/*
* 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 com.facebook.presto.byteCode.instruction;
import com.facebook.presto.byteCode.ByteCodeNode;
import com.facebook.presto.byteCode.ByteCodeVisitor;
import com.facebook.presto.byteCode.ParameterizedType;
import com.facebook.presto.byteCode.Variable;
import com.google.common.base.Objects;
import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableList;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Type;
import java.util.List;
import static com.facebook.presto.byteCode.OpCode.ILOAD;
import static com.facebook.presto.byteCode.OpCode.ISTORE;
public abstract class VariableInstruction
implements InstructionNode
{
public static InstructionNode loadVariable(int slot)
{
return new LoadVariableInstruction(new Variable("unknown", slot, ParameterizedType.type(Object.class)));
}
public static InstructionNode loadVariable(Variable variable)
{
return new LoadVariableInstruction(variable);
}
public static InstructionNode storeVariable(Variable variable)
{
return new StoreVariableInstruction(variable);
}
public static InstructionNode incrementVariable(Variable variable, byte increment)
{
return new IncrementVariableInstruction(variable, increment);
}
private final Variable variable;
private VariableInstruction(Variable variable)
{
this.variable = variable;
}
public Variable getVariable()
{
return variable;
}
@Override
public List<ByteCodeNode> getChildNodes()
{
return ImmutableList.of();
}
@Override
public <T> T accept(ByteCodeNode parent, ByteCodeVisitor<T> visitor)
{
return visitor.visitVariableInstruction(parent, this);
}
@Override
public String toString()
{
return Objects.toStringHelper(this)
.add("variable", variable)
.toString();
}
public static class LoadVariableInstruction
extends VariableInstruction
{
public LoadVariableInstruction(Variable variable)
{
super(variable);
}
@Override
public void accept(MethodVisitor visitor)
{
visitor.visitVarInsn(Type.getType(getVariable().getType().getType()).getOpcode(ILOAD.getOpCode()), getVariable().getSlot());
}
@Override
public <T> T accept(ByteCodeNode parent, ByteCodeVisitor<T> visitor)
{
return visitor.visitLoadVariable(parent, this);
}
}
public static class StoreVariableInstruction
extends VariableInstruction
{
public StoreVariableInstruction(Variable variable)
{
super(variable);
}
@Override
public void accept(MethodVisitor visitor)
{
visitor.visitVarInsn(Type.getType(getVariable().getType().getType()).getOpcode(ISTORE.getOpCode()), getVariable().getSlot());
}
@Override
public <T> T accept(ByteCodeNode parent, ByteCodeVisitor<T> visitor)
{
return visitor.visitStoreVariable(parent, this);
}
}
public static class IncrementVariableInstruction
extends VariableInstruction
{
private final byte increment;
public IncrementVariableInstruction(Variable variable, byte increment)
{
super(variable);
String type = variable.getType().getClassName();
Preconditions.checkArgument(ImmutableList.of("byte", "short", "int").contains(type), "variable must be an byte, short or int, but is %s", type);
this.increment = increment;
}
public byte getIncrement()
{
return increment;
}
@Override
public void accept(MethodVisitor visitor)
{
visitor.visitIincInsn(getVariable().getSlot(), increment);
}
@Override
public <T> T accept(ByteCodeNode parent, ByteCodeVisitor<T> visitor)
{
return visitor.visitIncrementVariable(parent, this);
}
}
}