1 /*
2 * Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "gc/shared/barrierSet.hpp"
27 #include "gc/shared/c2/barrierSetC2.hpp"
28 #include "gc/shared/c2/cardTableBarrierSetC2.hpp"
29 #include "opto/arraycopynode.hpp"
30 #include "opto/graphKit.hpp"
31 #include "runtime/sharedRuntime.hpp"
32 #include "utilities/macros.hpp"
33
34 ArrayCopyNode::ArrayCopyNode(Compile* C, bool alloc_tightly_coupled, bool has_negative_length_guard)
35 : CallNode(arraycopy_type(), NULL, TypePtr::BOTTOM),
36 _kind(None),
37 _alloc_tightly_coupled(alloc_tightly_coupled),
38 _has_negative_length_guard(has_negative_length_guard),
39 _arguments_validated(false),
40 _src_type(TypeOopPtr::BOTTOM),
41 _dest_type(TypeOopPtr::BOTTOM) {
42 init_class_id(Class_ArrayCopy);
43 init_flags(Flag_is_macro);
44 C->add_macro_node(this);
45 }
46
47 uint ArrayCopyNode::size_of() const { return sizeof(*this); }
48
49 ArrayCopyNode* ArrayCopyNode::make(GraphKit* kit, bool may_throw,
50 Node* src, Node* src_offset,
51 Node* dest, Node* dest_offset,
52 Node* length,
53 bool alloc_tightly_coupled,
54 bool has_negative_length_guard,
55 Node* src_klass, Node* dest_klass,
56 Node* src_length, Node* dest_length) {
57
58 ArrayCopyNode* ac = new ArrayCopyNode(kit->C, alloc_tightly_coupled, has_negative_length_guard);
59 Node* prev_mem = kit->set_predefined_input_for_runtime_call(ac);
60
61 ac->init_req(ArrayCopyNode::Src, src);
62 ac->init_req(ArrayCopyNode::SrcPos, src_offset);
63 ac->init_req(ArrayCopyNode::Dest, dest);
64 ac->init_req(ArrayCopyNode::DestPos, dest_offset);
65 ac->init_req(ArrayCopyNode::Length, length);
66 ac->init_req(ArrayCopyNode::SrcLen, src_length);
67 ac->init_req(ArrayCopyNode::DestLen, dest_length);
68 ac->init_req(ArrayCopyNode::SrcKlass, src_klass);
69 ac->init_req(ArrayCopyNode::DestKlass, dest_klass);
70
71 if (may_throw) {
72 ac->set_req(TypeFunc::I_O , kit->i_o());
73 kit->add_safepoint_edges(ac, false);
74 }
75
76 return ac;
77 }
78
79 void ArrayCopyNode::connect_outputs(GraphKit* kit) {
80 kit->set_all_memory_call(this, true);
81 kit->set_control(kit->gvn().transform(new ProjNode(this,TypeFunc::Control)));
82 kit->set_i_o(kit->gvn().transform(new ProjNode(this, TypeFunc::I_O)));
83 kit->make_slow_call_ex(this, kit->env()->Throwable_klass(), true);
84 kit->set_all_memory_call(this);
85 }
86
87 #ifndef PRODUCT
88 const char* ArrayCopyNode::_kind_names[] = {"arraycopy", "arraycopy, validated arguments", "clone", "oop array clone", "CopyOf", "CopyOfRange"};
89
90 void ArrayCopyNode::dump_spec(outputStream *st) const {
91 CallNode::dump_spec(st);
92 st->print(" (%s%s)", _kind_names[_kind], _alloc_tightly_coupled ? ", tightly coupled allocation" : "");
93 }
94
95 void ArrayCopyNode::dump_compact_spec(outputStream* st) const {
96 st->print("%s%s", _kind_names[_kind], _alloc_tightly_coupled ? ",tight" : "");
97 }
98 #endif
99
100 intptr_t ArrayCopyNode::get_length_if_constant(PhaseGVN *phase) const {
101 // check that length is constant
102 Node* length = in(ArrayCopyNode::Length);
103 const Type* length_type = phase->type(length);
104
105 if (length_type == Type::TOP) {
106 return -1;
107 }
108
109 assert(is_clonebasic() || is_arraycopy() || is_copyof() || is_copyofrange(), "unexpected array copy type");
110
111 return is_clonebasic() ? length->find_intptr_t_con(-1) : length->find_int_con(-1);
112 }
113
114 int ArrayCopyNode::get_count(PhaseGVN *phase) const {
115 Node* src = in(ArrayCopyNode::Src);
116 const Type* src_type = phase->type(src);
117
118 if (is_clonebasic()) {
119 if (src_type->isa_instptr()) {
120 const TypeInstPtr* inst_src = src_type->is_instptr();
121 ciInstanceKlass* ik = inst_src->klass()->as_instance_klass();
122 // ciInstanceKlass::nof_nonstatic_fields() doesn't take injected
123 // fields into account. They are rare anyway so easier to simply
124 // skip instances with injected fields.
125 if ((!inst_src->klass_is_exact() && (ik->is_interface() || ik->has_subklass())) || ik->has_injected_fields()) {
126 return -1;
127 }
128 int nb_fields = ik->nof_nonstatic_fields();
129 return nb_fields;
130 } else {
131 const TypeAryPtr* ary_src = src_type->isa_aryptr();
132 assert (ary_src != NULL, "not an array or instance?");
133 // clone passes a length as a rounded number of longs. If we're
134 // cloning an array we'll do it element by element. If the
135 // length input to ArrayCopyNode is constant, length of input
136 // array must be too.
137
138 assert((get_length_if_constant(phase) == -1) == !ary_src->size()->is_con() ||
139 phase->is_IterGVN(), "inconsistent");
140
141 if (ary_src->size()->is_con()) {
142 return ary_src->size()->get_con();
143 }
144 return -1;
145 }
146 }
147
148 return get_length_if_constant(phase);
149 }
150
151 Node* ArrayCopyNode::load(PhaseGVN *phase, Node*& ctl, MergeMemNode* mem, Node* adr, const TypePtr* adr_type, const Type *type, BasicType bt) {
152 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
153 DecoratorSet decorators = C2_READ_ACCESS | C2_CONTROL_DEPENDENT_LOAD | IN_HEAP | C2_ARRAY_COPY;
154 C2AccessValuePtr addr(adr, adr_type);
155 C2OptAccess access(*phase, ctl, mem, decorators, bt, adr->in(AddPNode::Base), addr);
156 Node* res = bs->load_at(access, type);
157 ctl = access.ctl();
158 return res;
159 }
160
161 void ArrayCopyNode::store(PhaseGVN *phase, Node*& ctl, MergeMemNode* mem, Node* adr, const TypePtr* adr_type, Node* val, const Type *type, BasicType bt) {
162 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
163 DecoratorSet decorators = C2_WRITE_ACCESS | IN_HEAP | C2_ARRAY_COPY;
164 if (is_alloc_tightly_coupled()) {
165 decorators |= C2_TIGHLY_COUPLED_ALLOC;
166 }
167 C2AccessValuePtr addr(adr, adr_type);
168 C2AccessValue value(val, type);
169 C2OptAccess access(*phase, ctl, mem, decorators, bt, adr->in(AddPNode::Base), addr);
170 bs->store_at(access, value);
171 ctl = access.ctl();
172 }
173
174
175 Node* ArrayCopyNode::try_clone_instance(PhaseGVN *phase, bool can_reshape, int count) {
176 if (!is_clonebasic()) {
177 return NULL;
178 }
179
180 Node* src = in(ArrayCopyNode::Src);
181 Node* dest = in(ArrayCopyNode::Dest);
182 Node* ctl = in(TypeFunc::Control);
183 Node* in_mem = in(TypeFunc::Memory);
184
185 const Type* src_type = phase->type(src);
186
187 assert(src->is_AddP(), "should be base + off");
188 assert(dest->is_AddP(), "should be base + off");
189 Node* base_src = src->in(AddPNode::Base);
190 Node* base_dest = dest->in(AddPNode::Base);
191
192 MergeMemNode* mem = MergeMemNode::make(in_mem);
193
194 const TypeInstPtr* inst_src = src_type->isa_instptr();
195
196 if (inst_src == NULL) {
197 return NULL;
198 }
199
200 if (!inst_src->klass_is_exact()) {
201 ciInstanceKlass* ik = inst_src->klass()->as_instance_klass();
202 assert(!ik->is_interface() && !ik->has_subklass(), "inconsistent klass hierarchy");
203 phase->C->dependencies()->assert_leaf_type(ik);
204 }
205
206 ciInstanceKlass* ik = inst_src->klass()->as_instance_klass();
207 assert(ik->nof_nonstatic_fields() <= ArrayCopyLoadStoreMaxElem, "too many fields");
208
209 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
210 for (int i = 0; i < count; i++) {
211 ciField* field = ik->nonstatic_field_at(i);
212 int fieldidx = phase->C->alias_type(field)->index();
213 const TypePtr* adr_type = phase->C->alias_type(field)->adr_type();
214 Node* off = phase->MakeConX(field->offset());
215 Node* next_src = phase->transform(new AddPNode(base_src,base_src,off));
216 Node* next_dest = phase->transform(new AddPNode(base_dest,base_dest,off));
217 BasicType bt = field->layout_type();
218
219 const Type *type;
220 if (bt == T_OBJECT) {
221 if (!field->type()->is_loaded()) {
222 type = TypeInstPtr::BOTTOM;
223 } else {
224 ciType* field_klass = field->type();
225 type = TypeOopPtr::make_from_klass(field_klass->as_klass());
226 }
227 } else {
228 type = Type::get_const_basic_type(bt);
229 }
230
231 Node* v = load(phase, ctl, mem, next_src, adr_type, type, bt);
232 store(phase, ctl, mem, next_dest, adr_type, v, type, bt);
233 }
234
235 if (!finish_transform(phase, can_reshape, ctl, mem)) {
236 // Return NodeSentinel to indicate that the transform failed
237 return NodeSentinel;
238 }
239
240 return mem;
241 }
242
243 bool ArrayCopyNode::prepare_array_copy(PhaseGVN *phase, bool can_reshape,
244 Node*& adr_src,
245 Node*& base_src,
246 Node*& adr_dest,
247 Node*& base_dest,
248 BasicType& copy_type,
249 const Type*& value_type,
250 bool& disjoint_bases) {
251 Node* src = in(ArrayCopyNode::Src);
252 Node* dest = in(ArrayCopyNode::Dest);
253 const Type* src_type = phase->type(src);
254 const TypeAryPtr* ary_src = src_type->isa_aryptr();
255
256 if (is_arraycopy() || is_copyofrange() || is_copyof()) {
257 const Type* dest_type = phase->type(dest);
258 const TypeAryPtr* ary_dest = dest_type->isa_aryptr();
259 Node* src_offset = in(ArrayCopyNode::SrcPos);
260 Node* dest_offset = in(ArrayCopyNode::DestPos);
261
262 // newly allocated object is guaranteed to not overlap with source object
263 disjoint_bases = is_alloc_tightly_coupled();
264
265 if (ary_src == NULL || ary_src->klass() == NULL ||
266 ary_dest == NULL || ary_dest->klass() == NULL) {
267 // We don't know if arguments are arrays
268 return false;
269 }
270
271 BasicType src_elem = ary_src->klass()->as_array_klass()->element_type()->basic_type();
272 BasicType dest_elem = ary_dest->klass()->as_array_klass()->element_type()->basic_type();
273 if (src_elem == T_ARRAY) src_elem = T_OBJECT;
274 if (dest_elem == T_ARRAY) dest_elem = T_OBJECT;
275
276 if (src_elem != dest_elem || dest_elem == T_VOID) {
277 // We don't know if arguments are arrays of the same type
278 return false;
279 }
280
281 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
282 if (bs->array_copy_requires_gc_barriers(is_alloc_tightly_coupled(), dest_elem, false, BarrierSetC2::Optimization)) {
283 // It's an object array copy but we can't emit the card marking
284 // that is needed
285 return false;
286 }
287
288 value_type = ary_src->elem();
289
290 base_src = src;
291 base_dest = dest;
292
293 uint shift = exact_log2(type2aelembytes(dest_elem));
294 uint header = arrayOopDesc::base_offset_in_bytes(dest_elem);
295
296 adr_src = src;
297 adr_dest = dest;
298
299 src_offset = Compile::conv_I2X_index(phase, src_offset, ary_src->size());
300 dest_offset = Compile::conv_I2X_index(phase, dest_offset, ary_dest->size());
301
302 Node* src_scale = phase->transform(new LShiftXNode(src_offset, phase->intcon(shift)));
303 Node* dest_scale = phase->transform(new LShiftXNode(dest_offset, phase->intcon(shift)));
304
305 adr_src = phase->transform(new AddPNode(base_src, adr_src, src_scale));
306 adr_dest = phase->transform(new AddPNode(base_dest, adr_dest, dest_scale));
307
308 adr_src = new AddPNode(base_src, adr_src, phase->MakeConX(header));
309 adr_dest = new AddPNode(base_dest, adr_dest, phase->MakeConX(header));
310
311 adr_src = phase->transform(adr_src);
312 adr_dest = phase->transform(adr_dest);
313
314 copy_type = dest_elem;
315 } else {
316 assert(ary_src != NULL, "should be a clone");
317 assert(is_clonebasic(), "should be");
318
319 disjoint_bases = true;
320 assert(src->is_AddP(), "should be base + off");
321 assert(dest->is_AddP(), "should be base + off");
322 adr_src = src;
323 base_src = src->in(AddPNode::Base);
324 adr_dest = dest;
325 base_dest = dest->in(AddPNode::Base);
326
327 assert(phase->type(src->in(AddPNode::Offset))->is_intptr_t()->get_con() == phase->type(dest->in(AddPNode::Offset))->is_intptr_t()->get_con(), "same start offset?");
328 BasicType elem = ary_src->klass()->as_array_klass()->element_type()->basic_type();
329 if (elem == T_ARRAY) elem = T_OBJECT;
330
331 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
332 if (bs->array_copy_requires_gc_barriers(true, elem, true, BarrierSetC2::Optimization)) {
333 return false;
334 }
335
336 int diff = arrayOopDesc::base_offset_in_bytes(elem) - phase->type(src->in(AddPNode::Offset))->is_intptr_t()->get_con();
337 assert(diff >= 0, "clone should not start after 1st array element");
338 if (diff > 0) {
339 adr_src = phase->transform(new AddPNode(base_src, adr_src, phase->MakeConX(diff)));
340 adr_dest = phase->transform(new AddPNode(base_dest, adr_dest, phase->MakeConX(diff)));
341 }
342
343 copy_type = elem;
344 value_type = ary_src->elem();
345 }
346 return true;
347 }
348
349 const TypePtr* ArrayCopyNode::get_address_type(PhaseGVN *phase, Node* n) {
350 const Type* at = phase->type(n);
351 assert(at != Type::TOP, "unexpected type");
352 const TypePtr* atp = at->isa_ptr();
353 // adjust atp to be the correct array element address type
354 atp = atp->add_offset(Type::OffsetBot);
355 return atp;
356 }
357
358 void ArrayCopyNode::array_copy_test_overlap(PhaseGVN *phase, bool can_reshape, bool disjoint_bases, int count, Node*& forward_ctl, Node*& backward_ctl) {
359 Node* ctl = in(TypeFunc::Control);
360 if (!disjoint_bases && count > 1) {
361 Node* src_offset = in(ArrayCopyNode::SrcPos);
362 Node* dest_offset = in(ArrayCopyNode::DestPos);
363 assert(src_offset != NULL && dest_offset != NULL, "should be");
364 Node* cmp = phase->transform(new CmpINode(src_offset, dest_offset));
365 Node *bol = phase->transform(new BoolNode(cmp, BoolTest::lt));
366 IfNode *iff = new IfNode(ctl, bol, PROB_FAIR, COUNT_UNKNOWN);
367
368 phase->transform(iff);
369
370 forward_ctl = phase->transform(new IfFalseNode(iff));
371 backward_ctl = phase->transform(new IfTrueNode(iff));
372 } else {
373 forward_ctl = ctl;
374 }
375 }
376
377 Node* ArrayCopyNode::array_copy_forward(PhaseGVN *phase,
378 bool can_reshape,
379 Node*& forward_ctl,
380 MergeMemNode* mm,
381 const TypePtr* atp_src,
382 const TypePtr* atp_dest,
383 Node* adr_src,
384 Node* base_src,
385 Node* adr_dest,
386 Node* base_dest,
387 BasicType copy_type,
388 const Type* value_type,
389 int count) {
390 if (!forward_ctl->is_top()) {
391 // copy forward
392 mm = mm->clone()->as_MergeMem();
393
394 if (count > 0) {
395 Node* v = load(phase, forward_ctl, mm, adr_src, atp_src, value_type, copy_type);
396 store(phase, forward_ctl, mm, adr_dest, atp_dest, v, value_type, copy_type);
397 for (int i = 1; i < count; i++) {
398 Node* off = phase->MakeConX(type2aelembytes(copy_type) * i);
399 Node* next_src = phase->transform(new AddPNode(base_src,adr_src,off));
400 Node* next_dest = phase->transform(new AddPNode(base_dest,adr_dest,off));
401 v = load(phase, forward_ctl, mm, next_src, atp_src, value_type, copy_type);
402 store(phase, forward_ctl, mm, next_dest, atp_dest, v, value_type, copy_type);
403 }
404 } else if(can_reshape) {
405 PhaseIterGVN* igvn = phase->is_IterGVN();
406 igvn->_worklist.push(adr_src);
407 igvn->_worklist.push(adr_dest);
408 }
409 return mm;
410 }
411 return phase->C->top();
412 }
413
414 Node* ArrayCopyNode::array_copy_backward(PhaseGVN *phase,
415 bool can_reshape,
416 Node*& backward_ctl,
417 MergeMemNode* mm,
418 const TypePtr* atp_src,
419 const TypePtr* atp_dest,
420 Node* adr_src,
421 Node* base_src,
422 Node* adr_dest,
423 Node* base_dest,
424 BasicType copy_type,
425 const Type* value_type,
426 int count) {
427 if (!backward_ctl->is_top()) {
428 // copy backward
429 mm = mm->clone()->as_MergeMem();
430
431 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
432 assert(copy_type != T_OBJECT || !bs->array_copy_requires_gc_barriers(false, T_OBJECT, false, BarrierSetC2::Optimization), "only tightly coupled allocations for object arrays");
433
434 if (count > 0) {
435 for (int i = count-1; i >= 1; i--) {
436 Node* off = phase->MakeConX(type2aelembytes(copy_type) * i);
437 Node* next_src = phase->transform(new AddPNode(base_src,adr_src,off));
438 Node* next_dest = phase->transform(new AddPNode(base_dest,adr_dest,off));
439 Node* v = load(phase, backward_ctl, mm, next_src, atp_src, value_type, copy_type);
440 store(phase, backward_ctl, mm, next_dest, atp_dest, v, value_type, copy_type);
441 }
442 Node* v = load(phase, backward_ctl, mm, adr_src, atp_src, value_type, copy_type);
443 store(phase, backward_ctl, mm, adr_dest, atp_dest, v, value_type, copy_type);
444 } else if(can_reshape) {
445 PhaseIterGVN* igvn = phase->is_IterGVN();
446 igvn->_worklist.push(adr_src);
447 igvn->_worklist.push(adr_dest);
448 }
449 return phase->transform(mm);
450 }
451 return phase->C->top();
452 }
453
454 bool ArrayCopyNode::finish_transform(PhaseGVN *phase, bool can_reshape,
455 Node* ctl, Node *mem) {
456 if (can_reshape) {
457 PhaseIterGVN* igvn = phase->is_IterGVN();
458 igvn->set_delay_transform(false);
459 if (is_clonebasic()) {
460 Node* out_mem = proj_out(TypeFunc::Memory);
461
462 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
463 if (out_mem->outcnt() != 1 || !out_mem->raw_out(0)->is_MergeMem() ||
464 out_mem->raw_out(0)->outcnt() != 1 || !out_mem->raw_out(0)->raw_out(0)->is_MemBar()) {
465 assert(bs->array_copy_requires_gc_barriers(true, T_OBJECT, true, BarrierSetC2::Optimization), "can only happen with card marking");
466 return false;
467 }
468
469 igvn->replace_node(out_mem->raw_out(0), mem);
470
471 Node* out_ctl = proj_out(TypeFunc::Control);
472 igvn->replace_node(out_ctl, ctl);
473 } else {
474 // replace fallthrough projections of the ArrayCopyNode by the
475 // new memory, control and the input IO.
476 CallProjections callprojs;
477 extract_projections(&callprojs, true, false);
478
479 if (callprojs.fallthrough_ioproj != NULL) {
480 igvn->replace_node(callprojs.fallthrough_ioproj, in(TypeFunc::I_O));
481 }
482 if (callprojs.fallthrough_memproj != NULL) {
483 igvn->replace_node(callprojs.fallthrough_memproj, mem);
484 }
485 if (callprojs.fallthrough_catchproj != NULL) {
486 igvn->replace_node(callprojs.fallthrough_catchproj, ctl);
487 }
488
489 // The ArrayCopyNode is not disconnected. It still has the
490 // projections for the exception case. Replace current
491 // ArrayCopyNode with a dummy new one with a top() control so
492 // that this part of the graph stays consistent but is
493 // eventually removed.
494
495 set_req(0, phase->C->top());
496 remove_dead_region(phase, can_reshape);
497 }
498 } else {
499 if (in(TypeFunc::Control) != ctl) {
500 // we can't return new memory and control from Ideal at parse time
501 assert(!is_clonebasic(), "added control for clone?");
502 phase->record_for_igvn(this);
503 return false;
504 }
505 }
506 return true;
507 }
508
509
510 Node *ArrayCopyNode::Ideal(PhaseGVN *phase, bool can_reshape) {
511 if (remove_dead_region(phase, can_reshape)) return this;
512
513 if (StressArrayCopyMacroNode && !can_reshape) {
514 phase->record_for_igvn(this);
515 return NULL;
516 }
517
518 // See if it's a small array copy and we can inline it as
519 // loads/stores
520 // Here we can only do:
521 // - arraycopy if all arguments were validated before and we don't
522 // need card marking
523 // - clone for which we don't need to do card marking
524
525 if (!is_clonebasic() && !is_arraycopy_validated() &&
526 !is_copyofrange_validated() && !is_copyof_validated()) {
527 return NULL;
528 }
529
530 assert(in(TypeFunc::Control) != NULL &&
531 in(TypeFunc::Memory) != NULL &&
532 in(ArrayCopyNode::Src) != NULL &&
533 in(ArrayCopyNode::Dest) != NULL &&
534 in(ArrayCopyNode::Length) != NULL &&
535 ((in(ArrayCopyNode::SrcPos) != NULL && in(ArrayCopyNode::DestPos) != NULL) ||
536 is_clonebasic()), "broken inputs");
537
538 if (in(TypeFunc::Control)->is_top() ||
539 in(TypeFunc::Memory)->is_top() ||
540 phase->type(in(ArrayCopyNode::Src)) == Type::TOP ||
541 phase->type(in(ArrayCopyNode::Dest)) == Type::TOP ||
542 (in(ArrayCopyNode::SrcPos) != NULL && in(ArrayCopyNode::SrcPos)->is_top()) ||
543 (in(ArrayCopyNode::DestPos) != NULL && in(ArrayCopyNode::DestPos)->is_top())) {
544 return NULL;
545 }
546
547 int count = get_count(phase);
548
549 if (count < 0 || count > ArrayCopyLoadStoreMaxElem) {
550 return NULL;
551 }
552
553 Node* mem = try_clone_instance(phase, can_reshape, count);
554 if (mem != NULL) {
555 return (mem == NodeSentinel) ? NULL : mem;
556 }
557
558 Node* adr_src = NULL;
559 Node* base_src = NULL;
560 Node* adr_dest = NULL;
561 Node* base_dest = NULL;
562 BasicType copy_type = T_ILLEGAL;
563 const Type* value_type = NULL;
564 bool disjoint_bases = false;
565
566 if (!prepare_array_copy(phase, can_reshape,
567 adr_src, base_src, adr_dest, base_dest,
568 copy_type, value_type, disjoint_bases)) {
569 return NULL;
570 }
571
572 Node* src = in(ArrayCopyNode::Src);
573 Node* dest = in(ArrayCopyNode::Dest);
574 const TypePtr* atp_src = get_address_type(phase, src);
575 const TypePtr* atp_dest = get_address_type(phase, dest);
576
577 Node *in_mem = in(TypeFunc::Memory);
578 if (!in_mem->is_MergeMem()) {
579 in_mem = MergeMemNode::make(in_mem);
580 }
581
582
583 if (can_reshape) {
584 assert(!phase->is_IterGVN()->delay_transform(), "cannot delay transforms");
585 phase->is_IterGVN()->set_delay_transform(true);
586 }
587
588 Node* backward_ctl = phase->C->top();
589 Node* forward_ctl = phase->C->top();
590 array_copy_test_overlap(phase, can_reshape, disjoint_bases, count, forward_ctl, backward_ctl);
591
592 Node* forward_mem = array_copy_forward(phase, can_reshape, forward_ctl,
593 in_mem->as_MergeMem(),
594 atp_src, atp_dest,
595 adr_src, base_src, adr_dest, base_dest,
596 copy_type, value_type, count);
597
598 Node* backward_mem = array_copy_backward(phase, can_reshape, backward_ctl,
599 in_mem->as_MergeMem(),
600 atp_src, atp_dest,
601 adr_src, base_src, adr_dest, base_dest,
602 copy_type, value_type, count);
603
604 Node* ctl = NULL;
605 if (!forward_ctl->is_top() && !backward_ctl->is_top()) {
606 ctl = new RegionNode(3);
607 ctl->init_req(1, forward_ctl);
608 ctl->init_req(2, backward_ctl);
609 ctl = phase->transform(ctl);
610 MergeMemNode* forward_mm = forward_mem->as_MergeMem();
611 MergeMemNode* backward_mm = backward_mem->as_MergeMem();
612 for (MergeMemStream mms(forward_mm, backward_mm); mms.next_non_empty2(); ) {
613 if (mms.memory() != mms.memory2()) {
614 Node* phi = new PhiNode(ctl, Type::MEMORY, phase->C->get_adr_type(mms.alias_idx()));
615 phi->init_req(1, mms.memory());
616 phi->init_req(2, mms.memory2());
617 phi = phase->transform(phi);
618 mms.set_memory(phi);
619 }
620 }
621 mem = forward_mem;
622 } else if (!forward_ctl->is_top()) {
623 ctl = forward_ctl;
624 mem = forward_mem;
625 } else {
626 assert(!backward_ctl->is_top(), "no copy?");
627 ctl = backward_ctl;
628 mem = backward_mem;
629 }
630
631 if (can_reshape) {
632 assert(phase->is_IterGVN()->delay_transform(), "should be delaying transforms");
633 phase->is_IterGVN()->set_delay_transform(false);
634 }
635
636 if (!finish_transform(phase, can_reshape, ctl, mem)) {
637 return NULL;
638 }
639
640 return mem;
641 }
642
643 bool ArrayCopyNode::may_modify(const TypeOopPtr *t_oop, PhaseTransform *phase) {
644 Node* dest = in(ArrayCopyNode::Dest);
645 if (dest->is_top()) {
646 return false;
647 }
648 const TypeOopPtr* dest_t = phase->type(dest)->is_oopptr();
649 assert(!dest_t->is_known_instance() || _dest_type->is_known_instance(), "result of EA not recorded");
650 assert(in(ArrayCopyNode::Src)->is_top() || !phase->type(in(ArrayCopyNode::Src))->is_oopptr()->is_known_instance() ||
651 _src_type->is_known_instance(), "result of EA not recorded");
652
653 if (_dest_type != TypeOopPtr::BOTTOM || t_oop->is_known_instance()) {
654 assert(_dest_type == TypeOopPtr::BOTTOM || _dest_type->is_known_instance(), "result of EA is known instance");
655 return t_oop->instance_id() == _dest_type->instance_id();
656 }
657
658 return CallNode::may_modify_arraycopy_helper(dest_t, t_oop, phase);
659 }
660
661 bool ArrayCopyNode::may_modify_helper(const TypeOopPtr *t_oop, Node* n, PhaseTransform *phase, CallNode*& call) {
662 if (n != NULL &&
663 n->is_Call() &&
664 n->as_Call()->may_modify(t_oop, phase) &&
665 (n->as_Call()->is_ArrayCopy() || n->as_Call()->is_call_to_arraycopystub())) {
666 call = n->as_Call();
667 return true;
668 }
669 return false;
670 }
671
672 bool ArrayCopyNode::may_modify(const TypeOopPtr *t_oop, MemBarNode* mb, PhaseTransform *phase, ArrayCopyNode*& ac) {
673
674 Node* c = mb->in(0);
675
676 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
677 // step over g1 gc barrier if we're at e.g. a clone with ReduceInitialCardMarks off
678 c = bs->step_over_gc_barrier(c);
679
680 CallNode* call = NULL;
681 guarantee(c != NULL, "step_over_gc_barrier failed, there must be something to step to.");
682 if (c->is_Region()) {
683 for (uint i = 1; i < c->req(); i++) {
684 if (c->in(i) != NULL) {
685 Node* n = c->in(i)->in(0);
686 if (may_modify_helper(t_oop, n, phase, call)) {
687 ac = call->isa_ArrayCopy();
688 assert(c == mb->in(0), "only for clone");
689 return true;
690 }
691 }
692 }
693 } else if (may_modify_helper(t_oop, c->in(0), phase, call)) {
694 ac = call->isa_ArrayCopy();
695 #ifdef ASSERT
696 bool use_ReduceInitialCardMarks = BarrierSet::barrier_set()->is_a(BarrierSet::CardTableBarrierSet) &&
697 static_cast<CardTableBarrierSetC2*>(bs)->use_ReduceInitialCardMarks();
698 assert(c == mb->in(0) || (ac != NULL && ac->is_clonebasic() && !use_ReduceInitialCardMarks), "only for clone");
699 #endif
700 return true;
701 }
702
703 return false;
704 }
705
706 // Does this array copy modify offsets between offset_lo and offset_hi
707 // in the destination array
708 // if must_modify is false, return true if the copy could write
709 // between offset_lo and offset_hi
710 // if must_modify is true, return true if the copy is guaranteed to
711 // write between offset_lo and offset_hi
712 bool ArrayCopyNode::modifies(intptr_t offset_lo, intptr_t offset_hi, PhaseTransform* phase, bool must_modify) const {
713 assert(_kind == ArrayCopy || _kind == CopyOf || _kind == CopyOfRange, "only for real array copies");
714
715 Node* dest = in(Dest);
716 Node* dest_pos = in(DestPos);
717 Node* len = in(Length);
718
719 const TypeInt *dest_pos_t = phase->type(dest_pos)->isa_int();
720 const TypeInt *len_t = phase->type(len)->isa_int();
721 const TypeAryPtr* ary_t = phase->type(dest)->isa_aryptr();
722
723 if (dest_pos_t == NULL || len_t == NULL || ary_t == NULL) {
724 return !must_modify;
725 }
726
727 BasicType ary_elem = ary_t->klass()->as_array_klass()->element_type()->basic_type();
728 uint header = arrayOopDesc::base_offset_in_bytes(ary_elem);
729 uint elemsize = type2aelembytes(ary_elem);
730
731 jlong dest_pos_plus_len_lo = (((jlong)dest_pos_t->_lo) + len_t->_lo) * elemsize + header;
732 jlong dest_pos_plus_len_hi = (((jlong)dest_pos_t->_hi) + len_t->_hi) * elemsize + header;
733 jlong dest_pos_lo = ((jlong)dest_pos_t->_lo) * elemsize + header;
734 jlong dest_pos_hi = ((jlong)dest_pos_t->_hi) * elemsize + header;
735
736 if (must_modify) {
737 if (offset_lo >= dest_pos_hi && offset_hi < dest_pos_plus_len_lo) {
738 return true;
739 }
740 } else {
741 if (offset_hi >= dest_pos_lo && offset_lo < dest_pos_plus_len_hi) {
742 return true;
743 }
744 }
745 return false;
746 }