/* * Copyright (C) 2014 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include "base/arena_allocator.h" #include "bounds_check_elimination.h" #include "builder.h" #include "gvn.h" #include "instruction_simplifier.h" #include "nodes.h" #include "optimizing_unit_test.h" #include "side_effects_analysis.h" #include "gtest/gtest.h" namespace art { static void RunSimplifierAndGvn(HGraph* graph) { InstructionSimplifier simplify(graph); simplify.Run(); SideEffectsAnalysis side_effects(graph); side_effects.Run(); GVNOptimization(graph, side_effects).Run(); } // if (i < 0) { array[i] = 1; // Can't eliminate. } // else if (i >= array.length) { array[i] = 1; // Can't eliminate. } // else { array[i] = 1; // Can eliminate. } TEST(BoundsCheckEliminationTest, NarrowingRangeArrayBoundsElimination) { ArenaPool pool; ArenaAllocator allocator(&pool); HGraph* graph = CreateGraph(&allocator); graph->SetHasBoundsChecks(true); HBasicBlock* entry = new (&allocator) HBasicBlock(graph); graph->AddBlock(entry); graph->SetEntryBlock(entry); HInstruction* parameter1 = new (&allocator) HParameterValue(0, Primitive::kPrimNot); // array HInstruction* parameter2 = new (&allocator) HParameterValue(0, Primitive::kPrimInt); // i entry->AddInstruction(parameter1); entry->AddInstruction(parameter2); HInstruction* constant_1 = graph->GetIntConstant(1); HInstruction* constant_0 = graph->GetIntConstant(0); HBasicBlock* block1 = new (&allocator) HBasicBlock(graph); graph->AddBlock(block1); HInstruction* cmp = new (&allocator) HGreaterThanOrEqual(parameter2, constant_0); HIf* if_inst = new (&allocator) HIf(cmp); block1->AddInstruction(cmp); block1->AddInstruction(if_inst); entry->AddSuccessor(block1); HBasicBlock* block2 = new (&allocator) HBasicBlock(graph); graph->AddBlock(block2); HNullCheck* null_check = new (&allocator) HNullCheck(parameter1, 0); HArrayLength* array_length = new (&allocator) HArrayLength(null_check); HBoundsCheck* bounds_check2 = new (&allocator) HBoundsCheck(parameter2, array_length, 0); HArraySet* array_set = new (&allocator) HArraySet( null_check, bounds_check2, constant_1, Primitive::kPrimInt, 0); block2->AddInstruction(null_check); block2->AddInstruction(array_length); block2->AddInstruction(bounds_check2); block2->AddInstruction(array_set); HBasicBlock* block3 = new (&allocator) HBasicBlock(graph); graph->AddBlock(block3); null_check = new (&allocator) HNullCheck(parameter1, 0); array_length = new (&allocator) HArrayLength(null_check); cmp = new (&allocator) HLessThan(parameter2, array_length); if_inst = new (&allocator) HIf(cmp); block3->AddInstruction(null_check); block3->AddInstruction(array_length); block3->AddInstruction(cmp); block3->AddInstruction(if_inst); HBasicBlock* block4 = new (&allocator) HBasicBlock(graph); graph->AddBlock(block4); null_check = new (&allocator) HNullCheck(parameter1, 0); array_length = new (&allocator) HArrayLength(null_check); HBoundsCheck* bounds_check4 = new (&allocator) HBoundsCheck(parameter2, array_length, 0); array_set = new (&allocator) HArraySet( null_check, bounds_check4, constant_1, Primitive::kPrimInt, 0); block4->AddInstruction(null_check); block4->AddInstruction(array_length); block4->AddInstruction(bounds_check4); block4->AddInstruction(array_set); HBasicBlock* block5 = new (&allocator) HBasicBlock(graph); graph->AddBlock(block5); null_check = new (&allocator) HNullCheck(parameter1, 0); array_length = new (&allocator) HArrayLength(null_check); HBoundsCheck* bounds_check5 = new (&allocator) HBoundsCheck(parameter2, array_length, 0); array_set = new (&allocator) HArraySet( null_check, bounds_check5, constant_1, Primitive::kPrimInt, 0); block5->AddInstruction(null_check); block5->AddInstruction(array_length); block5->AddInstruction(bounds_check5); block5->AddInstruction(array_set); HBasicBlock* exit = new (&allocator) HBasicBlock(graph); graph->AddBlock(exit); block2->AddSuccessor(exit); block4->AddSuccessor(exit); block5->AddSuccessor(exit); exit->AddInstruction(new (&allocator) HExit()); block1->AddSuccessor(block3); // True successor block1->AddSuccessor(block2); // False successor block3->AddSuccessor(block5); // True successor block3->AddSuccessor(block4); // False successor graph->BuildDominatorTree(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination(graph); bounds_check_elimination.Run(); ASSERT_FALSE(IsRemoved(bounds_check2)); ASSERT_FALSE(IsRemoved(bounds_check4)); ASSERT_TRUE(IsRemoved(bounds_check5)); } // if (i > 0) { // // Positive number plus MAX_INT will overflow and be negative. // int j = i + Integer.MAX_VALUE; // if (j < array.length) array[j] = 1; // Can't eliminate. // } TEST(BoundsCheckEliminationTest, OverflowArrayBoundsElimination) { ArenaPool pool; ArenaAllocator allocator(&pool); HGraph* graph = CreateGraph(&allocator); graph->SetHasBoundsChecks(true); HBasicBlock* entry = new (&allocator) HBasicBlock(graph); graph->AddBlock(entry); graph->SetEntryBlock(entry); HInstruction* parameter1 = new (&allocator) HParameterValue(0, Primitive::kPrimNot); // array HInstruction* parameter2 = new (&allocator) HParameterValue(0, Primitive::kPrimInt); // i entry->AddInstruction(parameter1); entry->AddInstruction(parameter2); HInstruction* constant_1 = graph->GetIntConstant(1); HInstruction* constant_0 = graph->GetIntConstant(0); HInstruction* constant_max_int = graph->GetIntConstant(INT_MAX); HBasicBlock* block1 = new (&allocator) HBasicBlock(graph); graph->AddBlock(block1); HInstruction* cmp = new (&allocator) HLessThanOrEqual(parameter2, constant_0); HIf* if_inst = new (&allocator) HIf(cmp); block1->AddInstruction(cmp); block1->AddInstruction(if_inst); entry->AddSuccessor(block1); HBasicBlock* block2 = new (&allocator) HBasicBlock(graph); graph->AddBlock(block2); HInstruction* add = new (&allocator) HAdd(Primitive::kPrimInt, parameter2, constant_max_int); HNullCheck* null_check = new (&allocator) HNullCheck(parameter1, 0); HArrayLength* array_length = new (&allocator) HArrayLength(null_check); HInstruction* cmp2 = new (&allocator) HGreaterThanOrEqual(add, array_length); if_inst = new (&allocator) HIf(cmp2); block2->AddInstruction(add); block2->AddInstruction(null_check); block2->AddInstruction(array_length); block2->AddInstruction(cmp2); block2->AddInstruction(if_inst); HBasicBlock* block3 = new (&allocator) HBasicBlock(graph); graph->AddBlock(block3); HBoundsCheck* bounds_check = new (&allocator) HBoundsCheck(add, array_length, 0); HArraySet* array_set = new (&allocator) HArraySet( null_check, bounds_check, constant_1, Primitive::kPrimInt, 0); block3->AddInstruction(bounds_check); block3->AddInstruction(array_set); HBasicBlock* exit = new (&allocator) HBasicBlock(graph); graph->AddBlock(exit); exit->AddInstruction(new (&allocator) HExit()); block1->AddSuccessor(exit); // true successor block1->AddSuccessor(block2); // false successor block2->AddSuccessor(exit); // true successor block2->AddSuccessor(block3); // false successor block3->AddSuccessor(exit); graph->BuildDominatorTree(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination(graph); bounds_check_elimination.Run(); ASSERT_FALSE(IsRemoved(bounds_check)); } // if (i < array.length) { // int j = i - Integer.MAX_VALUE; // j = j - Integer.MAX_VALUE; // j is (i+2) after substracting MAX_INT twice // if (j > 0) array[j] = 1; // Can't eliminate. // } TEST(BoundsCheckEliminationTest, UnderflowArrayBoundsElimination) { ArenaPool pool; ArenaAllocator allocator(&pool); HGraph* graph = CreateGraph(&allocator); graph->SetHasBoundsChecks(true); HBasicBlock* entry = new (&allocator) HBasicBlock(graph); graph->AddBlock(entry); graph->SetEntryBlock(entry); HInstruction* parameter1 = new (&allocator) HParameterValue(0, Primitive::kPrimNot); // array HInstruction* parameter2 = new (&allocator) HParameterValue(0, Primitive::kPrimInt); // i entry->AddInstruction(parameter1); entry->AddInstruction(parameter2); HInstruction* constant_1 = graph->GetIntConstant(1); HInstruction* constant_0 = graph->GetIntConstant(0); HInstruction* constant_max_int = graph->GetIntConstant(INT_MAX); HBasicBlock* block1 = new (&allocator) HBasicBlock(graph); graph->AddBlock(block1); HNullCheck* null_check = new (&allocator) HNullCheck(parameter1, 0); HArrayLength* array_length = new (&allocator) HArrayLength(null_check); HInstruction* cmp = new (&allocator) HGreaterThanOrEqual(parameter2, array_length); HIf* if_inst = new (&allocator) HIf(cmp); block1->AddInstruction(null_check); block1->AddInstruction(array_length); block1->AddInstruction(cmp); block1->AddInstruction(if_inst); entry->AddSuccessor(block1); HBasicBlock* block2 = new (&allocator) HBasicBlock(graph); graph->AddBlock(block2); HInstruction* sub1 = new (&allocator) HSub(Primitive::kPrimInt, parameter2, constant_max_int); HInstruction* sub2 = new (&allocator) HSub(Primitive::kPrimInt, sub1, constant_max_int); HInstruction* cmp2 = new (&allocator) HLessThanOrEqual(sub2, constant_0); if_inst = new (&allocator) HIf(cmp2); block2->AddInstruction(sub1); block2->AddInstruction(sub2); block2->AddInstruction(cmp2); block2->AddInstruction(if_inst); HBasicBlock* block3 = new (&allocator) HBasicBlock(graph); graph->AddBlock(block3); HBoundsCheck* bounds_check = new (&allocator) HBoundsCheck(sub2, array_length, 0); HArraySet* array_set = new (&allocator) HArraySet( null_check, bounds_check, constant_1, Primitive::kPrimInt, 0); block3->AddInstruction(bounds_check); block3->AddInstruction(array_set); HBasicBlock* exit = new (&allocator) HBasicBlock(graph); graph->AddBlock(exit); exit->AddInstruction(new (&allocator) HExit()); block1->AddSuccessor(exit); // true successor block1->AddSuccessor(block2); // false successor block2->AddSuccessor(exit); // true successor block2->AddSuccessor(block3); // false successor block3->AddSuccessor(exit); graph->BuildDominatorTree(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination(graph); bounds_check_elimination.Run(); ASSERT_FALSE(IsRemoved(bounds_check)); } // array[6] = 1; // Can't eliminate. // array[5] = 1; // Can eliminate. // array[4] = 1; // Can eliminate. TEST(BoundsCheckEliminationTest, ConstantArrayBoundsElimination) { ArenaPool pool; ArenaAllocator allocator(&pool); HGraph* graph = CreateGraph(&allocator); graph->SetHasBoundsChecks(true); HBasicBlock* entry = new (&allocator) HBasicBlock(graph); graph->AddBlock(entry); graph->SetEntryBlock(entry); HInstruction* parameter = new (&allocator) HParameterValue(0, Primitive::kPrimNot); entry->AddInstruction(parameter); HInstruction* constant_5 = graph->GetIntConstant(5); HInstruction* constant_4 = graph->GetIntConstant(4); HInstruction* constant_6 = graph->GetIntConstant(6); HInstruction* constant_1 = graph->GetIntConstant(1); HBasicBlock* block = new (&allocator) HBasicBlock(graph); graph->AddBlock(block); entry->AddSuccessor(block); HNullCheck* null_check = new (&allocator) HNullCheck(parameter, 0); HArrayLength* array_length = new (&allocator) HArrayLength(null_check); HBoundsCheck* bounds_check6 = new (&allocator) HBoundsCheck(constant_6, array_length, 0); HInstruction* array_set = new (&allocator) HArraySet( null_check, bounds_check6, constant_1, Primitive::kPrimInt, 0); block->AddInstruction(null_check); block->AddInstruction(array_length); block->AddInstruction(bounds_check6); block->AddInstruction(array_set); null_check = new (&allocator) HNullCheck(parameter, 0); array_length = new (&allocator) HArrayLength(null_check); HBoundsCheck* bounds_check5 = new (&allocator) HBoundsCheck(constant_5, array_length, 0); array_set = new (&allocator) HArraySet( null_check, bounds_check5, constant_1, Primitive::kPrimInt, 0); block->AddInstruction(null_check); block->AddInstruction(array_length); block->AddInstruction(bounds_check5); block->AddInstruction(array_set); null_check = new (&allocator) HNullCheck(parameter, 0); array_length = new (&allocator) HArrayLength(null_check); HBoundsCheck* bounds_check4 = new (&allocator) HBoundsCheck(constant_4, array_length, 0); array_set = new (&allocator) HArraySet( null_check, bounds_check4, constant_1, Primitive::kPrimInt, 0); block->AddInstruction(null_check); block->AddInstruction(array_length); block->AddInstruction(bounds_check4); block->AddInstruction(array_set); block->AddInstruction(new (&allocator) HGoto()); HBasicBlock* exit = new (&allocator) HBasicBlock(graph); graph->AddBlock(exit); block->AddSuccessor(exit); exit->AddInstruction(new (&allocator) HExit()); graph->BuildDominatorTree(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination(graph); bounds_check_elimination.Run(); ASSERT_FALSE(IsRemoved(bounds_check6)); ASSERT_TRUE(IsRemoved(bounds_check5)); ASSERT_TRUE(IsRemoved(bounds_check4)); } // for (int i=initial; iSetHasBoundsChecks(true); HBasicBlock* entry = new (allocator) HBasicBlock(graph); graph->AddBlock(entry); graph->SetEntryBlock(entry); HInstruction* parameter = new (allocator) HParameterValue(0, Primitive::kPrimNot); entry->AddInstruction(parameter); HInstruction* constant_initial = graph->GetIntConstant(initial); HInstruction* constant_increment = graph->GetIntConstant(increment); HInstruction* constant_10 = graph->GetIntConstant(10); HBasicBlock* block = new (allocator) HBasicBlock(graph); graph->AddBlock(block); entry->AddSuccessor(block); block->AddInstruction(new (allocator) HGoto()); HBasicBlock* loop_header = new (allocator) HBasicBlock(graph); HBasicBlock* loop_body = new (allocator) HBasicBlock(graph); HBasicBlock* exit = new (allocator) HBasicBlock(graph); graph->AddBlock(loop_header); graph->AddBlock(loop_body); graph->AddBlock(exit); block->AddSuccessor(loop_header); loop_header->AddSuccessor(exit); // true successor loop_header->AddSuccessor(loop_body); // false successor loop_body->AddSuccessor(loop_header); HPhi* phi = new (allocator) HPhi(allocator, 0, 0, Primitive::kPrimInt); HInstruction* null_check = new (allocator) HNullCheck(parameter, 0); HInstruction* array_length = new (allocator) HArrayLength(null_check); HInstruction* cmp = nullptr; if (cond == kCondGE) { cmp = new (allocator) HGreaterThanOrEqual(phi, array_length); } else { DCHECK(cond == kCondGT); cmp = new (allocator) HGreaterThan(phi, array_length); } HInstruction* if_inst = new (allocator) HIf(cmp); loop_header->AddPhi(phi); loop_header->AddInstruction(null_check); loop_header->AddInstruction(array_length); loop_header->AddInstruction(cmp); loop_header->AddInstruction(if_inst); phi->AddInput(constant_initial); null_check = new (allocator) HNullCheck(parameter, 0); array_length = new (allocator) HArrayLength(null_check); *bounds_check = new (allocator) HBoundsCheck(phi, array_length, 0); HInstruction* array_set = new (allocator) HArraySet( null_check, *bounds_check, constant_10, Primitive::kPrimInt, 0); HInstruction* add = new (allocator) HAdd(Primitive::kPrimInt, phi, constant_increment); loop_body->AddInstruction(null_check); loop_body->AddInstruction(array_length); loop_body->AddInstruction(*bounds_check); loop_body->AddInstruction(array_set); loop_body->AddInstruction(add); loop_body->AddInstruction(new (allocator) HGoto()); phi->AddInput(add); exit->AddInstruction(new (allocator) HExit()); return graph; } TEST(BoundsCheckEliminationTest, LoopArrayBoundsElimination1) { ArenaPool pool; ArenaAllocator allocator(&pool); // for (int i=0; iBuildDominatorTree(); graph->AnalyzeNaturalLoops(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination(graph); bounds_check_elimination.Run(); ASSERT_TRUE(IsRemoved(bounds_check)); // for (int i=1; iBuildDominatorTree(); graph->AnalyzeNaturalLoops(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination_with_initial_1(graph); bounds_check_elimination_with_initial_1.Run(); ASSERT_TRUE(IsRemoved(bounds_check)); // for (int i=-1; iBuildDominatorTree(); graph->AnalyzeNaturalLoops(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination_with_initial_minus_1(graph); bounds_check_elimination_with_initial_minus_1.Run(); ASSERT_FALSE(IsRemoved(bounds_check)); // for (int i=0; i<=array.length; i++) { array[i] = 10; // Can't eliminate. } graph = BuildSSAGraph1(&allocator, &bounds_check, 0, 1, kCondGT); graph->BuildDominatorTree(); graph->AnalyzeNaturalLoops(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination_with_greater_than(graph); bounds_check_elimination_with_greater_than.Run(); ASSERT_FALSE(IsRemoved(bounds_check)); // for (int i=0; iBuildDominatorTree(); graph->AnalyzeNaturalLoops(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination_with_increment_2(graph); bounds_check_elimination_with_increment_2.Run(); ASSERT_FALSE(IsRemoved(bounds_check)); // for (int i=1; iBuildDominatorTree(); graph->AnalyzeNaturalLoops(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination_with_increment_2_from_1(graph); bounds_check_elimination_with_increment_2_from_1.Run(); ASSERT_TRUE(IsRemoved(bounds_check)); } // for (int i=array.length; i>0; i+=increment) { array[i-1] = 10; } static HGraph* BuildSSAGraph2(ArenaAllocator* allocator, HInstruction** bounds_check, int initial, int increment = -1, IfCondition cond = kCondLE) { HGraph* graph = CreateGraph(allocator); graph->SetHasBoundsChecks(true); HBasicBlock* entry = new (allocator) HBasicBlock(graph); graph->AddBlock(entry); graph->SetEntryBlock(entry); HInstruction* parameter = new (allocator) HParameterValue(0, Primitive::kPrimNot); entry->AddInstruction(parameter); HInstruction* constant_initial = graph->GetIntConstant(initial); HInstruction* constant_increment = graph->GetIntConstant(increment); HInstruction* constant_minus_1 = graph->GetIntConstant(-1); HInstruction* constant_10 = graph->GetIntConstant(10); HBasicBlock* block = new (allocator) HBasicBlock(graph); graph->AddBlock(block); entry->AddSuccessor(block); HInstruction* null_check = new (allocator) HNullCheck(parameter, 0); HInstruction* array_length = new (allocator) HArrayLength(null_check); block->AddInstruction(null_check); block->AddInstruction(array_length); block->AddInstruction(new (allocator) HGoto()); HBasicBlock* loop_header = new (allocator) HBasicBlock(graph); HBasicBlock* loop_body = new (allocator) HBasicBlock(graph); HBasicBlock* exit = new (allocator) HBasicBlock(graph); graph->AddBlock(loop_header); graph->AddBlock(loop_body); graph->AddBlock(exit); block->AddSuccessor(loop_header); loop_header->AddSuccessor(exit); // true successor loop_header->AddSuccessor(loop_body); // false successor loop_body->AddSuccessor(loop_header); HPhi* phi = new (allocator) HPhi(allocator, 0, 0, Primitive::kPrimInt); HInstruction* cmp = nullptr; if (cond == kCondLE) { cmp = new (allocator) HLessThanOrEqual(phi, constant_initial); } else { DCHECK(cond == kCondLT); cmp = new (allocator) HLessThan(phi, constant_initial); } HInstruction* if_inst = new (allocator) HIf(cmp); loop_header->AddPhi(phi); loop_header->AddInstruction(cmp); loop_header->AddInstruction(if_inst); phi->AddInput(array_length); HInstruction* add = new (allocator) HAdd(Primitive::kPrimInt, phi, constant_minus_1); null_check = new (allocator) HNullCheck(parameter, 0); array_length = new (allocator) HArrayLength(null_check); *bounds_check = new (allocator) HBoundsCheck(add, array_length, 0); HInstruction* array_set = new (allocator) HArraySet( null_check, *bounds_check, constant_10, Primitive::kPrimInt, 0); HInstruction* add_phi = new (allocator) HAdd(Primitive::kPrimInt, phi, constant_increment); loop_body->AddInstruction(add); loop_body->AddInstruction(null_check); loop_body->AddInstruction(array_length); loop_body->AddInstruction(*bounds_check); loop_body->AddInstruction(array_set); loop_body->AddInstruction(add_phi); loop_body->AddInstruction(new (allocator) HGoto()); phi->AddInput(add); exit->AddInstruction(new (allocator) HExit()); return graph; } TEST(BoundsCheckEliminationTest, LoopArrayBoundsElimination2) { ArenaPool pool; ArenaAllocator allocator(&pool); // for (int i=array.length; i>0; i--) { array[i-1] = 10; // Can eliminate with gvn. } HInstruction* bounds_check = nullptr; HGraph* graph = BuildSSAGraph2(&allocator, &bounds_check, 0); graph->BuildDominatorTree(); graph->AnalyzeNaturalLoops(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination(graph); bounds_check_elimination.Run(); ASSERT_TRUE(IsRemoved(bounds_check)); // for (int i=array.length; i>1; i--) { array[i-1] = 10; // Can eliminate. } graph = BuildSSAGraph2(&allocator, &bounds_check, 1); graph->BuildDominatorTree(); graph->AnalyzeNaturalLoops(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination_with_initial_1(graph); bounds_check_elimination_with_initial_1.Run(); ASSERT_TRUE(IsRemoved(bounds_check)); // for (int i=array.length; i>-1; i--) { array[i-1] = 10; // Can't eliminate. } graph = BuildSSAGraph2(&allocator, &bounds_check, -1); graph->BuildDominatorTree(); graph->AnalyzeNaturalLoops(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination_with_initial_minus_1(graph); bounds_check_elimination_with_initial_minus_1.Run(); ASSERT_FALSE(IsRemoved(bounds_check)); // for (int i=array.length; i>=0; i--) { array[i-1] = 10; // Can't eliminate. } graph = BuildSSAGraph2(&allocator, &bounds_check, 0, -1, kCondLT); graph->BuildDominatorTree(); graph->AnalyzeNaturalLoops(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination_with_less_than(graph); bounds_check_elimination_with_less_than.Run(); ASSERT_FALSE(IsRemoved(bounds_check)); // for (int i=array.length; i>0; i-=2) { array[i-1] = 10; // Can eliminate. } graph = BuildSSAGraph2(&allocator, &bounds_check, 0, -2); graph->BuildDominatorTree(); graph->AnalyzeNaturalLoops(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination_increment_minus_2(graph); bounds_check_elimination_increment_minus_2.Run(); ASSERT_TRUE(IsRemoved(bounds_check)); } // int[] array = new int[10]; // for (int i=0; i<10; i+=increment) { array[i] = 10; } static HGraph* BuildSSAGraph3(ArenaAllocator* allocator, HInstruction** bounds_check, int initial, int increment, IfCondition cond) { HGraph* graph = CreateGraph(allocator); graph->SetHasBoundsChecks(true); HBasicBlock* entry = new (allocator) HBasicBlock(graph); graph->AddBlock(entry); graph->SetEntryBlock(entry); HInstruction* constant_10 = graph->GetIntConstant(10); HInstruction* constant_initial = graph->GetIntConstant(initial); HInstruction* constant_increment = graph->GetIntConstant(increment); HBasicBlock* block = new (allocator) HBasicBlock(graph); graph->AddBlock(block); entry->AddSuccessor(block); HInstruction* new_array = new (allocator) HNewArray(constant_10, 0, Primitive::kPrimInt, kQuickAllocArray); block->AddInstruction(new_array); block->AddInstruction(new (allocator) HGoto()); HBasicBlock* loop_header = new (allocator) HBasicBlock(graph); HBasicBlock* loop_body = new (allocator) HBasicBlock(graph); HBasicBlock* exit = new (allocator) HBasicBlock(graph); graph->AddBlock(loop_header); graph->AddBlock(loop_body); graph->AddBlock(exit); block->AddSuccessor(loop_header); loop_header->AddSuccessor(exit); // true successor loop_header->AddSuccessor(loop_body); // false successor loop_body->AddSuccessor(loop_header); HPhi* phi = new (allocator) HPhi(allocator, 0, 0, Primitive::kPrimInt); HInstruction* cmp = nullptr; if (cond == kCondGE) { cmp = new (allocator) HGreaterThanOrEqual(phi, constant_10); } else { DCHECK(cond == kCondGT); cmp = new (allocator) HGreaterThan(phi, constant_10); } HInstruction* if_inst = new (allocator) HIf(cmp); loop_header->AddPhi(phi); loop_header->AddInstruction(cmp); loop_header->AddInstruction(if_inst); phi->AddInput(constant_initial); HNullCheck* null_check = new (allocator) HNullCheck(new_array, 0); HArrayLength* array_length = new (allocator) HArrayLength(null_check); *bounds_check = new (allocator) HBoundsCheck(phi, array_length, 0); HInstruction* array_set = new (allocator) HArraySet( null_check, *bounds_check, constant_10, Primitive::kPrimInt, 0); HInstruction* add = new (allocator) HAdd(Primitive::kPrimInt, phi, constant_increment); loop_body->AddInstruction(null_check); loop_body->AddInstruction(array_length); loop_body->AddInstruction(*bounds_check); loop_body->AddInstruction(array_set); loop_body->AddInstruction(add); loop_body->AddInstruction(new (allocator) HGoto()); phi->AddInput(add); exit->AddInstruction(new (allocator) HExit()); return graph; } TEST(BoundsCheckEliminationTest, LoopArrayBoundsElimination3) { ArenaPool pool; ArenaAllocator allocator(&pool); // int[] array = new int[10]; // for (int i=0; i<10; i++) { array[i] = 10; // Can eliminate. } HInstruction* bounds_check = nullptr; HGraph* graph = BuildSSAGraph3(&allocator, &bounds_check, 0, 1, kCondGE); graph->BuildDominatorTree(); graph->AnalyzeNaturalLoops(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination(graph); bounds_check_elimination.Run(); ASSERT_TRUE(IsRemoved(bounds_check)); // int[] array = new int[10]; // for (int i=1; i<10; i++) { array[i] = 10; // Can eliminate. } graph = BuildSSAGraph3(&allocator, &bounds_check, 1, 1, kCondGE); graph->BuildDominatorTree(); graph->AnalyzeNaturalLoops(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination_with_initial_1(graph); bounds_check_elimination_with_initial_1.Run(); ASSERT_TRUE(IsRemoved(bounds_check)); // int[] array = new int[10]; // for (int i=0; i<=10; i++) { array[i] = 10; // Can't eliminate. } graph = BuildSSAGraph3(&allocator, &bounds_check, 0, 1, kCondGT); graph->BuildDominatorTree(); graph->AnalyzeNaturalLoops(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination_with_greater_than(graph); bounds_check_elimination_with_greater_than.Run(); ASSERT_FALSE(IsRemoved(bounds_check)); // int[] array = new int[10]; // for (int i=1; i<10; i+=8) { array[i] = 10; // Can eliminate. } graph = BuildSSAGraph3(&allocator, &bounds_check, 1, 8, kCondGE); graph->BuildDominatorTree(); graph->AnalyzeNaturalLoops(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination_increment_8(graph); bounds_check_elimination_increment_8.Run(); ASSERT_TRUE(IsRemoved(bounds_check)); } // for (int i=initial; iSetHasBoundsChecks(true); HBasicBlock* entry = new (allocator) HBasicBlock(graph); graph->AddBlock(entry); graph->SetEntryBlock(entry); HInstruction* parameter = new (allocator) HParameterValue(0, Primitive::kPrimNot); entry->AddInstruction(parameter); HInstruction* constant_initial = graph->GetIntConstant(initial); HInstruction* constant_1 = graph->GetIntConstant(1); HInstruction* constant_10 = graph->GetIntConstant(10); HInstruction* constant_minus_1 = graph->GetIntConstant(-1); HBasicBlock* block = new (allocator) HBasicBlock(graph); graph->AddBlock(block); entry->AddSuccessor(block); block->AddInstruction(new (allocator) HGoto()); HBasicBlock* loop_header = new (allocator) HBasicBlock(graph); HBasicBlock* loop_body = new (allocator) HBasicBlock(graph); HBasicBlock* exit = new (allocator) HBasicBlock(graph); graph->AddBlock(loop_header); graph->AddBlock(loop_body); graph->AddBlock(exit); block->AddSuccessor(loop_header); loop_header->AddSuccessor(exit); // true successor loop_header->AddSuccessor(loop_body); // false successor loop_body->AddSuccessor(loop_header); HPhi* phi = new (allocator) HPhi(allocator, 0, 0, Primitive::kPrimInt); HInstruction* null_check = new (allocator) HNullCheck(parameter, 0); HInstruction* array_length = new (allocator) HArrayLength(null_check); HInstruction* cmp = nullptr; if (cond == kCondGE) { cmp = new (allocator) HGreaterThanOrEqual(phi, array_length); } else if (cond == kCondGT) { cmp = new (allocator) HGreaterThan(phi, array_length); } HInstruction* if_inst = new (allocator) HIf(cmp); loop_header->AddPhi(phi); loop_header->AddInstruction(null_check); loop_header->AddInstruction(array_length); loop_header->AddInstruction(cmp); loop_header->AddInstruction(if_inst); phi->AddInput(constant_initial); null_check = new (allocator) HNullCheck(parameter, 0); array_length = new (allocator) HArrayLength(null_check); HInstruction* sub = new (allocator) HSub(Primitive::kPrimInt, array_length, phi); HInstruction* add_minus_1 = new (allocator) HAdd(Primitive::kPrimInt, sub, constant_minus_1); *bounds_check = new (allocator) HBoundsCheck(add_minus_1, array_length, 0); HInstruction* array_set = new (allocator) HArraySet( null_check, *bounds_check, constant_10, Primitive::kPrimInt, 0); HInstruction* add = new (allocator) HAdd(Primitive::kPrimInt, phi, constant_1); loop_body->AddInstruction(null_check); loop_body->AddInstruction(array_length); loop_body->AddInstruction(sub); loop_body->AddInstruction(add_minus_1); loop_body->AddInstruction(*bounds_check); loop_body->AddInstruction(array_set); loop_body->AddInstruction(add); loop_body->AddInstruction(new (allocator) HGoto()); phi->AddInput(add); exit->AddInstruction(new (allocator) HExit()); return graph; } TEST(BoundsCheckEliminationTest, LoopArrayBoundsElimination4) { ArenaPool pool; ArenaAllocator allocator(&pool); // for (int i=0; iBuildDominatorTree(); graph->AnalyzeNaturalLoops(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination(graph); bounds_check_elimination.Run(); ASSERT_TRUE(IsRemoved(bounds_check)); // for (int i=1; iBuildDominatorTree(); graph->AnalyzeNaturalLoops(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination_with_initial_1(graph); bounds_check_elimination_with_initial_1.Run(); ASSERT_TRUE(IsRemoved(bounds_check)); // for (int i=0; i<=array.length; i++) { array[array.length-i] = 10; // Can't eliminate. } graph = BuildSSAGraph4(&allocator, &bounds_check, 0, kCondGT); graph->BuildDominatorTree(); graph->AnalyzeNaturalLoops(); RunSimplifierAndGvn(graph); BoundsCheckElimination bounds_check_elimination_with_greater_than(graph); bounds_check_elimination_with_greater_than.Run(); ASSERT_FALSE(IsRemoved(bounds_check)); } // Bubble sort: // (Every array access bounds-check can be eliminated.) // for (int i=0; i array[j+1]) { // int temp = array[j+1]; // array[j+1] = array[j]; // array[j] = temp; // } // } // } TEST(BoundsCheckEliminationTest, BubbleSortArrayBoundsElimination) { ArenaPool pool; ArenaAllocator allocator(&pool); HGraph* graph = CreateGraph(&allocator); graph->SetHasBoundsChecks(true); HBasicBlock* entry = new (&allocator) HBasicBlock(graph); graph->AddBlock(entry); graph->SetEntryBlock(entry); HInstruction* parameter = new (&allocator) HParameterValue(0, Primitive::kPrimNot); entry->AddInstruction(parameter); HInstruction* constant_0 = graph->GetIntConstant(0); HInstruction* constant_minus_1 = graph->GetIntConstant(-1); HInstruction* constant_1 = graph->GetIntConstant(1); HBasicBlock* block = new (&allocator) HBasicBlock(graph); graph->AddBlock(block); entry->AddSuccessor(block); block->AddInstruction(new (&allocator) HGoto()); HBasicBlock* exit = new (&allocator) HBasicBlock(graph); graph->AddBlock(exit); exit->AddInstruction(new (&allocator) HExit()); HBasicBlock* outer_header = new (&allocator) HBasicBlock(graph); graph->AddBlock(outer_header); HPhi* phi_i = new (&allocator) HPhi(&allocator, 0, 0, Primitive::kPrimInt); HNullCheck* null_check = new (&allocator) HNullCheck(parameter, 0); HArrayLength* array_length = new (&allocator) HArrayLength(null_check); HAdd* add = new (&allocator) HAdd(Primitive::kPrimInt, array_length, constant_minus_1); HInstruction* cmp = new (&allocator) HGreaterThanOrEqual(phi_i, add); HIf* if_inst = new (&allocator) HIf(cmp); outer_header->AddPhi(phi_i); outer_header->AddInstruction(null_check); outer_header->AddInstruction(array_length); outer_header->AddInstruction(add); outer_header->AddInstruction(cmp); outer_header->AddInstruction(if_inst); phi_i->AddInput(constant_0); HBasicBlock* inner_header = new (&allocator) HBasicBlock(graph); graph->AddBlock(inner_header); HPhi* phi_j = new (&allocator) HPhi(&allocator, 0, 0, Primitive::kPrimInt); null_check = new (&allocator) HNullCheck(parameter, 0); array_length = new (&allocator) HArrayLength(null_check); HSub* sub = new (&allocator) HSub(Primitive::kPrimInt, array_length, phi_i); add = new (&allocator) HAdd(Primitive::kPrimInt, sub, constant_minus_1); cmp = new (&allocator) HGreaterThanOrEqual(phi_j, add); if_inst = new (&allocator) HIf(cmp); inner_header->AddPhi(phi_j); inner_header->AddInstruction(null_check); inner_header->AddInstruction(array_length); inner_header->AddInstruction(sub); inner_header->AddInstruction(add); inner_header->AddInstruction(cmp); inner_header->AddInstruction(if_inst); phi_j->AddInput(constant_0); HBasicBlock* inner_body_compare = new (&allocator) HBasicBlock(graph); graph->AddBlock(inner_body_compare); null_check = new (&allocator) HNullCheck(parameter, 0); array_length = new (&allocator) HArrayLength(null_check); HBoundsCheck* bounds_check1 = new (&allocator) HBoundsCheck(phi_j, array_length, 0); HArrayGet* array_get_j = new (&allocator) HArrayGet(null_check, bounds_check1, Primitive::kPrimInt); inner_body_compare->AddInstruction(null_check); inner_body_compare->AddInstruction(array_length); inner_body_compare->AddInstruction(bounds_check1); inner_body_compare->AddInstruction(array_get_j); HInstruction* j_plus_1 = new (&allocator) HAdd(Primitive::kPrimInt, phi_j, constant_1); null_check = new (&allocator) HNullCheck(parameter, 0); array_length = new (&allocator) HArrayLength(null_check); HBoundsCheck* bounds_check2 = new (&allocator) HBoundsCheck(j_plus_1, array_length, 0); HArrayGet* array_get_j_plus_1 = new (&allocator) HArrayGet(null_check, bounds_check2, Primitive::kPrimInt); cmp = new (&allocator) HGreaterThanOrEqual(array_get_j, array_get_j_plus_1); if_inst = new (&allocator) HIf(cmp); inner_body_compare->AddInstruction(j_plus_1); inner_body_compare->AddInstruction(null_check); inner_body_compare->AddInstruction(array_length); inner_body_compare->AddInstruction(bounds_check2); inner_body_compare->AddInstruction(array_get_j_plus_1); inner_body_compare->AddInstruction(cmp); inner_body_compare->AddInstruction(if_inst); HBasicBlock* inner_body_swap = new (&allocator) HBasicBlock(graph); graph->AddBlock(inner_body_swap); j_plus_1 = new (&allocator) HAdd(Primitive::kPrimInt, phi_j, constant_1); // temp = array[j+1] null_check = new (&allocator) HNullCheck(parameter, 0); array_length = new (&allocator) HArrayLength(null_check); HInstruction* bounds_check3 = new (&allocator) HBoundsCheck(j_plus_1, array_length, 0); array_get_j_plus_1 = new (&allocator) HArrayGet(null_check, bounds_check3, Primitive::kPrimInt); inner_body_swap->AddInstruction(j_plus_1); inner_body_swap->AddInstruction(null_check); inner_body_swap->AddInstruction(array_length); inner_body_swap->AddInstruction(bounds_check3); inner_body_swap->AddInstruction(array_get_j_plus_1); // array[j+1] = array[j] null_check = new (&allocator) HNullCheck(parameter, 0); array_length = new (&allocator) HArrayLength(null_check); HInstruction* bounds_check4 = new (&allocator) HBoundsCheck(phi_j, array_length, 0); array_get_j = new (&allocator) HArrayGet(null_check, bounds_check4, Primitive::kPrimInt); inner_body_swap->AddInstruction(null_check); inner_body_swap->AddInstruction(array_length); inner_body_swap->AddInstruction(bounds_check4); inner_body_swap->AddInstruction(array_get_j); null_check = new (&allocator) HNullCheck(parameter, 0); array_length = new (&allocator) HArrayLength(null_check); HInstruction* bounds_check5 = new (&allocator) HBoundsCheck(j_plus_1, array_length, 0); HArraySet* array_set_j_plus_1 = new (&allocator) HArraySet(null_check, bounds_check5, array_get_j, Primitive::kPrimInt, 0); inner_body_swap->AddInstruction(null_check); inner_body_swap->AddInstruction(array_length); inner_body_swap->AddInstruction(bounds_check5); inner_body_swap->AddInstruction(array_set_j_plus_1); // array[j] = temp null_check = new (&allocator) HNullCheck(parameter, 0); array_length = new (&allocator) HArrayLength(null_check); HInstruction* bounds_check6 = new (&allocator) HBoundsCheck(phi_j, array_length, 0); HArraySet* array_set_j = new (&allocator) HArraySet(null_check, bounds_check6, array_get_j_plus_1, Primitive::kPrimInt, 0); inner_body_swap->AddInstruction(null_check); inner_body_swap->AddInstruction(array_length); inner_body_swap->AddInstruction(bounds_check6); inner_body_swap->AddInstruction(array_set_j); inner_body_swap->AddInstruction(new (&allocator) HGoto()); HBasicBlock* inner_body_add = new (&allocator) HBasicBlock(graph); graph->AddBlock(inner_body_add); add = new (&allocator) HAdd(Primitive::kPrimInt, phi_j, constant_1); inner_body_add->AddInstruction(add); inner_body_add->AddInstruction(new (&allocator) HGoto()); phi_j->AddInput(add); HBasicBlock* outer_body_add = new (&allocator) HBasicBlock(graph); graph->AddBlock(outer_body_add); add = new (&allocator) HAdd(Primitive::kPrimInt, phi_i, constant_1); outer_body_add->AddInstruction(add); outer_body_add->AddInstruction(new (&allocator) HGoto()); phi_i->AddInput(add); block->AddSuccessor(outer_header); outer_header->AddSuccessor(exit); outer_header->AddSuccessor(inner_header); inner_header->AddSuccessor(outer_body_add); inner_header->AddSuccessor(inner_body_compare); inner_body_compare->AddSuccessor(inner_body_add); inner_body_compare->AddSuccessor(inner_body_swap); inner_body_swap->AddSuccessor(inner_body_add); inner_body_add->AddSuccessor(inner_header); outer_body_add->AddSuccessor(outer_header); graph->BuildDominatorTree(); graph->AnalyzeNaturalLoops(); RunSimplifierAndGvn(graph); // gvn should remove the same bounds check. ASSERT_FALSE(IsRemoved(bounds_check1)); ASSERT_FALSE(IsRemoved(bounds_check2)); ASSERT_TRUE(IsRemoved(bounds_check3)); ASSERT_TRUE(IsRemoved(bounds_check4)); ASSERT_TRUE(IsRemoved(bounds_check5)); ASSERT_TRUE(IsRemoved(bounds_check6)); BoundsCheckElimination bounds_check_elimination(graph); bounds_check_elimination.Run(); ASSERT_TRUE(IsRemoved(bounds_check1)); ASSERT_TRUE(IsRemoved(bounds_check2)); ASSERT_TRUE(IsRemoved(bounds_check3)); ASSERT_TRUE(IsRemoved(bounds_check4)); ASSERT_TRUE(IsRemoved(bounds_check5)); ASSERT_TRUE(IsRemoved(bounds_check6)); } } // namespace art