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 "gc/shenandoah/c2/shenandoahSupport.hpp"
37 #include "gc/shenandoah/c2/shenandoahBarrierSetC2.hpp"
38 #include "opto/subnode.hpp"
39
40 Node* ShenandoahBarrierNode::skip_through_barrier(Node* n) {
41 if (n == NULL) {
42 return NULL;
43 } else if (n->is_ShenandoahBarrier()) {
44 return n->in(ValueIn);
45 } else if (n->is_Phi() &&
46 n->req() == 3 &&
47 n->in(1) != NULL &&
48 n->in(1)->is_ShenandoahBarrier() &&
49 n->in(2) != NULL &&
50 n->in(2)->bottom_type() == TypePtr::NULL_PTR &&
51 n->in(0) != NULL &&
52 n->in(0)->in(1) != NULL &&
53 n->in(0)->in(1)->is_IfProj() &&
54 n->in(0)->in(2) != NULL &&
55 n->in(0)->in(2)->is_IfProj() &&
56 n->in(0)->in(1)->in(0) != NULL &&
57 n->in(0)->in(1)->in(0) == n->in(0)->in(2)->in(0) &&
58 n->in(1)->in(ValueIn)->Opcode() == Op_CastPP) {
59 Node* iff = n->in(0)->in(1)->in(0);
60 Node* res = n->in(1)->in(ValueIn)->in(1);
61 if (iff->is_If() &&
62 iff->in(1) != NULL &&
63 iff->in(1)->is_Bool() &&
64 iff->in(1)->as_Bool()->_test._test == BoolTest::ne &&
65 iff->in(1)->in(1) != NULL &&
66 iff->in(1)->in(1)->Opcode() == Op_CmpP &&
67 iff->in(1)->in(1)->in(1) != NULL &&
68 iff->in(1)->in(1)->in(1) == res &&
69 iff->in(1)->in(1)->in(2) != NULL &&
70 iff->in(1)->in(1)->in(2)->bottom_type() == TypePtr::NULL_PTR) {
71 return res;
72 }
73 }
74 return n;
75 }
76
77 bool ShenandoahBarrierNode::needs_barrier(PhaseGVN* phase, ShenandoahBarrierNode* orig, Node* n, Node* rb_mem, bool allow_fromspace) {
78 Unique_Node_List visited;
79 return needs_barrier_impl(phase, orig, n, rb_mem, allow_fromspace, visited);
80 }
81
82 bool ShenandoahBarrierNode::needs_barrier_impl(PhaseGVN* phase, ShenandoahBarrierNode* orig, Node* n, Node* rb_mem, bool allow_fromspace, Unique_Node_List &visited) {
83
84 if (visited.member(n)) {
85 return false; // Been there.
86 }
87 visited.push(n);
88
89 if (n->is_Allocate()) {
90 // tty->print_cr("killed barrier for newly allocated object");
91 return false;
92 }
93
94 if (n->is_CallJava() || n->Opcode() == Op_CallLeafNoFP) {
95 return true;
96 }
97
98 const Type* type = phase->type(n);
99 if (type == Type::TOP) {
100 return false;
101 }
102 if (type->make_ptr()->higher_equal(TypePtr::NULL_PTR)) {
103 // tty->print_cr("killed barrier for NULL object");
104 return false;
105 }
106 if (type->make_oopptr() && type->make_oopptr()->const_oop() != NULL) {
107 // tty->print_cr("killed barrier for constant object");
108 return ShenandoahBarriersForConst;
109 }
110
111 if (ShenandoahOptimizeStableFinals) {
112 const TypeAryPtr* ary = type->isa_aryptr();
113 if (ary && ary->is_stable() && allow_fromspace) {
114 return false;
115 }
116 }
117
118 if (n->is_CheckCastPP() || n->is_ConstraintCast()) {
119 return needs_barrier_impl(phase, orig, n->in(1), rb_mem, allow_fromspace, visited);
120 }
121 if (n->is_Parm()) {
122 return true;
123 }
124 if (n->is_Proj()) {
125 return needs_barrier_impl(phase, orig, n->in(0), rb_mem, allow_fromspace, visited);
126 }
127 if (n->is_Phi()) {
128 bool need_barrier = false;
129 for (uint i = 1; i < n->req() && ! need_barrier; i++) {
130 Node* input = n->in(i);
131 if (input == NULL) {
132 need_barrier = true; // Phi not complete yet?
133 } else if (needs_barrier_impl(phase, orig, input, rb_mem, allow_fromspace, visited)) {
134 need_barrier = true;
135 }
136 }
137 return need_barrier;
138 }
139 if (n->is_CMove()) {
140 return needs_barrier_impl(phase, orig, n->in(CMoveNode::IfFalse), rb_mem, allow_fromspace, visited) ||
141 needs_barrier_impl(phase, orig, n->in(CMoveNode::IfTrue ), rb_mem, allow_fromspace, visited);
142 }
143 if (n->Opcode() == Op_CreateEx) {
144 return true;
145 }
146 if (n->Opcode() == Op_ShenandoahWriteBarrier) {
147 // tty->print_cr("skipped barrier for chained write barrier object");
148 return false;
149 }
150 if (n->Opcode() == Op_ShenandoahReadBarrier) {
151 if (rb_mem == n->in(Memory)) {
152 // tty->print_cr("Eliminated chained read barrier");
153 return false;
154 } else {
155 return true;
156 }
157 }
158
159 if (n->Opcode() == Op_LoadP ||
160 n->Opcode() == Op_LoadN ||
161 n->Opcode() == Op_GetAndSetP ||
162 n->Opcode() == Op_CompareAndExchangeP ||
163 n->Opcode() == Op_GetAndSetN ||
164 n->Opcode() == Op_CompareAndExchangeN) {
165 return true;
166 }
167 if (n->Opcode() == Op_DecodeN ||
168 n->Opcode() == Op_EncodeP) {
169 return needs_barrier_impl(phase, orig, n->in(1), rb_mem, allow_fromspace, visited);
170 }
171
172 #ifdef ASSERT
173 tty->print("need barrier on?: "); n->dump();
174 ShouldNotReachHere();
175 #endif
176 return true;
177 }
178
179 /**
180 * In Shenandoah, we need barriers on acmp (and similar instructions that compare two
181 * oops) to avoid false negatives. If it compares a from-space and a to-space
182 * copy of an object, a regular acmp would return false, even though both are
183 * the same. The acmp barrier compares the two objects, and when they are
184 * *not equal* it does a read-barrier on both, and compares them again. When it
185 * failed because of different copies of the object, we know that the object
186 * must already have been evacuated (and therefore doesn't require a write-barrier).
187 */
188 void ShenandoahBarrierNode::do_cmpp_if(GraphKit& kit, Node*& taken_branch, Node*& untaken_branch, Node*& taken_memory, Node*& untaken_memory) {
189 assert(taken_memory == NULL && untaken_memory == NULL, "unexpected memory inputs");
190 if (!UseShenandoahGC || !ShenandoahAcmpBarrier || ShenandoahVerifyOptoBarriers) {
191 return;
192 }
193 if (taken_branch->is_top() || untaken_branch->is_top()) {
194 // one of the branches is known to be untaken
195 return;
196 }
197 assert(taken_branch->is_IfProj() && untaken_branch->is_IfProj(), "if projections only");
198 assert(taken_branch->in(0) == untaken_branch->in(0), "should come from same if");
199 IfNode* iff = taken_branch->in(0)->as_If();
200 BoolNode* bol = iff->in(1)->as_Bool();
201 Node* cmp = bol->in(1);
202 if (cmp->Opcode() != Op_CmpP) {
203 return;
204 }
205 Node* a = cmp->in(1);
206 Node* b = cmp->in(2);
207 const Type* a_type = kit.gvn().type(a);
208 const Type* b_type = kit.gvn().type(b);
209 if (a_type->higher_equal(TypePtr::NULL_PTR) || b_type->higher_equal(TypePtr::NULL_PTR)) {
210 // We know one arg is gonna be null. No need for barriers.
211 return;
212 }
213
214 const TypePtr* a_adr_type = ShenandoahBarrierNode::brooks_pointer_type(a_type);
215 const TypePtr* b_adr_type = ShenandoahBarrierNode::brooks_pointer_type(b_type);
216 if ((! ShenandoahBarrierNode::needs_barrier(&kit.gvn(), NULL, a, kit.memory(a_adr_type), false)) &&
217 (! ShenandoahBarrierNode::needs_barrier(&kit.gvn(), NULL, b, kit.memory(b_adr_type), false))) {
218 // We know both args are in to-space already. No acmp barrier needed.
219 return;
220 }
221
222 Node* equal_path = iff->proj_out(true);
223 Node* not_equal_path = iff->proj_out(false);
224
225 if (bol->_test._test == BoolTest::ne) {
226 swap(equal_path, not_equal_path);
227 }
228
229 Node* init_equal_path = equal_path;
230 Node* init_not_equal_path = not_equal_path;
231
232 uint alias_a = kit.C->get_alias_index(a_adr_type);
233 uint alias_b = kit.C->get_alias_index(b_adr_type);
234
235 Node* equal_memory = NULL;
236 Node* not_equal_memory = NULL;
237
238 RegionNode* region = new RegionNode(3);
239 region->init_req(1, equal_path);
240 PhiNode* mem_phi = NULL;
241 if (alias_a == alias_b) {
242 mem_phi = PhiNode::make(region, kit.memory(alias_a), Type::MEMORY, kit.C->get_adr_type(alias_a));
243 } else {
244 Node* mem = kit.reset_memory();
245 mem_phi = PhiNode::make(region, mem, Type::MEMORY, TypePtr::BOTTOM);
246 kit.set_all_memory(mem);
247 }
248
249 kit.set_control(not_equal_path);
250
251 Node* mb = NULL;
252 if (alias_a == alias_b) {
253 Node* mem = kit.reset_memory();
254 mb = MemBarNode::make(kit.C, Op_MemBarAcquire, alias_a);
255 mb->init_req(TypeFunc::Control, kit.control());
256 mb->init_req(TypeFunc::Memory, mem);
257 Node* membar = kit.gvn().transform(mb);
258 kit.set_control(kit.gvn().transform(new ProjNode(membar, TypeFunc::Control)));
259 Node* newmem = kit.gvn().transform(new ProjNode(membar, TypeFunc::Memory));
260 kit.set_all_memory(mem);
261 kit.set_memory(newmem, alias_a);
262 } else {
263 mb = kit.insert_mem_bar(Op_MemBarAcquire);
264 }
265
266 ShenandoahBarrierSetC2* bs = (ShenandoahBarrierSetC2*) BarrierSet::barrier_set()->barrier_set_c2();
267 a = bs->shenandoah_read_barrier_acmp(&kit, a);
268 b = bs->shenandoah_read_barrier_acmp(&kit, b);
269
270 Node* cmp2 = kit.gvn().transform(new CmpPNode(a, b));
271 Node* bol2 = bol->clone();
272 bol2->set_req(1, cmp2);
273 bol2 = kit.gvn().transform(bol2);
274 Node* iff2 = iff->clone();
275 iff2->set_req(0, kit.control());
276 iff2->set_req(1, bol2);
277 kit.gvn().set_type(iff2, kit.gvn().type(iff));
278 Node* equal_path2 = equal_path->clone();
279 equal_path2->set_req(0, iff2);
280 equal_path2 = kit.gvn().transform(equal_path2);
281 Node* not_equal_path2 = not_equal_path->clone();
282 not_equal_path2->set_req(0, iff2);
283 not_equal_path2 = kit.gvn().transform(not_equal_path2);
284
285 region->init_req(2, equal_path2);
286 not_equal_memory = kit.reset_memory();
287 not_equal_path = not_equal_path2;
288
289 kit.set_all_memory(not_equal_memory);
290
291 if (alias_a == alias_b) {
292 mem_phi->init_req(2, kit.memory(alias_a));
293 kit.set_memory(mem_phi, alias_a);
294 } else {
295 mem_phi->init_req(2, kit.reset_memory());
296 }
297
298 kit.record_for_igvn(mem_phi);
299 kit.gvn().set_type(mem_phi, Type::MEMORY);
300
301 if (alias_a == alias_b) {
302 equal_memory = kit.reset_memory();
303 } else {
304 equal_memory = mem_phi;
305 }
306
307 assert(kit.map()->memory() == NULL, "no live memory state");
308 equal_path = kit.gvn().transform(region);
309
310 if (taken_branch == init_equal_path) {
311 assert(untaken_branch == init_not_equal_path, "inconsistent");
312 taken_branch = equal_path;
313 untaken_branch = not_equal_path;
314 taken_memory = equal_memory;
315 untaken_memory = not_equal_memory;
316 } else {
317 assert(taken_branch == init_not_equal_path, "inconsistent");
318 assert(untaken_branch == init_equal_path, "inconsistent");
319 taken_branch = not_equal_path;
320 untaken_branch = equal_path;
321 taken_memory = not_equal_memory;
322 untaken_memory = equal_memory;
323 }
324 }
325
326 bool ShenandoahReadBarrierNode::dominates_memory_rb_impl(PhaseGVN* phase,
327 Node* b1,
328 Node* b2,
329 Node* current,
330 bool linear) {
331 ResourceMark rm;
332 VectorSet visited(Thread::current()->resource_area());
333 Node_Stack phis(0);
334
335 for(int i = 0; i < 10; i++) {
336 if (current == NULL) {
337 return false;
338 } else if (visited.test_set(current->_idx) || current->is_top() || current == b1) {
339 current = NULL;
340 while (phis.is_nonempty() && current == NULL) {
341 uint idx = phis.index();
342 Node* phi = phis.node();
343 if (idx >= phi->req()) {
344 phis.pop();
345 } else {
346 current = phi->in(idx);
347 phis.set_index(idx+1);
348 }
349 }
350 if (current == NULL) {
351 return true;
352 }
353 } else if (current == phase->C->immutable_memory()) {
354 return false;
355 } else if (current->isa_Phi()) {
356 if (!linear) {
357 return false;
358 }
359 phis.push(current, 2);
360 current = current->in(1);
361 } else if (current->Opcode() == Op_ShenandoahWriteBarrier) {
362 const Type* in_type = current->bottom_type();
363 const Type* this_type = b2->bottom_type();
364 if (is_independent(in_type, this_type)) {
365 current = current->in(Memory);
366 } else {
367 return false;
368 }
369 } else if (current->Opcode() == Op_ShenandoahWBMemProj) {
370 current = current->in(0);
371 } else if (current->is_Proj()) {
372 current = current->in(0);
373 } else if (current->is_Call()) {
374 return false; // TODO: Maybe improve by looking at the call's memory effects?
375 } else if (current->is_MemBar()) {
376 return false; // TODO: Do we need to stop at *any* membar?
377 } else if (current->is_MergeMem()) {
378 // if (true) return false;
379 // tty->print_cr("current == mergemem: "); current->dump();
380 const TypePtr* adr_type = brooks_pointer_type(phase->type(b2));
381 uint alias_idx = phase->C->get_alias_index(adr_type);
382 current = current->as_MergeMem()->memory_at(alias_idx);
383 } else {
384 // tty->print_cr("what else can we see here:");
385 #ifdef ASSERT
386 current->dump();
387 #endif
388 ShouldNotReachHere();
389 return false;
390 }
391 }
392 return false;
393 }
394
395 bool ShenandoahReadBarrierNode::is_independent(Node* mem) {
396 if (mem->is_Phi() || mem->is_Proj() || mem->is_MergeMem()) {
397 return true;
398 } else if (mem->Opcode() == Op_ShenandoahWriteBarrier) {
399 const Type* mem_type = mem->bottom_type();
400 const Type* this_type = bottom_type();
401 if (is_independent(mem_type, this_type)) {
402 return true;
403 } else {
404 return false;
405 }
406 } else if (mem->is_Call() || mem->is_MemBar()) {
407 return false;
408 }
409 #ifdef ASSERT
410 mem->dump();
411 #endif
412 ShouldNotReachHere();
413 return true;
414 }
415
416
417 bool ShenandoahReadBarrierNode::dominates_memory_rb(PhaseGVN* phase, Node* b1, Node* b2, bool linear) {
418 return dominates_memory_rb_impl(phase, b1->in(Memory), b2, b2->in(Memory), linear);
419 }
420
421 bool ShenandoahReadBarrierNode::is_independent(const Type* in_type, const Type* this_type) {
422 assert(in_type->isa_oopptr(), "expect oop ptr");
423 assert(this_type->isa_oopptr(), "expect oop ptr");
424 /*
425 if ((! in_type->isa_oopptr()) || (! this_type->isa_oopptr())) {
426 #ifdef ASSERT
427 tty->print_cr("not oopptr");
428 tty->print("in: "); in_type->dump(); tty->print_cr(" ");
429 tty->print("this: "); this_type->dump(); tty->print_cr(" ");
430 #endif
431 return false;
432 }
433 */
434
435 ciKlass* in_kls = in_type->is_oopptr()->klass();
436 ciKlass* this_kls = this_type->is_oopptr()->klass();
437 if (in_kls != NULL && this_kls != NULL &&
438 in_kls->is_loaded() && this_kls->is_loaded() &&
439 (!in_kls->is_subclass_of(this_kls)) &&
440 (!this_kls->is_subclass_of(in_kls))) {
441 #ifdef ASSERT
442 // tty->print_cr("independent: ");
443 // tty->print("in: "); in_kls->print(); tty->print_cr(" ");
444 // tty->print("this: "); this_kls->print(); tty->print_cr(" ");
445 #endif
446 return true;
447 }
448 #ifdef ASSERT
449 // tty->print_cr("possibly dependend?");
450 // tty->print("in: "); in_type->dump(); tty->print_cr(" ");
451 // tty->print("this: "); this_type->dump(); tty->print_cr(" ");
452 #endif
453 return false;
454 }
455
456 Node* ShenandoahReadBarrierNode::Ideal(PhaseGVN *phase, bool can_reshape) {
457
458 if (! can_reshape) {
459 return NULL;
460 }
461
462 if (in(Memory) == phase->C->immutable_memory()) return NULL;
463
464 // If memory input is a MergeMem, take the appropriate slice out of it.
465 Node* mem_in = in(Memory);
466 if (mem_in->isa_MergeMem()) {
467 const TypePtr* adr_type = brooks_pointer_type(bottom_type());
468 uint alias_idx = phase->C->get_alias_index(adr_type);
469 mem_in = mem_in->as_MergeMem()->memory_at(alias_idx);
470 set_req(Memory, mem_in);
471 return this;
472 }
473
474 Node* input = in(Memory);
475 if (input->Opcode() == Op_ShenandoahWBMemProj) {
476 Node* wb = input->in(0);
477 const Type* in_type = phase->type(wb);
478 // is_top() test not sufficient here: we can come here after CCP
479 // in a dead branch of the graph that has not yet been removed.
480 if (in_type == Type::TOP) return NULL; // Dead path.
481 assert(wb->Opcode() == Op_ShenandoahWriteBarrier, "expect write barrier");
482 if (is_independent(in_type, _type)) {
483 phase->igvn_rehash_node_delayed(wb);
484 set_req(Memory, wb->in(Memory));
485 if (can_reshape && input->outcnt() == 0) {
486 phase->is_IterGVN()->_worklist.push(input);
487 }
488 return this;
489 }
490 }
491 return NULL;
492 }
493
494 ShenandoahWriteBarrierNode::ShenandoahWriteBarrierNode(Compile* C, Node* ctrl, Node* mem, Node* obj)
495 : ShenandoahBarrierNode(ctrl, mem, obj, false) {
496 assert(UseShenandoahGC && ShenandoahWriteBarrier, "should be enabled");
497 ShenandoahBarrierSetC2::bsc2()->state()->add_shenandoah_barrier(this);
498 }
499
500 Node* ShenandoahWriteBarrierNode::Identity(PhaseGVN* phase) {
501 assert(in(0) != NULL, "should have control");
502 PhaseIterGVN* igvn = phase->is_IterGVN();
503 Node* mem_in = in(Memory);
504 Node* mem_proj = NULL;
505
506 if (igvn != NULL) {
507 mem_proj = find_out_with(Op_ShenandoahWBMemProj);
508 if (mem_proj == NULL || mem_in == mem_proj) {
509 return this;
510 }
511 }
512
513 Node* replacement = Identity_impl(phase);
514 if (igvn != NULL) {
515 if (replacement != NULL && replacement != this) {
516 igvn->replace_node(mem_proj, mem_in);
517 }
518 }
519 return replacement;
520 }
521
522
523 Node* ShenandoahWriteBarrierNode::Ideal(PhaseGVN *phase, bool can_reshape) {
524 assert(in(0) != NULL, "should have control");
525 if (!can_reshape) {
526 return NULL;
527 }
528
529 PhaseIterGVN* igvn = phase->is_IterGVN();
530 Node* mem_proj = find_out_with(Op_ShenandoahWBMemProj);
531 Node* mem_in = in(Memory);
532
533 if (mem_in == phase->C->immutable_memory()) return NULL;
534
535 if (mem_in->isa_MergeMem()) {
536 const TypePtr* adr_type = brooks_pointer_type(bottom_type());
537 uint alias_idx = phase->C->get_alias_index(adr_type);
538 mem_in = mem_in->as_MergeMem()->memory_at(alias_idx);
539 set_req(Memory, mem_in);
540 return this;
541 }
542
543 return NULL;
544 }
545
546 bool ShenandoahWriteBarrierNode::expand(Compile* C, PhaseIterGVN& igvn, int& loop_opts_cnt) {
547 if (UseShenandoahGC && ShenandoahWriteBarrierToIR) {
548 if (ShenandoahBarrierSetC2::bsc2()->state()->shenandoah_barriers_count() > 0) {
549 bool attempt_more_loopopts = ShenandoahLoopOptsAfterExpansion;
550 C->clear_major_progress();
551 PhaseIdealLoop ideal_loop(igvn, LoopOptsShenandoahExpand);
552 if (C->failing()) return false;
553 PhaseIdealLoop::verify(igvn);
554 DEBUG_ONLY(ShenandoahBarrierNode::verify_raw_mem(C->root());)
555 if (attempt_more_loopopts) {
556 C->set_major_progress();
557 if (!C->optimize_loops(loop_opts_cnt, igvn, LoopOptsShenandoahPostExpand)) {
558 return false;
559 }
560 C->clear_major_progress();
561 }
562 }
563 }
564 return true;
565 }
566
567 bool ShenandoahWriteBarrierNode::is_heap_state_test(Node* iff, int mask) {
568 if (!UseShenandoahGC) {
569 return false;
570 }
571 assert(iff->is_If(), "bad input");
572 if (iff->Opcode() != Op_If) {
573 return false;
574 }
575 Node* bol = iff->in(1);
576 if (!bol->is_Bool() || bol->as_Bool()->_test._test != BoolTest::ne) {
577 return false;
578 }
579 Node* cmp = bol->in(1);
580 if (cmp->Opcode() != Op_CmpI) {
581 return false;
582 }
583 Node* in1 = cmp->in(1);
584 Node* in2 = cmp->in(2);
585 if (in2->find_int_con(-1) != 0) {
586 return false;
587 }
588 if (in1->Opcode() != Op_AndI) {
589 return false;
590 }
591 in2 = in1->in(2);
592 if (in2->find_int_con(-1) != mask) {
593 return false;
594 }
595 in1 = in1->in(1);
596
597 return is_gc_state_load(in1);
598 }
599
600
601 bool ShenandoahWriteBarrierNode::is_evacuation_in_progress_test(Node* iff) {
602 return is_heap_state_test(iff, ShenandoahHeap::EVACUATION | ShenandoahHeap::TRAVERSAL);
603 }
604
605 bool ShenandoahWriteBarrierNode::is_heap_stable_test(Node* iff) {
606 if (!UseShenandoahGC) {
607 return false;
608 }
609 assert(iff->is_If(), "bad input");
610 if (iff->Opcode() != Op_If) {
611 return false;
612 }
613 Node* bol = iff->in(1);
614 if (bol == NULL || !bol->is_Bool() || bol->as_Bool()->_test._test != BoolTest::ne) {
615 return false;
616 }
617 Node* cmp = bol->in(1);
618 if (cmp->Opcode() != Op_CmpI) {
619 return false;
620 }
621 Node* in1 = cmp->in(1);
622 Node* in2 = cmp->in(2);
623 if (in2->find_int_con(-1) != 0) {
624 return false;
625 }
626 return is_gc_state_load(in1);
627 }
628
629 bool ShenandoahWriteBarrierNode::is_gc_state_load(Node *n) {
630 if (!UseShenandoahGC) {
631 return false;
632 }
633 if (n->Opcode() != Op_LoadB) {
634 return false;
635 }
636 Node* addp = n->in(MemNode::Address);
637 if (!addp->is_AddP()) {
638 return false;
639 }
640 Node* base = addp->in(AddPNode::Address);
641 Node* off = addp->in(AddPNode::Offset);
642 if (base->Opcode() != Op_ThreadLocal) {
643 return false;
644 }
645 if (off->find_intptr_t_con(-1) != in_bytes(ShenandoahThreadLocalData::gc_state_offset())) {
646 return false;
647 }
648 return true;
649 }
650
651 bool ShenandoahWriteBarrierNode::has_safepoint_between(Node* start, Node* stop, PhaseIdealLoop *phase) {
652 assert(phase->is_dominator(stop, start), "bad inputs");
653 ResourceMark rm;
654 Unique_Node_List wq;
655 wq.push(start);
656 for (uint next = 0; next < wq.size(); next++) {
657 Node *m = wq.at(next);
658 if (m == stop) {
659 continue;
660 }
661 if (m->is_SafePoint() && !m->is_CallLeaf()) {
662 return true;
663 }
664 if (m->is_Region()) {
665 for (uint i = 1; i < m->req(); i++) {
666 wq.push(m->in(i));
667 }
668 } else {
669 wq.push(m->in(0));
670 }
671 }
672 return false;
673 }
674
675 bool ShenandoahWriteBarrierNode::try_common_gc_state_load(Node *n, PhaseIdealLoop *phase) {
676 assert(is_gc_state_load(n), "inconsistent");
677 Node* addp = n->in(MemNode::Address);
678 Node* dominator = NULL;
679 for (DUIterator_Fast imax, i = addp->fast_outs(imax); i < imax; i++) {
680 Node* u = addp->fast_out(i);
681 assert(is_gc_state_load(u), "inconsistent");
682 if (u != n && phase->is_dominator(u->in(0), n->in(0))) {
683 if (dominator == NULL) {
684 dominator = u;
685 } else {
686 if (phase->dom_depth(u->in(0)) < phase->dom_depth(dominator->in(0))) {
687 dominator = u;
688 }
689 }
690 }
691 }
692 if (dominator == NULL || has_safepoint_between(n->in(0), dominator->in(0), phase)) {
693 return false;
694 }
695 phase->igvn().replace_node(n, dominator);
696
697 return true;
698 }
699
700 Node* ShenandoahWriteBarrierNode::evacuation_in_progress_test_ctrl(Node* iff) {
701 assert(is_evacuation_in_progress_test(iff), "bad input");
702 return iff->in(0);
703 }
704
705 bool ShenandoahBarrierNode::dominates_memory_impl(PhaseGVN* phase,
706 Node* b1,
707 Node* b2,
708 Node* current,
709 bool linear) {
710 ResourceMark rm;
711 VectorSet visited(Thread::current()->resource_area());
712 Node_Stack phis(0);
713
714
715 for(int i = 0; i < 10; i++) {
716 if (current == NULL) {
717 return false;
718 } else if (visited.test_set(current->_idx) || current->is_top() || current == b1) {
719 current = NULL;
720 while (phis.is_nonempty() && current == NULL) {
721 uint idx = phis.index();
722 Node* phi = phis.node();
723 if (idx >= phi->req()) {
724 phis.pop();
725 } else {
726 current = phi->in(idx);
727 phis.set_index(idx+1);
728 }
729 }
730 if (current == NULL) {
731 return true;
732 }
733 } else if (current == b2) {
734 return false;
735 } else if (current == phase->C->immutable_memory()) {
736 return false;
737 } else if (current->isa_Phi()) {
738 if (!linear) {
739 return false;
740 }
741 phis.push(current, 2);
742 current = current->in(1);
743 } else if (current->Opcode() == Op_ShenandoahWriteBarrier) {
744 current = current->in(Memory);
745 } else if (current->Opcode() == Op_ShenandoahWBMemProj) {
746 current = current->in(0);
747 } else if (current->is_Proj()) {
748 current = current->in(0);
749 } else if (current->is_Call()) {
750 current = current->in(TypeFunc::Memory);
751 } else if (current->is_MemBar()) {
752 current = current->in(TypeFunc::Memory);
753 } else if (current->is_MergeMem()) {
754 const TypePtr* adr_type = brooks_pointer_type(phase->type(b2));
755 uint alias_idx = phase->C->get_alias_index(adr_type);
756 current = current->as_MergeMem()->memory_at(alias_idx);
757 } else {
758 #ifdef ASSERT
759 current->dump();
760 #endif
761 ShouldNotReachHere();
762 return false;
763 }
764 }
765 return false;
766 }
767
768 /**
769 * Determines if b1 dominates b2 through memory inputs. It returns true if:
770 * - b1 can be reached by following each branch in b2's memory input (through phis, etc)
771 * - or we get back to b2 (i.e. through a loop) without seeing b1
772 * In all other cases, (in particular, if we reach immutable_memory without having seen b1)
773 * we return false.
774 */
775 bool ShenandoahBarrierNode::dominates_memory(PhaseGVN* phase, Node* b1, Node* b2, bool linear) {
776 return dominates_memory_impl(phase, b1, b2, b2->in(Memory), linear);
777 }
778
779 Node* ShenandoahBarrierNode::Identity_impl(PhaseGVN* phase) {
780 Node* n = in(ValueIn);
781
782 Node* rb_mem = Opcode() == Op_ShenandoahReadBarrier ? in(Memory) : NULL;
783 if (! needs_barrier(phase, this, n, rb_mem, _allow_fromspace)) {
784 return n;
785 }
786
787 // tty->print_cr("find sibling for: "); dump(2);
788 // Try to find a write barrier sibling with identical inputs that we can fold into.
789 for (DUIterator i = n->outs(); n->has_out(i); i++) {
790 Node* sibling = n->out(i);
791 if (sibling == this) {
792 continue;
793 }
794 /*
795 assert(sibling->Opcode() != Op_ShenandoahWriteBarrier ||
796 Opcode() != Op_ShenandoahWriteBarrier || hash() == sibling->hash(),
797 "if this is a write barrier, then sibling can't be write barrier too");
798 */
799 if (sibling->Opcode() != Op_ShenandoahWriteBarrier) {
800 continue;
801 }
802 /*
803 if (sibling->outcnt() == 0) {
804 // Some dead node.
805 continue;
806 }
807 */
808 assert(sibling->in(ValueIn) == in(ValueIn), "sanity");
809 assert(sibling->Opcode() == Op_ShenandoahWriteBarrier, "sanity");
810 // tty->print_cr("candidate: "); sibling->dump();
811
812 if (dominates_memory(phase, sibling, this, phase->is_IterGVN() == NULL)) {
813
814 /*
815 tty->print_cr("matched barrier:");
816 sibling->dump();
817 tty->print_cr("for: ");
818 dump();
819 */
820 return sibling;
821 }
822
823 /*
824 tty->print_cr("couldn't match candidate:");
825 sibling->dump(2);
826 */
827 }
828 /*
829 tty->print_cr("couldn't match barrier to any:");
830 dump();
831 */
832 return this;
833 }
834
835 #ifndef PRODUCT
836 void ShenandoahBarrierNode::dump_spec(outputStream *st) const {
837 const TypePtr* adr = adr_type();
838 if (adr == NULL) {
839 return;
840 }
841 st->print(" @");
842 adr->dump_on(st);
843 st->print(" (");
844 Compile::current()->alias_type(adr)->adr_type()->dump_on(st);
845 st->print(") ");
846 }
847 #endif
848
849 Node* ShenandoahReadBarrierNode::Identity(PhaseGVN* phase) {
850
851 // if (true) return this;
852
853 // tty->print("optimizing rb: "); dump();
854 Node* id = Identity_impl(phase);
855
856 if (id == this && phase->is_IterGVN()) {
857 Node* n = in(ValueIn);
858 // No success in super call. Try to combine identical read barriers.
859 for (DUIterator i = n->outs(); n->has_out(i); i++) {
860 Node* sibling = n->out(i);
861 if (sibling == this || sibling->Opcode() != Op_ShenandoahReadBarrier) {
862 continue;
863 }
864 assert(sibling->in(ValueIn) == in(ValueIn), "sanity");
865 if (phase->is_IterGVN()->hash_find(sibling) &&
866 sibling->bottom_type() == bottom_type() &&
867 sibling->in(Control) == in(Control) &&
868 dominates_memory_rb(phase, sibling, this, phase->is_IterGVN() == NULL)) {
869 /*
870 if (in(Memory) != sibling->in(Memory)) {
871 tty->print_cr("interesting rb-fold");
872 dump();
873 sibling->dump();
874 }
875 */
876 return sibling;
877 }
878 }
879 }
880 return id;
881 }
882
883 const Type* ShenandoahBarrierNode::Value(PhaseGVN* phase) const {
884 // Either input is TOP ==> the result is TOP
885 const Type *t1 = phase->type(in(Memory));
886 if (t1 == Type::TOP) return Type::TOP;
887 const Type *t2 = phase->type(in(ValueIn));
888 if( t2 == Type::TOP ) return Type::TOP;
889
890 Node* input = in(ValueIn);
891 const Type* type = phase->type(input)->is_oopptr()->cast_to_nonconst();
892 return type;
893 }
894
895 uint ShenandoahBarrierNode::hash() const {
896 return TypeNode::hash() + _allow_fromspace;
897 }
898
899 uint ShenandoahBarrierNode::cmp(const Node& n) const {
900 return _allow_fromspace == ((ShenandoahBarrierNode&) n)._allow_fromspace
901 && TypeNode::cmp(n);
902 }
903
904 uint ShenandoahBarrierNode::size_of() const {
905 return sizeof(*this);
906 }
907
908 Node* ShenandoahWBMemProjNode::Identity(PhaseGVN* phase) {
909
910 Node* wb = in(0);
911 if (wb->is_top()) return phase->C->top(); // Dead path.
912
913 assert(wb->Opcode() == Op_ShenandoahWriteBarrier, "expect write barrier");
914 PhaseIterGVN* igvn = phase->is_IterGVN();
915 // We can't do the below unless the graph is fully constructed.
916 if (igvn == NULL) {
917 return this;
918 }
919
920 // If the mem projection has no barrier users, it's not needed anymore.
921 Unique_Node_List visited;
922 if (wb->outcnt() == 1) {
923 return wb->in(ShenandoahBarrierNode::Memory);
924 }
925
926 return this;
927 }
928
929 #ifdef ASSERT
930 bool ShenandoahBarrierNode::verify_helper(Node* in, Node_Stack& phis, VectorSet& visited, verify_type t, bool trace, Unique_Node_List& barriers_used) {
931 assert(phis.size() == 0, "");
932
933 while (true) {
934 if (!in->bottom_type()->make_ptr()->make_oopptr()) {
935 if (trace) {tty->print_cr("Non oop");}
936 } else if (t == ShenandoahLoad && ShenandoahOptimizeStableFinals &&
937 in->bottom_type()->make_ptr()->isa_aryptr() &&
938 in->bottom_type()->make_ptr()->is_aryptr()->is_stable()) {
939 if (trace) {tty->print_cr("Stable array load");}
940 } else {
941 if (in->is_ConstraintCast()) {
942 in = in->in(1);
943 continue;
944 } else if (in->is_AddP()) {
945 assert(!in->in(AddPNode::Address)->is_top(), "no raw memory access");
946 in = in->in(AddPNode::Address);
947 continue;
948 } else if (in->is_Con() && !ShenandoahBarriersForConst) {
949 if (trace) {tty->print("Found constant"); in->dump();}
950 } else if (in->is_ShenandoahBarrier()) {
951 if (t == ShenandoahStore && in->Opcode() != Op_ShenandoahWriteBarrier) {
952 return false;
953 }
954 barriers_used.push(in);
955 if (trace) {tty->print("Found barrier"); in->dump();}
956 } else if (in->is_Proj() && in->in(0)->is_Allocate()) {
957 if (trace) {tty->print("Found alloc"); in->in(0)->dump();}
958 } else if (in->is_Phi()) {
959 if (!visited.test_set(in->_idx)) {
960 if (trace) {tty->print("Pushed phi:"); in->dump();}
961 phis.push(in, 2);
962 in = in->in(1);
963 continue;
964 }
965 if (trace) {tty->print("Already seen phi:"); in->dump();}
966 } else if (in->Opcode() == Op_CMoveP || in->Opcode() == Op_CMoveN) {
967 if (!visited.test_set(in->_idx)) {
968 if (trace) {tty->print("Pushed cmovep:"); in->dump();}
969 phis.push(in, CMoveNode::IfTrue);
970 in = in->in(CMoveNode::IfFalse);
971 continue;
972 }
973 if (trace) {tty->print("Already seen cmovep:"); in->dump();}
974 } else if (in->Opcode() == Op_EncodeP || in->Opcode() == Op_DecodeN) {
975 in = in->in(1);
976 continue;
977 } else {
978 return false;
979 }
980 }
981 bool cont = false;
982 while (phis.is_nonempty()) {
983 uint idx = phis.index();
984 Node* phi = phis.node();
985 if (idx >= phi->req()) {
986 if (trace) {tty->print("Popped phi:"); phi->dump();}
987 phis.pop();
988 continue;
989 }
990 if (trace) {tty->print("Next entry(%d) for phi:", idx); phi->dump();}
991 in = phi->in(idx);
992 phis.set_index(idx+1);
993 cont = true;
994 break;
995 }
996 if (!cont) {
997 break;
998 }
999 }
1000 return true;
1001 }
1002
1003 void ShenandoahBarrierNode::report_verify_failure(const char *msg, Node *n1, Node *n2) {
1004 if (n1 != NULL) {
1005 n1->dump(+10);
1006 }
1007 if (n2 != NULL) {
1008 n2->dump(+10);
1009 }
1010 fatal("%s", msg);
1011 }
1012
1013 void ShenandoahBarrierNode::verify(RootNode* root) {
1014 ResourceMark rm;
1015 Unique_Node_List wq;
1016 GrowableArray<Node*> barriers;
1017 Unique_Node_List barriers_used;
1018 Node_Stack phis(0);
1019 VectorSet visited(Thread::current()->resource_area());
1020 const bool trace = false;
1021 const bool verify_no_useless_barrier = false;
1022
1023 wq.push(root);
1024 for (uint next = 0; next < wq.size(); next++) {
1025 Node *n = wq.at(next);
1026 if (n->is_Load()) {
1027 const bool trace = false;
1028 if (trace) {tty->print("Verifying"); n->dump();}
1029 if (n->Opcode() == Op_LoadRange || n->Opcode() == Op_LoadKlass || n->Opcode() == Op_LoadNKlass) {
1030 if (trace) {tty->print_cr("Load range/klass");}
1031 } else {
1032 const TypePtr* adr_type = n->as_Load()->adr_type();
1033
1034 if (adr_type->isa_oopptr() && adr_type->is_oopptr()->offset() == oopDesc::mark_offset_in_bytes()) {
1035 if (trace) {tty->print_cr("Mark load");}
1036 } else if (adr_type->isa_instptr() &&
1037 adr_type->is_instptr()->klass()->is_subtype_of(Compile::current()->env()->Reference_klass()) &&
1038 adr_type->is_instptr()->offset() == java_lang_ref_Reference::referent_offset) {
1039 if (trace) {tty->print_cr("Reference.get()");}
1040 } else {
1041 bool verify = true;
1042 if (adr_type->isa_instptr()) {
1043 const TypeInstPtr* tinst = adr_type->is_instptr();
1044 ciKlass* k = tinst->klass();
1045 assert(k->is_instance_klass(), "");
1046 ciInstanceKlass* ik = (ciInstanceKlass*)k;
1047 int offset = adr_type->offset();
1048
1049 if ((ik->debug_final_field_at(offset) && ShenandoahOptimizeInstanceFinals) ||
1050 (ik->debug_stable_field_at(offset) && ShenandoahOptimizeStableFinals)) {
1051 if (trace) {tty->print_cr("Final/stable");}
1052 verify = false;
1053 } else if (k == ciEnv::current()->Class_klass() &&
1054 tinst->const_oop() != NULL &&
1055 tinst->offset() >= (ik->size_helper() * wordSize)) {
1056 ciInstanceKlass* k = tinst->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
1057 ciField* field = k->get_field_by_offset(tinst->offset(), true);
1058 if ((ShenandoahOptimizeStaticFinals && field->is_final()) ||
1059 (ShenandoahOptimizeStableFinals && field->is_stable())) {
1060 verify = false;
1061 }
1062 }
1063 }
1064
1065 if (verify && !ShenandoahBarrierNode::verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahLoad, trace, barriers_used)) {
1066 report_verify_failure("Shenandoah verification: Load should have barriers", n);
1067 }
1068 }
1069 }
1070 } else if (n->is_Store()) {
1071 const bool trace = false;
1072
1073 if (trace) {tty->print("Verifying"); n->dump();}
1074 if (n->in(MemNode::ValueIn)->bottom_type()->make_oopptr()) {
1075 Node* adr = n->in(MemNode::Address);
1076 bool verify = true;
1077
1078 if (adr->is_AddP() && adr->in(AddPNode::Base)->is_top()) {
1079 adr = adr->in(AddPNode::Address);
1080 if (adr->is_AddP()) {
1081 assert(adr->in(AddPNode::Base)->is_top(), "");
1082 adr = adr->in(AddPNode::Address);
1083 if (adr->Opcode() == Op_LoadP &&
1084 adr->in(MemNode::Address)->in(AddPNode::Base)->is_top() &&
1085 adr->in(MemNode::Address)->in(AddPNode::Address)->Opcode() == Op_ThreadLocal &&
1086 adr->in(MemNode::Address)->in(AddPNode::Offset)->find_intptr_t_con(-1) == in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset())) {
1087 if (trace) {tty->print_cr("SATB prebarrier");}
1088 verify = false;
1089 }
1090 }
1091 }
1092
1093 if (verify && !ShenandoahBarrierNode::verify_helper(n->in(MemNode::ValueIn), phis, visited, ShenandoahValue, trace, barriers_used)) {
1094 report_verify_failure("Shenandoah verification: Store should have barriers", n);
1095 }
1096 }
1097 if (!ShenandoahBarrierNode::verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahStore, trace, barriers_used)) {
1098 report_verify_failure("Shenandoah verification: Store (address) should have barriers", n);
1099 }
1100 } else if (n->Opcode() == Op_CmpP) {
1101 const bool trace = false;
1102
1103 Node* in1 = n->in(1);
1104 Node* in2 = n->in(2);
1105 if (in1->bottom_type()->isa_oopptr()) {
1106 if (trace) {tty->print("Verifying"); n->dump();}
1107
1108 bool mark_inputs = false;
1109 if (in1->bottom_type() == TypePtr::NULL_PTR || in2->bottom_type() == TypePtr::NULL_PTR ||
1110 ((in1->is_Con() || in2->is_Con()) && !ShenandoahBarriersForConst)) {
1111 if (trace) {tty->print_cr("Comparison against a constant");}
1112 mark_inputs = true;
1113 } else if ((in1->is_CheckCastPP() && in1->in(1)->is_Proj() && in1->in(1)->in(0)->is_Allocate()) ||
1114 (in2->is_CheckCastPP() && in2->in(1)->is_Proj() && in2->in(1)->in(0)->is_Allocate())) {
1115 if (trace) {tty->print_cr("Comparison with newly alloc'ed object");}
1116 mark_inputs = true;
1117 } else {
1118 assert(in2->bottom_type()->isa_oopptr(), "");
1119
1120 if (!ShenandoahBarrierNode::verify_helper(in1, phis, visited, ShenandoahStore, trace, barriers_used) ||
1121 !ShenandoahBarrierNode::verify_helper(in2, phis, visited, ShenandoahStore, trace, barriers_used)) {
1122 report_verify_failure("Shenandoah verification: Cmp should have barriers", n);
1123 }
1124 }
1125 if (verify_no_useless_barrier &&
1126 mark_inputs &&
1127 (!ShenandoahBarrierNode::verify_helper(in1, phis, visited, ShenandoahValue, trace, barriers_used) ||
1128 !ShenandoahBarrierNode::verify_helper(in2, phis, visited, ShenandoahValue, trace, barriers_used))) {
1129 phis.clear();
1130 visited.Reset();
1131 }
1132 }
1133 } else if (n->is_LoadStore()) {
1134 if (n->in(MemNode::ValueIn)->bottom_type()->isa_ptr() &&
1135 !ShenandoahBarrierNode::verify_helper(n->in(MemNode::ValueIn), phis, visited, ShenandoahLoad, trace, barriers_used)) {
1136 report_verify_failure("Shenandoah verification: LoadStore (value) should have barriers", n);
1137 }
1138
1139 if (n->in(MemNode::Address)->bottom_type()->isa_oopptr() && !ShenandoahBarrierNode::verify_helper(n->in(MemNode::Address), phis, visited, ShenandoahStore, trace, barriers_used)) {
1140 report_verify_failure("Shenandoah verification: LoadStore (address) should have barriers", n);
1141 }
1142 } else if (n->Opcode() == Op_CallLeafNoFP || n->Opcode() == Op_CallLeaf) {
1143 CallNode* call = n->as_Call();
1144
1145 static struct {
1146 const char* name;
1147 struct {
1148 int pos;
1149 verify_type t;
1150 } args[6];
1151 } calls[] = {
1152 "aescrypt_encryptBlock",
1153 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
1154 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1155 "aescrypt_decryptBlock",
1156 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
1157 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1158 "multiplyToLen",
1159 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad }, { TypeFunc::Parms+4, ShenandoahStore },
1160 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1161 "squareToLen",
1162 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad }, { -1, ShenandoahNone},
1163 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1164 "montgomery_multiply",
1165 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad },
1166 { TypeFunc::Parms+6, ShenandoahStore }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1167 "montgomery_square",
1168 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+5, ShenandoahStore },
1169 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1170 "mulAdd",
1171 { { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone},
1172 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1173 "vectorizedMismatch",
1174 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone},
1175 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1176 "updateBytesCRC32",
1177 { { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
1178 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1179 "updateBytesAdler32",
1180 { { TypeFunc::Parms+1, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
1181 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1182 "updateBytesCRC32C",
1183 { { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+3, ShenandoahLoad}, { -1, ShenandoahNone},
1184 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1185 "counterMode_AESCrypt",
1186 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
1187 { TypeFunc::Parms+3, ShenandoahStore }, { TypeFunc::Parms+5, ShenandoahStore }, { TypeFunc::Parms+6, ShenandoahStore } },
1188 "cipherBlockChaining_encryptAESCrypt",
1189 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
1190 { TypeFunc::Parms+3, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1191 "cipherBlockChaining_decryptAESCrypt",
1192 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { TypeFunc::Parms+2, ShenandoahLoad },
1193 { TypeFunc::Parms+3, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1194 "shenandoah_clone_barrier",
1195 { { TypeFunc::Parms, ShenandoahLoad }, { -1, ShenandoahNone}, { -1, ShenandoahNone},
1196 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1197 "ghash_processBlocks",
1198 { { TypeFunc::Parms, ShenandoahStore }, { TypeFunc::Parms+1, ShenandoahLoad }, { TypeFunc::Parms+2, ShenandoahLoad },
1199 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1200 "sha1_implCompress",
1201 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
1202 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1203 "sha256_implCompress",
1204 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
1205 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1206 "sha512_implCompress",
1207 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
1208 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1209 "sha1_implCompressMB",
1210 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
1211 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1212 "sha256_implCompressMB",
1213 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
1214 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1215 "sha512_implCompressMB",
1216 { { TypeFunc::Parms, ShenandoahLoad }, { TypeFunc::Parms+1, ShenandoahStore }, { -1, ShenandoahNone },
1217 { -1, ShenandoahNone}, { -1, ShenandoahNone}, { -1, ShenandoahNone} },
1218 };
1219
1220 if (call->is_call_to_arraycopystub()) {
1221 Node* dest = NULL;
1222 const TypeTuple* args = n->as_Call()->_tf->domain();
1223 for (uint i = TypeFunc::Parms, j = 0; i < args->cnt(); i++) {
1224 if (args->field_at(i)->isa_ptr()) {
1225 j++;
1226 if (j == 2) {
1227 dest = n->in(i);
1228 break;
1229 }
1230 }
1231 }
1232 if (!ShenandoahBarrierNode::verify_helper(n->in(TypeFunc::Parms), phis, visited, ShenandoahLoad, trace, barriers_used) ||
1233 !ShenandoahBarrierNode::verify_helper(dest, phis, visited, ShenandoahStore, trace, barriers_used)) {
1234 report_verify_failure("Shenandoah verification: ArrayCopy should have barriers", n);
1235 }
1236 } else if (strlen(call->_name) > 5 &&
1237 !strcmp(call->_name + strlen(call->_name) - 5, "_fill")) {
1238 if (!ShenandoahBarrierNode::verify_helper(n->in(TypeFunc::Parms), phis, visited, ShenandoahStore, trace, barriers_used)) {
1239 report_verify_failure("Shenandoah verification: _fill should have barriers", n);
1240 }
1241 } else if (!strcmp(call->_name, "shenandoah_wb_pre")) {
1242 // skip
1243 } else {
1244 const int calls_len = sizeof(calls) / sizeof(calls[0]);
1245 int i = 0;
1246 for (; i < calls_len; i++) {
1247 if (!strcmp(calls[i].name, call->_name)) {
1248 break;
1249 }
1250 }
1251 if (i != calls_len) {
1252 const uint args_len = sizeof(calls[0].args) / sizeof(calls[0].args[0]);
1253 for (uint j = 0; j < args_len; j++) {
1254 int pos = calls[i].args[j].pos;
1255 if (pos == -1) {
1256 break;
1257 }
1258 if (!ShenandoahBarrierNode::verify_helper(call->in(pos), phis, visited, calls[i].args[j].t, trace, barriers_used)) {
1259 report_verify_failure("Shenandoah verification: intrinsic calls should have barriers", n);
1260 }
1261 }
1262 for (uint j = TypeFunc::Parms; j < call->req(); j++) {
1263 if (call->in(j)->bottom_type()->make_ptr() &&
1264 call->in(j)->bottom_type()->make_ptr()->isa_oopptr()) {
1265 uint k = 0;
1266 for (; k < args_len && calls[i].args[k].pos != (int)j; k++);
1267 if (k == args_len) {
1268 fatal("arg %d for call %s not covered", j, call->_name);
1269 }
1270 }
1271 }
1272 } else {
1273 for (uint j = TypeFunc::Parms; j < call->req(); j++) {
1274 if (call->in(j)->bottom_type()->make_ptr() &&
1275 call->in(j)->bottom_type()->make_ptr()->isa_oopptr()) {
1276 fatal("%s not covered", call->_name);
1277 }
1278 }
1279 }
1280 }
1281 } else if (n->is_ShenandoahBarrier()) {
1282 assert(!barriers.contains(n), "");
1283 assert(n->Opcode() != Op_ShenandoahWriteBarrier || n->find_out_with(Op_ShenandoahWBMemProj) != NULL, "bad shenandoah write barrier");
1284 assert(n->Opcode() != Op_ShenandoahWriteBarrier || n->outcnt() > 1, "bad shenandoah write barrier");
1285 barriers.push(n);
1286 } else if (n->is_AddP()
1287 || n->is_Phi()
1288 || n->is_ConstraintCast()
1289 || n->Opcode() == Op_Return
1290 || n->Opcode() == Op_CMoveP
1291 || n->Opcode() == Op_CMoveN
1292 || n->Opcode() == Op_Rethrow
1293 || n->is_MemBar()
1294 || n->Opcode() == Op_Conv2B
1295 || n->Opcode() == Op_SafePoint
1296 || n->is_CallJava()
1297 || n->Opcode() == Op_Unlock
1298 || n->Opcode() == Op_EncodeP
1299 || n->Opcode() == Op_DecodeN) {
1300 // nothing to do
1301 } else {
1302 static struct {
1303 int opcode;
1304 struct {
1305 int pos;
1306 verify_type t;
1307 } inputs[2];
1308 } others[] = {
1309 Op_FastLock,
1310 { { 1, ShenandoahLoad }, { -1, ShenandoahNone} },
1311 Op_Lock,
1312 { { TypeFunc::Parms, ShenandoahLoad }, { -1, ShenandoahNone} },
1313 Op_ArrayCopy,
1314 { { ArrayCopyNode::Src, ShenandoahLoad }, { ArrayCopyNode::Dest, ShenandoahStore } },
1315 Op_StrCompressedCopy,
1316 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
1317 Op_StrInflatedCopy,
1318 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
1319 Op_AryEq,
1320 { { 2, ShenandoahLoad }, { 3, ShenandoahLoad } },
1321 Op_StrIndexOf,
1322 { { 2, ShenandoahLoad }, { 4, ShenandoahLoad } },
1323 Op_StrComp,
1324 { { 2, ShenandoahLoad }, { 4, ShenandoahLoad } },
1325 Op_StrEquals,
1326 { { 2, ShenandoahLoad }, { 3, ShenandoahLoad } },
1327 Op_EncodeISOArray,
1328 { { 2, ShenandoahLoad }, { 3, ShenandoahStore } },
1329 Op_HasNegatives,
1330 { { 2, ShenandoahLoad }, { -1, ShenandoahNone} },
1331 Op_CastP2X,
1332 { { 1, ShenandoahLoad }, { -1, ShenandoahNone} },
1333 Op_StrIndexOfChar,
1334 { { 2, ShenandoahLoad }, { -1, ShenandoahNone } },
1335 };
1336
1337 const int others_len = sizeof(others) / sizeof(others[0]);
1338 int i = 0;
1339 for (; i < others_len; i++) {
1340 if (others[i].opcode == n->Opcode()) {
1341 break;
1342 }
1343 }
1344 uint stop = n->is_Call() ? n->as_Call()->tf()->domain()->cnt() : n->req();
1345 if (i != others_len) {
1346 const uint inputs_len = sizeof(others[0].inputs) / sizeof(others[0].inputs[0]);
1347 for (uint j = 0; j < inputs_len; j++) {
1348 int pos = others[i].inputs[j].pos;
1349 if (pos == -1) {
1350 break;
1351 }
1352 if (!ShenandoahBarrierNode::verify_helper(n->in(pos), phis, visited, others[i].inputs[j].t, trace, barriers_used)) {
1353 report_verify_failure("Shenandoah verification: intrinsic calls should have barriers", n);
1354 }
1355 }
1356 for (uint j = 1; j < stop; j++) {
1357 if (n->in(j) != NULL && n->in(j)->bottom_type()->make_ptr() &&
1358 n->in(j)->bottom_type()->make_ptr()->make_oopptr()) {
1359 uint k = 0;
1360 for (; k < inputs_len && others[i].inputs[k].pos != (int)j; k++);
1361 if (k == inputs_len) {
1362 fatal("arg %d for node %s not covered", j, n->Name());
1363 }
1364 }
1365 }
1366 } else {
1367 for (uint j = 1; j < stop; j++) {
1368 if (n->in(j) != NULL && n->in(j)->bottom_type()->make_ptr() &&
1369 n->in(j)->bottom_type()->make_ptr()->make_oopptr()) {
1370 fatal("%s not covered", n->Name());
1371 }
1372 }
1373 }
1374 }
1375
1376 if (n->is_SafePoint()) {
1377 SafePointNode* sfpt = n->as_SafePoint();
1378 if (verify_no_useless_barrier && sfpt->jvms() != NULL) {
1379 for (uint i = sfpt->jvms()->scloff(); i < sfpt->jvms()->endoff(); i++) {
1380 if (!ShenandoahBarrierNode::verify_helper(sfpt->in(i), phis, visited, ShenandoahLoad, trace, barriers_used)) {
1381 phis.clear();
1382 visited.Reset();
1383 }
1384 }
1385 }
1386 }
1387 for( uint i = 0; i < n->len(); ++i ) {
1388 Node *m = n->in(i);
1389 if (m == NULL) continue;
1390
1391 // In most cases, inputs should be known to be non null. If it's
1392 // not the case, it could be a missing cast_not_null() in an
1393 // intrinsic or support might be needed in AddPNode::Ideal() to
1394 // avoid a NULL+offset input.
1395 if (!(n->is_Phi() ||
1396 (n->is_SafePoint() && (!n->is_CallRuntime() || !strcmp(n->as_Call()->_name, "shenandoah_wb_pre") || !strcmp(n->as_Call()->_name, "unsafe_arraycopy"))) ||
1397 n->Opcode() == Op_CmpP ||
1398 n->Opcode() == Op_CmpN ||
1399 (n->Opcode() == Op_StoreP && i == StoreNode::ValueIn) ||
1400 (n->Opcode() == Op_StoreN && i == StoreNode::ValueIn) ||
1401 n->is_ConstraintCast() ||
1402 n->Opcode() == Op_Return ||
1403 n->Opcode() == Op_Conv2B ||
1404 n->is_AddP() ||
1405 n->Opcode() == Op_CMoveP ||
1406 n->Opcode() == Op_CMoveN ||
1407 n->Opcode() == Op_Rethrow ||
1408 n->is_MemBar() ||
1409 n->is_Mem() ||
1410 n->Opcode() == Op_AryEq ||
1411 n->Opcode() == Op_SCMemProj ||
1412 n->Opcode() == Op_EncodeP ||
1413 n->Opcode() == Op_DecodeN)) {
1414 if (m->bottom_type()->make_oopptr() && m->bottom_type()->make_oopptr()->meet(TypePtr::NULL_PTR) == m->bottom_type()) {
1415 report_verify_failure("Shenandoah verification: null input", n, m);
1416 }
1417 }
1418
1419 wq.push(m);
1420 }
1421 }
1422
1423 if (verify_no_useless_barrier) {
1424 for (int i = 0; i < barriers.length(); i++) {
1425 Node* n = barriers.at(i);
1426 if (!barriers_used.member(n)) {
1427 tty->print("XXX useless barrier"); n->dump(-2);
1428 ShouldNotReachHere();
1429 }
1430 }
1431 }
1432 }
1433 #endif
1434
1435 MergeMemNode* ShenandoahWriteBarrierNode::allocate_merge_mem(Node* mem, int alias, Node* rep_proj, Node* rep_ctrl, PhaseIdealLoop* phase) {
1436 MergeMemNode* mm = MergeMemNode::make(mem);
1437 mm->set_memory_at(alias, rep_proj);
1438 phase->register_new_node(mm, rep_ctrl);
1439 return mm;
1440 }
1441
1442 MergeMemNode* ShenandoahWriteBarrierNode::clone_merge_mem(Node* u, Node* mem, int alias, Node* rep_proj, Node* rep_ctrl, DUIterator& i, PhaseIdealLoop* phase) {
1443 MergeMemNode* newmm = NULL;
1444 MergeMemNode* u_mm = u->as_MergeMem();
1445 Node* c = phase->get_ctrl(u);
1446 if (phase->is_dominator(c, rep_ctrl)) {
1447 c = rep_ctrl;
1448 } else {
1449 assert(phase->is_dominator(rep_ctrl, c), "one must dominate the other");
1450 }
1451 if (u->outcnt() == 1) {
1452 if (u->req() > (uint)alias && u->in(alias) == mem) {
1453 phase->igvn().replace_input_of(u, alias, rep_proj);
1454 --i;
1455 } else {
1456 phase->igvn().rehash_node_delayed(u);
1457 u_mm->set_memory_at(alias, rep_proj);
1458 }
1459 newmm = u_mm;
1460 phase->set_ctrl_and_loop(u, c);
1461 } else {
1462 // can't simply clone u and then change one of its input because
1463 // it adds and then removes an edge which messes with the
1464 // DUIterator
1465 newmm = MergeMemNode::make(u_mm->base_memory());
1466 for (uint j = 0; j < u->req(); j++) {
1467 if (j < newmm->req()) {
1468 if (j == (uint)alias) {
1469 newmm->set_req(j, rep_proj);
1470 } else if (newmm->in(j) != u->in(j)) {
1471 newmm->set_req(j, u->in(j));
1472 }
1473 } else if (j == (uint)alias) {
1474 newmm->add_req(rep_proj);
1475 } else {
1476 newmm->add_req(u->in(j));
1477 }
1478 }
1479 if ((uint)alias >= u->req()) {
1480 newmm->set_memory_at(alias, rep_proj);
1481 }
1482 phase->register_new_node(newmm, c);
1483 }
1484 return newmm;
1485 }
1486
1487 bool ShenandoahWriteBarrierNode::should_process_phi(Node* phi, int alias, Compile* C) {
1488 if (phi->adr_type() == TypePtr::BOTTOM) {
1489 Node* region = phi->in(0);
1490 for (DUIterator_Fast jmax, j = region->fast_outs(jmax); j < jmax; j++) {
1491 Node* uu = region->fast_out(j);
1492 if (uu->is_Phi() && uu != phi && uu->bottom_type() == Type::MEMORY && C->get_alias_index(uu->adr_type()) == alias) {
1493 return false;
1494 }
1495 }
1496 return true;
1497 }
1498 return C->get_alias_index(phi->adr_type()) == alias;
1499 }
1500
1501 bool ShenandoahBarrierNode::is_dominator_same_ctrl(Node*c, Node* d, Node* n, PhaseIdealLoop* phase) {
1502 // That both nodes have the same control is not sufficient to prove
1503 // domination, verify that there's no path from d to n
1504 ResourceMark rm;
1505 Unique_Node_List wq;
1506 wq.push(d);
1507 for (uint next = 0; next < wq.size(); next++) {
1508 Node *m = wq.at(next);
1509 if (m == n) {
1510 return false;
1511 }
1512 if (m->is_Phi() && m->in(0)->is_Loop()) {
1513 assert(phase->ctrl_or_self(m->in(LoopNode::EntryControl)) != c, "following loop entry should lead to new control");
1514 } else {
1515 for (uint i = 0; i < m->req(); i++) {
1516 if (m->in(i) != NULL && phase->ctrl_or_self(m->in(i)) == c) {
1517 wq.push(m->in(i));
1518 }
1519 }
1520 }
1521 }
1522 return true;
1523 }
1524
1525 bool ShenandoahBarrierNode::is_dominator(Node *d_c, Node *n_c, Node* d, Node* n, PhaseIdealLoop* phase) {
1526 if (d_c != n_c) {
1527 return phase->is_dominator(d_c, n_c);
1528 }
1529 return is_dominator_same_ctrl(d_c, d, n, phase);
1530 }
1531
1532 Node* next_mem(Node* mem, int alias) {
1533 Node* res = NULL;
1534 if (mem->is_Proj()) {
1535 res = mem->in(0);
1536 } else if (mem->is_SafePoint() || mem->is_MemBar()) {
1537 res = mem->in(TypeFunc::Memory);
1538 } else if (mem->is_Phi()) {
1539 res = mem->in(1);
1540 } else if (mem->is_ShenandoahBarrier()) {
1541 res = mem->in(ShenandoahBarrierNode::Memory);
1542 } else if (mem->is_MergeMem()) {
1543 res = mem->as_MergeMem()->memory_at(alias);
1544 } else if (mem->is_Store() || mem->is_LoadStore() || mem->is_ClearArray()) {
1545 assert(alias = Compile::AliasIdxRaw, "following raw memory can't lead to a barrier");
1546 res = mem->in(MemNode::Memory);
1547 } else {
1548 #ifdef ASSERT
1549 mem->dump();
1550 #endif
1551 ShouldNotReachHere();
1552 }
1553 return res;
1554 }
1555
1556 bool suitable_mem(Node* mem, Node* old_mem, Node* rep_proj) {
1557 for (DUIterator_Fast imax, i = mem->fast_outs(imax); i < imax; i++) {
1558 Node* u = mem->fast_out(i);
1559 if (u->is_MergeMem()) {
1560 if (u->has_out_with(Op_MergeMem)) {
1561 // too complicated for now
1562 return false;
1563 }
1564 if (old_mem == u && rep_proj->has_out_with(Op_MergeMem)) {
1565 return false;
1566 }
1567 }
1568 if (u->Opcode() == Op_Unlock && mem->is_Proj() && mem->in(0)->Opcode() == Op_MemBarReleaseLock) {
1569 // would require a merge mem between unlock and the
1570 // preceding membar. Would confuse logic that eliminates
1571 // lock/unlock nodes.
1572 return false;
1573 }
1574 }
1575 return true;
1576 }
1577
1578 void ShenandoahWriteBarrierNode::fix_memory_uses(Node* mem, Node* replacement, Node* rep_proj, Node* rep_ctrl, int alias, PhaseIdealLoop* phase) {
1579 uint last =phase-> C->unique();
1580 MergeMemNode* mm = NULL;
1581 assert(mem->bottom_type() == Type::MEMORY, "");
1582 for (DUIterator i = mem->outs(); mem->has_out(i); i++) {
1583 Node* u = mem->out(i);
1584 if (u != replacement && u->_idx < last) {
1585 if (u->is_ShenandoahBarrier() && alias != Compile::AliasIdxRaw) {
1586 if (phase->C->get_alias_index(u->adr_type()) == alias && is_dominator(rep_ctrl, phase->ctrl_or_self(u), replacement, u, phase)) {
1587 phase->igvn().replace_input_of(u, u->find_edge(mem), rep_proj);
1588 assert(u->find_edge(mem) == -1, "only one edge");
1589 --i;
1590 }
1591 } else if (u->is_Mem()) {
1592 if (phase->C->get_alias_index(u->adr_type()) == alias && is_dominator(rep_ctrl, phase->ctrl_or_self(u), replacement, u, phase)) {
1593 assert(alias == Compile::AliasIdxRaw , "only raw memory can lead to a memory operation");
1594 phase->igvn().replace_input_of(u, u->find_edge(mem), rep_proj);
1595 assert(u->find_edge(mem) == -1, "only one edge");
1596 --i;
1597 }
1598 } else if (u->is_MergeMem()) {
1599 MergeMemNode* u_mm = u->as_MergeMem();
1600 if (u_mm->memory_at(alias) == mem) {
1601 MergeMemNode* newmm = NULL;
1602 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
1603 Node* uu = u->fast_out(j);
1604 assert(!uu->is_MergeMem(), "chain of MergeMems?");
1605 if (uu->is_Phi()) {
1606 if (should_process_phi(uu, alias, phase->C)) {
1607 Node* region = uu->in(0);
1608 int nb = 0;
1609 for (uint k = 1; k < uu->req(); k++) {
1610 if (uu->in(k) == u && phase->is_dominator(rep_ctrl, region->in(k))) {
1611 if (newmm == NULL) {
1612 newmm = clone_merge_mem(u, mem, alias, rep_proj, rep_ctrl, i, phase);
1613 }
1614 if (newmm != u) {
1615 phase->igvn().replace_input_of(uu, k, newmm);
1616 nb++;
1617 --jmax;
1618 }
1619 }
1620 }
1621 if (nb > 0) {
1622 --j;
1623 }
1624 }
1625 } else {
1626 if (rep_ctrl != uu && is_dominator(rep_ctrl, phase->ctrl_or_self(uu), replacement, uu, phase)) {
1627 if (newmm == NULL) {
1628 newmm = clone_merge_mem(u, mem, alias, rep_proj, rep_ctrl, i, phase);
1629 }
1630 if (newmm != u) {
1631 phase->igvn().replace_input_of(uu, uu->find_edge(u), newmm);
1632 --j, --jmax;
1633 }
1634 }
1635 }
1636 }
1637 }
1638 } else if (u->is_Phi()) {
1639 assert(u->bottom_type() == Type::MEMORY, "what else?");
1640 Node* region = u->in(0);
1641 if (should_process_phi(u, alias, phase->C)) {
1642 bool replaced = false;
1643 for (uint j = 1; j < u->req(); j++) {
1644 if (u->in(j) == mem && phase->is_dominator(rep_ctrl, region->in(j))) {
1645 Node* nnew = rep_proj;
1646 if (u->adr_type() == TypePtr::BOTTOM) {
1647 if (mm == NULL) {
1648 mm = allocate_merge_mem(mem, alias, rep_proj, rep_ctrl, phase);
1649 }
1650 nnew = mm;
1651 }
1652 phase->igvn().replace_input_of(u, j, nnew);
1653 replaced = true;
1654 }
1655 }
1656 if (replaced) {
1657 --i;
1658 }
1659
1660 }
1661 } else if ((u->adr_type() == TypePtr::BOTTOM && u->Opcode() != Op_StrInflatedCopy) ||
1662 u->adr_type() == NULL) {
1663 assert(u->adr_type() != NULL ||
1664 u->Opcode() == Op_Rethrow ||
1665 u->Opcode() == Op_Return ||
1666 u->Opcode() == Op_SafePoint ||
1667 (u->is_CallStaticJava() && u->as_CallStaticJava()->uncommon_trap_request() != 0) ||
1668 (u->is_CallStaticJava() && u->as_CallStaticJava()->_entry_point == OptoRuntime::rethrow_stub()) ||
1669 u->Opcode() == Op_CallLeaf, "");
1670 if (is_dominator(rep_ctrl, phase->ctrl_or_self(u), replacement, u, phase)) {
1671 if (mm == NULL) {
1672 mm = allocate_merge_mem(mem, alias, rep_proj, rep_ctrl, phase);
1673 }
1674 phase->igvn().replace_input_of(u, u->find_edge(mem), mm);
1675 --i;
1676 }
1677 } else if (phase->C->get_alias_index(u->adr_type()) == alias) {
1678 if (is_dominator(rep_ctrl, phase->ctrl_or_self(u), replacement, u, phase)) {
1679 phase->igvn().replace_input_of(u, u->find_edge(mem), rep_proj);
1680 --i;
1681 }
1682 }
1683 }
1684 }
1685 }
1686
1687 Node* ShenandoahBarrierNode::no_branches(Node* c, Node* dom, bool allow_one_proj, PhaseIdealLoop* phase) {
1688 Node* iffproj = NULL;
1689 while (c != dom) {
1690 Node* next = phase->idom(c);
1691 assert(next->unique_ctrl_out() == c || c->is_Proj() || c->is_Region(), "multiple control flow out but no proj or region?");
1692 if (c->is_Region()) {
1693 ResourceMark rm;
1694 Unique_Node_List wq;
1695 wq.push(c);
1696 for (uint i = 0; i < wq.size(); i++) {
1697 Node *n = wq.at(i);
1698 if (n->is_Region()) {
1699 for (uint j = 1; j < n->req(); j++) {
1700 if (n->in(j) != next) {
1701 wq.push(n->in(j));
1702 }
1703 }
1704 } else {
1705 if (n->in(0) != next) {
1706 wq.push(n->in(0));
1707 }
1708 }
1709 }
1710 for (DUIterator_Fast imax, i = next->fast_outs(imax); i < imax; i++) {
1711 Node* u = next->fast_out(i);
1712 if (u->is_CFG()) {
1713 if (!wq.member(u)) {
1714 return NodeSentinel;
1715 }
1716 }
1717 }
1718
1719 } else if (c->is_Proj()) {
1720 if (c->is_IfProj()) {
1721 if (c->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none) != NULL) {
1722 // continue;
1723 } else {
1724 if (!allow_one_proj) {
1725 return NodeSentinel;
1726 }
1727 if (iffproj == NULL) {
1728 iffproj = c;
1729 } else {
1730 return NodeSentinel;
1731 }
1732 }
1733 } else if (c->Opcode() == Op_JumpProj) {
1734 return NodeSentinel; // unsupported
1735 } else if (c->Opcode() == Op_CatchProj) {
1736 return NodeSentinel; // unsupported
1737 } else if (c->Opcode() == Op_CProj && next->Opcode() == Op_NeverBranch) {
1738 return NodeSentinel; // unsupported
1739 } else {
1740 assert(next->unique_ctrl_out() == c, "unsupported branch pattern");
1741 }
1742 }
1743 c = next;
1744 }
1745 return iffproj;
1746 }
1747
1748 #ifdef ASSERT
1749 void ShenandoahWriteBarrierNode::memory_dominates_all_paths_helper(Node* c, Node* rep_ctrl, Unique_Node_List& controls, PhaseIdealLoop* phase) {
1750 const bool trace = false;
1751 if (trace) { tty->print("X control is"); c->dump(); }
1752
1753 uint start = controls.size();
1754 controls.push(c);
1755 for (uint i = start; i < controls.size(); i++) {
1756 Node *n = controls.at(i);
1757
1758 if (trace) { tty->print("X from"); n->dump(); }
1759
1760 if (n == rep_ctrl) {
1761 continue;
1762 }
1763
1764 if (n->is_Proj()) {
1765 Node* n_dom = n->in(0);
1766 IdealLoopTree* n_dom_loop = phase->get_loop(n_dom);
1767 if (n->is_IfProj() && n_dom->outcnt() == 2) {
1768 n_dom_loop = phase->get_loop(n_dom->as_If()->proj_out(n->as_Proj()->_con == 0 ? 1 : 0));
1769 }
1770 if (n_dom_loop != phase->ltree_root()) {
1771 Node* tail = n_dom_loop->tail();
1772 if (tail->is_Region()) {
1773 for (uint j = 1; j < tail->req(); j++) {
1774 if (phase->is_dominator(n_dom, tail->in(j)) && !phase->is_dominator(n, tail->in(j))) {
1775 assert(phase->is_dominator(rep_ctrl, tail->in(j)), "why are we here?");
1776 // entering loop from below, mark backedge
1777 if (trace) { tty->print("X pushing backedge"); tail->in(j)->dump(); }
1778 controls.push(tail->in(j));
1779 //assert(n->in(0) == n_dom, "strange flow control");
1780 }
1781 }
1782 } else if (phase->get_loop(n) != n_dom_loop && phase->is_dominator(n_dom, tail)) {
1783 // entering loop from below, mark backedge
1784 if (trace) { tty->print("X pushing backedge"); tail->dump(); }
1785 controls.push(tail);
1786 //assert(n->in(0) == n_dom, "strange flow control");
1787 }
1788 }
1789 }
1790
1791 if (n->is_Loop()) {
1792 Node* c = n->in(LoopNode::EntryControl);
1793 if (trace) { tty->print("X pushing"); c->dump(); }
1794 controls.push(c);
1795 } else if (n->is_Region()) {
1796 for (uint i = 1; i < n->req(); i++) {
1797 Node* c = n->in(i);
1798 if (trace) { tty->print("X pushing"); c->dump(); }
1799 controls.push(c);
1800 }
1801 } else {
1802 Node* c = n->in(0);
1803 if (trace) { tty->print("X pushing"); c->dump(); }
1804 controls.push(c);
1805 }
1806 }
1807 }
1808
1809 bool ShenandoahWriteBarrierNode::memory_dominates_all_paths(Node* mem, Node* rep_ctrl, int alias, PhaseIdealLoop* phase) {
1810 const bool trace = false;
1811 if (trace) {
1812 tty->print("XXX mem is"); mem->dump();
1813 tty->print("XXX rep ctrl is"); rep_ctrl->dump();
1814 tty->print_cr("XXX alias is %d", alias);
1815 }
1816 ResourceMark rm;
1817 Unique_Node_List wq;
1818 Unique_Node_List controls;
1819 wq.push(mem);
1820 for (uint next = 0; next < wq.size(); next++) {
1821 Node *nn = wq.at(next);
1822 if (trace) { tty->print("XX from mem"); nn->dump(); }
1823 assert(nn->bottom_type() == Type::MEMORY, "memory only");
1824
1825 if (nn->is_Phi()) {
1826 Node* r = nn->in(0);
1827 for (DUIterator_Fast jmax, j = r->fast_outs(jmax); j < jmax; j++) {
1828 Node* u = r->fast_out(j);
1829 if (u->is_Phi() && u->bottom_type() == Type::MEMORY && u != nn &&
1830 (u->adr_type() == TypePtr::BOTTOM || phase->C->get_alias_index(u->adr_type()) == alias)) {
1831 if (trace) { tty->print("XX Next mem (other phi)"); u->dump(); }
1832 wq.push(u);
1833 }
1834 }
1835 }
1836
1837 for (DUIterator_Fast imax, i = nn->fast_outs(imax); i < imax; i++) {
1838 Node* use = nn->fast_out(i);
1839
1840 if (trace) { tty->print("XX use %p", use->adr_type()); use->dump(); }
1841 if (use->is_CFG()) {
1842 assert(use->in(TypeFunc::Memory) == nn, "bad cfg node");
1843 Node* c = use->in(0);
1844 if (phase->is_dominator(rep_ctrl, c)) {
1845 memory_dominates_all_paths_helper(c, rep_ctrl, controls, phase);
1846 } else if (use->is_CallStaticJava() && use->as_CallStaticJava()->uncommon_trap_request() != 0 && c->is_Region()) {
1847 Node* region = c;
1848 if (trace) { tty->print("XX unc region"); region->dump(); }
1849 for (uint j = 1; j < region->req(); j++) {
1850 if (phase->is_dominator(rep_ctrl, region->in(j))) {
1851 if (trace) { tty->print("XX unc follows"); region->in(j)->dump(); }
1852 memory_dominates_all_paths_helper(region->in(j), rep_ctrl, controls, phase);
1853 }
1854 }
1855 }
1856 //continue;
1857 } else if (use->is_Phi()) {
1858 assert(use->bottom_type() == Type::MEMORY, "bad phi");
1859 if ((use->adr_type() == TypePtr::BOTTOM /*&& !shenandoah_has_alias_phi(C, use, alias)*/) ||
1860 phase->C->get_alias_index(use->adr_type()) == alias) {
1861 for (uint j = 1; j < use->req(); j++) {
1862 if (use->in(j) == nn) {
1863 Node* c = use->in(0)->in(j);
1864 if (phase->is_dominator(rep_ctrl, c)) {
1865 memory_dominates_all_paths_helper(c, rep_ctrl, controls, phase);
1866 }
1867 }
1868 }
1869 }
1870 // continue;
1871 }
1872
1873 if (use->is_MergeMem()) {
1874 if (use->as_MergeMem()->memory_at(alias) == nn) {
1875 if (trace) { tty->print("XX Next mem"); use->dump(); }
1876 // follow the memory edges
1877 wq.push(use);
1878 }
1879 } else if (use->is_Phi()) {
1880 assert(use->bottom_type() == Type::MEMORY, "bad phi");
1881 if ((use->adr_type() == TypePtr::BOTTOM /*&& !shenandoah_has_alias_phi(C, use, alias)*/) ||
1882 phase->C->get_alias_index(use->adr_type()) == alias) {
1883 if (trace) { tty->print("XX Next mem"); use->dump(); }
1884 // follow the memory edges
1885 wq.push(use);
1886 }
1887 } else if (use->bottom_type() == Type::MEMORY &&
1888 (use->adr_type() == TypePtr::BOTTOM || phase->C->get_alias_index(use->adr_type()) == alias)) {
1889 if (trace) { tty->print("XX Next mem"); use->dump(); }
1890 // follow the memory edges
1891 wq.push(use);
1892 } else if ((use->is_SafePoint() || use->is_MemBar()) &&
1893 (use->adr_type() == TypePtr::BOTTOM || phase->C->get_alias_index(use->adr_type()) == alias)) {
1894 for (DUIterator_Fast jmax, j = use->fast_outs(jmax); j < jmax; j++) {
1895 Node* u = use->fast_out(j);
1896 if (u->bottom_type() == Type::MEMORY) {
1897 if (trace) { tty->print("XX Next mem"); u->dump(); }
1898 // follow the memory edges
1899 wq.push(u);
1900 }
1901 }
1902 } else if (use->Opcode() == Op_ShenandoahWriteBarrier && phase->C->get_alias_index(use->adr_type()) == alias) {
1903 Node* m = use->find_out_with(Op_ShenandoahWBMemProj);
1904 if (m != NULL) {
1905 if (trace) { tty->print("XX Next mem"); m->dump(); }
1906 // follow the memory edges
1907 wq.push(m);
1908 }
1909 }
1910 }
1911 }
1912
1913 if (controls.size() == 0) {
1914 return false;
1915 }
1916
1917 for (uint i = 0; i < controls.size(); i++) {
1918 Node *n = controls.at(i);
1919
1920 if (trace) { tty->print("X checking"); n->dump(); }
1921
1922 if (n->unique_ctrl_out() != NULL) {
1923 continue;
1924 }
1925
1926 if (n->Opcode() == Op_NeverBranch) {
1927 Node* taken = n->as_Multi()->proj_out(0);
1928 if (!controls.member(taken)) {
1929 if (trace) { tty->print("X not seen"); taken->dump(); }
1930 return false;
1931 }
1932 continue;
1933 }
1934
1935 for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
1936 Node* u = n->fast_out(j);
1937
1938 if (u->is_CFG()) {
1939 if (!controls.member(u)) {
1940 if (u->is_Proj() && u->as_Proj()->is_uncommon_trap_proj(Deoptimization::Reason_none)) {
1941 if (trace) { tty->print("X not seen but unc"); u->dump(); }
1942 } else {
1943 Node* c = u;
1944 do {
1945 c = c->unique_ctrl_out();
1946 } while (c != NULL && c->is_Region());
1947 if (c != NULL && c->Opcode() == Op_Halt) {
1948 if (trace) { tty->print("X not seen but halt"); c->dump(); }
1949 } else {
1950 if (trace) { tty->print("X not seen"); u->dump(); }
1951 return false;
1952 }
1953 }
1954 } else {
1955 if (trace) { tty->print("X seen"); u->dump(); }
1956 }
1957 }
1958 }
1959 }
1960 return true;
1961 }
1962 #endif
1963
1964 static bool has_mem_phi(Compile* C, Node* region, int alias) {
1965 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
1966 Node* use = region->fast_out(i);
1967 if (use->is_Phi() && use->bottom_type() == Type::MEMORY &&
1968 (C->get_alias_index(use->adr_type()) == alias)) {
1969 return true;
1970 }
1971 }
1972 return false;
1973 }
1974
1975 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) {
1976 const bool trace = false;
1977 Node_List wq;
1978 wq.push(c);
1979
1980 #ifdef ASSERT
1981 if (trace) { tty->print("YYY from"); c->dump(); }
1982 if (trace) { tty->print("YYY with mem"); mem->dump(); }
1983 #endif
1984
1985 while(wq.size() > 0) {
1986 c = wq.pop();
1987
1988 while (!c->is_Region() || c->is_Loop()) {
1989 #ifdef ASSERT
1990 if (trace) { tty->print("YYY"); c->dump(); }
1991 #endif
1992 assert(c->is_CFG(), "node should be control node");
1993 if (c == mem_ctrl || phase->is_dominator(c, rep_ctrl)) {
1994 c = NULL;
1995 break;
1996 } else if (c->is_Loop()) {
1997 c = c->in(LoopNode::EntryControl);
1998 } else {
1999 c = c->in(0);
2000 }
2001 }
2002 if (c == NULL) {
2003 continue;
2004 }
2005
2006 #ifdef ASSERT
2007 if (trace) { tty->print("YYY new region"); c->dump(); }
2008 #endif
2009
2010 bool has_phi = has_mem_phi(phase->C, c, alias);
2011 if (!has_phi) {
2012
2013 Node* m_ctrl = NULL;
2014 Node* m = dom_mem(mem, c, alias, m_ctrl, phase);
2015 if (m == NULL) {
2016 return false;
2017 }
2018
2019 #ifdef ASSERT
2020 if (trace) { tty->print("YYY mem "); m->dump(); }
2021 #endif
2022
2023 if (controls.test(c->_idx)) {
2024 int i;
2025 for (i = 0; i < regions.length() && regions.at(i) != c; i+=2) {
2026 // deliberately empty, rolling over the regions
2027 }
2028 assert(i < regions.length(), "missing region");
2029 Node* prev_m = regions.at(i+1);
2030 if (prev_m == m) {
2031 continue;
2032 }
2033 #ifdef ASSERT
2034 if (trace) { tty->print("YYY prev mem "); prev_m->dump(); }
2035 #endif
2036 Node* prev_m_ctrl = phase->ctrl_or_self(prev_m);
2037 assert(is_dominator(m_ctrl, prev_m_ctrl, m, prev_m, phase) ||
2038 is_dominator(prev_m_ctrl, m_ctrl, prev_m, m, phase), "one should dominate the other");
2039 if (is_dominator(m_ctrl, prev_m_ctrl, m, prev_m, phase)) {
2040 continue;
2041 }
2042 #ifdef ASSERT
2043 if (trace) { tty->print("YYY Fixing "); c->dump(); }
2044 #endif
2045 regions.at_put(i+1, m);
2046 } else {
2047 #ifdef ASSERT
2048 if (trace) { tty->print("YYY Pushing "); c->dump(); }
2049 #endif
2050 regions.push(c);
2051 regions.push(m);
2052 }
2053 } else {
2054 continue;
2055 }
2056
2057 controls.set(c->_idx);
2058
2059 for (uint i = 1; i < c->req(); i++) {
2060 wq.push(c->in(i));
2061 }
2062 }
2063 return true;
2064 }
2065
2066
2067 bool ShenandoahWriteBarrierNode::fix_mem_phis(Node* mem, Node* mem_ctrl, Node* rep_ctrl, int alias, PhaseIdealLoop* phase) {
2068 GrowableArray<Node*> regions;
2069 VectorSet controls(Thread::current()->resource_area());
2070 const bool trace = false;
2071
2072 #ifdef ASSERT
2073 if (trace) { tty->print("YYY mem is "); mem->dump(); }
2074 if (trace) { tty->print("YYY mem ctrl is "); mem_ctrl->dump(); }
2075 if (trace) { tty->print("YYY rep ctrl is "); rep_ctrl->dump(); }
2076 if (trace) { tty->print_cr("YYY alias is %d", alias); }
2077 #endif
2078
2079 // Walk memory edges from mem until we hit a memory point where
2080 // control is known then follow the control up looking for regions
2081 // with no memory Phi for alias
2082 Unique_Node_List wq;
2083 wq.push(mem);
2084
2085 for (uint next = 0; next < wq.size(); next++) {
2086 Node *n = wq.at(next);
2087 #ifdef ASSERT
2088 if (trace) { tty->print("YYY from (2) "); n->dump(); }
2089 #endif
2090 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2091 Node* u = n->fast_out(i);
2092 #ifdef ASSERT
2093 if (trace) { tty->print("YYY processing "); u->dump(); }
2094 #endif
2095 if (u->is_Phi()) {
2096 assert(u->bottom_type() == Type::MEMORY, "strange memory graph");
2097 if (should_process_phi(u, alias, phase->C)) {
2098 for (uint j = 1; j < u->req(); j++) {
2099 if (u->in(j) == n) {
2100 Node *c = u->in(0)->in(j);
2101 if (!fix_mem_phis_helper(c, n, mem_ctrl, rep_ctrl, alias, controls, regions, phase)) {
2102 return false;
2103 }
2104 }
2105 }
2106 }
2107 #ifdef ASSERT
2108 } else if (u->is_CallStaticJava() && u->as_CallStaticJava()->uncommon_trap_request() != 0) {
2109 if (!fix_mem_phis_helper(u->in(0), n, mem_ctrl, rep_ctrl, alias, controls, regions, phase)) {
2110 return false;
2111 }
2112 #endif
2113 } else if ((u->is_CFG() && u->adr_type() == TypePtr::BOTTOM) || u->Opcode() == Op_Rethrow || u->Opcode() == Op_Return) {
2114 if (!fix_mem_phis_helper(u->in(0), n, mem_ctrl, rep_ctrl, alias, controls, regions, phase)) {
2115 return false;
2116 }
2117 } else if (u->is_MergeMem() && u->as_MergeMem()->memory_at(alias) == n) {
2118 wq.push(u);
2119 } else if (u->Opcode() == Op_ShenandoahWriteBarrier && phase->C->get_alias_index(u->adr_type()) == alias) {
2120 Node* m = u->find_out_with(Op_ShenandoahWBMemProj);
2121 if (m != NULL) {
2122 wq.push(m);
2123 }
2124 }
2125 }
2126 }
2127 #ifdef ASSERT
2128 if (trace) {
2129 tty->print_cr("XXXXXXXXXXXXXXXXXXXX");
2130 for (int i = 0; i < regions.length(); i++) {
2131 Node* r = regions.at(i);
2132 tty->print("%d", i); r->dump();
2133 }
2134 tty->print_cr("XXXXXXXXXXXXXXXXXXXX");
2135 }
2136 #endif
2137
2138 if (regions.length() == 0) {
2139 return true;
2140 }
2141
2142 {
2143 int i = 0;
2144 for (; i < regions.length(); i+=2) {
2145 Node* region = regions.at(i);
2146 bool has_phi = false;
2147 for (DUIterator_Fast jmax, j = region->fast_outs(jmax); j < jmax && !has_phi; j++) {
2148 Node* u = region->fast_out(j);
2149 if (u->is_Phi() && u->bottom_type() == Type::MEMORY &&
2150 (u->adr_type() == TypePtr::BOTTOM || phase->C->get_alias_index(u->adr_type()) == alias)) {
2151 has_phi = true;
2152 }
2153 }
2154 if (!has_phi) {
2155 break;
2156 }
2157 }
2158 if (i == regions.length()) {
2159 return true;
2160 }
2161 }
2162
2163 // Try to restrict the update to path that post dominates rep_ctrl
2164 int k = 0;
2165 int start = 0;
2166 int end = 0;
2167 do {
2168 start = end;
2169 end = k;
2170 for (int i = end; i < regions.length(); i+=2) {
2171 Node* r = regions.at(i);
2172 int prev = k;
2173 for (uint j = 1; j < r->req() && prev == k; j++) {
2174 if (end == 0) {
2175 if (phase->is_dominator(rep_ctrl, r->in(j))) {
2176 Node* mem = regions.at(i+1);
2177 regions.at_put(i, regions.at(k));
2178 regions.at_put(i+1, regions.at(k+1));
2179 regions.at_put(k, r);
2180 regions.at_put(k+1, mem);
2181 k+=2;
2182 }
2183 } else {
2184 for (int l = start; l < end && prev == k; l+=2) {
2185 Node* r2 = regions.at(l);
2186 if (phase->is_dominator(r2, r->in(j))) {
2187 Node* mem = regions.at(i+1);
2188 regions.at_put(i, regions.at(k));
2189 regions.at_put(i+1, regions.at(k+1));
2190 regions.at_put(k, r);
2191 regions.at_put(k+1, mem);
2192 k+=2;
2193 }
2194 }
2195 }
2196 }
2197 }
2198 #ifdef ASSERT
2199 if (trace) { tty->print_cr("k = %d start = %d end = %d", k, start, end); }
2200 #endif
2201 } while(k != end);
2202
2203 #ifdef ASSERT
2204 if (end != regions.length()) {
2205 if (trace) { tty->print_cr("Compacting %d -> %d", regions.length(), end); }
2206 }
2207 #endif
2208 regions.trunc_to(end);
2209
2210 #ifdef ASSERT
2211 if (trace) {
2212 tty->print_cr("XXXXXXXXXXXXXXXXXXXX");
2213 for (int i = 0; i < regions.length(); i++) {
2214 Node* r = regions.at(i);
2215 tty->print("%d", i); r->dump();
2216 }
2217 tty->print_cr("XXXXXXXXXXXXXXXXXXXX");
2218 }
2219 #endif
2220
2221 // Creating new phis must be done in post order
2222 while (regions.length() > 0) {
2223 int i = 0;
2224 for (; i < regions.length(); i+=2) {
2225 Node* r1 = regions.at(i);
2226 bool is_dom = false;
2227 for (int j = 0; j < regions.length() && !is_dom; j+=2) {
2228 if (i != j) {
2229 Node* r2 = regions.at(j);
2230 for (uint k = 1; k < r2->req() && !is_dom; k++) {
2231 if (phase->is_dominator(r1, r2->in(k))) {
2232 is_dom = true;
2233 }
2234 }
2235 }
2236 }
2237 if (!is_dom) {
2238 break;
2239 }
2240 }
2241 assert(i < regions.length(), "need one");
2242 Node* r = regions.at(i);
2243 Node* m = regions.at(i+1);
2244 regions.delete_at(i+1);
2245 regions.delete_at(i);
2246
2247 if (!suitable_mem(m, NULL, NULL)) {
2248 return false;
2249 }
2250 Node* phi = PhiNode::make(r, m, Type::MEMORY, phase->C->get_adr_type(alias));
2251 #ifdef ASSERT
2252 if (trace) { tty->print("YYY Adding new mem phi "); phi->dump(); }
2253 #endif
2254 phase->register_new_node(phi, r);
2255
2256 fix_memory_uses(m, phi, phi, r, phase->C->get_alias_index(phi->adr_type()), phase);
2257 assert(phi->outcnt() != 0, "new proj should have uses");
2258 if (phi->outcnt() == 0) {
2259 phase->igvn().remove_dead_node(phi);
2260 }
2261 }
2262
2263 return true;
2264 }
2265
2266 Node* ShenandoahBarrierNode::dom_mem(Node* mem, Node*& mem_ctrl, Node* n, Node* rep_ctrl, int alias, PhaseIdealLoop* phase) {
2267 ResourceMark rm;
2268 VectorSet wq(Thread::current()->resource_area());
2269 wq.set(mem->_idx);
2270 mem_ctrl = phase->get_ctrl(mem);
2271 while (!is_dominator(mem_ctrl, rep_ctrl, mem, n, phase)) {
2272 mem = next_mem(mem, alias);
2273 if (wq.test_set(mem->_idx)) {
2274 return NULL; // hit an unexpected loop
2275 }
2276 mem_ctrl = phase->ctrl_or_self(mem);
2277 }
2278 if (mem->is_MergeMem()) {
2279 mem = mem->as_MergeMem()->memory_at(alias);
2280 mem_ctrl = phase->ctrl_or_self(mem);
2281 }
2282 return mem;
2283 }
2284
2285 Node* ShenandoahBarrierNode::dom_mem(Node* mem, Node* ctrl, int alias, Node*& mem_ctrl, PhaseIdealLoop* phase) {
2286 ResourceMark rm;
2287 VectorSet wq(Thread::current()->resource_area());
2288 wq.set(mem->_idx);
2289 mem_ctrl = phase->ctrl_or_self(mem);
2290 while (!phase->is_dominator(mem_ctrl, ctrl) || mem_ctrl == ctrl) {
2291 mem = next_mem(mem, alias);
2292 if (wq.test_set(mem->_idx)) {
2293 return NULL;
2294 }
2295 mem_ctrl = phase->ctrl_or_self(mem);
2296 }
2297 if (mem->is_MergeMem()) {
2298 mem = mem->as_MergeMem()->memory_at(alias);
2299 mem_ctrl = phase->ctrl_or_self(mem);
2300 }
2301 return mem;
2302 }
2303
2304 Node* ShenandoahBarrierNode::try_common(Node *n_ctrl, PhaseIdealLoop* phase) {
2305 if (!phase->C->has_irreducible_loop()) {
2306 // We look for a write barrier whose memory edge dominates n
2307 // Either the replacement write barrier dominates n or we have,
2308 // for instance:
2309 // if ( ) {
2310 // read barrier n
2311 // } else {
2312 // write barrier
2313 // }
2314 // in which case replacing n by the write barrier causes the write
2315 // barrier to move above the if() and the memory Phi that merges
2316 // the memory state for both branches must be updated so both
2317 // inputs become the write barrier's memory projection (and the
2318 // Phi is optimized out) otherwise we risk loosing a memory
2319 // dependency.
2320 // Once we find a replacement write barrier, the code below fixes
2321 // the memory graph in cases like the one above.
2322 Node* val = in(ValueIn);
2323 Node* val_ctrl = phase->get_ctrl(val);
2324 Node* n_proj = find_out_with(Op_ShenandoahWBMemProj);
2325 Node* replacement = NULL;
2326 int alias = phase->C->get_alias_index(adr_type());
2327 Node* rep_ctrl = NULL;
2328 for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax && replacement == NULL; i++) {
2329 Node* u = val->fast_out(i);
2330 if (u != this && u->Opcode() == Op_ShenandoahWriteBarrier) {
2331 Node* u_mem = u->in(Memory);
2332 Node* u_proj = u->find_out_with(Op_ShenandoahWBMemProj);
2333 Node* u_ctrl = phase->get_ctrl(u);
2334 Node* u_mem_ctrl = phase->get_ctrl(u_mem);
2335 IdealLoopTree* n_loop = phase->get_loop(n_ctrl);
2336 IdealLoopTree* u_loop = phase->get_loop(u_ctrl);
2337
2338 Node* ctrl = phase->dom_lca(u_ctrl, n_ctrl);
2339
2340 if (ctrl->is_Proj() &&
2341 ctrl->in(0)->is_Call() &&
2342 ctrl->unique_ctrl_out() != NULL &&
2343 ctrl->unique_ctrl_out()->Opcode() == Op_Catch &&
2344 !phase->is_dominator(val_ctrl, ctrl->in(0)->in(0))) {
2345 continue;
2346 }
2347
2348 if (Opcode() == Op_ShenandoahWriteBarrier && u_proj == NULL && n_proj != NULL) {
2349 continue;
2350 }
2351
2352 IdealLoopTree* loop = phase->get_loop(ctrl);
2353
2354 // We don't want to move a write barrier in a loop
2355 // If the LCA is in a inner loop, try a control out of loop if possible
2356 bool loop_ok = true;
2357 while (!loop->is_member(u_loop) && (Opcode() != Op_ShenandoahWriteBarrier || !loop->is_member(n_loop))) {
2358 ctrl = phase->idom(ctrl);
2359 if (ctrl != val_ctrl && phase->is_dominator(ctrl, val_ctrl)) {
2360 loop_ok = false;
2361 break;
2362 }
2363 loop = phase->get_loop(ctrl);
2364 }
2365
2366 if (loop_ok) {
2367 if (ShenandoahDontIncreaseWBFreq) {
2368 Node* u_iffproj = no_branches(u_ctrl, ctrl, true, phase);
2369 if (Opcode() == Op_ShenandoahWriteBarrier) {
2370 Node* n_iffproj = no_branches(n_ctrl, ctrl, true, phase);
2371 if (u_iffproj == NULL || n_iffproj == NULL) {
2372 replacement = u;
2373 rep_ctrl = ctrl;
2374 } else if (u_iffproj != NodeSentinel && n_iffproj != NodeSentinel && u_iffproj->in(0) == n_iffproj->in(0)) {
2375 replacement = u;
2376 rep_ctrl = ctrl;
2377 }
2378 } else if (u_iffproj == NULL) {
2379 replacement = u;
2380 rep_ctrl = ctrl;
2381 }
2382 } else {
2383 replacement = u;
2384 rep_ctrl = ctrl;
2385 }
2386 }
2387 }
2388 }
2389 if (replacement != NULL) {
2390 if (rep_ctrl->is_Proj() &&
2391 rep_ctrl->in(0)->is_Call() &&
2392 rep_ctrl->unique_ctrl_out() != NULL &&
2393 rep_ctrl->unique_ctrl_out()->Opcode() == Op_Catch) {
2394 rep_ctrl = rep_ctrl->in(0)->in(0);
2395 assert(phase->is_dominator(val_ctrl, rep_ctrl), "bad control");
2396 } else {
2397 LoopNode* c = ShenandoahWriteBarrierNode::try_move_before_pre_loop(rep_ctrl, val_ctrl, phase);
2398 if (c != NULL) {
2399 rep_ctrl = ShenandoahWriteBarrierNode::move_above_predicates(c, val_ctrl, phase);
2400 } else {
2401 while (rep_ctrl->is_IfProj()) {
2402 CallStaticJavaNode* unc = rep_ctrl->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none);
2403 if (unc != NULL) {
2404 int req = unc->uncommon_trap_request();
2405 Deoptimization::DeoptReason trap_reason = Deoptimization::trap_request_reason(req);
2406 if ((trap_reason == Deoptimization::Reason_loop_limit_check ||
2407 trap_reason == Deoptimization::Reason_predicate ||
2408 trap_reason == Deoptimization::Reason_profile_predicate) &&
2409 phase->is_dominator(val_ctrl, rep_ctrl->in(0)->in(0))) {
2410 rep_ctrl = rep_ctrl->in(0)->in(0);
2411 continue;
2412 }
2413 }
2414 break;
2415 }
2416 }
2417 }
2418
2419 Node* mem = replacement->in(Memory);
2420 Node* old_mem = mem;
2421 Node* rep_proj = replacement->find_out_with(Op_ShenandoahWBMemProj);
2422 {
2423 Node* mem_ctrl = NULL;
2424
2425 mem = dom_mem(mem, mem_ctrl, this, rep_ctrl, alias, phase);
2426 if (mem == NULL) {
2427 return NULL;
2428 }
2429
2430 // Add a memory Phi for the slice of the write barrier to any
2431 // region that post dominates rep_ctrl and doesn't have one
2432 // already.
2433 if (rep_proj != NULL && !ShenandoahWriteBarrierNode::fix_mem_phis(mem, mem_ctrl, rep_ctrl, alias, phase)) {
2434 return NULL;
2435 }
2436
2437 assert(!ShenandoahVerifyOptoBarriers || ShenandoahWriteBarrierNode::memory_dominates_all_paths(mem, rep_ctrl, alias, phase), "can't fix the memory graph");
2438 }
2439 assert(phase->igvn().type(mem) == Type::MEMORY, "not memory");
2440
2441 if (rep_proj != NULL) {
2442 Node* old_mem = replacement->in(Memory);
2443 if (!suitable_mem(mem, old_mem, rep_proj)) {
2444 return NULL;
2445 }
2446
2447 if (replacement->in(Memory) != mem) {
2448 // tty->print("XXX setting memory of"); replacement->dump();
2449 // tty->print("XXX to"); mem->dump();
2450 for (DUIterator_Last imin, i = rep_proj->last_outs(imin); i >= imin; ) {
2451 Node* u = rep_proj->last_out(i);
2452 phase->igvn().rehash_node_delayed(u);
2453 int uses_found = u->replace_edge(rep_proj, old_mem);
2454 i -= uses_found;
2455 }
2456 phase->igvn().replace_input_of(replacement, Memory, mem);
2457 }
2458 phase->set_ctrl_and_loop(replacement, rep_ctrl);
2459 phase->igvn().replace_input_of(replacement, Control, rep_ctrl);
2460
2461 ShenandoahWriteBarrierNode::fix_memory_uses(mem, replacement, rep_proj, rep_ctrl, phase->C->get_alias_index(replacement->adr_type()), phase);
2462 assert(rep_proj->outcnt() != 0, "new proj should have uses");
2463 } else {
2464 if (replacement->in(Memory) != mem) {
2465 phase->igvn()._worklist.push(replacement->in(Memory));
2466 phase->igvn().replace_input_of(replacement, Memory, mem);
2467 }
2468 phase->set_ctrl_and_loop(replacement, rep_ctrl);
2469 phase->igvn().replace_input_of(replacement, Control, rep_ctrl);
2470 }
2471 if (Opcode() == Op_ShenandoahWriteBarrier) {
2472 if (n_proj != NULL) {
2473 phase->lazy_replace(n_proj, in(Memory));
2474 }
2475 }
2476 phase->lazy_replace(this, replacement);
2477 if (rep_proj != NULL) {
2478 phase->set_ctrl_and_loop(rep_proj, rep_ctrl);
2479 }
2480 return replacement;
2481 }
2482 }
2483
2484 return NULL;
2485 }
2486
2487 const TypePtr* ShenandoahBarrierNode::fix_addp_type(const TypePtr* res, Node* base) {
2488 if (UseShenandoahGC && ShenandoahBarriersForConst) {
2489 // With barriers on constant oops, if a field being accessed is a
2490 // static field, correct alias analysis requires that we look
2491 // beyond the barriers (that hide the constant) to find the actual
2492 // java class mirror constant.
2493 const TypeInstPtr* ti = res->isa_instptr();
2494 if (ti != NULL &&
2495 ti->const_oop() == NULL &&
2496 ti->klass() == ciEnv::current()->Class_klass() &&
2497 ti->offset() >= (ti->klass()->as_instance_klass()->size_helper() * wordSize)) {
2498 ResourceMark rm;
2499 Unique_Node_List wq;
2500 ciObject* const_oop = NULL;
2501 wq.push(base);
2502 for (uint i = 0; i < wq.size(); i++) {
2503 Node *n = wq.at(i);
2504 if (n->is_ShenandoahBarrier() ||
2505 (n->is_Mach() && n->as_Mach()->ideal_Opcode() == Op_ShenandoahReadBarrier)) {
2506 Node* m = n->in(ShenandoahBarrierNode::ValueIn);
2507 if (m != NULL) {
2508 wq.push(m);
2509 }
2510 } else if (n->is_Phi()) {
2511 for (uint j = 1; j < n->req(); j++) {
2512 Node* m = n->in(j);
2513 if (m != NULL) {
2514 wq.push(m);
2515 }
2516 }
2517 } else if (n->is_ConstraintCast() || (n->is_Mach() && n->as_Mach()->ideal_Opcode() == Op_CheckCastPP)) {
2518 Node* m = n->in(1);
2519 if (m != NULL) {
2520 wq.push(m);
2521 }
2522 } else {
2523 const TypeInstPtr* tn = n->bottom_type()->isa_instptr();
2524 if (tn != NULL) {
2525 if (tn->const_oop() != NULL) {
2526 if (const_oop == NULL) {
2527 const_oop = tn->const_oop();
2528 } else if (const_oop != tn->const_oop()) {
2529 const_oop = NULL;
2530 break;
2531 }
2532 } else {
2533 if (n->is_Proj()) {
2534 if (n->in(0)->Opcode() == Op_CallLeafNoFP) {
2535 if (n->in(0)->as_Call()->entry_point() != StubRoutines::shenandoah_wb_C()) {
2536 const_oop = NULL;
2537 break;
2538 }
2539 } else if (n->in(0)->is_MachCallLeaf()) {
2540 if (n->in(0)->as_MachCall()->entry_point() != StubRoutines::shenandoah_wb_C()) {
2541 const_oop = NULL;
2542 break;
2543 }
2544 }
2545 } else {
2546 fatal("2 different static fields being accessed with a single AddP");
2547 const_oop = NULL;
2548 break;
2549 }
2550 }
2551 } else {
2552 assert(n->bottom_type() == Type::TOP, "not an instance ptr?");
2553 }
2554 }
2555 }
2556 if (const_oop != NULL) {
2557 res = ti->cast_to_const(const_oop);
2558 }
2559 }
2560 }
2561 return res;
2562 }
2563
2564 static void disconnect_barrier_mem(Node* wb, PhaseIterGVN& igvn) {
2565 Node* mem_in = wb->in(ShenandoahBarrierNode::Memory);
2566 Node* proj = wb->find_out_with(Op_ShenandoahWBMemProj);
2567
2568 for (DUIterator_Last imin, i = proj->last_outs(imin); i >= imin; ) {
2569 Node* u = proj->last_out(i);
2570 igvn.rehash_node_delayed(u);
2571 int nb = u->replace_edge(proj, mem_in);
2572 assert(nb > 0, "no replacement?");
2573 i -= nb;
2574 }
2575 }
2576
2577 Node* ShenandoahWriteBarrierNode::move_above_predicates(LoopNode* cl, Node* val_ctrl, PhaseIdealLoop* phase) {
2578 Node* entry = cl->skip_strip_mined()->in(LoopNode::EntryControl);
2579 Node* above_pred = phase->skip_all_loop_predicates(entry);
2580 Node* ctrl = entry;
2581 while (ctrl != above_pred) {
2582 Node* next = ctrl->in(0);
2583 if (!phase->is_dominator(val_ctrl, next)) {
2584 break;
2585 }
2586 ctrl = next;
2587 }
2588 return ctrl;
2589 }
2590
2591 Node* ShenandoahWriteBarrierNode::try_move_before_loop_helper(LoopNode* cl, Node* val_ctrl, Node* mem, PhaseIdealLoop* phase) {
2592 assert(cl->is_Loop(), "bad control");
2593 Node* ctrl = move_above_predicates(cl, val_ctrl, phase);
2594 Node* mem_ctrl = NULL;
2595 int alias = phase->C->get_alias_index(adr_type());
2596 mem = dom_mem(mem, mem_ctrl, this, ctrl, alias, phase);
2597 if (mem == NULL) {
2598 return NULL;
2599 }
2600
2601 Node* old_mem = in(Memory);
2602 Node* proj = find_out_with(Op_ShenandoahWBMemProj);
2603 if (old_mem != mem && !suitable_mem(mem, old_mem, proj)) {
2604 return NULL;
2605 }
2606
2607 assert(!ShenandoahVerifyOptoBarriers || memory_dominates_all_paths(mem, ctrl, alias, phase), "can't fix the memory graph");
2608 phase->set_ctrl_and_loop(this, ctrl);
2609 phase->igvn().replace_input_of(this, Control, ctrl);
2610 if (old_mem != mem) {
2611 if (proj != NULL) {
2612 disconnect_barrier_mem(this, phase->igvn());
2613 fix_memory_uses(mem, this, proj, ctrl, phase->C->get_alias_index(adr_type()), phase);
2614 assert(proj->outcnt() > 0, "disconnected write barrier");
2615 }
2616 phase->igvn().replace_input_of(this, Memory, mem);
2617 }
2618 if (proj != NULL) {
2619 phase->set_ctrl_and_loop(proj, ctrl);
2620 }
2621 return this;
2622 }
2623
2624 LoopNode* ShenandoahWriteBarrierNode::try_move_before_pre_loop(Node* c, Node* val_ctrl, PhaseIdealLoop* phase) {
2625 // A write barrier between a pre and main loop can get in the way of
2626 // vectorization. Move it above the pre loop if possible
2627 CountedLoopNode* cl = NULL;
2628 if (c->is_IfFalse() &&
2629 c->in(0)->is_CountedLoopEnd()) {
2630 cl = c->in(0)->as_CountedLoopEnd()->loopnode();
2631 } else if (c->is_IfProj() &&
2632 c->in(0)->is_If() &&
2633 c->in(0)->in(0)->is_IfFalse() &&
2634 c->in(0)->in(0)->in(0)->is_CountedLoopEnd()) {
2635 cl = c->in(0)->in(0)->in(0)->as_CountedLoopEnd()->loopnode();
2636 }
2637 if (cl != NULL &&
2638 cl->is_pre_loop() &&
2639 val_ctrl != cl &&
2640 phase->is_dominator(val_ctrl, cl)) {
2641 return cl;
2642 }
2643 return NULL;
2644 }
2645
2646 Node* ShenandoahWriteBarrierNode::try_move_before_loop(Node *n_ctrl, PhaseIdealLoop* phase) {
2647 IdealLoopTree *n_loop = phase->get_loop(n_ctrl);
2648 Node* val = in(ValueIn);
2649 Node* val_ctrl = phase->get_ctrl(val);
2650 if (n_loop != phase->ltree_root() && !n_loop->_irreducible) {
2651 IdealLoopTree *val_loop = phase->get_loop(val_ctrl);
2652 Node* mem = in(Memory);
2653 IdealLoopTree *mem_loop = phase->get_loop(phase->get_ctrl(mem));
2654 if (!n_loop->is_member(val_loop) &&
2655 n_loop->is_member(mem_loop)) {
2656 Node* n_loop_head = n_loop->_head;
2657
2658 if (n_loop_head->is_Loop()) {
2659 LoopNode* loop = n_loop_head->as_Loop();
2660 if (n_loop_head->is_CountedLoop() && n_loop_head->as_CountedLoop()->is_main_loop()) {
2661 LoopNode* res = try_move_before_pre_loop(n_loop_head->in(LoopNode::EntryControl), val_ctrl, phase);
2662 if (res != NULL) {
2663 loop = res;
2664 }
2665 }
2666
2667 return try_move_before_loop_helper(loop, val_ctrl, mem, phase);
2668 }
2669 }
2670 }
2671 LoopNode* ctrl = try_move_before_pre_loop(in(0), val_ctrl, phase);
2672 if (ctrl != NULL) {
2673 return try_move_before_loop_helper(ctrl, val_ctrl, in(Memory), phase);
2674 }
2675 return NULL;
2676 }
2677
2678 void ShenandoahReadBarrierNode::try_move(Node *n_ctrl, PhaseIdealLoop* phase) {
2679 Node* mem = in(MemNode::Memory);
2680 int alias = phase->C->get_alias_index(adr_type());
2681 const bool trace = false;
2682
2683 #ifdef ASSERT
2684 if (trace) { tty->print("Trying to move mem of"); dump(); }
2685 #endif
2686
2687 Node* new_mem = mem;
2688
2689 ResourceMark rm;
2690 VectorSet seen(Thread::current()->resource_area());
2691 Node_List phis;
2692
2693 for (;;) {
2694 #ifdef ASSERT
2695 if (trace) { tty->print("Looking for dominator from"); mem->dump(); }
2696 #endif
2697 if (mem->is_Proj() && mem->in(0)->is_Start()) {
2698 if (new_mem != in(MemNode::Memory)) {
2699 #ifdef ASSERT
2700 if (trace) { tty->print("XXX Setting mem to"); new_mem->dump(); tty->print(" for "); dump(); }
2701 #endif
2702 phase->igvn().replace_input_of(this, MemNode::Memory, new_mem);
2703 }
2704 return;
2705 }
2706
2707 Node* candidate = mem;
2708 do {
2709 if (!is_independent(mem)) {
2710 if (trace) { tty->print_cr("Not independent"); }
2711 if (new_mem != in(MemNode::Memory)) {
2712 #ifdef ASSERT
2713 if (trace) { tty->print("XXX Setting mem to"); new_mem->dump(); tty->print(" for "); dump(); }
2714 #endif
2715 phase->igvn().replace_input_of(this, MemNode::Memory, new_mem);
2716 }
2717 return;
2718 }
2719 if (seen.test_set(mem->_idx)) {
2720 if (trace) { tty->print_cr("Already seen"); }
2721 ShouldNotReachHere();
2722 // Strange graph
2723 if (new_mem != in(MemNode::Memory)) {
2724 #ifdef ASSERT
2725 if (trace) { tty->print("XXX Setting mem to"); new_mem->dump(); tty->print(" for "); dump(); }
2726 #endif
2727 phase->igvn().replace_input_of(this, MemNode::Memory, new_mem);
2728 }
2729 return;
2730 }
2731 if (mem->is_Phi()) {
2732 phis.push(mem);
2733 }
2734 mem = next_mem(mem, alias);
2735 if (mem->bottom_type() == Type::MEMORY) {
2736 candidate = mem;
2737 }
2738 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");
2739 #ifdef ASSERT
2740 if (trace) { tty->print("Next mem is"); mem->dump(); }
2741 #endif
2742 } while (mem->bottom_type() != Type::MEMORY || !phase->is_dominator(phase->ctrl_or_self(mem), n_ctrl));
2743
2744 assert(mem->bottom_type() == Type::MEMORY, "bad mem");
2745
2746 bool not_dom = false;
2747 for (uint i = 0; i < phis.size() && !not_dom; i++) {
2748 Node* nn = phis.at(i);
2749
2750 #ifdef ASSERT
2751 if (trace) { tty->print("Looking from phi"); nn->dump(); }
2752 #endif
2753 assert(nn->is_Phi(), "phis only");
2754 for (uint j = 2; j < nn->req() && !not_dom; j++) {
2755 Node* m = nn->in(j);
2756 #ifdef ASSERT
2757 if (trace) { tty->print("Input %d is", j); m->dump(); }
2758 #endif
2759 while (m != mem && !seen.test_set(m->_idx)) {
2760 if (is_dominator(phase->ctrl_or_self(m), phase->ctrl_or_self(mem), m, mem, phase)) {
2761 not_dom = true;
2762 // Scheduling anomaly
2763 #ifdef ASSERT
2764 if (trace) { tty->print("Giving up"); m->dump(); }
2765 #endif
2766 break;
2767 }
2768 if (!is_independent(m)) {
2769 if (trace) { tty->print_cr("Not independent"); }
2770 if (new_mem != in(MemNode::Memory)) {
2771 #ifdef ASSERT
2772 if (trace) { tty->print("XXX Setting mem to"); new_mem->dump(); tty->print(" for "); dump(); }
2773 #endif
2774 phase->igvn().replace_input_of(this, MemNode::Memory, new_mem);
2775 }
2776 return;
2777 }
2778 if (m->is_Phi()) {
2779 phis.push(m);
2780 }
2781 m = next_mem(m, alias);
2782 #ifdef ASSERT
2783 if (trace) { tty->print("Next mem is"); m->dump(); }
2784 #endif
2785 }
2786 }
2787 }
2788 if (!not_dom) {
2789 new_mem = mem;
2790 phis.clear();
2791 } else {
2792 seen.Clear();
2793 }
2794 }
2795 }
2796
2797 CallStaticJavaNode* ShenandoahWriteBarrierNode::pin_and_expand_null_check(PhaseIterGVN& igvn) {
2798 Node* val = in(ValueIn);
2799
2800 #ifdef ASSERT
2801 const Type* val_t = igvn.type(val);
2802 assert(val_t->meet(TypePtr::NULL_PTR) != val_t, "should be not null");
2803 #endif
2804
2805 if (val->Opcode() == Op_CastPP &&
2806 val->in(0) != NULL &&
2807 val->in(0)->Opcode() == Op_IfTrue &&
2808 val->in(0)->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none) &&
2809 val->in(0)->in(0)->is_If() &&
2810 val->in(0)->in(0)->in(1)->Opcode() == Op_Bool &&
2811 val->in(0)->in(0)->in(1)->as_Bool()->_test._test == BoolTest::ne &&
2812 val->in(0)->in(0)->in(1)->in(1)->Opcode() == Op_CmpP &&
2813 val->in(0)->in(0)->in(1)->in(1)->in(1) == val->in(1) &&
2814 val->in(0)->in(0)->in(1)->in(1)->in(2)->bottom_type() == TypePtr::NULL_PTR) {
2815 assert(val->in(0)->in(0)->in(1)->in(1)->in(1) == val->in(1), "");
2816 CallStaticJavaNode* unc = val->in(0)->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none);
2817 return unc;
2818 }
2819 return NULL;
2820 }
2821
2822 void ShenandoahWriteBarrierNode::pin_and_expand_move_barrier(PhaseIdealLoop* phase, Unique_Node_List& uses) {
2823 Node* unc = pin_and_expand_null_check(phase->igvn());
2824 Node* val = in(ValueIn);
2825
2826 if (unc != NULL) {
2827 Node* ctrl = phase->get_ctrl(this);
2828 Node* unc_ctrl = val->in(0);
2829
2830 // Don't move write barrier in a loop
2831 IdealLoopTree* loop = phase->get_loop(ctrl);
2832 IdealLoopTree* unc_loop = phase->get_loop(unc_ctrl);
2833
2834 if (!unc_loop->is_member(loop)) {
2835 return;
2836 }
2837
2838 Node* branch = no_branches(ctrl, unc_ctrl, false, phase);
2839 assert(branch == NULL || branch == NodeSentinel, "was not looking for a branch");
2840 if (branch == NodeSentinel) {
2841 return;
2842 }
2843
2844
2845 RegionNode* r = new RegionNode(3);
2846 IfNode* iff = unc_ctrl->in(0)->as_If();
2847
2848 Node* ctrl_use = unc_ctrl->unique_ctrl_out();
2849 Node* c = unc_ctrl;
2850 Node* new_cast = clone_null_check(c, val, unc_ctrl, r, 1, phase);
2851
2852 phase->igvn().rehash_node_delayed(ctrl_use);
2853 int nb = ctrl_use->replace_edge(unc_ctrl, c);
2854 assert(nb == 1, "no update?");
2855 if (phase->idom(ctrl_use) == unc_ctrl) {
2856 phase->set_idom(ctrl_use, c, phase->dom_depth(ctrl_use));
2857 }
2858
2859 IfNode* new_iff = new_cast->in(0)->in(0)->as_If();
2860 fix_null_check(iff, unc, unc_ctrl, r, uses, phase);
2861 Node* iff_proj = iff->proj_out(0);
2862 r->init_req(2, iff_proj);
2863
2864 Node* new_bol = new_iff->in(1)->clone();
2865 Node* new_cmp = new_bol->in(1)->clone();
2866 assert(new_cmp->Opcode() == Op_CmpP, "broken");
2867 assert(new_cmp->in(1) == val->in(1), "broken");
2868 new_bol->set_req(1, new_cmp);
2869 new_cmp->set_req(1, this);
2870 phase->register_new_node(new_bol, new_iff->in(0));
2871 phase->register_new_node(new_cmp, new_iff->in(0));
2872 phase->igvn().replace_input_of(new_iff, 1, new_bol);
2873 phase->igvn().replace_input_of(new_cast, 1, this);
2874
2875 for (DUIterator_Fast imax, i = this->fast_outs(imax); i < imax; i++) {
2876 Node* u = this->fast_out(i);
2877 if (u == new_cast || u->Opcode() == Op_ShenandoahWBMemProj || u == new_cmp) {
2878 continue;
2879 }
2880 phase->igvn().rehash_node_delayed(u);
2881 int nb = u->replace_edge(this, new_cast);
2882 assert(nb > 0, "no update?");
2883 --i; imax -= nb;
2884 }
2885
2886 for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) {
2887 Node* u = val->fast_out(i);
2888 if (u == this) {
2889 continue;
2890 }
2891 phase->igvn().rehash_node_delayed(u);
2892 int nb = u->replace_edge(val, new_cast);
2893 assert(nb > 0, "no update?");
2894 --i; imax -= nb;
2895 }
2896
2897 uses.clear();
2898 uses.push(new_cast);
2899 for (uint next = 0; next < uses.size(); next++) {
2900 Node *n = uses.at(next);
2901 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2902 Node* u = n->fast_out(i);
2903 if (phase->has_ctrl(u) && phase->get_ctrl(u) == unc_ctrl) {
2904 phase->set_ctrl(u, c);
2905 if (u->in(0) == unc_ctrl) {
2906 phase->igvn().replace_input_of(u, 0, c);
2907 }
2908 uses.push(u);
2909 }
2910 }
2911 }
2912
2913 Node* new_ctrl = unc_ctrl;
2914
2915 Node* mem = in(Memory);
2916 Node* old_mem = mem;
2917
2918 Node* mem_ctrl = NULL;
2919 int alias = phase->C->get_alias_index(adr_type());
2920 mem = dom_mem(mem, mem_ctrl, this, new_ctrl, alias, phase);
2921 if (mem == NULL) {
2922 return;
2923 }
2924
2925 Node* proj = find_out_with(Op_ShenandoahWBMemProj);
2926 if (!fix_mem_phis(mem, mem_ctrl, new_ctrl, alias, phase)) {
2927 return;
2928 }
2929
2930 assert(mem == old_mem || memory_dominates_all_paths(mem, new_ctrl, alias, phase), "can't fix the memory graph");
2931 phase->set_ctrl_and_loop(this, new_ctrl);
2932 if (in(Control) != NULL) {
2933 phase->igvn().replace_input_of(this, Control, new_ctrl);
2934 }
2935 disconnect_barrier_mem(this, phase->igvn());
2936 fix_memory_uses(mem, this, proj, new_ctrl, phase->C->get_alias_index(adr_type()), phase);
2937 assert(proj->outcnt() > 0, "disconnected write barrier");
2938 phase->igvn().replace_input_of(this, Memory, mem);
2939 phase->set_ctrl_and_loop(proj, new_ctrl);
2940 }
2941 }
2942
2943 void ShenandoahWriteBarrierNode::pin_and_expand_helper(PhaseIdealLoop* phase) {
2944 Node* val = in(ValueIn);
2945 CallStaticJavaNode* unc = pin_and_expand_null_check(phase->igvn());
2946 Node* rep = this;
2947 Node* ctrl = phase->get_ctrl(this);
2948 if (unc != NULL && val->in(0) == ctrl) {
2949 Node* unc_ctrl = val->in(0);
2950 IfNode* other_iff = unc_ctrl->unique_ctrl_out()->as_If();
2951 ProjNode* other_unc_ctrl = other_iff->proj_out(1);
2952 Node* cast = other_unc_ctrl->find_out_with(Op_CastPP);
2953 assert(cast != NULL, "missing cast");
2954 assert(cast->in(1) == this, "bad cast");
2955 assert(other_unc_ctrl->is_uncommon_trap_if_pattern(Deoptimization::Reason_none) == unc, "broken");
2956 rep = cast;
2957 }
2958
2959 // Replace all uses of barrier's input that are dominated by ctrl
2960 // with the value returned by the barrier: no need to keep both
2961 // live.
2962 for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) {
2963 Node* u = val->fast_out(i);
2964 if (u != this) {
2965 if (u->is_Phi()) {
2966 int nb = 0;
2967 for (uint j = 1; j < u->req(); j++) {
2968 if (u->in(j) == val) {
2969 Node* c = u->in(0)->in(j);
2970 if (phase->is_dominator(ctrl, c)) {
2971 phase->igvn().replace_input_of(u, j, rep);
2972 nb++;
2973 }
2974 }
2975 }
2976 if (nb > 0) {
2977 imax -= nb;
2978 --i;
2979 }
2980 } else {
2981 Node* c = phase->ctrl_or_self(u);
2982 if (is_dominator(ctrl, c, this, u, phase)) {
2983 phase->igvn().rehash_node_delayed(u);
2984 int nb = u->replace_edge(val, rep);
2985 assert(nb > 0, "no update?");
2986 --i, imax -= nb;
2987 }
2988 }
2989 }
2990 }
2991 }
2992
2993 Node* ShenandoahWriteBarrierNode::pick_phi(Node* phi1, Node* phi2, Node_Stack& phis, VectorSet& visited, PhaseIdealLoop* phase) {
2994 assert(phis.size() == 0, "stack needs to be empty");
2995 uint i = 1;
2996 int phi_dominates = -1;
2997 for (;;) {
2998 assert(phi1->req() == phi2->req(), "strange pair of phis");
2999 assert(phis.size() % 2 == 0, "");
3000 Node* in1 = phi1->in(i);
3001 Node* in2 = phi2->in(i);
3002
3003 if (in1->is_MergeMem()) {
3004 in1 = in1->as_MergeMem()->base_memory();
3005 }
3006 if (in2->is_MergeMem()) {
3007 in2 = in2->as_MergeMem()->base_memory();
3008 }
3009
3010 if (in1 == in2) {
3011 //continue
3012 } else if (in1->is_Phi() && in2->is_Phi() && in1->in(0) == in2->in(0)) {
3013 assert(!visited.test_set(in1->_idx), "no loop");
3014 assert(!visited.test_set(in2->_idx), "no loop");
3015 phis.push(phi1, i+1);
3016 phis.push(phi2, i+1);
3017 phi1 = in1;
3018 phi2 = in2;
3019 i = 1;
3020 } else {
3021 Node* in1_c = phase->get_ctrl(in1);
3022 Node* in2_c = phase->get_ctrl(in2);
3023 if (is_dominator(in1_c, in2_c, in1, in2, phase)) {
3024 assert(!is_dominator(in2_c, in1_c, in2, in1, phase), "one has to dominate the other");
3025 assert(phi_dominates == -1 || phi_dominates == 1, "all inputs must dominate");
3026 phi_dominates = 1;
3027 } else {
3028 assert(is_dominator(in2_c, in1_c, in2, in1, phase), "one must dominate the other");
3029 assert(!is_dominator(in1_c, in2_c, in1, in2, phase), "one has to dominate the other");
3030 assert(phi_dominates == -1 || phi_dominates == 2, "all inputs must dominate");
3031 phi_dominates = 2;
3032 }
3033 }
3034 i++;
3035
3036 while (i >= phi1->req() && phis.size() > 0) {
3037 i = phis.index();
3038 phi2 = phis.node();
3039 phis.pop();
3040 phi1 = phis.node();
3041 phis.pop();
3042 }
3043
3044 if (i >= phi1->req() && phis.size() == 0) {
3045 Node* phi = NULL;
3046 if (phi_dominates == 1) {
3047 return phi2;
3048 } else if (phi_dominates == 2) {
3049 return phi1;
3050 } else {
3051 return phi1;
3052 }
3053 }
3054 }
3055 return NULL;
3056 }
3057
3058 bool ShenandoahWriteBarrierNode::mem_is_valid(Node* m, Node* c, PhaseIdealLoop* phase) {
3059 return m != NULL && get_ctrl(m, phase) == c;
3060 }
3061
3062 Node* ShenandoahWriteBarrierNode::find_raw_mem(Node* ctrl, Node* n, const Node_List& memory_nodes, PhaseIdealLoop* phase) {
3063 assert(n == NULL || phase->ctrl_or_self(n) == ctrl, "");
3064 Node* raw_mem = memory_nodes[ctrl->_idx];
3065 Node* c = ctrl;
3066 while (!mem_is_valid(raw_mem, c, phase) &&
3067 (!c->is_CatchProj() || raw_mem == NULL || c->in(0)->in(0)->in(0) != get_ctrl(raw_mem, phase))) {
3068 c = phase->idom(c);
3069 raw_mem = memory_nodes[c->_idx];
3070 }
3071 if (n != NULL && mem_is_valid(raw_mem, c, phase)) {
3072 while (!is_dominator_same_ctrl(c, raw_mem, n, phase) && phase->ctrl_or_self(raw_mem) == ctrl) {
3073 raw_mem = next_mem(raw_mem, Compile::AliasIdxRaw);
3074 }
3075 if (raw_mem->is_MergeMem()) {
3076 raw_mem = raw_mem->as_MergeMem()->memory_at(Compile::AliasIdxRaw);
3077 }
3078 if (!mem_is_valid(raw_mem, c, phase)) {
3079 do {
3080 c = phase->idom(c);
3081 raw_mem = memory_nodes[c->_idx];
3082 } while (!mem_is_valid(raw_mem, c, phase) &&
3083 (!c->is_CatchProj() || raw_mem == NULL || c->in(0)->in(0)->in(0) != get_ctrl(raw_mem, phase)));
3084 }
3085 }
3086 assert(raw_mem->bottom_type() == Type::MEMORY, "");
3087 return raw_mem;
3088 }
3089
3090 Node* ShenandoahWriteBarrierNode::find_bottom_mem(Node* ctrl, PhaseIdealLoop* phase) {
3091 Node* mem = NULL;
3092 Node* c = ctrl;
3093 do {
3094 if (c->is_Region()) {
3095 Node* phi_bottom = NULL;
3096 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
3097 Node* u = c->fast_out(i);
3098 if (u->is_Phi() && u->bottom_type() == Type::MEMORY) {
3099 if (u->adr_type() == TypePtr::BOTTOM) {
3100 if (phi_bottom != NULL) {
3101 phi_bottom = NodeSentinel;
3102 } else {
3103 phi_bottom = u;
3104 }
3105 }
3106 }
3107 }
3108 if (phi_bottom != NULL) {
3109 if (phi_bottom != NodeSentinel) {
3110 mem = phi_bottom;
3111 } else {
3112 Node* phi = NULL;
3113 ResourceMark rm;
3114 Node_Stack phis(0);
3115 VectorSet visited(Thread::current()->resource_area());
3116 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
3117 Node* u = c->fast_out(i);
3118 if (u->is_Phi() && u->bottom_type() == Type::MEMORY && u->adr_type() == TypePtr::BOTTOM) {
3119 if (phi == NULL) {
3120 phi = u;
3121 } else {
3122 phi = pick_phi(phi, u, phis, visited, phase);
3123 }
3124 }
3125 }
3126 mem = phi;
3127 }
3128 }
3129 } else {
3130 if (c->is_Call() && c->as_Call()->adr_type() != NULL) {
3131 CallProjections projs;
3132 c->as_Call()->extract_projections(&projs, true, false);
3133 if (projs.fallthrough_memproj != NULL) {
3134 if (projs.fallthrough_memproj->adr_type() == TypePtr::BOTTOM) {
3135 if (projs.catchall_memproj == NULL) {
3136 mem = projs.fallthrough_memproj;
3137 } else {
3138 if (phase->is_dominator(projs.fallthrough_catchproj, ctrl)) {
3139 mem = projs.fallthrough_memproj;
3140 } else {
3141 assert(phase->is_dominator(projs.catchall_catchproj, ctrl), "one proj must dominate barrier");
3142 mem = projs.catchall_memproj;
3143 }
3144 }
3145 }
3146 } else {
3147 Node* proj = c->as_Call()->proj_out(TypeFunc::Memory);
3148 if (proj != NULL &&
3149 proj->adr_type() == TypePtr::BOTTOM) {
3150 mem = proj;
3151 }
3152 }
3153 } else {
3154 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
3155 Node* u = c->fast_out(i);
3156 if (u->is_Proj() &&
3157 u->bottom_type() == Type::MEMORY &&
3158 u->adr_type() == TypePtr::BOTTOM) {
3159 assert(c->is_SafePoint() || c->is_MemBar() || c->is_Start(), "");
3160 assert(mem == NULL, "only one proj");
3161 mem = u;
3162 }
3163 }
3164 assert(!c->is_Call() || c->as_Call()->adr_type() != NULL || mem == NULL, "no mem projection expected");
3165 }
3166 }
3167 c = phase->idom(c);
3168 } while (mem == NULL);
3169 return mem;
3170 }
3171
3172 void ShenandoahWriteBarrierNode::follow_barrier_uses(Node* n, Node* ctrl, Unique_Node_List& uses, PhaseIdealLoop* phase) {
3173 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
3174 Node* u = n->fast_out(i);
3175 if (!u->is_CFG() && phase->get_ctrl(u) == ctrl && (!u->is_Phi() || !u->in(0)->is_Loop() || u->in(LoopNode::LoopBackControl) != n)) {
3176 uses.push(u);
3177 }
3178 }
3179 }
3180
3181 Node* ShenandoahWriteBarrierNode::get_ctrl(Node* n, PhaseIdealLoop* phase) {
3182 Node* c = phase->get_ctrl(n);
3183 if (n->is_Proj() && n->in(0)->is_Call()) {
3184 assert(c == n->in(0), "");
3185 CallNode* call = c->as_Call();
3186 CallProjections projs;
3187 call->extract_projections(&projs, true, false);
3188 if (projs.catchall_memproj != NULL) {
3189 if (projs.fallthrough_memproj == n) {
3190 c = projs.fallthrough_catchproj;
3191 } else {
3192 assert(projs.catchall_memproj == n, "");
3193 c = projs.catchall_catchproj;
3194 }
3195 }
3196 }
3197 return c;
3198 }
3199
3200 Node* ShenandoahWriteBarrierNode::ctrl_or_self(Node* n, PhaseIdealLoop* phase) {
3201 if (phase->has_ctrl(n))
3202 return get_ctrl(n, phase);
3203 else {
3204 assert (n->is_CFG(), "must be a CFG node");
3205 return n;
3206 }
3207 }
3208
3209 #ifdef ASSERT
3210 static bool has_never_branch(Node* root) {
3211 for (uint i = 1; i < root->req(); i++) {
3212 Node* in = root->in(i);
3213 if (in != NULL && in->Opcode() == Op_Halt && in->in(0)->is_Proj() && in->in(0)->in(0)->Opcode() == Op_NeverBranch) {
3214 return true;
3215 }
3216 }
3217 return false;
3218 }
3219 #endif
3220
3221 void ShenandoahWriteBarrierNode::collect_memory_nodes(int alias, Node_List& memory_nodes, PhaseIdealLoop* phase) {
3222 Node_Stack stack(0);
3223 VectorSet visited(Thread::current()->resource_area());
3224 Node_List regions;
3225
3226 // Walk the raw memory graph and create a mapping from CFG node to
3227 // memory node. Exclude phis for now.
3228 stack.push(phase->C->root(), 1);
3229 do {
3230 Node* n = stack.node();
3231 int opc = n->Opcode();
3232 uint i = stack.index();
3233 if (i < n->req()) {
3234 Node* mem = NULL;
3235 if (opc == Op_Root) {
3236 Node* in = n->in(i);
3237 int in_opc = in->Opcode();
3238 if (in_opc == Op_Return || in_opc == Op_Rethrow) {
3239 mem = in->in(TypeFunc::Memory);
3240 } else if (in_opc == Op_Halt) {
3241 if (!in->in(0)->is_Region()) {
3242 Node* proj = in->in(0);
3243 assert(proj->is_Proj(), "");
3244 Node* in = proj->in(0);
3245 assert(in->is_CallStaticJava() || in->Opcode() == Op_NeverBranch || in->Opcode() == Op_Catch || proj->is_IfProj(), "");
3246 if (in->is_CallStaticJava()) {
3247 mem = in->in(TypeFunc::Memory);
3248 } else if (in->Opcode() == Op_Catch) {
3249 Node* call = in->in(0)->in(0);
3250 assert(call->is_Call(), "");
3251 mem = call->in(TypeFunc::Memory);
3252 }
3253 }
3254 } else {
3255 #ifdef ASSERT
3256 n->dump();
3257 in->dump();
3258 #endif
3259 ShouldNotReachHere();
3260 }
3261 } else {
3262 assert(n->is_Phi() && n->bottom_type() == Type::MEMORY, "");
3263 assert(n->adr_type() == TypePtr::BOTTOM || phase->C->get_alias_index(n->adr_type()) == alias, "");
3264 mem = n->in(i);
3265 }
3266 i++;
3267 stack.set_index(i);
3268 if (mem == NULL) {
3269 continue;
3270 }
3271 for (;;) {
3272 if (visited.test_set(mem->_idx) || mem->is_Start()) {
3273 break;
3274 }
3275 if (mem->is_Phi()) {
3276 stack.push(mem, 2);
3277 mem = mem->in(1);
3278 } else if (mem->is_Proj()) {
3279 stack.push(mem, mem->req());
3280 mem = mem->in(0);
3281 } else if (mem->is_SafePoint() || mem->is_MemBar()) {
3282 mem = mem->in(TypeFunc::Memory);
3283 } else if (mem->is_MergeMem()) {
3284 mem = mem->as_MergeMem()->memory_at(alias);
3285 } else if (mem->is_Store() || mem->is_LoadStore() || mem->is_ClearArray()) {
3286 stack.push(mem, mem->req());
3287 mem = mem->in(MemNode::Memory);
3288 } else {
3289 #ifdef ASSERT
3290 mem->dump();
3291 #endif
3292 ShouldNotReachHere();
3293 }
3294 }
3295 } else {
3296 if (n->is_Phi()) {
3297 // Nothing
3298 } else if (!n->is_Root()) {
3299 Node* c = get_ctrl(n, phase);
3300 memory_nodes.map(c->_idx, n);
3301 }
3302 stack.pop();
3303 }
3304 } while(stack.is_nonempty());
3305
3306 // Iterate over CFG nodes in rpo and propagate memory state to
3307 // compute memory state at regions, creating new phis if needed.
3308 Node_List rpo_list;
3309 visited.Clear();
3310 phase->rpo(phase->C->root(), stack, visited, rpo_list);
3311 Node* root = rpo_list.pop();
3312 assert(root == phase->C->root(), "");
3313
3314 const bool trace = false;
3315 #ifdef ASSERT
3316 if (trace) {
3317 for (int i = rpo_list.size() - 1; i >= 0; i--) {
3318 Node* c = rpo_list.at(i);
3319 if (memory_nodes[c->_idx] != NULL) {
3320 tty->print("X %d", c->_idx); memory_nodes[c->_idx]->dump();
3321 }
3322 }
3323 }
3324 #endif
3325 uint last = phase->C->unique();
3326
3327 #ifdef ASSERT
3328 uint8_t max_depth = 0;
3329 for (LoopTreeIterator iter(phase->ltree_root()); !iter.done(); iter.next()) {
3330 IdealLoopTree* lpt = iter.current();
3331 max_depth = MAX2(max_depth, lpt->_nest);
3332 }
3333 #endif
3334
3335 bool progress = true;
3336 int iteration = 0;
3337 Node_List dead_phis;
3338 while (progress) {
3339 progress = false;
3340 iteration++;
3341 assert(iteration <= 2+max_depth || phase->C->has_irreducible_loop(), "");
3342 if (trace) { tty->print_cr("XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"); }
3343 IdealLoopTree* last_updated_ilt = NULL;
3344 for (int i = rpo_list.size() - 1; i >= 0; i--) {
3345 Node* c = rpo_list.at(i);
3346
3347 Node* prev_mem = memory_nodes[c->_idx];
3348 if (c->is_Region()) {
3349 Node* prev_region = regions[c->_idx];
3350 Node* unique = NULL;
3351 for (uint j = 1; j < c->req() && unique != NodeSentinel; j++) {
3352 Node* m = memory_nodes[c->in(j)->_idx];
3353 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");
3354 if (m != NULL) {
3355 if (m == prev_region && ((c->is_Loop() && j == LoopNode::LoopBackControl) || (prev_region->is_Phi() && prev_region->in(0) == c))) {
3356 assert(c->is_Loop() && j == LoopNode::LoopBackControl || phase->C->has_irreducible_loop(), "");
3357 // continue
3358 } else if (unique == NULL) {
3359 unique = m;
3360 } else if (m == unique) {
3361 // continue
3362 } else {
3363 unique = NodeSentinel;
3364 }
3365 }
3366 }
3367 assert(unique != NULL, "empty phi???");
3368 if (unique != NodeSentinel) {
3369 if (prev_region != NULL && prev_region->is_Phi() && prev_region->in(0) == c) {
3370 dead_phis.push(prev_region);
3371 }
3372 regions.map(c->_idx, unique);
3373 } else {
3374 Node* phi = NULL;
3375 if (prev_region != NULL && prev_region->is_Phi() && prev_region->in(0) == c && prev_region->_idx >= last) {
3376 phi = prev_region;
3377 for (uint k = 1; k < c->req(); k++) {
3378 Node* m = memory_nodes[c->in(k)->_idx];
3379 assert(m != NULL, "expect memory state");
3380 phi->set_req(k, m);
3381 }
3382 } else {
3383 for (DUIterator_Fast jmax, j = c->fast_outs(jmax); j < jmax && phi == NULL; j++) {
3384 Node* u = c->fast_out(j);
3385 if (u->is_Phi() && u->bottom_type() == Type::MEMORY &&
3386 (u->adr_type() == TypePtr::BOTTOM || phase->C->get_alias_index(u->adr_type()) == alias)) {
3387 phi = u;
3388 for (uint k = 1; k < c->req() && phi != NULL; k++) {
3389 Node* m = memory_nodes[c->in(k)->_idx];
3390 assert(m != NULL, "expect memory state");
3391 if (u->in(k) != m) {
3392 phi = NULL;
3393 }
3394 }
3395 }
3396 }
3397 if (phi == NULL) {
3398 phi = new PhiNode(c, Type::MEMORY, phase->C->get_adr_type(alias));
3399 for (uint k = 1; k < c->req(); k++) {
3400 Node* m = memory_nodes[c->in(k)->_idx];
3401 assert(m != NULL, "expect memory state");
3402 phi->init_req(k, m);
3403 }
3404 }
3405 }
3406 assert(phi != NULL, "");
3407 regions.map(c->_idx, phi);
3408 }
3409 Node* current_region = regions[c->_idx];
3410 if (current_region != prev_region) {
3411 progress = true;
3412 if (prev_region == prev_mem) {
3413 memory_nodes.map(c->_idx, current_region);
3414 }
3415 }
3416 } else if (prev_mem == NULL || prev_mem->is_Phi() || ctrl_or_self(prev_mem, phase) != c) {
3417 Node* m = memory_nodes[phase->idom(c)->_idx];
3418 assert(m != NULL, "expect memory state");
3419 if (m != prev_mem) {
3420 memory_nodes.map(c->_idx, m);
3421 progress = true;
3422 }
3423 }
3424 #ifdef ASSERT
3425 if (trace) { tty->print("X %d", c->_idx); memory_nodes[c->_idx]->dump(); }
3426 #endif
3427 }
3428 }
3429
3430 // Replace existing phi with computed memory state for that region
3431 // if different (could be a new phi or a dominating memory node if
3432 // that phi was found to be useless).
3433 while (dead_phis.size() > 0) {
3434 Node* n = dead_phis.pop();
3435 n->replace_by(phase->C->top());
3436 n->destruct();
3437 }
3438 for (int i = rpo_list.size() - 1; i >= 0; i--) {
3439 Node* c = rpo_list.at(i);
3440 if (c->is_Region()) {
3441 Node* n = regions[c->_idx];
3442 if (n->is_Phi() && n->_idx >= last && n->in(0) == c) {
3443 phase->register_new_node(n, c);
3444 }
3445 }
3446 }
3447 for (int i = rpo_list.size() - 1; i >= 0; i--) {
3448 Node* c = rpo_list.at(i);
3449 if (c->is_Region()) {
3450 Node* n = regions[c->_idx];
3451 for (DUIterator_Fast imax, i = c->fast_outs(imax); i < imax; i++) {
3452 Node* u = c->fast_out(i);
3453 if (u->is_Phi() && u->bottom_type() == Type::MEMORY &&
3454 u != n) {
3455 if (u->adr_type() == TypePtr::BOTTOM) {
3456 fix_memory_uses(u, n, n, c, alias, phase);
3457 } else if (phase->C->get_alias_index(u->adr_type()) == alias) {
3458 phase->lazy_replace(u, n);
3459 --i; --imax;
3460 }
3461 }
3462 }
3463 }
3464 }
3465 }
3466
3467 void ShenandoahWriteBarrierNode::fix_raw_mem(Node* ctrl, Node* region, Node* raw_mem, Node* raw_mem_for_ctrl, Node* raw_mem_phi,
3468 Node_List& memory_nodes, Unique_Node_List& uses, PhaseIdealLoop* phase) {
3469 const bool trace = false;
3470 DEBUG_ONLY(if (trace) { tty->print("ZZZ control is"); ctrl->dump(); });
3471 DEBUG_ONLY(if (trace) { tty->print("ZZZ mem is"); raw_mem->dump(); });
3472 GrowableArray<Node*> phis;
3473 if (raw_mem_for_ctrl != raw_mem) {
3474 Node* old = raw_mem_for_ctrl;
3475 Node* prev = NULL;
3476 while (old != raw_mem) {
3477 assert(old->is_Store() || old->is_LoadStore() || old->is_ClearArray(), "");
3478 prev = old;
3479 old = old->in(MemNode::Memory);
3480 }
3481 assert(prev != NULL, "");
3482 memory_nodes.map(ctrl->_idx, raw_mem);
3483 memory_nodes.map(region->_idx, raw_mem_for_ctrl);
3484 phase->igvn().replace_input_of(prev, MemNode::Memory, raw_mem_phi);
3485 } else {
3486 memory_nodes.map(region->_idx, raw_mem_phi);
3487 uses.clear();
3488 uses.push(region);
3489 for(uint next = 0; next < uses.size(); next++ ) {
3490 Node *n = uses.at(next);
3491 assert(n->is_CFG(), "");
3492 DEBUG_ONLY(if (trace) { tty->print("ZZZ ctrl"); n->dump(); });
3493 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
3494 Node* u = n->fast_out(i);
3495 if (!u->is_Root() && u->is_CFG() && u != n) {
3496 Node* m = memory_nodes[u->_idx];
3497 if (u->is_Region() && !has_mem_phi(phase->C, u, Compile::AliasIdxRaw) &&
3498 u->unique_ctrl_out()->Opcode() != Op_Halt) {
3499 DEBUG_ONLY(if (trace) { tty->print("ZZZ region"); u->dump(); });
3500 DEBUG_ONLY(if (trace && m != NULL) { tty->print("ZZZ mem"); m->dump(); });
3501
3502 if (!mem_is_valid(m, u, phase) || !m->is_Phi()) {
3503 bool push = true;
3504 bool create_phi = true;
3505 if (phase->is_dominator(region, u)) {
3506 create_phi = false;
3507 } else if (!phase->C->has_irreducible_loop()) {
3508 IdealLoopTree* loop = phase->get_loop(ctrl);
3509 bool do_check = true;
3510 IdealLoopTree* l = loop;
3511 create_phi = false;
3512 while (l != phase->ltree_root()) {
3513 if (phase->is_dominator(l->_head, u) && phase->is_dominator(phase->idom(u), l->_head)) {
3514 create_phi = true;
3515 do_check = false;
3516 break;
3517 }
3518 l = l->_parent;
3519 }
3520
3521 if (do_check) {
3522 assert(!create_phi, "");
3523 IdealLoopTree* u_loop = phase->get_loop(u);
3524 if (u_loop != phase->ltree_root() && u_loop->is_member(loop)) {
3525 Node* c = ctrl;
3526 while (!phase->is_dominator(c, u_loop->tail())) {
3527 c = phase->idom(c);
3528 }
3529 if (!phase->is_dominator(c, u)) {
3530 do_check = false;
3531 }
3532 }
3533 }
3534
3535 if (do_check && phase->is_dominator(phase->idom(u), region)) {
3536 create_phi = true;
3537 }
3538 }
3539 if (create_phi) {
3540 Node* phi = new PhiNode(u, Type::MEMORY, TypeRawPtr::BOTTOM);
3541 phase->register_new_node(phi, u);
3542 phis.push(phi);
3543 DEBUG_ONLY(if (trace) { tty->print("ZZZ new phi"); phi->dump(); });
3544 if (!mem_is_valid(m, u, phase)) {
3545 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting mem"); phi->dump(); });
3546 memory_nodes.map(u->_idx, phi);
3547 } else {
3548 DEBUG_ONLY(if (trace) { tty->print("ZZZ NOT setting mem"); m->dump(); });
3549 for (;;) {
3550 assert(m->is_Mem() || m->is_LoadStore() || m->is_Proj() /*|| m->is_MergeMem()*/, "");
3551 Node* next = NULL;
3552 if (m->is_Proj()) {
3553 next = m->in(0);
3554 } else {
3555 next = m->in(MemNode::Memory);
3556 }
3557 if (phase->get_ctrl(next) != u) {
3558 break;
3559 }
3560 if (next->is_MergeMem()) {
3561 assert(phase->get_ctrl(next->as_MergeMem()->memory_at(Compile::AliasIdxRaw)) != u, "");
3562 break;
3563 }
3564 if (next->is_Phi()) {
3565 assert(next->adr_type() == TypePtr::BOTTOM && next->in(0) == u, "");
3566 break;
3567 }
3568 m = next;
3569 }
3570
3571 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting to phi"); m->dump(); });
3572 assert(m->is_Mem() || m->is_LoadStore(), "");
3573 phase->igvn().replace_input_of(m, MemNode::Memory, phi);
3574 push = false;
3575 }
3576 } else {
3577 DEBUG_ONLY(if (trace) { tty->print("ZZZ skipping region"); u->dump(); });
3578 }
3579 if (push) {
3580 uses.push(u);
3581 }
3582 }
3583 } else if (!mem_is_valid(m, u, phase) &&
3584 !(u->Opcode() == Op_CProj && u->in(0)->Opcode() == Op_NeverBranch && u->as_Proj()->_con == 1)) {
3585 uses.push(u);
3586 }
3587 }
3588 }
3589 }
3590 for (int i = 0; i < phis.length(); i++) {
3591 Node* n = phis.at(i);
3592 Node* r = n->in(0);
3593 DEBUG_ONLY(if (trace) { tty->print("ZZZ fixing new phi"); n->dump(); });
3594 for (uint j = 1; j < n->req(); j++) {
3595 Node* m = find_raw_mem(r->in(j), NULL, memory_nodes, phase);
3596 phase->igvn().replace_input_of(n, j, m);
3597 DEBUG_ONLY(if (trace) { tty->print("ZZZ fixing new phi: %d", j); m->dump(); });
3598 }
3599 }
3600 }
3601 uint last = phase->C->unique();
3602 MergeMemNode* mm = NULL;
3603 int alias = Compile::AliasIdxRaw;
3604 DEBUG_ONLY(if (trace) { tty->print("ZZZ raw mem is"); raw_mem->dump(); });
3605 for (DUIterator i = raw_mem->outs(); raw_mem->has_out(i); i++) {
3606 Node* u = raw_mem->out(i);
3607 if (u->_idx < last) {
3608 if (u->is_Mem()) {
3609 if (phase->C->get_alias_index(u->adr_type()) == alias) {
3610 Node* m = find_raw_mem(phase->get_ctrl(u), u, memory_nodes, phase);
3611 if (m != raw_mem) {
3612 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
3613 phase->igvn().replace_input_of(u, MemNode::Memory, m);
3614 --i;
3615 }
3616 }
3617 } else if (u->is_MergeMem()) {
3618 MergeMemNode* u_mm = u->as_MergeMem();
3619 if (u_mm->memory_at(alias) == raw_mem) {
3620 MergeMemNode* newmm = NULL;
3621 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
3622 Node* uu = u->fast_out(j);
3623 assert(!uu->is_MergeMem(), "chain of MergeMems?");
3624 if (uu->is_Phi()) {
3625 assert(uu->adr_type() == TypePtr::BOTTOM, "");
3626 Node* region = uu->in(0);
3627 int nb = 0;
3628 for (uint k = 1; k < uu->req(); k++) {
3629 if (uu->in(k) == u) {
3630 Node* m = find_raw_mem(region->in(k), NULL, memory_nodes, phase);
3631 if (m != raw_mem) {
3632 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of phi %d", k); uu->dump(); });
3633 if (newmm == NULL || 1) {
3634 newmm = clone_merge_mem(u, raw_mem, alias, m, phase->ctrl_or_self(m), i, phase);
3635 }
3636 if (newmm != u) {
3637 phase->igvn().replace_input_of(uu, k, newmm);
3638 nb++;
3639 --jmax;
3640 }
3641 }
3642 }
3643 }
3644 if (nb > 0) {
3645 --j;
3646 }
3647 } else {
3648 Node* m = find_raw_mem(phase->ctrl_or_self(uu), uu, memory_nodes, phase);
3649 if (m != raw_mem) {
3650 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); uu->dump(); });
3651 if (newmm == NULL || 1) {
3652 newmm = clone_merge_mem(u, raw_mem, alias, m, phase->ctrl_or_self(m), i, phase);
3653 }
3654 if (newmm != u) {
3655 phase->igvn().replace_input_of(uu, uu->find_edge(u), newmm);
3656 --j, --jmax;
3657 }
3658 }
3659 }
3660 }
3661 }
3662 } else if (u->is_Phi()) {
3663 assert(u->bottom_type() == Type::MEMORY, "what else?");
3664 if (u->adr_type() == TypeRawPtr::BOTTOM || u->adr_type() == TypePtr::BOTTOM) {
3665 Node* region = u->in(0);
3666 bool replaced = false;
3667 for (uint j = 1; j < u->req(); j++) {
3668 if (u->in(j) == raw_mem) {
3669 Node* m = find_raw_mem(region->in(j), NULL, memory_nodes, phase);
3670 Node* nnew = m;
3671 if (m != raw_mem) {
3672 if (u->adr_type() == TypePtr::BOTTOM) {
3673 if (mm == NULL || 1) {
3674 mm = allocate_merge_mem(raw_mem, alias, m, phase->ctrl_or_self(m), phase);
3675 }
3676 nnew = mm;
3677 }
3678 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of phi %d", j); u->dump(); });
3679 phase->igvn().replace_input_of(u, j, nnew);
3680 replaced = true;
3681 }
3682 }
3683 }
3684 if (replaced) {
3685 --i;
3686 }
3687 }
3688 } else if ((u->adr_type() == TypePtr::BOTTOM && u->Opcode() != Op_StrInflatedCopy) ||
3689 u->adr_type() == NULL) {
3690 assert(u->adr_type() != NULL ||
3691 u->Opcode() == Op_Rethrow ||
3692 u->Opcode() == Op_Return ||
3693 u->Opcode() == Op_SafePoint ||
3694 (u->is_CallStaticJava() && u->as_CallStaticJava()->uncommon_trap_request() != 0) ||
3695 (u->is_CallStaticJava() && u->as_CallStaticJava()->_entry_point == OptoRuntime::rethrow_stub()) ||
3696 u->Opcode() == Op_CallLeaf, "");
3697 Node* m = find_raw_mem(phase->ctrl_or_self(u), u, memory_nodes, phase);
3698 if (m != raw_mem) {
3699 if (mm == NULL || 1) {
3700 mm = allocate_merge_mem(raw_mem, alias, m, phase->get_ctrl(m), phase);
3701 }
3702 phase->igvn().replace_input_of(u, u->find_edge(raw_mem), mm);
3703 --i;
3704 }
3705 } else if (phase->C->get_alias_index(u->adr_type()) == alias) {
3706 Node* m = find_raw_mem(phase->ctrl_or_self(u), u, memory_nodes, phase);
3707 if (m != raw_mem) {
3708 DEBUG_ONLY(if (trace) { tty->print("ZZZ setting memory of use"); u->dump(); });
3709 phase->igvn().replace_input_of(u, u->find_edge(raw_mem), m);
3710 --i;
3711 }
3712 }
3713 }
3714 }
3715 #ifdef ASSERT
3716 assert(raw_mem_phi->outcnt() > 0, "");
3717 for (int i = 0; i < phis.length(); i++) {
3718 Node* n = phis.at(i);
3719 assert(n->outcnt() > 0, "new phi must have uses now");
3720 }
3721 #endif
3722 }
3723
3724 void ShenandoahWriteBarrierNode::test_heap_stable(Node* ctrl, Node* raw_mem, Node*& gc_state, Node*& heap_stable,
3725 Node*& heap_not_stable, PhaseIdealLoop* phase) {
3726 IdealLoopTree *loop = phase->get_loop(ctrl);
3727 Node* thread = new ThreadLocalNode();
3728 phase->register_new_node(thread, ctrl);
3729 Node* offset = phase->igvn().MakeConX(in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
3730 phase->set_ctrl(offset, phase->C->root());
3731 Node* gc_state_addr = new AddPNode(phase->C->top(), thread, offset);
3732 phase->register_new_node(gc_state_addr, ctrl);
3733 uint gc_state_idx = Compile::AliasIdxRaw;
3734 const TypePtr* gc_state_adr_type = NULL; // debug-mode-only argument
3735 debug_only(gc_state_adr_type = phase->C->get_adr_type(gc_state_idx));
3736
3737 gc_state = new LoadBNode(ctrl, raw_mem, gc_state_addr, gc_state_adr_type, TypeInt::BYTE, MemNode::unordered);
3738 phase->register_new_node(gc_state, ctrl);
3739
3740 Node* heap_stable_cmp = new CmpINode(gc_state, phase->igvn().zerocon(T_INT));
3741 phase->register_new_node(heap_stable_cmp, ctrl);
3742 Node* heap_stable_test = new BoolNode(heap_stable_cmp, BoolTest::ne);
3743 phase->register_new_node(heap_stable_test, ctrl);
3744 IfNode* heap_stable_iff = new IfNode(ctrl, heap_stable_test, PROB_UNLIKELY(0.999), COUNT_UNKNOWN);
3745 phase->register_control(heap_stable_iff, loop, ctrl);
3746
3747 heap_stable = new IfFalseNode(heap_stable_iff);
3748 phase->register_control(heap_stable, loop, heap_stable_iff);
3749 heap_not_stable = new IfTrueNode(heap_stable_iff);
3750 phase->register_control(heap_not_stable, loop, heap_stable_iff);
3751
3752 assert(is_heap_stable_test(heap_stable_iff), "Should match the shape");
3753 }
3754
3755
3756 void ShenandoahWriteBarrierNode::test_evacuation_in_progress(Node* ctrl, int alias, Node*& raw_mem, Node*& wb_mem,
3757 Node*& evac_in_progress, Node*& evac_not_in_progress, Node*& heap_stable,
3758 PhaseIdealLoop* phase) {
3759 IdealLoopTree *loop = phase->get_loop(ctrl);
3760 Node* heap_not_stable = NULL;
3761 Node* unused_gc_state = NULL;
3762
3763 test_heap_stable(ctrl, raw_mem, unused_gc_state, heap_stable, heap_not_stable, phase);
3764
3765 ctrl = heap_not_stable;
3766
3767 Node* thread = new ThreadLocalNode();
3768 phase->register_new_node(thread, ctrl);
3769 Node* offset = phase->igvn().MakeConX(in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
3770 phase->set_ctrl(offset, phase->C->root());
3771 Node* gc_state_addr = new AddPNode(phase->C->top(), thread, offset);
3772 phase->register_new_node(gc_state_addr, ctrl);
3773 uint gc_state_idx = Compile::AliasIdxRaw;
3774 const TypePtr* gc_state_adr_type = NULL; // debug-mode-only argument
3775 debug_only(gc_state_adr_type = phase->C->get_adr_type(gc_state_idx));
3776
3777 Node* gc_state = new LoadBNode(ctrl, raw_mem, gc_state_addr, gc_state_adr_type, TypeInt::BYTE, MemNode::unordered);
3778 phase->register_new_node(gc_state, ctrl);
3779
3780 Node* evacuation_in_progress = new AndINode(gc_state, phase->igvn().intcon(ShenandoahHeap::EVACUATION | ShenandoahHeap::TRAVERSAL));
3781 phase->register_new_node(evacuation_in_progress, ctrl);
3782 Node* evacuation_in_progress_cmp = new CmpINode(evacuation_in_progress, phase->igvn().zerocon(T_INT));
3783 phase->register_new_node(evacuation_in_progress_cmp, ctrl);
3784 Node* evacuation_in_progress_test = new BoolNode(evacuation_in_progress_cmp, BoolTest::ne);
3785 phase->register_new_node(evacuation_in_progress_test, ctrl);
3786 IfNode* evacuation_iff = new IfNode(ctrl, evacuation_in_progress_test, PROB_UNLIKELY(0.999), COUNT_UNKNOWN);
3787 phase->register_control(evacuation_iff, loop, ctrl);
3788
3789 assert(is_evacuation_in_progress_test(evacuation_iff), "Should match the shape");
3790 assert(is_gc_state_load(gc_state), "Should match the shape");
3791
3792 evac_not_in_progress = new IfFalseNode(evacuation_iff);
3793 phase->register_control(evac_not_in_progress, loop, evacuation_iff);
3794 evac_in_progress = new IfTrueNode(evacuation_iff);
3795 phase->register_control(evac_in_progress, loop, evacuation_iff);
3796 }
3797
3798 Node* ShenandoahWriteBarrierNode::clone_null_check(Node*& c, Node* val, Node* unc_ctrl,
3799 Node* unc_region, uint input, PhaseIdealLoop* phase) {
3800 IdealLoopTree *loop = phase->get_loop(c);
3801 Node* iff = unc_ctrl->in(0);
3802 assert(iff->is_If(), "broken");
3803 Node* new_iff = iff->clone();
3804 new_iff->set_req(0, c);
3805 phase->register_control(new_iff, loop, c);
3806 Node* iffalse = new IfFalseNode(new_iff->as_If());
3807 phase->register_control(iffalse, loop, new_iff);
3808 Node* iftrue = new IfTrueNode(new_iff->as_If());
3809 phase->register_control(iftrue, loop, new_iff);
3810 c = iftrue;
3811 const Type *t = phase->igvn().type(val);
3812 assert(val->Opcode() == Op_CastPP, "expect cast to non null here");
3813 Node* uncasted_val = val->in(1);
3814 val = new CastPPNode(uncasted_val, t);
3815 val->init_req(0, c);
3816 phase->register_new_node(val, c);
3817 unc_region->init_req(input, iffalse);
3818 return val;
3819 }
3820
3821 void ShenandoahWriteBarrierNode::fix_null_check(Node* dom, Node* unc, Node* unc_ctrl, Node* unc_region,
3822 Unique_Node_List& uses, PhaseIdealLoop* phase) {
3823 IfNode* iff = unc_ctrl->in(0)->as_If();
3824 Node* proj = iff->proj_out(0);
3825 assert(proj != unc_ctrl, "bad projection");
3826 Node* use = proj->unique_ctrl_out();
3827
3828 assert(use == unc || use->is_Region(), "what else?");
3829
3830 uses.clear();
3831 if (use == unc) {
3832 phase->set_idom(use, unc_region, phase->dom_depth(use));
3833 for (uint i = 1; i < unc->req(); i++) {
3834 Node* n = unc->in(i);
3835 if (phase->has_ctrl(n) && phase->get_ctrl(n) == proj) {
3836 uses.push(n);
3837 }
3838 }
3839 } else {
3840 assert(use->is_Region(), "what else?");
3841 uint idx = 1;
3842 for (; use->in(idx) != proj; idx++);
3843 for (DUIterator_Fast imax, i = use->fast_outs(imax); i < imax; i++) {
3844 Node* u = use->fast_out(i);
3845 if (u->is_Phi() && phase->get_ctrl(u->in(idx)) == proj) {
3846 uses.push(u->in(idx));
3847 }
3848 }
3849 }
3850 for(uint next = 0; next < uses.size(); next++ ) {
3851 Node *n = uses.at(next);
3852 assert(phase->get_ctrl(n) == proj, "bad control");
3853 phase->set_ctrl_and_loop(n, unc_region);
3854 if (n->in(0) == proj) {
3855 phase->igvn().replace_input_of(n, 0, unc_region);
3856 }
3857 for (uint i = 0; i < n->req(); i++) {
3858 Node* m = n->in(i);
3859 if (m != NULL && phase->has_ctrl(m) && phase->get_ctrl(m) == proj) {
3860 uses.push(m);
3861 }
3862 }
3863 }
3864
3865 phase->igvn().rehash_node_delayed(use);
3866 int nb = use->replace_edge(proj, unc_region);
3867 assert(nb == 1, "only use expected");
3868 phase->register_control(unc_region, phase->ltree_root(), dom);
3869 }
3870
3871 void ShenandoahWriteBarrierNode::evacuation_not_in_progress_null_check(Node*& c, Node*& val, Node* unc_ctrl, Node*& unc_region, PhaseIdealLoop* phase) {
3872 if (unc_ctrl != NULL) {
3873 // Clone the null check in this branch to allow implicit null check
3874 unc_region = new RegionNode(3);
3875 val = clone_null_check(c, val, unc_ctrl, unc_region, 1, phase);
3876 }
3877 }
3878
3879 void ShenandoahWriteBarrierNode::evacuation_not_in_progress(Node* c, Node* val, Node* unc_ctrl, Node* raw_mem, Node* wb_mem, Node* region,
3880 Node* val_phi, Node* mem_phi, Node* raw_mem_phi, Node*& unc_region, PhaseIdealLoop* phase) {
3881 evacuation_not_in_progress_null_check(c, val, unc_ctrl, unc_region, phase);
3882 region->init_req(1, c);
3883 if (ShenandoahWriteBarrierRB) {
3884 Node* rbfalse = new ShenandoahReadBarrierNode(c, wb_mem, val);
3885 phase->register_new_node(rbfalse, c);
3886 val_phi->init_req(1, rbfalse);
3887 } else {
3888 val_phi->init_req(1, val);
3889 }
3890 mem_phi->init_req(1, wb_mem);
3891 raw_mem_phi->init_req(1, raw_mem);
3892 }
3893
3894 void ShenandoahWriteBarrierNode::heap_stable(Node* c, Node* val, Node* unc_ctrl, Node* raw_mem, Node* wb_mem, Node* region,
3895 Node* val_phi, Node* mem_phi, Node* raw_mem_phi, Node* unc_region, PhaseIdealLoop* phase) {
3896 region->init_req(1, c);
3897 if (unc_ctrl != NULL) {
3898 val = val->in(1);
3899 }
3900 val_phi->init_req(1, val);
3901 mem_phi->init_req(1, wb_mem);
3902 raw_mem_phi->init_req(1, raw_mem);
3903 }
3904
3905 void ShenandoahWriteBarrierNode::evacuation_in_progress_null_check(Node*& c, Node*& val, Node* evacuation_iff, Node* unc, Node* unc_ctrl,
3906 Node* unc_region, Unique_Node_List& uses, PhaseIdealLoop* phase) {
3907 if (unc != NULL) {
3908 // Clone the null check in this branch to allow implicit null check
3909 val = clone_null_check(c, val, unc_ctrl, unc_region, 2, phase);
3910
3911 fix_null_check(evacuation_iff, unc, unc_ctrl, unc_region, uses, phase);
3912
3913 IfNode* iff = unc_ctrl->in(0)->as_If();
3914 phase->igvn().replace_input_of(iff, 1, phase->igvn().intcon(1));
3915 }
3916 }
3917
3918 void ShenandoahWriteBarrierNode::in_cset_fast_test(Node*& c, Node* rbtrue, Node* raw_mem, Node* wb_mem, Node* region, Node* val_phi, Node* mem_phi,
3919 Node* raw_mem_phi, PhaseIdealLoop* phase) {
3920 if (ShenandoahWriteBarrierCsetTestInIR) {
3921 IdealLoopTree *loop = phase->get_loop(c);
3922 Node* raw_rbtrue = new CastP2XNode(c, rbtrue);
3923 phase->register_new_node(raw_rbtrue, c);
3924 Node* cset_offset = new URShiftXNode(raw_rbtrue, phase->igvn().intcon(ShenandoahHeapRegion::region_size_bytes_shift_jint()));
3925 phase->register_new_node(cset_offset, c);
3926 Node* in_cset_fast_test_base_addr = phase->igvn().makecon(TypeRawPtr::make(ShenandoahHeap::in_cset_fast_test_addr()));
3927 phase->set_ctrl(in_cset_fast_test_base_addr, phase->C->root());
3928 Node* in_cset_fast_test_adr = new AddPNode(phase->C->top(), in_cset_fast_test_base_addr, cset_offset);
3929 phase->register_new_node(in_cset_fast_test_adr, c);
3930 uint in_cset_fast_test_idx = Compile::AliasIdxRaw;
3931 const TypePtr* in_cset_fast_test_adr_type = NULL; // debug-mode-only argument
3932 debug_only(in_cset_fast_test_adr_type = phase->C->get_adr_type(in_cset_fast_test_idx));
3933 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);
3934 phase->register_new_node(in_cset_fast_test_load, c);
3935 Node* in_cset_fast_test_cmp = new CmpINode(in_cset_fast_test_load, phase->igvn().zerocon(T_INT));
3936 phase->register_new_node(in_cset_fast_test_cmp, c);
3937 Node* in_cset_fast_test_test = new BoolNode(in_cset_fast_test_cmp, BoolTest::ne);
3938 phase->register_new_node(in_cset_fast_test_test, c);
3939 IfNode* in_cset_fast_test_iff = new IfNode(c, in_cset_fast_test_test, PROB_UNLIKELY(0.999), COUNT_UNKNOWN);
3940 phase->register_control(in_cset_fast_test_iff, loop, c);
3941
3942 Node* in_cset_fast_test_success = new IfFalseNode(in_cset_fast_test_iff);
3943 phase->register_control(in_cset_fast_test_success, loop, in_cset_fast_test_iff);
3944
3945 region->init_req(3, in_cset_fast_test_success);
3946 val_phi->init_req(3, rbtrue);
3947 mem_phi->init_req(3, wb_mem);
3948 raw_mem_phi->init_req(3, raw_mem);
3949
3950 Node* in_cset_fast_test_failure = new IfTrueNode(in_cset_fast_test_iff);
3951 phase->register_control(in_cset_fast_test_failure, loop, in_cset_fast_test_iff);
3952
3953 c = in_cset_fast_test_failure;
3954 }
3955 }
3956
3957 void ShenandoahWriteBarrierNode::evacuation_in_progress(Node* c, Node* val, Node* evacuation_iff, Node* unc, Node* unc_ctrl,
3958 Node* raw_mem, Node* wb_mem, Node* region, Node* val_phi, Node* mem_phi,
3959 Node* raw_mem_phi, Node* unc_region, int alias, Unique_Node_List& uses,
3960 PhaseIdealLoop* phase) {
3961 evacuation_in_progress_null_check(c, val, evacuation_iff, unc, unc_ctrl, unc_region, uses, phase);
3962
3963 IdealLoopTree *loop = phase->get_loop(c);
3964 Node* rbtrue = new ShenandoahReadBarrierNode(c, wb_mem, val);
3965 phase->register_new_node(rbtrue, c);
3966
3967 Node* in_cset_fast_test_failure = NULL;
3968 in_cset_fast_test(c, rbtrue, raw_mem, wb_mem, region, val_phi, mem_phi, raw_mem_phi, phase);
3969
3970 // The slow path stub consumes and produces raw memory in addition
3971 // to the existing memory edges
3972 Node* base = find_bottom_mem(c, phase);
3973
3974 MergeMemNode* mm = MergeMemNode::make(base);
3975 mm->set_memory_at(alias, wb_mem);
3976 mm->set_memory_at(Compile::AliasIdxRaw, raw_mem);
3977 phase->register_new_node(mm, c);
3978
3979 Node* call = new CallLeafNoFPNode(ShenandoahBarrierSetC2::shenandoah_write_barrier_Type(), StubRoutines::shenandoah_wb_C(), "shenandoah_write_barrier", TypeRawPtr::BOTTOM);
3980 call->init_req(TypeFunc::Control, c);
3981 call->init_req(TypeFunc::I_O, phase->C->top());
3982 call->init_req(TypeFunc::Memory, mm);
3983 call->init_req(TypeFunc::FramePtr, phase->C->top());
3984 call->init_req(TypeFunc::ReturnAdr, phase->C->top());
3985 call->init_req(TypeFunc::Parms, rbtrue);
3986 phase->register_control(call, loop, c);
3987 Node* ctrl_proj = new ProjNode(call, TypeFunc::Control);
3988 phase->register_control(ctrl_proj, loop, call);
3989 Node* mem_proj = new ProjNode(call, TypeFunc::Memory);
3990 phase->register_new_node(mem_proj, call);
3991 Node* res_proj = new ProjNode(call, TypeFunc::Parms);
3992 phase->register_new_node(res_proj, call);
3993 Node* res = new CheckCastPPNode(ctrl_proj, res_proj, phase->igvn().type(val)->is_oopptr()->cast_to_nonconst());
3994 phase->register_new_node(res, ctrl_proj);
3995 region->init_req(2, ctrl_proj);
3996 val_phi->init_req(2, res);
3997 mem_phi->init_req(2, mem_proj);
3998 raw_mem_phi->init_req(2, mem_proj);
3999 }
4000
4001 void ShenandoahWriteBarrierNode::pin_and_expand(PhaseIdealLoop* phase) {
4002 const bool trace = false;
4003
4004 // Collect raw memory state at CFG points in the entire graph and
4005 // record it in memory_nodes. Optimize the raw memory graph in the
4006 // process. Optimizing the memory graph also makes the memory graph
4007 // simpler.
4008 Node_List memory_nodes;
4009 collect_memory_nodes(Compile::AliasIdxRaw, memory_nodes, phase);
4010
4011 // Let's try to common write barriers again
4012 for (;;) {
4013 bool progress = false;
4014 for (int i = ShenandoahBarrierSetC2::bsc2()->state()->shenandoah_barriers_count(); i > 0; i--) {
4015 ShenandoahBarrierNode* wb = ShenandoahBarrierSetC2::bsc2()->state()->shenandoah_barrier(i-1);
4016 Node* ctrl = phase->get_ctrl(wb);
4017 if (wb->try_common(ctrl, phase) != NULL) {
4018 progress = true;
4019 }
4020 }
4021 if (!progress) {
4022 break;
4023 }
4024 }
4025
4026 Unique_Node_List uses;
4027 for (int i = 0; i < ShenandoahBarrierSetC2::bsc2()->state()->shenandoah_barriers_count(); i++) {
4028 ShenandoahWriteBarrierNode* wb = ShenandoahBarrierSetC2::bsc2()->state()->shenandoah_barrier(i);
4029 Node* ctrl = phase->get_ctrl(wb);
4030
4031 Node* val = wb->in(ValueIn);
4032 if (ctrl->is_Proj() && ctrl->in(0)->is_CallJava()) {
4033 assert(is_dominator(phase->get_ctrl(val), ctrl->in(0)->in(0), val, ctrl->in(0), phase), "can't move");
4034 phase->set_ctrl(wb, ctrl->in(0)->in(0));
4035 } else if (ctrl->is_CallRuntime()) {
4036 assert(is_dominator(phase->get_ctrl(val), ctrl->in(0), val, ctrl, phase), "can't move");
4037 phase->set_ctrl(wb, ctrl->in(0));
4038 }
4039
4040 assert(wb->Opcode() == Op_ShenandoahWriteBarrier, "only for write barriers");
4041 // Look for a null check that dominates this barrier and move the
4042 // barrier right after the null check to enable implicit null
4043 // checks
4044 wb->pin_and_expand_move_barrier(phase, uses);
4045
4046 wb->pin_and_expand_helper(phase);
4047 }
4048
4049 Unique_Node_List uses_to_ignore;
4050 for (int i = ShenandoahBarrierSetC2::bsc2()->state()->shenandoah_barriers_count(); i > 0; i--) {
4051 int cnt = ShenandoahBarrierSetC2::bsc2()->state()->shenandoah_barriers_count();
4052 ShenandoahWriteBarrierNode* wb = ShenandoahBarrierSetC2::bsc2()->state()->shenandoah_barrier(i-1);
4053
4054 uint last = phase->C->unique();
4055 Node* ctrl = phase->get_ctrl(wb);
4056
4057 Node* raw_mem = find_raw_mem(ctrl, wb, memory_nodes, phase);
4058 Node* init_raw_mem = raw_mem;
4059 Node* raw_mem_for_ctrl = find_raw_mem(ctrl, NULL, memory_nodes, phase);
4060 int alias = phase->C->get_alias_index(wb->adr_type());
4061 Node* wb_mem = wb->in(Memory);
4062 Node* init_wb_mem = wb_mem;
4063
4064 Node* val = wb->in(ValueIn);
4065 Node* wbproj = wb->find_out_with(Op_ShenandoahWBMemProj);
4066 IdealLoopTree *loop = phase->get_loop(ctrl);
4067
4068 assert(val->Opcode() != Op_ShenandoahWriteBarrier || phase->C->has_irreducible_loop(), "No chain of write barriers");
4069
4070 CallStaticJavaNode* unc = wb->pin_and_expand_null_check(phase->igvn());
4071 Node* unc_ctrl = NULL;
4072 if (unc != NULL) {
4073 if (val->in(0) != ctrl) {
4074 unc = NULL;
4075 } else {
4076 unc_ctrl = val->in(0);
4077 }
4078 }
4079
4080 Node* uncasted_val = val;
4081 if (unc != NULL) {
4082 uncasted_val = val->in(1);
4083 }
4084
4085 Node* evac_in_progress = NULL;
4086 Node* evac_not_in_progress = NULL;
4087 Node* heap_stable_ctrl = NULL;
4088 test_evacuation_in_progress(ctrl, alias, raw_mem, wb_mem, evac_in_progress, evac_not_in_progress, heap_stable_ctrl, phase);
4089 IfNode* evacuation_iff = evac_in_progress->in(0)->as_If();
4090 IfNode* heap_stable_iff = heap_stable_ctrl->in(0)->as_If();
4091
4092 Node* evacuation_region = new RegionNode(4);
4093 Node* evacuation_val_phi = new PhiNode(evacuation_region, uncasted_val->bottom_type()->is_oopptr()->cast_to_nonconst());
4094 Node* evacuation_mem_phi = PhiNode::make(evacuation_region, wb_mem, Type::MEMORY, phase->C->alias_type(wb->adr_type())->adr_type());
4095 Node* evacuation_raw_mem_phi = PhiNode::make(evacuation_region, raw_mem, Type::MEMORY, TypeRawPtr::BOTTOM);
4096 Node* region = new RegionNode(3);
4097 Node* val_phi = new PhiNode(region, uncasted_val->bottom_type()->is_oopptr()->cast_to_nonconst());
4098 Node* mem_phi = PhiNode::make(region, wb_mem, Type::MEMORY, phase->C->alias_type(wb->adr_type())->adr_type());
4099 Node* raw_mem_phi = PhiNode::make(region, raw_mem, Type::MEMORY, TypeRawPtr::BOTTOM);
4100
4101 Node* unc_region = NULL;
4102 evacuation_not_in_progress(evac_not_in_progress, val, unc_ctrl, raw_mem, wb_mem,
4103 evacuation_region, evacuation_val_phi, evacuation_mem_phi, evacuation_raw_mem_phi, unc_region,
4104 phase);
4105
4106 heap_stable(heap_stable_ctrl, val, unc_ctrl, init_raw_mem, init_wb_mem, region, val_phi, mem_phi, raw_mem_phi,
4107 unc_region, phase);
4108
4109 evacuation_in_progress(evac_in_progress, val, evacuation_iff, unc, unc_ctrl,
4110 raw_mem, wb_mem, evacuation_region, evacuation_val_phi, evacuation_mem_phi, evacuation_raw_mem_phi,
4111 unc_region, alias, uses,
4112 phase);
4113 region->init_req(2, evacuation_region);
4114 val_phi->init_req(2, evacuation_val_phi);
4115 mem_phi->init_req(2, evacuation_mem_phi);
4116 raw_mem_phi->init_req(2, evacuation_raw_mem_phi);
4117 phase->register_control(evacuation_region, loop, evacuation_iff);
4118 phase->register_new_node(evacuation_val_phi, evacuation_region);
4119 phase->register_new_node(evacuation_mem_phi, evacuation_region);
4120 phase->register_new_node(evacuation_raw_mem_phi, evacuation_region);
4121
4122 phase->register_control(region, loop, heap_stable_iff);
4123
4124 Node* out_val = val_phi;
4125 phase->register_new_node(val_phi, region);
4126 phase->register_new_node(mem_phi, region);
4127 phase->register_new_node(raw_mem_phi, region);
4128
4129 // Update the control of all nodes that should be after the
4130 // barrier control flow
4131 uses.clear();
4132 // Every node that is control dependent on the barrier's input
4133 // control will be after the expanded barrier. The raw memory (if
4134 // its memory is control dependent on the barrier's input control)
4135 // must stay above the barrier.
4136 uses_to_ignore.clear();
4137 if (phase->has_ctrl(init_raw_mem) && phase->get_ctrl(init_raw_mem) == ctrl && !init_raw_mem->is_Phi()) {
4138 uses_to_ignore.push(init_raw_mem);
4139 }
4140 for (uint next = 0; next < uses_to_ignore.size(); next++) {
4141 Node *n = uses_to_ignore.at(next);
4142 for (uint i = 0; i < n->req(); i++) {
4143 Node* in = n->in(i);
4144 if (in != NULL && phase->has_ctrl(in) && phase->get_ctrl(in) == ctrl) {
4145 uses_to_ignore.push(in);
4146 }
4147 }
4148 }
4149 for (DUIterator_Fast imax, i = ctrl->fast_outs(imax); i < imax; i++) {
4150 Node* u = ctrl->fast_out(i);
4151 if (u->_idx < last &&
4152 u != wb &&
4153 !uses_to_ignore.member(u) &&
4154 (u->in(0) != ctrl || (!u->is_Region() && !u->is_Phi())) &&
4155 (ctrl->Opcode() != Op_CatchProj || u->Opcode() != Op_CreateEx)) {
4156 Node* old_c = phase->ctrl_or_self(u);
4157 Node* c = old_c;
4158 if (c != ctrl ||
4159 is_dominator_same_ctrl(old_c, wb, u, phase) ||
4160 u->is_g1_marking_load()) {
4161 phase->igvn().rehash_node_delayed(u);
4162 int nb = u->replace_edge(ctrl, region);
4163 if (u->is_CFG()) {
4164 if (phase->idom(u) == ctrl) {
4165 phase->set_idom(u, region, phase->dom_depth(region));
4166 }
4167 } else if (phase->get_ctrl(u) == ctrl) {
4168 assert(u != init_raw_mem, "should leave input raw mem above the barrier");
4169 uses.push(u);
4170 }
4171 assert(nb == 1, "more than 1 ctrl input?");
4172 --i, imax -= nb;
4173 }
4174 }
4175 }
4176
4177 if (wbproj != NULL) {
4178 phase->igvn().replace_input_of(wbproj, 0, phase->C->top());
4179 phase->lazy_replace(wbproj, mem_phi);
4180 }
4181 if (unc != NULL) {
4182 for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) {
4183 Node* u = val->fast_out(i);
4184 Node* c = phase->ctrl_or_self(u);
4185 if (u != wb && (c != ctrl || is_dominator_same_ctrl(c, wb, u, phase))) {
4186 phase->igvn().rehash_node_delayed(u);
4187 int nb = u->replace_edge(val, out_val);
4188 --i, imax -= nb;
4189 }
4190 }
4191 if (val->outcnt() == 0) {
4192 phase->lazy_update(val, out_val);
4193 phase->igvn()._worklist.push(val);
4194 }
4195 }
4196 phase->lazy_replace(wb, out_val);
4197
4198 follow_barrier_uses(mem_phi, ctrl, uses, phase);
4199 follow_barrier_uses(out_val, ctrl, uses, phase);
4200
4201 for(uint next = 0; next < uses.size(); next++ ) {
4202 Node *n = uses.at(next);
4203 assert(phase->get_ctrl(n) == ctrl, "bad control");
4204 assert(n != init_raw_mem, "should leave input raw mem above the barrier");
4205 phase->set_ctrl(n, region);
4206 follow_barrier_uses(n, ctrl, uses, phase);
4207 }
4208
4209 // The slow path call produces memory: hook the raw memory phi
4210 // from the expanded write barrier with the rest of the graph
4211 // which may require adding memory phis at every post dominated
4212 // region and at enclosing loop heads. Use the memory state
4213 // collected in memory_nodes to fix the memory graph. Update that
4214 // memory state as we go.
4215 fix_raw_mem(ctrl,region, init_raw_mem, raw_mem_for_ctrl, raw_mem_phi, memory_nodes, uses, phase);
4216 assert(ShenandoahBarrierSetC2::bsc2()->state()->shenandoah_barriers_count() == cnt - 1, "not replaced");
4217 }
4218
4219 assert(ShenandoahBarrierSetC2::bsc2()->state()->shenandoah_barriers_count() == 0, "all write barrier nodes should have been replaced");
4220 }
4221
4222 void ShenandoahWriteBarrierNode::move_evacuation_test_out_of_loop(IfNode* iff, PhaseIdealLoop* phase) {
4223 // move test and its mem barriers out of the loop
4224 assert(is_evacuation_in_progress_test(iff), "inconsistent");
4225
4226 IdealLoopTree *loop = phase->get_loop(iff);
4227 Node* loop_head = loop->_head;
4228 Node* entry_c = loop_head->in(LoopNode::EntryControl);
4229
4230 Node* load = iff->in(1)->in(1)->in(1)->in(1);
4231 assert(is_gc_state_load(load), "broken");
4232 if (!phase->is_dominator(load->in(0), entry_c)) {
4233 Node* mem_ctrl = NULL;
4234 Node* mem = dom_mem(load->in(MemNode::Memory), loop_head, Compile::AliasIdxRaw, mem_ctrl, phase);
4235 phase->igvn().replace_input_of(load, MemNode::Memory, mem);
4236 phase->igvn().replace_input_of(load, 0, entry_c);
4237 phase->set_ctrl_and_loop(load, entry_c);
4238 }
4239 }
4240
4241 void ShenandoahWriteBarrierNode::move_heap_stable_test_out_of_loop(IfNode* iff, PhaseIdealLoop* phase) {
4242 IdealLoopTree *loop = phase->get_loop(iff);
4243 Node* loop_head = loop->_head;
4244 Node* entry_c = loop_head->in(LoopNode::EntryControl);
4245
4246 Node* load = iff->in(1)->in(1)->in(1);
4247 assert(is_gc_state_load(load), "broken");
4248 if (!phase->is_dominator(load->in(0), entry_c)) {
4249 Node* mem_ctrl = NULL;
4250 Node* mem = dom_mem(load->in(MemNode::Memory), loop_head, Compile::AliasIdxRaw, mem_ctrl, phase);
4251 phase->igvn().replace_input_of(load, MemNode::Memory, mem);
4252 phase->igvn().replace_input_of(load, 0, entry_c);
4253 phase->set_ctrl_and_loop(load, entry_c);
4254 }
4255 }
4256
4257 void ShenandoahWriteBarrierNode::merge_back_to_back_tests(Node* n, PhaseIdealLoop* phase) {
4258 assert(is_evacuation_in_progress_test(n) || is_heap_stable_test(n), "no other tests");
4259 if (phase->identical_backtoback_ifs(n)) {
4260 Node* n_ctrl = is_evacuation_in_progress_test(n) ? ShenandoahWriteBarrierNode::evacuation_in_progress_test_ctrl(n) : n->in(0);
4261 if (phase->can_split_if(n_ctrl)) {
4262 IfNode* dom_if = phase->idom(n_ctrl)->as_If();
4263 if (is_heap_stable_test(n)) {
4264 Node* gc_state_load = n->in(1)->in(1)->in(1);
4265 assert(is_gc_state_load(gc_state_load), "broken");
4266 Node* dom_gc_state_load = dom_if->in(1)->in(1)->in(1);
4267 assert(is_gc_state_load(dom_gc_state_load), "broken");
4268 if (gc_state_load != dom_gc_state_load) {
4269 phase->igvn().replace_node(gc_state_load, dom_gc_state_load);
4270 }
4271 }
4272 PhiNode* bolphi = PhiNode::make_blank(n_ctrl, n->in(1));
4273 Node* proj_true = dom_if->proj_out(1);
4274 Node* proj_false = dom_if->proj_out(0);
4275 Node* con_true = phase->igvn().makecon(TypeInt::ONE);
4276 Node* con_false = phase->igvn().makecon(TypeInt::ZERO);
4277
4278 for (uint i = 1; i < n_ctrl->req(); i++) {
4279 if (phase->is_dominator(proj_true, n_ctrl->in(i))) {
4280 bolphi->init_req(i, con_true);
4281 } else {
4282 assert(phase->is_dominator(proj_false, n_ctrl->in(i)), "bad if");
4283 bolphi->init_req(i, con_false);
4284 }
4285 }
4286 phase->register_new_node(bolphi, n_ctrl);
4287 phase->igvn().replace_input_of(n, 1, bolphi);
4288 phase->do_split_if(n);
4289 }
4290 }
4291 }
4292
4293 void ShenandoahWriteBarrierNode::optimize_after_expansion(VectorSet &visited, Node_Stack &stack, Node_List &old_new, PhaseIdealLoop* phase) {
4294 Node_List heap_stable_tests;
4295 Node_List evacuation_tests;
4296 Node_List gc_state_loads;
4297
4298 stack.push(phase->C->start(), 0);
4299 do {
4300 Node* n = stack.node();
4301 uint i = stack.index();
4302
4303 if (i < n->outcnt()) {
4304 Node* u = n->raw_out(i);
4305 stack.set_index(i+1);
4306 if (!visited.test_set(u->_idx)) {
4307 stack.push(u, 0);
4308 }
4309 } else {
4310 stack.pop();
4311 if (n->is_If() && ShenandoahWriteBarrierNode::is_evacuation_in_progress_test(n)) {
4312 evacuation_tests.push(n);
4313 }
4314 if (ShenandoahCommonGCStateLoads && ShenandoahWriteBarrierNode::is_gc_state_load(n)) {
4315 gc_state_loads.push(n);
4316 }
4317 if (n->is_If() && ShenandoahWriteBarrierNode::is_heap_stable_test(n)) {
4318 heap_stable_tests.push(n);
4319 }
4320 }
4321 } while (stack.size() > 0);
4322
4323 bool progress;
4324 do {
4325 progress = false;
4326 for (uint i = 0; i < gc_state_loads.size(); i++) {
4327 Node* n = gc_state_loads.at(i);
4328 if (n->outcnt() != 0) {
4329 progress |= ShenandoahWriteBarrierNode::try_common_gc_state_load(n, phase);
4330 }
4331 }
4332 } while (progress);
4333
4334 for (uint i = 0; i < heap_stable_tests.size(); i++) {
4335 Node* n = heap_stable_tests.at(i);
4336 assert(is_heap_stable_test(n), "only evacuation test");
4337 merge_back_to_back_tests(n, phase);
4338 }
4339
4340 if (!phase->C->major_progress()) {
4341 for (uint i = 0; i < evacuation_tests.size(); i++) {
4342 Node* n = evacuation_tests.at(i);
4343 assert(is_evacuation_in_progress_test(n), "only evacuation test");
4344 merge_back_to_back_tests(n, phase);
4345 }
4346 }
4347
4348 if (!phase->C->major_progress()) {
4349 VectorSet seen(Thread::current()->resource_area());
4350 for (uint i = 0; i < heap_stable_tests.size(); i++) {
4351 Node* n = heap_stable_tests.at(i);
4352 IdealLoopTree* loop = phase->get_loop(n);
4353 if (loop != phase->ltree_root() &&
4354 loop->_child == NULL &&
4355 !loop->_irreducible) {
4356 LoopNode* head = loop->_head->as_Loop();
4357 if ((!head->is_CountedLoop() || head->as_CountedLoop()->is_main_loop() || head->as_CountedLoop()->is_normal_loop()) &&
4358 !seen.test_set(head->_idx) &&
4359 loop->policy_unswitching(phase, true)) {
4360 IfNode* iff = phase->find_unswitching_candidate(loop, true);
4361 if (iff != NULL && (is_evacuation_in_progress_test(iff) || is_heap_stable_test(iff))) {
4362 if (head->is_strip_mined()) {
4363 head->verify_strip_mined(0);
4364 OuterStripMinedLoopNode* outer = head->as_CountedLoop()->outer_loop();
4365 OuterStripMinedLoopEndNode* le = head->outer_loop_end();
4366 Node* new_outer = new LoopNode(outer->in(LoopNode::EntryControl), outer->in(LoopNode::LoopBackControl));
4367 phase->register_control(new_outer, phase->get_loop(outer), outer->in(LoopNode::EntryControl));
4368 Node* new_le = new IfNode(le->in(0), le->in(1), le->_prob, le->_fcnt);
4369 phase->register_control(new_le, phase->get_loop(le), le->in(0));
4370 phase->lazy_replace(outer, new_outer);
4371 phase->lazy_replace(le, new_le);
4372 head->clear_strip_mined();
4373 }
4374 phase->do_unswitching(loop, old_new, true);
4375 }
4376 }
4377 }
4378 }
4379 }
4380 }
4381
4382 #ifdef ASSERT
4383 void ShenandoahBarrierNode::verify_raw_mem(RootNode* root) {
4384 const bool trace = false;
4385 ResourceMark rm;
4386 Unique_Node_List nodes;
4387 Unique_Node_List controls;
4388 Unique_Node_List memories;
4389
4390 nodes.push(root);
4391 for (uint next = 0; next < nodes.size(); next++) {
4392 Node *n = nodes.at(next);
4393 if (n->Opcode() == Op_CallLeafNoFP && n->as_Call()->_entry_point == StubRoutines::shenandoah_wb_C()) {
4394 controls.push(n);
4395 if (trace) { tty->print("XXXXXX verifying"); n->dump(); }
4396 for (uint next2 = 0; next2 < controls.size(); next2++) {
4397 Node *m = controls.at(next2);
4398 if (!m->is_Loop() || controls.member(m->in(LoopNode::EntryControl)) || 1) {
4399 for (DUIterator_Fast imax, i = m->fast_outs(imax); i < imax; i++) {
4400 Node* u = m->fast_out(i);
4401 if (u->is_CFG() && !u->is_Root() &&
4402 !(u->Opcode() == Op_CProj && u->in(0)->Opcode() == Op_NeverBranch && u->as_Proj()->_con == 1) &&
4403 !(u->is_Region() && u->unique_ctrl_out()->Opcode() == Op_Halt)) {
4404 if (trace) { tty->print("XXXXXX pushing control"); u->dump(); }
4405 controls.push(u);
4406 }
4407 }
4408 }
4409 }
4410 memories.push(n->as_Call()->proj_out(TypeFunc::Memory));
4411 for (uint next2 = 0; next2 < memories.size(); next2++) {
4412 Node *m = memories.at(next2);
4413 assert(m->bottom_type() == Type::MEMORY, "");
4414 if (!m->is_Phi() || !m->in(0)->is_Loop() || controls.member(m->in(0)->in(LoopNode::EntryControl)) || 1) {
4415 for (DUIterator_Fast imax, i = m->fast_outs(imax); i < imax; i++) {
4416 Node* u = m->fast_out(i);
4417 if (u->bottom_type() == Type::MEMORY && (u->is_Mem() || u->is_ClearArray())) {
4418 if (trace) { tty->print("XXXXXX pushing memory"); u->dump(); }
4419 memories.push(u);
4420 } else if (u->is_LoadStore()) {
4421 if (trace) { tty->print("XXXXXX pushing memory"); u->find_out_with(Op_SCMemProj)->dump(); }
4422 memories.push(u->find_out_with(Op_SCMemProj));
4423 } else if (u->is_MergeMem() && u->as_MergeMem()->memory_at(Compile::AliasIdxRaw) == m) {
4424 if (trace) { tty->print("XXXXXX pushing memory"); u->dump(); }
4425 memories.push(u);
4426 } else if (u->is_Phi()) {
4427 assert(u->bottom_type() == Type::MEMORY, "");
4428 if (u->adr_type() == TypeRawPtr::BOTTOM || u->adr_type() == TypePtr::BOTTOM) {
4429 assert(controls.member(u->in(0)), "");
4430 if (trace) { tty->print("XXXXXX pushing memory"); u->dump(); }
4431 memories.push(u);
4432 }
4433 } else if (u->is_SafePoint() || u->is_MemBar()) {
4434 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
4435 Node* uu = u->fast_out(j);
4436 if (uu->bottom_type() == Type::MEMORY) {
4437 if (trace) { tty->print("XXXXXX pushing memory"); uu->dump(); }
4438 memories.push(uu);
4439 }
4440 }
4441 }
4442 }
4443 }
4444 }
4445 for (uint next2 = 0; next2 < controls.size(); next2++) {
4446 Node *m = controls.at(next2);
4447 if (m->is_Region()) {
4448 bool all_in = true;
4449 for (uint i = 1; i < m->req(); i++) {
4450 if (!controls.member(m->in(i))) {
4451 all_in = false;
4452 break;
4453 }
4454 }
4455 if (trace) { tty->print("XXX verifying %s", all_in ? "all in" : ""); m->dump(); }
4456 bool found_phi = false;
4457 for (DUIterator_Fast jmax, j = m->fast_outs(jmax); j < jmax && !found_phi; j++) {
4458 Node* u = m->fast_out(j);
4459 if (u->is_Phi() && memories.member(u)) {
4460 found_phi = true;
4461 for (uint i = 1; i < u->req() && found_phi; i++) {
4462 Node* k = u->in(i);
4463 if (memories.member(k) != controls.member(m->in(i))) {
4464 found_phi = false;
4465 }
4466 }
4467 }
4468 }
4469 assert(found_phi || all_in, "");
4470 }
4471 }
4472 controls.clear();
4473 memories.clear();
4474 }
4475 for( uint i = 0; i < n->len(); ++i ) {
4476 Node *m = n->in(i);
4477 if (m != NULL) {
4478 nodes.push(m);
4479 }
4480 }
4481 }
4482 }
4483 #endif
4484
4485 static bool is_on_null_check_path(Block* b, Block* null_check_block) {
4486 if (null_check_block == NULL) {
4487 return false;
4488 }
4489 do {
4490 assert(null_check_block->_num_succs == 1, "only one succ on the path to unc");
4491 if (b == null_check_block) {
4492 return true;
4493 }
4494 null_check_block = null_check_block->_succs[0];
4495 } while(!null_check_block->head()->is_Root());
4496
4497 return false;
4498 }
4499
4500 int PhaseCFG::replace_uses_with_shenandoah_barrier_helper(Node* n, Node* use, Node* val, Block* block, Block* null_check_block) {
4501 int nb = 0;
4502 Block* buse = get_block_for_node(use);
4503 if (is_on_null_check_path(buse, null_check_block)) {
4504 return 0;
4505 }
4506 if (use->is_Phi()) {
4507 for (uint j = 1; j < use->req(); j++) {
4508 if (use->in(j) == val) {
4509 Block* b = get_block_for_node(use->in(0)->in(j));
4510 if ((block != b && block->dom_lca(b) == block) ||
4511 block == b) {
4512 use->set_req(j, n);
4513 nb++;
4514 }
4515 }
4516 }
4517 } else {
4518 if ((block != buse && block->dom_lca(buse) == block) ||
4519 (block == buse && !use->is_scheduled())) {
4520 // Let precedence edges alone (can confuse anti-dependence verification code)
4521 for (uint i = 0; i < use->req(); i++) {
4522 if (use->in(i) == val) {
4523 use->set_req(i, n);
4524 nb++;
4525 }
4526 }
4527 assert(nb > 0 || use->find_prec_edge(val) != -1, "no replacement?");
4528 }
4529 }
4530
4531 return nb;
4532 }
4533
4534 void PhaseCFG::replace_uses_with_shenandoah_barrier(Node* n, Block* block, Node_List& worklist, GrowableArray<int>& ready_cnt, uint max_idx, uint& phi_cnt) {
4535 // Replace all uses of barrier's input that are dominated by the
4536 // barrier with the value returned by the barrier: no need to keep
4537 // both live.
4538 if (n->is_Mach() && n->as_Mach()->ideal_Opcode() == Op_ShenandoahReadBarrier) {
4539 MachNullCheckNode* null_check = NULL;
4540 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax && null_check == NULL; i++) {
4541 Node* use = n->fast_out(i);
4542 if (use->is_MachNullCheck()) {
4543 null_check = use->as_MachNullCheck();
4544 }
4545 }
4546 Block* null_check_block = NULL;
4547 if (null_check != NULL) {
4548 Node* proj = null_check->find_out_with(Op_IfTrue);
4549 Node* head = proj->unique_out();
4550 null_check_block = get_block_for_node(head);
4551 }
4552
4553 Node* val = n->in(ShenandoahBarrierNode::ValueIn);
4554 if (!val->bottom_type()->isa_narrowoop()) {
4555 for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) {
4556 Node* use = val->fast_out(i);
4557 if (use != n) {
4558 int nb = replace_uses_with_shenandoah_barrier_helper(n, use, val, block, null_check_block);
4559 if (nb > 0) {
4560 --i; imax -= nb;
4561 }
4562 }
4563 }
4564 } else {
4565 for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) {
4566 Node* u = val->fast_out(i);
4567 if (u->is_Mach() && u->as_Mach()->ideal_Opcode() == Op_DecodeN) {
4568 int projs = 0;
4569 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
4570 Node* uu = u->fast_out(j);
4571 assert(!uu->is_MachTemp(), "");
4572 if (uu->is_MachProj() && uu->outcnt() == 0) {
4573 projs++;
4574 } else {
4575 int nb = replace_uses_with_shenandoah_barrier_helper(n, uu, u, block, null_check_block);
4576 if (nb > 0) {
4577 if (!u->is_scheduled()) {
4578 push_ready_nodes(n, uu, block, ready_cnt, worklist, max_idx, nb);
4579 }
4580 --j; jmax -= nb;
4581 }
4582 }
4583 }
4584 // The DecodeN may have gone dead
4585 if (u->outcnt() - projs == 0) {
4586 u->disconnect_inputs(NULL, C);
4587 Block* bu = get_block_for_node(u);
4588 unmap_node_from_block(u);
4589 if (bu == block) {
4590 if (u->is_scheduled()) {
4591 block->find_remove(u);
4592 phi_cnt--;
4593 } else {
4594 worklist.yank(u);
4595 block->remove_node(block->end_idx()-1);
4596 }
4597 } else {
4598 bu->find_remove(u);
4599 }
4600 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
4601 Node* uu = u->fast_out(j);
4602 assert(uu->is_MachProj() && uu->outcnt() == 0, "");
4603 assert(bu == get_block_for_node(uu), "");
4604 uu->disconnect_inputs(NULL, C);
4605 --j; --jmax;
4606 unmap_node_from_block(uu);
4607 if (bu == block) {
4608 if (u->is_scheduled()) {
4609 block->find_remove(uu);
4610 phi_cnt--;
4611 } else {
4612 worklist.yank(uu);
4613 block->remove_node(block->end_idx()-1);
4614 }
4615 } else {
4616 bu->find_remove(uu);
4617 }
4618 assert(uu->is_scheduled() == u->is_scheduled(), "");
4619 }
4620 --i; --imax;
4621 }
4622 }
4623 }
4624 }
4625 }
4626 }