content: /*
   * Copyright (C) 2020 ActiveJ LLC.
   *
   * 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 io.activej.codegen.expression.impl;
  
  import io.activej.codegen.Context;
  import io.activej.codegen.expression.Expression;
  import io.activej.codegen.operation.CompareOperation;
  import io.activej.common.annotation.ExposedInternals;
  import org.objectweb.asm.Label;
  import org.objectweb.asm.Type;
  import org.objectweb.asm.commons.GeneratorAdapter;
  import org.objectweb.asm.commons.Method;
  
  import static io.activej.codegen.operation.CompareOperation.*;
  import static io.activej.codegen.util.TypeChecks.checkType;
  import static io.activej.codegen.util.TypeChecks.isAssignable;
  import static io.activej.codegen.util.Utils.invokeVirtualOrInterface;
  import static io.activej.codegen.util.Utils.isPrimitiveType;
  import static org.objectweb.asm.Type.BOOLEAN_TYPE;
  import static org.objectweb.asm.Type.INT_TYPE;
  
  /**
   * Defines methods for comparing functions
   */
  @ExposedInternals
  public final class IfObjCmp implements Expression {
  	public final Expression left;
  	public final Expression right;
  	public final CompareOperation operation;
  	public final Expression expressionTrue;
  	public final Expression expressionFalse;
  
  	public IfObjCmp(CompareOperation operation, Expression left, Expression right, Expression expressionTrue, Expression expressionFalse) {
  		this.left = left;
  		this.right = right;
  		this.operation = operation;
  		this.expressionTrue = expressionTrue;
  		this.expressionFalse = expressionFalse;
  	}
  
  	@Override
  	public Type load(Context ctx) {
  		GeneratorAdapter g = ctx.getGeneratorAdapter();
  		Label labelTrue = new Label();
  		Label labelExit = new Label();
  
  		Type leftType = left.load(ctx);
  		checkType(leftType, isAssignable());
  
  		Type rightType = right.load(ctx);
  		checkType(rightType, isAssignable());
  
  		if (!leftType.equals(rightType))
  			throw new IllegalArgumentException("Types of compared values should match");
  
  		if (isPrimitiveType(leftType)) {
  			g.ifCmp(leftType, operation.opCode, labelTrue);
  		} else {
  			if (operation == REF_EQ || operation == REF_NE) {
  				g.ifCmp(leftType, operation.opCode, labelTrue);
  			} else if (operation == EQ || operation == NE) {
  				invokeVirtualOrInterface(ctx, leftType, new Method("equals", BOOLEAN_TYPE, new Type[]{Type.getType(Object.class)}));
  				g.ifZCmp(operation == EQ ? GeneratorAdapter.NE : GeneratorAdapter.EQ, labelTrue);
  			} else {
  				invokeVirtualOrInterface(ctx, leftType, new Method("compareTo", INT_TYPE, new Type[]{Type.getType(Object.class)}));
  				g.ifZCmp(operation.opCode, labelTrue);
  			}
  		}
  
  		Type typeFalse = expressionFalse.load(ctx);
  		g.goTo(labelExit);
  
  		g.mark(labelTrue);
  		Type typeTrue = expressionTrue.load(ctx);
  
  		g.mark(labelExit);
  
  		return ctx.unifyTypes(typeFalse, typeTrue);
  	}
  }
  