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 private final Parameters params;
032 private final int actualParamsSize;
033 private final StackValue[] remapValues;
034 private final int additionalShift;
035
036 public LocalVarRemapper(@NotNull Parameters params, int additionalShift) {
037 this.additionalShift = additionalShift;
038 this.params = params;
039
040 remapValues = new StackValue[params.getArgsSizeOnStack()];
041
042 int realSize = 0;
043 for (ParameterInfo info : params) {
044 Integer shift = params.getDeclarationSlot(info);
045 if (!info.isSkippedOrRemapped()) {
046 remapValues[shift] = StackValue.local(realSize, AsmTypes.OBJECT_TYPE);
047 realSize += info.getType().getSize();
048 }
049 else {
050 remapValues[shift] = info.isRemapped() ? info.getRemapValue() : null;
051 if (CapturedParamInfo.isSynthetic(info)) {
052 realSize += info.getType().getSize();
053 }
054 }
055 }
056
057 actualParamsSize = realSize;
058 }
059
060 @NotNull
061 private RemapInfo doRemap(int index) {
062 int remappedIndex;
063
064 if (index < params.getArgsSizeOnStack()) {
065 ParameterInfo info = params.getParameterByDeclarationSlot(index);
066 StackValue remapped = remapValues[index];
067 if (info.isSkipped || remapped == null) {
068 return new RemapInfo(info);
069 }
070 if (info.isRemapped()) {
071 return new RemapInfo(remapped, info, REMAPPED);
072 }
073 else {
074 remappedIndex = ((StackValue.Local) remapped).index;
075 }
076 }
077 else {
078 //captured params are not used directly in this inlined method, they are used in closure
079 remappedIndex = actualParamsSize - params.getArgsSizeOnStack() + index;
080 }
081
082 return new RemapInfo(StackValue.local(remappedIndex + additionalShift, AsmTypes.OBJECT_TYPE), null, SHIFT);
083 }
084
085 @NotNull
086 public RemapInfo remap(int index) {
087 RemapInfo info = doRemap(index);
088 if (FAIL == info.status) {
089 assert info.parameterInfo != null : "Parameter info should be not null";
090 throw new RuntimeException("Trying to access skipped parameter: " + info.parameterInfo.type + " at " +index);
091 }
092 return info;
093 }
094
095 public void visitIincInsn(int var, int increment, @NotNull MethodVisitor mv) {
096 RemapInfo remap = remap(var);
097 assert remap.value instanceof StackValue.Local : "Remapped value should be a local: " + remap.value;
098 mv.visitIincInsn(((StackValue.Local) remap.value).index, increment);
099 }
100
101 public void visitLocalVariable(
102 @NotNull String name,
103 @NotNull String desc,
104 @Nullable String signature,
105 @NotNull Label start,
106 @NotNull Label end,
107 int index,
108 MethodVisitor mv
109 ) {
110 RemapInfo info = doRemap(index);
111 //add entries only for shifted vars
112 if (SHIFT == info.status) {
113 mv.visitLocalVariable(name, desc, signature, start, end, ((StackValue.Local) info.value).index);
114 }
115 }
116
117 public void visitVarInsn(int opcode, int var, @NotNull InstructionAdapter mv) {
118 RemapInfo remapInfo = remap(var);
119 StackValue value = remapInfo.value;
120 if (value instanceof StackValue.Local) {
121 boolean isStore = InlineCodegenUtil.isStoreInstruction(opcode);
122 if (remapInfo.parameterInfo != null) {
123 //All remapped value parameters can't be rewritten except case of default ones.
124 //On remapping default parameter to actual value there is only one instruction that writes to it according to mask value
125 //but if such parameter remapped then it passed and this mask branch code never executed
126 //TODO add assertion about parameter default value: descriptor is required
127 opcode = value.type.getOpcode(isStore ? Opcodes.ISTORE : Opcodes.ILOAD);
128 }
129 mv.visitVarInsn(opcode, ((StackValue.Local) value).index);
130 if (remapInfo.parameterInfo != null && !isStore) {
131 StackValue.coerce(value.type, remapInfo.parameterInfo.type, mv);
132 }
133 }
134 else {
135 assert remapInfo.parameterInfo != null : "Non local value should have parameter info";
136 value.put(remapInfo.parameterInfo.type, mv);
137 }
138 }
139
140 public enum RemapStatus {
141 SHIFT,
142 REMAPPED,
143 FAIL
144 }
145
146 public static class RemapInfo {
147 public final StackValue value;
148 public final ParameterInfo parameterInfo;
149 public final RemapStatus status;
150
151 public RemapInfo(@NotNull StackValue value, @Nullable ParameterInfo parameterInfo, @NotNull RemapStatus remapStatus) {
152 this.value = value;
153 this.parameterInfo = parameterInfo;
154 this.status = remapStatus;
155 }
156
157 public RemapInfo(@NotNull ParameterInfo parameterInfo) {
158 this.value = null;
159 this.parameterInfo = parameterInfo;
160 this.status = FAIL;
161 }
162 }
163 }