001 /*
002 * Copyright 2010-2015 JetBrains s.r.o.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017 package org.jetbrains.kotlin.codegen.inline;
018
019 import org.jetbrains.annotations.NotNull;
020 import org.jetbrains.annotations.Nullable;
021 import org.jetbrains.kotlin.codegen.StackValue;
022 import org.jetbrains.kotlin.resolve.jvm.AsmTypes;
023 import org.jetbrains.org.objectweb.asm.Label;
024 import org.jetbrains.org.objectweb.asm.MethodVisitor;
025 import org.jetbrains.org.objectweb.asm.Opcodes;
026 import org.jetbrains.org.objectweb.asm.commons.InstructionAdapter;
027
028 import static org.jetbrains.kotlin.codegen.inline.LocalVarRemapper.RemapStatus.*;
029
030 public class LocalVarRemapper {
031
032 private final Parameters params;
033 private final int actualParamsSize;
034
035 private final StackValue[] remapValues;
036 private final int additionalShift;
037
038 public LocalVarRemapper(Parameters params, int additionalShift) {
039 this.additionalShift = additionalShift;
040 this.params = params;
041
042 remapValues = new StackValue [params.getArgsSizeOnStack()];
043
044 int realSize = 0;
045 for (ParameterInfo info : params) {
046 Integer shift = params.getDeclarationSlot(info);
047 if (!info.isSkippedOrRemapped()) {
048 remapValues[shift] = StackValue.local(realSize, AsmTypes.OBJECT_TYPE);
049 realSize += info.getType().getSize();
050 }
051 else {
052 remapValues[shift] = info.isRemapped() ? info.getRemapValue() : null;
053 }
054 }
055
056 actualParamsSize = realSize;
057 }
058
059 public RemapInfo doRemap(int index) {
060 int remappedIndex;
061
062 if (index < params.getArgsSizeOnStack()) {
063 ParameterInfo info = params.getParameterByDeclarationSlot(index);
064 StackValue remapped = remapValues[index];
065 if (info.isSkipped || remapped == null) {
066 return new RemapInfo(info);
067 }
068 if (info.isRemapped()) {
069 return new RemapInfo(remapped, info, REMAPPED);
070 } else {
071 remappedIndex = ((StackValue.Local)remapped).index;
072 }
073 } else {
074 remappedIndex = actualParamsSize - params.getArgsSizeOnStack() + index; //captured params not used directly in this inlined method, they used in closure
075 }
076
077 return new RemapInfo(StackValue.local(remappedIndex + additionalShift, AsmTypes.OBJECT_TYPE), null, SHIFT);
078 }
079
080 public RemapInfo remap(int index) {
081 RemapInfo info = doRemap(index);
082 if (FAIL == info.status) {
083 assert info.parameterInfo != null : "Parameter info should be not null";
084 throw new RuntimeException("Trying to access skipped parameter: " + info.parameterInfo.type + " at " +index);
085 }
086 return info;
087 }
088
089 public void visitIincInsn(int var, int increment, MethodVisitor mv) {
090 RemapInfo remap = remap(var);
091 assert remap.value instanceof StackValue.Local;
092 mv.visitIincInsn(((StackValue.Local) remap.value).index, increment);
093 }
094
095 public void visitLocalVariable(String name, String desc, String signature, Label start, Label end, int index, MethodVisitor mv) {
096 RemapInfo info = doRemap(index);
097 //add entries only for shifted vars
098 if (SHIFT == info.status) {
099 int newIndex = ((StackValue.Local) info.value).index;
100 if (newIndex != 0 && "this".equals(name)) {
101 /*skip additional this for now*/
102 return;
103 }
104 mv.visitLocalVariable(name, desc, signature, start, end, newIndex);
105 }
106 }
107
108
109 public void visitVarInsn(int opcode, int var, InstructionAdapter mv) {
110 RemapInfo remapInfo = remap(var);
111 StackValue value = remapInfo.value;
112 if (value instanceof StackValue.Local) {
113 if (remapInfo.parameterInfo != null) {
114 //All remapped value parameters can't be rewritten except case of default ones.
115 //On remapping default parameter to actual value there is only one instruction that writes to it according to mask value
116 //but if such parameter remapped then it passed and this mask branch code never executed
117 //TODO add assertion about parameter default value: descriptor is required
118 opcode = value.type.getOpcode(InlineCodegenUtil.isStoreInstruction(opcode) ? Opcodes.ISTORE : Opcodes.ILOAD);
119 }
120 mv.visitVarInsn(opcode, ((StackValue.Local) value).index);
121 if (remapInfo.parameterInfo != null) {
122 StackValue.coerce(value.type, remapInfo.parameterInfo.type, mv);
123 }
124 } else {
125 assert remapInfo.parameterInfo != null : "Non local value should have parameter info";
126 value.put(remapInfo.parameterInfo.type, mv);
127 }
128 }
129
130 public enum RemapStatus {
131 SHIFT,
132 REMAPPED,
133 FAIL
134 }
135
136 public static class RemapInfo {
137 public final StackValue value;
138 public final ParameterInfo parameterInfo;
139 public final RemapStatus status;
140
141 public RemapInfo(@NotNull StackValue value, @Nullable ParameterInfo info, RemapStatus remapStatus) {
142 this.value = value;
143 parameterInfo = info;
144 this.status = remapStatus;
145 }
146
147 public RemapInfo(@NotNull ParameterInfo info) {
148 this.value = null;
149 parameterInfo = info;
150 this.status = FAIL;
151 }
152 }
153 }