Mercurial > hg > graal-compiler
view graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/inlining/walker/InliningData.java @ 18191:839f97696479
Rename ResolvedJavaMethod.resolvedMethod() to resolveConcreteMethod() the reflect its actual behavior.
author | Josef Eisl <josef.eisl@jku.at> |
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date | Wed, 29 Oct 2014 18:54:32 +0100 |
parents | c88ab4f1f04a |
children | 3aaf2747961c |
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/* * Copyright (c) 2011, 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.inlining.walker; import com.oracle.graal.api.code.Assumptions; import com.oracle.graal.api.code.BailoutException; import com.oracle.graal.api.meta.JavaTypeProfile; import com.oracle.graal.api.meta.ResolvedJavaMethod; import com.oracle.graal.api.meta.ResolvedJavaType; import com.oracle.graal.compiler.common.GraalInternalError; import com.oracle.graal.compiler.common.type.ObjectStamp; import com.oracle.graal.debug.Debug; import com.oracle.graal.debug.DebugMetric; import com.oracle.graal.graph.Graph; import com.oracle.graal.graph.Node; import com.oracle.graal.nodes.*; import com.oracle.graal.nodes.java.AbstractNewObjectNode; import com.oracle.graal.nodes.java.MethodCallTargetNode; import com.oracle.graal.nodes.virtual.AllocatedObjectNode; import com.oracle.graal.nodes.virtual.VirtualObjectNode; import com.oracle.graal.phases.OptimisticOptimizations; import com.oracle.graal.phases.common.CanonicalizerPhase; import com.oracle.graal.phases.common.inlining.InliningUtil; import com.oracle.graal.phases.common.inlining.info.*; import com.oracle.graal.phases.common.inlining.info.elem.Inlineable; import com.oracle.graal.phases.common.inlining.info.elem.InlineableGraph; import com.oracle.graal.phases.common.inlining.info.elem.InlineableMacroNode; import com.oracle.graal.phases.common.inlining.policy.InliningPolicy; import com.oracle.graal.phases.tiers.HighTierContext; import com.oracle.graal.phases.util.Providers; import java.util.*; import static com.oracle.graal.compiler.common.GraalOptions.*; import static com.oracle.graal.phases.common.inlining.walker.CallsiteHolderDummy.DUMMY_CALLSITE_HOLDER; /** * <p> * The space of inlining decisions is explored depth-first with the help of a stack realized by * {@link InliningData}. At any point in time, the topmost element of that stack consists of: * <ul> * <li>the callsite under consideration is tracked as a {@link MethodInvocation}.</li> * <li> * one or more {@link CallsiteHolder}s, all of them associated to the callsite above. Why more than * one? Depending on the type-profile for the receiver more than one concrete method may be feasible * target.</li> * </ul> * </p> * * <p> * The bottom element in the stack consists of: * <ul> * <li> * a single {@link MethodInvocation} (the * {@link com.oracle.graal.phases.common.inlining.walker.MethodInvocation#isRoot root} one, ie the * unknown caller of the root graph)</li> * <li> * a single {@link CallsiteHolder} (the root one, for the method on which inlining was called)</li> * </ul> * </p> * * @see #moveForward() */ public class InliningData { // Metrics private static final DebugMetric metricInliningPerformed = Debug.metric("InliningPerformed"); private static final DebugMetric metricInliningRuns = Debug.metric("InliningRuns"); private static final DebugMetric metricInliningConsidered = Debug.metric("InliningConsidered"); /** * Call hierarchy from outer most call (i.e., compilation unit) to inner most callee. */ private final ArrayDeque<CallsiteHolder> graphQueue = new ArrayDeque<>(); private final ArrayDeque<MethodInvocation> invocationQueue = new ArrayDeque<>(); private final HighTierContext context; private final int maxMethodPerInlining; private final CanonicalizerPhase canonicalizer; private final InliningPolicy inliningPolicy; private int maxGraphs; public InliningData(StructuredGraph rootGraph, HighTierContext context, int maxMethodPerInlining, CanonicalizerPhase canonicalizer, InliningPolicy inliningPolicy) { assert rootGraph != null; this.context = context; this.maxMethodPerInlining = maxMethodPerInlining; this.canonicalizer = canonicalizer; this.inliningPolicy = inliningPolicy; this.maxGraphs = 1; Assumptions rootAssumptions = context.getAssumptions(); invocationQueue.push(new MethodInvocation(null, rootAssumptions, 1.0, 1.0, null)); graphQueue.push(new CallsiteHolderExplorable(rootGraph, 1.0, 1.0, null)); } public static boolean isFreshInstantiation(ValueNode arg) { return (arg instanceof AbstractNewObjectNode) || (arg instanceof AllocatedObjectNode) || (arg instanceof VirtualObjectNode); } private String checkTargetConditionsHelper(ResolvedJavaMethod method) { if (method == null) { return "the method is not resolved"; } else if (method.isNative() && (!Intrinsify.getValue() || !InliningUtil.canIntrinsify(context.getReplacements(), method))) { return "it is a non-intrinsic native method"; } else if (method.isAbstract()) { return "it is an abstract method"; } else if (!method.getDeclaringClass().isInitialized()) { return "the method's class is not initialized"; } else if (!method.canBeInlined()) { return "it is marked non-inlinable"; } else if (countRecursiveInlining(method) > MaximumRecursiveInlining.getValue()) { return "it exceeds the maximum recursive inlining depth"; } else if (new OptimisticOptimizations(method.getProfilingInfo()).lessOptimisticThan(context.getOptimisticOptimizations())) { return "the callee uses less optimistic optimizations than caller"; } else { return null; } } private boolean checkTargetConditions(Invoke invoke, ResolvedJavaMethod method) { final String failureMessage = checkTargetConditionsHelper(method); if (failureMessage == null) { return true; } else { InliningUtil.logNotInlined(invoke, inliningDepth(), method, failureMessage); return false; } } /** * Determines if inlining is possible at the given invoke node. * * @param invoke the invoke that should be inlined * @return an instance of InlineInfo, or null if no inlining is possible at the given invoke */ private InlineInfo getInlineInfo(Invoke invoke, Assumptions assumptions) { final String failureMessage = InliningUtil.checkInvokeConditions(invoke); if (failureMessage != null) { InliningUtil.logNotInlinedMethod(invoke, failureMessage); return null; } MethodCallTargetNode callTarget = (MethodCallTargetNode) invoke.callTarget(); ResolvedJavaMethod targetMethod = callTarget.targetMethod(); if (callTarget.invokeKind() == CallTargetNode.InvokeKind.Special || targetMethod.canBeStaticallyBound()) { return getExactInlineInfo(invoke, targetMethod); } assert callTarget.invokeKind() == CallTargetNode.InvokeKind.Virtual || callTarget.invokeKind() == CallTargetNode.InvokeKind.Interface; ResolvedJavaType holder = targetMethod.getDeclaringClass(); if (!(callTarget.receiver().stamp() instanceof ObjectStamp)) { return null; } ObjectStamp receiverStamp = (ObjectStamp) callTarget.receiver().stamp(); if (receiverStamp.alwaysNull()) { // Don't inline if receiver is known to be null return null; } ResolvedJavaType contextType = invoke.getContextType(); if (receiverStamp.type() != null) { // the invoke target might be more specific than the holder (happens after inlining: // parameters lose their declared type...) ResolvedJavaType receiverType = receiverStamp.type(); if (receiverType != null && holder.isAssignableFrom(receiverType)) { holder = receiverType; if (receiverStamp.isExactType()) { assert targetMethod.getDeclaringClass().isAssignableFrom(holder) : holder + " subtype of " + targetMethod.getDeclaringClass() + " for " + targetMethod; ResolvedJavaMethod resolvedMethod = holder.resolveConcreteMethod(targetMethod, contextType); if (resolvedMethod != null) { return getExactInlineInfo(invoke, resolvedMethod); } } } } if (holder.isArray()) { // arrays can be treated as Objects ResolvedJavaMethod resolvedMethod = holder.resolveConcreteMethod(targetMethod, contextType); if (resolvedMethod != null) { return getExactInlineInfo(invoke, resolvedMethod); } } if (assumptions.useOptimisticAssumptions()) { ResolvedJavaType uniqueSubtype = holder.findUniqueConcreteSubtype(); if (uniqueSubtype != null) { ResolvedJavaMethod resolvedMethod = uniqueSubtype.resolveConcreteMethod(targetMethod, contextType); if (resolvedMethod != null) { return getAssumptionInlineInfo(invoke, resolvedMethod, new Assumptions.ConcreteSubtype(holder, uniqueSubtype)); } } ResolvedJavaMethod concrete = holder.findUniqueConcreteMethod(targetMethod); if (concrete != null) { return getAssumptionInlineInfo(invoke, concrete, new Assumptions.ConcreteMethod(targetMethod, holder, concrete)); } } // type check based inlining return getTypeCheckedInlineInfo(invoke, targetMethod); } private InlineInfo getTypeCheckedInlineInfo(Invoke invoke, ResolvedJavaMethod targetMethod) { JavaTypeProfile typeProfile; ValueNode receiver = invoke.callTarget().arguments().get(0); if (receiver instanceof TypeProfileProxyNode) { TypeProfileProxyNode typeProfileProxyNode = (TypeProfileProxyNode) receiver; typeProfile = typeProfileProxyNode.getProfile(); } else { InliningUtil.logNotInlined(invoke, inliningDepth(), targetMethod, "no type profile exists"); return null; } JavaTypeProfile.ProfiledType[] ptypes = typeProfile.getTypes(); if (ptypes == null || ptypes.length <= 0) { InliningUtil.logNotInlined(invoke, inliningDepth(), targetMethod, "no types in profile"); return null; } ResolvedJavaType contextType = invoke.getContextType(); double notRecordedTypeProbability = typeProfile.getNotRecordedProbability(); final OptimisticOptimizations optimisticOpts = context.getOptimisticOptimizations(); if (ptypes.length == 1 && notRecordedTypeProbability == 0) { if (!optimisticOpts.inlineMonomorphicCalls()) { InliningUtil.logNotInlined(invoke, inliningDepth(), targetMethod, "inlining monomorphic calls is disabled"); return null; } ResolvedJavaType type = ptypes[0].getType(); assert type.isArray() || !type.isAbstract(); ResolvedJavaMethod concrete = type.resolveConcreteMethod(targetMethod, contextType); if (!checkTargetConditions(invoke, concrete)) { return null; } return new TypeGuardInlineInfo(invoke, concrete, type); } else { invoke.setPolymorphic(true); if (!optimisticOpts.inlinePolymorphicCalls() && notRecordedTypeProbability == 0) { InliningUtil.logNotInlinedInvoke(invoke, inliningDepth(), targetMethod, "inlining polymorphic calls is disabled (%d types)", ptypes.length); return null; } if (!optimisticOpts.inlineMegamorphicCalls() && notRecordedTypeProbability > 0) { // due to filtering impossible types, notRecordedTypeProbability can be > 0 although // the number of types is lower than what can be recorded in a type profile InliningUtil.logNotInlinedInvoke(invoke, inliningDepth(), targetMethod, "inlining megamorphic calls is disabled (%d types, %f %% not recorded types)", ptypes.length, notRecordedTypeProbability * 100); return null; } // Find unique methods and their probabilities. ArrayList<ResolvedJavaMethod> concreteMethods = new ArrayList<>(); ArrayList<Double> concreteMethodsProbabilities = new ArrayList<>(); for (int i = 0; i < ptypes.length; i++) { ResolvedJavaMethod concrete = ptypes[i].getType().resolveConcreteMethod(targetMethod, contextType); if (concrete == null) { InliningUtil.logNotInlined(invoke, inliningDepth(), targetMethod, "could not resolve method"); return null; } int index = concreteMethods.indexOf(concrete); double curProbability = ptypes[i].getProbability(); if (index < 0) { index = concreteMethods.size(); concreteMethods.add(concrete); concreteMethodsProbabilities.add(curProbability); } else { concreteMethodsProbabilities.set(index, concreteMethodsProbabilities.get(index) + curProbability); } } // Clear methods that fall below the threshold. if (notRecordedTypeProbability > 0) { ArrayList<ResolvedJavaMethod> newConcreteMethods = new ArrayList<>(); ArrayList<Double> newConcreteMethodsProbabilities = new ArrayList<>(); for (int i = 0; i < concreteMethods.size(); ++i) { if (concreteMethodsProbabilities.get(i) >= MegamorphicInliningMinMethodProbability.getValue()) { newConcreteMethods.add(concreteMethods.get(i)); newConcreteMethodsProbabilities.add(concreteMethodsProbabilities.get(i)); } } if (newConcreteMethods.isEmpty()) { // No method left that is worth inlining. InliningUtil.logNotInlinedInvoke(invoke, inliningDepth(), targetMethod, "no methods remaining after filtering less frequent methods (%d methods previously)", concreteMethods.size()); return null; } concreteMethods = newConcreteMethods; concreteMethodsProbabilities = newConcreteMethodsProbabilities; } if (concreteMethods.size() > maxMethodPerInlining) { InliningUtil.logNotInlinedInvoke(invoke, inliningDepth(), targetMethod, "polymorphic call with more than %d target methods", maxMethodPerInlining); return null; } // Clean out types whose methods are no longer available. ArrayList<JavaTypeProfile.ProfiledType> usedTypes = new ArrayList<>(); ArrayList<Integer> typesToConcretes = new ArrayList<>(); for (JavaTypeProfile.ProfiledType type : ptypes) { ResolvedJavaMethod concrete = type.getType().resolveConcreteMethod(targetMethod, contextType); int index = concreteMethods.indexOf(concrete); if (index == -1) { notRecordedTypeProbability += type.getProbability(); } else { assert type.getType().isArray() || !type.getType().isAbstract() : type + " " + concrete; usedTypes.add(type); typesToConcretes.add(index); } } if (usedTypes.isEmpty()) { // No type left that is worth checking for. InliningUtil.logNotInlinedInvoke(invoke, inliningDepth(), targetMethod, "no types remaining after filtering less frequent types (%d types previously)", ptypes.length); return null; } for (ResolvedJavaMethod concrete : concreteMethods) { if (!checkTargetConditions(invoke, concrete)) { InliningUtil.logNotInlined(invoke, inliningDepth(), targetMethod, "it is a polymorphic method call and at least one invoked method cannot be inlined"); return null; } } return new MultiTypeGuardInlineInfo(invoke, concreteMethods, concreteMethodsProbabilities, usedTypes, typesToConcretes, notRecordedTypeProbability); } } private InlineInfo getAssumptionInlineInfo(Invoke invoke, ResolvedJavaMethod concrete, Assumptions.Assumption takenAssumption) { assert !concrete.isAbstract(); if (!checkTargetConditions(invoke, concrete)) { return null; } return new AssumptionInlineInfo(invoke, concrete, takenAssumption); } private InlineInfo getExactInlineInfo(Invoke invoke, ResolvedJavaMethod targetMethod) { assert !targetMethod.isAbstract(); if (!checkTargetConditions(invoke, targetMethod)) { return null; } return new ExactInlineInfo(invoke, targetMethod); } private void doInline(CallsiteHolderExplorable callerCallsiteHolder, MethodInvocation calleeInvocation, Assumptions callerAssumptions) { StructuredGraph callerGraph = callerCallsiteHolder.graph(); InlineInfo calleeInfo = calleeInvocation.callee(); try { try (Debug.Scope scope = Debug.scope("doInline", callerGraph)) { Set<Node> canonicalizedNodes = new HashSet<>(); calleeInfo.invoke().asNode().usages().snapshotTo(canonicalizedNodes); Collection<Node> parameterUsages = calleeInfo.inline(new Providers(context), callerAssumptions); canonicalizedNodes.addAll(parameterUsages); callerAssumptions.record(calleeInvocation.assumptions()); metricInliningRuns.increment(); Debug.dump(callerGraph, "after %s", calleeInfo); if (OptCanonicalizer.getValue()) { Graph.Mark markBeforeCanonicalization = callerGraph.getMark(); canonicalizer.applyIncremental(callerGraph, context, canonicalizedNodes); // process invokes that are possibly created during canonicalization for (Node newNode : callerGraph.getNewNodes(markBeforeCanonicalization)) { if (newNode instanceof Invoke) { callerCallsiteHolder.pushInvoke((Invoke) newNode); } } } callerCallsiteHolder.computeProbabilities(); metricInliningPerformed.increment(); } } catch (BailoutException bailout) { throw bailout; } catch (AssertionError | RuntimeException e) { throw new GraalInternalError(e).addContext(calleeInfo.toString()); } catch (GraalInternalError e) { throw e.addContext(calleeInfo.toString()); } catch (Throwable e) { throw Debug.handle(e); } } /** * * This method attempts: * <ol> * <li> * to inline at the callsite given by <code>calleeInvocation</code>, where that callsite belongs * to the {@link CallsiteHolderExplorable} at the top of the {@link #graphQueue} maintained in * this class.</li> * <li> * otherwise, to devirtualize the callsite in question.</li> * </ol> * * @return true iff inlining was actually performed */ private boolean tryToInline(MethodInvocation calleeInvocation, MethodInvocation parentInvocation, int inliningDepth) { CallsiteHolderExplorable callerCallsiteHolder = (CallsiteHolderExplorable) currentGraph(); InlineInfo calleeInfo = calleeInvocation.callee(); assert callerCallsiteHolder.containsInvoke(calleeInfo.invoke()); Assumptions callerAssumptions = parentInvocation.assumptions(); metricInliningConsidered.increment(); if (inliningPolicy.isWorthInlining(context.getReplacements(), calleeInvocation, inliningDepth, true)) { doInline(callerCallsiteHolder, calleeInvocation, callerAssumptions); return true; } if (context.getOptimisticOptimizations().devirtualizeInvokes()) { calleeInfo.tryToDevirtualizeInvoke(context.getMetaAccess(), callerAssumptions); } return false; } /** * This method picks one of the callsites belonging to the current * {@link CallsiteHolderExplorable}. Provided the callsite qualifies to be analyzed for * inlining, this method prepares a new stack top in {@link InliningData} for such callsite, * which comprises: * <ul> * <li>preparing a summary of feasible targets, ie preparing an {@link InlineInfo}</li> * <li>based on it, preparing the stack top proper which consists of:</li> * <ul> * <li>one {@link MethodInvocation}</li> * <li>a {@link CallsiteHolder} for each feasible target</li> * </ul> * </ul> * * <p> * The thus prepared "stack top" is needed by {@link #moveForward()} to explore the space of * inlining decisions (each decision one of: backtracking, delving, inlining). * </p> * * <p> * The {@link InlineInfo} used to get things rolling is kept around in the * {@link MethodInvocation}, it will be needed in case of inlining, see * {@link InlineInfo#inline(Providers, Assumptions)} * </p> */ private void processNextInvoke() { CallsiteHolderExplorable callsiteHolder = (CallsiteHolderExplorable) currentGraph(); Invoke invoke = callsiteHolder.popInvoke(); MethodInvocation callerInvocation = currentInvocation(); Assumptions parentAssumptions = callerInvocation.assumptions(); InlineInfo info = getInlineInfo(invoke, parentAssumptions); if (info != null) { Assumptions calleeAssumptions = new Assumptions(parentAssumptions.useOptimisticAssumptions()); info.populateInlinableElements(context, calleeAssumptions, canonicalizer); double invokeProbability = callsiteHolder.invokeProbability(invoke); double invokeRelevance = callsiteHolder.invokeRelevance(invoke); MethodInvocation methodInvocation = new MethodInvocation(info, calleeAssumptions, invokeProbability, invokeRelevance, freshlyInstantiatedArguments(invoke, callsiteHolder.getFixedParams())); pushInvocationAndGraphs(methodInvocation); } } /** * Gets the freshly instantiated arguments. * <p> * A freshly instantiated argument is either: * <uL> * <li>an {@link InliningData#isFreshInstantiation(com.oracle.graal.nodes.ValueNode)}</li> * <li>a fixed-param, ie a {@link ParameterNode} receiving a freshly instantiated argument</li> * </uL> * </p> * * @return the positions of freshly instantiated arguments in the argument list of the * <code>invoke</code>, or null if no such positions exist. */ public static BitSet freshlyInstantiatedArguments(Invoke invoke, Set<ParameterNode> fixedParams) { assert fixedParams != null; assert paramsAndInvokeAreInSameGraph(invoke, fixedParams); BitSet result = null; int argIdx = 0; for (ValueNode arg : invoke.callTarget().arguments()) { assert arg != null; if (isFreshInstantiation(arg) || fixedParams.contains(arg)) { if (result == null) { result = new BitSet(); } result.set(argIdx); } argIdx++; } return result; } private static boolean paramsAndInvokeAreInSameGraph(Invoke invoke, Set<ParameterNode> fixedParams) { if (fixedParams.isEmpty()) { return true; } for (ParameterNode p : fixedParams) { if (p.graph() != invoke.asNode().graph()) { return false; } } return true; } public int graphCount() { return graphQueue.size(); } public boolean hasUnprocessedGraphs() { return !graphQueue.isEmpty(); } private CallsiteHolder currentGraph() { return graphQueue.peek(); } private void popGraph() { graphQueue.pop(); assert graphQueue.size() <= maxGraphs; } private void popGraphs(int count) { assert count >= 0; for (int i = 0; i < count; i++) { graphQueue.pop(); } } private static final Object[] NO_CONTEXT = {}; /** * Gets the call hierarchy of this inlining from outer most call to inner most callee. */ private Object[] inliningContext() { if (!Debug.isDumpEnabled()) { return NO_CONTEXT; } Object[] result = new Object[graphQueue.size()]; int i = 0; for (CallsiteHolder g : graphQueue) { result[i++] = g.method(); } return result; } private MethodInvocation currentInvocation() { return invocationQueue.peekFirst(); } private void pushInvocationAndGraphs(MethodInvocation methodInvocation) { invocationQueue.addFirst(methodInvocation); InlineInfo info = methodInvocation.callee(); maxGraphs += info.numberOfMethods(); assert graphQueue.size() <= maxGraphs; for (int i = 0; i < info.numberOfMethods(); i++) { CallsiteHolder ch = methodInvocation.buildCallsiteHolderForElement(i); assert (ch == DUMMY_CALLSITE_HOLDER) || !contains(ch.graph()); graphQueue.push(ch); assert graphQueue.size() <= maxGraphs; } } private void popInvocation() { maxGraphs -= invocationQueue.peekFirst().callee().numberOfMethods(); assert graphQueue.size() <= maxGraphs; invocationQueue.removeFirst(); } public int countRecursiveInlining(ResolvedJavaMethod method) { int count = 0; for (CallsiteHolder callsiteHolder : graphQueue) { if (method.equals(callsiteHolder.method())) { count++; } } return count; } public int inliningDepth() { assert invocationQueue.size() > 0; return invocationQueue.size() - 1; } @Override public String toString() { StringBuilder result = new StringBuilder("Invocations: "); for (MethodInvocation invocation : invocationQueue) { if (invocation.callee() != null) { result.append(invocation.callee().numberOfMethods()); result.append("x "); result.append(invocation.callee().invoke()); result.append("; "); } } result.append("\nGraphs: "); for (CallsiteHolder graph : graphQueue) { result.append(graph.graph()); result.append("; "); } return result.toString(); } private boolean contains(StructuredGraph graph) { assert graph != null; for (CallsiteHolder info : graphQueue) { if (info.graph() == graph) { return true; } } return false; } /** * <p> * The stack realized by {@link InliningData} grows and shrinks as choices are made among the * alternatives below: * <ol> * <li> * not worth inlining: pop stack top, which comprises: * <ul> * <li>pop any remaining graphs not yet delved into</li> * <li>pop the current invocation</li> * </ul> * </li> * <li> * {@link #processNextInvoke() delve} into one of the callsites hosted in the current graph, * such callsite is explored next by {@link #moveForward()}</li> * <li> * {@link #tryToInline(MethodInvocation, MethodInvocation, int) try to inline}: move past the * current graph (remove it from the topmost element). * <ul> * <li> * If that was the last one then {@link #tryToInline(MethodInvocation, MethodInvocation, int) * try to inline} the callsite under consideration (ie, the "current invocation").</li> * <li> * Whether inlining occurs or not, that callsite is removed from the top of {@link InliningData} * .</li> * </ul> * </li> * </ol> * </p> * * <p> * Some facts about the alternatives above: * <ul> * <li> * the first step amounts to backtracking, the 2nd one to depth-search, and the 3rd one also * involves backtracking (however possibly after inlining).</li> * <li> * the choice of abandon-and-backtrack or delve-into depends on * {@link InliningPolicy#isWorthInlining} and {@link InliningPolicy#continueInlining}.</li> * <li> * the 3rd choice is picked whenever none of the previous choices are made</li> * </ul> * </p> * * @return true iff inlining was actually performed */ public boolean moveForward() { final MethodInvocation currentInvocation = currentInvocation(); final boolean backtrack = (!currentInvocation.isRoot() && !inliningPolicy.isWorthInlining(context.getReplacements(), currentInvocation, inliningDepth(), false)); if (backtrack) { int remainingGraphs = currentInvocation.totalGraphs() - currentInvocation.processedGraphs(); assert remainingGraphs > 0; popGraphs(remainingGraphs); popInvocation(); return false; } final boolean delve = currentGraph().hasRemainingInvokes() && inliningPolicy.continueInlining(currentGraph().graph()); if (delve) { processNextInvoke(); return false; } popGraph(); if (currentInvocation.isRoot()) { return false; } // try to inline assert currentInvocation.callee().invoke().asNode().isAlive(); currentInvocation.incrementProcessedGraphs(); if (currentInvocation.processedGraphs() == currentInvocation.totalGraphs()) { /* * "all of currentInvocation's graphs processed" amounts to * "all concrete methods that come into question already had the callees they contain analyzed for inlining" */ popInvocation(); final MethodInvocation parentInvoke = currentInvocation(); try (Debug.Scope s = Debug.scope("Inlining", inliningContext())) { return tryToInline(currentInvocation, parentInvoke, inliningDepth() + 1); } catch (Throwable e) { throw Debug.handle(e); } } return false; } /** * Checks an invariant that {@link #moveForward()} must maintain: "the top invocation records * how many concrete target methods (for it) remain on the {@link #graphQueue}; those targets * 'belong' to the current invocation in question. */ private boolean topGraphsForTopInvocation() { if (invocationQueue.isEmpty()) { assert graphQueue.isEmpty(); return true; } if (currentInvocation().isRoot()) { if (!graphQueue.isEmpty()) { assert graphQueue.size() == 1; } return true; } final int remainingGraphs = currentInvocation().totalGraphs() - currentInvocation().processedGraphs(); final Iterator<CallsiteHolder> iter = graphQueue.iterator(); for (int i = (remainingGraphs - 1); i >= 0; i--) { if (!iter.hasNext()) { assert false; return false; } CallsiteHolder queuedTargetCH = iter.next(); Inlineable targetIE = currentInvocation().callee().inlineableElementAt(i); if (targetIE instanceof InlineableMacroNode) { assert queuedTargetCH == DUMMY_CALLSITE_HOLDER; } else { InlineableGraph targetIG = (InlineableGraph) targetIE; assert queuedTargetCH.method().equals(targetIG.getGraph().method()); } } return true; } /** * This method checks invariants for this class. Named after shorthand for * "internal representation is ok". */ public boolean repOK() { assert topGraphsForTopInvocation(); return true; } }