/*
* $Id$
*
* Copyright (C) 2003-2014 JNode.org
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; If not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
package org.jnode.vm.compiler.ir.quad;
import org.jnode.vm.compiler.ir.AddressingMode;
import org.jnode.vm.compiler.ir.CodeGenerator;
import org.jnode.vm.compiler.ir.Constant;
import org.jnode.vm.compiler.ir.IRBasicBlock;
import org.jnode.vm.compiler.ir.Location;
import org.jnode.vm.compiler.ir.Operand;
import org.jnode.vm.compiler.ir.RegisterLocation;
import org.jnode.vm.compiler.ir.StackLocation;
import org.jnode.vm.compiler.ir.Variable;
import static org.jnode.vm.compiler.ir.AddressingMode.CONSTANT;
import static org.jnode.vm.compiler.ir.AddressingMode.REGISTER;
import static org.jnode.vm.compiler.ir.AddressingMode.STACK;
import static org.jnode.vm.compiler.ir.quad.BranchCondition.IF_ACMPEQ;
import static org.jnode.vm.compiler.ir.quad.BranchCondition.IF_ACMPNE;
import static org.jnode.vm.compiler.ir.quad.BranchCondition.IF_ICMPEQ;
import static org.jnode.vm.compiler.ir.quad.BranchCondition.IF_ICMPNE;
/**
* @author Madhu Siddalingaiah
* @author Levente S\u00e1ntha
*/
public class ConditionalBranchQuad<T> extends BranchQuad<T> {
private BranchCondition condition;
private boolean commutative;
private Operand<T>[] refs;
private enum Mode {
MODE_CC(CONSTANT, CONSTANT), MODE_CR(CONSTANT, REGISTER), MODE_CS(
CONSTANT, STACK), MODE_RC(REGISTER, CONSTANT), MODE_RR(
REGISTER, REGISTER), MODE_RS(REGISTER, STACK), MODE_SC(STACK,
CONSTANT), MODE_SR(STACK, REGISTER), MODE_SS(STACK, STACK);
private final AddressingMode m1;
private final AddressingMode m2;
private Mode(AddressingMode m1, AddressingMode m2) {
this.m1 = m1;
this.m2 = m2;
}
public static Mode valueOf(AddressingMode m1, AddressingMode m2) {
for (Mode m : values()) {
if ((m.m1 == m1) && (m.m2 == m2)) {
return m;
}
}
throw new IllegalArgumentException();
}
}
/**
* @param address
* @param targetAddress
*/
public ConditionalBranchQuad(int address, IRBasicBlock<T> block,
int varIndex1, BranchCondition condition, int varIndex2, int targetAddress) {
super(address, block, targetAddress);
if (!condition.isBinary()) {
throw new IllegalArgumentException("can't use that condition here");
}
this.condition = condition;
this.commutative = condition == IF_ICMPEQ || condition == IF_ICMPNE
|| condition == IF_ACMPEQ || condition == IF_ACMPNE;
refs = new Operand[]{getOperand(varIndex1), getOperand(varIndex2)};
}
public ConditionalBranchQuad(int address, IRBasicBlock<T> block, int varIndex,
BranchCondition condition, int targetAddress) {
super(address, block, targetAddress);
if (!condition.isUnary()) {
throw new IllegalArgumentException("can't use that condition here");
}
this.condition = condition;
this.commutative = condition == IF_ICMPEQ || condition == IF_ICMPNE
|| condition == IF_ACMPEQ || condition == IF_ACMPNE;
refs = new Operand[]{getOperand(varIndex)};
}
/**
* @see org.jnode.vm.compiler.ir.quad.Quad#getDefinedOp()
*/
public Operand<T> getDefinedOp() {
return null;
}
/**
* @see org.jnode.vm.compiler.ir.quad.Quad#getReferencedOps()
*/
public Operand<T>[] getReferencedOps() {
return refs;
}
/**
* @return the first operand
*/
public Operand<T> getOperand1() {
return refs[0];
}
/**
* @return the second operand
*/
public Operand<T> getOperand2() {
return refs[1];
}
/**
* @return the branch condition
*/
public BranchCondition getCondition() {
return condition;
}
public String toString() {
if (condition.isBinary()) {
return getAddress() + ": if " + refs[0].toString() + ' '
+ condition.getCondition() + ' ' + refs[1].toString()
+ " goto " + getTargetBlock();
} else {
return getAddress() + ": if " + refs[0].toString() + ' '
+ condition.getCondition() + " goto " + getTargetBlock();
}
}
public void doPass2() {
refs[0] = refs[0].simplify();
if (refs.length > 1 && refs[1] != null) {
refs[1] = refs[1].simplify();
}
}
public void generateCode(CodeGenerator<T> cg) {
// cg.generateCodeFor(this);
if (condition.isBinary()) {
generateCodeForBinary(cg);
} else {
generateCodeForUnary(cg);
}
}
public void generateCodeForUnary(CodeGenerator<T> cg) {
if (refs[0] instanceof Variable) {
Location<T> varLoc = ((Variable<T>) refs[0]).getLocation();
if (varLoc instanceof RegisterLocation) {
RegisterLocation<T> vregLoc = (RegisterLocation<T>) varLoc;
cg.generateCodeFor(this, condition, vregLoc.getRegister());
} else if (varLoc instanceof StackLocation) {
StackLocation<T> stackLoc = (StackLocation<T>) varLoc;
cg.generateCodeFor(this, condition, stackLoc.getDisplacement());
} else {
throw new IllegalArgumentException("Unknown location: "
+ varLoc);
}
} else if (refs[0] instanceof Constant) {
// this probably won't happen, is should be folded earlier
Constant<T> con = (Constant<T>) refs[0];
cg.generateCodeFor(this, condition, con);
} else {
throw new IllegalArgumentException("Unknown operand: " + refs[0]);
}
}
/**
* Code generation is complicated by the permutations of addressing modes.
* This is not as nice as it could be, but it could be worse!
*
* @see org.jnode.vm.compiler.ir.quad.Quad#generateCode(org.jnode.vm.compiler.ir.CodeGenerator)
*/
public void generateCodeForBinary(CodeGenerator<T> cg) {
cg.checkLabel(getAddress());
AddressingMode op1Mode = refs[0].getAddressingMode();
AddressingMode op2Mode = refs[1].getAddressingMode();
Object reg2 = null;
if (op1Mode == REGISTER) {
Variable<T> var = (Variable<T>) refs[0];
RegisterLocation<T> regLoc = (RegisterLocation<T>) var.getLocation();
reg2 = regLoc.getRegister();
}
Object reg3 = null;
if (op2Mode == REGISTER) {
Variable<T> var = (Variable<T>) refs[1];
RegisterLocation<T> regLoc = (RegisterLocation<T>) var.getLocation();
reg3 = regLoc.getRegister();
}
int disp2 = 0;
if (op1Mode == STACK) {
Variable<T> var = (Variable<T>) refs[0];
StackLocation<T> stackLoc = (StackLocation<T>) var.getLocation();
disp2 = stackLoc.getDisplacement();
}
int disp3 = 0;
if (op2Mode == STACK) {
Variable<T> var = (Variable<T>) refs[1];
StackLocation<T> stackLoc = (StackLocation<T>) var.getLocation();
disp3 = stackLoc.getDisplacement();
}
Constant<T> c2 = null;
if (op1Mode == CONSTANT) {
c2 = (Constant<T>) refs[0];
}
Constant<T> c3 = null;
if (op2Mode == CONSTANT) {
c3 = (Constant<T>) refs[1];
}
final Mode aMode = Mode.valueOf(op1Mode, op2Mode);
switch (aMode) {
case MODE_CC:
cg.generateCodeFor(this, c2, condition, c3);
break;
case MODE_CR:
if (commutative && !cg.supports3AddrOps()) {
cg.generateCodeFor(this, reg3, condition, c2);
} else {
cg.generateCodeFor(this, c2, condition, reg3);
}
break;
case MODE_CS:
cg.generateCodeFor(this, c2, condition, disp3);
break;
case MODE_RC:
cg.generateCodeFor(this, reg2, condition, c3);
break;
case MODE_RR:
if (commutative && !cg.supports3AddrOps()) {
cg.generateCodeFor(this, reg3, condition, reg2);
} else {
cg.generateCodeFor(this, reg2, condition, reg3);
}
break;
case MODE_RS:
cg.generateCodeFor(this, reg2, condition, disp3);
break;
case MODE_SC:
cg.generateCodeFor(this, disp2, condition, c3);
break;
case MODE_SR:
if (commutative && !cg.supports3AddrOps()) {
cg.generateCodeFor(this, reg3, condition, disp2);
} else {
cg.generateCodeFor(this, disp2, condition, reg3);
}
break;
case MODE_SS:
cg.generateCodeFor(this, disp2, condition, disp3);
break;
default:
throw new IllegalArgumentException("Undefined addressing mode: "
+ aMode);
}
}
}