/*
 * Copyright (c) 2013, 2017, 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
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package org.graalvm.compiler.hotspot.sparc;

import static jdk.vm.ci.sparc.SPARCKind.WORD;
import static jdk.vm.ci.sparc.SPARCKind.XWORD;
import static org.graalvm.compiler.lir.LIRValueUtil.asConstant;
import static org.graalvm.compiler.lir.LIRValueUtil.isConstantValue;

import org.graalvm.compiler.asm.sparc.SPARCAssembler;
import org.graalvm.compiler.core.common.CompressEncoding;
import org.graalvm.compiler.core.common.LIRKind;
import org.graalvm.compiler.core.common.calc.Condition;
import org.graalvm.compiler.core.common.spi.ForeignCallLinkage;
import org.graalvm.compiler.core.common.spi.LIRKindTool;
import org.graalvm.compiler.core.sparc.SPARCArithmeticLIRGenerator;
import org.graalvm.compiler.core.sparc.SPARCLIRGenerator;
import org.graalvm.compiler.core.sparc.SPARCLIRKindTool;
import org.graalvm.compiler.debug.GraalError;
import org.graalvm.compiler.hotspot.GraalHotSpotVMConfig;
import org.graalvm.compiler.hotspot.HotSpotBackend;
import org.graalvm.compiler.hotspot.HotSpotDebugInfoBuilder;
import org.graalvm.compiler.hotspot.HotSpotForeignCallLinkage;
import org.graalvm.compiler.hotspot.HotSpotLIRGenerationResult;
import org.graalvm.compiler.hotspot.HotSpotLIRGenerator;
import org.graalvm.compiler.hotspot.HotSpotLockStack;
import org.graalvm.compiler.hotspot.debug.BenchmarkCounters;
import org.graalvm.compiler.hotspot.meta.HotSpotProviders;
import org.graalvm.compiler.hotspot.meta.HotSpotRegistersProvider;
import org.graalvm.compiler.hotspot.stubs.Stub;
import org.graalvm.compiler.lir.LIRFrameState;
import org.graalvm.compiler.lir.LIRInstruction;
import org.graalvm.compiler.lir.LabelRef;
import org.graalvm.compiler.lir.StandardOp.SaveRegistersOp;
import org.graalvm.compiler.lir.SwitchStrategy;
import org.graalvm.compiler.lir.Variable;
import org.graalvm.compiler.lir.VirtualStackSlot;
import org.graalvm.compiler.lir.gen.LIRGenerationResult;
import org.graalvm.compiler.lir.sparc.SPARCAddressValue;
import org.graalvm.compiler.lir.sparc.SPARCControlFlow.StrategySwitchOp;
import org.graalvm.compiler.lir.sparc.SPARCFrameMapBuilder;
import org.graalvm.compiler.lir.sparc.SPARCImmediateAddressValue;
import org.graalvm.compiler.lir.sparc.SPARCMove.CompareAndSwapOp;
import org.graalvm.compiler.lir.sparc.SPARCMove.NullCheckOp;
import org.graalvm.compiler.lir.sparc.SPARCMove.StoreOp;
import org.graalvm.compiler.lir.sparc.SPARCPrefetchOp;
import org.graalvm.compiler.lir.sparc.SPARCSaveRegistersOp;

import jdk.vm.ci.code.CallingConvention;
import jdk.vm.ci.code.Register;
import jdk.vm.ci.code.RegisterValue;
import jdk.vm.ci.code.StackSlot;
import jdk.vm.ci.hotspot.HotSpotCompressedNullConstant;
import jdk.vm.ci.hotspot.HotSpotObjectConstant;
import jdk.vm.ci.meta.AllocatableValue;
import jdk.vm.ci.meta.Constant;
import jdk.vm.ci.meta.DeoptimizationAction;
import jdk.vm.ci.meta.DeoptimizationReason;
import jdk.vm.ci.meta.JavaConstant;
import jdk.vm.ci.meta.JavaKind;
import jdk.vm.ci.meta.PlatformKind;
import jdk.vm.ci.meta.Value;
import jdk.vm.ci.meta.ValueKind;
import jdk.vm.ci.sparc.SPARC;
import jdk.vm.ci.sparc.SPARCKind;

public class SPARCHotSpotLIRGenerator extends SPARCLIRGenerator implements HotSpotLIRGenerator {

    final GraalHotSpotVMConfig config;
    private HotSpotDebugInfoBuilder debugInfoBuilder;

    public SPARCHotSpotLIRGenerator(HotSpotProviders providers, GraalHotSpotVMConfig config, LIRGenerationResult lirGenRes) {
        this(providers, config, lirGenRes, new ConstantTableBaseProvider());
    }

    private SPARCHotSpotLIRGenerator(HotSpotProviders providers, GraalHotSpotVMConfig config, LIRGenerationResult lirGenRes, ConstantTableBaseProvider constantTableBaseProvider) {
        this(new SPARCLIRKindTool(), new SPARCArithmeticLIRGenerator(), new SPARCHotSpotMoveFactory(constantTableBaseProvider), providers, config, lirGenRes, constantTableBaseProvider);
    }

    public SPARCHotSpotLIRGenerator(LIRKindTool lirKindTool, SPARCArithmeticLIRGenerator arithmeticLIRGen, MoveFactory moveFactory, HotSpotProviders providers, GraalHotSpotVMConfig config,
                    LIRGenerationResult lirGenRes, ConstantTableBaseProvider constantTableBaseProvider) {
        super(lirKindTool, arithmeticLIRGen, moveFactory, providers, lirGenRes, constantTableBaseProvider);
        assert config.basicLockSize == 8;
        this.config = config;
    }

    @Override
    public HotSpotProviders getProviders() {
        return (HotSpotProviders) super.getProviders();
    }

    /**
     * The slot reserved for storing the original return address when a frame is marked for
     * deoptimization. The return address slot in the callee is overwritten with the address of a
     * deoptimization stub.
     */
    private StackSlot deoptimizationRescueSlot;

    /**
     * Value where the address for safepoint poll is kept.
     */
    private AllocatableValue safepointAddressValue;

    @Override
    public VirtualStackSlot getLockSlot(int lockDepth) {
        return getLockStack().makeLockSlot(lockDepth);
    }

    private HotSpotLockStack getLockStack() {
        assert debugInfoBuilder != null && debugInfoBuilder.lockStack() != null;
        return debugInfoBuilder.lockStack();
    }

    @Override
    public boolean needOnlyOopMaps() {
        // Stubs only need oop maps
        return getStub() != null;
    }

    public Stub getStub() {
        return getResult().getStub();
    }

    @Override
    public HotSpotLIRGenerationResult getResult() {
        return ((HotSpotLIRGenerationResult) super.getResult());
    }

    @Override
    public void beforeRegisterAllocation() {
        super.beforeRegisterAllocation();
        boolean hasDebugInfo = getResult().getLIR().hasDebugInfo();
        if (hasDebugInfo) {
            getResult().setDeoptimizationRescueSlot(((SPARCFrameMapBuilder) getResult().getFrameMapBuilder()).allocateDeoptimizationRescueSlot());
        }

        getResult().setMaxInterpreterFrameSize(debugInfoBuilder.maxInterpreterFrameSize());
    }

    @Override
    public Variable emitForeignCall(ForeignCallLinkage linkage, LIRFrameState state, Value... args) {
        HotSpotForeignCallLinkage hotspotLinkage = (HotSpotForeignCallLinkage) linkage;
        Variable result;
        LIRFrameState debugInfo = null;
        if (hotspotLinkage.needsDebugInfo()) {
            debugInfo = state;
            assert debugInfo != null || getStub() != null;
        }

        if (linkage.destroysRegisters() || hotspotLinkage.needsJavaFrameAnchor()) {
            HotSpotRegistersProvider registers = getProviders().getRegisters();
            Register thread = registers.getThreadRegister();
            Value threadTemp = newVariable(LIRKind.value(SPARCKind.XWORD));
            Register stackPointer = registers.getStackPointerRegister();
            Variable spScratch = newVariable(LIRKind.value(target().arch.getWordKind()));
            append(new SPARCHotSpotCRuntimeCallPrologueOp(config.threadLastJavaSpOffset(), thread, stackPointer, threadTemp, spScratch));
            result = super.emitForeignCall(hotspotLinkage, debugInfo, args);
            append(new SPARCHotSpotCRuntimeCallEpilogueOp(config.threadLastJavaSpOffset(), config.threadLastJavaPcOffset(), config.threadJavaFrameAnchorFlagsOffset(), thread, threadTemp));
        } else {
            result = super.emitForeignCall(hotspotLinkage, debugInfo, args);
        }

        return result;
    }

    @Override
    public void emitReturn(JavaKind javaKind, Value input) {
        AllocatableValue operand = Value.ILLEGAL;
        if (input != null) {
            operand = resultOperandFor(javaKind, input.getValueKind());
            emitMove(operand, input);
        }
        append(new SPARCHotSpotReturnOp(operand, getStub() != null, config, getSafepointAddressValue()));
    }

    @Override
    public void emitTailcall(Value[] args, Value address) {
        throw GraalError.unimplemented();
    }

    @Override
    public void emitUnwind(Value exception) {
        ForeignCallLinkage linkage = getForeignCalls().lookupForeignCall(HotSpotBackend.UNWIND_EXCEPTION_TO_CALLER);
        CallingConvention linkageCc = linkage.getOutgoingCallingConvention();
        assert linkageCc.getArgumentCount() == 2;
        RegisterValue exceptionParameter = (RegisterValue) linkageCc.getArgument(0);
        emitMove(exceptionParameter, exception);
        append(new SPARCHotSpotUnwindOp(exceptionParameter));
    }

    private void moveDeoptValuesToThread(Value actionAndReason, Value speculation) {
        moveValueToThread(actionAndReason, config.pendingDeoptimizationOffset);
        moveValueToThread(speculation, config.pendingFailedSpeculationOffset);
    }

    private void moveValueToThread(Value v, int offset) {
        LIRKind wordKind = LIRKind.value(target().arch.getWordKind());
        RegisterValue thread = getProviders().getRegisters().getThreadRegister().asValue(wordKind);
        SPARCAddressValue pendingDeoptAddress = new SPARCImmediateAddressValue(wordKind, thread, offset);
        append(new StoreOp(v.getPlatformKind(), pendingDeoptAddress, load(v), null));
    }

    @Override
    public void emitDeoptimize(Value actionAndReason, Value speculation, LIRFrameState state) {
        moveDeoptValuesToThread(actionAndReason, speculation);
        append(new SPARCDeoptimizeOp(state, target().arch.getWordKind()));
    }

    @Override
    public void emitDeoptimizeCaller(DeoptimizationAction action, DeoptimizationReason reason) {
        Value actionAndReason = emitJavaConstant(getMetaAccess().encodeDeoptActionAndReason(action, reason, 0));
        Value nullValue = emitJavaConstant(JavaConstant.NULL_POINTER);
        moveDeoptValuesToThread(actionAndReason, nullValue);
        append(new SPARCHotSpotDeoptimizeCallerOp());
    }

    @Override
    public Variable emitLogicCompareAndSwap(Value address, Value expectedValue, Value newValue, Value trueValue, Value falseValue) {
        ValueKind<?> kind = newValue.getValueKind();
        assert kind.equals(expectedValue.getValueKind());
        SPARCKind memKind = (SPARCKind) kind.getPlatformKind();
        Variable result = newVariable(newValue.getValueKind());
        append(new CompareAndSwapOp(result, asAllocatable(address), asAllocatable(expectedValue), asAllocatable(newValue)));
        return emitConditionalMove(memKind, expectedValue, result, Condition.EQ, true, trueValue, falseValue);
    }

    @Override
    public Variable emitValueCompareAndSwap(Value address, Value expectedValue, Value newValue) {
        ValueKind<?> kind = newValue.getValueKind();
        assert kind.equals(expectedValue.getValueKind());
        Variable result = newVariable(newValue.getValueKind());
        append(new CompareAndSwapOp(result, asAllocatable(address), asAllocatable(expectedValue), asAllocatable(newValue)));
        return result;
    }

    @Override
    public void emitPrefetchAllocate(Value address) {
        SPARCAddressValue addr = asAddressValue(address);
        append(new SPARCPrefetchOp(addr, SPARCAssembler.Fcn.SeveralWritesAndPossiblyReads));
    }

    public StackSlot getDeoptimizationRescueSlot() {
        return deoptimizationRescueSlot;
    }

    @Override
    public void emitCompareBranch(PlatformKind cmpKind, Value x, Value y, Condition cond, boolean unorderedIsTrue, LabelRef trueDestination, LabelRef falseDestination,
                    double trueDestinationProbability) {
        Value localX = x;
        Value localY = y;
        if (localX instanceof HotSpotObjectConstant) {
            localX = load(localX);
        }
        if (localY instanceof HotSpotObjectConstant) {
            localY = load(localY);
        }
        super.emitCompareBranch(cmpKind, localX, localY, cond, unorderedIsTrue, trueDestination, falseDestination, trueDestinationProbability);
    }

    @Override
    protected boolean emitCompare(SPARCKind cmpKind, Value a, Value b) {
        Value localA = a;
        Value localB = b;
        if (isConstantValue(a)) {
            Constant c = asConstant(a);
            if (HotSpotCompressedNullConstant.COMPRESSED_NULL.equals(c)) {
                localA = SPARC.g0.asValue(LIRKind.value(WORD));
            } else if (c instanceof HotSpotObjectConstant) {
                localA = load(localA);
            }
        }
        if (isConstantValue(b)) {
            Constant c = asConstant(b);
            if (HotSpotCompressedNullConstant.COMPRESSED_NULL.equals(c)) {
                localB = SPARC.g0.asValue(LIRKind.value(WORD));
            } else if (c instanceof HotSpotObjectConstant) {
                localB = load(localB);
            }
        }
        return super.emitCompare(cmpKind, localA, localB);
    }

    @Override
    public Value emitCompress(Value pointer, CompressEncoding encoding, boolean nonNull) {
        LIRKind inputKind = pointer.getValueKind(LIRKind.class);
        assert inputKind.getPlatformKind() == XWORD : inputKind;
        if (inputKind.isReference(0)) {
            // oop
            Variable result = newVariable(LIRKind.reference(WORD));
            append(new SPARCHotSpotMove.CompressPointer(result, asAllocatable(pointer), getProviders().getRegisters().getHeapBaseRegister().asValue(), encoding, nonNull));
            return result;
        } else {
            // metaspace pointer
            Variable result = newVariable(LIRKind.value(WORD));
            AllocatableValue base = Value.ILLEGAL;
            if (encoding.hasBase()) {
                base = emitLoadConstant(LIRKind.value(XWORD), JavaConstant.forLong(encoding.getBase()));
            }
            append(new SPARCHotSpotMove.CompressPointer(result, asAllocatable(pointer), base, encoding, nonNull));
            return result;
        }
    }

    @Override
    public Value emitUncompress(Value pointer, CompressEncoding encoding, boolean nonNull) {
        LIRKind inputKind = pointer.getValueKind(LIRKind.class);
        assert inputKind.getPlatformKind() == WORD;
        if (inputKind.isReference(0)) {
            // oop
            Variable result = newVariable(LIRKind.reference(XWORD));
            append(new SPARCHotSpotMove.UncompressPointer(result, asAllocatable(pointer), getProviders().getRegisters().getHeapBaseRegister().asValue(), encoding, nonNull));
            return result;
        } else {
            // metaspace pointer
            Variable result = newVariable(LIRKind.value(XWORD));
            AllocatableValue base = Value.ILLEGAL;
            if (encoding.hasBase()) {
                base = emitLoadConstant(LIRKind.value(XWORD), JavaConstant.forLong(encoding.getBase()));
            }
            append(new SPARCHotSpotMove.UncompressPointer(result, asAllocatable(pointer), base, encoding, nonNull));
            return result;
        }
    }

    /**
     * @param savedRegisters the registers saved by this operation which may be subject to pruning
     * @param savedRegisterLocations the slots to which the registers are saved
     * @param supportsRemove determines if registers can be pruned
     */
    protected SPARCSaveRegistersOp emitSaveRegisters(Register[] savedRegisters, AllocatableValue[] savedRegisterLocations, boolean supportsRemove) {
        SPARCSaveRegistersOp save = new SPARCSaveRegistersOp(savedRegisters, savedRegisterLocations, supportsRemove);
        append(save);
        return save;
    }

    @Override
    public void emitNullCheck(Value address, LIRFrameState state) {
        PlatformKind kind = address.getPlatformKind();
        if (kind == WORD) {
            CompressEncoding encoding = config.getOopEncoding();
            Value uncompressed = emitUncompress(address, encoding, false);
            append(new NullCheckOp(asAddressValue(uncompressed), state));
        } else {
            super.emitNullCheck(address, state);
        }
    }

    @Override
    public LIRInstruction createBenchmarkCounter(String name, String group, Value increment) {
        if (BenchmarkCounters.enabled) {
            return new SPARCHotSpotCounterOp(name, group, increment, getProviders().getRegisters(), config);
        }
        throw GraalError.shouldNotReachHere("BenchmarkCounters are not enabled!");
    }

    @Override
    public LIRInstruction createMultiBenchmarkCounter(String[] names, String[] groups, Value[] increments) {
        if (BenchmarkCounters.enabled) {
            return new SPARCHotSpotCounterOp(names, groups, increments, getProviders().getRegisters(), config);
        }
        throw GraalError.shouldNotReachHere("BenchmarkCounters are not enabled!");
    }

    public AllocatableValue getSafepointAddressValue() {
        if (this.safepointAddressValue == null) {
            this.safepointAddressValue = newVariable(LIRKind.value(target().arch.getWordKind()));
        }
        return this.safepointAddressValue;
    }

    @Override
    protected StrategySwitchOp createStrategySwitchOp(AllocatableValue base, SwitchStrategy strategy, LabelRef[] keyTargets, LabelRef defaultTarget, Variable key, Variable scratchValue) {
        return new SPARCHotSpotStrategySwitchOp(base, strategy, keyTargets, defaultTarget, key, scratchValue);
    }

    public void setDebugInfoBuilder(HotSpotDebugInfoBuilder debugInfoBuilder) {
        this.debugInfoBuilder = debugInfoBuilder;
    }

    @Override
    public SaveRegistersOp createZapRegisters(Register[] zappedRegisters, JavaConstant[] zapValues) {
        throw GraalError.unimplemented();
    }

    @Override
    public LIRInstruction createZapArgumentSpace(StackSlot[] zappedStack, JavaConstant[] zapValues) {
        throw GraalError.unimplemented();
    }
}