/*

 * Copyright (c) 2015, 2019, 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

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package org.graalvm.compiler.hotspot;

import static org.graalvm.compiler.core.common.GraalOptions.OptAssumptions;

import java.io.ByteArrayOutputStream;

import java.io.PrintStream;

import java.util.Collections;

import java.util.Formattable;

import java.util.Formatter;

import java.util.List;

import org.graalvm.compiler.api.runtime.GraalJVMCICompiler;

import org.graalvm.compiler.code.CompilationResult;

import org.graalvm.compiler.core.GraalCompiler;

import org.graalvm.compiler.core.common.CompilationIdentifier;

import org.graalvm.compiler.core.common.util.CompilationAlarm;

import org.graalvm.compiler.debug.DebugContext;

import org.graalvm.compiler.debug.DebugContext.Activation;

import org.graalvm.compiler.debug.DebugHandlersFactory;

import org.graalvm.compiler.debug.DebugOptions;

import org.graalvm.compiler.hotspot.CompilationCounters.Options;

import org.graalvm.compiler.hotspot.meta.HotSpotProviders;

import org.graalvm.compiler.hotspot.phases.OnStackReplacementPhase;

import org.graalvm.compiler.java.GraphBuilderPhase;

import org.graalvm.compiler.lir.asm.CompilationResultBuilderFactory;

import org.graalvm.compiler.lir.phases.LIRSuites;

import org.graalvm.compiler.nodes.Cancellable;

import org.graalvm.compiler.nodes.StructuredGraph;

import org.graalvm.compiler.nodes.StructuredGraph.AllowAssumptions;

import org.graalvm.compiler.nodes.graphbuilderconf.GraphBuilderConfiguration;

import org.graalvm.compiler.options.OptionValues;

import org.graalvm.compiler.phases.OptimisticOptimizations;

import org.graalvm.compiler.phases.OptimisticOptimizations.Optimization;

import org.graalvm.compiler.phases.PhaseSuite;

import org.graalvm.compiler.phases.tiers.HighTierContext;

import org.graalvm.compiler.phases.tiers.Suites;

import org.graalvm.compiler.printer.GraalDebugHandlersFactory;

import org.graalvm.compiler.serviceprovider.GraalUnsafeAccess;

import jdk.vm.ci.code.CompilationRequest;

import jdk.vm.ci.code.CompilationRequestResult;

import jdk.vm.ci.hotspot.HotSpotCompilationRequest;

import jdk.vm.ci.hotspot.HotSpotCompilationRequestResult;

import jdk.vm.ci.hotspot.HotSpotJVMCIRuntime;

import jdk.vm.ci.meta.DefaultProfilingInfo;

import jdk.vm.ci.meta.JavaMethod;

import jdk.vm.ci.meta.ProfilingInfo;

import jdk.vm.ci.meta.ResolvedJavaMethod;

import jdk.vm.ci.meta.SpeculationLog;

import jdk.vm.ci.meta.TriState;

import jdk.vm.ci.runtime.JVMCICompiler;

import sun.misc.Unsafe;

public class HotSpotGraalCompiler implements GraalJVMCICompiler, Cancellable {

    private static final Unsafe UNSAFE = GraalUnsafeAccess.getUnsafe();

    private final HotSpotJVMCIRuntime jvmciRuntime;

    private final HotSpotGraalRuntimeProvider graalRuntime;

    private final CompilationCounters compilationCounters;

    private final BootstrapWatchDog bootstrapWatchDog;

    private List<DebugHandlersFactory> factories;

    HotSpotGraalCompiler(HotSpotJVMCIRuntime jvmciRuntime, HotSpotGraalRuntimeProvider graalRuntime, OptionValues options) {

        this.jvmciRuntime = jvmciRuntime;

        this.graalRuntime = graalRuntime;

        // It is sufficient to have one compilation counter object per compiler object.

        this.compilationCounters = Options.CompilationCountLimit.getValue(options) > 0 ? new CompilationCounters(options) : null;

        this.bootstrapWatchDog = graalRuntime.isBootstrapping() && !DebugOptions.BootstrapInitializeOnly.getValue(options) ? BootstrapWatchDog.maybeCreate(graalRuntime) : null;

    }

    public List<DebugHandlersFactory> getDebugHandlersFactories() {

        if (factories == null) {

            factories = Collections.singletonList(new GraalDebugHandlersFactory(graalRuntime.getHostProviders().getSnippetReflection()));

        }

        return factories;

    }

    @Override

    public HotSpotGraalRuntimeProvider getGraalRuntime() {

        return graalRuntime;

    }

    @Override

    public CompilationRequestResult compileMethod(CompilationRequest request) {

        return compileMethod(request, true, graalRuntime.getOptions());

    }

    @SuppressWarnings("try")

    CompilationRequestResult compileMethod(CompilationRequest request, boolean installAsDefault, OptionValues initialOptions) {

        try (CompilationContext scope = HotSpotGraalServices.openLocalCompilationContext(request)) {

            if (graalRuntime.isShutdown()) {

                return HotSpotCompilationRequestResult.failure(String.format("Shutdown entered"), true);

            }

            ResolvedJavaMethod method = request.getMethod();

            if (graalRuntime.isBootstrapping()) {

                if (DebugOptions.BootstrapInitializeOnly.getValue(initialOptions)) {

                    return HotSpotCompilationRequestResult.failure(String.format("Skip compilation because %s is enabled", DebugOptions.BootstrapInitializeOnly.getName()), true);

                }

                if (bootstrapWatchDog != null) {

                    if (bootstrapWatchDog.hitCriticalCompilationRateOrTimeout()) {

                        // Drain the compilation queue to expedite completion of the bootstrap

                        return HotSpotCompilationRequestResult.failure("hit critical bootstrap compilation rate or timeout", true);

                    }

                }

            }

            HotSpotCompilationRequest hsRequest = (HotSpotCompilationRequest) request;

            CompilationTask task = new CompilationTask(jvmciRuntime, this, hsRequest, true, shouldRetainLocalVariables(hsRequest.getJvmciEnv()), installAsDefault);

            OptionValues options = task.filterOptions(initialOptions);

            try (CompilationWatchDog w1 = CompilationWatchDog.watch(method, hsRequest.getId(), options);

                            BootstrapWatchDog.Watch w2 = bootstrapWatchDog == null ? null : bootstrapWatchDog.watch(request);

                            CompilationAlarm alarm = CompilationAlarm.trackCompilationPeriod(options);) {

                if (compilationCounters != null) {

                    compilationCounters.countCompilation(method);

                }

                CompilationRequestResult r = null;

                try (DebugContext debug = graalRuntime.openDebugContext(options, task.getCompilationIdentifier(), method, getDebugHandlersFactories(), DebugContext.DEFAULT_LOG_STREAM);

                                Activation a = debug.activate()) {

                    r = task.runCompilation(debug);

                }

                assert r != null;

                return r;

            }

        }

    }

    private boolean shouldRetainLocalVariables(long envAddress) {

        GraalHotSpotVMConfig config = graalRuntime.getVMConfig();

        if (envAddress == 0) {

            return false;

        }

        if (config.jvmciCompileStateCanPopFrameOffset != Integer.MIN_VALUE) {

            if ((UNSAFE.getByte(envAddress + config.jvmciCompileStateCanPopFrameOffset) & 0xFF) != 0) {

                return true;

            }

        }

        if (config.jvmciCompileStateCanAccessLocalVariablesOffset != Integer.MIN_VALUE) {

            if ((UNSAFE.getByte(envAddress + config.jvmciCompileStateCanAccessLocalVariablesOffset) & 0xFF) != 0) {

                return true;

            }

        }

        return false;

    }

    @Override

    public boolean isCancelled() {

        return graalRuntime.isShutdown();

    }

    public StructuredGraph createGraph(ResolvedJavaMethod method, int entryBCI, boolean useProfilingInfo, CompilationIdentifier compilationId, OptionValues options, DebugContext debug) {

        HotSpotBackend backend = graalRuntime.getHostBackend();

        HotSpotProviders providers = backend.getProviders();

        final boolean isOSR = entryBCI != JVMCICompiler.INVOCATION_ENTRY_BCI;

        StructuredGraph graph = method.isNative() || isOSR ? null : providers.getReplacements().getIntrinsicGraph(method, compilationId, debug, this);

        if (graph == null) {

            SpeculationLog speculationLog = method.getSpeculationLog();

            if (speculationLog != null) {

                speculationLog.collectFailedSpeculations();

            }

            // @formatter:off

            graph = new StructuredGraph.Builder(options, debug, AllowAssumptions.ifTrue(OptAssumptions.getValue(options))).

                            method(method).

                            cancellable(this).

                            entryBCI(entryBCI).

                            speculationLog(speculationLog).

                            useProfilingInfo(useProfilingInfo).

                            compilationId(compilationId).build();

            // @formatter:on

        }

        return graph;

    }

    public CompilationResult compileHelper(CompilationResultBuilderFactory crbf, CompilationResult result, StructuredGraph graph, ResolvedJavaMethod method, int entryBCI, boolean useProfilingInfo,

                    OptionValues options) {

        return compileHelper(crbf, result, graph, method, entryBCI, useProfilingInfo, false, options);

    }

    public CompilationResult compileHelper(CompilationResultBuilderFactory crbf, CompilationResult result, StructuredGraph graph, ResolvedJavaMethod method, int entryBCI, boolean useProfilingInfo,

                    boolean shouldRetainLocalVariables, OptionValues options) {

        assert options == graph.getOptions();

        HotSpotBackend backend = graalRuntime.getHostBackend();

        HotSpotProviders providers = backend.getProviders();

        final boolean isOSR = entryBCI != JVMCICompiler.INVOCATION_ENTRY_BCI;

        Suites suites = getSuites(providers, options);

        LIRSuites lirSuites = getLIRSuites(providers, options);

        ProfilingInfo profilingInfo = useProfilingInfo ? method.getProfilingInfo(!isOSR, isOSR) : DefaultProfilingInfo.get(TriState.FALSE);

        OptimisticOptimizations optimisticOpts = getOptimisticOpts(profilingInfo, options);

        /*

         * Cut off never executed code profiles if there is code, e.g. after the osr loop, that is

         * never executed.

         */

        if (isOSR && !OnStackReplacementPhase.Options.DeoptAfterOSR.getValue(options)) {

            optimisticOpts.remove(Optimization.RemoveNeverExecutedCode);

        }

        result.setEntryBCI(entryBCI);

        boolean shouldDebugNonSafepoints = providers.getCodeCache().shouldDebugNonSafepoints();

        PhaseSuite<HighTierContext> graphBuilderSuite = configGraphBuilderSuite(providers.getSuites().getDefaultGraphBuilderSuite(), shouldDebugNonSafepoints, shouldRetainLocalVariables, isOSR);

        GraalCompiler.compileGraph(graph, method, providers, backend, graphBuilderSuite, optimisticOpts, profilingInfo, suites, lirSuites, result, crbf, true);

        if (!isOSR && useProfilingInfo) {

            ProfilingInfo profile = profilingInfo;

            profile.setCompilerIRSize(StructuredGraph.class, graph.getNodeCount());

        }

        return result;

    }

    public CompilationResult compile(ResolvedJavaMethod method,

                    int entryBCI,

                    boolean useProfilingInfo,

                    boolean shouldRetainLocalVariables,

                    CompilationIdentifier compilationId,

                    DebugContext debug) {

        StructuredGraph graph = createGraph(method, entryBCI, useProfilingInfo, compilationId, debug.getOptions(), debug);

        CompilationResult result = new CompilationResult(compilationId);

        return compileHelper(CompilationResultBuilderFactory.Default, result, graph, method, entryBCI, useProfilingInfo, shouldRetainLocalVariables, debug.getOptions());

    }

    protected OptimisticOptimizations getOptimisticOpts(ProfilingInfo profilingInfo, OptionValues options) {

        return new OptimisticOptimizations(profilingInfo, options);

    }

    protected Suites getSuites(HotSpotProviders providers, OptionValues options) {

        return providers.getSuites().getDefaultSuites(options);

    }

    protected LIRSuites getLIRSuites(HotSpotProviders providers, OptionValues options) {

        return providers.getSuites().getDefaultLIRSuites(options);

    }

    /**

     * Reconfigures a given graph builder suite (GBS) if one of the given GBS parameter values is

     * not the default.

     *

     * @param suite the graph builder suite

     * @param shouldDebugNonSafepoints specifies if extra debug info should be generated (default is

     *            false)

     * @param shouldRetainLocalVariables specifies if local variables should be retained for

     *            debugging purposes (default is false)

     * @param isOSR specifies if extra OSR-specific post-processing is required (default is false)

     * @return a new suite derived from {@code suite} if any of the GBS parameters did not have a

     *         default value otherwise {@code suite}

     */

    protected PhaseSuite<HighTierContext> configGraphBuilderSuite(PhaseSuite<HighTierContext> suite, boolean shouldDebugNonSafepoints, boolean shouldRetainLocalVariables, boolean isOSR) {

        if (shouldDebugNonSafepoints || shouldRetainLocalVariables || isOSR) {

            PhaseSuite<HighTierContext> newGbs = suite.copy();

            GraphBuilderPhase graphBuilderPhase = (GraphBuilderPhase) newGbs.findPhase(GraphBuilderPhase.class).previous();

            GraphBuilderConfiguration graphBuilderConfig = graphBuilderPhase.getGraphBuilderConfig();

            if (shouldDebugNonSafepoints) {

                graphBuilderConfig = graphBuilderConfig.withNodeSourcePosition(true);

            }

            if (shouldRetainLocalVariables) {

                graphBuilderConfig = graphBuilderConfig.withRetainLocalVariables(true);

            }

            GraphBuilderPhase newGraphBuilderPhase = new GraphBuilderPhase(graphBuilderConfig);

            newGbs.findPhase(GraphBuilderPhase.class).set(newGraphBuilderPhase);

            if (isOSR) {

                newGbs.appendPhase(new OnStackReplacementPhase());

            }

            return newGbs;

        }

        return suite;

    }

    /**

     * Converts {@code method} to a String with {@link JavaMethod#format(String)} and the format

     * string {@code "%H.%n(%p)"}.

     */

    static String str(JavaMethod method) {

        return method.format("%H.%n(%p)");

    }

    /**

     * Wraps {@code obj} in a {@link Formatter} that standardizes formatting for certain objects.

     */

    static Formattable fmt(Object obj) {

        return new Formattable() {

            @Override

            public void formatTo(Formatter buf, int flags, int width, int precision) {

                if (obj instanceof Throwable) {

                    ByteArrayOutputStream baos = new ByteArrayOutputStream();

                    ((Throwable) obj).printStackTrace(new PrintStream(baos));

                    buf.format("%s", baos.toString());

                } else if (obj instanceof StackTraceElement[]) {

                    for (StackTraceElement e : (StackTraceElement[]) obj) {

                        buf.format("\t%s%n", e);

                    }

                } else if (obj instanceof JavaMethod) {

                    buf.format("%s", str((JavaMethod) obj));

                } else {

                    buf.format("%s", obj);

                }

            }

        };

    }

}