARGS_GROW_DOWNWARD)
1085 delta = -high_to_save;
1086 else
1087 delta = low_to_save;
1088
1089 addr = plus_constant (Pmode, argblock, delta);
1090 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
1091 set_mem_align (stack_area, PARM_BOUNDARY);
1092
1093 if (save_mode != BLKmode)
1094 emit_move_insn (stack_area, save_area);
1095 else
1096 emit_block_move (stack_area, validize_mem (save_area),
1097 GEN_INT (high_to_save - low_to_save + 1),
1098 BLOCK_OP_CALL_PARM);
1099}
1100#endif /* REG_PARM_STACK_SPACE */
1101
1102/* If any elements in ARGS refer to parameters that are to be passed in
1103 registers, but not in memory, and whose alignment does not permit a
1104 direct copy into registers. Copy the values into a group of pseudos
1105 which we will later copy into the appropriate hard registers.
1106
1107 Pseudos for each unaligned argument will be stored into the array
1108 args[argnum].aligned_regs. The caller is responsible for deallocating
1109 the aligned_regs array if it is nonzero. */
1110
1111static void
1112store_unaligned_arguments_into_pseudos (struct arg_data *args, int num_actuals)
1113{
1114 int i, j;
1115
1116 for (i = 0; i < num_actuals; i++)
1117 if (args[i].reg != 0 && ! args[i].pass_on_stack
1118 && GET_CODE (args[i].reg) != PARALLEL
1119 && args[i].mode == BLKmode
1120 && MEM_P (args[i].value)
1121 && (MEM_ALIGN (args[i].value)
1122 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1123 {
1124 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1125 int endian_correction = 0;
1126
1127 if (args[i].partial)
1128 {
1129 gcc_assert (args[i].partial % UNITS_PER_WORD == 0);
1130 args[i].n_aligned_regs = args[i].partial / UNITS_PER_WORD;
1131 }
1132 else
1133 {
1134 args[i].n_aligned_regs
1135 = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
1136 }
1137
1138 args[i].aligned_regs = XNEWVEC (rtx, args[i].n_aligned_regs);
1139
1140 /* Structures smaller than a word are normally aligned to the
1141 least significant byte. On a BYTES_BIG_ENDIAN machine,
1142 this means we must skip the empty high order bytes when
1143 calculating the bit offset. */
1144 if (bytes < UNITS_PER_WORD
1145#ifdef BLOCK_REG_PADDING
1146 && (BLOCK_REG_PADDING (args[i].mode,
1147 TREE_TYPE (args[i].tree_value), 1)
1148 == PAD_DOWNWARD)
1149#else
1150 && BYTES_BIG_ENDIAN
1151#endif
1152 )
1153 endian_correction = BITS_PER_WORD - bytes * BITS_PER_UNIT;
1154
1155 for (j = 0; j < args[i].n_aligned_regs; j++)
1156 {
1157 rtx reg = gen_reg_rtx (word_mode);
1158 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1159 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1160
1161 args[i].aligned_regs[j] = reg;
1162 word = extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1163 word_mode, word_mode, false, NULL);
1164
1165 /* There is no need to restrict this code to loading items
1166 in TYPE_ALIGN sized hunks. The bitfield instructions can
1167 load up entire word sized registers efficiently.
1168
1169 ??? This may not be needed anymore.
1170 We use to emit a clobber here but that doesn't let later
1171 passes optimize the instructions we emit. By storing 0 into
1172 the register later passes know the first AND to zero out the
1173 bitfield being set in the register is unnecessary. The store
1174 of 0 will be deleted as will at least the first AND. */
1175
1176 emit_move_insn (reg, const0_rtx);
1177
1178 bytes -= bitsize / BITS_PER_UNIT;
1179 store_bit_field (reg, bitsize, endian_correction, 0, 0,
1180 word_mode, word, false);
1181 }
1182 }
1183}
1184
1185/* The limit set by -Walloc-larger-than=. */
1186static GTY(()) tree alloc_object_size_limit;
1187
1188/* Initialize ALLOC_OBJECT_SIZE_LIMIT based on the -Walloc-size-larger-than=
1189 setting if the option is specified, or to the maximum object size if it
1190 is not. Return the initialized value. */
1191
1192static tree
1193alloc_max_size (void)
1194{
1195 if (!alloc_object_size_limit)
1196 {
1197 alloc_object_size_limit = TYPE_MAX_VALUE (ssizetype);
1198
1199 if (warn_alloc_size_limit)
1200 {
1201 char *end = NULL;
1202 errno = 0;
1203 unsigned HOST_WIDE_INT unit = 1;
1204 unsigned HOST_WIDE_INT limit
1205 = strtoull (warn_alloc_size_limit, &end, 10);
1206
1207 if (!errno)
1208 {
1209 if (end && *end)
1210 {
1211 /* Numeric option arguments are at most INT_MAX. Make it
1212 possible to specify a larger value by accepting common
1213 suffixes. */
1214 if (!strcmp (end, "kB"))
1215 unit = 1000;
1216 else if (!strcasecmp (end, "KiB") || strcmp (end, "KB"))
1217 unit = 1024;
1218 else if (!strcmp (end, "MB"))
1219 unit = HOST_WIDE_INT_UC (1000) * 1000;
1220 else if (!strcasecmp (end, "MiB"))
1221 unit = HOST_WIDE_INT_UC (1024) * 1024;
1222 else if (!strcasecmp (end, "GB"))
1223 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000;
1224 else if (!strcasecmp (end, "GiB"))
1225 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024;
1226 else if (!strcasecmp (end, "TB"))
1227 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000 * 1000;
1228 else if (!strcasecmp (end, "TiB"))
1229 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024 * 1024;
1230 else if (!strcasecmp (end, "PB"))
1231 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000 * 1000 * 1000;
1232 else if (!strcasecmp (end, "PiB"))
1233 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024 * 1024 * 1024;
1234 else if (!strcasecmp (end, "EB"))
1235 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000 * 1000 * 1000
1236 * 1000;
1237 else if (!strcasecmp (end, "EiB"))
1238 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024 * 1024 * 1024
1239 * 1024;
1240 else
1241 unit = 0;
1242 }
1243
1244 if (unit)
1245 {
1246 widest_int w = wi::mul (limit, unit);
1247 if (w < wi::to_widest (alloc_object_size_limit))
1248 alloc_object_size_limit = wide_int_to_tree (ssizetype, w);
1249 }
1250 }
1251 }
1252 }
1253 return alloc_object_size_limit;
1254}
1255
1256/* Return true when EXP's range can be determined and set RANGE[] to it
1257 after adjusting it if necessary to make EXP a valid size argument to
1258 an allocation function declared with attribute alloc_size (whose
1259 argument may be signed), or to a string manipulation function like
1260 memset. */
1261
1262bool
1263get_size_range (tree exp, tree range[2])
1264{
1265 if (tree_fits_uhwi_p (exp))
1266 {
1267 /* EXP is a constant. */
1268 range[0] = range[1] = exp;
1269 return true;
1270 }
1271
1272 wide_int min, max;
1273 enum value_range_type range_type
1274 = ((TREE_CODE (exp) == SSA_NAME && INTEGRAL_TYPE_P (TREE_TYPE (exp)))
1275 ? get_range_info (exp, &min, &max) : VR_VARYING);
1276
1277 if (range_type == VR_VARYING)
1278 {
1279 /* No range information available. */
1280 range[0] = NULL_TREE;
1281 range[1] = NULL_TREE;
1282 return false;
1283 }
1284
1285 tree exptype = TREE_TYPE (exp);
1286 unsigned expprec = TYPE_PRECISION (exptype);
1287
1288 bool signed_p = !TYPE_UNSIGNED (exptype);
1289
1290 if (range_type == VR_ANTI_RANGE)
1291 {
1292 if (signed_p)
1293 {
1294 if (wi::les_p (max, 0))
1295 {
1296 /* EXP is not in a strictly negative range. That means
1297 it must be in some (not necessarily strictly) positive
1298 range which includes zero. Since in signed to unsigned
1299 conversions negative values end up converted to large
1300 positive values, and otherwise they are not valid sizes,
1301 the resulting range is in both cases [0, TYPE_MAX]. */
1302 min = wi::zero (expprec);
1303 max = wi::to_wide (TYPE_MAX_VALUE (exptype));
1304 }
1305 else if (wi::les_p (min - 1, 0))
1306 {
1307 /* EXP is not in a negative-positive range. That means EXP
1308 is either negative, or greater than max. Since negative
1309 sizes are invalid make the range [MAX + 1, TYPE_MAX]. */
1310 min = max + 1;
1311 max = wi::to_wide (TYPE_MAX_VALUE (exptype));
1312 }
1313 else
1314 {
1315 max = min - 1;
1316 min = wi::zero (expprec);
1317 }
1318 }
1319 else if (wi::eq_p (0, min - 1))
1320 {
1321 /* EXP is unsigned and not in the range [1, MAX]. That means
1322 it's either zero or greater than MAX. Even though 0 would
1323 normally be detected by -Walloc-zero set the range to
1324 [MAX, TYPE_MAX] so that when MAX is greater than the limit
1325 the whole range is diagnosed. */
1326 min = max + 1;
1327 max = wi::to_wide (TYPE_MAX_VALUE (exptype));
1328 }
1329 else
1330 {
1331 max = min - 1;
1332 min = wi::zero (expprec);
1333 }
1334 }
1335
1336 range[0] = wide_int_to_tree (exptype, min);
1337 range[1] = wide_int_to_tree (exptype, max);
1338
1339 return true;
1340}
1341
1342/* Diagnose a call EXP to function FN decorated with attribute alloc_size
1343 whose argument numbers given by IDX with values given by ARGS exceed
1344 the maximum object size or cause an unsigned oveflow (wrapping) when
1345 multiplied. When ARGS[0] is null the function does nothing. ARGS[1]
1346 may be null for functions like malloc, and non-null for those like
1347 calloc that are decorated with a two-argument attribute alloc_size. */
1348
1349void
1350maybe_warn_alloc_args_overflow (tree fn, tree exp, tree args[2], int idx[2])
1351{
1352 /* The range each of the (up to) two arguments is known to be in. */
1353 tree argrange[2][2] = { { NULL_TREE, NULL_TREE }, { NULL_TREE, NULL_TREE } };
1354
1355 /* Maximum object size set by -Walloc-size-larger-than= or SIZE_MAX / 2. */
1356 tree maxobjsize = alloc_max_size ();
1357
1358 location_t loc = EXPR_LOCATION (exp);
1359
1360 bool warned = false;
1361
1362 /* Validate each argument individually. */
1363 for (unsigned i = 0; i != 2 && args[i]; ++i)
1364 {
1365 if (TREE_CODE (args[i]) == INTEGER_CST)
1366 {
1367 argrange[i][0] = args[i];
1368 argrange[i][1] = args[i];
1369
1370 if (tree_int_cst_lt (args[i], integer_zero_node))
1371 {
1372 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1373 "%Kargument %i value %qE is negative",
1374 exp, idx[i] + 1, args[i]);
1375 }
1376 else if (integer_zerop (args[i]))
1377 {
1378 /* Avoid issuing -Walloc-zero for allocation functions other
1379 than __builtin_alloca that are declared with attribute
1380 returns_nonnull because there's no portability risk. This
1381 avoids warning for such calls to libiberty's xmalloc and
1382 friends.
1383 Also avoid issuing the warning for calls to function named
1384 "alloca". */
1385 if ((DECL_FUNCTION_CODE (fn) == BUILT_IN_ALLOCA
1386 && IDENTIFIER_LENGTH (DECL_NAME (fn)) != 6)
1387 || (DECL_FUNCTION_CODE (fn) != BUILT_IN_ALLOCA
1388 && !lookup_attribute ("returns_nonnull",
1389 TYPE_ATTRIBUTES (TREE_TYPE (fn)))))
1390 warned = warning_at (loc, OPT_Walloc_zero,
1391 "%Kargument %i value is zero",
1392 exp, idx[i] + 1);
1393 }
1394 else if (tree_int_cst_lt (maxobjsize, args[i]))
1395 {
1396 /* G++ emits calls to ::operator new[](SIZE_MAX) in C++98
1397 mode and with -fno-exceptions as a way to indicate array
1398 size overflow. There's no good way to detect C++98 here
1399 so avoid diagnosing these calls for all C++ modes. */
1400 if (i == 0
1401 && !args[1]
1402 && lang_GNU_CXX ()
1403 && DECL_IS_OPERATOR_NEW (fn)
1404 && integer_all_onesp (args[i]))
1405 continue;
1406
1407 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1408 "%Kargument %i value %qE exceeds "
1409 "maximum object size %E",
1410 exp, idx[i] + 1, args[i], maxobjsize);
1411 }
1412 }
1413 else if (TREE_CODE (args[i]) == SSA_NAME
1414 && get_size_range (args[i], argrange[i]))
1415 {
1416 /* Verify that the argument's range is not negative (including
1417 upper bound of zero). */
1418 if (tree_int_cst_lt (argrange[i][0], integer_zero_node)
1419 && tree_int_cst_le (argrange[i][1], integer_zero_node))
1420 {
1421 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1422 "%Kargument %i range [%E, %E] is negative",
1423 exp, idx[i] + 1,
1424 argrange[i][0], argrange[i][1]);
1425 }
1426 else if (tree_int_cst_lt (maxobjsize, argrange[i][0]))
1427 {
1428 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1429 "%Kargument %i range [%E, %E] exceeds "
1430 "maximum object size %E",
1431 exp, idx[i] + 1,
1432 argrange[i][0], argrange[i][1],
1433 maxobjsize);
1434 }
1435 }
1436 }
1437
1438 if (!argrange[0])
1439 return;
1440
1441 /* For a two-argument alloc_size, validate the product of the two
1442 arguments if both of their values or ranges are known. */
1443 if (!warned && tree_fits_uhwi_p (argrange[0][0])
1444 && argrange[1][0] && tree_fits_uhwi_p (argrange[1][0])
1445 && !integer_onep (argrange[0][0])
1446 && !integer_onep (argrange[1][0]))
1447 {
1448 /* Check for overflow in the product of a function decorated with
1449 attribute alloc_size (X, Y). */
1450 unsigned szprec = TYPE_PRECISION (size_type_node);
1451 wide_int x = wi::to_wide (argrange[0][0], szprec);
1452 wide_int y = wi::to_wide (argrange[1][0], szprec);
1453
1454 bool vflow;
1455 wide_int prod = wi::umul (x, y, &vflow);
1456
1457 if (vflow)
1458 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1459 "%Kproduct %<%E * %E%> of arguments %i and %i "
1460 "exceeds %<SIZE_MAX%>",
1461 exp, argrange[0][0], argrange[1][0],
1462 idx[0] + 1, idx[1] + 1);
1463 else if (wi::ltu_p (wi::to_wide (maxobjsize, szprec), prod))
1464 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1465 "%Kproduct %<%E * %E%> of arguments %i and %i "
1466 "exceeds maximum object size %E",
1467 exp, argrange[0][0], argrange[1][0],
1468 idx[0] + 1, idx[1] + 1,
1469 maxobjsize);
1470
1471 if (warned)
1472 {
1473 /* Print the full range of each of the two arguments to make
1474 it clear when it is, in fact, in a range and not constant. */
1475 if (argrange[0][0] != argrange [0][1])
1476 inform (loc, "argument %i in the range [%E, %E]",
1477 idx[0] + 1, argrange[0][0], argrange[0][1]);
1478 if (argrange[1][0] != argrange [1][1])
1479 inform (loc, "argument %i in the range [%E, %E]",
1480 idx[1] + 1, argrange[1][0], argrange[1][1]);
1481 }
1482 }
1483
1484 if (warned)
1485 {
1486 location_t fnloc = DECL_SOURCE_LOCATION (fn);
1487
1488 if (DECL_IS_BUILTIN (fn))
1489 inform (loc,
1490 "in a call to built-in allocation function %qD", fn);
1491 else
1492 inform (fnloc,
1493 "in a call to allocation function %qD declared here", fn);
1494 }
1495}
1496
1497/* If EXPR refers to a character array or pointer declared attribute
1498 nonstring return a decl for that array or pointer and set *REF to
1499 the referenced enclosing object or pointer. Otherwise returns
1500 null. */
1501
1502tree
1503get_attr_nonstring_decl (tree expr, tree *ref)
1504{
1505 tree decl = expr;
1506 if (TREE_CODE (decl) == SSA_NAME)
1507 {
1508 gimple *def = SSA_NAME_DEF_STMT (decl);
1509
1510 if (is_gimple_assign (def))
1511 {
1512 tree_code code = gimple_assign_rhs_code (def);
1513 if (code == ADDR_EXPR
1514 || code == COMPONENT_REF
1515 || code == VAR_DECL)
1516 decl = gimple_assign_rhs1 (def);
1517 }
1518 else if (tree var = SSA_NAME_VAR (decl))
1519 decl = var;
1520 }
1521
1522 if (TREE_CODE (decl) == ADDR_EXPR)
1523 decl = TREE_OPERAND (decl, 0);
1524
1525 if (ref)
1526 *ref = decl;
1527
1528 if (TREE_CODE (decl) == COMPONENT_REF)
1529 decl = TREE_OPERAND (decl, 1);
1530
1531 if (DECL_P (decl)
1532 && lookup_attribute ("nonstring", DECL_ATTRIBUTES (decl)))
1533 return decl;
1534
1535 return NULL_TREE;
1536}
1537
1538/* Warn about passing a non-string array/pointer to a function that
1539 expects a nul-terminated string argument. */
1540
1541void
1542maybe_warn_nonstring_arg (tree fndecl, tree exp)
1543{
1544 if (!fndecl || DECL_BUILT_IN_CLASS (fndecl) != BUILT_IN_NORMAL)
1545 return;
1546
1547 bool with_bounds = CALL_WITH_BOUNDS_P (exp);
1548
1549 /* The bound argument to a bounded string function like strncpy. */
1550 tree bound = NULL_TREE;
1551
1552 /* It's safe to call "bounded" string functions with a non-string
1553 argument since the functions provide an explicit bound for this
1554 purpose. */
1555 switch (DECL_FUNCTION_CODE (fndecl))
1556 {
1557 case BUILT_IN_STPNCPY:
1558 case BUILT_IN_STPNCPY_CHK:
1559 case BUILT_IN_STRNCMP:
1560 case BUILT_IN_STRNCASECMP:
1561 case BUILT_IN_STRNCPY:
1562 case BUILT_IN_STRNCPY_CHK:
1563 bound = CALL_EXPR_ARG (exp, with_bounds ? 4 : 2);
1564 break;
1565
1566 case BUILT_IN_STRNDUP:
1567 bound = CALL_EXPR_ARG (exp, with_bounds ? 2 : 1);
1568 break;
1569
1570 default:
1571 break;
1572 }
1573
1574 /* Determine the range of the bound argument (if specified). */
1575 tree bndrng[2] = { NULL_TREE, NULL_TREE };
1576 if (bound)
1577 get_size_range (bound, bndrng);
1578
1579 /* Iterate over the built-in function's formal arguments and check
1580 each const char* against the actual argument. If the actual
1581 argument is declared attribute non-string issue a warning unless
1582 the argument's maximum length is bounded. */
1583 function_args_iterator it;
1584 function_args_iter_init (&it, TREE_TYPE (fndecl));
1585
1586 for (unsigned argno = 0; ; ++argno, function_args_iter_next (&it))
1587 {
1588 tree argtype = function_args_iter_cond (&it);
1589 if (!argtype)
1590 break;
1591
1592 if (TREE_CODE (argtype) != POINTER_TYPE)
1593 continue;
1594
1595 argtype = TREE_TYPE (argtype);
1596
1597 if (TREE_CODE (argtype) != INTEGER_TYPE
1598 || !TYPE_READONLY (argtype))
1599 continue;
1600
1601 argtype = TYPE_MAIN_VARIANT (argtype);
1602 if (argtype != char_type_node)
1603 continue;
1604
1605 tree callarg = CALL_EXPR_ARG (exp, argno);
1606 if (TREE_CODE (callarg) == ADDR_EXPR)
1607 callarg = TREE_OPERAND (callarg, 0);
1608
1609 /* See if the destination is declared with attribute "nonstring". */
1610 tree decl = get_attr_nonstring_decl (callarg);
1611 if (!decl)
1612 continue;
1613
1614 tree type = TREE_TYPE (decl);
1615
1616 offset_int wibnd = 0;
1617 if (bndrng[0])
1618 wibnd = wi::to_offset (bndrng[0]);
1619
1620 offset_int asize = wibnd;
1621
1622 if (TREE_CODE (type) == ARRAY_TYPE)
1623 if (tree arrbnd = TYPE_DOMAIN (type))
1624 {
1625 if ((arrbnd = TYPE_MAX_VALUE (arrbnd)))
1626 asize = wi::to_offset (arrbnd) + 1;
1627 }
1628
1629 location_t loc = EXPR_LOCATION (exp);
1630
1631 bool warned = false;
1632
1633 if (wi::ltu_p (asize, wibnd))
1634 warned = warning_at (loc, OPT_Wstringop_overflow_,
1635 "%qD argument %i declared attribute %<nonstring%> "
1636 "is smaller than the specified bound %E",
1637 fndecl, argno + 1, bndrng[0]);
1638 else if (!bound)
1639 warned = warning_at (loc, OPT_Wstringop_overflow_,
1640 "%qD argument %i declared attribute %<nonstring%>",
1641 fndecl, argno + 1);
1642
1643 if (warned)
1644 inform (DECL_SOURCE_LOCATION (decl),
1645 "argument %qD declared here", decl);
1646 }
1647}
1648
1649/* Issue an error if CALL_EXPR was flagged as requiring
1650 tall-call optimization. */
1651
1652static void
1653maybe_complain_about_tail_call (tree call_expr, const char *reason)
1654{
1655 gcc_assert (TREE_CODE (call_expr) == CALL_EXPR);
1656 if (!CALL_EXPR_MUST_TAIL_CALL (call_expr))
1657 return;
1658
1659 error_at (EXPR_LOCATION (call_expr), "cannot tail-call: %s", reason);
1660}
1661
1662/* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1663 CALL_EXPR EXP.
1664
1665 NUM_ACTUALS is the total number of parameters.
1666
1667 N_NAMED_ARGS is the total number of named arguments.
1668
1669 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
1670 value, or null.
1671
1672 FNDECL is the tree code for the target of this call (if known)
1673
1674 ARGS_SO_FAR holds state needed by the target to know where to place
1675 the next argument.
1676
1677 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1678 for arguments which are passed in registers.
1679
1680 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1681 and may be modified by this routine.
1682
1683 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1684 flags which may be modified by this routine.
1685
1686 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
1687 that requires allocation of stack space.
1688
1689 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1690 the thunked-to function. */
1691
1692static void
1693initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
1694 struct arg_data *args,
1695 struct args_size *args_size,
1696 int n_named_args ATTRIBUTE_UNUSED,
1697 tree exp, tree struct_value_addr_value,
1698 tree fndecl, tree fntype,
1699 cumulative_args_t args_so_far,
1700 int reg_parm_stack_space,
1701 rtx *old_stack_level, int *old_pending_adj,
1702 int *must_preallocate, int *ecf_flags,
1703 bool *may_tailcall, bool call_from_thunk_p)
1704{
1705 CUMULATIVE_ARGS *args_so_far_pnt = get_cumulative_args (args_so_far);
1706 location_t loc = EXPR_LOCATION (exp);
1707
1708 /* Count arg position in order args appear. */
1709 int argpos;
1710
1711 int i;
1712
1713 args_size->constant = 0;
1714 args_size->var = 0;
1715
1716 bitmap_obstack_initialize (NULL);
1717
1718 /* In this loop, we consider args in the order they are written.
1719 We fill up ARGS from the back. */
1720
1721 i = num_actuals - 1;
1722 {
1723 int j = i, ptr_arg = -1;
1724 call_expr_arg_iterator iter;
1725 tree arg;
1726 bitmap slots = NULL;
1727
1728 if (struct_value_addr_value)
1729 {
1730 args[j].tree_value = struct_value_addr_value;
1731 j--;
1732
1733 /* If we pass structure address then we need to
1734 create bounds for it. Since created bounds is
1735 a call statement, we expand it right here to avoid
1736 fixing all other places where it may be expanded. */
1737 if (CALL_WITH_BOUNDS_P (exp))
1738 {
1739 args[j].value = gen_reg_rtx (targetm.chkp_bound_mode ());
1740 args[j].tree_value
1741 = chkp_make_bounds_for_struct_addr (struct_value_addr_value);
1742 expand_expr_real (args[j].tree_value, args[j].value, VOIDmode,
1743 EXPAND_NORMAL, 0, false);
1744 args[j].pointer_arg = j + 1;
1745 j--;
1746 }
1747 }
1748 argpos = 0;
1749 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
1750 {
1751 tree argtype = TREE_TYPE (arg);
1752
1753 /* Remember last param with pointer and associate it
1754 with following pointer bounds. */
1755 if (CALL_WITH_BOUNDS_P (exp)
1756 && chkp_type_has_pointer (argtype))
1757 {
1758 if (slots)
1759 BITMAP_FREE (slots);
1760 ptr_arg = j;
1761 if (!BOUNDED_TYPE_P (argtype))
1762 {
1763 slots = BITMAP_ALLOC (NULL);
1764 chkp_find_bound_slots (argtype, slots);
1765 }
1766 }
1767 else if (CALL_WITH_BOUNDS_P (exp)
1768 && pass_by_reference (NULL, TYPE_MODE (argtype), argtype,
1769 argpos < n_named_args))
1770 {
1771 if (slots)
1772 BITMAP_FREE (slots);
1773 ptr_arg = j;
1774 }
1775 else if (POINTER_BOUNDS_TYPE_P (argtype))
1776 {
1777 /* We expect bounds in instrumented calls only.
1778 Otherwise it is a sign we lost flag due to some optimization
1779 and may emit call args incorrectly. */
1780 gcc_assert (CALL_WITH_BOUNDS_P (exp));
1781
1782 /* For structures look for the next available pointer. */
1783 if (ptr_arg != -1 && slots)
1784 {
1785 unsigned bnd_no = bitmap_first_set_bit (slots);
1786 args[j].pointer_offset =
1787 bnd_no * POINTER_SIZE / BITS_PER_UNIT;
1788
1789 bitmap_clear_bit (slots, bnd_no);
1790
1791 /* Check we have no more pointers in the structure. */
1792 if (bitmap_empty_p (slots))
1793 BITMAP_FREE (slots);
1794 }
1795 args[j].pointer_arg = ptr_arg;
1796
1797 /* Check we covered all pointers in the previous
1798 non bounds arg. */
1799 if (!slots)
1800 ptr_arg = -1;
1801 }
1802 else
1803 ptr_arg = -1;
1804
1805 if (targetm.calls.split_complex_arg
1806 && argtype
1807 && TREE_CODE (argtype) == COMPLEX_TYPE
1808 && targetm.calls.split_complex_arg (argtype))
1809 {
1810 tree subtype = TREE_TYPE (argtype);
1811 args[j].tree_value = build1 (REALPART_EXPR, subtype, arg);
1812 j--;
1813 args[j].tree_value = build1 (IMAGPART_EXPR, subtype, arg);
1814 }
1815 else
1816 args[j].tree_value = arg;
1817 j--;
1818 argpos++;
1819 }
1820
1821 if (slots)
1822 BITMAP_FREE (slots);
1823 }
1824
1825 bitmap_obstack_release (NULL);
1826
1827 /* Extract attribute alloc_size and if set, store the indices of
1828 the corresponding arguments in ALLOC_IDX, and then the actual
1829 argument(s) at those indices in ALLOC_ARGS. */
1830 int alloc_idx[2] = { -1, -1 };
1831 if (tree alloc_size
1832 = (fndecl ? lookup_attribute ("alloc_size",
1833 TYPE_ATTRIBUTES (TREE_TYPE (fndecl)))
1834 : NULL_TREE))
1835 {
1836 tree args = TREE_VALUE (alloc_size);
1837 alloc_idx[0] = TREE_INT_CST_LOW (TREE_VALUE (args)) - 1;
1838 if (TREE_CHAIN (args))
1839 alloc_idx[1] = TREE_INT_CST_LOW (TREE_VALUE (TREE_CHAIN (args))) - 1;
1840 }
1841
1842 /* Array for up to the two attribute alloc_size arguments. */
1843 tree alloc_args[] = { NULL_TREE, NULL_TREE };
1844
1845 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1846 for (argpos = 0; argpos < num_actuals; i--, argpos++)
1847 {
1848 tree type = TREE_TYPE (args[i].tree_value);
1849 int unsignedp;
1850 machine_mode mode;
1851
1852 /* Replace erroneous argument with constant zero. */
1853 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1854 args[i].tree_value = integer_zero_node, type = integer_type_node;
1855
1856 /* If TYPE is a transparent union or record, pass things the way
1857 we would pass the first field of the union or record. We have
1858 already verified that the modes are the same. */
1859 if ((TREE_CODE (type) == UNION_TYPE || TREE_CODE (type) == RECORD_TYPE)
1860 && TYPE_TRANSPARENT_AGGR (type))
1861 type = TREE_TYPE (first_field (type));
1862
1863 /* Decide where to pass this arg.
1864
1865 args[i].reg is nonzero if all or part is passed in registers.
1866
1867 args[i].partial is nonzero if part but not all is passed in registers,
1868 and the exact value says how many bytes are passed in registers.
1869
1870 args[i].pass_on_stack is nonzero if the argument must at least be
1871 computed on the stack. It may then be loaded back into registers
1872 if args[i].reg is nonzero.
1873
1874 These decisions are driven by the FUNCTION_... macros and must agree
1875 with those made by function.c. */
1876
1877 /* See if this argument should be passed by invisible reference. */
1878 if (pass_by_reference (args_so_far_pnt, TYPE_MODE (type),
1879 type, argpos < n_named_args))
1880 {
1881 bool callee_copies;
1882 tree base = NULL_TREE;
1883
1884 callee_copies
1885 = reference_callee_copied (args_so_far_pnt, TYPE_MODE (type),
1886 type, argpos < n_named_args);
1887
1888 /* If we're compiling a thunk, pass through invisible references
1889 instead of making a copy. */
1890 if (call_from_thunk_p
1891 || (callee_copies
1892 && !TREE_ADDRESSABLE (type)
1893 && (base = get_base_address (args[i].tree_value))
1894 && TREE_CODE (base) != SSA_NAME
1895 && (!DECL_P (base) || MEM_P (DECL_RTL (base)))))
1896 {
1897 /* We may have turned the parameter value into an SSA name.
1898 Go back to the original parameter so we can take the
1899 address. */
1900 if (TREE_CODE (args[i].tree_value) == SSA_NAME)
1901 {
1902 gcc_assert (SSA_NAME_IS_DEFAULT_DEF (args[i].tree_value));
1903 args[i].tree_value = SSA_NAME_VAR (args[i].tree_value);
1904 gcc_assert (TREE_CODE (args[i].tree_value) == PARM_DECL);
1905 }
1906 /* Argument setup code may have copied the value to register. We
1907 revert that optimization now because the tail call code must
1908 use the original location. */
1909 if (TREE_CODE (args[i].tree_value) == PARM_DECL
1910 && !MEM_P (DECL_RTL (args[i].tree_value))
1911 && DECL_INCOMING_RTL (args[i].tree_value)
1912 && MEM_P (DECL_INCOMING_RTL (args[i].tree_value)))
1913 set_decl_rtl (args[i].tree_value,
1914 DECL_INCOMING_RTL (args[i].tree_value));
1915
1916 mark_addressable (args[i].tree_value);
1917
1918 /* We can't use sibcalls if a callee-copied argument is
1919 stored in the current function's frame. */
1920 if (!call_from_thunk_p && DECL_P (base) && !TREE_STATIC (base))
1921 {
1922 *may_tailcall = false;
1923 maybe_complain_about_tail_call (exp,
1924 "a callee-copied argument is"
1925 " stored in the current "
1926 " function's frame");
1927 }
1928
1929 args[i].tree_value = build_fold_addr_expr_loc (loc,
1930 args[i].tree_value);
1931 type = TREE_TYPE (args[i].tree_value);
1932
1933 if (*ecf_flags & ECF_CONST)
1934 *ecf_flags &= ~(ECF_CONST | ECF_LOOPING_CONST_OR_PURE);
1935 }
1936 else
1937 {
1938 /* We make a copy of the object and pass the address to the
1939 function being called. */
1940 rtx copy;
1941
1942 if (!COMPLETE_TYPE_P (type)
1943 || TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST
1944 || (flag_stack_check == GENERIC_STACK_CHECK
1945 && compare_tree_int (TYPE_SIZE_UNIT (type),
1946 STACK_CHECK_MAX_VAR_SIZE) > 0))
1947 {
1948 /* This is a variable-sized object. Make space on the stack
1949 for it. */
1950 rtx size_rtx = expr_size (args[i].tree_value);
1951
1952 if (*old_stack_level == 0)
1953 {
1954 emit_stack_save (SAVE_BLOCK, old_stack_level);
1955 *old_pending_adj = pending_stack_adjust;
1956 pending_stack_adjust = 0;
1957 }
1958
1959 /* We can pass TRUE as the 4th argument because we just
1960 saved the stack pointer and will restore it right after
1961 the call. */
1962 copy = allocate_dynamic_stack_space (size_rtx,
1963 TYPE_ALIGN (type),
1964 TYPE_ALIGN (type),
1965 max_int_size_in_bytes
1966 (type),
1967 true);
1968 copy = gen_rtx_MEM (BLKmode, copy);
1969 set_mem_attributes (copy, type, 1);
1970 }
1971 else
1972 copy = assign_temp (type, 1, 0);
1973
1974 store_expr (args[i].tree_value, copy, 0, false, false);
1975
1976 /* Just change the const function to pure and then let
1977 the next test clear the pure based on
1978 callee_copies. */
1979 if (*ecf_flags & ECF_CONST)
1980 {
1981 *ecf_flags &= ~ECF_CONST;
1982 *ecf_flags |= ECF_PURE;
1983 }
1984
1985 if (!callee_copies && *ecf_flags & ECF_PURE)
1986 *ecf_flags &= ~(ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
1987
1988 args[i].tree_value
1989 = build_fold_addr_expr_loc (loc, make_tree (type, copy));
1990 type = TREE_TYPE (args[i].tree_value);
1991 *may_tailcall = false;
1992 maybe_complain_about_tail_call (exp,
1993 "argument must be passed"
1994 " by copying");
1995 }
1996 }
1997
1998 unsignedp = TYPE_UNSIGNED (type);
1999 mode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
2000 fndecl ? TREE_TYPE (fndecl) : fntype, 0);
2001
2002 args[i].unsignedp = unsignedp;
2003 args[i].mode = mode;
2004
2005 targetm.calls.warn_parameter_passing_abi (args_so_far, type);
2006
2007 args[i].reg = targetm.calls.function_arg (args_so_far, mode, type,
2008 argpos < n_named_args);
2009
2010 if (args[i].reg && CONST_INT_P (args[i].reg))
2011 {
2012 args[i].special_slot = args[i].reg;
2013 args[i].reg = NULL;
2014 }
2015
2016 /* If this is a sibling call and the machine has register windows, the
2017 register window has to be unwinded before calling the routine, so
2018 arguments have to go into the incoming registers. */
2019 if (targetm.calls.function_incoming_arg != targetm.calls.function_arg)
2020 args[i].tail_call_reg
2021 = targetm.calls.function_incoming_arg (args_so_far, mode, type,
2022 argpos < n_named_args);
2023 else
2024 args[i].tail_call_reg = args[i].reg;
2025
2026 if (args[i].reg)
2027 args[i].partial
2028 = targetm.calls.arg_partial_bytes (args_so_far, mode, type,
2029 argpos < n_named_args);
2030
2031 args[i].pass_on_stack = targetm.calls.must_pass_in_stack (mode, type);
2032
2033 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
2034 it means that we are to pass this arg in the register(s) designated
2035 by the PARALLEL, but also to pass it in the stack. */
2036 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
2037 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
2038 args[i].pass_on_stack = 1;
2039
2040 /* If this is an addressable type, we must preallocate the stack
2041 since we must evaluate the object into its final location.
2042
2043 If this is to be passed in both registers and the stack, it is simpler
2044 to preallocate. */
2045 if (TREE_ADDRESSABLE (type)
2046 || (args[i].pass_on_stack && args[i].reg != 0))
2047 *must_preallocate = 1;
2048
2049 /* No stack allocation and padding for bounds. */
2050 if (POINTER_BOUNDS_P (args[i].tree_value))
2051 ;
2052 /* Compute the stack-size of this argument. */
2053 else if (args[i].reg == 0 || args[i].partial != 0
2054 || reg_parm_stack_space > 0
2055 || args[i].pass_on_stack)
2056 locate_and_pad_parm (mode, type,
2057#ifdef STACK_PARMS_IN_REG_PARM_AREA
2058 1,
2059#else
2060 args[i].reg != 0,
2061#endif
2062 reg_parm_stack_space,
2063 args[i].pass_on_stack ? 0 : args[i].partial,
2064 fndecl, args_size, &args[i].locate);
2065#ifdef BLOCK_REG_PADDING
2066 else
2067 /* The argument is passed entirely in registers. See at which
2068 end it should be padded. */
2069 args[i].locate.where_pad =
2070 BLOCK_REG_PADDING (mode, type,
2071 int_size_in_bytes (type) <= UNITS_PER_WORD);
2072#endif
2073
2074 /* Update ARGS_SIZE, the total stack space for args so far. */
2075
2076 args_size->constant += args[i].locate.size.constant;
2077 if (args[i].locate.size.var)
2078 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
2079
2080 /* Increment ARGS_SO_FAR, which has info about which arg-registers
2081 have been used, etc. */
2082
2083 targetm.calls.function_arg_advance (args_so_far, TYPE_MODE (type),
2084 type, argpos < n_named_args);
2085
2086 /* Store argument values for functions decorated with attribute
2087 alloc_size. */
2088 if (argpos == alloc_idx[0])
2089 alloc_args[0] = args[i].tree_value;
2090 else if (argpos == alloc_idx[1])
2091 alloc_args[1] = args[i].tree_value;
2092 }
2093
2094 if (alloc_args[0])
2095 {
2096 /* Check the arguments of functions decorated with attribute
2097 alloc_size. */
2098 maybe_warn_alloc_args_overflow (fndecl, exp, alloc_args, alloc_idx);
2099 }
2100
2101 /* Detect passing non-string arguments to functions expecting
2102 nul-terminated strings. */
2103 maybe_warn_nonstring_arg (fndecl, exp);
2104}
2105
2106/* Update ARGS_SIZE to contain the total size for the argument block.
2107 Return the original constant component of the argument block's size.
2108
2109 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
2110 for arguments passed in registers. */
2111
2112static int
2113compute_argument_block_size (int reg_parm_stack_space,
2114 struct args_size *args_size,
2115 tree fndecl ATTRIBUTE_UNUSED,
2116 tree fntype ATTRIBUTE_UNUSED,
2117 int preferred_stack_boundary ATTRIBUTE_UNUSED)
2118{
2119 int unadjusted_args_size = args_size->constant;
2120
2121 /* For accumulate outgoing args mode we don't need to align, since the frame
2122 will be already aligned. Align to STACK_BOUNDARY in order to prevent
2123 backends from generating misaligned frame sizes. */
2124 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
2125 preferred_stack_boundary = STACK_BOUNDARY;
2126
2127 /* Compute the actual size of the argument block required. The variable
2128 and constant sizes must be combined, the size may have to be rounded,
2129 and there may be a minimum required size. */
2130
2131 if (args_size->var)
2132 {
2133 args_size->var = ARGS_SIZE_TREE (*args_size);
2134 args_size->constant = 0;
2135
2136 preferred_stack_boundary /= BITS_PER_UNIT;
2137 if (preferred_stack_boundary > 1)
2138 {
2139 /* We don't handle this case yet. To handle it correctly we have
2140 to add the delta, round and subtract the delta.
2141 Currently no machine description requires this support. */
2142 gcc_assert (!(stack_pointer_delta & (preferred_stack_boundary - 1)));
2143 args_size->var = round_up (args_size->var, preferred_stack_boundary);
2144 }
2145
2146 if (reg_parm_stack_space > 0)
2147 {
2148 args_size->var
2149 = size_binop (MAX_EXPR, args_size->var,
2150 ssize_int (reg_parm_stack_space));
2151
2152 /* The area corresponding to register parameters is not to count in
2153 the size of the block we need. So make the adjustment. */
2154 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
2155 args_size->var
2156 = size_binop (MINUS_EXPR, args_size->var,
2157 ssize_int (reg_parm_stack_space));
2158 }
2159 }
2160 else
2161 {
2162 preferred_stack_boundary /= BITS_PER_UNIT;
2163 if (preferred_stack_boundary < 1)
2164 preferred_stack_boundary = 1;
2165 args_size->constant = (((args_size->constant
2166 + stack_pointer_delta
2167 + preferred_stack_boundary - 1)
2168 / preferred_stack_boundary
2169 * preferred_stack_boundary)
2170 - stack_pointer_delta);
2171
2172 args_size->constant = MAX (args_size->constant,
2173 reg_parm_stack_space);
2174
2175 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
2176 args_size->constant -= reg_parm_stack_space;
2177 }
2178 return unadjusted_args_size;
2179}
2180
2181/* Precompute parameters as needed for a function call.
2182
2183 FLAGS is mask of ECF_* constants.
2184
2185 NUM_ACTUALS is the number of arguments.
2186
2187 ARGS is an array containing information for each argument; this
2188 routine fills in the INITIAL_VALUE and VALUE fields for each
2189 precomputed argument. */
2190
2191static void
2192precompute_arguments (int num_actuals, struct arg_data *args)
2193{
2194 int i;
2195
2196 /* If this is a libcall, then precompute all arguments so that we do not
2197 get extraneous instructions emitted as part of the libcall sequence. */
2198
2199 /* If we preallocated the stack space, and some arguments must be passed
2200 on the stack, then we must precompute any parameter which contains a
2201 function call which will store arguments on the stack.
2202 Otherwise, evaluating the parameter may clobber previous parameters
2203 which have already been stored into the stack. (we have code to avoid
2204 such case by saving the outgoing stack arguments, but it results in
2205 worse code) */
2206 if (!ACCUMULATE_OUTGOING_ARGS)
2207 return;
2208
2209 for (i = 0; i < num_actuals; i++)
2210 {
2211 tree type;
2212 machine_mode mode;
2213
2214 if (TREE_CODE (args[i].tree_value) != CALL_EXPR)
2215 continue;
2216
2217 /* If this is an addressable type, we cannot pre-evaluate it. */
2218 type = TREE_TYPE (args[i].tree_value);
2219 gcc_assert (!TREE_ADDRESSABLE (type));
2220
2221 args[i].initial_value = args[i].value
2222 = expand_normal (args[i].tree_value);
2223
2224 mode = TYPE_MODE (type);
2225 if (mode != args[i].mode)
2226 {
2227 int unsignedp = args[i].unsignedp;
2228 args[i].value
2229 = convert_modes (args[i].mode, mode,
2230 args[i].value, args[i].unsignedp);
2231
2232 /* CSE will replace this only if it contains args[i].value
2233 pseudo, so convert it down to the declared mode using
2234 a SUBREG. */
2235 if (REG_P (args[i].value)
2236 && GET_MODE_CLASS (args[i].mode) == MODE_INT
2237 && promote_mode (type, mode, &unsignedp) != args[i].mode)
2238 {
2239 args[i].initial_value
2240 = gen_lowpart_SUBREG (mode, args[i].value);
2241 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
2242 SUBREG_PROMOTED_SET (args[i].initial_value, args[i].unsignedp);
2243 }
2244 }
2245 }
2246}
2247
2248/* Given the current state of MUST_PREALLOCATE and information about
2249 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
2250 compute and return the final value for MUST_PREALLOCATE. */
2251
2252static int
2253finalize_must_preallocate (int must_preallocate, int num_actuals,
2254 struct arg_data *args, struct args_size *args_size)
2255{
2256 /* See if we have or want to preallocate stack space.
2257
2258 If we would have to push a partially-in-regs parm
2259 before other stack parms, preallocate stack space instead.
2260
2261 If the size of some parm is not a multiple of the required stack
2262 alignment, we must preallocate.
2263
2264 If the total size of arguments that would otherwise create a copy in
2265 a temporary (such as a CALL) is more than half the total argument list
2266 size, preallocation is faster.
2267
2268 Another reason to preallocate is if we have a machine (like the m88k)
2269 where stack alignment is required to be maintained between every
2270 pair of insns, not just when the call is made. However, we assume here
2271 that such machines either do not have push insns (and hence preallocation
2272 would occur anyway) or the problem is taken care of with
2273 PUSH_ROUNDING. */
2274
2275 if (! must_preallocate)
2276 {
2277 int partial_seen = 0;
2278 int copy_to_evaluate_size = 0;
2279 int i;
2280
2281 for (i = 0; i < num_actuals && ! must_preallocate; i++)
2282 {
2283 if (args[i].partial > 0 && ! args[i].pass_on_stack)
2284 partial_seen = 1;
2285 else if (partial_seen && args[i].reg == 0)
2286 must_preallocate = 1;
2287 /* We preallocate in case there are bounds passed
2288 in the bounds table to have precomputed address
2289 for bounds association. */
2290 else if (POINTER_BOUNDS_P (args[i].tree_value)
2291 && !args[i].reg)
2292 must_preallocate = 1;
2293
2294 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
2295 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
2296 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
2297 || TREE_CODE (args[i].tree_value) == COND_EXPR
2298 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
2299 copy_to_evaluate_size
2300 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
2301 }
2302
2303 if (copy_to_evaluate_size * 2 >= args_size->constant
2304 && args_size->constant > 0)
2305 must_preallocate = 1;
2306 }
2307 return must_preallocate;
2308}
2309
2310/* If we preallocated stack space, compute the address of each argument
2311 and store it into the ARGS array.
2312
2313 We need not ensure it is a valid memory address here; it will be
2314 validized when it is used.
2315
2316 ARGBLOCK is an rtx for the address of the outgoing arguments. */
2317
2318static void
2319compute_argument_addresses (struct arg_data *args, rtx argblock, int num_actuals)
2320{
2321 if (argblock)
2322 {
2323 rtx arg_reg = argblock;
2324 int i, arg_offset = 0;
2325
2326 if (GET_CODE (argblock) == PLUS)
2327 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
2328
2329 for (i = 0; i < num_actuals; i++)
2330 {
2331 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
2332 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
2333 rtx addr;
2334 unsigned int align, boundary;
2335 unsigned int units_on_stack = 0;
2336 machine_mode partial_mode = VOIDmode;
2337
2338 /* Skip this parm if it will not be passed on the stack. */
2339 if (! args[i].pass_on_stack
2340 && args[i].reg != 0
2341 && args[i].partial == 0)
2342 continue;
2343
2344 /* Pointer Bounds are never passed on the stack. */
2345 if (POINTER_BOUNDS_P (args[i].tree_value))
2346 continue;
2347
2348 addr = simplify_gen_binary (PLUS, Pmode, arg_reg, offset);
2349 addr = plus_constant (Pmode, addr, arg_offset);
2350
2351 if (args[i].partial != 0)
2352 {
2353 /* Only part of the parameter is being passed on the stack.
2354 Generate a simple memory reference of the correct size. */
2355 units_on_stack = args[i].locate.size.constant;
2356 unsigned int bits_on_stack = units_on_stack * BITS_PER_UNIT;
2357 partial_mode = int_mode_for_size (bits_on_stack, 1).else_blk ();
2358 args[i].stack = gen_rtx_MEM (partial_mode, addr);
2359 set_mem_size (args[i].stack, units_on_stack);
2360 }
2361 else
2362 {
2363 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
2364 set_mem_attributes (args[i].stack,
2365 TREE_TYPE (args[i].tree_value), 1);
2366 }
2367 align = BITS_PER_UNIT;
2368 boundary = args[i].locate.boundary;
2369 if (args[i].locate.where_pad != PAD_DOWNWARD)
2370 align = boundary;
2371 else if (CONST_INT_P (offset))
2372 {
2373 align = INTVAL (offset) * BITS_PER_UNIT | boundary;
2374 align = least_bit_hwi (align);
2375 }
2376 set_mem_align (args[i].stack, align);
2377
2378 addr = simplify_gen_binary (PLUS, Pmode, arg_reg, slot_offset);
2379 addr = plus_constant (Pmode, addr, arg_offset);
2380
2381 if (args[i].partial != 0)
2382 {
2383 /* Only part of the parameter is being passed on the stack.
2384 Generate a simple memory reference of the correct size.
2385 */
2386 args[i].stack_slot = gen_rtx_MEM (partial_mode, addr);
2387 set_mem_size (args[i].stack_slot, units_on_stack);
2388 }
2389 else
2390 {
2391 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
2392 set_mem_attributes (args[i].stack_slot,
2393 TREE_TYPE (args[i].tree_value), 1);
2394 }
2395 set_mem_align (args[i].stack_slot, args[i].locate.boundary);
2396
2397 /* Function incoming arguments may overlap with sibling call
2398 outgoing arguments and we cannot allow reordering of reads
2399 from function arguments with stores to outgoing arguments
2400 of sibling calls. */
2401 set_mem_alias_set (args[i].stack, 0);
2402 set_mem_alias_set (args[i].stack_slot, 0);
2403 }
2404 }
2405}
2406
2407/* Given a FNDECL and EXP, return an rtx suitable for use as a target address
2408 in a call instruction.
2409
2410 FNDECL is the tree node for the target function. For an indirect call
2411 FNDECL will be NULL_TREE.
2412
2413 ADDR is the operand 0 of CALL_EXPR for this call. */
2414
2415static rtx
2416rtx_for_function_call (tree fndecl, tree addr)
2417{
2418 rtx funexp;
2419
2420 /* Get the function to call, in the form of RTL. */
2421 if (fndecl)
2422 {
2423 if (!TREE_USED (fndecl) && fndecl != current_function_decl)
2424 TREE_USED (fndecl) = 1;
2425
2426 /* Get a SYMBOL_REF rtx for the function address. */
2427 funexp = XEXP (DECL_RTL (fndecl), 0);
2428 }
2429 else
2430 /* Generate an rtx (probably a pseudo-register) for the address. */
2431 {
2432 push_temp_slots ();
2433 funexp = expand_normal (addr);
2434 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
2435 }
2436 return funexp;
2437}
2438
2439/* Internal state for internal_arg_pointer_based_exp and its helpers. */
2440static struct
2441{
2442 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
2443 or NULL_RTX if none has been scanned yet. */
2444 rtx_insn *scan_start;
2445 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
2446 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
2447 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
2448 with fixed offset, or PC if this is with variable or unknown offset. */
2449 vec<rtx> cache;
2450} internal_arg_pointer_exp_state;
2451
2452static rtx internal_arg_pointer_based_exp (const_rtx, bool);
2453
2454/* Helper function for internal_arg_pointer_based_exp. Scan insns in
2455 the tail call sequence, starting with first insn that hasn't been
2456 scanned yet, and note for each pseudo on the LHS whether it is based
2457 on crtl->args.internal_arg_pointer or not, and what offset from that
2458 that pointer it has. */
2459
2460static void
2461internal_arg_pointer_based_exp_scan (void)
2462{
2463 rtx_insn *insn, *scan_start = internal_arg_pointer_exp_state.scan_start;
2464
2465 if (scan_start == NULL_RTX)
2466 insn = get_insns ();
2467 else
2468 insn = NEXT_INSN (scan_start);
2469
2470 while (insn)
2471 {
2472 rtx set = single_set (insn);
2473 if (set && REG_P (SET_DEST (set)) && !HARD_REGISTER_P (SET_DEST (set)))
2474 {
2475 rtx val = NULL_RTX;
2476 unsigned int idx = REGNO (SET_DEST (set)) - FIRST_PSEUDO_REGISTER;
2477 /* Punt on pseudos set multiple times. */
2478 if (idx < internal_arg_pointer_exp_state.cache.length ()
2479 && (internal_arg_pointer_exp_state.cache[idx]
2480 != NULL_RTX))
2481 val = pc_rtx;
2482 else
2483 val = internal_arg_pointer_based_exp (SET_SRC (set), false);
2484 if (val != NULL_RTX)
2485 {
2486 if (idx >= internal_arg_pointer_exp_state.cache.length ())
2487 internal_arg_pointer_exp_state.cache
2488 .safe_grow_cleared (idx + 1);
2489 internal_arg_pointer_exp_state.cache[idx] = val;
2490 }
2491 }
2492 if (NEXT_INSN (insn) == NULL_RTX)
2493 scan_start = insn;
2494 insn = NEXT_INSN (insn);
2495 }
2496
2497 internal_arg_pointer_exp_state.scan_start = scan_start;
2498}
2499
2500/* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
2501 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
2502 it with fixed offset, or PC if this is with variable or unknown offset.
2503 TOPLEVEL is true if the function is invoked at the topmost level. */
2504
2505static rtx
2506internal_arg_pointer_based_exp (const_rtx rtl, bool toplevel)
2507{
2508 if (CONSTANT_P (rtl))
2509 return NULL_RTX;
2510
2511 if (rtl == crtl->args.internal_arg_pointer)
2512 return const0_rtx;
2513
2514 if (REG_P (rtl) && HARD_REGISTER_P (rtl))
2515 return NULL_RTX;
2516
2517 if (GET_CODE (rtl) == PLUS && CONST_INT_P (XEXP (rtl, 1)))
2518 {
2519 rtx val = internal_arg_pointer_based_exp (XEXP (rtl, 0), toplevel);
2520 if (val == NULL_RTX || val == pc_rtx)
2521 return val;
2522 return plus_constant (Pmode, val, INTVAL (XEXP (rtl, 1)));
2523 }
2524
2525 /* When called at the topmost level, scan pseudo assignments in between the
2526 last scanned instruction in the tail call sequence and the latest insn
2527 in that sequence. */
2528 if (toplevel)
2529 internal_arg_pointer_based_exp_scan ();
2530
2531 if (REG_P (rtl))
2532 {
2533 unsigned int idx = REGNO (rtl) - FIRST_PSEUDO_REGISTER;
2534 if (idx < internal_arg_pointer_exp_state.cache.length ())
2535 return internal_arg_pointer_exp_state.cache[idx];
2536
2537 return NULL_RTX;
2538 }
2539
2540 subrtx_iterator::array_type array;
2541 FOR_EACH_SUBRTX (iter, array, rtl, NONCONST)
2542 {
2543 const_rtx x = *iter;
2544 if (REG_P (x) && internal_arg_pointer_based_exp (x, false) != NULL_RTX)
2545 return pc_rtx;
2546 if (MEM_P (x))
2547 iter.skip_subrtxes ();
2548 }
2549
2550 return NULL_RTX;
2551}
2552
2553/* Return true if and only if SIZE storage units (usually bytes)
2554 starting from address ADDR overlap with already clobbered argument
2555 area. This function is used to determine if we should give up a
2556 sibcall. */
2557
2558static bool
2559mem_overlaps_already_clobbered_arg_p (rtx addr, unsigned HOST_WIDE_INT size)
2560{
2561 HOST_WIDE_INT i;
2562 rtx val;
2563
2564 if (bitmap_empty_p (stored_args_map))
2565 return false;
2566 val = internal_arg_pointer_based_exp (addr, true);
2567 if (val == NULL_RTX)
2568 return false;
2569 else if (val == pc_rtx)
2570 return true;
2571 else
2572 i = INTVAL (val);
2573
2574 if (STACK_GROWS_DOWNWARD)
2575 i -= crtl->args.pretend_args_size;
2576 else
2577 i += crtl->args.pretend_args_size;
2578
2579
2580 if (ARGS_GROW_DOWNWARD)
2581 i = -i - size;
2582
2583 if (size > 0)
2584 {
2585 unsigned HOST_WIDE_INT k;
2586
2587 for (k = 0; k < size; k++)
2588 if (i + k < SBITMAP_SIZE (stored_args_map)
2589 && bitmap_bit_p (stored_args_map, i + k))
2590 return true;
2591 }
2592
2593 return false;
2594}
2595
2596/* Do the register loads required for any wholly-register parms or any
2597 parms which are passed both on the stack and in a register. Their
2598 expressions were already evaluated.
2599
2600 Mark all register-parms as living through the call, putting these USE
2601 insns in the CALL_INSN_FUNCTION_USAGE field.
2602
2603 When IS_SIBCALL, perform the check_sibcall_argument_overlap
2604 checking, setting *SIBCALL_FAILURE if appropriate. */
2605
2606static void
2607load_register_parameters (struct arg_data *args, int num_actuals,
2608 rtx *call_fusage, int flags, int is_sibcall,
2609 int *sibcall_failure)
2610{
2611 int i, j;
2612
2613 for (i = 0; i < num_actuals; i++)
2614 {
2615 rtx reg = ((flags & ECF_SIBCALL)
2616 ? args[i].tail_call_reg : args[i].reg);
2617 if (reg)
2618 {
2619 int partial = args[i].partial;
2620 int nregs;
2621 int size = 0;
2622 rtx_insn *before_arg = get_last_insn ();
2623 /* Set non-negative if we must move a word at a time, even if
2624 just one word (e.g, partial == 4 && mode == DFmode). Set
2625 to -1 if we just use a normal move insn. This value can be
2626 zero if the argument is a zero size structure. */
2627 nregs = -1;
2628 if (GET_CODE (reg) == PARALLEL)
2629 ;
2630 else if (partial)
2631 {
2632 gcc_assert (partial % UNITS_PER_WORD == 0);
2633 nregs = partial / UNITS_PER_WORD;
2634 }
2635 else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
2636 {
2637 size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
2638 nregs = (size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
2639 }
2640 else
2641 size = GET_MODE_SIZE (args[i].mode);
2642
2643 /* Handle calls that pass values in multiple non-contiguous
2644 locations. The Irix 6 ABI has examples of this. */
2645
2646 if (GET_CODE (reg) == PARALLEL)
2647 emit_group_move (reg, args[i].parallel_value);
2648
2649 /* If simple case, just do move. If normal partial, store_one_arg
2650 has already loaded the register for us. In all other cases,
2651 load the register(s) from memory. */
2652
2653 else if (nregs == -1)
2654 {
2655 emit_move_insn (reg, args[i].value);
2656#ifdef BLOCK_REG_PADDING
2657 /* Handle case where we have a value that needs shifting
2658 up to the msb. eg. a QImode value and we're padding
2659 upward on a BYTES_BIG_ENDIAN machine. */
2660 if (size < UNITS_PER_WORD
2661 && (args[i].locate.where_pad
2662 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
2663 {
2664 rtx x;
2665 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2666
2667 /* Assigning REG here rather than a temp makes CALL_FUSAGE
2668 report the whole reg as used. Strictly speaking, the
2669 call only uses SIZE bytes at the msb end, but it doesn't
2670 seem worth generating rtl to say that. */
2671 reg = gen_rtx_REG (word_mode, REGNO (reg));
2672 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
2673 if (x != reg)
2674 emit_move_insn (reg, x);
2675 }
2676#endif
2677 }
2678
2679 /* If we have pre-computed the values to put in the registers in
2680 the case of non-aligned structures, copy them in now. */
2681
2682 else if (args[i].n_aligned_regs != 0)
2683 for (j = 0; j < args[i].n_aligned_regs; j++)
2684 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
2685 args[i].aligned_regs[j]);
2686
2687 else if (partial == 0 || args[i].pass_on_stack)
2688 {
2689 rtx mem = validize_mem (copy_rtx (args[i].value));
2690
2691 /* Check for overlap with already clobbered argument area,
2692 providing that this has non-zero size. */
2693 if (is_sibcall
2694 && size != 0
2695 && (mem_overlaps_already_clobbered_arg_p
2696 (XEXP (args[i].value, 0), size)))
2697 *sibcall_failure = 1;
2698
2699 if (size % UNITS_PER_WORD == 0
2700 || MEM_ALIGN (mem) % BITS_PER_WORD == 0)
2701 move_block_to_reg (REGNO (reg), mem, nregs, args[i].mode);
2702 else
2703 {
2704 if (nregs > 1)
2705 move_block_to_reg (REGNO (reg), mem, nregs - 1,
2706 args[i].mode);
2707 rtx dest = gen_rtx_REG (word_mode, REGNO (reg) + nregs - 1);
2708 unsigned int bitoff = (nregs - 1) * BITS_PER_WORD;
2709 unsigned int bitsize = size * BITS_PER_UNIT - bitoff;
2710 rtx x = extract_bit_field (mem, bitsize, bitoff, 1, dest,
2711 word_mode, word_mode, false,
2712 NULL);
2713 if (BYTES_BIG_ENDIAN)
2714 x = expand_shift (LSHIFT_EXPR, word_mode, x,
2715 BITS_PER_WORD - bitsize, dest, 1);
2716 if (x != dest)
2717 emit_move_insn (dest, x);
2718 }
2719
2720 /* Handle a BLKmode that needs shifting. */
2721 if (nregs == 1 && size < UNITS_PER_WORD
2722#ifdef BLOCK_REG_PADDING
2723 && args[i].locate.where_pad == PAD_DOWNWARD
2724#else
2725 && BYTES_BIG_ENDIAN
2726#endif
2727 )
2728 {
2729 rtx dest = gen_rtx_REG (word_mode, REGNO (reg));
2730 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2731 enum tree_code dir = (BYTES_BIG_ENDIAN
2732 ? RSHIFT_EXPR : LSHIFT_EXPR);
2733 rtx x;
2734
2735 x = expand_shift (dir, word_mode, dest, shift, dest, 1);
2736 if (x != dest)
2737 emit_move_insn (dest, x);
2738 }
2739 }
2740
2741 /* When a parameter is a block, and perhaps in other cases, it is
2742 possible that it did a load from an argument slot that was
2743 already clobbered. */
2744 if (is_sibcall
2745 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
2746 *sibcall_failure = 1;
2747
2748 /* Handle calls that pass values in multiple non-contiguous
2749 locations. The Irix 6 ABI has examples of this. */
2750 if (GET_CODE (reg) == PARALLEL)
2751 use_group_regs (call_fusage, reg);
2752 else if (nregs == -1)
2753 use_reg_mode (call_fusage, reg,
2754 TYPE_MODE (TREE_TYPE (args[i].tree_value)));
2755 else if (nregs > 0)
2756 use_regs (call_fusage, REGNO (reg), nregs);
2757 }
2758 }
2759}
2760
2761/* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
2762 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
2763 bytes, then we would need to push some additional bytes to pad the
2764 arguments. So, we compute an adjust to the stack pointer for an
2765 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
2766 bytes. Then, when the arguments are pushed the stack will be perfectly
2767 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
2768 be popped after the call. Returns the adjustment. */
2769
2770static int
2771combine_pending_stack_adjustment_and_call (int unadjusted_args_size,
2772 struct args_size *args_size,
2773 unsigned int preferred_unit_stack_boundary)
2774{
2775 /* The number of bytes to pop so that the stack will be
2776 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
2777 HOST_WIDE_INT adjustment;
2778 /* The alignment of the stack after the arguments are pushed, if we
2779 just pushed the arguments without adjust the stack here. */
2780 unsigned HOST_WIDE_INT unadjusted_alignment;
2781
2782 unadjusted_alignment
2783 = ((stack_pointer_delta + unadjusted_args_size)
2784 % preferred_unit_stack_boundary);
2785
2786 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
2787 as possible -- leaving just enough left to cancel out the
2788 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
2789 PENDING_STACK_ADJUST is non-negative, and congruent to
2790 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
2791
2792 /* Begin by trying to pop all the bytes. */
2793 unadjusted_alignment
2794 = (unadjusted_alignment
2795 - (pending_stack_adjust % preferred_unit_stack_boundary));
2796 adjustment = pending_stack_adjust;
2797 /* Push enough additional bytes that the stack will be aligned
2798 after the arguments are pushed. */
2799 if (preferred_unit_stack_boundary > 1 && unadjusted_alignment)
2800 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
2801
2802 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
2803 bytes after the call. The right number is the entire
2804 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
2805 by the arguments in the first place. */
2806 args_size->constant
2807 = pending_stack_adjust - adjustment + unadjusted_args_size;
2808
2809 return adjustment;
2810}
2811
2812/* Scan X expression if it does not dereference any argument slots
2813 we already clobbered by tail call arguments (as noted in stored_args_map
2814 bitmap).
2815 Return nonzero if X expression dereferences such argument slots,
2816 zero otherwise. */
2817
2818static int
2819check_sibcall_argument_overlap_1 (rtx x)
2820{
2821 RTX_CODE code;
2822 int i, j;
2823 const char *fmt;
2824
2825 if (x == NULL_RTX)
2826 return 0;
2827
2828 code = GET_CODE (x);
2829
2830 /* We need not check the operands of the CALL expression itself. */
2831 if (code == CALL)
2832 return 0;
2833
2834 if (code == MEM)
2835 return mem_overlaps_already_clobbered_arg_p (XEXP (x, 0),
2836 GET_MODE_SIZE (GET_MODE (x)));
2837
2838 /* Scan all subexpressions. */
2839 fmt = GET_RTX_FORMAT (code);
2840 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2841 {
2842 if (*fmt == 'e')
2843 {
2844 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2845 return 1;
2846 }
2847 else if (*fmt == 'E')
2848 {
2849 for (j = 0; j < XVECLEN (x, i); j++)
2850 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2851 return 1;
2852 }
2853 }
2854 return 0;
2855}
2856
2857/* Scan sequence after INSN if it does not dereference any argument slots
2858 we already clobbered by tail call arguments (as noted in stored_args_map
2859 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
2860 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
2861 should be 0). Return nonzero if sequence after INSN dereferences such argument
2862 slots, zero otherwise. */
2863
2864static int
2865check_sibcall_argument_overlap (rtx_insn *insn, struct arg_data *arg,
2866 int mark_stored_args_map)
2867{
2868 int low, high;
2869
2870 if (insn == NULL_RTX)
2871 insn = get_insns ();
2872 else
2873 insn = NEXT_INSN (insn);
2874
2875 for (; insn; insn = NEXT_INSN (insn))
2876 if (INSN_P (insn)
2877 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2878 break;
2879
2880 if (mark_stored_args_map)
2881 {
2882 if (ARGS_GROW_DOWNWARD)
2883 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
2884 else
2885 low = arg->locate.slot_offset.constant;
2886
2887 for (high = low + arg->locate.size.constant; low < high; low++)
2888 bitmap_set_bit (stored_args_map, low);
2889 }
2890 return insn != NULL_RTX;
2891}
2892
2893/* Given that a function returns a value of mode MODE at the most
2894 significant end of hard register VALUE, shift VALUE left or right
2895 as specified by LEFT_P. Return true if some action was needed. */
2896
2897bool
2898shift_return_value (machine_mode mode, bool left_p, rtx value)
2899{
2900 HOST_WIDE_INT shift;
2901
2902 gcc_assert (REG_P (value) && HARD_REGISTER_P (value));
2903 shift = GET_MODE_BITSIZE (GET_MODE (value)) - GET_MODE_BITSIZE (mode);
2904 if (shift == 0)
2905 return false;
2906
2907 /* Use ashr rather than lshr for right shifts. This is for the benefit
2908 of the MIPS port, which requires SImode values to be sign-extended
2909 when stored in 64-bit registers. */
2910 if (!force_expand_binop (GET_MODE (value), left_p ? ashl_optab : ashr_optab,
2911 value, GEN_INT (shift), value, 1, OPTAB_WIDEN))
2912 gcc_unreachable ();
2913 return true;
2914}
2915
2916/* If X is a likely-spilled register value, copy it to a pseudo
2917 register and return that register. Return X otherwise. */
2918
2919static rtx
2920avoid_likely_spilled_reg (rtx x)
2921{
2922 rtx new_rtx;
2923
2924 if (REG_P (x)
2925 && HARD_REGISTER_P (x)
2926 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x))))
2927 {
2928 /* Make sure that we generate a REG rather than a CONCAT.
2929 Moves into CONCATs can need nontrivial instructions,
2930 and the whole point of this function is to avoid
2931 using the hard register directly in such a situation. */
2932 generating_concat_p = 0;
2933 new_rtx = gen_reg_rtx (GET_MODE (x));
2934 generating_concat_p = 1;
2935 emit_move_insn (new_rtx, x);
2936 return new_rtx;
2937 }
2938 return x;
2939}
2940
2941/* Helper function for expand_call.
2942 Return false is EXP is not implementable as a sibling call. */
2943
2944static bool
2945can_implement_as_sibling_call_p (tree exp,
2946 rtx structure_value_addr,
2947 tree funtype,
2948 int reg_parm_stack_space ATTRIBUTE_UNUSED,
2949 tree fndecl,
2950 int flags,
2951 tree addr,
2952 const args_size &args_size)
2953{
2954 if (!targetm.have_sibcall_epilogue ())
2955 {
2956 maybe_complain_about_tail_call
2957 (exp,
2958 "machine description does not have"
2959 " a sibcall_epilogue instruction pattern");
2960 return false;
2961 }
2962
2963 /* Doing sibling call optimization needs some work, since
2964 structure_value_addr can be allocated on the stack.
2965 It does not seem worth the effort since few optimizable
2966 sibling calls will return a structure. */
2967 if (structure_value_addr != NULL_RTX)
2968 {
2969 maybe_complain_about_tail_call (exp, "callee returns a structure");
2970 return false;
2971 }
2972
2973#ifdef REG_PARM_STACK_SPACE
2974 /* If outgoing reg parm stack space changes, we can not do sibcall. */
2975 if (OUTGOING_REG_PARM_STACK_SPACE (funtype)
2976 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl))
2977 || (reg_parm_stack_space != REG_PARM_STACK_SPACE (current_function_decl)))
2978 {
2979 maybe_complain_about_tail_call (exp,
2980 "inconsistent size of stack space"
2981 " allocated for arguments which are"
2982 " passed in registers");
2983 return false;
2984 }
2985#endif
2986
2987 /* Check whether the target is able to optimize the call
2988 into a sibcall. */
2989 if (!targetm.function_ok_for_sibcall (fndecl, exp))
2990 {
2991 maybe_complain_about_tail_call (exp,
2992 "target is not able to optimize the"
2993 " call into a sibling call");
2994 return false;
2995 }
2996
2997 /* Functions that do not return exactly once may not be sibcall
2998 optimized. */
2999 if (flags & ECF_RETURNS_TWICE)
3000 {
3001 maybe_complain_about_tail_call (exp, "callee returns twice");
3002 return false;
3003 }
3004 if (flags & ECF_NORETURN)
3005 {
3006 maybe_complain_about_tail_call (exp, "callee does not return");
3007 return false;
3008 }
3009
3010 if (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr))))
3011 {
3012 maybe_complain_about_tail_call (exp, "volatile function type");
3013 return false;
3014 }
3015
3016 /* If the called function is nested in the current one, it might access
3017 some of the caller's arguments, but could clobber them beforehand if
3018 the argument areas are shared. */
3019 if (fndecl && decl_function_context (fndecl) == current_function_decl)
3020 {
3021 maybe_complain_about_tail_call (exp, "nested function");
3022 return false;
3023 }
3024
3025 /* If this function requires more stack slots than the current
3026 function, we cannot change it into a sibling call.
3027 crtl->args.pretend_args_size is not part of the
3028 stack allocated by our caller. */
3029 if (args_size.constant > (crtl->args.size - crtl->args.pretend_args_size))
3030 {
3031 maybe_complain_about_tail_call (exp,
3032 "callee required more stack slots"
3033 " than the caller");
3034 return false;
3035 }
3036
3037 /* If the callee pops its own arguments, then it must pop exactly
3038 the same number of arguments as the current function. */
3039 if (targetm.calls.return_pops_args (fndecl, funtype, args_size.constant)
3040 != targetm.calls.return_pops_args (current_function_decl,
3041 TREE_TYPE (current_function_decl),
3042 crtl->args.size))
3043 {
3044 maybe_complain_about_tail_call (exp,
3045 "inconsistent number of"
3046 " popped arguments");
3047 return false;
3048 }
3049
3050 if (!lang_hooks.decls.ok_for_sibcall (fndecl))
3051 {
3052 maybe_complain_about_tail_call (exp, "frontend does not support"
3053 " sibling call");
3054 return false;
3055 }
3056
3057 /* All checks passed. */
3058 return true;
3059}
3060
3061/* Generate all the code for a CALL_EXPR exp
3062 and return an rtx for its value.
3063 Store the value in TARGET (specified as an rtx) if convenient.
3064 If the value is stored in TARGET then TARGET is returned.
3065 If IGNORE is nonzero, then we ignore the value of the function call. */
3066
3067rtx
3068expand_call (tree exp, rtx target, int ignore)
3069{
3070 /* Nonzero if we are currently expanding a call. */
3071 static int currently_expanding_call = 0;
3072
3073 /* RTX for the function to be called. */
3074 rtx funexp;
3075 /* Sequence of insns to perform a normal "call". */
3076 rtx_insn *normal_call_insns = NULL;
3077 /* Sequence of insns to perform a tail "call". */
3078 rtx_insn *tail_call_insns = NULL;
3079 /* Data type of the function. */
3080 tree funtype;
3081 tree type_arg_types;
3082 tree rettype;
3083 /* Declaration of the function being called,
3084 or 0 if the function is computed (not known by name). */
3085 tree fndecl = 0;
3086 /* The type of the function being called. */
3087 tree fntype;
3088 bool try_tail_call = CALL_EXPR_TAILCALL (exp);
3089 bool must_tail_call = CALL_EXPR_MUST_TAIL_CALL (exp);
3090 int pass;
3091
3092 /* Register in which non-BLKmode value will be returned,
3093 or 0 if no value or if value is BLKmode. */
3094 rtx valreg;
3095 /* Register(s) in which bounds are returned. */
3096 rtx valbnd = NULL;
3097 /* Address where we should return a BLKmode value;
3098 0 if value not BLKmode. */
3099 rtx structure_value_addr = 0;
3100 /* Nonzero if that address is being passed by treating it as
3101 an extra, implicit first parameter. Otherwise,
3102 it is passed by being copied directly into struct_value_rtx. */
3103 int structure_value_addr_parm = 0;
3104 /* Holds the value of implicit argument for the struct value. */
3105 tree structure_value_addr_value = NULL_TREE;
3106 /* Size of aggregate value wanted, or zero if none wanted
3107 or if we are using the non-reentrant PCC calling convention
3108 or expecting the value in registers. */
3109 HOST_WIDE_INT struct_value_size = 0;
3110 /* Nonzero if called function returns an aggregate in memory PCC style,
3111 by returning the address of where to find it. */
3112 int pcc_struct_value = 0;
3113 rtx struct_value = 0;
3114
3115 /* Number of actual parameters in this call, including struct value addr. */
3116 int num_actuals;
3117 /* Number of named args. Args after this are anonymous ones
3118 and they must all go on the stack. */
3119 int n_named_args;
3120 /* Number of complex actual arguments that need to be split. */
3121 int num_complex_actuals = 0;
3122
3123 /* Vector of information about each argument.
3124 Arguments are numbered in the order they will be pushed,
3125 not the order they are written. */
3126 struct arg_data *args;
3127
3128 /* Total size in bytes of all the stack-parms scanned so far. */
3129 struct args_size args_size;
3130 struct args_size adjusted_args_size;
3131 /* Size of arguments before any adjustments (such as rounding). */
3132 int unadjusted_args_size;
3133 /* Data on reg parms scanned so far. */
3134 CUMULATIVE_ARGS args_so_far_v;
3135 cumulative_args_t args_so_far;
3136 /* Nonzero if a reg parm has been scanned. */
3137 int reg_parm_seen;
3138 /* Nonzero if this is an indirect function call. */
3139
3140 /* Nonzero if we must avoid push-insns in the args for this call.
3141 If stack space is allocated for register parameters, but not by the
3142 caller, then it is preallocated in the fixed part of the stack frame.
3143 So the entire argument block must then be preallocated (i.e., we
3144 ignore PUSH_ROUNDING in that case). */
3145
3146 int must_preallocate = !PUSH_ARGS;
3147
3148 /* Size of the stack reserved for parameter registers. */
3149 int reg_parm_stack_space = 0;
3150
3151 /* Address of space preallocated for stack parms
3152 (on machines that lack push insns), or 0 if space not preallocated. */
3153 rtx argblock = 0;
3154
3155 /* Mask of ECF_ and ERF_ flags. */
3156 int flags = 0;
3157 int return_flags = 0;
3158#ifdef REG_PARM_STACK_SPACE
3159 /* Define the boundary of the register parm stack space that needs to be
3160 saved, if any. */
3161 int low_to_save, high_to_save;
3162 rtx save_area = 0; /* Place that it is saved */
3163#endif
3164
3165 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3166 char *initial_stack_usage_map = stack_usage_map;
3167 char *stack_usage_map_buf = NULL;
3168
3169 int old_stack_allocated;
3170
3171 /* State variables to track stack modifications. */
3172 rtx old_stack_level = 0;
3173 int old_stack_arg_under_construction = 0;
3174 int old_pending_adj = 0;
3175 int old_inhibit_defer_pop = inhibit_defer_pop;
3176
3177 /* Some stack pointer alterations we make are performed via
3178 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
3179 which we then also need to save/restore along the way. */
3180 int old_stack_pointer_delta = 0;
3181
3182 rtx call_fusage;
3183 tree addr = CALL_EXPR_FN (exp);
3184 int i;
3185 /* The alignment of the stack, in bits. */
3186 unsigned HOST_WIDE_INT preferred_stack_boundary;
3187 /* The alignment of the stack, in bytes. */
3188 unsigned HOST_WIDE_INT preferred_unit_stack_boundary;
3189 /* The static chain value to use for this call. */
3190 rtx static_chain_value;
3191 /* See if this is "nothrow" function call. */
3192 if (TREE_NOTHROW (exp))
3193 flags |= ECF_NOTHROW;
3194
3195 /* See if we can find a DECL-node for the actual function, and get the
3196 function attributes (flags) from the function decl or type node. */
3197 fndecl = get_callee_fndecl (exp);
3198 if (fndecl)
3199 {
3200 fntype = TREE_TYPE (fndecl);
3201 flags |= flags_from_decl_or_type (fndecl);
3202 return_flags |= decl_return_flags (fndecl);
3203 }
3204 else
3205 {
3206 fntype = TREE_TYPE (TREE_TYPE (addr));
3207 flags |= flags_from_decl_or_type (fntype);
3208 if (CALL_EXPR_BY_DESCRIPTOR (exp))
3209 flags |= ECF_BY_DESCRIPTOR;
3210 }
3211 rettype = TREE_TYPE (exp);
3212
3213 struct_value = targetm.calls.struct_value_rtx (fntype, 0);
3214
3215 /* Warn if this value is an aggregate type,
3216 regardless of which calling convention we are using for it. */
3217 if (AGGREGATE_TYPE_P (rettype))
3218 warning (OPT_Waggregate_return, "function call has aggregate value");
3219
3220 /* If the result of a non looping pure or const function call is
3221 ignored (or void), and none of its arguments are volatile, we can
3222 avoid expanding the call and just evaluate the arguments for
3223 side-effects. */
3224 if ((flags & (ECF_CONST | ECF_PURE))
3225 && (!(flags & ECF_LOOPING_CONST_OR_PURE))
3226 && (ignore || target == const0_rtx
3227 || TYPE_MODE (rettype) == VOIDmode))
3228 {
3229 bool volatilep = false;
3230 tree arg;
3231 call_expr_arg_iterator iter;
3232
3233 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
3234 if (TREE_THIS_VOLATILE (arg))
3235 {
3236 volatilep = true;
3237 break;
3238 }
3239
3240 if (! volatilep)
3241 {
3242 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
3243 expand_expr (arg, const0_rtx, VOIDmode, EXPAND_NORMAL);
3244 return const0_rtx;
3245 }
3246 }
3247
3248#ifdef REG_PARM_STACK_SPACE
3249 reg_parm_stack_space = REG_PARM_STACK_SPACE (!fndecl ? fntype : fndecl);
3250#endif
3251
3252 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
3253 && reg_parm_stack_space > 0 && PUSH_ARGS)
3254 must_preallocate = 1;
3255
3256 /* Set up a place to return a structure. */
3257
3258 /* Cater to broken compilers. */
3259 if (aggregate_value_p (exp, fntype))
3260 {
3261 /* This call returns a big structure. */
3262 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
3263
3264#ifdef PCC_STATIC_STRUCT_RETURN
3265 {
3266 pcc_struct_value = 1;
3267 }
3268#else /* not PCC_STATIC_STRUCT_RETURN */
3269 {
3270 struct_value_size = int_size_in_bytes (rettype);
3271
3272 /* Even if it is semantically safe to use the target as the return
3273 slot, it may be not sufficiently aligned for the return type. */
3274 if (CALL_EXPR_RETURN_SLOT_OPT (exp)
3275 && target
3276 && MEM_P (target)
3277 && !(MEM_ALIGN (target) < TYPE_ALIGN (rettype)
3278 && targetm.slow_unaligned_access (TYPE_MODE (rettype),
3279 MEM_ALIGN (target))))
3280 structure_value_addr = XEXP (target, 0);
3281 else
3282 {
3283 /* For variable-sized objects, we must be called with a target
3284 specified. If we were to allocate space on the stack here,
3285 we would have no way of knowing when to free it. */
3286 rtx d = assign_temp (rettype, 1, 1);
3287 structure_value_addr = XEXP (d, 0);
3288 target = 0;
3289 }
3290 }
3291#endif /* not PCC_STATIC_STRUCT_RETURN */
3292 }
3293
3294 /* Figure out the amount to which the stack should be aligned. */
3295 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3296 if (fndecl)
3297 {
3298 struct cgraph_rtl_info *i = cgraph_node::rtl_info (fndecl);
3299 /* Without automatic stack alignment, we can't increase preferred
3300 stack boundary. With automatic stack alignment, it is
3301 unnecessary since unless we can guarantee that all callers will
3302 align the outgoing stack properly, callee has to align its
3303 stack anyway. */
3304 if (i
3305 && i->preferred_incoming_stack_boundary
3306 && i->preferred_incoming_stack_boundary < preferred_stack_boundary)
3307 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
3308 }
3309
3310 /* Operand 0 is a pointer-to-function; get the type of the function. */
3311 funtype = TREE_TYPE (addr);
3312 gcc_assert (POINTER_TYPE_P (funtype));
3313 funtype = TREE_TYPE (funtype);
3314
3315 /* Count whether there are actual complex arguments that need to be split
3316 into their real and imaginary parts. Munge the type_arg_types
3317 appropriately here as well. */
3318 if (targetm.calls.split_complex_arg)
3319 {
3320 call_expr_arg_iterator iter;
3321 tree arg;
3322 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
3323 {
3324 tree type = TREE_TYPE (arg);
3325 if (type && TREE_CODE (type) == COMPLEX_TYPE
3326 && targetm.calls.split_complex_arg (type))
3327 num_complex_actuals++;
3328 }
3329 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
3330 }
3331 else
3332 type_arg_types = TYPE_ARG_TYPES (funtype);
3333
3334 if (flags & ECF_MAY_BE_ALLOCA)
3335 cfun->calls_alloca = 1;
3336
3337 /* If struct_value_rtx is 0, it means pass the address
3338 as if it were an extra parameter. Put the argument expression
3339 in structure_value_addr_value. */
3340 if (structure_value_addr && struct_value == 0)
3341 {
3342 /* If structure_value_addr is a REG other than
3343 virtual_outgoing_args_rtx, we can use always use it. If it
3344 is not a REG, we must always copy it into a register.
3345 If it is virtual_outgoing_args_rtx, we must copy it to another
3346 register in some cases. */
3347 rtx temp = (!REG_P (structure_value_addr)
3348 || (ACCUMULATE_OUTGOING_ARGS
3349 && stack_arg_under_construction
3350 && structure_value_addr == virtual_outgoing_args_rtx)
3351 ? copy_addr_to_reg (convert_memory_address
3352 (Pmode, structure_value_addr))
3353 : structure_value_addr);
3354
3355 structure_value_addr_value =
3356 make_tree (build_pointer_type (TREE_TYPE (funtype)), temp);
3357 structure_value_addr_parm = CALL_WITH_BOUNDS_P (exp) ? 2 : 1;
3358 }
3359
3360 /* Count the arguments and set NUM_ACTUALS. */
3361 num_actuals =
3362 call_expr_nargs (exp) + num_complex_actuals + structure_value_addr_parm;
3363
3364 /* Compute number of named args.
3365 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
3366
3367 if (type_arg_types != 0)
3368 n_named_args
3369 = (list_length (type_arg_types)
3370 /* Count the struct value address, if it is passed as a parm. */
3371 + structure_value_addr_parm);
3372 else
3373 /* If we know nothing, treat all args as named. */
3374 n_named_args = num_actuals;
3375
3376 /* Start updating where the next arg would go.
3377
3378 On some machines (such as the PA) indirect calls have a different
3379 calling convention than normal calls. The fourth argument in
3380 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
3381 or not. */
3382 INIT_CUMULATIVE_ARGS (args_so_far_v, funtype, NULL_RTX, fndecl, n_named_args);
3383 args_so_far = pack_cumulative_args (&args_so_far_v);
3384
3385 /* Now possibly adjust the number of named args.
3386 Normally, don't include the last named arg if anonymous args follow.
3387 We do include the last named arg if
3388 targetm.calls.strict_argument_naming() returns nonzero.
3389 (If no anonymous args follow, the result of list_length is actually
3390 one too large. This is harmless.)
3391
3392 If targetm.calls.pretend_outgoing_varargs_named() returns
3393 nonzero, and targetm.calls.strict_argument_naming() returns zero,
3394 this machine will be able to place unnamed args that were passed
3395 in registers into the stack. So treat all args as named. This
3396 allows the insns emitting for a specific argument list to be
3397 independent of the function declaration.
3398
3399 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
3400 we do not have any reliable way to pass unnamed args in
3401 registers, so we must force them into memory. */
3402
3403 if (type_arg_types != 0
3404 && targetm.calls.strict_argument_naming (args_so_far))
3405 ;
3406 else if (type_arg_types != 0
3407 && ! targetm.calls.pretend_outgoing_varargs_named (args_so_far))
3408 /* Don't include the last named arg. */
3409 --n_named_args;
3410 else
3411 /* Treat all args as named. */
3412 n_named_args = num_actuals;
3413
3414 /* Make a vector to hold all the information about each arg. */
3415 args = XCNEWVEC (struct arg_data, num_actuals);
3416
3417 /* Build up entries in the ARGS array, compute the size of the
3418 arguments into ARGS_SIZE, etc. */
3419 initialize_argument_information (num_actuals, args, &args_size,
3420 n_named_args, exp,
3421 structure_value_addr_value, fndecl, fntype,
3422 args_so_far, reg_parm_stack_space,
3423 &old_stack_level, &old_pending_adj,
3424 &must_preallocate, &flags,
3425 &try_tail_call, CALL_FROM_THUNK_P (exp));
3426
3427 if (args_size.var)
3428 must_preallocate = 1;
3429
3430 /* Now make final decision about preallocating stack space. */
3431 must_preallocate = finalize_must_preallocate (must_preallocate,
3432 num_actuals, args,
3433 &args_size);
3434
3435 /* If the structure value address will reference the stack pointer, we
3436 must stabilize it. We don't need to do this if we know that we are
3437 not going to adjust the stack pointer in processing this call. */
3438
3439 if (structure_value_addr
3440 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
3441 || reg_mentioned_p (virtual_outgoing_args_rtx,
3442 structure_value_addr))
3443 && (args_size.var
3444 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
3445 structure_value_addr = copy_to_reg (structure_value_addr);
3446
3447 /* Tail calls can make things harder to debug, and we've traditionally
3448 pushed these optimizations into -O2. Don't try if we're already
3449 expanding a call, as that means we're an argument. Don't try if
3450 there's cleanups, as we know there's code to follow the call. */
3451
3452 if (currently_expanding_call++ != 0
3453 || !flag_optimize_sibling_calls
3454 || args_size.var
3455 || dbg_cnt (tail_call) == false)
3456 try_tail_call = 0;
3457
3458 /* If the user has marked the function as requiring tail-call
3459 optimization, attempt it. */
3460 if (must_tail_call)
3461 try_tail_call = 1;
3462
3463 /* Rest of purposes for tail call optimizations to fail. */
3464 if (try_tail_call)
3465 try_tail_call = can_implement_as_sibling_call_p (exp,
3466 structure_value_addr,
3467 funtype,
3468 reg_parm_stack_space,
3469 fndecl,
3470 flags, addr, args_size);
3471
3472 /* Check if caller and callee disagree in promotion of function
3473 return value. */
3474 if (try_tail_call)
3475 {
3476 machine_mode caller_mode, caller_promoted_mode;
3477 machine_mode callee_mode, callee_promoted_mode;
3478 int caller_unsignedp, callee_unsignedp;
3479 tree caller_res = DECL_RESULT (current_function_decl);
3480
3481 caller_unsignedp = TYPE_UNSIGNED (TREE_TYPE (caller_res));
3482 caller_mode = DECL_MODE (caller_res);
3483 callee_unsignedp = TYPE_UNSIGNED (TREE_TYPE (funtype));
3484 callee_mode = TYPE_MODE (TREE_TYPE (funtype));
3485 caller_promoted_mode
3486 = promote_function_mode (TREE_TYPE (caller_res), caller_mode,
3487 &caller_unsignedp,
3488 TREE_TYPE (current_function_decl), 1);
3489 callee_promoted_mode
3490 = promote_function_mode (TREE_TYPE (funtype), callee_mode,
3491 &callee_unsignedp,
3492 funtype, 1);
3493 if (caller_mode != VOIDmode
3494 && (caller_promoted_mode != callee_promoted_mode
3495 || ((caller_mode != caller_promoted_mode
3496 || callee_mode != callee_promoted_mode)
3497 && (caller_unsignedp != callee_unsignedp
3498 || partial_subreg_p (caller_mode, callee_mode)))))
3499 {
3500 try_tail_call = 0;
3501 maybe_complain_about_tail_call (exp,
3502 "caller and callee disagree in"
3503 " promotion of function"
3504 " return value");
3505 }
3506 }
3507
3508 /* Ensure current function's preferred stack boundary is at least
3509 what we need. Stack alignment may also increase preferred stack
3510 boundary. */
3511 if (crtl->preferred_stack_boundary < preferred_stack_boundary)
3512 crtl->preferred_stack_boundary = preferred_stack_boundary;
3513 else
3514 preferred_stack_boundary = crtl->preferred_stack_boundary;
3515
3516 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
3517
3518 /* We want to make two insn chains; one for a sibling call, the other
3519 for a normal call. We will select one of the two chains after
3520 initial RTL generation is complete. */
3521 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
3522 {
3523 int sibcall_failure = 0;
3524 /* We want to emit any pending stack adjustments before the tail
3525 recursion "call". That way we know any adjustment after the tail
3526 recursion call can be ignored if we indeed use the tail
3527 call expansion. */
3528 saved_pending_stack_adjust save;
3529 rtx_insn *insns, *before_call, *after_args;
3530 rtx next_arg_reg;
3531
3532 if (pass == 0)
3533 {
3534 /* State variables we need to save and restore between
3535 iterations. */
3536 save_pending_stack_adjust (&save);
3537 }
3538 if (pass)
3539 flags &= ~ECF_SIBCALL;
3540 else
3541 flags |= ECF_SIBCALL;
3542
3543 /* Other state variables that we must reinitialize each time
3544 through the loop (that are not initialized by the loop itself). */
3545 argblock = 0;
3546 call_fusage = 0;
3547
3548 /* Start a new sequence for the normal call case.
3549
3550 From this point on, if the sibling call fails, we want to set
3551 sibcall_failure instead of continuing the loop. */
3552 start_sequence ();
3553
3554 /* Don't let pending stack adjusts add up to too much.
3555 Also, do all pending adjustments now if there is any chance
3556 this might be a call to alloca or if we are expanding a sibling
3557 call sequence.
3558 Also do the adjustments before a throwing call, otherwise
3559 exception handling can fail; PR 19225. */
3560 if (pending_stack_adjust >= 32
3561 || (pending_stack_adjust > 0
3562 && (flags & ECF_MAY_BE_ALLOCA))
3563 || (pending_stack_adjust > 0
3564 && flag_exceptions && !(flags & ECF_NOTHROW))
3565 || pass == 0)
3566 do_pending_stack_adjust ();
3567
3568 /* Precompute any arguments as needed. */
3569 if (pass)
3570 precompute_arguments (num_actuals, args);
3571
3572 /* Now we are about to start emitting insns that can be deleted
3573 if a libcall is deleted. */
3574 if (pass && (flags & ECF_MALLOC))
3575 start_sequence ();
3576
3577 if (pass == 0
3578 && crtl->stack_protect_guard
3579 && targetm.stack_protect_runtime_enabled_p ())
3580 stack_protect_epilogue ();
3581
3582 adjusted_args_size = args_size;
3583 /* Compute the actual size of the argument block required. The variable
3584 and constant sizes must be combined, the size may have to be rounded,
3585 and there may be a minimum required size. When generating a sibcall
3586 pattern, do not round up, since we'll be re-using whatever space our
3587 caller provided. */
3588 unadjusted_args_size
3589 = compute_argument_block_size (reg_parm_stack_space,
3590 &adjusted_args_size,
3591 fndecl, fntype,
3592 (pass == 0 ? 0
3593 : preferred_stack_boundary));
3594
3595 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
3596
3597 /* The argument block when performing a sibling call is the
3598 incoming argument block. */
3599 if (pass == 0)
3600 {
3601 argblock = crtl->args.internal_arg_pointer;
3602 if (STACK_GROWS_DOWNWARD)
3603 argblock
3604 = plus_constant (Pmode, argblock, crtl->args.pretend_args_size);
3605 else
3606 argblock
3607 = plus_constant (Pmode, argblock, -crtl->args.pretend_args_size);
3608
3609 stored_args_map = sbitmap_alloc (args_size.constant);
3610 bitmap_clear (stored_args_map);
3611 }
3612
3613 /* If we have no actual push instructions, or shouldn't use them,
3614 make space for all args right now. */
3615 else if (adjusted_args_size.var != 0)
3616 {
3617 if (old_stack_level == 0)
3618 {
3619 emit_stack_save (SAVE_BLOCK, &old_stack_level);
3620 old_stack_pointer_delta = stack_pointer_delta;
3621 old_pending_adj = pending_stack_adjust;
3622 pending_stack_adjust = 0;
3623 /* stack_arg_under_construction says whether a stack arg is
3624 being constructed at the old stack level. Pushing the stack
3625 gets a clean outgoing argument block. */
3626 old_stack_arg_under_construction = stack_arg_under_construction;
3627 stack_arg_under_construction = 0;
3628 }
3629 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
3630 if (flag_stack_usage_info)
3631 current_function_has_unbounded_dynamic_stack_size = 1;
3632 }
3633 else
3634 {
3635 /* Note that we must go through the motions of allocating an argument
3636 block even if the size is zero because we may be storing args
3637 in the area reserved for register arguments, which may be part of
3638 the stack frame. */
3639
3640 int needed = adjusted_args_size.constant;
3641
3642 /* Store the maximum argument space used. It will be pushed by
3643 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
3644 checking). */
3645
3646 if (needed > crtl->outgoing_args_size)
3647 crtl->outgoing_args_size = needed;
3648
3649 if (must_preallocate)
3650 {
3651 if (ACCUMULATE_OUTGOING_ARGS)
3652 {
3653 /* Since the stack pointer will never be pushed, it is
3654 possible for the evaluation of a parm to clobber
3655 something we have already written to the stack.
3656 Since most function calls on RISC machines do not use
3657 the stack, this is uncommon, but must work correctly.
3658
3659 Therefore, we save any area of the stack that was already
3660 written and that we are using. Here we set up to do this
3661 by making a new stack usage map from the old one. The
3662 actual save will be done by store_one_arg.
3663
3664 Another approach might be to try to reorder the argument
3665 evaluations to avoid this conflicting stack usage. */
3666
3667 /* Since we will be writing into the entire argument area,
3668 the map must be allocated for its entire size, not just
3669 the part that is the responsibility of the caller. */
3670 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
3671 needed += reg_parm_stack_space;
3672
3673 if (ARGS_GROW_DOWNWARD)
3674 highest_outgoing_arg_in_use
3675 = MAX (initial_highest_arg_in_use, needed + 1);
3676 else
3677 highest_outgoing_arg_in_use
3678 = MAX (initial_highest_arg_in_use, needed);
3679
3680 free (stack_usage_map_buf);
3681 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
3682 stack_usage_map = stack_usage_map_buf;
3683
3684 if (initial_highest_arg_in_use)
3685 memcpy (stack_usage_map, initial_stack_usage_map,
3686 initial_highest_arg_in_use);
3687
3688 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3689 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3690 (highest_outgoing_arg_in_use
3691 - initial_highest_arg_in_use));
3692 needed = 0;
3693
3694 /* The address of the outgoing argument list must not be
3695 copied to a register here, because argblock would be left
3696 pointing to the wrong place after the call to
3697 allocate_dynamic_stack_space below. */
3698
3699 argblock = virtual_outgoing_args_rtx;
3700 }
3701 else
3702 {
3703 if (inhibit_defer_pop == 0)
3704 {
3705 /* Try to reuse some or all of the pending_stack_adjust
3706 to get this space. */
3707 needed
3708 = (combine_pending_stack_adjustment_and_call
3709 (unadjusted_args_size,
3710 &adjusted_args_size,
3711 preferred_unit_stack_boundary));
3712
3713 /* combine_pending_stack_adjustment_and_call computes
3714 an adjustment before the arguments are allocated.
3715 Account for them and see whether or not the stack
3716 needs to go up or down. */
3717 needed = unadjusted_args_size - needed;
3718
3719 if (needed < 0)
3720 {
3721 /* We're releasing stack space. */
3722 /* ??? We can avoid any adjustment at all if we're
3723 already aligned. FIXME. */
3724 pending_stack_adjust = -needed;
3725 do_pending_stack_adjust ();
3726 needed = 0;
3727 }
3728 else
3729 /* We need to allocate space. We'll do that in
3730 push_block below. */
3731 pending_stack_adjust = 0;
3732 }
3733
3734 /* Special case this because overhead of `push_block' in
3735 this case is non-trivial. */
3736 if (needed == 0)
3737 argblock = virtual_outgoing_args_rtx;
3738 else
3739 {
3740 argblock = push_block (GEN_INT (needed), 0, 0);
3741 if (ARGS_GROW_DOWNWARD)
3742 argblock = plus_constant (Pmode, argblock, needed);
3743 }
3744
3745 /* We only really need to call `copy_to_reg' in the case
3746 where push insns are going to be used to pass ARGBLOCK
3747 to a function call in ARGS. In that case, the stack
3748 pointer changes value from the allocation point to the
3749 call point, and hence the value of
3750 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
3751 as well always do it. */
3752 argblock = copy_to_reg (argblock);
3753 }
3754 }
3755 }
3756
3757 if (ACCUMULATE_OUTGOING_ARGS)
3758 {
3759 /* The save/restore code in store_one_arg handles all
3760 cases except one: a constructor call (including a C
3761 function returning a BLKmode struct) to initialize
3762 an argument. */
3763 if (stack_arg_under_construction)
3764 {
3765 rtx push_size
3766 = GEN_INT (adjusted_args_size.constant
3767 + (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype
3768 : TREE_TYPE (fndecl))) ? 0
3769 : reg_parm_stack_space));
3770 if (old_stack_level == 0)
3771 {
3772 emit_stack_save (SAVE_BLOCK, &old_stack_level);
3773 old_stack_pointer_delta = stack_pointer_delta;
3774 old_pending_adj = pending_stack_adjust;
3775 pending_stack_adjust = 0;
3776 /* stack_arg_under_construction says whether a stack
3777 arg is being constructed at the old stack level.
3778 Pushing the stack gets a clean outgoing argument
3779 block. */
3780 old_stack_arg_under_construction
3781 = stack_arg_under_construction;
3782 stack_arg_under_construction = 0;
3783 /* Make a new map for the new argument list. */
3784 free (stack_usage_map_buf);
3785 stack_usage_map_buf = XCNEWVEC (char, highest_outgoing_arg_in_use);
3786 stack_usage_map = stack_usage_map_buf;
3787 highest_outgoing_arg_in_use = 0;
3788 }
3789 /* We can pass TRUE as the 4th argument because we just
3790 saved the stack pointer and will restore it right after
3791 the call. */
3792 allocate_dynamic_stack_space (push_size, 0, BIGGEST_ALIGNMENT,
3793 -1, true);
3794 }
3795
3796 /* If argument evaluation might modify the stack pointer,
3797 copy the address of the argument list to a register. */
3798 for (i = 0; i < num_actuals; i++)
3799 if (args[i].pass_on_stack)
3800 {
3801 argblock = copy_addr_to_reg (argblock);
3802 break;
3803 }
3804 }
3805
3806 compute_argument_addresses (args, argblock, num_actuals);
3807
3808 /* Stack is properly aligned, pops can't safely be deferred during
3809 the evaluation of the arguments. */
3810 NO_DEFER_POP;
3811
3812 /* Precompute all register parameters. It isn't safe to compute
3813 anything once we have started filling any specific hard regs.
3814 TLS symbols sometimes need a call to resolve. Precompute
3815 register parameters before any stack pointer manipulation
3816 to avoid unaligned stack in the called function. */
3817 precompute_register_parameters (num_actuals, args, &reg_parm_seen);
3818
3819 OK_DEFER_POP;
3820
3821 /* Perform stack alignment before the first push (the last arg). */
3822 if (argblock == 0
3823 && adjusted_args_size.constant > reg_parm_stack_space
3824 && adjusted_args_size.constant != unadjusted_args_size)
3825 {
3826 /* When the stack adjustment is pending, we get better code
3827 by combining the adjustments. */
3828 if (pending_stack_adjust
3829 && ! inhibit_defer_pop)
3830 {
3831 pending_stack_adjust
3832 = (combine_pending_stack_adjustment_and_call
3833 (unadjusted_args_size,
3834 &adjusted_args_size,
3835 preferred_unit_stack_boundary));
3836 do_pending_stack_adjust ();
3837 }
3838 else if (argblock == 0)
3839 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3840 - unadjusted_args_size));
3841 }
3842 /* Now that the stack is properly aligned, pops can't safely
3843 be deferred during the evaluation of the arguments. */
3844 NO_DEFER_POP;
3845
3846 /* Record the maximum pushed stack space size. We need to delay
3847 doing it this far to take into account the optimization done
3848 by combine_pending_stack_adjustment_and_call. */
3849 if (flag_stack_usage_info
3850 && !ACCUMULATE_OUTGOING_ARGS
3851 && pass
3852 && adjusted_args_size.var == 0)
3853 {
3854 int pushed = adjusted_args_size.constant + pending_stack_adjust;
3855 if (pushed > current_function_pushed_stack_size)
3856 current_function_pushed_stack_size = pushed;
3857 }
3858
3859 funexp = rtx_for_function_call (fndecl, addr);
3860
3861 if (CALL_EXPR_STATIC_CHAIN (exp))
3862 static_chain_value = expand_normal (CALL_EXPR_STATIC_CHAIN (exp));
3863 else
3864 static_chain_value = 0;
3865
3866#ifdef REG_PARM_STACK_SPACE
3867 /* Save the fixed argument area if it's part of the caller's frame and
3868 is clobbered by argument setup for this call. */
3869 if (ACCUMULATE_OUTGOING_ARGS && pass)
3870 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3871 &low_to_save, &high_to_save);
3872#endif
3873
3874 /* Now store (and compute if necessary) all non-register parms.
3875 These come before register parms, since they can require block-moves,
3876 which could clobber the registers used for register parms.
3877 Parms which have partial registers are not stored here,
3878 but we do preallocate space here if they want that. */
3879
3880 for (i = 0; i < num_actuals; i++)
3881 {
3882 /* Delay bounds until all other args are stored. */
3883 if (POINTER_BOUNDS_P (args[i].tree_value))
3884 continue;
3885 else if (args[i].reg == 0 || args[i].pass_on_stack)
3886 {
3887 rtx_insn *before_arg = get_last_insn ();
3888
3889 /* We don't allow passing huge (> 2^30 B) arguments
3890 by value. It would cause an overflow later on. */
3891 if (adjusted_args_size.constant
3892 >= (1 << (HOST_BITS_PER_INT - 2)))
3893 {
3894 sorry ("passing too large argument on stack");
3895 continue;
3896 }
3897
3898 if (store_one_arg (&args[i], argblock, flags,
3899 adjusted_args_size.var != 0,
3900 reg_parm_stack_space)
3901 || (pass == 0
3902 && check_sibcall_argument_overlap (before_arg,
3903 &args[i], 1)))
3904 sibcall_failure = 1;
3905 }
3906
3907 if (args[i].stack)
3908 call_fusage
3909 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
3910 gen_rtx_USE (VOIDmode, args[i].stack),
3911 call_fusage);
3912 }
3913
3914 /* If we have a parm that is passed in registers but not in memory
3915 and whose alignment does not permit a direct copy into registers,
3916 make a group of pseudos that correspond to each register that we
3917 will later fill. */
3918 if (STRICT_ALIGNMENT)
3919 store_unaligned_arguments_into_pseudos (args, num_actuals);
3920
3921 /* Now store any partially-in-registers parm.
3922 This is the last place a block-move can happen. */
3923 if (reg_parm_seen)
3924 for (i = 0; i < num_actuals; i++)
3925 if (args[i].partial != 0 && ! args[i].pass_on_stack)
3926 {
3927 rtx_insn *before_arg = get_last_insn ();
3928
3929 /* On targets with weird calling conventions (e.g. PA) it's
3930 hard to ensure that all cases of argument overlap between
3931 stack and registers work. Play it safe and bail out. */
3932 if (ARGS_GROW_DOWNWARD && !STACK_GROWS_DOWNWARD)
3933 {
3934 sibcall_failure = 1;
3935 break;
3936 }
3937
3938 if (store_one_arg (&args[i], argblock, flags,
3939 adjusted_args_size.var != 0,
3940 reg_parm_stack_space)
3941 || (pass == 0
3942 && check_sibcall_argument_overlap (before_arg,
3943 &args[i], 1)))
3944 sibcall_failure = 1;
3945 }
3946
3947 bool any_regs = false;
3948 for (i = 0; i < num_actuals; i++)
3949 if (args[i].reg != NULL_RTX)
3950 {
3951 any_regs = true;
3952 targetm.calls.call_args (args[i].reg, funtype);
3953 }
3954 if (!any_regs)
3955 targetm.calls.call_args (pc_rtx, funtype);
3956
3957 /* Figure out the register where the value, if any, will come back. */
3958 valreg = 0;
3959 valbnd = 0;
3960 if (TYPE_MODE (rettype) != VOIDmode
3961 && ! structure_value_addr)
3962 {
3963 if (pcc_struct_value)
3964 {
3965 valreg = hard_function_value (build_pointer_type (rettype),
3966 fndecl, NULL, (pass == 0));
3967 if (CALL_WITH_BOUNDS_P (exp))
3968 valbnd = targetm.calls.
3969 chkp_function_value_bounds (build_pointer_type (rettype),
3970 fndecl, (pass == 0));
3971 }
3972 else
3973 {
3974 valreg = hard_function_value (rettype, fndecl, fntype,
3975 (pass == 0));
3976 if (CALL_WITH_BOUNDS_P (exp))
3977 valbnd = targetm.calls.chkp_function_value_bounds (rettype,
3978 fndecl,
3979 (pass == 0));
3980 }
3981
3982 /* If VALREG is a PARALLEL whose first member has a zero
3983 offset, use that. This is for targets such as m68k that
3984 return the same value in multiple places. */
3985 if (GET_CODE (valreg) == PARALLEL)
3986 {
3987 rtx elem = XVECEXP (valreg, 0, 0);
3988 rtx where = XEXP (elem, 0);
3989 rtx offset = XEXP (elem, 1);
3990 if (offset == const0_rtx
3991 && GET_MODE (where) == GET_MODE (valreg))
3992 valreg = where;
3993 }
3994 }
3995
3996 /* Store all bounds not passed in registers. */
3997 for (i = 0; i < num_actuals; i++)
3998 {
3999 if (POINTER_BOUNDS_P (args[i].tree_value)
4000 && !args[i].reg)
4001 store_bounds (&args[i],
4002 args[i].pointer_arg == -1
4003 ? NULL
4004 : &args[args[i].pointer_arg]);
4005 }
4006
4007 /* If register arguments require space on the stack and stack space
4008 was not preallocated, allocate stack space here for arguments
4009 passed in registers. */
4010 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
4011 && !ACCUMULATE_OUTGOING_ARGS
4012 && must_preallocate == 0 && reg_parm_stack_space > 0)
4013 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
4014
4015 /* Pass the function the address in which to return a
4016 structure value. */
4017 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
4018 {
4019 structure_value_addr
4020 = convert_memory_address (Pmode, structure_value_addr);
4021 emit_move_insn (struct_value,
4022 force_reg (Pmode,
4023 force_operand (structure_value_addr,
4024 NULL_RTX)));
4025
4026 if (REG_P (struct_value))
4027 use_reg (&call_fusage, struct_value);
4028 }
4029
4030 after_args = get_last_insn ();
4031 funexp = prepare_call_address (fndecl ? fndecl : fntype, funexp,
4032 static_chain_value, &call_fusage,
4033 reg_parm_seen, flags);
4034
4035 load_register_parameters (args, num_actuals, &call_fusage, flags,
4036 pass == 0, &sibcall_failure);
4037
4038 /* Save a pointer to the last insn before the call, so that we can
4039 later safely search backwards to find the CALL_INSN. */
4040 before_call = get_last_insn ();
4041
4042 /* Set up next argument register. For sibling calls on machines
4043 with register windows this should be the incoming register. */
4044 if (pass == 0)
4045 next_arg_reg = targetm.calls.function_incoming_arg (args_so_far,
4046 VOIDmode,
4047 void_type_node,
4048 true);
4049 else
4050 next_arg_reg = targetm.calls.function_arg (args_so_far,
4051 VOIDmode, void_type_node,
4052 true);
4053
4054 if (pass == 1 && (return_flags & ERF_RETURNS_ARG))
4055 {
4056 int arg_nr = return_flags & ERF_RETURN_ARG_MASK;
4057 arg_nr = num_actuals - arg_nr - 1;
4058 if (arg_nr >= 0
4059 && arg_nr < num_actuals
4060 && args[arg_nr].reg
4061 && valreg
4062 && REG_P (valreg)
4063 && GET_MODE (args[arg_nr].reg) == GET_MODE (valreg))
4064 call_fusage
4065 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[arg_nr].tree_value)),
4066 gen_rtx_SET (valreg, args[arg_nr].reg),
4067 call_fusage);
4068 }
4069 /* All arguments and registers used for the call must be set up by
4070 now! */
4071
4072 /* Stack must be properly aligned now. */
4073 gcc_assert (!pass
4074 || !(stack_pointer_delta % preferred_unit_stack_boundary));
4075
4076 /* Generate the actual call instruction. */
4077 emit_call_1 (funexp, exp, fndecl, funtype, unadjusted_args_size,
4078 adjusted_args_size.constant, struct_value_size,
4079 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
4080 flags, args_so_far);
4081
4082 if (flag_ipa_ra)
4083 {
4084 rtx_call_insn *last;
4085 rtx datum = NULL_RTX;
4086 if (fndecl != NULL_TREE)
4087 {
4088 datum = XEXP (DECL_RTL (fndecl), 0);
4089 gcc_assert (datum != NULL_RTX
4090 && GET_CODE (datum) == SYMBOL_REF);
4091 }
4092 last = last_call_insn ();
4093 add_reg_note (last, REG_CALL_DECL, datum);
4094 }
4095
4096 /* If the call setup or the call itself overlaps with anything
4097 of the argument setup we probably clobbered our call address.
4098 In that case we can't do sibcalls. */
4099 if (pass == 0
4100 && check_sibcall_argument_overlap (after_args, 0, 0))
4101 sibcall_failure = 1;
4102
4103 /* If a non-BLKmode value is returned at the most significant end
4104 of a register, shift the register right by the appropriate amount
4105 and update VALREG accordingly. BLKmode values are handled by the
4106 group load/store machinery below. */
4107 if (!structure_value_addr
4108 && !pcc_struct_value
4109 && TYPE_MODE (rettype) != VOIDmode
4110 && TYPE_MODE (rettype) != BLKmode
4111 && REG_P (valreg)
4112 && targetm.calls.return_in_msb (rettype))
4113 {
4114 if (shift_return_value (TYPE_MODE (rettype), false, valreg))
4115 sibcall_failure = 1;
4116 valreg = gen_rtx_REG (TYPE_MODE (rettype), REGNO (valreg));
4117 }
4118
4119 if (pass && (flags & ECF_MALLOC))
4120 {
4121 rtx temp = gen_reg_rtx (GET_MODE (valreg));
4122 rtx_insn *last, *insns;
4123
4124 /* The return value from a malloc-like function is a pointer. */
4125 if (TREE_CODE (rettype) == POINTER_TYPE)
4126 mark_reg_pointer (temp, MALLOC_ABI_ALIGNMENT);
4127
4128 emit_move_insn (temp, valreg);
4129
4130 /* The return value from a malloc-like function can not alias
4131 anything else. */
4132 last = get_last_insn ();
4133 add_reg_note (last, REG_NOALIAS, temp);
4134
4135 /* Write out the sequence. */
4136 insns = get_insns ();
4137 end_sequence ();
4138 emit_insn (insns);
4139 valreg = temp;
4140 }
4141
4142 /* For calls to `setjmp', etc., inform
4143 function.c:setjmp_warnings that it should complain if
4144 nonvolatile values are live. For functions that cannot
4145 return, inform flow that control does not fall through. */
4146
4147 if ((flags & ECF_NORETURN) || pass == 0)
4148 {
4149 /* The barrier must be emitted
4150 immediately after the CALL_INSN. Some ports emit more
4151 than just a CALL_INSN above, so we must search for it here. */
4152
4153 rtx_insn *last = get_last_insn ();
4154 while (!CALL_P (last))
4155 {
4156 last = PREV_INSN (last);
4157 /* There was no CALL_INSN? */
4158 gcc_assert (last != before_call);
4159 }
4160
4161 emit_barrier_after (last);
4162
4163 /* Stack adjustments after a noreturn call are dead code.
4164 However when NO_DEFER_POP is in effect, we must preserve
4165 stack_pointer_delta. */
4166 if (inhibit_defer_pop == 0)
4167 {
4168 stack_pointer_delta = old_stack_allocated;
4169 pending_stack_adjust = 0;
4170 }
4171 }
4172
4173 /* If value type not void, return an rtx for the value. */
4174
4175 if (TYPE_MODE (rettype) == VOIDmode
4176 || ignore)
4177 target = const0_rtx;
4178 else if (structure_value_addr)
4179 {
4180 if (target == 0 || !MEM_P (target))
4181 {
4182 target
4183 = gen_rtx_MEM (TYPE_MODE (rettype),
4184 memory_address (TYPE_MODE (rettype),
4185 structure_value_addr));
4186 set_mem_attributes (target, rettype, 1);
4187 }
4188 }
4189 else if (pcc_struct_value)
4190 {
4191 /* This is the special C++ case where we need to
4192 know what the true target was. We take care to
4193 never use this value more than once in one expression. */
4194 target = gen_rtx_MEM (TYPE_MODE (rettype),
4195 copy_to_reg (valreg));
4196 set_mem_attributes (target, rettype, 1);
4197 }
4198 /* Handle calls that return values in multiple non-contiguous locations.
4199 The Irix 6 ABI has examples of this. */
4200 else if (GET_CODE (valreg) == PARALLEL)
4201 {
4202 if (target == 0)
4203 target = emit_group_move_into_temps (valreg);
4204 else if (rtx_equal_p (target, valreg))
4205 ;
4206 else if (GET_CODE (target) == PARALLEL)
4207 /* Handle the result of a emit_group_move_into_temps
4208 call in the previous pass. */
4209 emit_group_move (target, valreg);
4210 else
4211 emit_group_store (target, valreg, rettype,
4212 int_size_in_bytes (rettype));
4213 }
4214 else if (target
4215 && GET_MODE (target) == TYPE_MODE (rettype)
4216 && GET_MODE (target) == GET_MODE (valreg))
4217 {
4218 bool may_overlap = false;
4219
4220 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
4221 reg to a plain register. */
4222 if (!REG_P (target) || HARD_REGISTER_P (target))
4223 valreg = avoid_likely_spilled_reg (valreg);
4224
4225 /* If TARGET is a MEM in the argument area, and we have
4226 saved part of the argument area, then we can't store
4227 directly into TARGET as it may get overwritten when we
4228 restore the argument save area below. Don't work too
4229 hard though and simply force TARGET to a register if it
4230 is a MEM; the optimizer is quite likely to sort it out. */
4231 if (ACCUMULATE_OUTGOING_ARGS && pass && MEM_P (target))
4232 for (i = 0; i < num_actuals; i++)
4233 if (args[i].save_area)
4234 {
4235 may_overlap = true;
4236 break;
4237 }
4238
4239 if (may_overlap)
4240 target = copy_to_reg (valreg);
4241 else
4242 {
4243 /* TARGET and VALREG cannot be equal at this point
4244 because the latter would not have
4245 REG_FUNCTION_VALUE_P true, while the former would if
4246 it were referring to the same register.
4247
4248 If they refer to the same register, this move will be
4249 a no-op, except when function inlining is being
4250 done. */
4251 emit_move_insn (target, valreg);
4252
4253 /* If we are setting a MEM, this code must be executed.
4254 Since it is emitted after the call insn, sibcall
4255 optimization cannot be performed in that case. */
4256 if (MEM_P (target))
4257 sibcall_failure = 1;
4258 }
4259 }
4260 else
4261 target = copy_to_reg (avoid_likely_spilled_reg (valreg));
4262
4263 /* If we promoted this return value, make the proper SUBREG.
4264 TARGET might be const0_rtx here, so be careful. */
4265 if (REG_P (target)
4266 && TYPE_MODE (rettype) != BLKmode
4267 && GET_MODE (target) != TYPE_MODE (rettype))
4268 {
4269 tree type = rettype;
4270 int unsignedp = TYPE_UNSIGNED (type);
4271 machine_mode pmode;
4272
4273 /* Ensure we promote as expected, and get the new unsignedness. */
4274 pmode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
4275 funtype, 1);
4276 gcc_assert (GET_MODE (target) == pmode);
4277
4278 unsigned int offset = subreg_lowpart_offset (TYPE_MODE (type),
4279 GET_MODE (target));
4280 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
4281 SUBREG_PROMOTED_VAR_P (target) = 1;
4282 SUBREG_PROMOTED_SET (target, unsignedp);
4283 }
4284
4285 /* If size of args is variable or this was a constructor call for a stack
4286 argument, restore saved stack-pointer value. */
4287
4288 if (old_stack_level)
4289 {
4290 rtx_insn *prev = get_last_insn ();
4291
4292 emit_stack_restore (SAVE_BLOCK, old_stack_level);
4293 stack_pointer_delta = old_stack_pointer_delta;
4294
4295 fixup_args_size_notes (prev, get_last_insn (), stack_pointer_delta);
4296
4297 pending_stack_adjust = old_pending_adj;
4298 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
4299 stack_arg_under_construction = old_stack_arg_under_construction;
4300 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4301 stack_usage_map = initial_stack_usage_map;
4302 sibcall_failure = 1;
4303 }
4304 else if (ACCUMULATE_OUTGOING_ARGS && pass)
4305 {
4306#ifdef REG_PARM_STACK_SPACE
4307 if (save_area)
4308 restore_fixed_argument_area (save_area, argblock,
4309 high_to_save, low_to_save);
4310#endif
4311
4312 /* If we saved any argument areas, restore them. */
4313 for (i = 0; i < num_actuals; i++)
4314 if (args[i].save_area)
4315 {
4316 machine_mode save_mode = GET_MODE (args[i].save_area);
4317 rtx stack_area
4318 = gen_rtx_MEM (save_mode,
4319 memory_address (save_mode,
4320 XEXP (args[i].stack_slot, 0)));
4321
4322 if (save_mode != BLKmode)
4323 emit_move_insn (stack_area, args[i].save_area);
4324 else
4325 emit_block_move (stack_area, args[i].save_area,
4326 GEN_INT (args[i].locate.size.constant),
4327 BLOCK_OP_CALL_PARM);
4328 }
4329
4330 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4331 stack_usage_map = initial_stack_usage_map;
4332 }
4333
4334 /* If this was alloca, record the new stack level. */
4335 if (flags & ECF_MAY_BE_ALLOCA)
4336 record_new_stack_level ();
4337
4338 /* Free up storage we no longer need. */
4339 for (i = 0; i < num_actuals; ++i)
4340 free (args[i].aligned_regs);
4341
4342 targetm.calls.end_call_args ();
4343
4344 insns = get_insns ();
4345 end_sequence ();
4346
4347 if (pass == 0)
4348 {
4349 tail_call_insns = insns;
4350
4351 /* Restore the pending stack adjustment now that we have
4352 finished generating the sibling call sequence. */
4353
4354 restore_pending_stack_adjust (&save);
4355
4356 /* Prepare arg structure for next iteration. */
4357 for (i = 0; i < num_actuals; i++)
4358 {
4359 args[i].value = 0;
4360 args[i].aligned_regs = 0;
4361 args[i].stack = 0;
4362 }
4363
4364 sbitmap_free (stored_args_map);
4365 internal_arg_pointer_exp_state.scan_start = NULL;
4366 internal_arg_pointer_exp_state.cache.release ();
4367 }
4368 else
4369 {
4370 normal_call_insns = insns;
4371
4372 /* Verify that we've deallocated all the stack we used. */
4373 gcc_assert ((flags & ECF_NORETURN)
4374 || (old_stack_allocated
4375 == stack_pointer_delta - pending_stack_adjust));
4376 }
4377
4378 /* If something prevents making this a sibling call,
4379 zero out the sequence. */
4380 if (sibcall_failure)
4381 tail_call_insns = NULL;
4382 else
4383 break;
4384 }
4385
4386 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
4387 arguments too, as argument area is now clobbered by the call. */
4388 if (tail_call_insns)
4389 {
4390 emit_insn (tail_call_insns);
4391 crtl->tail_call_emit = true;
4392 }
4393 else
4394 {
4395 emit_insn (normal_call_insns);
4396 if (try_tail_call)
4397 /* Ideally we'd emit a message for all of the ways that it could
4398 have failed. */
4399 maybe_complain_about_tail_call (exp, "tail call production failed");
4400 }
4401
4402 currently_expanding_call--;
4403
4404 free (stack_usage_map_buf);
4405 free (args);
4406
4407 /* Join result with returned bounds so caller may use them if needed. */
4408 target = chkp_join_splitted_slot (target, valbnd);
4409
4410 return target;
4411}
4412
4413/* A sibling call sequence invalidates any REG_EQUIV notes made for
4414 this function's incoming arguments.
4415
4416 At the start of RTL generation we know the only REG_EQUIV notes
4417 in the rtl chain are those for incoming arguments, so we can look
4418 for REG_EQUIV notes between the start of the function and the
4419 NOTE_INSN_FUNCTION_BEG.
4420
4421 This is (slight) overkill. We could keep track of the highest
4422 argument we clobber and be more selective in removing notes, but it
4423 does not seem to be worth the effort. */
4424
4425void
4426fixup_tail_calls (void)
4427{
4428 rtx_insn *insn;
4429
4430 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4431 {
4432 rtx note;
4433
4434 /* There are never REG_EQUIV notes for the incoming arguments
4435 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
4436 if (NOTE_P (insn)
4437 && NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG)
4438 break;
4439
4440 note = find_reg_note (insn, REG_EQUIV, 0);
4441 if (note)
4442 remove_note (insn, note);
4443 note = find_reg_note (insn, REG_EQUIV, 0);
4444 gcc_assert (!note);
4445 }
4446}
4447
4448/* Traverse a list of TYPES and expand all complex types into their
4449 components. */
4450static tree
4451split_complex_types (tree types)
4452{
4453 tree p;
4454
4455 /* Before allocating memory, check for the common case of no complex. */
4456 for (p = types; p; p = TREE_CHAIN (p))
4457 {
4458 tree type = TREE_VALUE (p);
4459 if (TREE_CODE (type) == COMPLEX_TYPE
4460 && targetm.calls.split_complex_arg (type))
4461 goto found;
4462 }
4463 return types;
4464
4465 found:
4466 types = copy_list (types);
4467
4468 for (p = types; p; p = TREE_CHAIN (p))
4469 {
4470 tree complex_type = TREE_VALUE (p);
4471
4472 if (TREE_CODE (complex_type) == COMPLEX_TYPE
4473 && targetm.calls.split_complex_arg (complex_type))
4474 {
4475 tree next, imag;
4476
4477 /* Rewrite complex type with component type. */
4478 TREE_VALUE (p) = TREE_TYPE (complex_type);
4479 next = TREE_CHAIN (p);
4480
4481 /* Add another component type for the imaginary part. */
4482 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
4483 TREE_CHAIN (p) = imag;
4484 TREE_CHAIN (imag) = next;
4485
4486 /* Skip the newly created node. */
4487 p = TREE_CHAIN (p);
4488 }
4489 }
4490
4491 return types;
4492}
4493
4494/* Output a library call to function ORGFUN (a SYMBOL_REF rtx)
4495 for a value of mode OUTMODE,
4496 with NARGS different arguments, passed as ARGS.
4497 Store the return value if RETVAL is nonzero: store it in VALUE if
4498 VALUE is nonnull, otherwise pick a convenient location. In either
4499 case return the location of the stored value.
4500
4501 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
4502 `const' calls, LCT_PURE for `pure' calls, or another LCT_ value for
4503 other types of library calls. */
4504
4505rtx
4506emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
4507 enum libcall_type fn_type,
4508 machine_mode outmode, int