/*
 * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code 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 General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package com.oracle.graal.compiler.ptx;

import static com.oracle.graal.api.code.ValueUtil.*;
import static com.oracle.graal.api.meta.Value.*;
import static com.oracle.graal.lir.ptx.PTXArithmetic.*;
import static com.oracle.graal.lir.ptx.PTXBitManipulationOp.IntrinsicOpcode.*;
import static com.oracle.graal.lir.ptx.PTXCompare.*;

import com.oracle.graal.api.code.*;
import com.oracle.graal.api.meta.*;
import com.oracle.graal.asm.*;
import com.oracle.graal.compiler.gen.*;
import com.oracle.graal.debug.Debug;
import com.oracle.graal.graph.*;
import com.oracle.graal.lir.*;
import com.oracle.graal.lir.StandardOp.JumpOp;
import com.oracle.graal.lir.ptx.*;
import com.oracle.graal.lir.ptx.PTXArithmetic.Op1Stack;
import com.oracle.graal.lir.ptx.PTXArithmetic.Op2Reg;
import com.oracle.graal.lir.ptx.PTXArithmetic.Op2Stack;
import com.oracle.graal.lir.ptx.PTXArithmetic.ShiftOp;
import com.oracle.graal.lir.ptx.PTXArithmetic.Unary1Op;
import com.oracle.graal.lir.ptx.PTXArithmetic.Unary2Op;
import com.oracle.graal.lir.ptx.PTXCompare.CompareOp;
import com.oracle.graal.lir.ptx.PTXControlFlow.BranchOp;
import com.oracle.graal.lir.ptx.PTXControlFlow.ReturnOp;
import com.oracle.graal.lir.ptx.PTXControlFlow.ReturnNoValOp;
import com.oracle.graal.lir.ptx.PTXControlFlow.SequentialSwitchOp;
import com.oracle.graal.lir.ptx.PTXControlFlow.TableSwitchOp;
import com.oracle.graal.lir.ptx.PTXMove.MoveFromRegOp;
import com.oracle.graal.lir.ptx.PTXMove.MoveToRegOp;
import com.oracle.graal.lir.ptx.PTXMemOp.LoadOp;
import com.oracle.graal.lir.ptx.PTXMemOp.StoreOp;
import com.oracle.graal.lir.ptx.PTXMemOp.LoadParamOp;
import com.oracle.graal.lir.ptx.PTXMemOp.LoadReturnAddrOp;
import com.oracle.graal.lir.ptx.PTXMemOp.StoreReturnValOp;
import com.oracle.graal.nodes.*;
import com.oracle.graal.nodes.calc.*;
import com.oracle.graal.nodes.calc.ConvertNode.Op;
import com.oracle.graal.nodes.java.*;

/**
 * This class implements the PTX specific portion of the LIR generator.
 */
public class PTXLIRGenerator extends LIRGenerator {

    // Number of the predicate register that can be used when needed.
    // This value will be recorded and incremented in the LIR instruction
    // that sets a predicate register. (e.g., CompareOp)
    private int nextPredRegNum;

    public static final ForeignCallDescriptor ARITHMETIC_FREM = new ForeignCallDescriptor("arithmeticFrem", float.class, float.class, float.class);
    public static final ForeignCallDescriptor ARITHMETIC_DREM = new ForeignCallDescriptor("arithmeticDrem", double.class, double.class, double.class);

    public static class PTXSpillMoveFactory implements LIR.SpillMoveFactory {

        @Override
        public LIRInstruction createMove(AllocatableValue result, Value input) {
            throw GraalInternalError.unimplemented("PTXSpillMoveFactory.createMove()");
        }
    }

    public PTXLIRGenerator(StructuredGraph graph, CodeCacheProvider runtime, TargetDescription target, FrameMap frameMap, CallingConvention cc, LIR lir) {
        super(graph, runtime, target, frameMap, cc, lir);
        lir.spillMoveFactory = new PTXSpillMoveFactory();
        int callVariables = cc.getArgumentCount() + (cc.getReturn() == Value.ILLEGAL ? 0 : 1);
        lir.setFirstVariableNumber(callVariables);
        nextPredRegNum = 0;
    }

    public int getNextPredRegNumber() {
        return nextPredRegNum;
    }

    @Override
    public boolean canStoreConstant(Constant c) {
        // Operand b must be in the .reg state space.
        return false;
    }

    @Override
    public boolean canInlineConstant(Constant c) {
        switch (c.getKind()) {
            case Long:
                return NumUtil.isInt(c.asLong()) && !runtime.needsDataPatch(c);
            case Object:
                return c.isNull();
            default:
                return true;
        }
    }

    protected static AllocatableValue toParamKind(AllocatableValue value) {
        if (value.getKind().getStackKind() != value.getKind()) {
            // We only have stack-kinds in the LIR, so convert the operand kind for values from the
            // calling convention.
            if (isRegister(value)) {
                return asRegister(value).asValue(value.getKind().getStackKind());
            } else if (isStackSlot(value)) {
                return StackSlot.get(value.getKind().getStackKind(), asStackSlot(value).getRawOffset(), asStackSlot(value).getRawAddFrameSize());
            } else {
                throw GraalInternalError.shouldNotReachHere();
            }
        }
        return value;
    }

    @Override
    public void emitPrologue() {
        // Need to emit .param directives based on incoming arguments and return value
        CallingConvention incomingArguments = cc;
        int argCount = incomingArguments.getArgumentCount();
        // Additional argument for return value.
        Variable[] params = new Variable[argCount + 1];
        for (int i = 0; i < argCount; i++) {
            params[i] = (Variable) incomingArguments.getArgument(i);
        }
        // Add the return value as the last parameter.
        params[argCount] = (Variable) incomingArguments.getReturn();

        append(new PTXParameterOp(params));
        for (LocalNode local : graph.getNodes(LocalNode.class)) {
            Value param = params[local.index()];
            setResult(local, emitLoadParam(param.getKind(), param, null));
        }
    }

    @Override
    public Variable emitMove(Value input) {
        Variable result = newVariable(input.getKind());
        emitMove(result, input);
        return result;
    }

    @Override
    public void emitMove(AllocatableValue dst, Value src) {
        if (isRegister(src) || isStackSlot(dst)) {
            append(new MoveFromRegOp(dst, src));
        } else {
            append(new MoveToRegOp(dst, src));
        }
    }

    @Override
    public PTXAddressValue emitAddress(Value base, long displacement, Value index, int scale) {
        AllocatableValue baseRegister;
        long finalDisp = displacement;
        if (isConstant(base)) {
            if (asConstant(base).isNull()) {
                baseRegister = Value.ILLEGAL;
            } else if (asConstant(base).getKind() != Kind.Object) {
                finalDisp += asConstant(base).asLong();
                baseRegister = Value.ILLEGAL;
            } else {
                baseRegister = load(base);
            }
        } else {
            baseRegister = asAllocatable(base);
        }

        @SuppressWarnings("unused")
        Value indexRegister;
        if (!index.equals(Value.ILLEGAL) && scale != 0) {
            if (isConstant(index)) {
                finalDisp += asConstant(index).asLong() * scale;
                indexRegister = Value.ILLEGAL;
            } else {
                if (scale != 1) {
                    Variable longIndex = emitConvert(Op.I2L, index);
                    if (CodeUtil.isPowerOf2(scale)) {
                        indexRegister = emitShl(longIndex, Constant.forLong(CodeUtil.log2(scale)));
                    } else {
                        indexRegister = emitMul(longIndex, Constant.forLong(scale));
                    }
                } else {
                    indexRegister = asAllocatable(index);
                }
            }
        } else {
            indexRegister = Value.ILLEGAL;
        }

        return new PTXAddressValue(target().wordKind, baseRegister, finalDisp);
    }

    private PTXAddressValue asAddress(Value address) {
        assert address != null;

        if (address instanceof PTXAddressValue) {
            return (PTXAddressValue) address;
        } else {
            return emitAddress(address, 0, Value.ILLEGAL, 0);
        }
    }

    @Override
    public Variable emitLoad(Kind kind, Value address, DeoptimizingNode deopting) {
        PTXAddressValue loadAddress = asAddress(address);
        Variable result = newVariable(kind);
        append(new LoadOp(kind, result, loadAddress, deopting != null ? state(deopting) : null));
        return result;
    }

    @Override
    public void emitStore(Kind kind, Value address, Value inputVal, DeoptimizingNode deopting) {
        PTXAddressValue storeAddress = asAddress(address);
        Variable input = load(inputVal);
        append(new StoreOp(kind, storeAddress, input, deopting != null ? state(deopting) : null));
    }

    @Override
    public Variable emitAddress(StackSlot address) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitAddress()");
    }

    @Override
    public void emitJump(LabelRef label) {
        append(new JumpOp(label));
    }

    @Override
    public void emitCompareBranch(Value left, Value right, Condition cond, boolean unorderedIsTrue, LabelRef label) {
        switch (left.getKind().getStackKind()) {
            case Int:
                append(new CompareOp(ICMP, cond, left, right, nextPredRegNum));
                append(new BranchOp(cond, label, nextPredRegNum++));
                break;
            case Long:
                append(new CompareOp(LCMP, cond, left, right, nextPredRegNum));
                append(new BranchOp(cond, label, nextPredRegNum++));
                break;
            case Float:
                append(new CompareOp(FCMP, cond, left, right, nextPredRegNum));
                append(new BranchOp(cond, label, nextPredRegNum++));
                break;
            case Double:
                append(new CompareOp(DCMP, cond, left, right, nextPredRegNum));
                append(new BranchOp(cond, label, nextPredRegNum++));
                break;
            case Object:
                append(new CompareOp(ACMP, cond, left, right, nextPredRegNum));
                append(new BranchOp(cond, label, nextPredRegNum++));
                break;
            default:
                throw GraalInternalError.shouldNotReachHere("" + left.getKind());
        }
    }

    @Override
    public void emitOverflowCheckBranch(LabelRef label, boolean negated) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitOverflowCheckBranch()");
    }

    @Override
    public void emitIntegerTestBranch(Value left, Value right, boolean negated, LabelRef label) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitIntegerTestBranch()");
    }

    @Override
    public Variable emitConditionalMove(Value left, Value right, Condition cond, boolean unorderedIsTrue, Value trueValue, Value falseValue) {
        // TODO: There is no conventional conditional move instruction in PTX.
        // So, this method is changed to throw NYI exception.
        // To be revisited if this needs to be really implemented.
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitConditionalMove()");
    }

    @Override
    public Variable emitIntegerTestMove(Value left, Value right, Value trueValue, Value falseValue) {
        throw new InternalError("NYI");
    }

    @Override
    public Variable emitNegate(Value input) {
        Variable result = newVariable(input.getKind());
        switch (input.getKind()) {
            case Int:
                append(new Op1Stack(INEG, result, input));
                break;
            case Float:
                append(new Op1Stack(FNEG, result, input));
                break;
            case Double:
                append(new Op1Stack(DNEG, result, input));
                break;
            default:
                throw GraalInternalError.shouldNotReachHere();
        }
        return result;
    }

    @Override
    public Variable emitNot(Value input) {
        Variable result = newVariable(input.getKind());
        switch (input.getKind()) {
            case Int:
                append(new Op1Stack(INOT, result, input));
                break;
            case Long:
                append(new Op1Stack(LNOT, result, input));
                break;
            default:
                throw GraalInternalError.shouldNotReachHere();
        }
        return result;
    }

    @Override
    public Variable emitAdd(Value a, Value b) {
        Variable result = newVariable(a.getKind());
        switch (a.getKind()) {
            case Int:
                append(new Op2Stack(IADD, result, a, loadNonConst(b)));
                break;
            case Long:
                append(new Op2Stack(LADD, result, a, loadNonConst(b)));
                break;
            case Float:
                append(new Op2Stack(FADD, result, a, loadNonConst(b)));
                break;
            case Double:
                append(new Op2Stack(DADD, result, a, loadNonConst(b)));
                break;
            default:
                throw GraalInternalError.shouldNotReachHere("missing: " + a.getKind() + " prim: " + a.getKind().isPrimitive());
        }
        return result;
    }

    @Override
    public Variable emitSub(Value a, Value b) {
        Variable result = newVariable(a.getKind());
        switch (a.getKind()) {
            case Int:
                append(new Op2Stack(ISUB, result, a, loadNonConst(b)));
                break;
            case Long:
                append(new Op2Stack(LSUB, result, a, loadNonConst(b)));
                break;
            case Float:
                append(new Op2Stack(FSUB, result, a, loadNonConst(b)));
                break;
            case Double:
                append(new Op2Stack(DSUB, result, a, loadNonConst(b)));
                break;
            default:
                throw GraalInternalError.shouldNotReachHere("missing: " + a.getKind());
        }
        return result;
    }

    @Override
    public Variable emitMul(Value a, Value b) {
        Variable result = newVariable(a.getKind());
        switch (a.getKind()) {
            case Int:
                append(new Op2Reg(IMUL, result, a, loadNonConst(b)));
                break;
            case Long:
                append(new Op2Reg(LMUL, result, a, loadNonConst(b)));
                break;
            case Float:
                append(new Op2Stack(FMUL, result, a, loadNonConst(b)));
                break;
            case Double:
                append(new Op2Stack(DMUL, result, a, loadNonConst(b)));
                break;
            default:
                throw GraalInternalError.shouldNotReachHere("missing: " + a.getKind());
        }
        return result;
    }

    @Override
    protected boolean peephole(ValueNode valueNode) {
        // No peephole optimizations for now
        return false;
    }

    @Override
    public Value emitDiv(Value a, Value b, DeoptimizingNode deopting) {
        Variable result = newVariable(a.getKind());
        switch (a.getKind()) {
            case Int:
                append(new Op2Reg(IDIV, result, a, loadNonConst(b)));
                break;
            case Long:
                append(new Op2Reg(LDIV, result, a, loadNonConst(b)));
                break;
            case Float:
                append(new Op2Stack(FDIV, result, a, loadNonConst(b)));
                break;
            case Double:
                append(new Op2Stack(DDIV, result, a, loadNonConst(b)));
                break;
            default:
                throw GraalInternalError.shouldNotReachHere("missing: " + a.getKind());
        }
        return result;
    }

    @Override
    public Value emitRem(Value a, Value b, DeoptimizingNode deopting) {
        Variable result = newVariable(a.getKind());
        switch (a.getKind()) {
            case Int:
                append(new Op2Reg(IREM, result, a, loadNonConst(b)));
                break;
            case Long:
                append(new Op2Reg(LREM, result, a, loadNonConst(b)));
                break;
            default:
                throw GraalInternalError.shouldNotReachHere("missing: " + a.getKind());
        }
        return result;
    }

    @Override
    public Variable emitUDiv(Value a, Value b, DeoptimizingNode deopting) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitUDiv()");
    }

    @Override
    public Variable emitURem(Value a, Value b, DeoptimizingNode deopting) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitURem()");
    }

    @Override
    public Variable emitAnd(Value a, Value b) {
        Variable result = newVariable(a.getKind());
        switch (a.getKind()) {
            case Int:
                append(new Op2Stack(IAND, result, a, loadNonConst(b)));
                break;
            case Long:
                append(new Op2Stack(LAND, result, a, loadNonConst(b)));
                break;

            default:
                throw GraalInternalError.shouldNotReachHere("missing: " + a.getKind());
        }
        return result;
    }

    @Override
    public Variable emitOr(Value a, Value b) {
        Variable result = newVariable(a.getKind());
        switch (a.getKind()) {
            case Int:
                append(new Op2Stack(IOR, result, a, loadNonConst(b)));
                break;
            case Long:
                append(new Op2Stack(LOR, result, a, loadNonConst(b)));
                break;
            default:
                throw GraalInternalError.shouldNotReachHere("missing: " + a.getKind());
        }
        return result;
    }

    @Override
    public Variable emitXor(Value a, Value b) {
        Variable result = newVariable(a.getKind());
        switch (a.getKind()) {
            case Int:
                append(new Op2Stack(IXOR, result, a, loadNonConst(b)));
                break;
            case Long:
                append(new Op2Stack(LXOR, result, a, loadNonConst(b)));
                break;
            default:
                throw GraalInternalError.shouldNotReachHere();
        }
        return result;
    }

    @Override
    public Variable emitShl(Value a, Value b) {
        Variable result = newVariable(a.getKind());
        switch (a.getKind()) {
            case Int:
                append(new Op2Stack(ISHL, result, a, loadNonConst(b)));
                break;
            case Long:
                append(new Op1Stack(LSHL, result, loadNonConst(b)));
                break;
            default:
                throw GraalInternalError.shouldNotReachHere();
        }
        return result;
    }

    @Override
    public Variable emitShr(Value a, Value b) {
        Variable result = newVariable(a.getKind());
        switch (a.getKind()) {
            case Int:
                append(new Op2Stack(ISHR, result, a, loadNonConst(b)));
                break;
            case Long:
                append(new Op1Stack(LSHR, result, loadNonConst(b)));
                break;
            default:
                throw GraalInternalError.shouldNotReachHere();
        }
        return result;
    }

    @Override
    public Variable emitUShr(Value a, Value b) {
        Variable result = newVariable(a.getKind());
        switch (a.getKind()) {
            case Int:
                append(new ShiftOp(IUSHR, result, a, b));
                break;
            case Long:
                append(new ShiftOp(LUSHR, result, a, b));
                break;
            default:
                throw GraalInternalError.shouldNotReachHere();
        }
        return result;
    }

    @Override
    public Variable emitConvert(ConvertNode.Op opcode, Value inputVal) {
        Variable input = load(inputVal);
        Variable result = newVariable(opcode.to);
        switch (opcode) {
            case I2L:
                append(new Unary2Op(I2L, result, input));
                break;
            case L2I:
                append(new Unary1Op(L2I, result, input));
                break;
            case I2B:
                append(new Unary2Op(I2B, result, input));
                break;
            case I2C:
                append(new Unary1Op(I2C, result, input));
                break;
            case I2S:
                append(new Unary2Op(I2S, result, input));
                break;
            case F2D:
                append(new Unary2Op(F2D, result, input));
                break;
            case D2F:
                append(new Unary2Op(D2F, result, input));
                break;
            case I2F:
                append(new Unary2Op(I2F, result, input));
                break;
            case I2D:
                append(new Unary2Op(I2D, result, input));
                break;
            case F2I:
                append(new Unary2Op(F2I, result, input));
                break;
            case D2I:
                append(new Unary2Op(D2I, result, input));
                break;
            case L2F:
                append(new Unary2Op(L2F, result, input));
                break;
            case L2D:
                append(new Unary2Op(L2D, result, input));
                break;
            case F2L:
                append(new Unary2Op(F2L, result, input));
                break;
            case D2L:
                append(new Unary2Op(D2L, result, input));
                break;
            case MOV_I2F:
                append(new Unary2Op(MOV_I2F, result, input));
                break;
            case MOV_L2D:
                append(new Unary2Op(MOV_L2D, result, input));
                break;
            case MOV_F2I:
                append(new Unary2Op(MOV_F2I, result, input));
                break;
            case MOV_D2L:
                append(new Unary2Op(MOV_D2L, result, input));
                break;
            case UNSIGNED_I2L:
                // Instructions that move or generate 32-bit register values also set the upper 32
                // bits of the register to zero.
                // Consequently, there is no need for a special zero-extension move.
                emitMove(result, input);
                break;
            default:
                throw GraalInternalError.shouldNotReachHere();
        }
        return result;
    }

    @Override
    public void emitDeoptimize(DeoptimizationAction action, DeoptimizationReason reason, DeoptimizingNode deopting) {
        append(new ReturnOp(Value.ILLEGAL));
    }

    @Override
    public void emitMembar(int barriers) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitMembar()");
    }

    @Override
    protected void emitDirectCall(DirectCallTargetNode callTarget, Value result, Value[] parameters, Value[] temps, LIRFrameState callState) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitDirectCall()");
    }

    @Override
    protected void emitIndirectCall(IndirectCallTargetNode callTarget, Value result, Value[] parameters, Value[] temps, LIRFrameState callState) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitIndirectCall()");
    }

    @Override
    protected void emitForeignCall(ForeignCallLinkage callTarget, Value result, Value[] arguments, Value[] temps, LIRFrameState info) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitForeignCall()");
    }

    @Override
    public void emitBitCount(Variable result, Value value) {
        if (value.getKind().getStackKind() == Kind.Int) {
            append(new PTXBitManipulationOp(IPOPCNT, result, value));
        } else {
            append(new PTXBitManipulationOp(LPOPCNT, result, value));
        }
    }

    @Override
    public void emitBitScanForward(Variable result, Value value) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitBitScanForward()");
    }

    @Override
    public void emitBitScanReverse(Variable result, Value value) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitBitScanReverse()");
    }

    @Override
    public Value emitMathAbs(Value input) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitMathAbs()");
    }

    @Override
    public Value emitMathSqrt(Value input) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitMathSqrt()");
    }

    @Override
    public Value emitMathLog(Value input, boolean base10) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitMathLog()");
    }

    @Override
    public Value emitMathCos(Value input) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitMathCos()");
    }

    @Override
    public Value emitMathSin(Value input) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitMathSin()");
    }

    @Override
    public Value emitMathTan(Value input) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitMathTan()");
    }

    @Override
    public void emitByteSwap(Variable result, Value input) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitByteSwap()");
    }

    @Override
    protected void emitReturn(Value input) {
        append(new ReturnOp(input));
    }

    private void emitReturnNoVal() {
        append(new ReturnNoValOp());
    }

    @Override
    protected void emitSequentialSwitch(Constant[] keyConstants, LabelRef[] keyTargets, LabelRef defaultTarget, Value key) {
        // Making a copy of the switch value is necessary because jump table destroys the input
        // value
        if (key.getKind() == Kind.Int || key.getKind() == Kind.Long) {
            append(new SequentialSwitchOp(keyConstants, keyTargets, defaultTarget, key, Value.ILLEGAL, nextPredRegNum));
        } else {
            assert key.getKind() == Kind.Object : key.getKind();
            append(new SequentialSwitchOp(keyConstants, keyTargets, defaultTarget, key, newVariable(Kind.Object), nextPredRegNum));
        }
    }

    @Override
    protected void emitSwitchRanges(int[] lowKeys, int[] highKeys, LabelRef[] targets, LabelRef defaultTarget, Value key) {
        throw new InternalError("NYI");
    }

    @Override
    protected void emitTableSwitch(int lowKey, LabelRef defaultTarget, LabelRef[] targets, Value key) {
        // Making a copy of the switch value is necessary because jump table destroys the input
        // value
        Variable tmp = emitMove(key);
        append(new TableSwitchOp(lowKey, defaultTarget, targets, tmp, newVariable(target.wordKind), nextPredRegNum++));
    }

    @Override
    public void visitCompareAndSwap(LoweredCompareAndSwapNode node, Value address) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.visitCompareAndSwap()");
    }

    @Override
    public void visitBreakpointNode(BreakpointNode node) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.visitBreakpointNode()");
    }

    @Override
    public void visitSafepointNode(SafepointNode i) {
        // LIRFrameState info = state(i);
        // append(new PTXSafepointOp(info, runtime().config, this));
        Debug.log("visitSafePointNode unimplemented");
    }

    @Override
    public void emitUnwind(Value operand) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitUnwind()");
    }

    @Override
    public void emitNullCheck(ValueNode v, DeoptimizingNode deopting) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.emitNullCheck()");
    }

    @Override
    public void visitInfopointNode(InfopointNode i) {
        throw GraalInternalError.unimplemented("PTXLIRGenerator.visitInfopointNode()");
    }

    public Variable emitLoadParam(Kind kind, Value address, DeoptimizingNode deopting) {
        PTXAddressValue loadAddress = asAddress(address);
        Variable result = newVariable(kind);
        append(new LoadParamOp(kind, result, loadAddress, deopting != null ? state(deopting) : null));
        return result;
    }

    public Variable emitLoadReturnAddress(Kind kind, Value address, DeoptimizingNode deopting) {
        PTXAddressValue loadAddress = asAddress(address);
        Variable result = newVariable(kind);
        append(new LoadReturnAddrOp(kind, result, loadAddress, deopting != null ? state(deopting) : null));
        return result;
    }

    public void emitStoreReturnValue(Kind kind, Value address, Value inputVal, DeoptimizingNode deopting) {
        PTXAddressValue storeAddress = asAddress(address);
        Variable input = load(inputVal);
        append(new StoreReturnValOp(kind, storeAddress, input, deopting != null ? state(deopting) : null));
    }

    @Override
    public AllocatableValue resultOperandFor(Kind kind) {
        if (kind == Kind.Void) {
            return ILLEGAL;
        }
        return (new Variable(kind, 0));
    }

    @Override
    public void visitReturn(ReturnNode x) {
        AllocatableValue operand = Value.ILLEGAL;
        if (x.result() != null) {
            operand = resultOperandFor(x.result().kind());
            // Load the global memory address from return parameter
            Variable loadVar = emitLoadReturnAddress(operand.getKind(), operand, null);
            // Store result in global memory whose location is loadVar
            emitStoreReturnValue(operand.getKind(), loadVar, operand(x.result()), null);
        }
        emitReturnNoVal();
    }
}