1 /*
2 * Copyright (c) 2015, Red Hat, Inc. and/or its affiliates.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation.
7 *
8 * This code is distributed in the hope that it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
11 * version 2 for more details (a copy is included in the LICENSE file that
12 * accompanied this code).
13 *
14 * You should have received a copy of the GNU General Public License version
15 * 2 along with this work; if not, write to the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
17 *
18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
19 * or visit www.oracle.com if you need additional information or have any
20 * questions.
21 *
22 */
23
24 #include "precompiled.hpp"
25 #include "gc/shenandoah/brooksPointer.hpp"
26 #include "gc/shenandoah/shenandoahHeap.hpp"
27 #include "gc/shenandoah/shenandoahHeapRegion.hpp"
28 #include "opto/arraycopynode.hpp"
29 #include "opto/block.hpp"
30 #include "opto/callnode.hpp"
31 #include "opto/castnode.hpp"
32 #include "opto/movenode.hpp"
33 #include "opto/phaseX.hpp"
34 #include "opto/rootnode.hpp"
35 #include "opto/runtime.hpp"
36 #include "opto/shenandoahSupport.hpp"
37 #include "opto/subnode.hpp"
38
39 Node* ShenandoahBarrierNode::skip_through_barrier(Node* n) {
40 if (n == NULL) {
41 return NULL;
42 } else if (n->is_ShenandoahBarrier()) {
43 return n->in(ValueIn);
44 } else if (n->is_Phi() &&
45 n->req() == 3 &&
46 n->in(1) != NULL &&
47 n->in(1)->is_ShenandoahBarrier() &&
48 n->in(2) != NULL &&
49 n->in(2)->bottom_type() == TypePtr::NULL_PTR &&
50 n->in(0) != NULL &&
51 n->in(0)->in(1) != NULL &&
52 n->in(0)->in(1)->is_IfProj() &&
53 n->in(0)->in(2) != NULL &&
54 n->in(0)->in(2)->is_IfProj() &&
55 n->in(0)->in(1)->in(0) != NULL &&
56 n->in(0)->in(1)->in(0) == n->in(0)->in(2)->in(0) &&
57 n->in(1)->in(ValueIn)->Opcode() == Op_CastPP) {
58 Node* iff = n->in(0)->in(1)->in(0);
59 Node* res = n->in(1)->in(ValueIn)->in(1);
60 if (iff->is_If() &&
61 iff->in(1) != NULL &&
62 iff->in(1)->is_Bool() &&
63 iff->in(1)->as_Bool()->_test._test == BoolTest::ne &&
64 iff->in(1)->in(1) != NULL &&
65 iff->in(1)->in(1)->Opcode() == Op_CmpP &&
66 iff->in(1)->in(1)->in(1) != NULL &&
67 iff->in(1)->in(1)->in(1) == res &&
68 iff->in(1)->in(1)->in(2) != NULL &&
69 iff->in(1)->in(1)->in(2)->bottom_type() == TypePtr::NULL_PTR) {
70 return res;
71 }
72 }
73 return n;
74 }
75
76 bool ShenandoahBarrierNode::needs_barrier(PhaseGVN* phase, ShenandoahBarrierNode* orig, Node* n, Node* rb_mem, bool allow_fromspace) {
77 Unique_Node_List visited;
78 return needs_barrier_impl(phase, orig, n, rb_mem, allow_fromspace, visited);
79 }
80
81 bool ShenandoahBarrierNode::needs_barrier_impl(PhaseGVN* phase, ShenandoahBarrierNode* orig, Node* n, Node* rb_mem, bool allow_fromspace, Unique_Node_List &visited) {
82
83 if (visited.member(n)) {
84 return false; // Been there.
85 }
86 visited.push(n);
87
88 if (n->is_Allocate()) {
89 // tty->print_cr("killed barrier for newly allocated object");
90 return false;
91 }
92
93 if (n->is_CallJava() || n->Opcode() == Op_CallLeafNoFP) {
94 return true;
95 }
96
97 const Type* type = phase->type(n);
98 if (type == Type::TOP) {
99 return false;
100 }
101 if (type->make_ptr()->higher_equal(TypePtr::NULL_PTR)) {
102 // tty->print_cr("killed barrier for NULL object");
103 return false;
104 }
105 if (type->make_oopptr() && type->make_oopptr()->const_oop() != NULL) {
106 // tty->print_cr("killed barrier for constant object");
107 return ShenandoahBarriersForConst;
108 }
109
110 if (ShenandoahOptimizeStableFinals) {
111 const TypeAryPtr* ary = type->isa_aryptr();
112 if (ary && ary->is_stable() && allow_fromspace) {
113 return false;
114 }
115 }
116
117 if (n->is_CheckCastPP() || n->is_ConstraintCast()) {
118 return needs_barrier_impl(phase, orig, n->in(1), rb_mem, allow_fromspace, visited);
119 }
120 if (n->is_Parm()) {
121 return true;
122 }
123 if (n->is_Proj()) {
124 return needs_barrier_impl(phase, orig, n->in(0), rb_mem, allow_fromspace, visited);
125 }
126 if (n->is_Phi()) {
127 bool need_barrier = false;
128 for (uint i = 1; i < n->req() && ! need_barrier; i++) {
129 Node* input = n->in(i);
130 if (input == NULL) {
131 need_barrier = true; // Phi not complete yet?
132 } else if (needs_barrier_impl(phase, orig, input, rb_mem, allow_fromspace, visited)) {
133 need_barrier = true;
134 }
135 }
136 return need_barrier;
137 }
138 if (n->is_CMove()) {
139 return needs_barrier_impl(phase, orig, n->in(CMoveNode::IfFalse), rb_mem, allow_fromspace, visited) ||
140 needs_barrier_impl(phase, orig, n->in(CMoveNode::IfTrue ), rb_mem, allow_fromspace, visited);
141 }
142 if (n->Opcode() == Op_CreateEx) {
143 return true;
144 }
145 if (n->Opcode() == Op_ShenandoahWriteBarrier) {
146 // tty->print_cr("skipped barrier for chained write barrier object");
147 return false;
148 }
149 if (n->Opcode() == Op_ShenandoahReadBarrier) {
150 if (rb_mem == n->in(Memory)) {
151 // tty->print_cr("Eliminated chained read barrier");
152 return false;
153 } else {
154 return true;
155 }
156 }
157
158 if (n->Opcode() == Op_LoadP ||
159 n->Opcode() == Op_LoadN ||
160 n->Opcode() == Op_GetAndSetP ||
161 n->Opcode() == Op_CompareAndExchangeP ||
162 n->Opcode() == Op_GetAndSetN ||
163 n->Opcode() == Op_CompareAndExchangeN) {
164 return true;
165 }
166 if (n->Opcode() == Op_DecodeN ||
167 n->Opcode() == Op_EncodeP) {
168 return needs_barrier_impl(phase, orig, n->in(1), rb_mem, allow_fromspace, visited);
169 }
170
171 #ifdef ASSERT
172 tty->print("need barrier on?: "); n->dump();
173 ShouldNotReachHere();
174 #endif
175 return true;
176 }
177
178 /**
179 * In Shenandoah, we need barriers on acmp (and similar instructions that compare two
180 * oops) to avoid false negatives. If it compares a from-space and a to-space
181 * copy of an object, a regular acmp would return false, even though both are
182 * the same. The acmp barrier compares the two objects, and when they are
183 * *not equal* it does a read-barrier on both, and compares them again. When it
184 * failed because of different copies of the object, we know that the object
185 * must already have been evacuated (and therefore doesn't require a write-barrier).
186 */
187 void ShenandoahBarrierNode::do_cmpp_if(GraphKit& kit, Node*& taken_branch, Node*& untaken_branch, Node*& taken_memory, Node*& untaken_memory) {
188 assert(taken_memory == NULL && untaken_memory == NULL, "unexpected memory inputs");
189 if (!UseShenandoahGC || !ShenandoahAcmpBarrier || ShenandoahVerifyOptoBarriers) {
190 return;
191 }
192 if (taken_branch->is_top() || untaken_branch->is_top()) {
193 // one of the branches is known to be untaken
194 return;
195 }
196 assert(taken_branch->is_IfProj() && untaken_branch->is_IfProj(), "if projections only");
197 assert(taken_branch->in(0) == untaken_branch->in(0), "should come from same if");
198 IfNode* iff = taken_branch->in(0)->as_If();
199 BoolNode* bol = iff->in(1)->as_Bool();
200 Node* cmp = bol->in(1);
201 if (cmp->Opcode() != Op_CmpP) {
202 return;
203 }
204 Node* a = cmp->in(1);
205 Node* b = cmp->in(2);
206 const Type* a_type = kit.gvn().type(a);
207 const Type* b_type = kit.gvn().type(b);
208 if (a_type->higher_equal(TypePtr::NULL_PTR) || b_type->higher_equal(TypePtr::NULL_PTR)) {
209 // We know one arg is gonna be null. No need for barriers.
210 return;
211 }
212
213 const TypePtr* a_adr_type = ShenandoahBarrierNode::brooks_pointer_type(a_type);
214 const TypePtr* b_adr_type = ShenandoahBarrierNode::brooks_pointer_type(b_type);
215 if ((! ShenandoahBarrierNode::needs_barrier(&kit.gvn(), NULL, a, kit.memory(a_adr_type), false)) &&
216 (! ShenandoahBarrierNode::needs_barrier(&kit.gvn(), NULL, b, kit.memory(b_adr_type), false))) {
217 // We know both args are in to-space already. No acmp barrier needed.
218 return;
219 }
220
221 Node* equal_path = iff->proj_out(true);
222 Node* not_equal_path = iff->proj_out(false);
223
224 if (bol->_test._test == BoolTest::ne) {
225 swap(equal_path, not_equal_path);
226 }
227
228 Node* init_equal_path = equal_path;
229 Node* init_not_equal_path = not_equal_path;
230
231 uint alias_a = kit.C->get_alias_index(a_adr_type);
232 uint alias_b = kit.C->get_alias_index(b_adr_type);
233
234 Node* equal_memory = NULL;
235 Node* not_equal_memory = NULL;
236
237 RegionNode* region = new RegionNode(3);
238 region->init_req(1, equal_path);
239 PhiNode* mem_phi = NULL;
240 if (alias_a == alias_b) {
241 mem_phi = PhiNode::make(region, kit.memory(alias_a), Type::MEMORY, kit.C->get_adr_type(alias_a));
242 } else {
243 Node* mem = kit.reset_memory();
244 mem_phi = PhiNode::make(region, mem, Type::MEMORY, TypePtr::BOTTOM);
245 kit.set_all_memory(mem);
246 }
247
248 kit.set_control(not_equal_path);
249
250 Node* mb = NULL;
251 if (alias_a == alias_b) {
252 Node* mem = kit.reset_memory();
253 mb = MemBarNode::make(kit.C, Op_MemBarAcquire, alias_a);
254 mb->init_req(TypeFunc::Control, kit.control());
255 mb->init_req(TypeFunc::Memory, mem);
256 Node* membar = kit.gvn().transform(mb);
257 kit.set_control(kit.gvn().transform(new ProjNode(membar, TypeFunc::Control)));
258 Node* newmem = kit.gvn().transform(new ProjNode(membar, TypeFunc::Memory));
259 kit.set_all_memory(mem);
260 kit.set_memory(newmem, alias_a);
261 } else {
262 mb = kit.insert_mem_bar(Op_MemBarAcquire);
263 }
264
265 a = kit.shenandoah_read_barrier_acmp(a);
266 b = kit.shenandoah_read_barrier_acmp(b);
267
268 Node* cmp2 = kit.gvn().transform(new CmpPNode(a, b));
269 Node* bol2 = bol->clone();
270 bol2->set_req(1, cmp2);
271 bol2 = kit.gvn().transform(bol2);
272 Node* iff2 = iff->clone();
273 iff2->set_req(0, kit.control());
274 iff2->set_req(1, bol2);
275 kit.gvn().set_type(iff2, kit.gvn().type(iff));
276 Node* equal_path2 = equal_path->clone();
277 equal_path2->set_req(0, iff2);
278 equal_path2 = kit.gvn().transform(equal_path2);
279 Node* not_equal_path2 = not_equal_path->clone();
280 not_equal_path2->set_req(0, iff2);
281 not_equal_path2 = kit.gvn().transform(not_equal_path2);
282
283 region->init_req(2, equal_path2);
284 not_equal_memory = kit.reset_memory();
285 not_equal_path = not_equal_path2;
286
287 kit.set_all_memory(not_equal_memory);
288
289 if (alias_a == alias_b) {
290 mem_phi->init_req(2, kit.memory(alias_a));
291 kit.set_memory(mem_phi, alias_a);
292 } else {
293 mem_phi->init_req(2, kit.reset_memory());
294 }
295
296 kit.record_for_igvn(mem_phi);
297 kit.gvn().set_type(mem_phi, Type::MEMORY);
298
299 if (alias_a == alias_b) {
300 equal_memory = kit.reset_memory();
301 } else {
302 equal_memory = mem_phi;
303 }
304
305 assert(kit.map()->memory() == NULL, "no live memory state");
306 equal_path = kit.gvn().transform(region);
307
308 if (taken_branch == init_equal_path) {
309 assert(untaken_branch == init_not_equal_path, "inconsistent");
310 taken_branch = equal_path;
311 untaken_branch = not_equal_path;
312 taken_memory = equal_memory;
313 untaken_memory = not_equal_memory;
314 } else {
315 assert(taken_branch == init_not_equal_path, "inconsistent");
316 assert(untaken_branch == init_equal_path, "inconsistent");
317 taken_branch = not_equal_path;
318 untaken_branch = equal_path;
319 taken_memory = not_equal_memory;
320 untaken_memory = equal_memory;
321 }
322 }
323
324 bool ShenandoahReadBarrierNode::dominates_memory_rb_impl(PhaseGVN* phase,
325 Node* b1,
326 Node* b2,
327 Node* current,
328 bool linear) {
329 ResourceMark rm;
330 VectorSet visited(Thread::current()->resource_area());
331 Node_Stack phis(0);
332
333 for(int i = 0; i < 10; i++) {
334 if (current == NULL) {
335 return false;
336 } else if (visited.test_set(current->_idx) || current->is_top() || current == b1) {
337 current = NULL;
338 while (phis.is_nonempty() && current == NULL) {
339 uint idx = phis.index();
340 Node* phi = phis.node();
341 if (idx >= phi->req()) {
342 phis.pop();
343 } else {
344 current = phi->in(idx);
345 phis.set_index(idx+1);
346 }
347 }
348 if (current == NULL) {
349 return true;
350 }
351 } else if (current == phase->C->immutable_memory()) {
352 return false;
353 } else if (current->isa_Phi()) {
354 if (!linear) {
355 return false;
356 }
357 phis.push(current, 2);
358 current = current->in(1);
359 } else if (current->Opcode() == Op_ShenandoahWriteBarrier) {
360 const Type* in_type = current->bottom_type();
361 const Type* this_type = b2->bottom_type();
362 if (is_independent(in_type, this_type)) {
363 current = current->in(Memory);
364 } else {
365 return false;
366 }
367 } else if (current->Opcode() == Op_ShenandoahWBMemProj) {
368 current = current->in(0);
369 } else if (current->is_Proj()) {
370 current = current->in(0);
371 } else if (current->is_Call()) {
372 return false; // TODO: Maybe improve by looking at the call's memory effects?
373 } else if (current->is_MemBar()) {
374 return false; // TODO: Do we need to stop at *any* membar?
375 } else if (current->is_MergeMem()) {
376 // if (true) return false;
377 // tty->print_cr("current == mergemem: "); current->dump();
378 const TypePtr* adr_type = brooks_pointer_type(phase->type(b2));
379 uint alias_idx = phase->C->get_alias_index(adr_type);
380 current = current->as_MergeMem()->memory_at(alias_idx);
381 } else {
382 // tty->print_cr("what else can we see here:");
383 #ifdef ASSERT
384 current->dump();
385 #endif
386 ShouldNotReachHere();
387 return false;
388 }
389 }
390 return false;
391 }
392
393 bool ShenandoahReadBarrierNode::is_independent(Node* mem) {
394 if (mem->is_Phi() || mem->is_Proj() || mem->is_MergeMem()) {
395 return true;
396 } else if (mem->Opcode() == Op_ShenandoahWriteBarrier) {
397 const Type* mem_type = mem->bottom_type();
398 const Type* this_type = bottom_type();
399 if (is_independent(mem_type, this_type)) {
400 return true;
401 } else {
402 return false;
403 }
404 } else if (mem->is_Call() || mem->is_MemBar()) {
405 return false;
406 }
407 #ifdef ASSERT
408 mem->dump();
409 #endif
410 ShouldNotReachHere();
411 return true;
412 }
413
414
415 bool ShenandoahReadBarrierNode::dominates_memory_rb(PhaseGVN* phase, Node* b1, Node* b2, bool linear) {
416 return dominates_memory_rb_impl(phase, b1->in(Memory), b2, b2->in(Memory), linear);
417 }
418
419 bool ShenandoahReadBarrierNode::is_independent(const Type* in_type, const Type* this_type) {
420 assert(in_type->isa_oopptr(), "expect oop ptr");
421 assert(this_type->isa_oopptr(), "expect oop ptr");
422 /*
423 if ((! in_type->isa_oopptr()) || (! this_type->isa_oopptr())) {
424 #ifdef ASSERT
425 tty->print_cr("not oopptr");
426 tty->print("in: "); in_type->dump(); tty->print_cr(" ");
427 tty->print("this: "); this_type->dump(); tty->print_cr(" ");
428 #endif
429 return false;
430 }
431 */
432
433 ciKlass* in_kls = in_type->is_oopptr()->klass();
434 ciKlass* this_kls = this_type->is_oopptr()->klass();
435 if (in_kls != NULL && this_kls != NULL &&
436 in_kls->is_loaded() && this_kls->is_loaded() &&
437 (!in_kls->is_subclass_of(this_kls)) &&
438 (!this_kls->is_subclass_of(in_kls))) {
439 #ifdef ASSERT
440 // tty->print_cr("independent: ");
441 // tty->print("in: "); in_kls->print(); tty->print_cr(" ");
442 // tty->print("this: "); this_kls->print(); tty->print_cr(" ");
443 #endif
444 return true;
445 }
446 #ifdef ASSERT
447 // tty->print_cr("possibly dependend?");
448 // tty->print("in: "); in_type->dump(); tty->print_cr(" ");
449 // tty->print("this: "); this_type->dump(); tty->print_cr(" ");
450 #endif
451 return false;
452 }
453
454 Node* ShenandoahReadBarrierNode::Ideal(PhaseGVN *phase, bool can_reshape) {
455
456 if (! can_reshape) {
457 return NULL;
458 }
459
460 if (in(Memory) == phase->C->immutable_memory()) return NULL;
461
462 // If memory input is a MergeMem, take the appropriate slice out of it.
463 Node* mem_in = in(Memory);
464 if (mem_in->isa_MergeMem()) {
465 const TypePtr* adr_type = brooks_pointer_type(bottom_type());
466 uint alias_idx = phase->C->get_alias_index(adr_type);
467 mem_in = mem_in->as_MergeMem()->memory_at(alias_idx);
468 set_req(Memory, mem_in);
469 return this;
470 }
471
472 Node* input = in(Memory);
473 if (input->Opcode() == Op_ShenandoahWBMemProj) {
474 Node* wb = input->in(0);
475 const Type* in_type = phase->type(wb);
476 // is_top() test not sufficient here: we can come here after CCP
477 // in a dead branch of the graph that has not yet been removed.
478 if (in_type == Type::TOP) return NULL; // Dead path.
479 assert(wb->Opcode() == Op_ShenandoahWriteBarrier, "expect write barrier");
480 if (is_independent(in_type, _type)) {
481 phase->igvn_rehash_node_delayed(wb);
482 set_req(Memory, wb->in(Memory));
483 if (can_reshape && input->outcnt() == 0) {
484 phase->is_IterGVN()->_worklist.push(input);
485 }
486 return this;
487 }
488 }
489 return NULL;
490 }
491
492 Node* ShenandoahWriteBarrierNode::Identity(PhaseGVN* phase) {
493 assert(in(0) != NULL, "should have control");
494 PhaseIterGVN* igvn = phase->is_IterGVN();
495 Node* mem_in = in(Memory);
496 Node* mem_proj = NULL;
497
498 if (igvn != NULL) {
499 mem_proj = find_out_with(Op_ShenandoahWBMemProj);
500 if (mem_proj == NULL || mem_in == mem_proj) {
501 return this;
502 }
503 }
504
505 Node* replacement = Identity_impl(phase);
506 if (igvn != NULL) {
507 if (replacement != NULL && replacement != this) {
508 igvn->replace_node(mem_proj, mem_in);
509 }
510 }
511 return replacement;
512 }
513
514
515 Node* ShenandoahWriteBarrierNode::Ideal(PhaseGVN *phase, bool can_reshape) {
516 assert(in(0) != NULL, "should have control");
517 if (!can_reshape) {
518 return NULL;
519 }
520
521 PhaseIterGVN* igvn = phase->is_IterGVN();
522 Node* mem_proj = find_out_with(Op_ShenandoahWBMemProj);
523 Node* mem_in = in(Memory);
524
525 if (mem_in == phase->C->immutable_memory()) return NULL;
526
527 if (mem_in->isa_MergeMem()) {
528 const TypePtr* adr_type = brooks_pointer_type(bottom_type());
529 uint alias_idx = phase->C->get_alias_index(adr_type);
530 mem_in = mem_in->as_MergeMem()->memory_at(alias_idx);
531 set_req(Memory, mem_in);
532 return this;
533 }
534
535 return NULL;
536 }
537
538 bool ShenandoahWriteBarrierNode::expand(Compile* C, PhaseIterGVN& igvn, int& loop_opts_cnt) {
539 if (UseShenandoahGC && ShenandoahWriteBarrierToIR) {
540 if (C->shenandoah_barriers_count() > 0) {
541 bool attempt_more_loopopts = ShenandoahLoopOptsAfterExpansion && (C->shenandoah_barriers_count() > 1 || C->has_loops());
542 C->clear_major_progress();
543 PhaseIdealLoop ideal_loop(igvn, LoopOptsShenandoahExpand);
544 if (C->failing()) return false;
545 PhaseIdealLoop::verify(igvn);
546 DEBUG_ONLY(ShenandoahBarrierNode::verify_raw_mem(C->root());)
547 if (attempt_more_loopopts) {
548 C->set_major_progress();
549 if (!C->optimize_loops(loop_opts_cnt, igvn, LoopOptsShenandoahPostExpand)) {
550 return false;
551 }
552 C->clear_major_progress();
553 }
554 }
555 }
556 return true;
557 }
558
559 bool ShenandoahWriteBarrierNode::is_evacuation_in_progress_test(Node* iff) {
560 assert(iff->is_If(), "bad input");
561 if (iff->Opcode() != Op_If) {
562 return false;
563 }
564 Node* bol = iff->in(1);
565 if (!bol->is_Bool() || bol->as_Bool()->_test._test != BoolTest::ne) {
566 return false;
567 }
568 Node* cmp = bol->in(1);
569 if (cmp->Opcode() != Op_CmpI) {
570 return false;
571 }
572 Node* in1 = cmp->in(1);
573 Node* in2 = cmp->in(2);
574 if (in2->find_int_con(-1) != 0) {
575 return false;
576 }
577 if (in1->Opcode() != Op_AndI) {
578 return false;
579 }
580 in2 = in1->in(2);
581 if (in2->find_int_con(-1) != ShenandoahHeap::EVACUATION) {
582 return false;
583 }
584 in1 = in1->in(1);
585
586 return is_gc_state_load(in1);
587 }
588
589 bool ShenandoahWriteBarrierNode::is_gc_state_load(Node *n) {
590 if (n->Opcode() != Op_LoadUB && n->Opcode() != Op_LoadB) {
591 return false;
592 }
593 Node* addp = n->in(MemNode::Address);
594 if (!addp->is_AddP()) {
595 return false;
596 }
597 Node* base = addp->in(AddPNode::Address);
598 Node* off = addp->in(AddPNode::Offset);
599 if (base->Opcode() != Op_ThreadLocal) {
600 return false;
601 }
602 if (off->find_intptr_t_con(-1) != in_bytes(JavaThread::gc_state_offset())) {
603 return false;
604 }
605 return true;
606 }
607
608 bool ShenandoahWriteBarrierNode::try_common_gc_state_load(Node *n, PhaseIdealLoop *phase) {
609 assert(is_gc_state_load(n), "inconsistent");
610 Node* addp = n->in(MemNode::Address);
611 Node* dominator = NULL;
612 for (DUIterator_Fast imax, i = addp->fast_outs(imax); i < imax; i++) {
613 Node* u = addp->fast_out(i);
614 if (u != n && phase->is_dominator(u->in(0), n->in(0))) {
615 if (dominator == NULL) {
616 dominator = u;
617 } else {
618 if (phase->dom_depth(u->in(0)) < phase->dom_depth(dominator->in(0))) {
619 dominator = u;
620 }
621 }
622 }
623 }
624 if (dominator == NULL) {
625 return false;
626 }
627 ResourceMark rm;
628 Unique_Node_List wq;
629 wq.push(n->in(0));
630 for (uint next = 0; next < wq.size(); next++) {
631 Node *m = wq.at(next);
632 if (m->is_SafePoint() && !m->is_CallLeaf()) {
633 return false;
634 }
635 if (m->is_Region()) {
636 for (uint i = 1; i < m->req(); i++) {
637 wq.push(m->in(i));
638 }
639 } else {
640 wq.push(m->in(0));
641 }
642 }
643 phase->igvn().replace_node(n, dominator);
644
645 return true;
646 }
647
648 Node* ShenandoahWriteBarrierNode::evacuation_in_progress_test_ctrl(Node* iff) {
649 assert(is_evacuation_in_progress_test(iff), "bad input");
650 Node* c = iff;
651 if (ShenandoahWriteBarrierMemBar) {
652 do {
653 assert(c->in(0)->is_Proj() && c->in(0)->in(0)->is_MemBar(), "where's the mem bar?");
654 c = c->in(0)->in(0);
655 } while (c->adr_type() != TypeRawPtr::BOTTOM);
656 }
657 return c->in(0);
658 }
659
660 bool ShenandoahBarrierNode::dominates_memory_impl(PhaseGVN* phase,
661 Node* b1,
662 Node* b2,
663 Node* current,
664 bool linear) {
665 ResourceMark rm;
666 VectorSet visited(Thread::current()->resource_area());
667 Node_Stack phis(0);
668
669
670 for(int i = 0; i < 10; i++) {
671 if (current == NULL) {
672 return false;
673 } else if (visited.test_set(current->_idx) || current->is_top() || current == b1) {
674 current = NULL;
675 while (phis.is_nonempty() && current == NULL) {
676 uint idx = phis.index();
677 Node* phi = phis.node();
678 if (idx >= phi->req()) {
679 phis.pop();
680 } else {
681 current = phi->in(idx);
682 phis.set_index(idx+1);
683 }
684 }
685 if (current == NULL) {
686 return true;
687 }
688 } else if (current == b2) {
689 return false;
690 } else if (current == phase->C->immutable_memory()) {
691 return false;
692 } else if (current->isa_Phi()) {
693 if (!linear) {
694 return false;
695 }
696 phis.push(current, 2);
697 current = current->in(1);
698 } else if (current->Opcode() == Op_ShenandoahWriteBarrier) {
699 current = current->in(Memory);
700 } else if (current->Opcode() == Op_ShenandoahWBMemProj) {
701 current = current->in(0);
702 } else if (current->is_Proj()) {
703 current = current->in(0);
704 } else if (current->is_Call()) {
705 current = current->in(TypeFunc::Memory);
706 } else if (current->is_MemBar()) {
707 current = current->in(TypeFunc::Memory);
708 } else if (current->is_MergeMem()) {
709 const TypePtr* adr_type = brooks_pointer_type(phase->type(b2));
710 uint alias_idx = phase->C->get_alias_index(adr_type);
711 current = current->as_MergeMem()->memory_at(alias_idx);
712 } else {
713 #ifdef ASSERT
714 current->dump();
715 #endif
716 ShouldNotReachHere();
717 return false;
718 }
719 }
720 return false;
721 }
722
723 /**
724 * Determines if b1 dominates b2 through memory inputs. It returns true if:
725 * - b1 can be reached by following each branch in b2's memory input (through phis, etc)
726 * - or we get back to b2 (i.e. through a loop) without seeing b1
727 * In all other cases, (in particular, if we reach immutable_memory without having seen b1)
728 * we return false.
729 */
730 bool ShenandoahBarrierNode::dominates_memory(PhaseGVN* phase, Node* b1, Node* b2, bool linear) {
731 return dominates_memory_impl(phase, b1, b2, b2->in(Memory), linear);
732 }
733
734 Node* ShenandoahBarrierNode::Identity_impl(PhaseGVN* phase) {
735 Node* n = in(ValueIn);
736
737 Node* rb_mem = Opcode() == Op_ShenandoahReadBarrier ? in(Memory) : NULL;
738 if (! needs_barrier(phase, this, n, rb_mem, _allow_fromspace)) {
739 return n;
740 }
741
742 // tty->print_cr("find sibling for: "); dump(2);
743 // Try to find a write barrier sibling with identical inputs that we can fold into.
744 for (DUIterator i = n->outs(); n->has_out(i); i++) {
745 Node* sibling = n->out(i);
746 if (sibling == this) {
747 continue;
748 }
749 /*
750 assert(sibling->Opcode() != Op_ShenandoahWriteBarrier ||
751 Opcode() != Op_ShenandoahWriteBarrier || hash() == sibling->hash(),
752 "if this is a write barrier, then sibling can't be write barrier too");
753 */
754 if (sibling->Opcode() != Op_ShenandoahWriteBarrier) {
755 continue;
756 }
757 /*
758 if (sibling->outcnt() == 0) {
759 // Some dead node.
760 continue;
761 }
762 */
763 assert(sibling->in(ValueIn) == in(ValueIn), "sanity");
764 assert(sibling->Opcode() == Op_ShenandoahWriteBarrier, "sanity");
765 // tty->print_cr("candidate: "); sibling->dump();
766
767 if (dominates_memory(phase, sibling, this, phase->is_IterGVN() == NULL)) {
768
769 /*
770 tty->print_cr("matched barrier:");
771 sibling->dump();
772 tty->print_cr("for: ");
773 dump();
774 */
775 return sibling;
776 }
777
778 /*
779 tty->print_cr("couldn't match candidate:");
780 sibling->dump(2);
781 */
782 }
783 /*
784 tty->print_cr("couldn't match barrier to any:");
785 dump();
786 */
787 return this;
788 }
789
790 #ifndef PRODUCT
791 void ShenandoahBarrierNode::dump_spec(outputStream *st) const {
792 const TypePtr* adr = adr_type();
793 if (adr == NULL) {
794 return;
795 }
796 st->print(" @");
797 adr->dump_on(st);
798 st->print(" (");
799 Compile::current()->alias_type(adr)->adr_type()->dump_on(st);
800 st->print(") ");
801 }
802 #endif
803
804 Node* ShenandoahReadBarrierNode::Identity(PhaseGVN* phase) {
805
806 // if (true) return this;
807
808 // tty->print("optimizing rb: "); dump();
809 Node* id = Identity_impl(phase);
810
811 if (id == this && phase->is_IterGVN()) {
812 Node* n = in(ValueIn);
813 // No success in super call. Try to combine identical read barriers.
814 for (DUIterator i = n->outs(); n->has_out(i); i++) {
815 Node* sibling = n->out(i);
816 if (sibling == this || sibling->Opcode() != Op_ShenandoahReadBarrier) {
817 continue;
818 }
819 assert(sibling->in(ValueIn) == in(ValueIn), "sanity");
820 if (phase->is_IterGVN()->hash_find(sibling) &&
821 sibling->bottom_type() == bottom_type() &&
822 sibling->in(Control) == in(Control) &&
823 dominates_memory_rb(phase, sibling, this, phase->is_IterGVN() == NULL)) {
824 /*
825 if (in(Memory) != sibling->in(Memory)) {
826 tty->print_cr("interesting rb-fold");
827 dump();
828 sibling->dump();
829 }
830 */
831 return sibling;
832 }
833 }
834 }
835 return id;
836 }
837
838 const Type* ShenandoahBarrierNode::Value(PhaseGVN* phase) const {
839 // Either input is TOP ==> the result is TOP
840 const Type *t1 = phase->type(in(Memory));
841 if (t1 == Type::TOP) return Type::TOP;
842 const Type *t2 = phase->type(in(ValueIn));
843 if( t2 == Type::TOP ) return Type::TOP;
844
845 Node* input = in(ValueIn);
846 const Type* type = phase->type(input)->is_oopptr()->cast_to_nonconst();
847 return type;
848 }
849
850 uint ShenandoahBarrierNode::hash() const {
851 return TypeNode::hash() + _allow_fromspace;
852 }
853
854 uint ShenandoahBarrierNode::cmp(const Node& n) const {
855 return _allow_fromspace == ((ShenandoahBarrierNode&) n)._allow_fromspace
856 && TypeNode::cmp(n);
857 }
858
859 uint ShenandoahBarrierNode::size_of() const {
860 return sizeof(*this);
861 }
862
863 Node* ShenandoahWBMemProjNode::Identity(PhaseGVN* phase) {
864
865 Node* wb = in(0);
866 if (wb->is_top()) return phase->C->top(); // Dead path.
867
868 assert(wb->Opcode() == Op_ShenandoahWriteBarrier, "expect write barrier");
869 PhaseIterGVN* igvn = phase->is_IterGVN();
870 // We can't do the below unless the graph is fully constructed.
871 if (igvn == NULL) {
872 return this;
873 }
874
875 // If the mem projection has no barrier users, it's not needed anymore.
876 Unique_Node_List visited;
877 if (wb->outcnt() == 1) {
878 return wb->in(ShenandoahBarrierNode::Memory);
879 }
880
881 return this;
882 }
883
884 #ifdef ASSERT
885 bool ShenandoahBarrierNode::verify_helper(Node* in, Node_Stack& phis, VectorSet& visited, verify_type t, bool trace, Unique_Node_List& barriers_used) {
886 assert(phis.size() == 0, "");
887
888 while (true) {
889 if (!in->bottom_type()->make_ptr()->make_oopptr()) {
890 if (trace) {tty->print_cr("Non oop");}
891 } else if (t == ShenandoahLoad && ShenandoahOptimizeStableFinals &&
892 in->bottom_type()->make_ptr()->isa_aryptr() &&
893 in->bottom_type()->make_ptr()->is_aryptr()->is_stable()) {
894 if (trace) {tty->print_cr("Stable array load");}
895 } else {
896 if (in->is_ConstraintCast()) {
897 in = in->in(1);
898 continue;
899 } else if (in->is_AddP()) {
900 assert(!in->in(AddPNode::Address)->is_top(), "no raw memory access");
901 in = in->in(AddPNode::Address);
902 continue;
903 } else if (in->is_Con() && !ShenandoahBarriersForConst) {
904 if (trace) {tty->print("Found constant"); in->dump();}
905 } else if (in->is_ShenandoahBarrier()) {
906 if (t == ShenandoahStore && in->Opcode() != Op_ShenandoahWriteBarrier) {
907 return false;
908 }
909 barriers_used.push(in);
910 if (trace) {tty->print("Found barrier"); in->dump();}
911 } else if (in->is_Proj() && in->in(0)->is_Allocate()) {
912 if (trace) {tty->print("Found alloc"); in->in(0)->dump();}
913 } else if (in->is_Phi()) {
914 if (!visited.test_set(in->_idx)) {
915 if (trace) {tty->print("Pushed phi:"); in->dump();}
916 phis.push(in, 2);
917 in = in->in(1);
918 continue;
919 }
920 if (trace) {tty->print("Already seen phi:"); in->dump();}
921 } else if (in->Opcode() == Op_CMoveP || in->Opcode() == Op_CMoveN) {
922 if (!visited.test_set(in->_idx)) {
923 if (trace) {tty->print("Pushed cmovep:"); in->dump();}
924 phis.push(in, CMoveNode::IfTrue);
925 in = in->in(CMoveNode::IfFalse);
926 continue;
927 }
928 if (trace) {tty->print("Already seen cmovep:"); in->dump();}
929 } else if (in->Opcode() == Op_EncodeP || in->Opcode() == Op_DecodeN) {
930 in = in->in(1);
931 continue;
932 } else {
933 return false;
934 }
935 }
936 bool cont = false;
937 while (phis.is_nonempty()) {
938 uint idx = phis.index();
939 Node* phi = phis.node();
940 if (idx >= phi->req()) {
941 if (trace) {tty->print("Popped phi:"); phi->dump();}
942 phis.pop();
943 continue;
944 }
945 if (trace) {tty->print("Next entry(%d) for phi:", idx); phi->dump();}
946 in = phi->in(idx);
947 phis.set_index(idx+1);
948 cont = true;
949 break;
950 }
951 if (!cont) {
952 break;
953 }
954 }
955 return true;
956 }
957
958 void ShenandoahBarrierNode::report_verify_failure(const char *msg, Node *n1, Node *n2) {
959 if (n1 != NULL) {
960 n1->dump(+10);
961 }
962 if (n2 != NULL) {
963 n2->dump(+10);
964 }
965 fatal("%s", msg);
966 }
967
968 void ShenandoahBarrierNode::verify(RootNode* root) {
969 ResourceMark rm;
970 Unique_Node_List wq;
971 GrowableArray<Node*> barriers;
972 Unique_Node_List barriers_used;
973 Node_Stack phis(0);
974 VectorSet visited(Thread::current()->resource_area());
975 const bool trace = false;
976 const bool verify_no_useless_barrier = false;
977
978 wq.push(root);
979 for (uint next = 0; next < wq.size(); next++) {
980 Node *n = wq.at(next);
981 if (n->is_Load()) {
982 const bool trace = false;
983 if (trace) {tty->print("Verifying"); n->dump();}
984 if (n->Opcode() == Op_LoadRange || n->Opcode() == Op_LoadKlass || n->Opcode() == Op_LoadNKlass) {
985 if (trace) {tty->print_cr("Load range/klass");}
986 } else {
987 const TypePtr* adr_type = n->as_Load()->adr_type();
988
989 if (adr_type->isa_oopptr() && adr_type->is_oopptr()->offset() == oopDesc::mark_offset_in_bytes()) {
990 if (trace) {tty->print_cr("Mark load");}
991 } else if (adr_type->isa_instptr() &&
992 adr_type->is_instptr()->klass()->is_subtype_of(Compile::current()->env()->Reference_klass()) &&
993 adr_type->is_instptr()->offset() == java_lang_ref_Reference::referent_offset) {
994 if (trace) {tty->print_cr("Reference.get()");}
995 } else {
996 bool verify = true;
997 if (adr_type->isa_instptr()) {
998 const TypeInstPtr* tinst = adr_type->is_instptr();
999 ciKlass* k = tinst->klass();
1000 assert(k->is_instance_klass(), "");
1001 ciInstanceKlass* ik = (ciInstanceKlass*)k;
1002 int offset = adr_type->offset();
1003
1004 if ((ik->debug_final_field_at(offset) && ShenandoahOptimizeInstanceFinals) ||
1005 (ik->debug_stable_field_at(offset) && ShenandoahOptimizeStableFinals)) {
1006 if (trace) {tty->print_cr("Final/stable");}
1007 verify = false;
1008 } else if (k == ciEnv::current()->Class_klass() &&
1009 tinst->const_oop() != NULL &&
1010 tinst->offset() >= (ik->size_helper() * wordSize)) {
1011 ciInstanceKlass* k = tinst->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
1012 ciField* field = k->get_field_by_offset(tinst->offset(), true);
1013 if ((ShenandoahOptimizeStaticFinals && field->is_final()) ||
1014 (ShenandoahOptimizeStableFinals && field->is_stable())) {
1015 verify = false;
1016 }
1017 }
1018 }
1019
1020 if (verify && !ShenandoahBarrierNode::verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahLoad, trace, barriers_used)) {
1021 report_verify_failure("Shenandoah verification: Load should have barriers", n);
1022 }
1023 }
1024 }
1025 } else if (n->is_Store()) {
1026 const bool trace = false;
1027
1028 if (trace) {tty->print("Verifying"); n->dump();}
1029 if (n->in(MemNode::ValueIn)->bottom_type()->make_oopptr()) {
1030 Node* adr = n->in(MemNode::Address);
1031 bool verify = true;
1032
1033 if (adr->is_AddP() && adr->in(AddPNode::Base)->is_top()) {
1034 adr = adr->in(AddPNode::Address);
1035 if (adr->is_AddP()) {
1036 assert(adr->in(AddPNode::Base)->is_top(), "");
1037 adr = adr->in(AddPNode::Address);
1038 if (adr->Opcode() == Op_LoadP &&
1039 adr->in(MemNode::Address)->in(AddPNode::Base)->is_top() &&
1040 adr->in(MemNode::Address)->in(AddPNode::Address)->Opcode() == Op_ThreadLocal &&
1041 adr->in(MemNode::Address)->in(AddPNode::Offset)->find_intptr_t_con(-1) == in_bytes(JavaThread::satb_mark_queue_offset() +
1042 SATBMarkQueue::byte_offset_of_buf())) {
1043 if (trace) {tty->print_cr("G1 prebarrier");}
1044 verify = false;
1045 }
1046 }
1047 }
1048
1049 if (verify && !ShenandoahBarrierNode::verify_helper(n->in(MemNode::ValueIn), phis, visited, ShenandoahValue, trace, barriers_used)) {
1050 report_verify_failure("Shenandoah verification: Store should have barriers", n);
1051 }
1052 }
1053 if (!ShenandoahBarrierNode::verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahStore, trace, barriers_used)) {
1054 report_verify_failure("Shenandoah verification: Store (address) should have barriers", n);
1055 }
1056 } else if (n->Opcode() == Op_CmpP) {
1057 const bool trace = false;
1058
1059 Node* in1 = n->in(1);
1060 Node* in2 = n->in(2);
1061 if (in1->bottom_type()->isa_oopptr()) {
1062 if (trace) {tty->print("Verifying"); n->dump();}
1063
1064 bool mark_inputs = false;
1065 if (in1->bottom_type() == TypePtr::NULL_PTR || in2->bottom_type() == TypePtr::NULL_PTR ||
1066 ((in1->is_Con() || in2->is_Con()) && !ShenandoahBarriersForConst)) {
1067 if (trace) {tty->print_cr("Comparison against a constant");}
1068 mark_inputs = true;
1069 } else if ((in1->is_CheckCastPP() && in1->in(1)->is_Proj() && in1->in(1)->in(0)->is_Allocate()) ||
1070 (in2->is_CheckCastPP() && in2->in(1)->is_Proj() && in2->in(1)->in(0)->is_Allocate())) {
1071 if (trace) {tty->print_cr("Comparison with newly alloc'ed object");}
1072 mark_inputs = true;
1073 } else {
1074 assert(in2->bottom_type()->isa_oopptr(), "");
1075
1076 if (!ShenandoahBarrierNode::verify_helper(in1, phis, visited, ShenandoahStore, trace, barriers_used) ||
1077 !ShenandoahBarrierNode::verify_helper(in2, phis, visited, ShenandoahStore, trace, barriers_used)) {
1078 report_verify_failure("Shenandoah verification: Cmp should have barriers", n);
1079 }
1080 }
1081 if (verify_no_useless_barrier &&
1082 mark_inputs &&
1083 (!ShenandoahBarrierNode::verify_helper(in1, phis, visited, ShenandoahValue, trace, barriers_used) ||
1084 !ShenandoahBarrierNode::verify_helper(in2, phis, visited, ShenandoahValue, trace, barriers_used))) {
1085 phis.clear();
1086 visited.Reset();
1087 }
1088 }
1089 } else if (n->is_LoadStore()) {
1090 if (n->in(MemNode::ValueIn)->bottom_type()->isa_ptr() &&
1091 !ShenandoahBarrierNode::verify_helper(n->in(MemNode::ValueIn), phis, visited, ShenandoahLoad, trace, barriers_used)) {
1092 report_verify_failure("Shenandoah verification: LoadStore (value) should have barriers", n);
1093 }
1094
1095 if (n->in(MemNode::Address)->bottom_type()->isa_oopptr() && !ShenandoahBarrierNode::verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahStore, trace, barriers_used)) {
1096 report_verify_failure("Shenandoah verification: LoadStore (address) should have barriers", n);
1097 }
1098 } else if (n->Opcode() == Op_CallLeafNoFP || n->Opcode() == Op_CallLeaf) {
1099 CallNode* call = n->as_Call();
1100
1101 static struct {
1102 const char* name;
1103 struct {
1104 int pos;
1105 verify_type t;
1106 } args[6];
1107 } calls[] = {
1108 "aescrypt_encryptBlock",
1109 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
1110 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1111 "aescrypt_decryptBlock",
1112 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
1113 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1114 "multiplyToLen",
1115 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad }, { TypeFunc::Parms+4, ShenandoahStore },
1116 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1117 "squareToLen",
1118 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad }, { -1, ShenandoahNone},
1119 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1120 "montgomery_multiply",
1121 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad },
1122 { TypeFunc::Parms+6, ShenandoahStore }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1123 "montgomery_square",
1124 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+5, ShenandoahStore },
1125 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1126 "mulAdd",
1127 { { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone},
1128 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1129 "vectorizedMismatch",
1130 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone},
1131 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1132 "updateBytesCRC32",
1133 { { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
1134 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1135 "updateBytesAdler32",
1136 { { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
1137 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1138 "updateBytesCRC32C",
1139 { { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahLoad}, { -1, ShenandoahNone},
1140 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1141 "counterMode_AESCrypt",
1142 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
1143 { TypeFunc::Parms+3, ShenandoahStore }, { TypeFunc::Parms+5, ShenandoahStore }, { TypeFunc::Parms+6, ShenandoahStore } },
1144 "cipherBlockChaining_encryptAESCrypt",
1145 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
1146 { TypeFunc::Parms+3, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1147 "cipherBlockChaining_decryptAESCrypt",
1148 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
1149 { TypeFunc::Parms+3, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1150 "shenandoah_clone_barrier",
1151 { { TypeFunc::Parms, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
1152 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1153 "ghash_processBlocks",
1154 { { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad },
1155 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1156 "sha1_implCompress",
1157 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
1158 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1159 "sha256_implCompress",
1160 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
1161 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1162 "sha512_implCompress",
1163 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
1164 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1165 "sha1_implCompressMB",
1166 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
1167 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1168 "sha256_implCompressMB",
1169 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
1170 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1171 "sha512_implCompressMB",
1172 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
1173 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1174 };
1175
1176 if (call->is_call_to_arraycopystub()) {
1177 Node* dest = NULL;
1178 const TypeTuple* args = n->as_Call()->_tf->domain();
1179 for (uint i = TypeFunc::Parms, j = 0; i < args->cnt(); i++) {
1180 if (args->field_at(i)->isa_ptr()) {
1181 j++;
1182 if (j == 2) {
1183 dest = n->in(i);
1184 break;
1185 }
1186 }
1187 }
1188 if (!ShenandoahBarrierNode::verify_helper(n->in(TypeFunc::Parms), phis, visited, ShenandoahLoad, trace, barriers_used) ||
1189 !ShenandoahBarrierNode::verify_helper(dest, phis, visited, ShenandoahStore, trace, barriers_used)) {
1190 report_verify_failure("Shenandoah verification: ArrayCopy should have barriers", n);
1191 }
1192 } else if (strlen(call->_name) > 5 &&
1193 !strcmp(call->_name + strlen(call->_name) - 5, "_fill")) {
1194 if (!ShenandoahBarrierNode::verify_helper(n->in(TypeFunc::Parms), phis, visited, ShenandoahStore, trace, barriers_used)) {
1195 report_verify_failure("Shenandoah verification: _fill should have barriers", n);
1196 }
1197 } else if (!strcmp(call->_name, "g1_wb_pre")) {
1198 // skip
1199 } else {
1200 const int calls_len = sizeof(calls) / sizeof(calls[0]);
1201 int i = 0;
1202 for (; i < calls_len; i++) {
1203 if (!strcmp(calls[i].name, call->_name)) {
1204 break;
1205 }
1206 }
1207 if (i != calls_len) {
1208 const uint args_len = sizeof(calls[0].args) / sizeof(calls[0].args[0]);
1209 for (uint j = 0; j < args_len; j++) {
1210 int pos = calls[i].args[j].pos;
1211 if (pos == -1) {
1212 break;
1213 }
1214 if (!ShenandoahBarrierNode::verify_helper(call->in(pos), phis, visited, calls[i].args[j].t, trace, barriers_used)) {
1215 report_verify_failure("Shenandoah verification: intrinsic calls should have barriers", n);
1216 }
1217 }
1218 for (uint j = TypeFunc::Parms; j < call->req(); j++) {
1219 if (call->in(j)->bottom_type()->make_ptr() &&
1220 call->in(j)->bottom_type()->make_ptr()->isa_oopptr()) {
1221 uint k = 0;
1222 for (; k < args_len && calls[i].args[k].pos != (int)j; k++);
1223 if (k == args_len) {
1224 fatal("arg %d for call %s not covered", j, call->_name);
1225 }
1226 }
1227 }
1228 } else {
1229 for (uint j = TypeFunc::Parms; j < call->req(); j++) {
1230 if (call->in(j)->bottom_type()->make_ptr() &&
1231 call->in(j)->bottom_type()->make_ptr()->isa_oopptr()) {
1232 fatal("%s not covered", call->_name);
1233 }
1234 }
1235 }
1236 }
1237 } else if (n->is_ShenandoahBarrier()) {
1238 assert(!barriers.contains(n), "");
1239 assert(n->Opcode() != Op_ShenandoahWriteBarrier || n->find_out_with(Op_ShenandoahWBMemProj) != NULL, "bad shenandoah write barrier");
1240 assert(n->Opcode() != Op_ShenandoahWriteBarrier || n->outcnt() > 1, "bad shenandoah write barrier");
1241 barriers.push(n);
1242 } else if (n->is_AddP()
1243 || n->is_Phi()
1244 || n->is_ConstraintCast()
1245 || n->Opcode() == Op_Return
1246 || n->Opcode() == Op_CMoveP
1247 || n->Opcode() == Op_CMoveN
1248 || n->Opcode() == Op_Rethrow
1249 || n->is_MemBar()
1250 || n->Opcode() == Op_Conv2B
1251 || n->Opcode() == Op_SafePoint
1252 || n->is_CallJava()
1253 || n->Opcode() == Op_Unlock
1254 || n->Opcode() == Op_EncodeP
1255 || n->Opcode() == Op_DecodeN) {
1256 // nothing to do
1257 } else {
1258 static struct {
1259 int opcode;
1260 struct {
1261 int pos;
1262 verify_type t;
1263 } inputs[2];
1264 } others[] = {
1265 Op_FastLock,
1266 { { 1, ShenandoahLoad }, { -1, ShenandoahNone} },
1267 Op_Lock,
1268 { { TypeFunc::Parms, ShenandoahLoad }, { -1, ShenandoahNone} },
1269 Op_ArrayCopy,
1270 { { ArrayCopyNode::Src, ShenandoahLoad }, { ArrayCopyNode::Dest, ShenandoahStore } },
1271 Op_StrCompressedCopy,
1272 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
1273 Op_StrInflatedCopy,
1274 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
1275 Op_AryEq,
1276 { { 2, ShenandoahLoad }, { 3, ShenandoahLoad } },
1277 Op_StrIndexOf,
1278 { { 2, ShenandoahLoad }, { 4, ShenandoahLoad } },
1279 Op_StrComp,
1280 { { 2, ShenandoahLoad }, { 4, ShenandoahLoad } },
1281 Op_StrEquals,
1282 { { 2, ShenandoahLoad }, { 3, ShenandoahLoad } },
1283 Op_EncodeISOArray,
1284 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
1285 Op_HasNegatives,
1286 { { 2, ShenandoahLoad }, { -1, ShenandoahNone} },
1287 Op_CastP2X,
1288 { { 1, ShenandoahLoad }, { -1, ShenandoahNone} },
1289 Op_StrIndexOfChar,
1290 { { 2, ShenandoahLoad }, { -1, ShenandoahNone } },
1291 };
1292
1293 const int others_len = sizeof(others) / sizeof(others[0]);
1294 int i = 0;
1295 for (; i < others_len; i++) {
1296 if (others[i].opcode == n->Opcode()) {
1297 break;
1298 }
1299 }
1300 uint stop = n->is_Call() ? n->as_Call()->tf()->domain()->cnt() : n->req();
1301 if (i != others_len) {
1302 const uint inputs_len = sizeof(others[0].inputs) / sizeof(others[0].inputs[0]);
1303 for (uint j = 0; j < inputs_len; j++) {
1304 int pos = others[i].inputs[j].pos;
1305 if (pos == -1) {
1306 break;
1307 }
1308 if (!ShenandoahBarrierNode::verify_helper(n->in(pos), phis, visited, others[i].inputs[j].t, trace, barriers_used)) {
1309 report_verify_failure("Shenandoah verification: intrinsic calls should have barriers", n);
1310 }
1311 }
1312 for (uint j = 1; j < stop; j++) {
1313 if (n->in(j) != NULL && n->in(j)->bottom_type()->make_ptr() &&
1314 n->in(j)->bottom_type()->make_ptr()->make_oopptr()) {
1315 uint k = 0;
1316 for (; k < inputs_len && others[i].inputs[k].pos != (int)j; k++);
1317 if (k == inputs_len) {
1318 fatal("arg %d for node %s not covered", j, n->Name());
1319 }
1320 }
1321 }
1322 } else {
1323 for (uint j = 1; j < stop; j++) {
1324 if (n->in(j) != NULL && n->in(j)->bottom_type()->make_ptr() &&
1325 n->in(j)->bottom_type()->make_ptr()->make_oopptr()) {
1326 fatal("%s not covered", n->Name());
1327 }
1328 }
1329 }
1330 }
1331
1332 if (n->is_SafePoint()) {
1333 SafePointNode* sfpt = n->as_SafePoint();
1334 if (verify_no_useless_barrier && sfpt->jvms() != NULL) {
1335 for (uint i = sfpt->jvms()->scloff(); i < sfpt->jvms()->endoff(); i++) {
1336 if (!ShenandoahBarrierNode::verify_helper(sfpt->in(i), phis, visited, ShenandoahLoad, trace, barriers_used)) {
1337 phis.clear();
1338 visited.Reset();
1339 }
1340 }
1341 }
1342 }
1343 for( uint i = 0; i < n->len(); ++i ) {
1344 Node *m = n->in(i);
1345 if (m == NULL) continue;
1346
1347 // In most cases, inputs should be known to be non null. If it's
1348 // not the case, it could be a missing cast_not_null() in an
1349 // intrinsic or support might be needed in AddPNode::Ideal() to
1350 // avoid a NULL+offset input.
1351 if (!(n->is_Phi() ||
1352 (n->is_SafePoint() && (!n->is_CallRuntime() || !strcmp(n->as_Call()->_name, "g1_wb_pre") || !strcmp(n->as_Call()->_name, "unsafe_arraycopy"))) ||
1353 n->Opcode() == Op_CmpP ||
1354 n->Opcode() == Op_CmpN ||
1355 (n->Opcode() == Op_StoreP && i == StoreNode::ValueIn) ||
1356 (n->Opcode() == Op_StoreN && i == StoreNode::ValueIn) ||
1357 n->is_ConstraintCast() ||
1358 n->Opcode() == Op_Return ||
1359 n->Opcode() == Op_Conv2B ||
1360 n->is_AddP() ||
1361 n->Opcode() == Op_CMoveP ||
1362 n->Opcode() == Op_CMoveN ||
1363 n->Opcode() == Op_Rethrow ||
1364 n->is_MemBar() ||
1365 n->is_Mem() ||
1366 n->Opcode() == Op_AryEq ||
1367 n->Opcode() == Op_SCMemProj ||
1368 n->Opcode() == Op_EncodeP ||
1369 n->Opcode() == Op_DecodeN)) {
1370 if (m->bottom_type()->make_oopptr() && m->bottom_type()->make_oopptr()->meet(TypePtr::NULL_PTR) == m->bottom_type()) {
1371 report_verify_failure("Shenandoah verification: null input", n, m);
1372 }
1373 }
1374
1375 wq.push(m);
1376 }
1377 }
1378
1379 if (verify_no_useless_barrier) {
1380 for (int i = 0; i < barriers.length(); i++) {
1381 Node* n = barriers.at(i);
1382 if (!barriers_used.member(n)) {
1383 tty->print("XXX useless barrier"); n->dump(-2);
1384 ShouldNotReachHere();
1385 }
1386 }
1387 }
1388 }
1389 #endif
1390
1391 MergeMemNode* ShenandoahWriteBarrierNode::allocate_merge_mem(Node* mem, int alias, Node* rep_proj, Node* rep_ctrl, PhaseIdealLoop* phase) {
1392 MergeMemNode* mm = MergeMemNode::make(mem);
1393 mm->set_memory_at(alias, rep_proj);
1394 phase->register_new_node(mm, rep_ctrl);
1395 return mm;
1396 }
1397
1398 MergeMemNode* ShenandoahWriteBarrierNode::clone_merge_mem(Node* u, Node* mem, int alias, Node* rep_proj, Node* rep_ctrl, DUIterator& i, PhaseIdealLoop* phase) {
1399 MergeMemNode* newmm = NULL;
1400 MergeMemNode* u_mm = u->as_MergeMem();
1401 Node* c = phase->get_ctrl(u);
1402 if (phase->is_dominator(c, rep_ctrl)) {
1403 c = rep_ctrl;
1404 } else {
1405 assert(phase->is_dominator(rep_ctrl, c), "one must dominate the other");
1406 }
1407 if (u->outcnt() == 1) {
1408 if (u->req() > (uint)alias && u->in(alias) == mem) {
1409 phase->igvn().replace_input_of(u, alias, rep_proj);
1410 --i;
1411 } else {
1412 phase->igvn().rehash_node_delayed(u);
1413 u_mm->set_memory_at(alias, rep_proj);
1414 }
1415 newmm = u_mm;
1416 phase->set_ctrl_and_loop(u, c);
1417 } else {
1418 // can't simply clone u and then change one of its input because
1419 // it adds and then removes an edge which messes with the
1420 // DUIterator
1421 newmm = MergeMemNode::make(u_mm->base_memory());
1422 for (uint j = 0; j < u->req(); j++) {
1423 if (j < newmm->req()) {
1424 if (j == (uint)alias) {
1425 newmm->set_req(j, rep_proj);
1426 } else if (newmm->in(j) != u->in(j)) {
1427 newmm->set_req(j, u->in(j));
1428 }
1429 } else if (j == (uint)alias) {
1430 newmm->add_req(rep_proj);
1431 } else {
1432 newmm->add_req(u->in(j));
1433 }
1434 }
1435 if ((uint)alias >= u->req()) {
1436 newmm->set_memory_at(alias, rep_proj);
1437 }
1438 phase->register_new_node(newmm, c);
1439 }
1440 return newmm;
1441 }
1442
1443 bool ShenandoahWriteBarrierNode::should_process_phi(Node* phi, int alias, Compile* C) {
1444 if (phi->adr_type() == TypePtr::BOTTOM) {
1445 Node* region = phi->in(0);
1446 for (DUIterator_Fast jmax, j = region->fast_outs(jmax); j < jmax; j++) {
1447 Node* uu = region->fast_out(j);
1448 if (uu->is_Phi() && uu != phi && uu->bottom_type() == Type::MEMORY && C->get_alias_index(uu->adr_type()) == alias) {
1449 return false;
1450 }
1451 }
1452 return true;
1453 }
1454 return C->get_alias_index(phi->adr_type()) == alias;
1455 }
1456
1457 bool ShenandoahBarrierNode::is_dominator_same_ctrl(Node*c, Node* d, Node* n, PhaseIdealLoop* phase) {
1458 // That both nodes have the same control is not sufficient to prove
1459 // domination, verify that there's no path from d to n
1460 ResourceMark rm;
1461 Unique_Node_List wq;
1462 wq.push(d);
1463 for (uint next = 0; next < wq.size(); next++) {
1464 Node *m = wq.at(next);
1465 if (m == n) {
1466 return false;
1467 }
1468 if (m->is_Phi() && m->in(0)->is_Loop()) {
1469 assert(phase->ctrl_or_self(m->in(LoopNode::EntryControl)) != c, "following loop entry should lead to new control");
1470 } else {
1471 for (uint i = 0; i < m->req(); i++) {
1472 if (m->in(i) != NULL && phase->ctrl_or_self(m->in(i)) == c) {
1473 wq.push(m->in(i));
1474 }
1475 }
1476 }
1477 }
1478 return true;
1479 }
1480
1481 bool ShenandoahBarrierNode::is_dominator(Node *d_c, Node *n_c, Node* d, Node* n, PhaseIdealLoop* phase) {
1482 if (d_c != n_c) {
1483 return phase->is_dominator(d_c, n_c);
1484 }
1485 return is_dominator_same_ctrl(d_c, d, n, phase);
1486 }
1487
1488 Node* next_mem(Node* mem, int alias) {
1489 Node* res = NULL;
1490 if (mem->is_Proj()) {
1491 res = mem->in(0);
1492 } else if (mem->is_SafePoint() || mem->is_MemBar()) {
1493 res = mem->in(TypeFunc::Memory);
1494 } else if (mem->is_Phi()) {
1495 res = mem->in(1);
1496 } else if (mem->is_ShenandoahBarrier()) {
1497 res = mem->in(ShenandoahBarrierNode::Memory);
1498 } else if (mem->is_MergeMem()) {
1499 res = mem->as_MergeMem()->memory_at(alias);
1500 } else if (mem->is_Store() || mem->is_LoadStore() || mem->is_ClearArray()) {
1501 assert(alias = Compile::AliasIdxRaw, "following raw memory can't lead to a barrier");
1502 res = mem->in(MemNode::Memory);
1503 } else {
1504 #ifdef ASSERT
1505 mem->dump();
1506 #endif
1507 ShouldNotReachHere();
1508 }
1509 return res;
1510 }
1511
1512 bool suitable_mem(Node* mem, Node* old_mem, Node* rep_proj) {
1513 for (DUIterator_Fast imax, i = mem->fast_outs(imax); i < imax; i++) {
1514 Node* u = mem->fast_out(i);
1515 if (u->is_MergeMem()) {
1516 if (u->has_out_with(Op_MergeMem)) {
1517 // too complicated for now
1518 return false;
1519 }
1520 if (old_mem == u && rep_proj->has_out_with(Op_MergeMem)) {
1521 return false;
1522 }
1523 }
1524 if (u->Opcode() == Op_Unlock && mem->is_Proj() && mem->in(0)->Opcode() == Op_MemBarReleaseLock) {
1525 // would require a merge mem between unlock and the
1526 // preceding membar. Would confuse logic that eliminates
1527 // lock/unlock nodes.
1528 return false;
1529 }
1530 }
1531 return true;
1532 }
1533
1534 void ShenandoahWriteBarrierNode::fix_memory_uses(Node* mem, Node* replacement, Node* rep_proj, Node* rep_ctrl, int alias, PhaseIdealLoop* phase) {
1535 uint last =phase-> C->unique();
1536 MergeMemNode* mm = NULL;
1537 assert(mem->bottom_type() == Type::MEMORY, "");
1538 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
1539 Node* u = mem->out(i);
1540 if (u != replacement && u->_idx < last) {
1541 if (u->is_ShenandoahBarrier() && alias != Compile::AliasIdxRaw) {
1542 if (phase->C->get_alias_index(u->adr_type()) == alias && is_dominator(rep_ctrl, phase->ctrl_or_self(u), replacement, u, phase)) {
1543 phase->igvn().replace_input_of(u, u->find_edge(mem), rep_proj);
1544 assert(u->find_edge(mem) == -1, "only one edge");
1545 --i;
1546 }
1547 } else if (u->is_Mem()) {
1548 if (phase->C->get_alias_index(u->adr_type()) == alias && is_dominator(rep_ctrl, phase->ctrl_or_self(u), replacement, u, phase)) {
1549 assert(alias == Compile::AliasIdxRaw , "only raw memory can lead to a memory operation");
1550 phase->igvn().replace_input_of(u, u->find_edge(mem), rep_proj);
1551 assert(u->find_edge(mem) == -1, "only one edge");
1552 --i;
1553 }
1554 } else if (u->is_MergeMem()) {
1555 MergeMemNode* u_mm = u->as_MergeMem();
1556 if (u_mm->memory_at(alias) == mem) {
1557 MergeMemNode* newmm = NULL;
1558 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
1559 Node* uu = u->fast_out(j);
1560 assert(!uu->is_MergeMem(), "chain of MergeMems?");
1561 if (uu->is_Phi()) {
1562 if (should_process_phi(uu, alias, phase->C)) {
1563 Node* region = uu->in(0);
1564 int nb = 0;
1565 for (uint k = 1; k < uu->req(); k++) {
1566 if (uu->in(k) == u && phase->is_dominator(rep_ctrl, region->in(k))) {
1567 if (newmm == NULL) {
1568 newmm = clone_merge_mem(u, mem, alias, rep_proj, rep_ctrl, i, phase);
1569 }
1570 if (newmm != u) {
1571 phase->igvn().replace_input_of(uu, k, newmm);
1572 nb++;
1573 --jmax;
1574 }
1575 }
1576 }
1577 if (nb > 0) {
1578 --j;
1579 }
1580 }
1581 } else {
1582 if (rep_ctrl != uu && is_dominator(rep_ctrl, phase->ctrl_or_self(uu), replacement, uu, phase)) {
1583 if (newmm == NULL) {
1584 newmm = clone_merge_mem(u, mem, alias, rep_proj, rep_ctrl, i, phase);
1585 }
1586 if (newmm != u) {
1587 phase->igvn().replace_input_of(uu, uu->find_edge(u), newmm);
1588 --j, --jmax;
1589 }
1590 }
1591 }
1592 }
1593 }
1594 } else if (u->is_Phi()) {
1595 assert(u->bottom_type() == Type::MEMORY, "what else?");
1596 Node* region = u->in(0);
1597 if (should_process_phi(u, alias, phase->C)) {
1598 bool replaced = false;
1599 for (uint j = 1; j < u->req(); j++) {
1600 if (u->in(j) == mem && phase->is_dominator(rep_ctrl, region->in(j))) {
1601 Node* nnew = rep_proj;
1602 if (u->adr_type() == TypePtr::BOTTOM) {
1603 if (mm == NULL) {
1604 mm = allocate_merge_mem(mem, alias, rep_proj, rep_ctrl, phase);
1605 }
1606 nnew = mm;
1607 }
1608 phase->igvn().replace_input_of(u, j, nnew);
1609 replaced = true;
1610 }
1611 }
1612 if (replaced) {
1613 --i;
1614 }
1615
1616 }
1617 } else if ((u->adr_type() == TypePtr::BOTTOM && u->Opcode() != Op_StrInflatedCopy) ||
1618 u->adr_type() == NULL) {
1619 assert(u->adr_type() != NULL ||
1620 u->Opcode() == Op_Rethrow ||
1621 u->Opcode() == Op_Return ||
1622 u->Opcode() == Op_SafePoint ||
1623 (u->is_CallStaticJava() && u->as_CallStaticJava()->uncommon_trap_request() != 0) ||
1624 (u->is_CallStaticJava() && u->as_CallStaticJava()->_entry_point == OptoRuntime::rethrow_stub()) ||
1625 u->Opcode() == Op_CallLeaf, "");
1626 if (is_dominator(rep_ctrl, phase->ctrl_or_self(u), replacement, u, phase)) {
1627 if (mm == NULL) {
1628 mm = allocate_merge_mem(mem, alias, rep_proj, rep_ctrl, phase);
1629 }
1630 phase->igvn().replace_input_of(u, u->find_edge(mem), mm);
1631 --i;
1632 }
1633 } else if (phase->C->get_alias_index(u->adr_type()) == alias) {
1634 if (is_dominator(rep_ctrl, phase->ctrl_or_self(u), replacement, u, phase)) {
1635 phase->igvn().replace_input_of(u, u->find_edge(mem), rep_proj);
1636 --i;
1637 }
1638 }
1639 }
1640 }
1641 }
1642
1643 Node* ShenandoahBarrierNode::no_branches(Node* c, Node* dom, bool allow_one_proj, PhaseIdealLoop* phase) {
1644 Node* iffproj = NULL;
1645 while (c != dom) {
1646 Node* next = phase->idom(c);
1647 assert(next->unique_ctrl_out() == c || c->is_Proj() || c->is_Region(), "multiple control flow out but no proj or region?");
1648 if (c->is_Region()) {
1649 ResourceMark rm;
1650 Unique_Node_List wq;
1651 wq.push(c);
1652 for (uint i = 0; i < wq.size(); i++) {
1653 Node *n = wq.at(i);
1654 if (n->is_Region()) {
1655 for (uint j = 1; j < n->req(); j++) {
1656 if (n->in(j) != next) {
1657 wq.push(n->in(j));
1658 }
1659 }
1660 } else {
1661 if (n->in(0) != next) {
1662 wq.push(n->in(0));
1663 }
1664 }
1665 }
1666 for (DUIterator_Fast imax, i = next->fast_outs(imax); i < imax; i++) {
1667 Node* u = next->fast_out(i);
1668 if (u->is_CFG()) {
1669 if (!wq.member(u)) {
1670 return NodeSentinel;
1671 }
1672 }
1673 }
1674
1675 } else if (c->is_Proj()) {
1676 if (c->is_IfProj()) {
1677 if (c->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none) != NULL) {
1678 // continue;
1679 } else {
1680 if (!allow_one_proj) {
1681 return NodeSentinel;
1682 }
1683 if (iffproj == NULL) {
1684 iffproj = c;
1685 } else {
1686 return NodeSentinel;
1687 }
1688 }
1689 } else if (c->Opcode() == Op_JumpProj) {
1690 return NodeSentinel; // unsupported
1691 } else if (c->Opcode() == Op_CatchProj) {
1692 return NodeSentinel; // unsupported
1693 } else if (c->Opcode() == Op_CProj && next->Opcode() == Op_NeverBranch) {
1694 return NodeSentinel; // unsupported
1695 } else {
1696 assert(next->unique_ctrl_out() == c, "unsupported branch pattern");
1697 }
1698 }
1699 c = next;
1700 }
1701 return iffproj;
1702 }
1703
1704 #ifdef ASSERT
1705 void ShenandoahWriteBarrierNode::memory_dominates_all_paths_helper(Node* c, Node* rep_ctrl, Unique_Node_List& controls, PhaseIdealLoop* phase) {
1706 const bool trace = false;
1707 if (trace) { tty->print("X control is"); c->dump(); }
1708
1709 uint start = controls.size();
1710 controls.push(c);
1711 for (uint i = start; i < controls.size(); i++) {
1712 Node *n = controls.at(i);
1713
1714 if (trace) { tty->print("X from"); n->dump(); }
1715
1716 if (n == rep_ctrl) {
1717 continue;
1718 }
1719
1720 if (n->is_Proj()) {
1721 Node* n_dom = n->in(0);
1722 IdealLoopTree* n_dom_loop = phase->get_loop(n_dom);
1723 if (n->is_IfProj() && n_dom->outcnt() == 2) {
1724 n_dom_loop = phase->get_loop(n_dom->as_If()->proj_out(n->as_Proj()->_con == 0 ? 1 : 0));
1725 }
1726 if (n_dom_loop != phase->ltree_root()) {
1727 Node* tail = n_dom_loop->tail();
1728 if (tail->is_Region()) {
1729 for (uint j = 1; j < tail->req(); j++) {
1730 if (phase->is_dominator(n_dom, tail->in(j)) && !phase->is_dominator(n, tail->in(j))) {
1731 assert(phase->is_dominator(rep_ctrl, tail->in(j)), "why are we here?");
1732 // entering loop from below, mark backedge
1733 if (trace) { tty->print("X pushing backedge"); tail->in(j)->dump(); }
1734 controls.push(tail->in(j));
1735 //assert(n->in(0) == n_dom, "strange flow control");
1736 }
1737 }
1738 } else if (phase->get_loop(n) != n_dom_loop && phase->is_dominator(n_dom, tail)) {
1739 // entering loop from below, mark backedge
1740 if (trace) { tty->print("X pushing backedge"); tail->dump(); }
1741 controls.push(tail);
1742 //assert(n->in(0) == n_dom, "strange flow control");
1743 }
1744 }
1745 }
1746
1747 if (n->is_Loop()) {
1748 Node* c = n->in(LoopNode::EntryControl);
1749 if (trace) { tty->print("X pushing"); c->dump(); }
1750 controls.push(c);
1751 } else if (n->is_Region()) {
1752 for (uint i = 1; i < n->req(); i++) {
1753 Node* c = n->in(i);
1754 if (trace) { tty->print("X pushing"); c->dump(); }
1755 controls.push(c);
1756 }
1757 } else {
1758 Node* c = n->in(0);
1759 if (trace) { tty->print("X pushing"); c->dump(); }
1760 controls.push(c);
1761 }
1762 }
1763 }
1764
1765 bool ShenandoahWriteBarrierNode::memory_dominates_all_paths(Node* mem, Node* rep_ctrl, int alias, PhaseIdealLoop* phase) {
1766 const bool trace = false;
1767 if (trace) {
1768 tty->print("XXX mem is"); mem->dump();
1769 tty->print("XXX rep ctrl is"); rep_ctrl->dump();
1770 tty->print_cr("XXX alias is %d", alias);
1771 }
1772 ResourceMark rm;
1773 Unique_Node_List wq;
1774 Unique_Node_List controls;
1775 wq.push(mem);
1776 for (uint next = 0; next < wq.size(); next++) {
1777 Node *nn = wq.at(next);
1778 if (trace) { tty->print("XX from mem"); nn->dump(); }
1779 assert(nn->bottom_type() == Type::MEMORY, "memory only");
1780
1781 if (nn->is_Phi()) {
1782 Node* r = nn->in(0);
1783 for (DUIterator_Fast jmax, j = r->fast_outs(jmax); j < jmax; j++) {
1784 Node* u = r->fast_out(j);
1785 if (u->is_Phi() && u->bottom_type() == Type::MEMORY && u != nn &&
1786 (u->adr_type() == TypePtr::BOTTOM || phase->C->get_alias_index(u->adr_type()) == alias)) {
1787 if (trace) { tty->print("XX Next mem (other phi)"); u->dump(); }
1788 wq.push(u);
1789 }
1790 }
1791 }
1792
1793 for (DUIterator_Fast imax, i = nn->fast_outs(imax); i < imax; i++) {
1794 Node* use = nn->fast_out(i);
1795
1796 if (trace) { tty->print("XX use %p", use->adr_type()); use->dump(); }
1797 if (use->is_CFG()) {
1798 assert(use->in(TypeFunc::Memory) == nn, "bad cfg node");
1799 Node* c = use->in(0);
1800 if (phase->is_dominator(rep_ctrl, c)) {
1801 memory_dominates_all_paths_helper(c, rep_ctrl, controls, phase);
1802 } else if (use->is_CallStaticJava() && use->as_CallStaticJava()->uncommon_trap_request() != 0 && c->is_Region()) {
1803 Node* region = c;
1804 if (trace) { tty->print("XX unc region"); region->dump(); }
1805 for (uint j = 1; j < region->req(); j++) {
1806 if (phase->is_dominator(rep_ctrl, region->in(j))) {
1807 if (trace) { tty->print("XX unc follows"); region->in(j)->dump(); }
1808 memory_dominates_all_paths_helper(region->in(j), rep_ctrl, controls, phase);
1809 }
1810 }
1811 }
1812 //continue;
1813 } else if (use->is_Phi()) {
1814 assert(use->bottom_type() == Type::MEMORY, "bad phi");
1815 if ((use->adr_type() == TypePtr::BOTTOM /*&& !shenandoah_has_alias_phi(C, use, alias)*/) ||
1816 phase->C->get_alias_index(use->adr_type()) == alias) {
1817 for (uint j = 1; j < use->req(); j++) {
1818 if (use->in(j) == nn) {
1819 Node* c = use->in(0)->in(j);
1820 if (phase->is_dominator(rep_ctrl, c)) {
1821 memory_dominates_all_paths_helper(c, rep_ctrl, controls, phase);
1822 }
1823 }
1824 }
1825 }
1826 // continue;
1827 }
1828
1829 if (use->is_MergeMem()) {
1830 if (use->as_MergeMem()->memory_at(alias) == nn) {
1831 if (trace) { tty->print("XX Next mem"); use->dump(); }
1832 // follow the memory edges
1833 wq.push(use);
1834 }
1835 } else if (use->is_Phi()) {
1836 assert(use->bottom_type() == Type::MEMORY, "bad phi");
1837 if ((use->adr_type() == TypePtr::BOTTOM /*&& !shenandoah_has_alias_phi(C, use, alias)*/) ||
1838 phase->C->get_alias_index(use->adr_type()) == alias) {
1839 if (trace) { tty->print("XX Next mem"); use->dump(); }
1840 // follow the memory edges
1841 wq.push(use);
1842 }
1843 } else if (use->bottom_type() == Type::MEMORY &&
1844 (use->adr_type() == TypePtr::BOTTOM || phase->C->get_alias_index(use->adr_type()) == alias)) {
1845 if (trace) { tty->print("XX Next mem"); use->dump(); }
1846 // follow the memory edges
1847 wq.push(use);
1848 } else if ((use->is_SafePoint() || use->is_MemBar()) &&
1849 (use->adr_type() == TypePtr::BOTTOM || phase->C->get_alias_index(use->adr_type()) == alias)) {
1850 for (DUIterator_Fast jmax, j = use->fast_outs(jmax); j < jmax; j++) {
1851 Node* u = use->fast_out(j);
1852 if (u->bottom_type() == Type::MEMORY) {
1853 if (trace) { tty->print("XX Next mem"); u->dump(); }
1854 // follow the memory edges
1855 wq.push(u);
1856 }
1857 }
1858 } else if (use->Opcode() == Op_ShenandoahWriteBarrier && phase->C->get_alias_index(use->adr_type()) == alias) {
1859 Node* m = use->find_out_with(Op_ShenandoahWBMemProj);
1860 if (m != NULL) {
1861 if (trace) { tty->print("XX Next mem"); m->dump(); }
1862 // follow the memory edges
1863 wq.push(m);
1864 }
1865 }
1866 }
1867 }
1868
1869 if (controls.size() == 0) {
1870 return false;
1871 }
1872
1873 for (uint i = 0; i < controls.size(); i++) {
1874 Node *n = controls.at(i);
1875
1876 if (trace) { tty->print("X checking"); n->dump(); }
1877
1878 if (n->unique_ctrl_out() != NULL) {
1879 continue;
1880 }
1881
1882 if (n->Opcode() == Op_NeverBranch) {
1883 Node* taken = n->as_Multi()->proj_out(0);
1884 if (!controls.member(taken)) {
1885 if (trace) { tty->print("X not seen"); taken->dump(); }
1886 return false;
1887 }
1888 continue;
1889 }
1890
1891 for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
1892 Node* u = n->fast_out(j);
1893
1894 if (u->is_CFG()) {
1895 if (!controls.member(u)) {
1896 if (u->is_Proj() && u->as_Proj()->is_uncommon_trap_proj(Deoptimization::Reason_none)) {
1897 if (trace) { tty->print("X not seen but unc"); u->dump(); }
1898 } else {
1899 Node* c = u;
1900 do {
1901 c = c->unique_ctrl_out();
1902 } while (c != NULL && c->is_Region());
1903 if (c != NULL && c->Opcode() == Op_Halt) {
1904 if (trace) { tty->print("X not seen but halt"); c->dump(); }
1905 } else {
1906 if (trace) { tty->print("X not seen"); u->dump(); }
1907 return false;
1908 }
1909 }
1910 } else {
1911 if (trace) { tty->print("X seen"); u->dump(); }
1912 }
1913 }
1914 }
1915 }
1916 return true;
1917 }
1918 #endif
1919
1920 static bool has_mem_phi(Compile* C, Node* region, int alias) {
1921 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
1922 Node* use = region->fast_out(i);
1923 if (use->is_Phi() && use->bottom_type() == Type::MEMORY &&
1924 (C->get_alias_index(use->adr_type()) == alias)) {
1925 return true;
1926 }
1927 }
1928 return false;
1929 }
1930
1931 bool ShenandoahWriteBarrierNode::fix_mem_phis_helper(Node* c, Node* mem, Node* mem_ctrl, Node* rep_ctrl, int alias, VectorSet& controls, GrowableArray<Node*>& regions, PhaseIdealLoop* phase) {
1932 const bool trace = false;
1933 Node_List wq;
1934 wq.push(c);
1935
1936 #ifdef ASSERT
1937 if (trace) { tty->print("YYY from"); c->dump(); }
1938 if (trace) { tty->print("YYY with mem"); mem->dump(); }
1939 #endif
1940
1941 while(wq.size() > 0) {
1942 c = wq.pop();
1943
1944 while (!c->is_Region() || c->is_Loop()) {
1945 #ifdef ASSERT
1946 if (trace) { tty->print("YYY"); c->dump(); }
1947 #endif
1948 assert(c->is_CFG(), "node should be control node");
1949 if (c == mem_ctrl || phase->is_dominator(c, rep_ctrl)) {
1950 c = NULL;
1951 break;
1952 } else if (c->is_Loop()) {
1953 c = c->in(LoopNode::EntryControl);
1954 } else {
1955 c = c->in(0);
1956 }
1957 }
1958 if (c == NULL) {
1959 continue;
1960 }
1961
1962 #ifdef ASSERT
1963 if (trace) { tty->print("YYY new region"); c->dump(); }
1964 #endif
1965
1966 bool has_phi = has_mem_phi(phase->C, c, alias);
1967 if (!has_phi) {
1968
1969 Node* m_ctrl = NULL;
1970 Node* m = dom_mem(mem, c, alias, m_ctrl, phase);
1971 if (m == NULL) {
1972 return false;
1973 }
1974
1975 #ifdef ASSERT
1976 if (trace) { tty->print("YYY mem "); m->dump(); }
1977 #endif
1978
1979 if (controls.test(c->_idx)) {
1980 int i;
1981 for (i = 0; i < regions.length() && regions.at(i) != c; i+=2) {
1982 // deliberately empty, rolling over the regions
1983 }
1984 assert(i < regions.length(), "missing region");
1985 Node* prev_m = regions.at(i+1);
1986 if (prev_m == m) {
1987 continue;
1988 }
1989 #ifdef ASSERT
1990 if (trace) { tty->print("YYY prev mem "); prev_m->dump(); }
1991 #endif
1992 Node* prev_m_ctrl = phase->ctrl_or_self(prev_m);
1993 assert(is_dominator(m_ctrl, prev_m_ctrl, m, prev_m, phase) ||
1994 is_dominator(prev_m_ctrl, m_ctrl, prev_m, m, phase), "one should dominate the other");
1995 if (is_dominator(m_ctrl, prev_m_ctrl, m, prev_m, phase)) {
1996 continue;
1997 }
1998 #ifdef ASSERT
1999 if (trace) { tty->print("YYY Fixing "); c->dump(); }
2000 #endif
2001 regions.at_put(i+1, m);
2002 } else {
2003 #ifdef ASSERT
2004 if (trace) { tty->print("YYY Pushing "); c->dump(); }
2005 #endif
2006 regions.push(c);
2007 regions.push(m);
2008 }
2009 } else {
2010 continue;
2011 }
2012
2013 controls.set(c->_idx);
2014
2015 for (uint i = 1; i < c->req(); i++) {
2016 wq.push(c->in(i));
2017 }
2018 }
2019 return true;
2020 }
2021
2022
2023 bool ShenandoahWriteBarrierNode::fix_mem_phis(Node* mem, Node* mem_ctrl, Node* rep_ctrl, int alias, PhaseIdealLoop* phase) {
2024 GrowableArray<Node*> regions;
2025 VectorSet controls(Thread::current()->resource_area());
2026 const bool trace = false;
2027
2028 #ifdef ASSERT
2029 if (trace) { tty->print("YYY mem is "); mem->dump(); }
2030 if (trace) { tty->print("YYY mem ctrl is "); mem_ctrl->dump(); }
2031 if (trace) { tty->print("YYY rep ctrl is "); rep_ctrl->dump(); }
2032 if (trace) { tty->print_cr("YYY alias is %d", alias); }
2033 #endif
2034
2035 // Walk memory edges from mem until we hit a memory point where
2036 // control is known then follow the control up looking for regions
2037 // with no memory Phi for alias
2038 Unique_Node_List wq;
2039 wq.push(mem);
2040
2041 for (uint next = 0; next < wq.size(); next++) {
2042 Node *n = wq.at(next);
2043 #ifdef ASSERT
2044 if (trace) { tty->print("YYY from (2) "); n->dump(); }
2045 #endif
2046 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2047 Node* u = n->fast_out(i);
2048 #ifdef ASSERT
2049 if (trace) { tty->print("YYY processing "); u->dump(); }
2050 #endif
2051 if (u->is_Phi()) {
2052 assert(u->bottom_type() == Type::MEMORY, "strange memory graph");
2053 if (should_process_phi(u, alias, phase->C)) {
2054 for (uint j = 1; j < u->req(); j++) {
2055 if (u->in(j) == n) {
2056 Node *c = u->in(0)->in(j);
2057 if (!fix_mem_phis_helper(c, n, mem_ctrl, rep_ctrl, alias, controls, regions, phase)) {
2058 return false;
2059 }
2060 }
2061 }
2062 }
2063 #ifdef ASSERT
2064 } else if (u->is_CallStaticJava() && u->as_CallStaticJava()->uncommon_trap_request() != 0) {
2065 if (!fix_mem_phis_helper(u->in(0), n, mem_ctrl, rep_ctrl, alias, controls, regions, phase)) {
2066 return false;
2067 }
2068 #endif
2069 } else if ((u->is_CFG() && u->adr_type() == TypePtr::BOTTOM) || u->Opcode() == Op_Rethrow || u->Opcode() == Op_Return) {
2070 if (!fix_mem_phis_helper(u->in(0), n, mem_ctrl, rep_ctrl, alias, controls, regions, phase)) {
2071 return false;
2072 }
2073 } else if (u->is_MergeMem() && u->as_MergeMem()->memory_at(alias) == n) {
2074 wq.push(u);
2075 } else if (u->Opcode() == Op_ShenandoahWriteBarrier && phase->C->get_alias_index(u->adr_type()) == alias) {
2076 Node* m = u->find_out_with(Op_ShenandoahWBMemProj);
2077 if (m != NULL) {
2078 wq.push(m);
2079 }
2080 }
2081 }
2082 }
2083 #ifdef ASSERT
2084 if (trace) {
2085 tty->print_cr("XXXXXXXXXXXXXXXXXXXX");
2086 for (int i = 0; i < regions.length(); i++) {
2087 Node* r = regions.at(i);
2088 tty->print("%d", i); r->dump();
2089 }
2090 tty->print_cr("XXXXXXXXXXXXXXXXXXXX");
2091 }
2092 #endif
2093
2094 if (regions.length() == 0) {
2095 return true;
2096 }
2097
2098 {
2099 int i = 0;
2100 for (; i < regions.length(); i+=2) {
2101 Node* region = regions.at(i);
2102 bool has_phi = false;
2103 for (DUIterator_Fast jmax, j = region->fast_outs(jmax); j < jmax && !has_phi; j++) {
2104 Node* u = region->fast_out(j);
2105 if (u->is_Phi() && u->bottom_type() == Type::MEMORY &&
2106 (u->adr_type() == TypePtr::BOTTOM || phase->C->get_alias_index(u->adr_type()) == alias)) {
2107 has_phi = true;
2108 }
2109 }
2110 if (!has_phi) {
2111 break;
2112 }
2113 }
2114 if (i == regions.length()) {
2115 return true;
2116 }
2117 }
2118
2119 // Try to restrict the update to path that post dominates rep_ctrl
2120 int k = 0;
2121 int start = 0;
2122 int end = 0;
2123 do {
2124 start = end;
2125 end = k;
2126 for (int i = end; i < regions.length(); i+=2) {
2127 Node* r = regions.at(i);
2128 int prev = k;
2129 for (uint j = 1; j < r->req() && prev == k; j++) {
2130 if (end == 0) {
2131 if (phase->is_dominator(rep_ctrl, r->in(j))) {
2132 Node* mem = regions.at(i+1);
2133 regions.at_put(i, regions.at(k));
2134 regions.at_put(i+1, regions.at(k+1));
2135 regions.at_put(k, r);
2136 regions.at_put(k+1, mem);
2137 k+=2;
2138 }
2139 } else {
2140 for (int l = start; l < end && prev == k; l+=2) {
2141 Node* r2 = regions.at(l);
2142 if (phase->is_dominator(r2, r->in(j))) {
2143 Node* mem = regions.at(i+1);
2144 regions.at_put(i, regions.at(k));
2145 regions.at_put(i+1, regions.at(k+1));
2146 regions.at_put(k, r);
2147 regions.at_put(k+1, mem);
2148 k+=2;
2149 }
2150 }
2151 }
2152 }
2153 }
2154 #ifdef ASSERT
2155 if (trace) { tty->print_cr("k = %d start = %d end = %d", k, start, end); }
2156 #endif
2157 } while(k != end);
2158
2159 #ifdef ASSERT
2160 if (end != regions.length()) {
2161 if (trace) { tty->print_cr("Compacting %d -> %d", regions.length(), end); }
2162 }
2163 #endif
2164 regions.trunc_to(end);
2165
2166 #ifdef ASSERT
2167 if (trace) {
2168 tty->print_cr("XXXXXXXXXXXXXXXXXXXX");
2169 for (int i = 0; i < regions.length(); i++) {
2170 Node* r = regions.at(i);
2171 tty->print("%d", i); r->dump();
2172 }
2173 tty->print_cr("XXXXXXXXXXXXXXXXXXXX");
2174 }
2175 #endif
2176
2177 // Creating new phis must be done in post order
2178 while (regions.length() > 0) {
2179 int i = 0;
2180 for (; i < regions.length(); i+=2) {
2181 Node* r1 = regions.at(i);
2182 bool is_dom = false;
2183 for (int j = 0; j < regions.length() && !is_dom; j+=2) {
2184 if (i != j) {
2185 Node* r2 = regions.at(j);
2186 for (uint k = 1; k < r2->req() && !is_dom; k++) {
2187 if (phase->is_dominator(r1, r2->in(k))) {
2188 is_dom = true;
2189 }
2190 }
2191 }
2192 }
2193 if (!is_dom) {
2194 break;
2195 }
2196 }
2197 assert(i < regions.length(), "need one");
2198 Node* r = regions.at(i);
2199 Node* m = regions.at(i+1);
2200 regions.delete_at(i+1);
2201 regions.delete_at(i);
2202
2203 if (!suitable_mem(m, NULL, NULL)) {
2204 return false;
2205 }
2206 Node* phi = PhiNode::make(r, m, Type::MEMORY, phase->C->get_adr_type(alias));
2207 #ifdef ASSERT
2208 if (trace) { tty->print("YYY Adding new mem phi "); phi->dump(); }
2209 #endif
2210 phase->register_new_node(phi, r);
2211
2212 fix_memory_uses(m, phi, phi, r, phase->C->get_alias_index(phi->adr_type()), phase);
2213 assert(phi->outcnt() != 0, "new proj should have uses");
2214 if (phi->outcnt() == 0) {
2215 phase->igvn().remove_dead_node(phi);
2216 }
2217 }
2218
2219 return true;
2220 }
2221
2222 Node* ShenandoahBarrierNode::dom_mem(Node* mem, Node*& mem_ctrl, Node* n, Node* rep_ctrl, int alias, PhaseIdealLoop* phase) {
2223 ResourceMark rm;
2224 VectorSet wq(Thread::current()->resource_area());
2225 wq.set(mem->_idx);
2226 mem_ctrl = phase->get_ctrl(mem);
2227 while (!is_dominator(mem_ctrl, rep_ctrl, mem, n, phase)) {
2228 mem = next_mem(mem, alias);
2229 if (wq.test_set(mem->_idx)) {
2230 return NULL; // hit an unexpected loop
2231 }
2232 mem_ctrl = phase->ctrl_or_self(mem);
2233 }
2234 if (mem->is_MergeMem()) {
2235 mem = mem->as_MergeMem()->memory_at(alias);
2236 mem_ctrl = phase->ctrl_or_self(mem);
2237 }
2238 return mem;
2239 }
2240
2241 Node* ShenandoahBarrierNode::dom_mem(Node* mem, Node* ctrl, int alias, Node*& mem_ctrl, PhaseIdealLoop* phase) {
2242 ResourceMark rm;
2243 VectorSet wq(Thread::current()->resource_area());
2244 wq.set(mem->_idx);
2245 mem_ctrl = phase->ctrl_or_self(mem);
2246 while (!phase->is_dominator(mem_ctrl, ctrl) || mem_ctrl == ctrl) {
2247 mem = next_mem(mem, alias);
2248 if (wq.test_set(mem->_idx)) {
2249 return NULL;
2250 }
2251 mem_ctrl = phase->ctrl_or_self(mem);
2252 }
2253 if (mem->is_MergeMem()) {
2254 mem = mem->as_MergeMem()->memory_at(alias);
2255 mem_ctrl = phase->ctrl_or_self(mem);
2256 }
2257 return mem;
2258 }
2259
2260 Node* ShenandoahBarrierNode::try_common(Node *n_ctrl, PhaseIdealLoop* phase) {
2261 if (!phase->C->has_irreducible_loop()) {
2262 // We look for a write barrier whose memory edge dominates n
2263 // Either the replacement write barrier dominates n or we have,
2264 // for instance:
2265 // if ( ) {
2266 // read barrier n
2267 // } else {
2268 // write barrier
2269 // }
2270 // in which case replacing n by the write barrier causes the write
2271 // barrier to move above the if() and the memory Phi that merges
2272 // the memory state for both branches must be updated so both
2273 // inputs become the write barrier's memory projection (and the
2274 // Phi is optimized out) otherwise we risk loosing a memory
2275 // dependency.
2276 // Once we find a replacement write barrier, the code below fixes
2277 // the memory graph in cases like the one above.
2278 Node* val = in(ValueIn);
2279 Node* val_ctrl = phase->get_ctrl(val);
2280 Node* n_proj = find_out_with(Op_ShenandoahWBMemProj);
2281 Node* replacement = NULL;
2282 int alias = phase->C->get_alias_index(adr_type());
2283 Node* rep_ctrl = NULL;
2284 for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax && replacement == NULL; i++) {
2285 Node* u = val->fast_out(i);
2286 if (u != this && u->Opcode() == Op_ShenandoahWriteBarrier) {
2287 Node* u_mem = u->in(Memory);
2288 Node* u_proj = u->find_out_with(Op_ShenandoahWBMemProj);
2289 Node* u_ctrl = phase->get_ctrl(u);
2290 Node* u_mem_ctrl = phase->get_ctrl(u_mem);
2291 IdealLoopTree* n_loop = phase->get_loop(n_ctrl);
2292 IdealLoopTree* u_loop = phase->get_loop(u_ctrl);
2293
2294 Node* ctrl = phase->dom_lca(u_ctrl, n_ctrl);
2295
2296 if (ctrl->is_Proj() &&
2297 ctrl->in(0)->is_Call() &&
2298 ctrl->unique_ctrl_out() != NULL &&
2299 ctrl->unique_ctrl_out()->Opcode() == Op_Catch &&
2300 !phase->is_dominator(val_ctrl, ctrl->in(0)->in(0))) {
2301 continue;
2302 }
2303
2304 if (Opcode() == Op_ShenandoahWriteBarrier && u_proj == NULL && n_proj != NULL) {
2305 continue;
2306 }
2307
2308 IdealLoopTree* loop = phase->get_loop(ctrl);
2309
2310 // We don't want to move a write barrier in a loop
2311 // If the LCA is in a inner loop, try a control out of loop if possible
2312 bool loop_ok = true;
2313 while (!loop->is_member(u_loop) && (Opcode() != Op_ShenandoahWriteBarrier || !loop->is_member(n_loop))) {
2314 ctrl = phase->idom(ctrl);
2315 if (ctrl != val_ctrl && phase->is_dominator(ctrl, val_ctrl)) {
2316 loop_ok = false;
2317 break;
2318 }
2319 loop = phase->get_loop(ctrl);
2320 }
2321
2322 if (loop_ok) {
2323 if (ShenandoahDontIncreaseWBFreq) {
2324 Node* u_iffproj = no_branches(u_ctrl, ctrl, true, phase);
2325 if (Opcode() == Op_ShenandoahWriteBarrier) {
2326 Node* n_iffproj = no_branches(n_ctrl, ctrl, true, phase);
2327 if (u_iffproj == NULL || n_iffproj == NULL) {
2328 replacement = u;
2329 rep_ctrl = ctrl;
2330 } else if (u_iffproj != NodeSentinel && n_iffproj != NodeSentinel && u_iffproj->in(0) == n_iffproj->in(0)) {
2331 replacement = u;
2332 rep_ctrl = ctrl;
2333 }
2334 } else if (u_iffproj == NULL) {
2335 replacement = u;
2336 rep_ctrl = ctrl;
2337 }
2338 } else {
2339 replacement = u;
2340 rep_ctrl = ctrl;
2341 }
2342 }
2343 }
2344 }
2345 if (replacement != NULL) {
2346 if (rep_ctrl->is_Proj() &&
2347 rep_ctrl->in(0)->is_Call() &&
2348 rep_ctrl->unique_ctrl_out() != NULL &&
2349 rep_ctrl->unique_ctrl_out()->Opcode() == Op_Catch) {
2350 rep_ctrl = rep_ctrl->in(0)->in(0);
2351 assert(phase->is_dominator(val_ctrl, rep_ctrl), "bad control");
2352 } else {
2353 LoopNode* c = ShenandoahWriteBarrierNode::try_move_before_pre_loop(rep_ctrl, val_ctrl, phase);
2354 if (c != NULL) {
2355 rep_ctrl = ShenandoahWriteBarrierNode::move_above_predicates(c, val_ctrl, phase);
2356 } else {
2357 while (rep_ctrl->is_IfProj()) {
2358 CallStaticJavaNode* unc = rep_ctrl->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none);
2359 if (unc != NULL) {
2360 int req = unc->uncommon_trap_request();
2361 Deoptimization::DeoptReason trap_reason = Deoptimization::trap_request_reason(req);
2362 if ((trap_reason == Deoptimization::Reason_loop_limit_check ||
2363 trap_reason == Deoptimization::Reason_predicate) && phase->is_dominator(val_ctrl, rep_ctrl->in(0)->in(0))) {
2364 rep_ctrl = rep_ctrl->in(0)->in(0);
2365 continue;
2366 }
2367 }
2368 break;
2369 }
2370 }
2371 }
2372
2373 Node* mem = replacement->in(Memory);
2374 Node* old_mem = mem;
2375 Node* rep_proj = replacement->find_out_with(Op_ShenandoahWBMemProj);
2376 {
2377 Node* mem_ctrl = NULL;
2378
2379 mem = dom_mem(mem, mem_ctrl, this, rep_ctrl, alias, phase);
2380 if (mem == NULL) {
2381 return NULL;
2382 }
2383
2384 // Add a memory Phi for the slice of the write barrier to any
2385 // region that post dominates rep_ctrl and doesn't have one
2386 // already.
2387 if (rep_proj != NULL && !ShenandoahWriteBarrierNode::fix_mem_phis(mem, mem_ctrl, rep_ctrl, alias, phase)) {
2388 return NULL;
2389 }
2390
2391 assert(!ShenandoahVerifyOptoBarriers || ShenandoahWriteBarrierNode::memory_dominates_all_paths(mem, rep_ctrl, alias, phase), "can't fix the memory graph");
2392 }
2393 assert(phase->igvn().type(mem) == Type::MEMORY, "not memory");
2394
2395 if (rep_proj != NULL) {
2396 Node* old_mem = replacement->in(Memory);
2397 if (!suitable_mem(mem, old_mem, rep_proj)) {
2398 return NULL;
2399 }
2400
2401 if (replacement->in(Memory) != mem) {
2402 // tty->print("XXX setting memory of"); replacement->dump();
2403 // tty->print("XXX to"); mem->dump();
2404 for (DUIterator_Last imin, i = rep_proj->last_outs(imin); i >= imin; ) {
2405 Node* u = rep_proj->last_out(i);
2406 phase->igvn().rehash_node_delayed(u);
2407 int uses_found = u->replace_edge(rep_proj, old_mem);
2408 i -= uses_found;
2409 }
2410 phase->igvn().replace_input_of(replacement, Memory, mem);
2411 }
2412 phase->set_ctrl_and_loop(replacement, rep_ctrl);
2413 phase->igvn().replace_input_of(replacement, Control, rep_ctrl);
2414
2415 ShenandoahWriteBarrierNode::fix_memory_uses(mem, replacement, rep_proj, rep_ctrl, phase->C->get_alias_index(replacement->adr_type()), phase);
2416 assert(rep_proj->outcnt() != 0, "new proj should have uses");
2417 } else {
2418 if (replacement->in(Memory) != mem) {
2419 phase->igvn()._worklist.push(replacement->in(Memory));
2420 phase->igvn().replace_input_of(replacement, Memory, mem);
2421 }
2422 phase->set_ctrl_and_loop(replacement, rep_ctrl);
2423 phase->igvn().replace_input_of(replacement, Control, rep_ctrl);
2424 }
2425 if (Opcode() == Op_ShenandoahWriteBarrier) {
2426 if (n_proj != NULL) {
2427 phase->lazy_replace(n_proj, in(Memory));
2428 }
2429 }
2430 phase->lazy_replace(this, replacement);
2431 if (rep_proj != NULL) {
2432 phase->set_ctrl_and_loop(rep_proj, rep_ctrl);
2433 }
2434 return replacement;
2435 }
2436 }
2437
2438 return NULL;
2439 }
2440
2441 static void disconnect_barrier_mem(Node* wb, PhaseIterGVN& igvn) {
2442 Node* mem_in = wb->in(ShenandoahBarrierNode::Memory);
2443 Node* proj = wb->find_out_with(Op_ShenandoahWBMemProj);
2444
2445 for (DUIterator_Last imin, i = proj->last_outs(imin); i >= imin; ) {
2446 Node* u = proj->last_out(i);
2447 igvn.rehash_node_delayed(u);
2448 int nb = u->replace_edge(proj, mem_in);
2449 assert(nb > 0, "no replacement?");
2450 i -= nb;
2451 }
2452 }
2453
2454 Node* ShenandoahWriteBarrierNode::move_above_predicates(LoopNode* cl, Node* val_ctrl, PhaseIdealLoop* phase) {
2455 Node* entry = cl->skip_strip_mined()->in(LoopNode::EntryControl);
2456 Node* above_pred = phase->skip_loop_predicates(entry);
2457 Node* ctrl = entry;
2458 while (ctrl != above_pred) {
2459 Node* next = ctrl->in(0);
2460 if (!phase->is_dominator(val_ctrl, next)) {
2461 break;
2462 }
2463 ctrl = next;
2464 }
2465 return ctrl;
2466 }
2467
2468 Node* ShenandoahWriteBarrierNode::try_move_before_loop_helper(LoopNode* cl, Node* val_ctrl, Node* mem, PhaseIdealLoop* phase) {
2469 assert(cl->is_Loop(), "bad control");
2470 Node* ctrl = move_above_predicates(cl, val_ctrl, phase);
2471 Node* mem_ctrl = NULL;
2472 int alias = phase->C->get_alias_index(adr_type());
2473 mem = dom_mem(mem, mem_ctrl, this, ctrl, alias, phase);
2474 if (mem == NULL) {
2475 return NULL;
2476 }
2477
2478 Node* old_mem = in(Memory);
2479 Node* proj = find_out_with(Op_ShenandoahWBMemProj);
2480 if (old_mem != mem && !suitable_mem(mem, old_mem, proj)) {
2481 return NULL;
2482 }
2483
2484 assert(!ShenandoahVerifyOptoBarriers || memory_dominates_all_paths(mem, ctrl, alias, phase), "can't fix the memory graph");
2485 phase->set_ctrl_and_loop(this, ctrl);
2486 phase->igvn().replace_input_of(this, Control, ctrl);
2487 if (old_mem != mem) {
2488 if (proj != NULL) {
2489 disconnect_barrier_mem(this, phase->igvn());
2490 fix_memory_uses(mem, this, proj, ctrl, phase->C->get_alias_index(adr_type()), phase);
2491 assert(proj->outcnt() > 0, "disconnected write barrier");
2492 }
2493 phase->igvn().replace_input_of(this, Memory, mem);
2494 }
2495 if (proj != NULL) {
2496 phase->set_ctrl_and_loop(proj, ctrl);
2497 }
2498 return this;
2499 }
2500
2501 LoopNode* ShenandoahWriteBarrierNode::try_move_before_pre_loop(Node* c, Node* val_ctrl, PhaseIdealLoop* phase) {
2502 // A write barrier between a pre and main loop can get in the way of
2503 // vectorization. Move it above the pre loop if possible
2504 CountedLoopNode* cl = NULL;
2505 if (c->is_IfFalse() &&
2506 c->in(0)->is_CountedLoopEnd()) {
2507 cl = c->in(0)->as_CountedLoopEnd()->loopnode();
2508 } else if (c->is_IfProj() &&
2509 c->in(0)->is_If() &&
2510 c->in(0)->in(0)->is_IfFalse() &&
2511 c->in(0)->in(0)->in(0)->is_CountedLoopEnd()) {
2512 cl = c->in(0)->in(0)->in(0)->as_CountedLoopEnd()->loopnode();
2513 }
2514 if (cl != NULL &&
2515 cl->is_pre_loop() &&
2516 val_ctrl != cl &&
2517 phase->is_dominator(val_ctrl, cl)) {
2518 return cl;
2519 }
2520 return NULL;
2521 }
2522
2523 Node* ShenandoahWriteBarrierNode::try_move_before_loop(Node *n_ctrl, PhaseIdealLoop* phase) {
2524 IdealLoopTree *n_loop = phase->get_loop(n_ctrl);
2525 Node* val = in(ValueIn);
2526 Node* val_ctrl = phase->get_ctrl(val);
2527 if (n_loop != phase->ltree_root() && !n_loop->_irreducible) {
2528 IdealLoopTree *val_loop = phase->get_loop(val_ctrl);
2529 Node* mem = in(Memory);
2530 IdealLoopTree *mem_loop = phase->get_loop(phase->get_ctrl(mem));
2531 if (!n_loop->is_member(val_loop) &&
2532 n_loop->is_member(mem_loop)) {
2533 Node* n_loop_head = n_loop->_head;
2534
2535 if (n_loop_head->is_Loop()) {
2536 LoopNode* loop = n_loop_head->as_Loop();
2537 if (n_loop_head->is_CountedLoop() && n_loop_head->as_CountedLoop()->is_main_loop()) {
2538 LoopNode* res = try_move_before_pre_loop(n_loop_head->in(LoopNode::EntryControl), val_ctrl, phase);
2539 if (res != NULL) {
2540 loop = res;
2541 }
2542 }
2543
2544 return try_move_before_loop_helper(loop, val_ctrl, mem, phase);
2545 }
2546 }
2547 }
2548 LoopNode* ctrl = try_move_before_pre_loop(in(0), val_ctrl, phase);
2549 if (ctrl != NULL) {
2550 return try_move_before_loop_helper(ctrl, val_ctrl, in(Memory), phase);
2551 }
2552 return NULL;
2553 }
2554
2555 void ShenandoahReadBarrierNode::try_move(Node *n_ctrl, PhaseIdealLoop* phase) {
2556 Node* mem = in(MemNode::Memory);
2557 int alias = phase->C->get_alias_index(adr_type());
2558 const bool trace = false;
2559
2560 #ifdef ASSERT
2561 if (trace) { tty->print("Trying to move mem of"); dump(); }
2562 #endif
2563
2564 Node* new_mem = mem;
2565
2566 ResourceMark rm;
2567 VectorSet seen(Thread::current()->resource_area());
2568 Node_List phis;
2569
2570 for (;;) {
2571 #ifdef ASSERT
2572 if (trace) { tty->print("Looking for dominator from"); mem->dump(); }
2573 #endif
2574 if (mem->is_Proj() && mem->in(0)->is_Start()) {
2575 if (new_mem != in(MemNode::Memory)) {
2576 #ifdef ASSERT
2577 if (trace) { tty->print("XXX Setting mem to"); new_mem->dump(); tty->print(" for "); dump(); }
2578 #endif
2579 phase->igvn().replace_input_of(this, MemNode::Memory, new_mem);
2580 }
2581 return;
2582 }
2583
2584 Node* candidate = mem;
2585 do {
2586 if (!is_independent(mem)) {
2587 if (trace) { tty->print_cr("Not independent"); }
2588 if (new_mem != in(MemNode::Memory)) {
2589 #ifdef ASSERT
2590 if (trace) { tty->print("XXX Setting mem to"); new_mem->dump(); tty->print(" for "); dump(); }
2591 #endif
2592 phase->igvn().replace_input_of(this, MemNode::Memory, new_mem);
2593 }
2594 return;
2595 }
2596 if (seen.test_set(mem->_idx)) {
2597 if (trace) { tty->print_cr("Already seen"); }
2598 ShouldNotReachHere();
2599 // Strange graph
2600 if (new_mem != in(MemNode::Memory)) {
2601 #ifdef ASSERT
2602 if (trace) { tty->print("XXX Setting mem to"); new_mem->dump(); tty->print(" for "); dump(); }
2603 #endif
2604 phase->igvn().replace_input_of(this, MemNode::Memory, new_mem);
2605 }
2606 return;
2607 }
2608 if (mem->is_Phi()) {
2609 phis.push(mem);
2610 }
2611 mem = next_mem(mem, alias);
2612 if (mem->bottom_type() == Type::MEMORY) {
2613 candidate = mem;
2614 }
2615 assert(is_dominator(phase->ctrl_or_self(mem), n_ctrl, mem, this, phase) == phase->is_dominator(phase->ctrl_or_self(mem), n_ctrl), "strange dominator");
2616 #ifdef ASSERT
2617 if (trace) { tty->print("Next mem is"); mem->dump(); }
2618 #endif
2619 } while (mem->bottom_type() != Type::MEMORY || !phase->is_dominator(phase->ctrl_or_self(mem), n_ctrl));
2620
2621 assert(mem->bottom_type() == Type::MEMORY, "bad mem");
2622
2623 bool not_dom = false;
2624 for (uint i = 0; i < phis.size() && !not_dom; i++) {
2625 Node* nn = phis.at(i);
2626
2627 #ifdef ASSERT
2628 if (trace) { tty->print("Looking from phi"); nn->dump(); }
2629 #endif
2630 assert(nn->is_Phi(), "phis only");
2631 for (uint j = 2; j < nn->req() && !not_dom; j++) {
2632 Node* m = nn->in(j);
2633 #ifdef ASSERT
2634 if (trace) { tty->print("Input %d is", j); m->dump(); }
2635 #endif
2636 while (m != mem && !seen.test_set(m->_idx)) {
2637 if (is_dominator(phase->ctrl_or_self(m), phase->ctrl_or_self(mem), m, mem, phase)) {
2638 not_dom = true;
2639 // Scheduling anomaly
2640 #ifdef ASSERT
2641 if (trace) { tty->print("Giving up"); m->dump(); }
2642 #endif
2643 break;
2644 }
2645 if (!is_independent(m)) {
2646 if (trace) { tty->print_cr("Not independent"); }
2647 if (new_mem != in(MemNode::Memory)) {
2648 #ifdef ASSERT
2649 if (trace) { tty->print("XXX Setting mem to"); new_mem->dump(); tty->print(" for "); dump(); }
2650 #endif
2651 phase->igvn().replace_input_of(this, MemNode::Memory, new_mem);
2652 }
2653 return;
2654 }
2655 if (m->is_Phi()) {
2656 phis.push(m);
2657 }
2658 m = next_mem(m, alias);
2659 #ifdef ASSERT
2660 if (trace) { tty->print("Next mem is"); m->dump(); }
2661 #endif
2662 }
2663 }
2664 }
2665 if (!not_dom) {
2666 new_mem = mem;
2667 phis.clear();
2668 } else {
2669 seen.Clear();
2670 }
2671 }
2672 }
2673
2674 CallStaticJavaNode* ShenandoahWriteBarrierNode::pin_and_expand_null_check(PhaseIterGVN& igvn) {
2675 Node* val = in(ValueIn);
2676
2677 #ifdef ASSERT
2678 const Type* val_t = igvn.type(val);
2679 assert(val_t->meet(TypePtr::NULL_PTR) != val_t, "should be not null");
2680 #endif
2681
2682 if (val->Opcode() == Op_CastPP &&
2683 val->in(0)->Opcode() == Op_IfTrue &&
2684 val->in(0)->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none) &&
2685 val->in(0)->in(0)->is_If() &&
2686 val->in(0)->in(0)->in(1)->Opcode() == Op_Bool &&
2687 val->in(0)->in(0)->in(1)->as_Bool()->_test._test == BoolTest::ne &&
2688 val->in(0)->in(0)->in(1)->in(1)->Opcode() == Op_CmpP &&
2689 val->in(0)->in(0)->in(1)->in(1)->in(1) == val->in(1) &&
2690 val->in(0)->in(0)->in(1)->in(1)->in(2)->bottom_type() == TypePtr::NULL_PTR) {
2691 assert(val->in(0)->in(0)->in(1)->in(1)->in(1) == val->in(1), "");
2692 CallStaticJavaNode* unc = val->in(0)->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none);
2693 return unc;
2694 }
2695 return NULL;
2696 }
2697
2698 void ShenandoahWriteBarrierNode::pin_and_expand_move_barrier(PhaseIdealLoop* phase) {
2699 Node* unc = pin_and_expand_null_check(phase->igvn());
2700 Node* val = in(ValueIn);
2701
2702 if (unc != NULL) {
2703 Node* ctrl = phase->get_ctrl(this);
2704 Node* unc_ctrl = val->in(0);
2705
2706 // Don't move write barrier in a loop
2707 IdealLoopTree* loop = phase->get_loop(ctrl);
2708 IdealLoopTree* unc_loop = phase->get_loop(unc_ctrl);
2709
2710 if (!unc_loop->is_member(loop)) {
2711 return;
2712 }
2713
2714 Node* branch = no_branches(ctrl, unc_ctrl, false, phase);
2715 assert(branch == NULL || branch == NodeSentinel, "was not looking for a branch");
2716 if (branch == NodeSentinel) {
2717 return;
2718 }
2719
2720 Node* mem = in(Memory);
2721 Node* old_mem = mem;
2722
2723 Node* mem_ctrl = NULL;
2724 int alias = phase->C->get_alias_index(adr_type());
2725 mem = dom_mem(mem, mem_ctrl, this, unc_ctrl, alias, phase);
2726 if (mem == NULL) {
2727 return;
2728 }
2729
2730 Node* proj = find_out_with(Op_ShenandoahWBMemProj);
2731 if (mem != old_mem && !fix_mem_phis(mem, mem_ctrl, unc_ctrl, alias, phase)) {
2732 return;
2733 }
2734
2735 assert(mem == old_mem || memory_dominates_all_paths(mem, unc_ctrl, alias, phase), "can't fix the memory graph");
2736 phase->set_ctrl_and_loop(this, unc_ctrl);
2737 if (in(Control) != NULL) {
2738 phase->igvn().replace_input_of(this, Control, unc_ctrl);
2739 }
2740 disconnect_barrier_mem(this, phase->igvn());
2741 fix_memory_uses(mem, this, proj, unc_ctrl, phase->C->get_alias_index(adr_type()), phase);
2742 assert(proj->outcnt() > 0, "disconnected write barrier");
2743 phase->igvn().replace_input_of(this, Memory, mem);
2744 phase->set_ctrl_and_loop(proj, unc_ctrl);
2745 }
2746 }
2747
2748 void ShenandoahWriteBarrierNode::pin_and_expand_helper(PhaseIdealLoop* phase) {
2749 Node* val = in(ValueIn);
2750 Node* ctrl = phase->get_ctrl(this);
2751 // Replace all uses of barrier's input that are dominated by ctrl
2752 // with the value returned by the barrier: no need to keep both
2753 // live.
2754 for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) {
2755 Node* u = val->fast_out(i);
2756 if (u != this) {
2757 if (u->is_Phi()) {
2758 int nb = 0;
2759 for (uint j = 1; j < u->req(); j++) {
2760 if (u->in(j) == val) {
2761 Node* c = u->in(0)->in(j);
2762 if (phase->is_dominator(ctrl, c)) {
2763 phase->igvn().replace_input_of(u, j, this);
2764 nb++;
2765 }
2766 }
2767 }
2768 if (nb > 0) {
2769 imax -= nb;
2770 --i;
2771 }
2772 } else {
2773 Node* c = phase->ctrl_or_self(u);
2774 if (is_dominator(ctrl, c, this, u, phase)) {
2775 phase->igvn().rehash_node_delayed(u);
2776 int nb = u->replace_edge(val, this);
2777 assert(nb > 0, "no update?");
2778 --i, imax -= nb;
2779 }
2780 }
2781 }
2782 }
2783 }
2784
2785 Node* ShenandoahWriteBarrierNode::pick_phi(Node* phi1, Node* phi2, Node_Stack& phis, VectorSet& visited, PhaseIdealLoop* phase) {
2786 assert(phis.size() == 0, "stack needs to be empty");
2787 uint i = 1;
2788 int phi_dominates = -1;
2789 for (;;) {
2790 assert(phi1->req() == phi2->req(), "strange pair of phis");
2791 assert(phis.size() % 2 == 0, "");
2792 Node* in1 = phi1->in(i);
2793 Node* in2 = phi2->in(i);
2794
2795 if (in1->is_MergeMem()) {
2796 in1 = in1->as_MergeMem()->base_memory();
2797 }
2798 if (in2->is_MergeMem()) {
2799 in2 = in2->as_MergeMem()->base_memory();
2800 }
2801
2802 if (in1 == in2) {
2803 //continue
2804 } else if (in1->is_Phi() && in2->is_Phi() && in1->in(0) == in2->in(0)) {
2805 assert(!visited.test_set(in1->_idx), "no loop");
2806 assert(!visited.test_set(in2->_idx), "no loop");
2807 phis.push(phi1, i+1);
2808 phis.push(phi2, i+1);
2809 phi1 = in1;
2810 phi2 = in2;
2811 i = 1;
2812 } else {
2813 Node* in1_c = phase->get_ctrl(in1);
2814 Node* in2_c = phase->get_ctrl(in2);
2815 if (is_dominator(in1_c, in2_c, in1, in2, phase)) {
2816 assert(!is_dominator(in2_c, in1_c, in2, in1, phase), "one has to dominate the other");
2817 assert(phi_dominates == -1 || phi_dominates == 1, "all inputs must dominate");
2818 phi_dominates = 1;
2819 } else {
2820 assert(is_dominator(in2_c, in1_c, in2, in1, phase), "one must dominate the other");
2821 assert(!is_dominator(in1_c, in2_c, in1, in2, phase), "one has to dominate the other");
2822 assert(phi_dominates == -1 || phi_dominates == 2, "all inputs must dominate");
2823 phi_dominates = 2;
2824 }
2825 }
2826 i++;
2827
2828 while (i >= phi1->req() && phis.size() > 0) {
2829 i = phis.index();
2830 phi2 = phis.node();
2831 phis.pop();
2832 phi1 = phis.node();
2833 phis.pop();
2834 }
2835
2836 if (i >= phi1->req() && phis.size() == 0) {
2837 Node* phi = NULL;
2838 if (phi_dominates == 1) {
2839 return phi2;
2840 } else if (phi_dominates == 2) {
2841 return phi1;
2842 } else {
2843 return phi1;
2844 }
2845 }
2846 }
2847 return NULL;
2848 }
2849
2850 bool ShenandoahWriteBarrierNode::mem_is_valid(Node* m, Node* c, PhaseIdealLoop* phase) {
2851 return m != NULL && get_ctrl(m, phase) == c;
2852 }
2853
2854 Node* ShenandoahWriteBarrierNode::find_raw_mem(Node* ctrl, Node* n, const Node_List& memory_nodes, PhaseIdealLoop* phase) {
2855 assert(n == NULL || phase->ctrl_or_self(n) == ctrl, "");
2856 Node* raw_mem = memory_nodes[ctrl->_idx];
2857 Node* c = ctrl;
2858 while (!mem_is_valid(raw_mem, c, phase) &&
2859 (!c->is_CatchProj() || raw_mem == NULL || c->in(0)->in(0)->in(0) != get_ctrl(raw_mem, phase))) {
2860 c = phase->idom(c);
2861 raw_mem = memory_nodes[c->_idx];
2862 }
2863 if (n != NULL && mem_is_valid(raw_mem, c, phase)) {
2864 while (!is_dominator_same_ctrl(c, raw_mem, n, phase) && phase->ctrl_or_self(raw_mem) == ctrl) {
2865 raw_mem = next_mem(raw_mem, Compile::AliasIdxRaw);
2866 }
2867 if (raw_mem->is_MergeMem()) {
2868 raw_mem = raw_mem->as_MergeMem()->memory_at(Compile::AliasIdxRaw);
2869 }
2870 if (!mem_is_valid(raw_mem, c, phase)) {
2871 do {
2872 c = phase->idom(c);
2873 raw_mem = memory_nodes[c->_idx];
2874 } while (!mem_is_valid(raw_mem, c, phase) &&
2875 (!c->is_CatchProj() || raw_mem == NULL || c->in(0)->in(0)->in(0) != get_ctrl(raw_mem, phase)));
2876 }
2877 }
2878 assert(raw_mem->bottom_type() == Type::MEMORY, "");
2879 return raw_mem;
2880 }
2881
2882 Node* ShenandoahWriteBarrierNode::find_bottom_mem(Node* ctrl, PhaseIdealLoop* phase) {
2883 Node* mem = NULL;
2884 Node* c = ctrl;
2885 do {
2886 if (c->is_Region()) {
2887 Node* phi_bottom = NULL;
2888 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
2889 Node* u = c->fast_out(i);
2890 if (u->is_Phi() && u->bottom_type() == Type::MEMORY) {
2891 if (u->adr_type() == TypePtr::BOTTOM) {
2892 if (phi_bottom != NULL) {
2893 phi_bottom = NodeSentinel;
2894 } else {
2895 phi_bottom = u;
2896 }
2897 }
2898 }
2899 }
2900 if (phi_bottom != NULL) {
2901 if (phi_bottom != NodeSentinel) {
2902 mem = phi_bottom;
2903 } else {
2904 Node* phi = NULL;
2905 ResourceMark rm;
2906 Node_Stack phis(0);
2907 VectorSet visited(Thread::current()->resource_area());
2908 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
2909 Node* u = c->fast_out(i);
2910 if (u->is_Phi() && u->bottom_type() == Type::MEMORY && u->adr_type() == TypePtr::BOTTOM) {
2911 if (phi == NULL) {
2912 phi = u;
2913 } else {
2914 phi = pick_phi(phi, u, phis, visited, phase);
2915 }
2916 }
2917 }
2918 mem = phi;
2919 }
2920 }
2921 } else {
2922 if (c->is_Call() && c->as_Call()->_entry_point != OptoRuntime::rethrow_stub()) {
2923 CallProjections projs;
2924 c->as_Call()->extract_projections(&projs, true, false);
2925 if (projs.fallthrough_memproj != NULL) {
2926 if (projs.fallthrough_memproj->adr_type() == TypePtr::BOTTOM) {
2927 if (projs.catchall_memproj == NULL) {
2928 mem = projs.fallthrough_memproj;
2929 } else {
2930 if (phase->is_dominator(projs.fallthrough_catchproj, ctrl)) {
2931 mem = projs.fallthrough_memproj;
2932 } else {
2933 assert(phase->is_dominator(projs.catchall_catchproj, ctrl), "one proj must dominate barrier");
2934 mem = projs.catchall_memproj;
2935 }
2936 }
2937 }
2938 } else {
2939 Node* proj = c->as_Call()->proj_out(TypeFunc::Memory);
2940 if (proj != NULL &&
2941 proj->adr_type() == TypePtr::BOTTOM) {
2942 mem = proj;
2943 }
2944 }
2945 } else {
2946 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
2947 Node* u = c->fast_out(i);
2948 if (u->is_Proj() &&
2949 u->bottom_type() == Type::MEMORY &&
2950 u->adr_type() == TypePtr::BOTTOM) {
2951 assert(c->is_SafePoint() || c->is_MemBar() || c->is_Start(), "");
2952 assert(mem == NULL, "only one proj");
2953 mem = u;
2954 }
2955 }
2956 }
2957 }
2958 c = phase->idom(c);
2959 } while (mem == NULL);
2960 return mem;
2961 }
2962
2963 void ShenandoahWriteBarrierNode::follow_barrier_uses(Node* n, Node* ctrl, Unique_Node_List& uses, PhaseIdealLoop* phase) {
2964 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2965 Node* u = n->fast_out(i);
2966 if (!u->is_CFG() && phase->get_ctrl(u) == ctrl && (!u->is_Phi() || !u->in(0)->is_Loop() || u->in(LoopNode::LoopBackControl) != n)) {
2967 uses.push(u);
2968 }
2969 }
2970 }
2971
2972 Node* ShenandoahWriteBarrierNode::get_ctrl(Node* n, PhaseIdealLoop* phase) {
2973 Node* c = phase->get_ctrl(n);
2974 if (n->is_Proj() && n->in(0)->is_Call()) {
2975 assert(c == n->in(0), "");
2976 CallNode* call = c->as_Call();
2977 CallProjections projs;
2978 call->extract_projections(&projs, true, false);
2979 if (projs.catchall_memproj != NULL) {
2980 if (projs.fallthrough_memproj == n) {
2981 c = projs.fallthrough_catchproj;
2982 } else {
2983 assert(projs.catchall_memproj == n, "");
2984 c = projs.catchall_catchproj;
2985 }
2986 }
2987 }
2988 return c;
2989 }
2990
2991 Node* ShenandoahWriteBarrierNode::ctrl_or_self(Node* n, PhaseIdealLoop* phase) {
2992 if (phase->has_ctrl(n))
2993 return get_ctrl(n, phase);
2994 else {
2995 assert (n->is_CFG(), "must be a CFG node");
2996 return n;
2997 }
2998 }
2999
3000 #ifdef ASSERT
3001 static bool has_never_branch(Node* root) {
3002 for (uint i = 1; i < root->req(); i++) {
3003 Node* in = root->in(i);
3004 if (in != NULL && in->Opcode() == Op_Halt && in->in(0)->is_Proj() && in->in(0)->in(0)->Opcode() == Op_NeverBranch) {
3005 return true;
3006 }
3007 }
3008 return false;
3009 }
3010 #endif
3011
3012 void ShenandoahWriteBarrierNode::collect_memory_nodes(int alias, Node_List& memory_nodes, PhaseIdealLoop* phase) {
3013 Node_Stack stack(0);
3014 VectorSet visited(Thread::current()->resource_area());
3015 Node_List regions;
3016
3017 // Walk the raw memory graph and create a mapping from CFG node to
3018 // memory node. Exclude phis for now.
3019 stack.push(phase->C->root(), 1);
3020 do {
3021 Node* n = stack.node();
3022 int opc = n->Opcode();
3023 uint i = stack.index();
3024 if (i < n->req()) {
3025 Node* mem = NULL;
3026 if (opc == Op_Root) {
3027 Node* in = n->in(i);
3028 int in_opc = in->Opcode();
3029 if (in_opc == Op_Return || in_opc == Op_Rethrow) {
3030 mem = in->in(TypeFunc::Memory);
3031 } else if (in_opc == Op_Halt) {
3032 if (in->in(0)->is_Region()) {
3033 #ifdef ASSERT
3034 Node* r = in->in(0);
3035 for (uint j = 1; j < r->req(); j++) {
3036 assert(r->in(j)->is_Proj() && r->in(j)->in(0)->Opcode() == Op_NeverBranch, "");
3037 }
3038 #endif
3039 } else {
3040 Node* proj = in->in(0);
3041 assert(proj->is_Proj(), "");
3042 Node* in = proj->in(0);
3043 assert(in->is_CallStaticJava() || in->Opcode() == Op_NeverBranch || in->Opcode() == Op_Catch, "");
3044 if (in->is_CallStaticJava()) {
3045 mem = in->in(TypeFunc::Memory);
3046 } else if (in->Opcode() == Op_Catch) {
3047 Node* call = in->in(0)->in(0);
3048 assert(call->is_Call(), "");
3049 mem = call->in(TypeFunc::Memory);
3050 }
3051 }
3052 } else {
3053 #ifdef ASSERT
3054 n->dump();
3055 in->dump();
3056 #endif
3057 ShouldNotReachHere();
3058 }
3059 } else {
3060 assert(n->is_Phi() && n->bottom_type() == Type::MEMORY, "");
3061 assert(n->adr_type() == TypePtr::BOTTOM || phase->C->get_alias_index(n->adr_type()) == alias, "");
3062 mem = n->in(i);
3063 }
3064 i++;
3065 stack.set_index(i);
3066 if (mem == NULL) {
3067 continue;
3068 }
3069 for (;;) {
3070 if (visited.test_set(mem->_idx) || mem->is_Start()) {
3071 break;
3072 }
3073 if (mem->is_Phi()) {
3074 stack.push(mem, 2);
3075 mem = mem->in(1);
3076 } else if (mem->is_Proj()) {
3077 stack.push(mem, mem->req());
3078 mem = mem->in(0);
3079 } else if (mem->is_SafePoint() || mem->is_MemBar()) {
3080 mem = mem->in(TypeFunc::Memory);
3081 } else if (mem->is_MergeMem()) {
3082 mem = mem->as_MergeMem()->memory_at(alias);
3083 } else if (mem->is_Store() || mem->is_LoadStore() || mem->is_ClearArray()) {
3084 stack.push(mem, mem->req());
3085 mem = mem->in(MemNode::Memory);
3086 } else {
3087 #ifdef ASSERT
3088 mem->dump();
3089 #endif
3090 ShouldNotReachHere();
3091 }
3092 }
3093 } else {
3094 if (n->is_Phi()) {
3095 // Nothing
3096 } else if (!n->is_Root()) {
3097 Node* c = get_ctrl(n, phase);
3098 memory_nodes.map(c->_idx, n);
3099 }
3100 stack.pop();
3101 }
3102 } while(stack.is_nonempty());
3103
3104 // Iterate over CFG nodes in rpo and propagate memory state to
3105 // compute memory state at regions, creating new phis if needed.
3106 Node_List rpo_list;
3107 visited.Clear();
3108 phase->rpo(phase->C->root(), stack, visited, rpo_list);
3109 Node* root = rpo_list.pop();
3110 assert(root == phase->C->root(), "");
3111
3112 const bool trace = false;
3113 #ifdef ASSERT
3114 if (trace) {
3115 for (int i = rpo_list.size() - 1; i >= 0; i--) {
3116 Node* c = rpo_list.at(i);
3117 if (memory_nodes[c->_idx] != NULL) {
3118 tty->print("X %d", c->_idx); memory_nodes[c->_idx]->dump();
3119 }
3120 }
3121 }
3122 #endif
3123 uint last = phase->C->unique();
3124
3125 #ifdef ASSERT
3126 uint8_t max_depth = 0;
3127 for (LoopTreeIterator iter(phase->ltree_root()); !iter.done(); iter.next()) {
3128 IdealLoopTree* lpt = iter.current();
3129 max_depth = MAX2(max_depth, lpt->_nest);
3130 }
3131 #endif
3132
3133 bool progress = true;
3134 int iteration = 0;
3135 Node_List dead_phis;
3136 while (progress) {
3137 progress = false;
3138 iteration++;
3139 assert(iteration <= 2+max_depth || phase->C->has_irreducible_loop(), "");
3140 if (trace) { tty->print_cr("XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"); }
3141 IdealLoopTree* last_updated_ilt = NULL;
3142 for (int i = rpo_list.size() - 1; i >= 0; i--) {
3143 Node* c = rpo_list.at(i);
3144
3145 Node* prev_mem = memory_nodes[c->_idx];
3146 if (c->is_Region()) {
3147 Node* prev_region = regions[c->_idx];
3148 Node* unique = NULL;
3149 for (uint j = 1; j < c->req() && unique != NodeSentinel; j++) {
3150 Node* m = memory_nodes[c->in(j)->_idx];
3151 assert(m != NULL || (c->is_Loop() && j == LoopNode::LoopBackControl && iteration == 1) || phase->C->has_irreducible_loop() || has_never_branch(phase->C->root()), "expect memory state");
3152 if (m != NULL) {
3153 if (m == prev_region && ((c->is_Loop() && j == LoopNode::LoopBackControl) || (prev_region->is_Phi() && prev_region->in(0) == c))) {
3154 assert(c->is_Loop() && j == LoopNode::LoopBackControl || phase->C->has_irreducible_loop(), "");
3155 // continue
3156 } else if (unique == NULL) {
3157 unique = m;
3158 } else if (m == unique) {
3159 // continue
3160 } else {
3161 unique = NodeSentinel;
3162 }
3163 }
3164 }
3165 assert(unique != NULL, "empty phi???");
3166 if (unique != NodeSentinel) {
3167 if (prev_region != NULL && prev_region->is_Phi() && prev_region->in(0) == c) {
3168 dead_phis.push(prev_region);
3169 }
3170 regions.map(c->_idx, unique);
3171 } else {
3172 Node* phi = NULL;
3173 if (prev_region != NULL && prev_region->is_Phi() && prev_region->in(0) == c && prev_region->_idx >= last) {
3174 phi = prev_region;
3175 for (uint k = 1; k < c->req(); k++) {
3176 Node* m = memory_nodes[c->in(k)->_idx];
3177 assert(m != NULL, "expect memory state");
3178 phi->set_req(k, m);
3179 }
3180 } else {
3181 for (DUIterator_Fast jmax, j = c->fast_outs(jmax); j < jmax && phi == NULL; j++) {
3182 Node* u = c->fast_out(j);
3183 if (u->is_Phi() && u->bottom_type() == Type::MEMORY &&
3184 (u->adr_type() == TypePtr::BOTTOM || phase->C->get_alias_index(u->adr_type()) == alias)) {
3185 phi = u;
3186 for (uint k = 1; k < c->req() && phi != NULL; k++) {
3187 Node* m = memory_nodes[c->in(k)->_idx];
3188 assert(m != NULL, "expect memory state");
3189 if (u->in(k) != m) {
3190 phi = NULL;
3191 }
3192 }
3193 }
3194 }
3195 if (phi == NULL) {
3196 phi = new PhiNode(c, Type::MEMORY, phase->C->get_adr_type(alias));
3197 for (uint k = 1; k < c->req(); k++) {
3198 Node* m = memory_nodes[c->in(k)->_idx];
3199 assert(m != NULL, "expect memory state");
3200 phi->init_req(k, m);
3201 }
3202 }
3203 }
3204 assert(phi != NULL, "");
3205 regions.map(c->_idx, phi);
3206 }
3207 Node* current_region = regions[c->_idx];
3208 if (current_region != prev_region) {
3209 progress = true;
3210 if (prev_region == prev_mem) {
3211 memory_nodes.map(c->_idx, current_region);
3212 }
3213 }
3214 } else if (prev_mem == NULL || prev_mem->is_Phi() || ctrl_or_self(prev_mem, phase) != c) {
3215 Node* m = memory_nodes[phase->idom(c)->_idx];
3216 assert(m != NULL, "expect memory state");
3217 if (m != prev_mem) {
3218 memory_nodes.map(c->_idx, m);
3219 progress = true;
3220 }
3221 }
3222 #ifdef ASSERT
3223 if (trace) { tty->print("X %d", c->_idx); memory_nodes[c->_idx]->dump(); }
3224 #endif
3225 }
3226 }
3227
3228 // Replace existing phi with computed memory state for that region
3229 // if different (could be a new phi or a dominating memory node if
3230 // that phi was found to be useless).
3231 while (dead_phis.size() > 0) {
3232 Node* n = dead_phis.pop();
3233 n->replace_by(phase->C->top());
3234 n->destruct();
3235 }
3236 for (int i = rpo_list.size() - 1; i >= 0; i--) {
3237 Node* c = rpo_list.at(i);
3238 if (c->is_Region()) {
3239 Node* n = regions[c->_idx];
3240 if (n->is_Phi() && n->_idx >= last && n->in(0) == c) {
3241 phase->register_new_node(n, c);
3242 }
3243 }
3244 }
3245 for (int i = rpo_list.size() - 1; i >= 0; i--) {
3246 Node* c = rpo_list.at(i);
3247 if (c->is_Region()) {
3248 Node* n = regions[c->_idx];
3249 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
3250 Node* u = c->fast_out(i);
3251 if (u->is_Phi() && u->bottom_type() == Type::MEMORY &&
3252 u != n) {
3253 if (u->adr_type() == TypePtr::BOTTOM) {
3254 fix_memory_uses(u, n, n, c, alias, phase);
3255 } else if (phase->C->get_alias_index(u->adr_type()) == alias) {
3256 phase->lazy_replace(u, n);
3257 --i; --imax;
3258 }
3259 }
3260 }
3261 }
3262 }
3263 }
3264
3265 void ShenandoahWriteBarrierNode::fix_raw_mem(Node* ctrl, Node* region, Node* raw_mem, Node* raw_mem_for_ctrl, Node* raw_mem_phi,
3266 Node_List& memory_nodes, Unique_Node_List& uses, PhaseIdealLoop* phase) {
3267 const bool trace = false;
3268 DEBUG_ONLY(if (trace) { tty->print("ZZZ control is"); ctrl->dump(); });
3269 DEBUG_ONLY(if (trace) { tty->print("ZZZ mem is"); raw_mem->dump(); });
3270 GrowableArray<Node*> phis;
3271 if (raw_mem_for_ctrl != raw_mem) {
3272 Node* old = raw_mem_for_ctrl;
3273 Node* prev = NULL;
3274 while (old != raw_mem) {
3275 assert(old->is_Store() || old->is_LoadStore() || old->is_ClearArray(), "");
3276 prev = old;
3277 old = old->in(MemNode::Memory);
3278 }
3279 assert(prev != NULL, "");
3280 memory_nodes.map(ctrl->_idx, raw_mem);
3281 memory_nodes.map(region->_idx, raw_mem_for_ctrl);
3282 phase->igvn().replace_input_of(prev, MemNode::Memory, raw_mem_phi);
3283 } else {
3284 memory_nodes.map(region->_idx, raw_mem_phi);
3285 uses.clear();
3286 uses.push(region);
3287 for(uint next = 0; next < uses.size(); next++ ) {
3288 Node *n = uses.at(next);
3289 assert(n->is_CFG(), "");
3290 DEBUG_ONLY(if (trace) { tty->print("ZZZ ctrl"); n->dump(); });
3291 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
3292 Node* u = n->fast_out(i);
3293 if (!u->is_Root() && u->is_CFG() && u != n) {
3294 Node* m = memory_nodes[u->_idx];
3295 if (u->is_Region() && !has_mem_phi(phase->C, u, Compile::AliasIdxRaw)) {
3296 DEBUG_ONLY(if (trace) { tty->print("ZZZ region"); u->dump(); });
3297 DEBUG_ONLY(if (trace && m != NULL) { tty->print("ZZZ mem"); m->dump(); });
3298
3299 if (!mem_is_valid(m, u, phase) || !m->is_Phi()) {
3300 bool push = true;
3301 bool create_phi = true;
3302 if (phase->is_dominator(region, u)) {
3303 create_phi = false;
3304 } else if (!phase->C->has_irreducible_loop()) {
3305 IdealLoopTree* loop = phase->get_loop(ctrl);
3306 bool do_check = true;
3307 IdealLoopTree* l = loop;
3308 create_phi = false;
3309 while (l != phase->ltree_root()) {
3310 if (phase->is_dominator(l->_head, u) && phase->is_dominator(phase->idom(u), l->_head)) {
3311 create_phi = true;
3312 do_check = false;
3313 break;
3314 }
3315 l = l->_parent;
3316 }
3317
3318 if (do_check) {
3319 assert(!create_phi, "");
3320 IdealLoopTree* u_loop = phase->get_loop(u);
3321 if (u_loop != phase->ltree_root() && u_loop->is_member(loop)) {
3322 Node* c = ctrl;
3323 while (!phase->is_dominator(c, u_loop->tail())) {
3324 c = phase->idom(c);
3325 }
3326 if (!phase->is_dominator(c, u)) {
3327 do_check = false;
3328 }
3329 }
3330 }
3331
3332 if (do_check && phase->is_dominator(phase->idom(u), region)) {
3333 create_phi = true;
3334 }
3335 }
3336 if (create_phi) {
3337 Node* phi = new PhiNode(u, Type::MEMORY, TypeRawPtr::BOTTOM);
3338 phase->register_new_node(phi, u);
3339 phis.push(phi);
3340 DEBUG_ONLY(if (trace) { tty->print("ZZZ new phi"); phi->dump(); });
3341 if (!mem_is_valid(m, u, phase)) {
3342 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting mem"); phi->dump(); });
3343 memory_nodes.map(u->_idx, phi);
3344 } else {
3345 DEBUG_ONLY(if (trace) { tty->print("ZZZ NOT setting mem"); m->dump(); });
3346 for (;;) {
3347 assert(m->is_Mem() || m->is_LoadStore() || m->is_Proj() /*|| m->is_MergeMem()*/, "");
3348 Node* next = NULL;
3349 if (m->is_Proj()) {
3350 next = m->in(0);
3351 } else {
3352 next = m->in(MemNode::Memory);
3353 }
3354 if (phase->get_ctrl(next) != u) {
3355 break;
3356 }
3357 if (next->is_MergeMem()) {
3358 assert(phase->get_ctrl(next->as_MergeMem()->memory_at(Compile::AliasIdxRaw)) != u, "");
3359 break;
3360 }
3361 if (next->is_Phi()) {
3362 assert(next->adr_type() == TypePtr::BOTTOM && next->in(0) == u, "");
3363 break;
3364 }
3365 m = next;
3366 }
3367
3368 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting to phi"); m->dump(); });
3369 assert(m->is_Mem() || m->is_LoadStore(), "");
3370 phase->igvn().replace_input_of(m, MemNode::Memory, phi);
3371 push = false;
3372 }
3373 } else {
3374 DEBUG_ONLY(if (trace) { tty->print("ZZZ skipping region"); u->dump(); });
3375 }
3376 if (push) {
3377 uses.push(u);
3378 }
3379 }
3380 } else if (!mem_is_valid(m, u, phase)) {
3381 uses.push(u);
3382 }
3383 }
3384 }
3385 }
3386 for (int i = 0; i < phis.length(); i++) {
3387 Node* n = phis.at(i);
3388 Node* r = n->in(0);
3389 DEBUG_ONLY(if (trace) { tty->print("ZZZ fixing new phi"); n->dump(); });
3390 for (uint j = 1; j < n->req(); j++) {
3391 Node* m = find_raw_mem(r->in(j), NULL, memory_nodes, phase);
3392 phase->igvn().replace_input_of(n, j, m);
3393 DEBUG_ONLY(if (trace) { tty->print("ZZZ fixing new phi: %d", j); m->dump(); });
3394 }
3395 }
3396 }
3397 uint last = phase->C->unique();
3398 MergeMemNode* mm = NULL;
3399 int alias = Compile::AliasIdxRaw;
3400 DEBUG_ONLY(if (trace) { tty->print("ZZZ raw mem is"); raw_mem->dump(); });
3401 for (DUIterator i = raw_mem->outs(); raw_mem->has_out(i); i++) {
3402 Node* u = raw_mem->out(i);
3403 if (u->_idx < last) {
3404 if (u->is_Mem()) {
3405 if (phase->C->get_alias_index(u->adr_type()) == alias) {
3406 Node* m = find_raw_mem(phase->get_ctrl(u), u, memory_nodes, phase);
3407 if (m != raw_mem) {
3408 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
3409 phase->igvn().replace_input_of(u, MemNode::Memory, m);
3410 --i;
3411 }
3412 }
3413 } else if (u->is_MergeMem()) {
3414 MergeMemNode* u_mm = u->as_MergeMem();
3415 if (u_mm->memory_at(alias) == raw_mem) {
3416 MergeMemNode* newmm = NULL;
3417 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
3418 Node* uu = u->fast_out(j);
3419 assert(!uu->is_MergeMem(), "chain of MergeMems?");
3420 if (uu->is_Phi()) {
3421 assert(uu->adr_type() == TypePtr::BOTTOM, "");
3422 Node* region = uu->in(0);
3423 int nb = 0;
3424 for (uint k = 1; k < uu->req(); k++) {
3425 if (uu->in(k) == u) {
3426 Node* m = find_raw_mem(region->in(k), NULL, memory_nodes, phase);
3427 if (m != raw_mem) {
3428 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of phi %d", k); uu->dump(); });
3429 if (newmm == NULL || 1) {
3430 newmm = clone_merge_mem(u, raw_mem, alias, m, phase->ctrl_or_self(m), i, phase);
3431 }
3432 if (newmm != u) {
3433 phase->igvn().replace_input_of(uu, k, newmm);
3434 nb++;
3435 --jmax;
3436 }
3437 }
3438 }
3439 }
3440 if (nb > 0) {
3441 --j;
3442 }
3443 } else {
3444 Node* m = find_raw_mem(phase->ctrl_or_self(uu), uu, memory_nodes, phase);
3445 if (m != raw_mem) {
3446 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); uu->dump(); });
3447 if (newmm == NULL || 1) {
3448 newmm = clone_merge_mem(u, raw_mem, alias, m, phase->ctrl_or_self(m), i, phase);
3449 }
3450 if (newmm != u) {
3451 phase->igvn().replace_input_of(uu, uu->find_edge(u), newmm);
3452 --j, --jmax;
3453 }
3454 }
3455 }
3456 }
3457 }
3458 } else if (u->is_Phi()) {
3459 assert(u->bottom_type() == Type::MEMORY, "what else?");
3460 if (u->adr_type() == TypeRawPtr::BOTTOM || u->adr_type() == TypePtr::BOTTOM) {
3461 Node* region = u->in(0);
3462 bool replaced = false;
3463 for (uint j = 1; j < u->req(); j++) {
3464 if (u->in(j) == raw_mem) {
3465 Node* m = find_raw_mem(region->in(j), NULL, memory_nodes, phase);
3466 Node* nnew = m;
3467 if (m != raw_mem) {
3468 if (u->adr_type() == TypePtr::BOTTOM) {
3469 if (mm == NULL || 1) {
3470 mm = allocate_merge_mem(raw_mem, alias, m, phase->ctrl_or_self(m), phase);
3471 }
3472 nnew = mm;
3473 }
3474 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of phi %d", j); u->dump(); });
3475 phase->igvn().replace_input_of(u, j, nnew);
3476 replaced = true;
3477 }
3478 }
3479 }
3480 if (replaced) {
3481 --i;
3482 }
3483 }
3484 } else if ((u->adr_type() == TypePtr::BOTTOM && u->Opcode() != Op_StrInflatedCopy) ||
3485 u->adr_type() == NULL) {
3486 assert(u->adr_type() != NULL ||
3487 u->Opcode() == Op_Rethrow ||
3488 u->Opcode() == Op_Return ||
3489 u->Opcode() == Op_SafePoint ||
3490 (u->is_CallStaticJava() && u->as_CallStaticJava()->uncommon_trap_request() != 0) ||
3491 (u->is_CallStaticJava() && u->as_CallStaticJava()->_entry_point == OptoRuntime::rethrow_stub()) ||
3492 u->Opcode() == Op_CallLeaf, "");
3493 Node* m = find_raw_mem(phase->ctrl_or_self(u), u, memory_nodes, phase);
3494 if (m != raw_mem) {
3495 if (mm == NULL || 1) {
3496 mm = allocate_merge_mem(raw_mem, alias, m, phase->get_ctrl(m), phase);
3497 }
3498 phase->igvn().replace_input_of(u, u->find_edge(raw_mem), mm);
3499 --i;
3500 }
3501 } else if (phase->C->get_alias_index(u->adr_type()) == alias) {
3502 Node* m = find_raw_mem(phase->ctrl_or_self(u), u, memory_nodes, phase);
3503 if (m != raw_mem) {
3504 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
3505 phase->igvn().replace_input_of(u, u->find_edge(raw_mem), m);
3506 --i;
3507 }
3508 }
3509 }
3510 }
3511 #ifdef ASSERT
3512 assert(raw_mem_phi->outcnt() > 0, "");
3513 for (int i = 0; i < phis.length(); i++) {
3514 Node* n = phis.at(i);
3515 assert(n->outcnt() > 0, "new phi must have uses now");
3516 }
3517 #endif
3518 }
3519
3520 void ShenandoahWriteBarrierNode::test_evacuation_in_progress(Node* ctrl, int alias, Node*& raw_mem, Node*& wb_mem,
3521 IfNode*& evacuation_iff, Node*& evac_in_progress,
3522 Node*& evac_not_in_progress, PhaseIdealLoop* phase) {
3523 IdealLoopTree *loop = phase->get_loop(ctrl);
3524 Node* thread = new ThreadLocalNode();
3525 phase->register_new_node(thread, ctrl);
3526 Node* offset = phase->igvn().MakeConX(in_bytes(JavaThread::gc_state_offset()));
3527 phase->set_ctrl(offset, phase->C->root());
3528 Node* gc_state_addr = new AddPNode(phase->C->top(), thread, offset);
3529 phase->register_new_node(gc_state_addr, ctrl);
3530 uint gc_state_idx = Compile::AliasIdxRaw;
3531 const TypePtr* gc_state_adr_type = NULL; // debug-mode-only argument
3532 debug_only(gc_state_adr_type = phase->C->get_adr_type(gc_state_idx));
3533
3534 Node* gc_state = new LoadUBNode(ctrl, raw_mem, gc_state_addr, gc_state_adr_type, TypeInt::BYTE, MemNode::unordered);
3535 phase->register_new_node(gc_state, ctrl);
3536
3537 if (ShenandoahWriteBarrierMemBar) {
3538 Node* mb = MemBarNode::make(phase->C, Op_MemBarAcquire, Compile::AliasIdxRaw);
3539 mb->init_req(TypeFunc::Control, ctrl);
3540 mb->init_req(TypeFunc::Memory, raw_mem);
3541 phase->register_control(mb, loop, ctrl);
3542 Node* ctrl_proj = new ProjNode(mb,TypeFunc::Control);
3543 phase->register_control(ctrl_proj, loop, mb);
3544 raw_mem = new ProjNode(mb, TypeFunc::Memory);
3545 phase->register_new_node(raw_mem, mb);
3546
3547 mb = MemBarNode::make(phase->C, Op_MemBarAcquire, alias);
3548 mb->init_req(TypeFunc::Control, ctrl_proj);
3549 mb->init_req(TypeFunc::Memory, wb_mem);
3550 phase->register_control(mb, loop, ctrl_proj);
3551 ctrl_proj = new ProjNode(mb,TypeFunc::Control);
3552 phase->register_control(ctrl_proj, loop, mb);
3553 wb_mem = new ProjNode(mb,TypeFunc::Memory);
3554 phase->register_new_node(wb_mem, mb);
3555
3556 ctrl = ctrl_proj;
3557 }
3558
3559 Node* evacuation_in_progress = gc_state;
3560 evacuation_in_progress = new AndINode(gc_state, phase->igvn().intcon(ShenandoahHeap::EVACUATION));
3561 phase->register_new_node(evacuation_in_progress, ctrl);
3562 Node* evacuation_in_progress_cmp = new CmpINode(evacuation_in_progress, phase->igvn().zerocon(T_INT));
3563 phase->register_new_node(evacuation_in_progress_cmp, ctrl);
3564 Node* evacuation_in_progress_test = new BoolNode(evacuation_in_progress_cmp, BoolTest::ne);
3565 phase->register_new_node(evacuation_in_progress_test, ctrl);
3566 evacuation_iff = new IfNode(ctrl, evacuation_in_progress_test, PROB_UNLIKELY(0.999), COUNT_UNKNOWN);
3567 phase->register_control(evacuation_iff, loop, ctrl);
3568
3569 assert(is_evacuation_in_progress_test(evacuation_iff), "Should match the shape");
3570 assert(is_gc_state_load(gc_state), "Should match the shape");
3571
3572 evac_not_in_progress = new IfFalseNode(evacuation_iff);
3573 phase->register_control(evac_not_in_progress, loop, evacuation_iff);
3574 evac_in_progress = new IfTrueNode(evacuation_iff);
3575 phase->register_control(evac_in_progress, loop, evacuation_iff);
3576 }
3577
3578 void ShenandoahWriteBarrierNode::evacuation_not_in_progress_null_check(Node*& c, Node*& val, Node* unc_ctrl, Node*& unc_region, PhaseIdealLoop* phase) {
3579 if (unc_ctrl != NULL) {
3580 // Clone the null check in this branch to allow implicit null check
3581 IdealLoopTree *loop = phase->get_loop(c);
3582 Node* iff = unc_ctrl->in(0);
3583 assert(iff->is_If(), "broken");
3584 Node* new_iff = iff->clone();
3585 new_iff->set_req(0, c);
3586 phase->register_control(new_iff, loop, c);
3587 Node* iffalse = new IfFalseNode(new_iff->as_If());
3588 phase->register_control(iffalse, loop, new_iff);
3589 Node* iftrue = new IfTrueNode(new_iff->as_If());
3590 phase->register_control(iftrue, loop, new_iff);
3591 c = iftrue;
3592 unc_region = new RegionNode(3);
3593 unc_region->init_req(1, iffalse);
3594 const Type *t = phase->igvn().type(val);
3595 assert(val->Opcode() == Op_CastPP, "expect cast to non null here");
3596 Node* uncasted_val = val->in(1);
3597 val = new CastPPNode(uncasted_val, t);
3598 val->init_req(0, c);
3599 phase->register_new_node(val, c);
3600 }
3601 }
3602
3603 void ShenandoahWriteBarrierNode::evacuation_not_in_progress(Node* c, Node* val, Node* unc_ctrl, Node* raw_mem, Node* wb_mem, Node* region,
3604 Node* val_phi, Node* mem_phi, Node* raw_mem_phi, Node*& unc_region, PhaseIdealLoop* phase) {
3605 evacuation_not_in_progress_null_check(c, val, unc_ctrl, unc_region, phase);
3606 region->init_req(1, c);
3607 if (ShenandoahWriteBarrierRB) {
3608 Node* rbfalse = new ShenandoahReadBarrierNode(c, wb_mem, val);
3609 phase->register_new_node(rbfalse, c);
3610 val_phi->init_req(1, rbfalse);
3611 } else {
3612 val_phi->init_req(1, val);
3613 }
3614 mem_phi->init_req(1, wb_mem);
3615 raw_mem_phi->init_req(1, raw_mem);
3616 }
3617
3618 void ShenandoahWriteBarrierNode::evacuation_in_progress_null_check(Node*& c, Node*& val, Node* evacuation_iff, Node* unc, Node* unc_ctrl,
3619 Node* unc_region, Unique_Node_List& uses, PhaseIdealLoop* phase) {
3620 if (unc != NULL) {
3621 // Clone the null check in this branch to allow implicit null check
3622 IdealLoopTree *loop = phase->get_loop(c);
3623 Node* iff = unc_ctrl->in(0);
3624 assert(iff->is_If(), "broken");
3625 Node* new_iff = iff->clone();
3626 new_iff->set_req(0, c);
3627 phase->register_control(new_iff, loop, c);
3628 Node* iffalse = new IfFalseNode(new_iff->as_If());
3629 phase->register_control(iffalse, loop, new_iff);
3630 Node* iftrue = new IfTrueNode(new_iff->as_If());
3631 phase->register_control(iftrue, loop, new_iff);
3632 c = iftrue;
3633 unc_region->init_req(2, iffalse);
3634
3635 Node* proj = iff->as_If()->proj_out(0);
3636 assert(proj != unc_ctrl, "bad projection");
3637 Node* use = proj->unique_ctrl_out();
3638
3639 assert(use == unc || use->is_Region(), "what else?");
3640
3641 uses.clear();
3642 if (use == unc) {
3643 phase->set_idom(use, unc_region, phase->dom_depth(unc_region)+1);
3644 for (uint i = 1; i < unc->req(); i++) {
3645 Node* n = unc->in(i);
3646 if (phase->has_ctrl(n) && phase->get_ctrl(n) == proj) {
3647 uses.push(n);
3648 }
3649 }
3650 } else {
3651 assert(use->is_Region(), "what else?");
3652 uint idx = 1;
3653 for (; use->in(idx) != proj; idx++);
3654 for (DUIterator_Fast imax, i = use->fast_outs(imax); i < imax; i++) {
3655 Node* u = use->fast_out(i);
3656 if (u->is_Phi() && phase->get_ctrl(u->in(idx)) == proj) {
3657 uses.push(u->in(idx));
3658 }
3659 }
3660 }
3661 for(uint next = 0; next < uses.size(); next++ ) {
3662 Node *n = uses.at(next);
3663 assert(phase->get_ctrl(n) == proj, "bad control");
3664 phase->set_ctrl_and_loop(n, unc_region);
3665 if (n->in(0) == proj) {
3666 phase->igvn().replace_input_of(n, 0, unc_region);
3667 }
3668 for (uint i = 0; i < n->req(); i++) {
3669 Node* m = n->in(i);
3670 if (m != NULL && phase->has_ctrl(m) && phase->get_ctrl(m) == proj) {
3671 uses.push(m);
3672 }
3673 }
3674 }
3675
3676 phase->igvn().rehash_node_delayed(use);
3677 int nb = use->replace_edge(proj, unc_region);
3678 assert(nb == 1, "only use expected");
3679 phase->register_control(unc_region, phase->ltree_root(), evacuation_iff);
3680
3681 phase->igvn().replace_input_of(iff, 1, phase->igvn().intcon(1));
3682 const Type *t = phase->igvn().type(val);
3683 assert(val->Opcode() == Op_CastPP, "expect cast to non null here");
3684 Node* uncasted_val = val->in(1);
3685 val = new CastPPNode(uncasted_val, t);
3686 val->init_req(0, c);
3687 phase->register_new_node(val, c);
3688 }
3689 }
3690
3691 void ShenandoahWriteBarrierNode::in_cset_fast_test(Node*& c, Node* rbtrue, Node* raw_mem, Node* wb_mem, Node* region, Node* val_phi, Node* mem_phi,
3692 Node* raw_mem_phi, PhaseIdealLoop* phase) {
3693 if (ShenandoahWriteBarrierCsetTestInIR) {
3694 IdealLoopTree *loop = phase->get_loop(c);
3695 Node* raw_rbtrue = new CastP2XNode(c, rbtrue);
3696 phase->register_new_node(raw_rbtrue, c);
3697 Node* cset_offset = new URShiftXNode(raw_rbtrue, phase->igvn().intcon(ShenandoahHeapRegion::region_size_bytes_shift_jint()));
3698 phase->register_new_node(cset_offset, c);
3699 Node* in_cset_fast_test_base_addr = phase->igvn().makecon(TypeRawPtr::make(ShenandoahHeap::in_cset_fast_test_addr()));
3700 phase->set_ctrl(in_cset_fast_test_base_addr, phase->C->root());
3701 Node* in_cset_fast_test_adr = new AddPNode(phase->C->top(), in_cset_fast_test_base_addr, cset_offset);
3702 phase->register_new_node(in_cset_fast_test_adr, c);
3703 uint in_cset_fast_test_idx = Compile::AliasIdxRaw;
3704 const TypePtr* in_cset_fast_test_adr_type = NULL; // debug-mode-only argument
3705 debug_only(in_cset_fast_test_adr_type = phase->C->get_adr_type(in_cset_fast_test_idx));
3706 Node* in_cset_fast_test_load = new LoadUBNode(c, raw_mem, in_cset_fast_test_adr, in_cset_fast_test_adr_type, TypeInt::BOOL, MemNode::unordered);
3707 phase->register_new_node(in_cset_fast_test_load, c);
3708 Node* in_cset_fast_test_cmp = new CmpINode(in_cset_fast_test_load, phase->igvn().zerocon(T_INT));
3709 phase->register_new_node(in_cset_fast_test_cmp, c);
3710 Node* in_cset_fast_test_test = new BoolNode(in_cset_fast_test_cmp, BoolTest::ne);
3711 phase->register_new_node(in_cset_fast_test_test, c);
3712 IfNode* in_cset_fast_test_iff = new IfNode(c, in_cset_fast_test_test, PROB_UNLIKELY(0.999), COUNT_UNKNOWN);
3713 phase->register_control(in_cset_fast_test_iff, loop, c);
3714
3715 Node* in_cset_fast_test_success = new IfFalseNode(in_cset_fast_test_iff);
3716 phase->register_control(in_cset_fast_test_success, loop, in_cset_fast_test_iff);
3717
3718 region->init_req(3, in_cset_fast_test_success);
3719 val_phi->init_req(3, rbtrue);
3720 mem_phi->init_req(3, wb_mem);
3721 raw_mem_phi->init_req(3, raw_mem);
3722
3723 Node* in_cset_fast_test_failure = new IfTrueNode(in_cset_fast_test_iff);
3724 phase->register_control(in_cset_fast_test_failure, loop, in_cset_fast_test_iff);
3725
3726 c = in_cset_fast_test_failure;
3727 }
3728 }
3729
3730 void ShenandoahWriteBarrierNode::evacuation_in_progress(Node* c, Node* val, Node* evacuation_iff, Node* unc, Node* unc_ctrl,
3731 Node* raw_mem, Node* wb_mem, Node* region, Node* val_phi, Node* mem_phi,
3732 Node* raw_mem_phi, Node* unc_region, int alias, Unique_Node_List& uses,
3733 PhaseIdealLoop* phase) {
3734 evacuation_in_progress_null_check(c, val, evacuation_iff, unc, unc_ctrl, unc_region, uses, phase);
3735
3736 IdealLoopTree *loop = phase->get_loop(c);
3737 Node* rbtrue = new ShenandoahReadBarrierNode(c, wb_mem, val);
3738 phase->register_new_node(rbtrue, c);
3739
3740 Node* in_cset_fast_test_failure = NULL;
3741 in_cset_fast_test(c, rbtrue, raw_mem, wb_mem, region, val_phi, mem_phi, raw_mem_phi, phase);
3742
3743 // The slow path stub consumes and produces raw memory in addition
3744 // to the existing memory edges
3745 Node* base = find_bottom_mem(c, phase);
3746
3747 MergeMemNode* mm = MergeMemNode::make(base);
3748 mm->set_memory_at(alias, wb_mem);
3749 mm->set_memory_at(Compile::AliasIdxRaw, raw_mem);
3750 phase->register_new_node(mm, c);
3751
3752 Node* call = new CallLeafNoFPNode(OptoRuntime::shenandoah_write_barrier_Type(), StubRoutines::shenandoah_wb_C(), "shenandoah_write_barrier", TypeRawPtr::BOTTOM);
3753 call->init_req(TypeFunc::Control, c);
3754 call->init_req(TypeFunc::I_O, phase->C->top());
3755 call->init_req(TypeFunc::Memory, mm);
3756 call->init_req(TypeFunc::FramePtr, phase->C->top());
3757 call->init_req(TypeFunc::ReturnAdr, phase->C->top());
3758 call->init_req(TypeFunc::Parms, rbtrue);
3759 phase->register_control(call, loop, c);
3760 Node* ctrl_proj = new ProjNode(call, TypeFunc::Control);
3761 phase->register_control(ctrl_proj, loop, call);
3762 Node* mem_proj = new ProjNode(call, TypeFunc::Memory);
3763 phase->register_new_node(mem_proj, call);
3764 Node* res_proj = new ProjNode(call, TypeFunc::Parms);
3765 phase->register_new_node(res_proj, call);
3766 Node* res = new CheckCastPPNode(ctrl_proj, res_proj, phase->igvn().type(val)->is_oopptr()->cast_to_nonconst());
3767 phase->register_new_node(res, ctrl_proj);
3768 region->init_req(2, ctrl_proj);
3769 val_phi->init_req(2, res);
3770 mem_phi->init_req(2, mem_proj);
3771 raw_mem_phi->init_req(2, mem_proj);
3772 phase->register_control(region, loop, evacuation_iff);
3773
3774 }
3775
3776 void ShenandoahWriteBarrierNode::pin_and_expand(PhaseIdealLoop* phase) {
3777 const bool trace = false;
3778
3779 // Collect raw memory state at CFG points in the entire graph and
3780 // record it in memory_nodes. Optimize the raw memory graph in the
3781 // process. Optimizing the memory graph also makes the memory graph
3782 // simpler.
3783 Node_List memory_nodes;
3784 collect_memory_nodes(Compile::AliasIdxRaw, memory_nodes, phase);
3785
3786 // Let's try to common write barriers again
3787 for (;;) {
3788 bool progress = false;
3789 for (int i = phase->C->shenandoah_barriers_count(); i > 0; i--) {
3790 ShenandoahBarrierNode* wb = phase->C->shenandoah_barrier(i-1);
3791 Node* ctrl = phase->get_ctrl(wb);
3792 if (wb->try_common(ctrl, phase) != NULL) {
3793 progress = true;
3794 }
3795 }
3796 if (!progress) {
3797 break;
3798 }
3799 }
3800
3801 for (int i = 0; i < phase->C->shenandoah_barriers_count(); i++) {
3802 ShenandoahWriteBarrierNode* wb = phase->C->shenandoah_barrier(i);
3803 Node* ctrl = phase->get_ctrl(wb);
3804
3805 Node* val = wb->in(ValueIn);
3806 if (ctrl->is_Proj() && ctrl->in(0)->is_CallJava()) {
3807 assert(is_dominator(phase->get_ctrl(val), ctrl->in(0)->in(0), val, ctrl->in(0), phase), "can't move");
3808 phase->set_ctrl(wb, ctrl->in(0)->in(0));
3809 } else if (ctrl->is_CallRuntime()) {
3810 assert(is_dominator(phase->get_ctrl(val), ctrl->in(0), val, ctrl, phase), "can't move");
3811 phase->set_ctrl(wb, ctrl->in(0));
3812 }
3813
3814 assert(wb->Opcode() == Op_ShenandoahWriteBarrier, "only for write barriers");
3815 // Look for a null check that dominates this barrier and move the
3816 // barrier right after the null check to enable implicit null
3817 // checks
3818 wb->pin_and_expand_move_barrier(phase);
3819
3820 ctrl = phase->get_ctrl(wb);
3821 wb->pin_and_expand_helper(phase);
3822 }
3823
3824 Unique_Node_List uses;
3825 Unique_Node_List uses_to_ignore;
3826 for (int i = phase->C->shenandoah_barriers_count(); i > 0; i--) {
3827 int cnt = phase->C->shenandoah_barriers_count();
3828 ShenandoahWriteBarrierNode* wb = phase->C->shenandoah_barrier(i-1);
3829
3830 uint last = phase->C->unique();
3831 Node* ctrl = phase->get_ctrl(wb);
3832
3833 Node* raw_mem = find_raw_mem(ctrl, wb, memory_nodes, phase);
3834 Node* init_raw_mem = raw_mem;
3835 Node* raw_mem_for_ctrl = find_raw_mem(ctrl, NULL, memory_nodes, phase);
3836 int alias = phase->C->get_alias_index(wb->adr_type());
3837 Node* wb_mem = wb->in(Memory);
3838
3839 Node* val = wb->in(ValueIn);
3840 Node* wbproj = wb->find_out_with(Op_ShenandoahWBMemProj);
3841 IdealLoopTree *loop = phase->get_loop(ctrl);
3842
3843 assert(val->Opcode() != Op_ShenandoahWriteBarrier || phase->C->has_irreducible_loop(), "No chain of write barriers");
3844
3845 CallStaticJavaNode* unc = wb->pin_and_expand_null_check(phase->igvn());
3846 Node* unc_ctrl = NULL;
3847 if (unc != NULL) {
3848 if (val->in(0) != ctrl) {
3849 unc = NULL;
3850 } else {
3851 unc_ctrl = val->in(0);
3852 }
3853 }
3854
3855 Node* uncasted_val = val;
3856 if (unc != NULL) {
3857 uncasted_val = val->in(1);
3858 }
3859
3860 Node* evac_in_progress = NULL;
3861 Node* evac_not_in_progress = NULL;
3862 IfNode* evacuation_iff = NULL;
3863 test_evacuation_in_progress(ctrl, alias, raw_mem, wb_mem, evacuation_iff, evac_in_progress, evac_not_in_progress, phase);
3864
3865 Node* region = new RegionNode(4);
3866 Node* val_phi = new PhiNode(region, val->bottom_type()->is_oopptr()->cast_to_nonconst());
3867 Node* mem_phi = PhiNode::make(region, wb_mem, Type::MEMORY, phase->C->alias_type(wb->adr_type())->adr_type());
3868 Node* raw_mem_phi = PhiNode::make(region, raw_mem, Type::MEMORY, TypeRawPtr::BOTTOM);
3869
3870 Node* unc_region = NULL;
3871 evacuation_not_in_progress(evac_not_in_progress, val, unc_ctrl, raw_mem, wb_mem,
3872 region, val_phi, mem_phi, raw_mem_phi, unc_region,
3873 phase);
3874
3875 evacuation_in_progress(evac_in_progress, val, evacuation_iff, unc, unc_ctrl,
3876 raw_mem, wb_mem, region, val_phi, mem_phi, raw_mem_phi,
3877 unc_region, alias, uses,
3878 phase);
3879 Node* out_val = val_phi;
3880 phase->register_new_node(val_phi, region);
3881 phase->register_new_node(mem_phi, region);
3882 phase->register_new_node(raw_mem_phi, region);
3883
3884 // Update the control of all nodes that should be after the
3885 // barrier control flow
3886 uses.clear();
3887 // Every node that is control dependent on the barrier's input
3888 // control will be after the expanded barrier. The raw memory (if
3889 // its memory is control dependent on the barrier's input control)
3890 // must stay above the barrier.
3891 uses_to_ignore.clear();
3892 if (phase->has_ctrl(init_raw_mem) && phase->get_ctrl(init_raw_mem) == ctrl && !init_raw_mem->is_Phi()) {
3893 uses_to_ignore.push(init_raw_mem);
3894 }
3895 for (uint next = 0; next < uses_to_ignore.size(); next++) {
3896 Node *n = uses_to_ignore.at(next);
3897 for (uint i = 0; i < n->req(); i++) {
3898 Node* in = n->in(i);
3899 if (in != NULL && phase->has_ctrl(in) && phase->get_ctrl(in) == ctrl) {
3900 uses_to_ignore.push(in);
3901 }
3902 }
3903 }
3904 for (DUIterator_Fast imax, i = ctrl->fast_outs(imax); i < imax; i++) {
3905 Node* u = ctrl->fast_out(i);
3906 if (u->_idx < last &&
3907 u != wb &&
3908 !uses_to_ignore.member(u) &&
3909 (u->in(0) != ctrl || (!u->is_Region() && !u->is_Phi())) &&
3910 (ctrl->Opcode() != Op_CatchProj || u->Opcode() != Op_CreateEx)) {
3911 Node* old_c = phase->ctrl_or_self(u);
3912 Node* c = old_c;
3913 if (c != ctrl ||
3914 is_dominator_same_ctrl(old_c, wb, u, phase) ||
3915 u->is_g1_marking_load()) {
3916 phase->igvn().rehash_node_delayed(u);
3917 int nb = u->replace_edge(ctrl, region);
3918 if (u->is_CFG()) {
3919 if (phase->idom(u) == ctrl) {
3920 phase->set_idom(u, region, phase->dom_depth(region));
3921 }
3922 } else if (phase->get_ctrl(u) == ctrl) {
3923 assert(u != init_raw_mem, "should leave input raw mem above the barrier");
3924 uses.push(u);
3925 }
3926 assert(nb == 1, "more than 1 ctrl input?");
3927 --i, imax -= nb;
3928 }
3929 }
3930 }
3931
3932 if (wbproj != NULL) {
3933 phase->igvn().replace_input_of(wbproj, 0, phase->C->top());
3934 phase->lazy_replace(wbproj, mem_phi);
3935 }
3936 if (unc != NULL) {
3937 for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) {
3938 Node* u = val->fast_out(i);
3939 Node* c = phase->ctrl_or_self(u);
3940 if (u != wb && (c != ctrl || is_dominator_same_ctrl(c, wb, u, phase))) {
3941 phase->igvn().rehash_node_delayed(u);
3942 int nb = u->replace_edge(val, out_val);
3943 --i, imax -= nb;
3944 }
3945 }
3946 if (val->outcnt() == 0) {
3947 phase->lazy_update(val, out_val);
3948 phase->igvn()._worklist.push(val);
3949 }
3950 }
3951 phase->lazy_replace(wb, out_val);
3952
3953 follow_barrier_uses(mem_phi, ctrl, uses, phase);
3954 follow_barrier_uses(out_val, ctrl, uses, phase);
3955
3956 for(uint next = 0; next < uses.size(); next++ ) {
3957 Node *n = uses.at(next);
3958 assert(phase->get_ctrl(n) == ctrl, "bad control");
3959 assert(n != init_raw_mem, "should leave input raw mem above the barrier");
3960 phase->set_ctrl(n, region);
3961 follow_barrier_uses(n, ctrl, uses, phase);
3962 }
3963
3964 // The slow path call produces memory: hook the raw memory phi
3965 // from the expanded write barrier with the rest of the graph
3966 // which may require adding memory phis at every post dominated
3967 // region and at enclosing loop heads. Use the memory state
3968 // collected in memory_nodes to fix the memory graph. Update that
3969 // memory state as we go.
3970 fix_raw_mem(ctrl,region, init_raw_mem, raw_mem_for_ctrl, raw_mem_phi, memory_nodes, uses, phase);
3971 assert(phase->C->shenandoah_barriers_count() == cnt - 1, "not replaced");
3972 }
3973
3974 assert(phase->C->shenandoah_barriers_count() == 0, "all write barrier nodes should have been replaced");
3975 }
3976
3977 void ShenandoahWriteBarrierNode::move_evacuation_test_out_of_loop(IfNode* iff, PhaseIdealLoop* phase) {
3978 // move test and its mem barriers out of the loop
3979 assert(is_evacuation_in_progress_test(iff), "inconsistent");
3980
3981 if (ShenandoahWriteBarrierMemBar) {
3982 IdealLoopTree *loop = phase->get_loop(iff);
3983 Node* loop_head = loop->_head;
3984 Node* entry_c = loop_head->in(LoopNode::EntryControl);
3985 IdealLoopTree *entry_loop = phase->get_loop(entry_c);
3986
3987 GrowableArray<Node*> new_mbs;
3988 Node* c = iff->in(0);
3989 MemBarNode* mb = NULL;
3990 do {
3991 Node* proj_ctrl = c;
3992 assert(c->is_Proj(), "proj expected");
3993 mb = proj_ctrl->in(0)->as_MemBar();
3994 c = c->in(0)->in(0);
3995
3996 Node* proj_mem = mb->proj_out(TypeFunc::Memory);
3997
3998 MemBarNode* new_mb = mb->clone()->as_MemBar();;
3999 Node* new_proj_ctrl = new ProjNode(new_mb,TypeFunc::Control);
4000 Node* new_proj_mem = new ProjNode(new_mb,TypeFunc::Memory);
4001
4002 int alias = phase->C->get_alias_index(mb->adr_type());
4003 Node* mem_ctrl = NULL;
4004 Node* mem = dom_mem(mb, loop_head, alias, mem_ctrl, phase);
4005 new_mb->set_req(TypeFunc::Memory, mem);
4006 phase->register_new_node(new_proj_mem, new_mb);
4007 fix_memory_uses(mem, new_mb, new_proj_mem, entry_c, alias, phase);
4008 assert(new_proj_mem->outcnt() >= 1, "memory projection is disconnected");
4009 new_mbs.push(new_proj_ctrl);
4010 } while (mb->adr_type() != TypeRawPtr::BOTTOM);
4011
4012 c = entry_c;
4013 for (int i = new_mbs.length()-1; i >= 0; i--) {
4014 Node* proj_ctrl = new_mbs.at(i);
4015 Node* mb = proj_ctrl->in(0);
4016 mb->set_req(0, c);
4017 phase->set_idom(mb, mb->in(0), phase->dom_depth(mb->in(0)));
4018 phase->set_idom(proj_ctrl, mb, phase->dom_depth(mb));
4019 c = proj_ctrl;
4020 phase->register_control(mb, entry_loop, mb->in(0));
4021 phase->register_control(proj_ctrl, entry_loop, mb);
4022 }
4023 phase->igvn().replace_input_of(loop_head, LoopNode::EntryControl, c);
4024 phase->set_idom(loop_head, c, phase->dom_depth(c));
4025 //phase->recompute_dom_depth();
4026
4027 Node* load = iff->in(1)->in(1)->in(1)->in(1);
4028 assert(load->Opcode() == Op_LoadUB, "inconsistent");
4029 phase->igvn().replace_input_of(load, MemNode::Memory, new_mbs.at(new_mbs.length()-1)->in(0)->in(TypeFunc::Memory));
4030 phase->igvn().replace_input_of(load, 0, entry_c);
4031 phase->set_ctrl_and_loop(load, entry_c);
4032
4033 c = iff->in(0);
4034 for (;;) {
4035 Node* next = c->in(0)->in(0);
4036 assert(c->is_Proj(), "proj expected");
4037 Node* proj_ctrl = c;
4038 MemBarNode* mb = proj_ctrl->in(0)->as_MemBar();
4039 Node* proj_mem = mb->proj_out(TypeFunc::Memory);
4040 Node* ctrl = mb->in(TypeFunc::Control);
4041 Node* mem = mb->in(TypeFunc::Memory);
4042
4043 phase->lazy_replace(proj_mem, mem);
4044 phase->lazy_replace(proj_ctrl, ctrl);
4045 phase->lazy_replace(mb, ctrl);
4046 loop->_body.yank(proj_ctrl);
4047 loop->_body.yank(proj_mem);
4048 loop->_body.yank(mb);
4049 if (mb->adr_type() == TypeRawPtr::BOTTOM) {
4050 break;
4051 }
4052 c = next;
4053 }
4054
4055 assert(phase->is_dominator(phase->get_ctrl(load->in(MemNode::Address)), entry_c), "address not out of loop?");
4056 } else {
4057 IdealLoopTree *loop = phase->get_loop(iff);
4058 Node* loop_head = loop->_head;
4059 Node* entry_c = loop_head->in(LoopNode::EntryControl);
4060
4061 Node* load = iff->in(1)->in(1)->in(1);
4062 assert(load->Opcode() == Op_LoadUB, "inconsistent");
4063 Node* mem_ctrl = NULL;
4064 }
4065 }
4066
4067 void ShenandoahWriteBarrierNode::backtoback_evacs(IfNode* iff, IfNode* dom_if, PhaseIdealLoop* phase) {
4068 if (!ShenandoahWriteBarrierMemBar) {
4069 return;
4070 }
4071 // move all mem barriers from this evac test to the dominating one,
4072 // removing duplicates in the process
4073 IdealLoopTree *loop = phase->get_loop(dom_if);
4074 Node* c1 = iff->in(0);
4075 Node* mb1 = NULL;
4076 GrowableArray<Node*> new_mbs;
4077 for(;;) {
4078 mb1 = c1->in(0);
4079 c1 = c1->in(0)->in(0);
4080 assert(mb1->Opcode() == Op_MemBarAcquire, "mem bar expected");
4081 if (mb1->adr_type() == TypeRawPtr::BOTTOM) {
4082 phase->lazy_replace(mb1->as_MemBar()->proj_out(TypeFunc::Memory), mb1->in(TypeFunc::Memory));
4083 break;
4084 }
4085 Node* c2 = dom_if->in(0);
4086 Node* mb2 = NULL;
4087 do {
4088 mb2 = c2->in(0);
4089 c2 = c2->in(0)->in(0);
4090 assert(mb2->Opcode() == Op_MemBarAcquire, "mem bar expected");
4091 if (mb2->adr_type() == TypeRawPtr::BOTTOM) {
4092 // Barrier on same slice doesn't exist at dominating if:
4093 // move barrier up
4094 MemBarNode* mb = mb1->clone()->as_MemBar();
4095 Node* proj_ctrl = new ProjNode(mb,TypeFunc::Control);
4096 Node* proj_mem = new ProjNode(mb,TypeFunc::Memory);
4097 int alias = phase->C->get_alias_index(mb->adr_type());
4098 Node* mem_ctrl = NULL;
4099 Node* mem = dom_mem(mb1, dom_if->in(0), alias, mem_ctrl, phase);
4100 mb->set_req(TypeFunc::Memory, mem);
4101 phase->register_new_node(proj_mem, mb);
4102 fix_memory_uses(mem, mb, proj_mem, dom_if->in(0), alias, phase);
4103 assert(proj_mem->outcnt() >= 1, "memory projection is disconnected");
4104 new_mbs.push(proj_ctrl);
4105 break;
4106 }
4107 } while (mb2->adr_type() != mb1->adr_type());
4108 phase->lazy_replace(mb1->as_MemBar()->proj_out(TypeFunc::Memory), mb1->in(TypeFunc::Memory));
4109 }
4110 if (new_mbs.length() > 0) {
4111 Node* c = dom_if->in(0);
4112 for (int i = 0; i < new_mbs.length(); i++) {
4113 Node* proj_ctrl = new_mbs.at(i);
4114 Node* mb = proj_ctrl->in(0);
4115 mb->set_req(0, c);
4116 phase->set_idom(mb, mb->in(0), phase->dom_depth(mb->in(0)));
4117 phase->set_idom(proj_ctrl, mb, phase->dom_depth(mb));
4118 c = proj_ctrl;
4119 phase->register_control(mb, loop, mb->in(0));
4120 phase->register_control(proj_ctrl, loop, mb);
4121 }
4122 phase->igvn().replace_input_of(dom_if, 0, c);
4123 phase->set_idom(dom_if, dom_if->in(0), phase->dom_depth(dom_if->in(0)));
4124 }
4125 Node* c = iff->in(0);
4126 for (;;) {
4127 Node* next = c->in(0)->in(0);
4128 assert(c->is_Proj(), "proj expected");
4129 MemBarNode* mb = c->in(0)->as_MemBar();
4130 Node* proj_ctrl = c;
4131 Node* ctrl = mb->in(TypeFunc::Control);
4132
4133 phase->lazy_replace(proj_ctrl, ctrl);
4134 phase->lazy_replace(mb, ctrl);
4135 if (mb->adr_type() == TypeRawPtr::BOTTOM) {
4136 break;
4137 }
4138 c = next;
4139 }
4140 }
4141
4142 void ShenandoahWriteBarrierNode::merge_back_to_back_evacuation_tests(Node* n, PhaseIdealLoop* phase) {
4143 if (phase->identical_backtoback_ifs(n)) {
4144 Node* n_ctrl = ShenandoahWriteBarrierNode::evacuation_in_progress_test_ctrl(n);
4145 if (phase->can_split_if(n_ctrl)) {
4146 IfNode* dom_if = phase->idom(n_ctrl)->as_If();
4147 ShenandoahWriteBarrierNode::backtoback_evacs(n->as_If(), dom_if, phase);
4148 PhiNode* bolphi = PhiNode::make_blank(n_ctrl, n->in(1));
4149 Node* proj_true = dom_if->proj_out(1);
4150 Node* proj_false = dom_if->proj_out(0);
4151 Node* con_true = phase->igvn().makecon(TypeInt::ONE);
4152 Node* con_false = phase->igvn().makecon(TypeInt::ZERO);
4153
4154 for (uint i = 1; i < n_ctrl->req(); i++) {
4155 if (phase->is_dominator(proj_true, n_ctrl->in(i))) {
4156 bolphi->init_req(i, con_true);
4157 } else {
4158 assert(phase->is_dominator(proj_false, n_ctrl->in(i)), "bad if");
4159 bolphi->init_req(i, con_false);
4160 }
4161 }
4162 phase->register_new_node(bolphi, n_ctrl);
4163 phase->igvn().replace_input_of(n, 1, bolphi);
4164 phase->do_split_if(n);
4165 }
4166 }
4167 }
4168
4169 void ShenandoahWriteBarrierNode::optimize_after_expansion(const Node_List& evacuation_tests, const Node_List& gc_state_loads, Node_List &old_new, PhaseIdealLoop* phase) {
4170 bool progress;
4171 do {
4172 progress = false;
4173 for (uint i = 0; i < gc_state_loads.size(); i++) {
4174 Node* n = gc_state_loads.at(i);
4175 if (n->outcnt() != 0) {
4176 progress |= ShenandoahWriteBarrierNode::try_common_gc_state_load(n, phase);
4177 }
4178 }
4179 } while(progress);
4180
4181 for (uint i = 0; i < evacuation_tests.size(); i++) {
4182 Node* n = evacuation_tests.at(i);
4183 assert(is_evacuation_in_progress_test(n), "only evacuation test");
4184 merge_back_to_back_evacuation_tests(n, phase);
4185 }
4186 if (!phase->C->major_progress()) {
4187 VectorSet seen(Thread::current()->resource_area());
4188 for (uint i = 0; i < evacuation_tests.size(); i++) {
4189 Node* n = evacuation_tests.at(i);
4190 IdealLoopTree* loop = phase->get_loop(n);
4191 if (loop != phase->ltree_root() &&
4192 loop->_child == NULL &&
4193 !loop->_irreducible) {
4194 LoopNode* head = loop->_head->as_Loop();
4195 if ((!head->is_CountedLoop() || head->as_CountedLoop()->is_main_loop() || head->as_CountedLoop()->is_normal_loop()) &&
4196 !seen.test_set(head->_idx) &&
4197 loop->policy_unswitching(phase)) {
4198 IfNode* iff = phase->find_unswitching_candidate(loop);
4199 if (iff != NULL && is_evacuation_in_progress_test(iff)) {
4200 if (head->is_strip_mined()) {
4201 head->verify_strip_mined(0);
4202 head->clear_strip_mined();
4203 head->in(LoopNode::EntryControl)->as_Loop()->clear_strip_mined();
4204 }
4205 phase->do_unswitching(loop, old_new);
4206 }
4207 }
4208 }
4209 }
4210 }
4211 }
4212
4213 #ifdef ASSERT
4214 void ShenandoahBarrierNode::verify_raw_mem(RootNode* root) {
4215 const bool trace = false;
4216 ResourceMark rm;
4217 Unique_Node_List nodes;
4218 Unique_Node_List controls;
4219 Unique_Node_List memories;
4220
4221 nodes.push(root);
4222 for (uint next = 0; next < nodes.size(); next++) {
4223 Node *n = nodes.at(next);
4224 if (n->Opcode() == Op_CallLeafNoFP && n->as_Call()->_entry_point == StubRoutines::shenandoah_wb_C()) {
4225 controls.push(n);
4226 if (trace) { tty->print("XXXXXX verifying"); n->dump(); }
4227 for (uint next2 = 0; next2 < controls.size(); next2++) {
4228 Node *m = controls.at(next2);
4229 if (!m->is_Loop() || controls.member(m->in(LoopNode::EntryControl)) || 1) {
4230 for (DUIterator_Fast imax, i = m->fast_outs(imax); i < imax; i++) {
4231 Node* u = m->fast_out(i);
4232 if (u->is_CFG() && !u->is_Root()) {
4233 if (trace) { tty->print("XXXXXX pushing control"); u->dump(); }
4234 controls.push(u);
4235 }
4236 }
4237 }
4238 }
4239 memories.push(n->as_Call()->proj_out(TypeFunc::Memory));
4240 for (uint next2 = 0; next2 < memories.size(); next2++) {
4241 Node *m = memories.at(next2);
4242 assert(m->bottom_type() == Type::MEMORY, "");
4243 if (!m->is_Phi() || !m->in(0)->is_Loop() || controls.member(m->in(0)->in(LoopNode::EntryControl)) || 1) {
4244 for (DUIterator_Fast imax, i = m->fast_outs(imax); i < imax; i++) {
4245 Node* u = m->fast_out(i);
4246 if (u->bottom_type() == Type::MEMORY && (u->is_Mem() || u->is_ClearArray())) {
4247 if (trace) { tty->print("XXXXXX pushing memory"); u->dump(); }
4248 memories.push(u);
4249 } else if (u->is_LoadStore()) {
4250 if (trace) { tty->print("XXXXXX pushing memory"); u->find_out_with(Op_SCMemProj)->dump(); }
4251 memories.push(u->find_out_with(Op_SCMemProj));
4252 } else if (u->is_MergeMem() && u->as_MergeMem()->memory_at(Compile::AliasIdxRaw) == m) {
4253 if (trace) { tty->print("XXXXXX pushing memory"); u->dump(); }
4254 memories.push(u);
4255 } else if (u->is_Phi()) {
4256 assert(u->bottom_type() == Type::MEMORY, "");
4257 if (u->adr_type() == TypeRawPtr::BOTTOM || u->adr_type() == TypePtr::BOTTOM) {
4258 assert(controls.member(u->in(0)), "");
4259 if (trace) { tty->print("XXXXXX pushing memory"); u->dump(); }
4260 memories.push(u);
4261 }
4262 } else if (u->is_SafePoint() || u->is_MemBar()) {
4263 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
4264 Node* uu = u->fast_out(j);
4265 if (uu->bottom_type() == Type::MEMORY) {
4266 if (trace) { tty->print("XXXXXX pushing memory"); uu->dump(); }
4267 memories.push(uu);
4268 }
4269 }
4270 }
4271 }
4272 }
4273 }
4274 for (uint next2 = 0; next2 < controls.size(); next2++) {
4275 Node *m = controls.at(next2);
4276 if (m->is_Region()) {
4277 bool all_in = true;
4278 for (uint i = 1; i < m->req(); i++) {
4279 if (!controls.member(m->in(i))) {
4280 all_in = false;
4281 break;
4282 }
4283 }
4284 if (trace) { tty->print("XXX verifying %s", all_in ? "all in" : ""); m->dump(); }
4285 bool found_phi = false;
4286 for (DUIterator_Fast jmax, j = m->fast_outs(jmax); j < jmax && !found_phi; j++) {
4287 Node* u = m->fast_out(j);
4288 if (u->is_Phi() && memories.member(u)) {
4289 found_phi = true;
4290 for (uint i = 1; i < u->req() && found_phi; i++) {
4291 Node* k = u->in(i);
4292 if (memories.member(k) != controls.member(m->in(i))) {
4293 found_phi = false;
4294 }
4295 }
4296 }
4297 }
4298 assert(found_phi || all_in, "");
4299 }
4300 }
4301 controls.clear();
4302 memories.clear();
4303 }
4304 for( uint i = 0; i < n->len(); ++i ) {
4305 Node *m = n->in(i);
4306 if (m != NULL) {
4307 nodes.push(m);
4308 }
4309 }
4310 }
4311 }
4312 #endif
4313
4314 static bool is_on_null_check_path(Block* b, Block* null_check_block) {
4315 if (null_check_block == NULL) {
4316 return false;
4317 }
4318 do {
4319 assert(null_check_block->_num_succs == 1, "only one succ on the path to unc");
4320 if (b == null_check_block) {
4321 return true;
4322 }
4323 null_check_block = null_check_block->_succs[0];
4324 } while(!null_check_block->head()->is_Root());
4325
4326 return false;
4327 }
4328
4329 int PhaseCFG::replace_uses_with_shenandoah_barrier_helper(Node* n, Node* use, Node* val, Block* block, Block* null_check_block) {
4330 int nb = 0;
4331 Block* buse = get_block_for_node(use);
4332 if (is_on_null_check_path(buse, null_check_block)) {
4333 return 0;
4334 }
4335 if (use->is_Phi()) {
4336 for (uint j = 1; j < use->req(); j++) {
4337 if (use->in(j) == val) {
4338 Block* b = get_block_for_node(use->in(0)->in(j));
4339 if ((block != b && block->dom_lca(b) == block) ||
4340 block == b) {
4341 use->set_req(j, n);
4342 nb++;
4343 }
4344 }
4345 }
4346 } else {
4347 if ((block != buse && block->dom_lca(buse) == block) ||
4348 (block == buse && !use->is_scheduled())) {
4349 // Let precedence edges alone (can confuse anti-dependence verification code)
4350 for (uint i = 0; i < use->req(); i++) {
4351 if (use->in(i) == val) {
4352 use->set_req(i, n);
4353 nb++;
4354 }
4355 }
4356 assert(nb > 0 || use->find_prec_edge(val) != -1, "no replacement?");
4357 }
4358 }
4359
4360 return nb;
4361 }
4362
4363 void PhaseCFG::replace_uses_with_shenandoah_barrier(Node* n, Block* block, Node_List& worklist, GrowableArray<int>& ready_cnt, uint max_idx, uint& phi_cnt) {
4364 // Replace all uses of barrier's input that are dominated by the
4365 // barrier with the value returned by the barrier: no need to keep
4366 // both live.
4367 if (n->is_Mach() && n->as_Mach()->ideal_Opcode() == Op_ShenandoahReadBarrier) {
4368 MachNullCheckNode* null_check = NULL;
4369 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax && null_check == NULL; i++) {
4370 Node* use = n->fast_out(i);
4371 if (use->is_MachNullCheck()) {
4372 null_check = use->as_MachNullCheck();
4373 }
4374 }
4375 Block* null_check_block = NULL;
4376 if (null_check != NULL) {
4377 Node* proj = null_check->find_out_with(Op_IfTrue);
4378 Node* head = proj->unique_out();
4379 null_check_block = get_block_for_node(head);
4380 }
4381
4382 Node* val = n->in(ShenandoahBarrierNode::ValueIn);
4383 if (!val->bottom_type()->isa_narrowoop()) {
4384 for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) {
4385 Node* use = val->fast_out(i);
4386 if (use != n) {
4387 int nb = replace_uses_with_shenandoah_barrier_helper(n, use, val, block, null_check_block);
4388 if (nb > 0) {
4389 --i; imax -= nb;
4390 }
4391 }
4392 }
4393 } else {
4394 for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) {
4395 Node* u = val->fast_out(i);
4396 if (u->is_Mach() && u->as_Mach()->ideal_Opcode() == Op_DecodeN) {
4397 int projs = 0;
4398 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
4399 Node* uu = u->fast_out(j);
4400 assert(!uu->is_MachTemp(), "");
4401 if (uu->is_MachProj() && uu->outcnt() == 0) {
4402 projs++;
4403 } else {
4404 int nb = replace_uses_with_shenandoah_barrier_helper(n, uu, u, block, null_check_block);
4405 if (nb > 0) {
4406 if (!u->is_scheduled()) {
4407 push_ready_nodes(n, uu, block, ready_cnt, worklist, max_idx, nb);
4408 }
4409 --j; jmax -= nb;
4410 }
4411 }
4412 }
4413 // The DecodeN may have gone dead
4414 if (u->outcnt() - projs == 0) {
4415 u->disconnect_inputs(NULL, C);
4416 Block* bu = get_block_for_node(u);
4417 unmap_node_from_block(u);
4418 if (bu == block) {
4419 if (u->is_scheduled()) {
4420 block->find_remove(u);
4421 phi_cnt--;
4422 } else {
4423 worklist.yank(u);
4424 block->remove_node(block->end_idx()-1);
4425 }
4426 } else {
4427 bu->find_remove(u);
4428 }
4429 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
4430 Node* uu = u->fast_out(j);
4431 assert(uu->is_MachProj() && uu->outcnt() == 0, "");
4432 assert(bu == get_block_for_node(uu), "");
4433 uu->disconnect_inputs(NULL, C);
4434 --j; --jmax;
4435 unmap_node_from_block(uu);
4436 if (bu == block) {
4437 if (u->is_scheduled()) {
4438 block->find_remove(uu);
4439 phi_cnt--;
4440 } else {
4441 worklist.yank(uu);
4442 block->remove_node(block->end_idx()-1);
4443 }
4444 } else {
4445 bu->find_remove(uu);
4446 }
4447 assert(uu->is_scheduled() == u->is_scheduled(), "");
4448 }
4449 --i; --imax;
4450 }
4451 }
4452 }
4453 }
4454 }
4455 }