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.intrinsics;
018    
019    import com.intellij.psi.PsiElement;
020    import org.jetbrains.annotations.NotNull;
021    import org.jetbrains.jet.codegen.ExpressionCodegen;
022    import org.jetbrains.jet.codegen.StackValue;
023    import org.jetbrains.jet.lang.psi.JetExpression;
024    import org.jetbrains.jet.lang.resolve.java.AsmTypeConstants;
025    import org.jetbrains.org.objectweb.asm.Type;
026    import org.jetbrains.org.objectweb.asm.commons.InstructionAdapter;
027    
028    import java.util.List;
029    
030    import static org.jetbrains.jet.codegen.AsmUtil.genInvokeAppendMethod;
031    import static org.jetbrains.jet.codegen.AsmUtil.genStringBuilderConstructor;
032    import static org.jetbrains.jet.lang.resolve.java.AsmTypeConstants.JAVA_STRING_TYPE;
033    
034    public class Concat extends IntrinsicMethod {
035        @NotNull
036        @Override
037        public Type generateImpl(
038                @NotNull ExpressionCodegen codegen,
039                @NotNull InstructionAdapter v,
040                @NotNull Type returnType,
041                PsiElement element,
042                @NotNull List<JetExpression> arguments,
043                @NotNull StackValue receiver
044        ) {
045            if (receiver == StackValue.none()) {
046                // LHS + RHS
047                genStringBuilderConstructor(v);
048                codegen.invokeAppend(arguments.get(0));
049                codegen.invokeAppend(arguments.get(1));
050            }
051            else {
052                // LHS.plus(RHS)
053                receiver.put(AsmTypeConstants.OBJECT_TYPE, v);
054                genStringBuilderConstructor(v);
055                v.swap();
056                genInvokeAppendMethod(v, returnType);
057                codegen.invokeAppend(arguments.get(0));
058            }
059    
060            v.invokevirtual("java/lang/StringBuilder", "toString", "()Ljava/lang/String;", false);
061            return JAVA_STRING_TYPE;
062        }
063    }