| /* |
| * 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 "prepare_for_register_allocation.h" |
| |
| namespace art { |
| |
| void PrepareForRegisterAllocation::Run() { |
| // Order does not matter. |
| for (HReversePostOrderIterator it(*GetGraph()); !it.Done(); it.Advance()) { |
| HBasicBlock* block = it.Current(); |
| // No need to visit the phis. |
| for (HInstructionIterator inst_it(block->GetInstructions()); !inst_it.Done(); |
| inst_it.Advance()) { |
| inst_it.Current()->Accept(this); |
| } |
| } |
| } |
| |
| void PrepareForRegisterAllocation::VisitNullCheck(HNullCheck* check) { |
| check->ReplaceWith(check->InputAt(0)); |
| } |
| |
| void PrepareForRegisterAllocation::VisitDivZeroCheck(HDivZeroCheck* check) { |
| check->ReplaceWith(check->InputAt(0)); |
| } |
| |
| void PrepareForRegisterAllocation::VisitBoundsCheck(HBoundsCheck* check) { |
| check->ReplaceWith(check->InputAt(0)); |
| } |
| |
| void PrepareForRegisterAllocation::VisitBoundType(HBoundType* bound_type) { |
| bound_type->ReplaceWith(bound_type->InputAt(0)); |
| bound_type->GetBlock()->RemoveInstruction(bound_type); |
| } |
| |
| void PrepareForRegisterAllocation::VisitClinitCheck(HClinitCheck* check) { |
| HLoadClass* cls = check->GetLoadClass(); |
| check->ReplaceWith(cls); |
| if (check->GetPrevious() == cls) { |
| // Pass the initialization duty to the `HLoadClass` instruction, |
| // and remove the instruction from the graph. |
| cls->SetMustGenerateClinitCheck(); |
| check->GetBlock()->RemoveInstruction(check); |
| } |
| } |
| |
| void PrepareForRegisterAllocation::VisitCondition(HCondition* condition) { |
| bool needs_materialization = false; |
| if (!condition->GetUses().HasOnlyOneUse() || !condition->GetEnvUses().IsEmpty()) { |
| needs_materialization = true; |
| } else { |
| HInstruction* user = condition->GetUses().GetFirst()->GetUser(); |
| if (!user->IsIf() && !user->IsDeoptimize()) { |
| needs_materialization = true; |
| } else { |
| // TODO: if there is no intervening instructions with side-effect between this condition |
| // and the If instruction, we should move the condition just before the If. |
| if (condition->GetNext() != user) { |
| needs_materialization = true; |
| } |
| } |
| } |
| if (!needs_materialization) { |
| condition->ClearNeedsMaterialization(); |
| } |
| } |
| |
| void PrepareForRegisterAllocation::VisitInvokeStaticOrDirect(HInvokeStaticOrDirect* invoke) { |
| if (invoke->IsStaticWithExplicitClinitCheck()) { |
| size_t last_input_index = invoke->InputCount() - 1; |
| HInstruction* last_input = invoke->InputAt(last_input_index); |
| DCHECK(last_input->IsLoadClass()) << last_input->DebugName(); |
| |
| // Remove a load class instruction as last input of a static |
| // invoke, which has been added (along with a clinit check, |
| // removed by PrepareForRegisterAllocation::VisitClinitCheck |
| // previously) by the graph builder during the creation of the |
| // static invoke instruction, but is no longer required at this |
| // stage (i.e., after inlining has been performed). |
| invoke->RemoveLoadClassAsLastInput(); |
| |
| // If the load class instruction is no longer used, remove it from |
| // the graph. |
| if (!last_input->HasUses()) { |
| last_input->GetBlock()->RemoveInstruction(last_input); |
| } |
| } |
| } |
| |
| } // namespace art |