1 /* 2 * Copyright (C) 2015 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 public class Main { main(String[] args)18 public static void main(String[] args) { 19 $noinline$testWithNull(new Object[2]); 20 $noinline$testWithUnknown(new Object[2], new Object()); 21 $noinline$testWithSame(new Object[2]); 22 $noinline$testWithSameRTI(); 23 } 24 25 // Known null can eliminate the type check in early stages. 26 27 /// CHECK-START: void Main.$noinline$testWithNull(java.lang.Object[]) instruction_simplifier (before) 28 /// CHECK: ArraySet needs_type_check:true can_trigger_gc:true 29 30 /// CHECK-START: void Main.$noinline$testWithNull(java.lang.Object[]) instruction_simplifier (after) 31 /// CHECK: ArraySet needs_type_check:false can_trigger_gc:false 32 33 /// CHECK-START: void Main.$noinline$testWithNull(java.lang.Object[]) disassembly (after) 34 /// CHECK: ArraySet needs_type_check:false can_trigger_gc:false $noinline$testWithNull(Object[] o)35 public static void $noinline$testWithNull(Object[] o) { 36 o[0] = null; 37 } 38 39 /// CHECK-START: void Main.$noinline$testWithUnknown(java.lang.Object[], java.lang.Object) disassembly (after) 40 /// CHECK: ArraySet needs_type_check:true can_trigger_gc:true $noinline$testWithUnknown(Object[] o, Object obj)41 public static void $noinline$testWithUnknown(Object[] o, Object obj) { 42 o[0] = obj; 43 } 44 45 // After GVN we know that we are setting values from the same array so there's no need for a type 46 // check. 47 48 /// CHECK-START: void Main.$noinline$testWithSame(java.lang.Object[]) instruction_simplifier$after_gvn (before) 49 /// CHECK: ArraySet needs_type_check:true can_trigger_gc:true 50 51 /// CHECK-START: void Main.$noinline$testWithSame(java.lang.Object[]) instruction_simplifier$after_gvn (after) 52 /// CHECK: ArraySet needs_type_check:false can_trigger_gc:false 53 54 /// CHECK-START: void Main.$noinline$testWithSame(java.lang.Object[]) disassembly (after) 55 /// CHECK: ArraySet needs_type_check:false can_trigger_gc:false $noinline$testWithSame(Object[] o)56 public static void $noinline$testWithSame(Object[] o) { 57 o[0] = o[1]; 58 } 59 60 // We know that the array and the static Object have the same RTI in early stages. No need for a 61 // type check. 62 63 /// CHECK-START: java.lang.Object[] Main.$noinline$testWithSameRTI() instruction_simplifier (before) 64 /// CHECK: ArraySet needs_type_check:true can_trigger_gc:true 65 66 /// CHECK-START: java.lang.Object[] Main.$noinline$testWithSameRTI() instruction_simplifier (after) 67 /// CHECK: ArraySet needs_type_check:false can_trigger_gc:false 68 69 /// CHECK-START: java.lang.Object[] Main.$noinline$testWithSameRTI() disassembly (after) 70 /// CHECK: ArraySet needs_type_check:false can_trigger_gc:false $noinline$testWithSameRTI()71 public static Object[] $noinline$testWithSameRTI() { 72 Object[] arr = new Object[1]; 73 arr[0] = static_obj; 74 // Return so that LSE doesn't eliminate the ArraySet. 75 return arr; 76 } 77 78 static Object static_obj; 79 } 80