/*
 * Copyright (c) 2012, 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.phases.common;

import java.lang.reflect.*;
import java.util.*;
import java.util.concurrent.*;

import com.oracle.graal.api.code.*;
import com.oracle.graal.api.meta.*;
import com.oracle.graal.api.meta.ResolvedJavaType.Representation;
import com.oracle.graal.api.meta.JavaTypeProfile.ProfiledType;
import com.oracle.graal.debug.*;
import com.oracle.graal.graph.*;
import com.oracle.graal.nodes.*;
import com.oracle.graal.nodes.calc.*;
import com.oracle.graal.nodes.extended.*;
import com.oracle.graal.nodes.java.*;
import com.oracle.graal.nodes.java.MethodCallTargetNode.InvokeKind;
import com.oracle.graal.nodes.spi.*;
import com.oracle.graal.nodes.type.*;
import com.oracle.graal.nodes.util.*;
import com.oracle.graal.phases.*;

public class InliningUtil {

    private static final DebugMetric metricInliningTailDuplication = Debug.metric("InliningTailDuplication");

    public interface InliningCallback {
        StructuredGraph buildGraph(ResolvedJavaMethod method);
        double inliningWeight(ResolvedJavaMethod caller, ResolvedJavaMethod method, Invoke invoke);
        void recordMethodContentsAssumption(ResolvedJavaMethod method);
        void recordConcreteMethodAssumption(ResolvedJavaMethod method, ResolvedJavaType context, ResolvedJavaMethod impl);
    }

    public static String methodName(ResolvedJavaMethod method, Invoke invoke) {
        if (!Debug.isLogEnabled()) {
            return null;
        } else if (invoke != null && invoke.stateAfter() != null) {
            return methodName(invoke.stateAfter(), invoke.bci()) + ": " + MetaUtil.format("%H.%n(%p):%r", method) + " (" + method.getCodeSize() + " bytes)";
        } else {
            return MetaUtil.format("%H.%n(%p):%r", method) + " (" + method.getCodeSize() + " bytes)";
        }
    }

    public static String methodName(InlineInfo info) {
        if (!Debug.isLogEnabled()) {
            return null;
        } else if (info.invoke != null && info.invoke.stateAfter() != null) {
            return methodName(info.invoke.stateAfter(), info.invoke.bci()) + ": " + info.toString();
        } else {
            return info.toString();
        }
    }

    private static String methodName(FrameState frameState, int bci) {
        StringBuilder sb = new StringBuilder();
        if (frameState.outerFrameState() != null) {
            sb.append(methodName(frameState.outerFrameState(), frameState.outerFrameState().bci));
            sb.append("->");
        }
        sb.append(MetaUtil.format("%h.%n", frameState.method()));
        sb.append("@").append(bci);
        return sb.toString();
    }

    /**
     * Represents an opportunity for inlining at the given invoke, with the given weight and level.
     * The weight is the amortized weight of the additional code - so smaller is better.
     * The level is the number of nested inlinings that lead to this invoke.
     */
    public abstract static class InlineInfo implements Comparable<InlineInfo> {
        public final Invoke invoke;
        public final double weight;
        public final int level;

        public InlineInfo(Invoke invoke, double weight, int level) {
            this.invoke = invoke;
            this.weight = weight;
            this.level = level;
        }

        public abstract int compiledCodeSize();

        @Override
        public int compareTo(InlineInfo o) {
            return (weight < o.weight) ? -1 : (weight > o.weight) ? 1 : 0;
        }

        protected static StructuredGraph getGraph(final ResolvedJavaMethod concrete, final InliningCallback callback) {
            return Debug.scope("GetInliningGraph", concrete, new Callable<StructuredGraph>() {
                @Override
                public StructuredGraph call() throws Exception {
                    return callback.buildGraph(concrete);
                }
            });
        }

        public abstract boolean canDeopt();

        /**
         * Performs the inlining described by this object and returns the node that represents the return value of the
         * inlined method (or null for void methods and methods that have no non-exceptional exit).
         *
         * @param graph
         * @param runtime
         * @param callback
         */
        public abstract void inline(StructuredGraph graph, GraalCodeCacheProvider runtime, InliningCallback callback);
    }

    /**
     * Represents an inlining opportunity where the compiler can statically determine a monomorphic target method and
     * therefore is able to determine the called method exactly.
     */
    private static class ExactInlineInfo extends InlineInfo {
        public final ResolvedJavaMethod concrete;

        public ExactInlineInfo(Invoke invoke, double weight, int level, ResolvedJavaMethod concrete) {
            super(invoke, weight, level);
            this.concrete = concrete;
        }

        @Override
        public void inline(StructuredGraph compilerGraph, GraalCodeCacheProvider runtime, final InliningCallback callback) {
            StructuredGraph graph = getGraph(concrete, callback);
            assert !IntrinsificationPhase.canIntrinsify(invoke, concrete, runtime);
            callback.recordMethodContentsAssumption(concrete);
            InliningUtil.inline(invoke, graph, true);
        }

        @Override
        public int compiledCodeSize() {
            return concrete.getCompiledCodeSize();
        }

        @Override
        public String toString() {
            return "exact " + MetaUtil.format("%H.%n(%p):%r", concrete);
        }

        @Override
        public boolean canDeopt() {
            return false;
        }
    }

    /**
     * Represents an inlining opportunity for which profiling information suggests a monomorphic receiver, but for which
     * the receiver type cannot be proven. A type check guard will be generated if this inlining is performed.
     */
    private static class TypeGuardInlineInfo extends InlineInfo {
        public final ResolvedJavaMethod concrete;
        public final ResolvedJavaType type;

        public TypeGuardInlineInfo(Invoke invoke, double weight, int level, ResolvedJavaMethod concrete, ResolvedJavaType type) {
            super(invoke, weight, level);
            this.concrete = concrete;
            this.type = type;
        }

        @Override
        public int compiledCodeSize() {
            return concrete.getCompiledCodeSize();
        }

        @Override
        public void inline(StructuredGraph graph, GraalCodeCacheProvider runtime, InliningCallback callback) {
            // receiver null check must be before the type check
            InliningUtil.receiverNullCheck(invoke);
            ValueNode receiver = invoke.methodCallTarget().receiver();
            LoadHubNode receiverHub = graph.add(new LoadHubNode(receiver));
            ConstantNode typeHub = ConstantNode.forConstant(type.getEncoding(Representation.ObjectHub), runtime, graph);
            ObjectEqualsNode typeCheck = graph.unique(new ObjectEqualsNode(receiverHub, typeHub));
            FixedGuardNode guard = graph.add(new FixedGuardNode(typeCheck, DeoptimizationReason.TypeCheckedInliningViolated, DeoptimizationAction.InvalidateReprofile, invoke.leafGraphId()));
            ValueAnchorNode anchor = graph.add(new ValueAnchorNode());
            assert invoke.predecessor() != null;

            ValueNode anchoredReceiver = createAnchoredReceiver(graph, anchor, type, receiver, true);
            invoke.callTarget().replaceFirstInput(receiver, anchoredReceiver);

            graph.addBeforeFixed(invoke.node(), receiverHub);
            graph.addBeforeFixed(invoke.node(), guard);
            graph.addBeforeFixed(invoke.node(), anchor);

            StructuredGraph calleeGraph = getGraph(concrete, callback);
            assert !IntrinsificationPhase.canIntrinsify(invoke, concrete, runtime);
            callback.recordMethodContentsAssumption(concrete);
            InliningUtil.inline(invoke, calleeGraph, false);
        }

        @Override
        public String toString() {
            return "type-checked " + MetaUtil.format("%H.%n(%p):%r", concrete);
        }

        @Override
        public boolean canDeopt() {
            return true;
        }
    }

    /**
     * Polymorphic inlining of m methods with n type checks (n >= m) in case that the profiling information suggests a reasonable
     * amounts of different receiver types and different methods. If an unknown type is encountered a deoptimization is triggered.
     */
    private static class MultiTypeGuardInlineInfo extends InlineInfo {
        public final List<ResolvedJavaMethod> concretes;
        public final ProfiledType[] ptypes;
        public final int[] typesToConcretes;
        public final double notRecordedTypeProbability;

        public MultiTypeGuardInlineInfo(Invoke invoke, double weight, int level, List<ResolvedJavaMethod> concretes, ProfiledType[] ptypes,
                        int[] typesToConcretes, double notRecordedTypeProbability) {
            super(invoke, weight, level);
            assert concretes.size() > 0 && concretes.size() <= ptypes.length : "must have at least one method but no more than types methods";
            assert ptypes.length == typesToConcretes.length : "array lengths must match";

            this.concretes = concretes;
            this.ptypes = ptypes;
            this.typesToConcretes = typesToConcretes;
            this.notRecordedTypeProbability = notRecordedTypeProbability;
        }

        @Override
        public int compiledCodeSize() {
            int result = 0;
            for (ResolvedJavaMethod m: concretes) {
                result += m.getCompiledCodeSize();
            }
            return result;
        }

        @Override
        public void inline(StructuredGraph graph, GraalCodeCacheProvider runtime, InliningCallback callback) {
            int numberOfMethods = concretes.size();
            boolean hasReturnValue = invoke.node().kind() != Kind.Void;

            // receiver null check must be the first node
            InliningUtil.receiverNullCheck(invoke);
            if (numberOfMethods > 1 || shouldFallbackToInvoke()) {
                inlineMultipleMethods(graph, runtime, callback, numberOfMethods, hasReturnValue);
            } else {
                inlineSingleMethod(graph, runtime, callback);
            }
        }

        private boolean shouldFallbackToInvoke() {
            return notRecordedTypeProbability > 0;
        }

        private void inlineMultipleMethods(StructuredGraph graph, GraalCodeCacheProvider runtime, InliningCallback callback, int numberOfMethods, boolean hasReturnValue) {
            FixedNode continuation = invoke.next();

            ValueNode originalReceiver = invoke.methodCallTarget().receiver();
            // setup merge and phi nodes for results and exceptions
            MergeNode returnMerge = graph.add(new MergeNode());
            returnMerge.setProbability(invoke.probability());
            returnMerge.setStateAfter(invoke.stateAfter().duplicate(invoke.stateAfter().bci));

            PhiNode returnValuePhi = null;
            if (hasReturnValue) {
                returnValuePhi = graph.unique(new PhiNode(invoke.node().kind(), returnMerge));
            }

            MergeNode exceptionMerge = null;
            PhiNode exceptionObjectPhi = null;
            if (invoke instanceof InvokeWithExceptionNode) {
                InvokeWithExceptionNode invokeWithException = (InvokeWithExceptionNode) invoke;
                DispatchBeginNode exceptionEdge = invokeWithException.exceptionEdge();
                ExceptionObjectNode exceptionObject = (ExceptionObjectNode) exceptionEdge.next();

                exceptionMerge = graph.add(new MergeNode());
                exceptionMerge.setProbability(exceptionEdge.probability());

                FixedNode exceptionSux = exceptionObject.next();
                graph.addBeforeFixed(exceptionSux, exceptionMerge);
                exceptionObjectPhi = graph.unique(new PhiNode(Kind.Object, exceptionMerge));
                exceptionMerge.setStateAfter(exceptionEdge.stateAfter().duplicateModified(invoke.stateAfter().bci, true, Kind.Void, exceptionObjectPhi));
            }

            // create one separate block for each invoked method
            BeginNode[] calleeEntryNodes = new BeginNode[numberOfMethods];
            for (int i = 0; i < numberOfMethods; i++) {
                int predecessors = 0;
                double probability = 0;
                for (int j = 0; j < typesToConcretes.length; j++) {
                    if (typesToConcretes[j] == i) {
                        predecessors++;
                        probability += ptypes[j].getProbability();
                    }
                }

                calleeEntryNodes[i] = createInvocationBlock(graph, invoke, returnMerge, returnValuePhi, exceptionMerge, exceptionObjectPhi, predecessors, invoke.probability() * probability, true);
            }

            // create the successor for an unknown type
            FixedNode unknownTypeNode;
            if (shouldFallbackToInvoke()) {
                unknownTypeNode = createInvocationBlock(graph, invoke, returnMerge, returnValuePhi, exceptionMerge, exceptionObjectPhi, 1, notRecordedTypeProbability, false);
            } else {
                unknownTypeNode = graph.add(new DeoptimizeNode(DeoptimizationAction.InvalidateReprofile, DeoptimizationReason.TypeCheckedInliningViolated, invoke.leafGraphId()));
            }

            // replace the invoke exception edge
            if (invoke instanceof InvokeWithExceptionNode) {
                InvokeWithExceptionNode invokeWithExceptionNode = (InvokeWithExceptionNode) invoke;
                BeginNode exceptionEdge = invokeWithExceptionNode.exceptionEdge();
                ExceptionObjectNode exceptionObject = (ExceptionObjectNode) exceptionEdge.next();
                exceptionObject.replaceAtUsages(exceptionObjectPhi);
                exceptionObject.setNext(null);
                GraphUtil.killCFG(invokeWithExceptionNode.exceptionEdge());
            }

            // replace the invoke with a switch on the type of the actual receiver
            LoadHubNode receiverHub = graph.add(new LoadHubNode(invoke.methodCallTarget().receiver()));
            graph.addBeforeFixed(invoke.node(), receiverHub);
            FixedNode dispatchOnType = createDispatchOnType(graph, receiverHub, calleeEntryNodes, unknownTypeNode);

            assert invoke.next() == continuation;
            invoke.setNext(null);
            returnMerge.setNext(continuation);
            invoke.node().replaceAtUsages(returnValuePhi);
            invoke.node().replaceAndDelete(dispatchOnType);

            ArrayList<PiNode> replacements = new ArrayList<>();

            // do the actual inlining for every invoke
            for (int i = 0; i < calleeEntryNodes.length; i++) {
                BeginNode node = calleeEntryNodes[i];
                Invoke invokeForInlining = (Invoke) node.next();

                ResolvedJavaType commonType = getLeastCommonType(i);
                ValueNode receiver = invokeForInlining.methodCallTarget().receiver();
                boolean exact = getTypeCount(i) == 1;
                PiNode anchoredReceiver = createAnchoredReceiver(graph, node, commonType, receiver, exact);
                invokeForInlining.callTarget().replaceFirstInput(receiver, anchoredReceiver);

                ResolvedJavaMethod concrete = concretes.get(i);
                StructuredGraph calleeGraph = getGraph(concrete, callback);
                callback.recordMethodContentsAssumption(concrete);
                assert !IntrinsificationPhase.canIntrinsify(invokeForInlining, concrete, runtime);
                InliningUtil.inline(invokeForInlining, calleeGraph, false);
                replacements.add(anchoredReceiver);
            }
            if (shouldFallbackToInvoke()) {
                replacements.add(null);
            }
            if (GraalOptions.OptTailDuplication) {
                /*
                 * We might want to perform tail duplication at the merge after a type switch, if there are invokes that would
                 * benefit from the improvement in type information.
                 */
                FixedNode current = returnMerge;
                int opportunities = 0;
                do {
                    if (current instanceof InvokeNode && ((InvokeNode) current).methodCallTarget().receiver() == originalReceiver) {
                        opportunities++;
                    } else if (current.inputs().contains(originalReceiver)) {
                        opportunities++;
                    }
                    current = ((FixedWithNextNode) current).next();
                } while (current instanceof FixedWithNextNode);
                if (opportunities > 0) {
                    metricInliningTailDuplication.increment();
                    Debug.log("MultiTypeGuardInlineInfo starting tail duplication (%d opportunities)", opportunities);
                    TailDuplicationPhase.tailDuplicate(returnMerge, TailDuplicationPhase.TRUE_DECISION, replacements);
                }
            }
        }

        private int getTypeCount(int concreteMethodIndex) {
            int count = 0;
            for (int i = 0; i < typesToConcretes.length; i++) {
                if (typesToConcretes[i] == concreteMethodIndex) {
                    count++;
                }
            }
            return count;
        }

        private ResolvedJavaType getLeastCommonType(int concreteMethodIndex) {
            ResolvedJavaType commonType = null;
            for (int i = 0; i < typesToConcretes.length; i++) {
                if (typesToConcretes[i] == concreteMethodIndex) {
                    if (commonType == null) {
                        commonType = ptypes[i].getType();
                    } else {
                        commonType = commonType.findLeastCommonAncestor(ptypes[i].getType());
                    }
                }
            }
            assert commonType != null;
            return commonType;
        }

        private void inlineSingleMethod(StructuredGraph graph, GraalCodeCacheProvider runtime, InliningCallback callback) {
            assert concretes.size() == 1 && ptypes.length > 1 && !shouldFallbackToInvoke() && notRecordedTypeProbability == 0;

            MergeNode calleeEntryNode = graph.add(new MergeNode());
            calleeEntryNode.setProbability(invoke.probability());
            LoadHubNode receiverHub = graph.add(new LoadHubNode(invoke.methodCallTarget().receiver()));
            graph.addBeforeFixed(invoke.node(), receiverHub);

            FixedNode unknownTypeNode = graph.add(new DeoptimizeNode(DeoptimizationAction.InvalidateReprofile, DeoptimizationReason.TypeCheckedInliningViolated, invoke.leafGraphId()));
            FixedNode dispatchOnType = createDispatchOnType(graph, receiverHub, new BeginNode[] {calleeEntryNode}, unknownTypeNode);

            FixedWithNextNode pred = (FixedWithNextNode) invoke.node().predecessor();
            pred.setNext(dispatchOnType);
            calleeEntryNode.setNext(invoke.node());

            ResolvedJavaMethod concrete = concretes.get(0);
            StructuredGraph calleeGraph = getGraph(concrete, callback);
            assert !IntrinsificationPhase.canIntrinsify(invoke, concrete, runtime);
            callback.recordMethodContentsAssumption(concrete);
            InliningUtil.inline(invoke, calleeGraph, false);
        }

        private FixedNode createDispatchOnType(StructuredGraph graph, LoadHubNode objectClassNode, BeginNode[] calleeEntryNodes, FixedNode unknownTypeSux) {
            assert ptypes.length > 1;

            ResolvedJavaType[] types = new ResolvedJavaType[ptypes.length];
            double[] probabilities = new double[ptypes.length + 1];
            BeginNode[] successors = new BeginNode[ptypes.length + 1];
            int[] keySuccessors = new int[ptypes.length + 1];
            for (int i = 0; i < ptypes.length; i++) {
                types[i] = ptypes[i].getType();
                probabilities[i] = ptypes[i].getProbability();
                FixedNode entry = calleeEntryNodes[typesToConcretes[i]];
                if (entry instanceof MergeNode) {
                    EndNode endNode = graph.add(new EndNode());
                    ((MergeNode) entry).addForwardEnd(endNode);
                    entry = endNode;
                }
                successors[i] = BeginNode.begin(entry);
                keySuccessors[i] = i;
            }
            assert !(unknownTypeSux instanceof MergeNode);
            successors[successors.length - 1] = BeginNode.begin(unknownTypeSux);
            probabilities[successors.length - 1] = notRecordedTypeProbability;
            keySuccessors[successors.length - 1] = successors.length - 1;

            TypeSwitchNode typeSwitch = graph.add(new TypeSwitchNode(objectClassNode, successors, probabilities, types, probabilities, keySuccessors));

            return typeSwitch;
        }

        private static BeginNode createInvocationBlock(StructuredGraph graph, Invoke invoke, MergeNode returnMerge, PhiNode returnValuePhi,
                        MergeNode exceptionMerge, PhiNode exceptionObjectPhi, int predecessors, double probability, boolean useForInlining) {
            Invoke duplicatedInvoke = duplicateInvokeForInlining(graph, invoke, exceptionMerge, exceptionObjectPhi, useForInlining, probability);
            BeginNode calleeEntryNode = graph.add(predecessors > 1 ? new MergeNode() : new BeginNode());
            calleeEntryNode.setNext(duplicatedInvoke.node());
            calleeEntryNode.setProbability(probability);

            EndNode endNode = graph.add(new EndNode());
            endNode.setProbability(probability);

            duplicatedInvoke.setNext(endNode);
            returnMerge.addForwardEnd(endNode);

            if (returnValuePhi != null) {
                returnValuePhi.addInput(duplicatedInvoke.node());
            }
            return calleeEntryNode;
        }

        private static Invoke duplicateInvokeForInlining(StructuredGraph graph, Invoke invoke, MergeNode exceptionMerge, PhiNode exceptionObjectPhi, boolean useForInlining, double probability) {
            Invoke result = (Invoke) invoke.node().copyWithInputs();
            Node callTarget = result.callTarget().copyWithInputs();
            result.node().replaceFirstInput(result.callTarget(), callTarget);
            result.setUseForInlining(useForInlining);
            result.setProbability(probability);

            Kind kind = invoke.node().kind();
            if (!kind.isVoid()) {
                FrameState stateAfter = invoke.stateAfter();
                stateAfter = stateAfter.duplicate(stateAfter.bci);
                stateAfter.replaceFirstInput(invoke.node(), result.node());
                result.setStateAfter(stateAfter);
            }

            if (invoke instanceof InvokeWithExceptionNode) {
                assert exceptionMerge != null && exceptionObjectPhi != null;

                InvokeWithExceptionNode invokeWithException = (InvokeWithExceptionNode) invoke;
                BeginNode exceptionEdge = invokeWithException.exceptionEdge();
                ExceptionObjectNode exceptionObject = (ExceptionObjectNode) exceptionEdge.next();
                FrameState stateAfterException = exceptionObject.stateAfter();

                BeginNode newExceptionEdge = (BeginNode) exceptionEdge.copyWithInputs();
                ExceptionObjectNode newExceptionObject = (ExceptionObjectNode) exceptionObject.copyWithInputs();
                // set new state (pop old exception object, push new one)
                newExceptionObject.setStateAfter(stateAfterException.duplicateModified(stateAfterException.bci, stateAfterException.rethrowException(), Kind.Object, newExceptionObject));
                newExceptionEdge.setNext(newExceptionObject);

                EndNode endNode = graph.add(new EndNode());
                newExceptionObject.setNext(endNode);
                exceptionMerge.addForwardEnd(endNode);
                exceptionObjectPhi.addInput(newExceptionObject);

                ((InvokeWithExceptionNode) result).setExceptionEdge(newExceptionEdge);
            }
            return result;
        }

        @Override
        public String toString() {
            StringBuilder builder = new StringBuilder(shouldFallbackToInvoke() ? "megamorphic" : "polymorphic");
            builder.append(String.format(", %d methods with %d type checks:", concretes.size(), ptypes.length));
            for (int i = 0; i < concretes.size(); i++) {
                builder.append(MetaUtil.format("  %H.%n(%p):%r", concretes.get(i)));
            }
            return builder.toString();
        }

        @Override
        public boolean canDeopt() {
            return true;
        }
    }


    /**
     * Represents an inlining opportunity where the current class hierarchy leads to a monomorphic target method,
     * but for which an assumption has to be registered because of non-final classes.
     */
    private static class AssumptionInlineInfo extends ExactInlineInfo {
        public final ResolvedJavaType context;

        public AssumptionInlineInfo(Invoke invoke, double weight, int level, ResolvedJavaType context, ResolvedJavaMethod concrete) {
            super(invoke, weight, level, concrete);
            this.context = context;
        }

        @Override
        public void inline(StructuredGraph graph, GraalCodeCacheProvider runtime, InliningCallback callback) {
            if (Debug.isLogEnabled()) {
                String targetName = MetaUtil.format("%H.%n(%p):%r", invoke.methodCallTarget().targetMethod());
                String concreteName = MetaUtil.format("%H.%n(%p):%r", concrete);
                Debug.log("recording concrete method assumption: %s on receiver type %s -> %s", targetName, context, concreteName);
            }
            callback.recordConcreteMethodAssumption(invoke.methodCallTarget().targetMethod(), context, concrete);

            super.inline(graph, runtime, callback);
        }

        @Override
        public String toString() {
            return "assumption " + MetaUtil.format("%H.%n(%p):%r", concrete);
        }

        @Override
        public boolean canDeopt() {
            return true;
        }
    }

    /**
     * Determines if inlining is possible at the given invoke node.
     * @param invoke the invoke that should be inlined
     * @param level the number of nested inlinings that lead to this invoke, or 0 if the invoke was part of the initial graph
     * @param runtime a GraalRuntime instance used to determine of the invoke can be inlined and/or should be intrinsified
     * @param callback a callback that is used to determine the weight of a specific inlining
     * @return an instance of InlineInfo, or null if no inlining is possible at the given invoke
     */
    public static InlineInfo getInlineInfo(Invoke invoke, int level, GraalCodeCacheProvider runtime, Assumptions assumptions, InliningCallback callback, OptimisticOptimizations optimisticOpts) {
        if (!(invoke.callTarget() instanceof MethodCallTargetNode)) {
            // The invoke has already been lowered , or has been created as a low-level node. We have no method information.
            return null;
        }
        ResolvedJavaMethod parent = invoke.stateAfter().method();
        MethodCallTargetNode callTarget = invoke.methodCallTarget();
        ResolvedJavaMethod targetMethod = callTarget.targetMethod();
        if (targetMethod == null) {
            return null;
        }
        if (!checkInvokeConditions(invoke)) {
            return null;
        }

        if (callTarget.invokeKind() == InvokeKind.Special || targetMethod.canBeStaticallyBound()) {
            if (checkTargetConditions(invoke, targetMethod, optimisticOpts)) {
                double weight = callback == null ? 0 : callback.inliningWeight(parent, targetMethod, invoke);
                return new ExactInlineInfo(invoke, weight, level, targetMethod);
            }
            return null;
        }
        ObjectStamp receiverStamp = callTarget.receiver().objectStamp();
        ResolvedJavaType receiverType = receiverStamp.type();
        if (receiverStamp.isExactType()) {
            assert receiverType.isSubtypeOf(targetMethod.getDeclaringClass()) : receiverType + " subtype of " + targetMethod.getDeclaringClass() + " for " + targetMethod;
            ResolvedJavaMethod resolved = receiverType.resolveMethod(targetMethod);
            if (checkTargetConditions(invoke, resolved, optimisticOpts)) {
                double weight = callback == null ? 0 : callback.inliningWeight(parent, resolved, invoke);
                return new ExactInlineInfo(invoke, weight, level, resolved);
            }
            return null;
        }
        ResolvedJavaType holder = targetMethod.getDeclaringClass();

        if (receiverStamp.type() != null) {
            // the invoke target might be more specific than the holder (happens after inlining: locals lose their declared type...)
            // TODO (lstadler) fix this
            if (receiverType != null && receiverType.isSubtypeOf(holder)) {
                holder = receiverType;
            }
        }
        // TODO (thomaswue) fix this
        if (assumptions != null) {
            ResolvedJavaMethod concrete = holder.findUniqueConcreteMethod(targetMethod);
            if (concrete != null) {
                if (checkTargetConditions(invoke, concrete, optimisticOpts)) {
                    double weight = callback == null ? 0 : callback.inliningWeight(parent, concrete, invoke);
                    return new AssumptionInlineInfo(invoke, weight, level, holder, concrete);
                }
                return null;
            }
        }

        // type check based inlining
        return getTypeCheckedInlineInfo(invoke, level, callback, parent, targetMethod, optimisticOpts);
    }

    private static InlineInfo getTypeCheckedInlineInfo(Invoke invoke, int level, InliningCallback callback, ResolvedJavaMethod parent, ResolvedJavaMethod targetMethod, OptimisticOptimizations optimisticOpts) {
        ProfilingInfo profilingInfo = parent.getProfilingInfo();
        JavaTypeProfile typeProfile = profilingInfo.getTypeProfile(invoke.bci());
        if (typeProfile != null) {
            ProfiledType[] ptypes = typeProfile.getTypes();

            if (ptypes != null && ptypes.length > 0) {
                double notRecordedTypeProbability = typeProfile.getNotRecordedProbability();
                if (ptypes.length == 1 && notRecordedTypeProbability == 0) {
                    if (optimisticOpts.inlineMonomorphicCalls()) {
                        ResolvedJavaType type = ptypes[0].getType();
                        ResolvedJavaMethod concrete = type.resolveMethod(targetMethod);
                        if (checkTargetConditions(invoke, concrete, optimisticOpts)) {
                            double weight = callback == null ? 0 : callback.inliningWeight(parent, concrete, invoke);
                            return new TypeGuardInlineInfo(invoke, weight, level, concrete, type);
                        }

                        Debug.log("not inlining %s because method can't be inlined", methodName(targetMethod, invoke));
                        return null;
                    } else {
                        Debug.log("not inlining %s because GraalOptions.InlineMonomorphicCalls == false", methodName(targetMethod, invoke));
                        return null;
                    }
                } else {
                    invoke.setMegamorphic(true);
                    if (optimisticOpts.inlinePolymorphicCalls() && notRecordedTypeProbability == 0 || optimisticOpts.inlineMegamorphicCalls() && notRecordedTypeProbability > 0) {
                        // TODO (chaeubl) inlining of multiple methods should work differently
                        // 1. check which methods can be inlined
                        // 2. for those methods, use weight and probability to compute which of them should be inlined
                        // 3. do the inlining
                        //    a) all seen methods can be inlined -> do so and guard with deopt
                        //    b) some methods can be inlined -> inline them and fall back to invocation if violated
                        // TODO (chaeubl) sort types by probability

                        // determine concrete methods and map type to specific method
                        ArrayList<ResolvedJavaMethod> concreteMethods = new ArrayList<>();
                        int[] typesToConcretes = new int[ptypes.length];
                        for (int i = 0; i < ptypes.length; i++) {
                            ResolvedJavaMethod concrete = ptypes[i].getType().resolveMethod(targetMethod);

                            int index = concreteMethods.indexOf(concrete);
                            if (index < 0) {
                                index = concreteMethods.size();
                                concreteMethods.add(concrete);
                            }
                            typesToConcretes[i] = index;
                        }

                        double totalWeight = 0;
                        boolean canInline = true;
                        for (ResolvedJavaMethod concrete: concreteMethods) {
                            if (!checkTargetConditions(invoke, concrete, optimisticOpts)) {
                                canInline = false;
                                break;
                            }
                            totalWeight += callback == null ? 0 : callback.inliningWeight(parent, concrete, invoke);
                        }

                        if (canInline) {
                            return new MultiTypeGuardInlineInfo(invoke, totalWeight, level, concreteMethods, ptypes, typesToConcretes, notRecordedTypeProbability);
                        } else {
                            Debug.log("not inlining %s because it is a polymorphic method call and at least one invoked method cannot be inlined", methodName(targetMethod, invoke));
                            return null;
                        }
                    } else {
                        if (!optimisticOpts.inlinePolymorphicCalls() && notRecordedTypeProbability == 0) {
                            Debug.log("not inlining %s because GraalOptions.InlinePolymorphicCalls == false", methodName(targetMethod, invoke));
                        } else {
                            Debug.log("not inlining %s because GraalOptions.InlineMegamorphicCalls == false", methodName(targetMethod, invoke));
                        }
                        return null;
                    }
                }
            }

            Debug.log("not inlining %s because no types/probabilities were recorded", methodName(targetMethod, invoke));
            return null;
        } else {
            Debug.log("not inlining %s because no type profile exists", methodName(targetMethod, invoke));
            return null;
        }
    }

    private static PiNode createAnchoredReceiver(StructuredGraph graph, FixedNode anchor, ResolvedJavaType commonType, ValueNode receiver, boolean exact) {
        // to avoid that floating reads on receiver fields float above the type check
        return graph.unique(new PiNode(receiver, anchor, exact ? StampFactory.exactNonNull(commonType) : StampFactory.declaredNonNull(commonType)));
    }

    private static boolean checkInvokeConditions(Invoke invoke) {
        if (invoke.stateAfter() == null) {
            Debug.log("not inlining %s because the invoke has no after state", methodName(invoke.methodCallTarget().targetMethod(), invoke));
            return false;
        }
        if (invoke.predecessor() == null) {
            Debug.log("not inlining %s because the invoke is dead code", methodName(invoke.methodCallTarget().targetMethod(), invoke));
            return false;
        }
        if (!invoke.useForInlining()) {
            Debug.log("not inlining %s because invoke is marked to be not used for inlining", methodName(invoke.methodCallTarget().targetMethod(), invoke));
            return false;
        }
        return true;
    }

    private static boolean checkTargetConditions(Invoke invoke, JavaMethod method, OptimisticOptimizations optimisticOpts) {
        if (method == null) {
            Debug.log("not inlining because method is not resolved");
            return false;
        }
        if (!(method instanceof ResolvedJavaMethod)) {
            Debug.log("not inlining %s because it is unresolved", method.toString());
            return false;
        }
        ResolvedJavaMethod resolvedMethod = (ResolvedJavaMethod) method;
        if (Modifier.isNative(resolvedMethod.getModifiers())) {
            Debug.log("not inlining %s because it is a native method", methodName(resolvedMethod, invoke));
            return false;
        }
        if (Modifier.isAbstract(resolvedMethod.getModifiers())) {
            Debug.log("not inlining %s because it is an abstract method", methodName(resolvedMethod, invoke));
            return false;
        }
        if (!resolvedMethod.getDeclaringClass().isInitialized()) {
            Debug.log("not inlining %s because of non-initialized class", methodName(resolvedMethod, invoke));
            return false;
        }
        if (!resolvedMethod.canBeInlined()) {
            Debug.log("not inlining %s because it is marked non-inlinable", methodName(resolvedMethod, invoke));
            return false;
        }
        if (computeRecursiveInliningLevel(invoke.stateAfter(), (ResolvedJavaMethod) method) > GraalOptions.MaximumRecursiveInlining) {
            Debug.log("not inlining %s because it exceeds the maximum recursive inlining depth", methodName(resolvedMethod, invoke));
            return false;
        }
        OptimisticOptimizations calleeOpts = new OptimisticOptimizations(resolvedMethod);
        if (calleeOpts.lessOptimisticThan(optimisticOpts)) {
            Debug.log("not inlining %s because callee uses less optimistic optimizations than caller", methodName(resolvedMethod, invoke));
            return false;
        }

        return true;
    }

    private static int computeRecursiveInliningLevel(FrameState state, ResolvedJavaMethod method) {
        assert state != null;

        int count = 0;
        FrameState curState = state;
        while (curState != null) {
            if (curState.method() == method) {
                count++;
            }
            curState = curState.outerFrameState();
        }
        return count;
    }

    /**
     * Performs an actual inlining, thereby replacing the given invoke with the given inlineGraph.
     *
     * @param invoke the invoke that will be replaced
     * @param inlineGraph the graph that the invoke will be replaced with
     * @param receiverNullCheck true if a null check needs to be generated for non-static inlinings, false if no such check is required
     */
    public static void inline(Invoke invoke, StructuredGraph inlineGraph, boolean receiverNullCheck) {
        NodeInputList<ValueNode> parameters = invoke.callTarget().arguments();
        StructuredGraph graph = (StructuredGraph) invoke.node().graph();

        FrameState stateAfter = invoke.stateAfter();
        assert stateAfter.isAlive();

        IdentityHashMap<Node, Node> replacements = new IdentityHashMap<>();
        ArrayList<Node> nodes = new ArrayList<>();
        ReturnNode returnNode = null;
        UnwindNode unwindNode = null;
        StartNode entryPointNode = inlineGraph.start();
        FixedNode firstCFGNode = entryPointNode.next();
        for (Node node : inlineGraph.getNodes()) {
            if (node == entryPointNode || node == entryPointNode.stateAfter()) {
                // Do nothing.
            } else if (node instanceof LocalNode) {
                replacements.put(node, parameters.get(((LocalNode) node).index()));
            } else {
                nodes.add(node);
                if (node instanceof ReturnNode) {
                    assert returnNode == null;
                    returnNode = (ReturnNode) node;
                } else if (node instanceof UnwindNode) {
                    assert unwindNode == null;
                    unwindNode = (UnwindNode) node;
                }
            }
        }
        replacements.put(entryPointNode, BeginNode.prevBegin(invoke.node())); // ensure proper anchoring of things that where anchored to the StartNode

        assert invoke.node().successors().first() != null : invoke;
        assert invoke.node().predecessor() != null;

        Map<Node, Node> duplicates = graph.addDuplicates(nodes, replacements);
        FixedNode firstCFGNodeDuplicate = (FixedNode) duplicates.get(firstCFGNode);
        if (receiverNullCheck) {
            receiverNullCheck(invoke);
        }
        invoke.node().replaceAtPredecessor(firstCFGNodeDuplicate);

        FrameState stateAtExceptionEdge = null;
        if (invoke instanceof InvokeWithExceptionNode) {
            InvokeWithExceptionNode invokeWithException = ((InvokeWithExceptionNode) invoke);
            if (unwindNode != null) {
                assert unwindNode.predecessor() != null;
                assert invokeWithException.exceptionEdge().successors().count() == 1;
                ExceptionObjectNode obj = (ExceptionObjectNode) invokeWithException.exceptionEdge().next();
                stateAtExceptionEdge = obj.stateAfter();
                UnwindNode unwindDuplicate = (UnwindNode) duplicates.get(unwindNode);
                obj.replaceAtUsages(unwindDuplicate.exception());
                unwindDuplicate.clearInputs();
                Node n = obj.next();
                obj.setNext(null);
                unwindDuplicate.replaceAndDelete(n);
            } else {
                invokeWithException.killExceptionEdge();
            }
        } else {
            if (unwindNode != null) {
                UnwindNode unwindDuplicate = (UnwindNode) duplicates.get(unwindNode);
                DeoptimizeNode deoptimizeNode = new DeoptimizeNode(DeoptimizationAction.InvalidateRecompile, DeoptimizationReason.NotCompiledExceptionHandler, invoke.leafGraphId());
                unwindDuplicate.replaceAndDelete(graph.add(deoptimizeNode));
                // move the deopt upwards if there is a monitor exit that tries to use the "after exception" frame state
                // (because there is no "after exception" frame state!)
                if (deoptimizeNode.predecessor() instanceof MonitorExitNode) {
                    MonitorExitNode monitorExit = (MonitorExitNode) deoptimizeNode.predecessor();
                    if (monitorExit.stateAfter() != null && monitorExit.stateAfter().bci == FrameState.AFTER_EXCEPTION_BCI) {
                        FrameState monitorFrameState = monitorExit.stateAfter();
                        graph.removeFixed(monitorExit);
                        monitorFrameState.safeDelete();
                    }
                }
            }
        }

        FrameState outerFrameState = null;
        double invokeProbability = invoke.node().probability();
        for (Node node : duplicates.values()) {
            if (GraalOptions.ProbabilityAnalysis) {
                if (node instanceof FixedNode) {
                    FixedNode fixed = (FixedNode) node;
                    double newProbability = fixed.probability() * invokeProbability;
                    if (GraalOptions.LimitInlinedProbability) {
                        newProbability = Math.min(newProbability, invokeProbability);
                    }
                    fixed.setProbability(newProbability);
                }
            }
            if (node instanceof FrameState) {
                FrameState frameState = (FrameState) node;
                assert frameState.bci != FrameState.BEFORE_BCI;
                if (frameState.bci == FrameState.AFTER_BCI) {
                    frameState.replaceAndDelete(stateAfter);
                } else if (frameState.bci == FrameState.AFTER_EXCEPTION_BCI) {
                    if (frameState.isAlive()) {
                        assert stateAtExceptionEdge != null;
                        frameState.replaceAndDelete(stateAtExceptionEdge);
                    } else {
                        assert stateAtExceptionEdge == null;
                    }
                } else {
                    // only handle the outermost frame states
                    if (frameState.outerFrameState() == null) {
                        assert frameState.method() == inlineGraph.method();
                        if (outerFrameState == null) {
                            outerFrameState = stateAfter.duplicateModified(invoke.bci(), stateAfter.rethrowException(), invoke.node().kind());
                            outerFrameState.setDuringCall(true);
                        }
                        frameState.setOuterFrameState(outerFrameState);
                    }
                }
            }
        }

        Node returnValue = null;
        if (returnNode != null) {
            if (returnNode.result() instanceof LocalNode) {
                returnValue = replacements.get(returnNode.result());
            } else {
                returnValue = duplicates.get(returnNode.result());
            }
            invoke.node().replaceAtUsages(returnValue);
            Node returnDuplicate = duplicates.get(returnNode);
            returnDuplicate.clearInputs();
            Node n = invoke.next();
            invoke.setNext(null);
            returnDuplicate.replaceAndDelete(n);
        }

        invoke.node().replaceAtUsages(null);
        GraphUtil.killCFG(invoke.node());
    }

    public static void receiverNullCheck(Invoke invoke) {
        MethodCallTargetNode callTarget = invoke.methodCallTarget();
        StructuredGraph graph = (StructuredGraph) invoke.graph();
        NodeInputList<ValueNode> parameters = callTarget.arguments();
        ValueNode firstParam = parameters.size() <= 0 ? null : parameters.get(0);
        if (!callTarget.isStatic() && firstParam.kind() == Kind.Object && !firstParam.objectStamp().nonNull()) {
            graph.addBeforeFixed(invoke.node(), graph.add(new FixedGuardNode(graph.unique(new IsNullNode(firstParam)), DeoptimizationReason.NullCheckException, DeoptimizationAction.InvalidateReprofile, true, invoke.leafGraphId())));
        }
    }
}