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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

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 *

 * 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.

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package org.graalvm.compiler.hotspot.amd64;

import static org.graalvm.compiler.hotspot.HotSpotBackend.Options.GraalArithmeticStubs;

import org.graalvm.compiler.api.replacements.Snippet;

import org.graalvm.compiler.core.amd64.AMD64LoweringProviderMixin;

import org.graalvm.compiler.core.common.spi.ForeignCallsProvider;

import org.graalvm.compiler.debug.DebugHandlersFactory;

import org.graalvm.compiler.graph.Node;

import org.graalvm.compiler.hotspot.GraalHotSpotVMConfig;

import org.graalvm.compiler.hotspot.HotSpotGraalRuntimeProvider;

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

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

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

import org.graalvm.compiler.hotspot.nodes.profiling.ProfileNode;

import org.graalvm.compiler.hotspot.replacements.profiling.ProbabilisticProfileSnippets;

import org.graalvm.compiler.nodes.StructuredGraph;

import org.graalvm.compiler.nodes.calc.FloatConvertNode;

import org.graalvm.compiler.nodes.extended.ForeignCallNode;

import org.graalvm.compiler.nodes.spi.LoweringTool;

import org.graalvm.compiler.options.OptionValues;

import org.graalvm.compiler.replacements.amd64.AMD64ArrayIndexOfDispatchNode;

import org.graalvm.compiler.replacements.amd64.AMD64ConvertSnippets;

import org.graalvm.compiler.replacements.nodes.UnaryMathIntrinsicNode;

import org.graalvm.compiler.replacements.nodes.UnaryMathIntrinsicNode.UnaryOperation;

import org.graalvm.compiler.serviceprovider.JavaVersionUtil;

import jdk.vm.ci.code.TargetDescription;

import jdk.vm.ci.hotspot.HotSpotConstantReflectionProvider;

import jdk.vm.ci.meta.MetaAccessProvider;

import jdk.vm.ci.meta.ResolvedJavaMethod;

public class AMD64HotSpotLoweringProvider extends DefaultHotSpotLoweringProvider implements AMD64LoweringProviderMixin {

    private AMD64ConvertSnippets.Templates convertSnippets;

    private ProbabilisticProfileSnippets.Templates profileSnippets;

    private AMD64X87MathSnippets.Templates mathSnippets;

    public AMD64HotSpotLoweringProvider(HotSpotGraalRuntimeProvider runtime, MetaAccessProvider metaAccess, ForeignCallsProvider foreignCalls, HotSpotRegistersProvider registers,

                    HotSpotConstantReflectionProvider constantReflection, TargetDescription target) {

        super(runtime, metaAccess, foreignCalls, registers, constantReflection, target);

    }

    @Override

    public void initialize(OptionValues options, Iterable<DebugHandlersFactory> factories, HotSpotProviders providers, GraalHotSpotVMConfig config) {

        convertSnippets = new AMD64ConvertSnippets.Templates(options, factories, providers, providers.getSnippetReflection(), providers.getCodeCache().getTarget());

        if (JavaVersionUtil.JAVA_SPEC <= 8) {

            // AOT only introduced in JDK 9

            profileSnippets = null;

        } else {

            profileSnippets = new ProbabilisticProfileSnippets.Templates(options, factories, providers, providers.getCodeCache().getTarget());

        }

        mathSnippets = new AMD64X87MathSnippets.Templates(options, factories, providers, providers.getSnippetReflection(), providers.getCodeCache().getTarget());

        super.initialize(options, factories, providers, config);

    }

    @Override

    public void lower(Node n, LoweringTool tool) {

        if (n instanceof FloatConvertNode) {

            convertSnippets.lower((FloatConvertNode) n, tool);

        } else if (profileSnippets != null && n instanceof ProfileNode) {

            profileSnippets.lower((ProfileNode) n, tool);

        } else if (n instanceof UnaryMathIntrinsicNode) {

            lowerUnaryMath((UnaryMathIntrinsicNode) n, tool);

        } else if (n instanceof AMD64ArrayIndexOfDispatchNode) {

            lowerArrayIndexOf((AMD64ArrayIndexOfDispatchNode) n);

        } else {

            super.lower(n, tool);

        }

    }

    private void lowerUnaryMath(UnaryMathIntrinsicNode math, LoweringTool tool) {

        if (tool.getLoweringStage() == LoweringTool.StandardLoweringStage.HIGH_TIER) {

            return;

        }

        StructuredGraph graph = math.graph();

        ResolvedJavaMethod method = graph.method();

        if (method != null) {

            if (method.getAnnotation(Snippet.class) != null) {

                // In the context of SnippetStub, i.e., Graal-generated stubs, use the LIR

                // lowering to emit the stub assembly code instead of the Node lowering.

                return;

            }

        }

        if (!GraalArithmeticStubs.getValue(graph.getOptions())) {

            switch (math.getOperation()) {

                case SIN:

                case COS:

                case TAN:

                    // Math.sin(), .cos() and .tan() guarantee a value within 1 ULP of the exact

                    // result, but x87 trigonometric FPU instructions are only that accurate within

                    // [-pi/4, pi/4]. The snippets fall back to a foreign call to HotSpot stubs

                    // should the inputs outside of that interval.

                    mathSnippets.lower(math, tool);

                    return;

                case LOG:

                    math.replaceAtUsages(graph.addOrUnique(new AMD64X87MathIntrinsicNode(math.getValue(), UnaryOperation.LOG)));

                    return;

                case LOG10:

                    math.replaceAtUsages(graph.addOrUnique(new AMD64X87MathIntrinsicNode(math.getValue(), UnaryOperation.LOG10)));

                    return;

            }

        }

        ForeignCallNode call = graph.add(new ForeignCallNode(foreignCalls, math.getOperation().foreignCallDescriptor, math.getValue()));

        graph.addAfterFixed(tool.lastFixedNode(), call);

        math.replaceAtUsages(call);

    }

    private void lowerArrayIndexOf(AMD64ArrayIndexOfDispatchNode dispatchNode) {

        StructuredGraph graph = dispatchNode.graph();

        ForeignCallNode call = graph.add(new ForeignCallNode(foreignCalls, dispatchNode.getStubCallDescriptor(), dispatchNode.getStubCallArgs()));

        graph.replaceFixed(dispatchNode, call);

    }

}