/*
* Copyright 2003-2010 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.codehaus.groovy.classgen.asm.sc;
import org.codehaus.groovy.ast.ClassHelper;
import org.codehaus.groovy.ast.ClassNode;
import org.codehaus.groovy.ast.Parameter;
import org.codehaus.groovy.ast.expr.ArgumentListExpression;
import org.codehaus.groovy.ast.expr.Expression;
import org.codehaus.groovy.ast.expr.MethodCallExpression;
import org.codehaus.groovy.ast.stmt.BlockStatement;
import org.codehaus.groovy.ast.stmt.ForStatement;
import org.codehaus.groovy.classgen.asm.*;
import org.codehaus.groovy.transform.stc.StaticTypeCheckingSupport;
import org.objectweb.asm.Label;
import org.objectweb.asm.MethodVisitor;
import static org.objectweb.asm.Opcodes.*;
/**
* A class to write out the optimized statements
* @author <a href="mailto:blackdrag@gmx.org">Jochen "blackdrag" Theodorou</a>
*/
public class StaticTypesStatementWriter extends StatementWriter {
private static final ClassNode ITERABLE_CLASSNODE = ClassHelper.make(Iterable.class);
private StaticTypesWriterController controller;
public StaticTypesStatementWriter(StaticTypesWriterController controller) {
super(controller);
this.controller = controller;
}
@Override
public void writeBlockStatement(BlockStatement statement) {
controller.switchToFastPath();
super.writeBlockStatement(statement);
controller.switchToSlowPath();
}
@Override
protected void writeForInLoop(final ForStatement loop) {
controller.getAcg().onLineNumber(loop,"visitForLoop");
writeStatementLabel(loop);
CompileStack compileStack = controller.getCompileStack();
MethodVisitor mv = controller.getMethodVisitor();
OperandStack operandStack = controller.getOperandStack();
compileStack.pushLoop(loop.getVariableScope(), loop.getStatementLabels());
// Declare the loop counter.
BytecodeVariable variable = compileStack.defineVariable(loop.getVariable(), false);
// Identify type of collection
TypeChooser typeChooser = controller.getTypeChooser();
Expression collectionExpression = loop.getCollectionExpression();
ClassNode collectionType = typeChooser.resolveType(collectionExpression, controller.getClassNode());
if (StaticTypeCheckingSupport.implementsInterfaceOrIsSubclassOf(collectionType,ITERABLE_CLASSNODE)) {
MethodCallExpression iterator = new MethodCallExpression(collectionExpression, "iterator", new ArgumentListExpression());
iterator.setMethodTarget(collectionType.getMethod("iterator", Parameter.EMPTY_ARRAY));
iterator.setImplicitThis(false);
iterator.visit(controller.getAcg());
} else {
collectionExpression.visit(controller.getAcg());
mv.visitMethodInsn(INVOKESTATIC, "org/codehaus/groovy/runtime/DefaultGroovyMethods", "iterator", "(Ljava/lang/Object;)Ljava/util/Iterator;", false);
operandStack.replace(ClassHelper.Iterator_TYPE);
}
// Then get the iterator and generate the loop control
final int iteratorIdx = compileStack.defineTemporaryVariable("iterator", ClassHelper.Iterator_TYPE, true);
Label continueLabel = compileStack.getContinueLabel();
Label breakLabel = compileStack.getBreakLabel();
mv.visitLabel(continueLabel);
mv.visitVarInsn(ALOAD, iteratorIdx);
writeIteratorHasNext(mv);
// note: ifeq tests for ==0, a boolean is 0 if it is false
mv.visitJumpInsn(IFEQ, breakLabel);
mv.visitVarInsn(ALOAD, iteratorIdx);
writeIteratorNext(mv);
operandStack.push(ClassHelper.OBJECT_TYPE);
operandStack.storeVar(variable);
// Generate the loop body
loop.getLoopBlock().visit(controller.getAcg());
mv.visitJumpInsn(GOTO, continueLabel);
mv.visitLabel(breakLabel);
compileStack.pop();
}
}