/* * Copyright (C) 2015 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. */ public class Main { public static void main(String[] args) { $noinline$testWithNull(new Object[2]); $noinline$testWithUnknown(new Object[2], new Object()); $noinline$testWithSame(new Object[2]); $noinline$testWithSameRTI(); } // Known null can eliminate the type check in early stages. /// CHECK-START: void Main.$noinline$testWithNull(java.lang.Object[]) instruction_simplifier (before) /// CHECK: ArraySet needs_type_check:true can_trigger_gc:true /// CHECK-START: void Main.$noinline$testWithNull(java.lang.Object[]) instruction_simplifier (after) /// CHECK: ArraySet needs_type_check:false can_trigger_gc:false /// CHECK-START: void Main.$noinline$testWithNull(java.lang.Object[]) disassembly (after) /// CHECK: ArraySet needs_type_check:false can_trigger_gc:false public static void $noinline$testWithNull(Object[] o) { o[0] = null; } /// CHECK-START: void Main.$noinline$testWithUnknown(java.lang.Object[], java.lang.Object) disassembly (after) /// CHECK: ArraySet needs_type_check:true can_trigger_gc:true public static void $noinline$testWithUnknown(Object[] o, Object obj) { o[0] = obj; } // After GVN we know that we are setting values from the same array so there's no need for a type // check. /// CHECK-START: void Main.$noinline$testWithSame(java.lang.Object[]) instruction_simplifier$after_gvn (before) /// CHECK: ArraySet needs_type_check:true can_trigger_gc:true /// CHECK-START: void Main.$noinline$testWithSame(java.lang.Object[]) instruction_simplifier$after_gvn (after) /// CHECK: ArraySet needs_type_check:false can_trigger_gc:false /// CHECK-START: void Main.$noinline$testWithSame(java.lang.Object[]) disassembly (after) /// CHECK: ArraySet needs_type_check:false can_trigger_gc:false public static void $noinline$testWithSame(Object[] o) { o[0] = o[1]; } // We know that the array and the static Object have the same RTI in early stages. No need for a // type check. /// CHECK-START: java.lang.Object[] Main.$noinline$testWithSameRTI() instruction_simplifier (before) /// CHECK: ArraySet needs_type_check:true can_trigger_gc:true /// CHECK-START: java.lang.Object[] Main.$noinline$testWithSameRTI() instruction_simplifier (after) /// CHECK: ArraySet needs_type_check:false can_trigger_gc:false /// CHECK-START: java.lang.Object[] Main.$noinline$testWithSameRTI() disassembly (after) /// CHECK: ArraySet needs_type_check:false can_trigger_gc:false public static Object[] $noinline$testWithSameRTI() { Object[] arr = new Object[1]; arr[0] = static_obj; // Return so that LSE doesn't eliminate the ArraySet. return arr; } static Object static_obj; }