// Copyright 2015 the V8 project authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #include "src/compiler/access-builder.h" #include "src/compiler/common-operator.h" #include "src/compiler/graph.h" #include "src/compiler/graph-visualizer.h" #include "src/compiler/js-operator.h" #include "src/compiler/node.h" #include "src/compiler/opcodes.h" #include "src/compiler/operator.h" #include "src/compiler/schedule.h" #include "src/compiler/scheduler.h" #include "src/compiler/simplified-operator.h" #include "src/compiler/source-position.h" #include "src/compiler/verifier.h" #include "test/unittests/compiler/compiler-test-utils.h" #include "test/unittests/test-utils.h" #include "testing/gmock/include/gmock/gmock.h" using testing::AnyOf; namespace v8 { namespace internal { namespace compiler { class SchedulerTest : public TestWithIsolateAndZone { public: SchedulerTest() : graph_(zone()), common_(zone()), simplified_(zone()), js_(zone()) {} Schedule* ComputeAndVerifySchedule(size_t expected) { if (FLAG_trace_turbo) { OFStream os(stdout); SourcePositionTable table(graph()); os << AsJSON(*graph(), &table); } Schedule* schedule = Scheduler::ComputeSchedule(zone(), graph(), Scheduler::kSplitNodes); if (FLAG_trace_turbo_scheduler) { OFStream os(stdout); os << *schedule << std::endl; } ScheduleVerifier::Run(schedule); EXPECT_EQ(expected, GetScheduledNodeCount(schedule)); return schedule; } size_t GetScheduledNodeCount(const Schedule* schedule) { size_t node_count = 0; for (auto block : *schedule->rpo_order()) { node_count += block->NodeCount(); if (block->control() != BasicBlock::kNone) ++node_count; } return node_count; } Graph* graph() { return &graph_; } CommonOperatorBuilder* common() { return &common_; } SimplifiedOperatorBuilder* simplified() { return &simplified_; } JSOperatorBuilder* js() { return &js_; } private: Graph graph_; CommonOperatorBuilder common_; SimplifiedOperatorBuilder simplified_; JSOperatorBuilder js_; }; namespace { const Operator kHeapConstant(IrOpcode::kHeapConstant, Operator::kPure, "HeapConstant", 0, 0, 0, 1, 0, 0); const Operator kIntAdd(IrOpcode::kInt32Add, Operator::kPure, "Int32Add", 2, 0, 0, 1, 0, 0); const Operator kMockCall(IrOpcode::kCall, Operator::kNoProperties, "MockCall", 0, 0, 1, 1, 1, 2); const Operator kMockTailCall(IrOpcode::kTailCall, Operator::kNoProperties, "MockTailCall", 1, 1, 1, 0, 0, 1); } // namespace TEST_F(SchedulerTest, BuildScheduleEmpty) { graph()->SetStart(graph()->NewNode(common()->Start(0))); graph()->SetEnd(graph()->NewNode(common()->End(1), graph()->start())); USE(Scheduler::ComputeSchedule(zone(), graph(), Scheduler::kNoFlags)); } TEST_F(SchedulerTest, BuildScheduleOneParameter) { graph()->SetStart(graph()->NewNode(common()->Start(0))); Node* p1 = graph()->NewNode(common()->Parameter(0), graph()->start()); Node* ret = graph()->NewNode(common()->Return(), p1, graph()->start(), graph()->start()); graph()->SetEnd(graph()->NewNode(common()->End(1), ret)); USE(Scheduler::ComputeSchedule(zone(), graph(), Scheduler::kNoFlags)); } namespace { Node* CreateDiamond(Graph* graph, CommonOperatorBuilder* common, Node* cond) { Node* tv = graph->NewNode(common->Int32Constant(6)); Node* fv = graph->NewNode(common->Int32Constant(7)); Node* br = graph->NewNode(common->Branch(), cond, graph->start()); Node* t = graph->NewNode(common->IfTrue(), br); Node* f = graph->NewNode(common->IfFalse(), br); Node* m = graph->NewNode(common->Merge(2), t, f); Node* phi = graph->NewNode(common->Phi(MachineRepresentation::kTagged, 2), tv, fv, m); return phi; } } // namespace TARGET_TEST_F(SchedulerTest, FloatingDiamond1) { Node* start = graph()->NewNode(common()->Start(1)); graph()->SetStart(start); Node* p0 = graph()->NewNode(common()->Parameter(0), start); Node* d1 = CreateDiamond(graph(), common(), p0); Node* ret = graph()->NewNode(common()->Return(), d1, start, start); Node* end = graph()->NewNode(common()->End(1), ret); graph()->SetEnd(end); ComputeAndVerifySchedule(13); } TARGET_TEST_F(SchedulerTest, FloatingDiamond2) { Node* start = graph()->NewNode(common()->Start(2)); graph()->SetStart(start); Node* p0 = graph()->NewNode(common()->Parameter(0), start); Node* p1 = graph()->NewNode(common()->Parameter(1), start); Node* d1 = CreateDiamond(graph(), common(), p0); Node* d2 = CreateDiamond(graph(), common(), p1); Node* add = graph()->NewNode(&kIntAdd, d1, d2); Node* ret = graph()->NewNode(common()->Return(), add, start, start); Node* end = graph()->NewNode(common()->End(1), ret); graph()->SetEnd(end); ComputeAndVerifySchedule(24); } TARGET_TEST_F(SchedulerTest, FloatingDiamond3) { Node* start = graph()->NewNode(common()->Start(2)); graph()->SetStart(start); Node* p0 = graph()->NewNode(common()->Parameter(0), start); Node* p1 = graph()->NewNode(common()->Parameter(1), start); Node* d1 = CreateDiamond(graph(), common(), p0); Node* d2 = CreateDiamond(graph(), common(), p1); Node* add = graph()->NewNode(&kIntAdd, d1, d2); Node* d3 = CreateDiamond(graph(), common(), add); Node* ret = graph()->NewNode(common()->Return(), d3, start, start); Node* end = graph()->NewNode(common()->End(1), ret); graph()->SetEnd(end); ComputeAndVerifySchedule(33); } TARGET_TEST_F(SchedulerTest, NestedFloatingDiamonds) { Node* start = graph()->NewNode(common()->Start(2)); graph()->SetStart(start); Node* p0 = graph()->NewNode(common()->Parameter(0), start); Node* fv = graph()->NewNode(common()->Int32Constant(7)); Node* br = graph()->NewNode(common()->Branch(), p0, graph()->start()); Node* t = graph()->NewNode(common()->IfTrue(), br); Node* f = graph()->NewNode(common()->IfFalse(), br); Node* map = graph()->NewNode( simplified()->LoadElement(AccessBuilder::ForFixedArrayElement()), p0, p0, start, f); Node* br1 = graph()->NewNode(common()->Branch(), map, graph()->start()); Node* t1 = graph()->NewNode(common()->IfTrue(), br1); Node* f1 = graph()->NewNode(common()->IfFalse(), br1); Node* m1 = graph()->NewNode(common()->Merge(2), t1, f1); Node* ttrue = graph()->NewNode(common()->Int32Constant(1)); Node* ffalse = graph()->NewNode(common()->Int32Constant(0)); Node* phi1 = graph()->NewNode( common()->Phi(MachineRepresentation::kTagged, 2), ttrue, ffalse, m1); Node* m = graph()->NewNode(common()->Merge(2), t, f); Node* phi = graph()->NewNode(common()->Phi(MachineRepresentation::kTagged, 2), fv, phi1, m); Node* ephi1 = graph()->NewNode(common()->EffectPhi(2), start, map, m); Node* ret = graph()->NewNode(common()->Return(), phi, ephi1, start); Node* end = graph()->NewNode(common()->End(1), ret); graph()->SetEnd(end); ComputeAndVerifySchedule(23); } TARGET_TEST_F(SchedulerTest, NestedFloatingDiamondWithChain) { Node* start = graph()->NewNode(common()->Start(2)); graph()->SetStart(start); Node* p0 = graph()->NewNode(common()->Parameter(0), start); Node* p1 = graph()->NewNode(common()->Parameter(1), start); Node* c = graph()->NewNode(common()->Int32Constant(7)); Node* brA1 = graph()->NewNode(common()->Branch(), p0, graph()->start()); Node* tA1 = graph()->NewNode(common()->IfTrue(), brA1); Node* fA1 = graph()->NewNode(common()->IfFalse(), brA1); Node* mA1 = graph()->NewNode(common()->Merge(2), tA1, fA1); Node* phiA1 = graph()->NewNode( common()->Phi(MachineRepresentation::kTagged, 2), p0, p1, mA1); Node* brB1 = graph()->NewNode(common()->Branch(), p1, graph()->start()); Node* tB1 = graph()->NewNode(common()->IfTrue(), brB1); Node* fB1 = graph()->NewNode(common()->IfFalse(), brB1); Node* mB1 = graph()->NewNode(common()->Merge(2), tB1, fB1); Node* phiB1 = graph()->NewNode( common()->Phi(MachineRepresentation::kTagged, 2), p0, p1, mB1); Node* brA2 = graph()->NewNode(common()->Branch(), phiB1, mA1); Node* tA2 = graph()->NewNode(common()->IfTrue(), brA2); Node* fA2 = graph()->NewNode(common()->IfFalse(), brA2); Node* mA2 = graph()->NewNode(common()->Merge(2), tA2, fA2); Node* phiA2 = graph()->NewNode( common()->Phi(MachineRepresentation::kTagged, 2), phiB1, c, mA2); Node* brB2 = graph()->NewNode(common()->Branch(), phiA1, mB1); Node* tB2 = graph()->NewNode(common()->IfTrue(), brB2); Node* fB2 = graph()->NewNode(common()->IfFalse(), brB2); Node* mB2 = graph()->NewNode(common()->Merge(2), tB2, fB2); Node* phiB2 = graph()->NewNode( common()->Phi(MachineRepresentation::kTagged, 2), phiA1, c, mB2); Node* add = graph()->NewNode(&kIntAdd, phiA2, phiB2); Node* ret = graph()->NewNode(common()->Return(), add, start, start); Node* end = graph()->NewNode(common()->End(1), ret); graph()->SetEnd(end); ComputeAndVerifySchedule(36); } TARGET_TEST_F(SchedulerTest, NestedFloatingDiamondWithLoop) { Node* start = graph()->NewNode(common()->Start(2)); graph()->SetStart(start); Node* p0 = graph()->NewNode(common()->Parameter(0), start); Node* fv = graph()->NewNode(common()->Int32Constant(7)); Node* br = graph()->NewNode(common()->Branch(), p0, graph()->start()); Node* t = graph()->NewNode(common()->IfTrue(), br); Node* f = graph()->NewNode(common()->IfFalse(), br); Node* loop = graph()->NewNode(common()->Loop(2), f, start); Node* ind = graph()->NewNode(common()->Phi(MachineRepresentation::kTagged, 2), p0, p0, loop); Node* add = graph()->NewNode(&kIntAdd, ind, fv); Node* br1 = graph()->NewNode(common()->Branch(), add, loop); Node* t1 = graph()->NewNode(common()->IfTrue(), br1); Node* f1 = graph()->NewNode(common()->IfFalse(), br1); loop->ReplaceInput(1, t1); // close loop. ind->ReplaceInput(1, ind); // close induction variable. Node* m = graph()->NewNode(common()->Merge(2), t, f1); Node* phi = graph()->NewNode(common()->Phi(MachineRepresentation::kTagged, 2), fv, ind, m); Node* ret = graph()->NewNode(common()->Return(), phi, start, start); Node* end = graph()->NewNode(common()->End(1), ret); graph()->SetEnd(end); ComputeAndVerifySchedule(20); } TARGET_TEST_F(SchedulerTest, LoopedFloatingDiamond1) { Node* start = graph()->NewNode(common()->Start(2)); graph()->SetStart(start); Node* p0 = graph()->NewNode(common()->Parameter(0), start); Node* c = graph()->NewNode(common()->Int32Constant(7)); Node* loop = graph()->NewNode(common()->Loop(2), start, start); Node* ind = graph()->NewNode(common()->Phi(MachineRepresentation::kTagged, 2), p0, p0, loop); Node* add = graph()->NewNode(&kIntAdd, ind, c); Node* br = graph()->NewNode(common()->Branch(), add, loop); Node* t = graph()->NewNode(common()->IfTrue(), br); Node* f = graph()->NewNode(common()->IfFalse(), br); Node* br1 = graph()->NewNode(common()->Branch(), p0, graph()->start()); Node* t1 = graph()->NewNode(common()->IfTrue(), br1); Node* f1 = graph()->NewNode(common()->IfFalse(), br1); Node* m1 = graph()->NewNode(common()->Merge(2), t1, f1); Node* phi1 = graph()->NewNode( common()->Phi(MachineRepresentation::kTagged, 2), add, p0, m1); loop->ReplaceInput(1, t); // close loop. ind->ReplaceInput(1, phi1); // close induction variable. Node* ret = graph()->NewNode(common()->Return(), ind, start, f); Node* end = graph()->NewNode(common()->End(2), ret, f); graph()->SetEnd(end); ComputeAndVerifySchedule(20); } TARGET_TEST_F(SchedulerTest, LoopedFloatingDiamond2) { Node* start = graph()->NewNode(common()->Start(2)); graph()->SetStart(start); Node* p0 = graph()->NewNode(common()->Parameter(0), start); Node* c = graph()->NewNode(common()->Int32Constant(7)); Node* loop = graph()->NewNode(common()->Loop(2), start, start); Node* ind = graph()->NewNode(common()->Phi(MachineRepresentation::kTagged, 2), p0, p0, loop); Node* br1 = graph()->NewNode(common()->Branch(), p0, graph()->start()); Node* t1 = graph()->NewNode(common()->IfTrue(), br1); Node* f1 = graph()->NewNode(common()->IfFalse(), br1); Node* m1 = graph()->NewNode(common()->Merge(2), t1, f1); Node* phi1 = graph()->NewNode( common()->Phi(MachineRepresentation::kTagged, 2), c, ind, m1); Node* add = graph()->NewNode(&kIntAdd, ind, phi1); Node* br = graph()->NewNode(common()->Branch(), add, loop); Node* t = graph()->NewNode(common()->IfTrue(), br); Node* f = graph()->NewNode(common()->IfFalse(), br); loop->ReplaceInput(1, t); // close loop. ind->ReplaceInput(1, add); // close induction variable. Node* ret = graph()->NewNode(common()->Return(), ind, start, f); Node* end = graph()->NewNode(common()->End(2), ret, f); graph()->SetEnd(end); ComputeAndVerifySchedule(20); } TARGET_TEST_F(SchedulerTest, LoopedFloatingDiamond3) { Node* start = graph()->NewNode(common()->Start(2)); graph()->SetStart(start); Node* p0 = graph()->NewNode(common()->Parameter(0), start); Node* c = graph()->NewNode(common()->Int32Constant(7)); Node* loop = graph()->NewNode(common()->Loop(2), start, start); Node* ind = graph()->NewNode(common()->Phi(MachineRepresentation::kTagged, 2), p0, p0, loop); Node* br1 = graph()->NewNode(common()->Branch(), p0, graph()->start()); Node* t1 = graph()->NewNode(common()->IfTrue(), br1); Node* f1 = graph()->NewNode(common()->IfFalse(), br1); Node* loop1 = graph()->NewNode(common()->Loop(2), t1, start); Node* ind1 = graph()->NewNode( common()->Phi(MachineRepresentation::kTagged, 2), p0, p0, loop); Node* add1 = graph()->NewNode(&kIntAdd, ind1, c); Node* br2 = graph()->NewNode(common()->Branch(), add1, loop1); Node* t2 = graph()->NewNode(common()->IfTrue(), br2); Node* f2 = graph()->NewNode(common()->IfFalse(), br2); loop1->ReplaceInput(1, t2); // close inner loop. ind1->ReplaceInput(1, ind1); // close inner induction variable. Node* m1 = graph()->NewNode(common()->Merge(2), f1, f2); Node* phi1 = graph()->NewNode( common()->Phi(MachineRepresentation::kTagged, 2), c, ind1, m1); Node* add = graph()->NewNode(&kIntAdd, ind, phi1); Node* br = graph()->NewNode(common()->Branch(), add, loop); Node* t = graph()->NewNode(common()->IfTrue(), br); Node* f = graph()->NewNode(common()->IfFalse(), br); loop->ReplaceInput(1, t); // close loop. ind->ReplaceInput(1, add); // close induction variable. Node* ret = graph()->NewNode(common()->Return(), ind, start, f); Node* end = graph()->NewNode(common()->End(2), ret, f); graph()->SetEnd(end); ComputeAndVerifySchedule(28); } TARGET_TEST_F(SchedulerTest, PhisPushedDownToDifferentBranches) { Node* start = graph()->NewNode(common()->Start(2)); graph()->SetStart(start); Node* p0 = graph()->NewNode(common()->Parameter(0), start); Node* p1 = graph()->NewNode(common()->Parameter(1), start); Node* v1 = graph()->NewNode(common()->Int32Constant(1)); Node* v2 = graph()->NewNode(common()->Int32Constant(2)); Node* v3 = graph()->NewNode(common()->Int32Constant(3)); Node* v4 = graph()->NewNode(common()->Int32Constant(4)); Node* br = graph()->NewNode(common()->Branch(), p0, graph()->start()); Node* t = graph()->NewNode(common()->IfTrue(), br); Node* f = graph()->NewNode(common()->IfFalse(), br); Node* m = graph()->NewNode(common()->Merge(2), t, f); Node* phi = graph()->NewNode(common()->Phi(MachineRepresentation::kTagged, 2), v1, v2, m); Node* phi2 = graph()->NewNode( common()->Phi(MachineRepresentation::kTagged, 2), v3, v4, m); Node* br2 = graph()->NewNode(common()->Branch(), p1, graph()->start()); Node* t2 = graph()->NewNode(common()->IfTrue(), br2); Node* f2 = graph()->NewNode(common()->IfFalse(), br2); Node* m2 = graph()->NewNode(common()->Merge(2), t2, f2); Node* phi3 = graph()->NewNode( common()->Phi(MachineRepresentation::kTagged, 2), phi, phi2, m2); Node* ret = graph()->NewNode(common()->Return(), phi3, start, start); Node* end = graph()->NewNode(common()->End(1), ret); graph()->SetEnd(end); ComputeAndVerifySchedule(24); } TARGET_TEST_F(SchedulerTest, BranchHintTrue) { Node* start = graph()->NewNode(common()->Start(1)); graph()->SetStart(start); Node* p0 = graph()->NewNode(common()->Parameter(0), start); Node* tv = graph()->NewNode(common()->Int32Constant(6)); Node* fv = graph()->NewNode(common()->Int32Constant(7)); Node* br = graph()->NewNode(common()->Branch(BranchHint::kTrue), p0, start); Node* t = graph()->NewNode(common()->IfTrue(), br); Node* f = graph()->NewNode(common()->IfFalse(), br); Node* m = graph()->NewNode(common()->Merge(2), t, f); Node* phi = graph()->NewNode(common()->Phi(MachineRepresentation::kTagged, 2), tv, fv, m); Node* ret = graph()->NewNode(common()->Return(), phi, start, start); Node* end = graph()->NewNode(common()->End(1), ret); graph()->SetEnd(end); Schedule* schedule = ComputeAndVerifySchedule(13); // Make sure the false block is marked as deferred. EXPECT_FALSE(schedule->block(t)->deferred()); EXPECT_TRUE(schedule->block(f)->deferred()); } TARGET_TEST_F(SchedulerTest, BranchHintFalse) { Node* start = graph()->NewNode(common()->Start(1)); graph()->SetStart(start); Node* p0 = graph()->NewNode(common()->Parameter(0), start); Node* tv = graph()->NewNode(common()->Int32Constant(6)); Node* fv = graph()->NewNode(common()->Int32Constant(7)); Node* br = graph()->NewNode(common()->Branch(BranchHint::kFalse), p0, start); Node* t = graph()->NewNode(common()->IfTrue(), br); Node* f = graph()->NewNode(common()->IfFalse(), br); Node* m = graph()->NewNode(common()->Merge(2), t, f); Node* phi = graph()->NewNode(common()->Phi(MachineRepresentation::kTagged, 2), tv, fv, m); Node* ret = graph()->NewNode(common()->Return(), phi, start, start); Node* end = graph()->NewNode(common()->End(1), ret); graph()->SetEnd(end); Schedule* schedule = ComputeAndVerifySchedule(13); // Make sure the true block is marked as deferred. EXPECT_TRUE(schedule->block(t)->deferred()); EXPECT_FALSE(schedule->block(f)->deferred()); } TARGET_TEST_F(SchedulerTest, CallException) { Node* start = graph()->NewNode(common()->Start(1)); graph()->SetStart(start); Node* p0 = graph()->NewNode(common()->Parameter(0), start); Node* c1 = graph()->NewNode(&kMockCall, start); Node* ok1 = graph()->NewNode(common()->IfSuccess(), c1); Node* ex1 = graph()->NewNode( common()->IfException(IfExceptionHint::kLocallyUncaught), c1, c1); Node* c2 = graph()->NewNode(&kMockCall, ok1); Node* ok2 = graph()->NewNode(common()->IfSuccess(), c2); Node* ex2 = graph()->NewNode( common()->IfException(IfExceptionHint::kLocallyUncaught), c2, c2); Node* hdl = graph()->NewNode(common()->Merge(2), ex1, ex2); Node* m = graph()->NewNode(common()->Merge(2), ok2, hdl); Node* phi = graph()->NewNode(common()->Phi(MachineRepresentation::kTagged, 2), c2, p0, m); Node* ret = graph()->NewNode(common()->Return(), phi, start, m); Node* end = graph()->NewNode(common()->End(1), ret); graph()->SetEnd(end); Schedule* schedule = ComputeAndVerifySchedule(17); // Make sure the exception blocks as well as the handler are deferred. EXPECT_TRUE(schedule->block(ex1)->deferred()); EXPECT_TRUE(schedule->block(ex2)->deferred()); EXPECT_TRUE(schedule->block(hdl)->deferred()); EXPECT_FALSE(schedule->block(m)->deferred()); } TARGET_TEST_F(SchedulerTest, TailCall) { Node* start = graph()->NewNode(common()->Start(1)); graph()->SetStart(start); Node* p0 = graph()->NewNode(common()->Parameter(0), start); Node* call = graph()->NewNode(&kMockTailCall, p0, start, start); Node* end = graph()->NewNode(common()->End(1), call); graph()->SetEnd(end); ComputeAndVerifySchedule(4); } TARGET_TEST_F(SchedulerTest, Switch) { Node* start = graph()->NewNode(common()->Start(1)); graph()->SetStart(start); Node* p0 = graph()->NewNode(common()->Parameter(0), start); Node* sw = graph()->NewNode(common()->Switch(3), p0, start); Node* c0 = graph()->NewNode(common()->IfValue(0), sw); Node* v0 = graph()->NewNode(common()->Int32Constant(11)); Node* c1 = graph()->NewNode(common()->IfValue(1), sw); Node* v1 = graph()->NewNode(common()->Int32Constant(22)); Node* d = graph()->NewNode(common()->IfDefault(), sw); Node* vd = graph()->NewNode(common()->Int32Constant(33)); Node* m = graph()->NewNode(common()->Merge(3), c0, c1, d); Node* phi = graph()->NewNode(common()->Phi(MachineRepresentation::kWord32, 3), v0, v1, vd, m); Node* ret = graph()->NewNode(common()->Return(), phi, start, m); Node* end = graph()->NewNode(common()->End(1), ret); graph()->SetEnd(end); ComputeAndVerifySchedule(16); } TARGET_TEST_F(SchedulerTest, FloatingSwitch) { Node* start = graph()->NewNode(common()->Start(1)); graph()->SetStart(start); Node* p0 = graph()->NewNode(common()->Parameter(0), start); Node* sw = graph()->NewNode(common()->Switch(3), p0, start); Node* c0 = graph()->NewNode(common()->IfValue(0), sw); Node* v0 = graph()->NewNode(common()->Int32Constant(11)); Node* c1 = graph()->NewNode(common()->IfValue(1), sw); Node* v1 = graph()->NewNode(common()->Int32Constant(22)); Node* d = graph()->NewNode(common()->IfDefault(), sw); Node* vd = graph()->NewNode(common()->Int32Constant(33)); Node* m = graph()->NewNode(common()->Merge(3), c0, c1, d); Node* phi = graph()->NewNode(common()->Phi(MachineRepresentation::kWord32, 3), v0, v1, vd, m); Node* ret = graph()->NewNode(common()->Return(), phi, start, start); Node* end = graph()->NewNode(common()->End(1), ret); graph()->SetEnd(end); ComputeAndVerifySchedule(16); } TARGET_TEST_F(SchedulerTest, Terminate) { Node* start = graph()->NewNode(common()->Start(1)); graph()->SetStart(start); Node* loop = graph()->NewNode(common()->Loop(2), start, start); loop->ReplaceInput(1, loop); // self loop, NTL. Node* effect = graph()->NewNode(common()->EffectPhi(2), start, start, loop); effect->ReplaceInput(1, effect); // self loop. Node* terminate = graph()->NewNode(common()->Terminate(), effect, loop); Node* end = graph()->NewNode(common()->End(1), terminate); graph()->SetEnd(end); Schedule* schedule = ComputeAndVerifySchedule(6); BasicBlock* block = schedule->block(loop); EXPECT_EQ(block, schedule->block(effect)); EXPECT_GE(block->rpo_number(), 0); } } // namespace compiler } // namespace internal } // namespace v8