001    /*
002     * Copyright 2010-2013 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.jet.codegen.inline;
018    
019    import org.jetbrains.annotations.NotNull;
020    import org.jetbrains.annotations.Nullable;
021    import org.jetbrains.org.objectweb.asm.Opcodes;
022    import org.jetbrains.org.objectweb.asm.tree.AbstractInsnNode;
023    import org.jetbrains.org.objectweb.asm.tree.FieldInsnNode;
024    import org.jetbrains.org.objectweb.asm.tree.MethodNode;
025    import org.jetbrains.jet.codegen.StackValue;
026    
027    import java.util.Collection;
028    import java.util.List;
029    
030    public class FieldRemapper {
031    
032        private final String lambdaInternalName;
033    
034        protected FieldRemapper parent;
035    
036        private final Parameters params;
037    
038        public FieldRemapper(@Nullable String lambdaInternalName, @Nullable FieldRemapper parent, @NotNull Parameters methodParams) {
039            this.lambdaInternalName = lambdaInternalName;
040            this.parent = parent;
041            params = methodParams;
042        }
043    
044        protected boolean canProcess(@NotNull String fieldOwner, String fieldName, boolean isFolding) {
045            return fieldOwner.equals(getLambdaInternalName()) &&
046                   //don't process general field of anonymous objects
047                   InlineCodegenUtil.isCapturedFieldName(fieldName);
048        }
049    
050        @Nullable
051        public AbstractInsnNode foldFieldAccessChainIfNeeded(
052                @NotNull List<AbstractInsnNode> capturedFieldAccess,
053                @NotNull MethodNode node
054        ) {
055            if (capturedFieldAccess.size() == 1) {
056                //just aload
057                return null;
058            }
059    
060            return foldFieldAccessChainIfNeeded(capturedFieldAccess, 1, node);
061        }
062    
063        @Nullable
064        private AbstractInsnNode foldFieldAccessChainIfNeeded(
065                @NotNull List<AbstractInsnNode> capturedFieldAccess,
066                int currentInstruction,
067                @NotNull MethodNode node
068        ) {
069            AbstractInsnNode transformed = null;
070            boolean checkParent = !isRoot() && currentInstruction < capturedFieldAccess.size() - 1;
071            if (checkParent) {
072                transformed = parent.foldFieldAccessChainIfNeeded(capturedFieldAccess, currentInstruction + 1, node);
073            }
074    
075            if (transformed == null) {
076                //if parent couldn't transform
077                FieldInsnNode insnNode = (FieldInsnNode) capturedFieldAccess.get(currentInstruction);
078                if (canProcess(insnNode.owner, insnNode.name, true)) {
079                    insnNode.name = "$$$" + insnNode.name;
080                    insnNode.setOpcode(Opcodes.GETSTATIC);
081    
082                    AbstractInsnNode next = capturedFieldAccess.get(0);
083                    while (next != insnNode) {
084                        AbstractInsnNode toDelete = next;
085                        next = next.getNext();
086                        node.instructions.remove(toDelete);
087                    }
088    
089                    transformed = capturedFieldAccess.get(capturedFieldAccess.size() - 1);
090                }
091            }
092    
093            return transformed;
094        }
095    
096        public CapturedParamInfo findField(@NotNull FieldInsnNode fieldInsnNode) {
097            return findField(fieldInsnNode, params.getCaptured());
098        }
099    
100        @Nullable
101        protected CapturedParamInfo findField(@NotNull FieldInsnNode fieldInsnNode, @NotNull Collection<CapturedParamInfo> captured) {
102            for (CapturedParamInfo valueDescriptor : captured) {
103                if (valueDescriptor.getOriginalFieldName().equals(fieldInsnNode.name) && fieldInsnNode.owner.equals(valueDescriptor.getContainingLambdaName())) {
104                    return valueDescriptor;
105                }
106            }
107            return null;
108        }
109    
110        public FieldRemapper getParent() {
111            return parent;
112        }
113    
114        public String getLambdaInternalName() {
115            return lambdaInternalName;
116        }
117    
118        public boolean isRoot() {
119            return parent == null;
120        }
121    
122        @Nullable
123        public StackValue getFieldForInline(@NotNull FieldInsnNode node, @Nullable StackValue prefix) {
124            CapturedParamInfo field = MethodInliner.findCapturedField(node, this);
125            return field.getRemapValue();
126        }
127    
128        public boolean isInsideInliningLambda() {
129            return !isRoot() && parent.isInsideInliningLambda();
130        }
131    }