--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/util/GraphUtil.java Thu Feb 16 15:46:09 2017 -0800
@@ -0,0 +1,904 @@
+/*
+ * Copyright (c) 2011, 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package org.graalvm.compiler.nodes.util;
+
+import static org.graalvm.compiler.graph.Graph.Options.VerifyGraalGraphEdges;
+import static org.graalvm.compiler.nodes.util.GraphUtil.Options.VerifyKillCFGUnusedNodes;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Iterator;
+import java.util.Set;
+
+import org.graalvm.compiler.bytecode.Bytecode;
+import org.graalvm.compiler.code.SourceStackTraceBailoutException;
+import org.graalvm.compiler.core.common.CollectionsFactory;
+import org.graalvm.compiler.core.common.spi.ConstantFieldProvider;
+import org.graalvm.compiler.core.common.type.StampFactory;
+import org.graalvm.compiler.debug.Debug;
+import org.graalvm.compiler.graph.Graph;
+import org.graalvm.compiler.graph.Node;
+import org.graalvm.compiler.graph.NodeClass;
+import org.graalvm.compiler.graph.NodeWorkList;
+import org.graalvm.compiler.graph.Position;
+import org.graalvm.compiler.graph.iterators.NodeIterable;
+import org.graalvm.compiler.graph.spi.SimplifierTool;
+import org.graalvm.compiler.nodeinfo.InputType;
+import org.graalvm.compiler.nodeinfo.NodeInfo;
+import org.graalvm.compiler.nodes.AbstractBeginNode;
+import org.graalvm.compiler.nodes.AbstractEndNode;
+import org.graalvm.compiler.nodes.AbstractMergeNode;
+import org.graalvm.compiler.nodes.FixedNode;
+import org.graalvm.compiler.nodes.FixedWithNextNode;
+import org.graalvm.compiler.nodes.FrameState;
+import org.graalvm.compiler.nodes.LoopBeginNode;
+import org.graalvm.compiler.nodes.LoopEndNode;
+import org.graalvm.compiler.nodes.LoopExitNode;
+import org.graalvm.compiler.nodes.PhiNode;
+import org.graalvm.compiler.nodes.ProxyNode;
+import org.graalvm.compiler.nodes.StateSplit;
+import org.graalvm.compiler.nodes.StructuredGraph;
+import org.graalvm.compiler.nodes.ValueNode;
+import org.graalvm.compiler.nodes.calc.FloatingNode;
+import org.graalvm.compiler.nodes.java.MethodCallTargetNode;
+import org.graalvm.compiler.nodes.spi.ArrayLengthProvider;
+import org.graalvm.compiler.nodes.spi.LimitedValueProxy;
+import org.graalvm.compiler.nodes.spi.LoweringProvider;
+import org.graalvm.compiler.nodes.spi.ValueProxy;
+import org.graalvm.compiler.options.Option;
+import org.graalvm.compiler.options.OptionType;
+import org.graalvm.compiler.options.OptionValue;
+
+import jdk.vm.ci.code.BailoutException;
+import jdk.vm.ci.code.BytecodePosition;
+import jdk.vm.ci.meta.Assumptions;
+import jdk.vm.ci.meta.Constant;
+import jdk.vm.ci.meta.ConstantReflectionProvider;
+import jdk.vm.ci.meta.MetaAccessProvider;
+import jdk.vm.ci.meta.ResolvedJavaMethod;
+
+public class GraphUtil {
+
+ public static class Options {
+ @Option(help = "Verify that there are no new unused nodes when performing killCFG", type = OptionType.Debug)//
+ public static final OptionValue<Boolean> VerifyKillCFGUnusedNodes = new OptionValue<>(false);
+ }
+
+ @SuppressWarnings("try")
+ public static void killCFG(FixedNode node, SimplifierTool tool) {
+ try (Debug.Scope scope = Debug.scope("KillCFG", node)) {
+ Set<Node> unusedNodes = null;
+ Set<Node> unsafeNodes = null;
+ Graph.NodeEventScope nodeEventScope = null;
+ if (VerifyGraalGraphEdges.getValue()) {
+ unsafeNodes = collectUnsafeNodes(node.graph());
+ }
+ if (VerifyKillCFGUnusedNodes.getValue()) {
+ Set<Node> collectedUnusedNodes = unusedNodes = CollectionsFactory.newSet();
+ nodeEventScope = node.graph().trackNodeEvents(new Graph.NodeEventListener() {
+ @Override
+ public void event(Graph.NodeEvent e, Node n) {
+ if (e == Graph.NodeEvent.ZERO_USAGES && isFloatingNode(n)) {
+ collectedUnusedNodes.add(n);
+ }
+ }
+ });
+ }
+ Debug.dump(Debug.VERY_DETAILED_LOG_LEVEL, node.graph(), "Before killCFG %s", node);
+ NodeWorkList worklist = killCFG(node, tool, null);
+ if (worklist != null) {
+ for (Node n : worklist) {
+ killCFG(n, tool, worklist);
+ }
+ }
+ if (VerifyGraalGraphEdges.getValue()) {
+ Set<Node> newUnsafeNodes = collectUnsafeNodes(node.graph());
+ newUnsafeNodes.removeAll(unsafeNodes);
+ assert newUnsafeNodes.isEmpty() : "New unsafe nodes: " + newUnsafeNodes;
+ }
+ if (VerifyKillCFGUnusedNodes.getValue()) {
+ nodeEventScope.close();
+ unusedNodes.removeIf(n -> n.isDeleted());
+ assert unusedNodes.isEmpty() : "New unused nodes: " + unusedNodes;
+ }
+ } catch (Throwable t) {
+ throw Debug.handle(t);
+ }
+ }
+
+ /**
+ * Collects all node in the graph which have non-optional inputs that are null.
+ */
+ private static Set<Node> collectUnsafeNodes(Graph graph) {
+ Set<Node> unsafeNodes = CollectionsFactory.newSet();
+ for (Node n : graph.getNodes()) {
+ for (Position pos : n.inputPositions()) {
+ Node input = pos.get(n);
+ if (input == null) {
+ if (!pos.isInputOptional()) {
+ unsafeNodes.add(n);
+ }
+ }
+ }
+ }
+ return unsafeNodes;
+ }
+
+ private static NodeWorkList killCFG(Node node, SimplifierTool tool, NodeWorkList worklist) {
+ NodeWorkList newWorklist = worklist;
+ if (node instanceof FixedNode) {
+ newWorklist = killCFGLinear((FixedNode) node, newWorklist, tool);
+ } else {
+ newWorklist = propagateKill(node, newWorklist);
+ Debug.dump(Debug.VERY_DETAILED_LOG_LEVEL, node.graph(), "killCFG (Floating) %s", node);
+ }
+ return newWorklist;
+ }
+
+ private static NodeWorkList killCFGLinear(FixedNode in, NodeWorkList worklist, SimplifierTool tool) {
+ NodeWorkList newWorklist = worklist;
+ FixedNode current = in;
+ while (current != null) {
+ FixedNode next = null;
+ assert current.isAlive();
+ if (current instanceof AbstractEndNode) {
+ // We reached a control flow end.
+ AbstractEndNode end = (AbstractEndNode) current;
+ newWorklist = killEnd(end, newWorklist, tool);
+ } else if (current instanceof FixedWithNextNode) {
+ // Node guaranteed to have a single successor
+ FixedWithNextNode fixedWithNext = (FixedWithNextNode) current;
+ assert fixedWithNext.successors().count() == 1 || fixedWithNext.successors().count() == 0;
+ assert fixedWithNext.successors().first() == fixedWithNext.next();
+ next = fixedWithNext.next();
+ } else {
+ /*
+ * We do not take a successor snapshot because this iterator supports concurrent
+ * modifications as long as they do not change the size of the successor list. Not
+ * taking a snapshot allows us to see modifications to other branches that may
+ * happen while processing one branch.
+ */
+ Iterator<Node> successors = current.successors().iterator();
+ if (successors.hasNext()) {
+ Node first = successors.next();
+ if (!successors.hasNext()) {
+ next = (FixedNode) first;
+ } else {
+ if (newWorklist == null) {
+ newWorklist = in.graph().createNodeWorkList();
+ }
+ for (Node successor : current.successors()) {
+ newWorklist.add(successor);
+ if (successor instanceof LoopExitNode) {
+ LoopExitNode exit = (LoopExitNode) successor;
+ exit.replaceFirstInput(exit.loopBegin(), null);
+ }
+ }
+ }
+ }
+ }
+ current.replaceAtPredecessor(null);
+ newWorklist = propagateKill(current, newWorklist);
+ Debug.dump(Debug.VERY_DETAILED_LOG_LEVEL, current.graph(), "killCFGLinear %s", current);
+ current = next;
+ }
+ Debug.dump(Debug.DETAILED_LOG_LEVEL, in.graph(), "killCFGLinear %s", in);
+ return newWorklist;
+ }
+
+ public static void killCFG(FixedNode node) {
+ killCFG(node, null);
+ }
+
+ /**
+ * Node type used temporarily while deleting loops.
+ *
+ * It is used as replacement for the loop {@link PhiNode PhiNodes} in order to break data-flow
+ * cycles before deleting the loop. The control-flow of the whole loop is killed before killing
+ * the poison node if they are still alive.
+ */
+ @NodeInfo(allowedUsageTypes = InputType.Unchecked)
+ private static final class PoisonNode extends FloatingNode {
+ public static final NodeClass<PoisonNode> TYPE = NodeClass.create(PoisonNode.class);
+
+ protected PoisonNode() {
+ super(TYPE, StampFactory.forVoid());
+ }
+ }
+
+ private static NodeWorkList killEnd(AbstractEndNode end, NodeWorkList worklist, SimplifierTool tool) {
+ NodeWorkList newWorklist = worklist;
+ AbstractMergeNode merge = end.merge();
+ if (merge != null) {
+ merge.removeEnd(end);
+ StructuredGraph graph = end.graph();
+ if (merge instanceof LoopBeginNode && merge.forwardEndCount() == 0) {
+ // dead loop
+ LoopBeginNode begin = (LoopBeginNode) merge;
+ // disconnect and delete loop ends & loop exits
+ for (LoopEndNode loopend : begin.loopEnds().snapshot()) {
+ loopend.predecessor().replaceFirstSuccessor(loopend, null);
+ loopend.safeDelete();
+ }
+ // clean unused proxies to avoid creating new unused nodes
+ for (LoopExitNode exit : begin.loopExits()) {
+ for (ProxyNode vpn : exit.proxies().snapshot()) {
+ tryKillUnused(vpn);
+ }
+ }
+ begin.removeExits();
+ PoisonNode poison = null;
+ if (merge.phis().isNotEmpty()) {
+ poison = graph.unique(new PoisonNode());
+ for (PhiNode phi : merge.phis()) {
+ phi.replaceAtUsages(poison);
+ }
+ for (PhiNode phi : merge.phis().snapshot()) {
+ killWithUnusedFloatingInputs(phi);
+ }
+ }
+ FixedNode loopBody = begin.next();
+ Debug.dump(Debug.VERY_DETAILED_LOG_LEVEL, end.graph(), "killEnd (Loop) %s after initial loop cleanup", end);
+ if (loopBody != null) {
+ // for small infinite loops, the body may already be killed while killing the
+ // LoopEnds
+ newWorklist = killCFG(loopBody, tool, worklist);
+ }
+ FrameState frameState = begin.stateAfter();
+ begin.safeDelete();
+ if (frameState != null) {
+ tryKillUnused(frameState);
+ }
+ if (poison != null && poison.isAlive()) {
+ if (newWorklist == null) {
+ newWorklist = graph.createNodeWorkList();
+ }
+ // drain the worklist to finish the loop before adding the poison
+ for (Node n : newWorklist) {
+ killCFG(n, tool, newWorklist);
+ }
+ if (poison.isAlive()) {
+ newWorklist.add(poison);
+ }
+ }
+ } else if (merge instanceof LoopBeginNode && ((LoopBeginNode) merge).loopEnds().isEmpty()) {
+ // not a loop anymore
+ if (tool != null) {
+ for (PhiNode phi : merge.phis()) {
+ tool.addToWorkList(phi.usages());
+ }
+ }
+ graph.reduceDegenerateLoopBegin((LoopBeginNode) merge);
+ } else if (merge.phiPredecessorCount() == 1) {
+ // not a merge anymore
+ if (tool != null) {
+ for (PhiNode phi : merge.phis()) {
+ tool.addToWorkList(phi.usages());
+ }
+ }
+ graph.reduceTrivialMerge(merge);
+ }
+ }
+ return newWorklist;
+ }
+
+ public static boolean isFloatingNode(Node n) {
+ return !(n instanceof FixedNode);
+ }
+
+ private static NodeWorkList propagateKill(Node node, NodeWorkList workList) {
+ NodeWorkList newWorkList = workList;
+ if (node != null && node.isAlive()) {
+ for (Node usage : node.usages().snapshot()) {
+ assert usage.isAlive();
+ if (isFloatingNode(usage)) {
+ boolean addUsage = false;
+ if (usage instanceof PhiNode) {
+ PhiNode phi = (PhiNode) usage;
+ assert phi.merge() != null;
+ if (phi.merge() == node) {
+ // we reach the phi directly through he merge, queue it.
+ addUsage = true;
+ } else {
+ // we reach it though a value
+ assert phi.values().contains(node);
+ // let that be handled when we reach the corresponding End node
+ }
+ } else {
+ addUsage = true;
+ }
+ if (addUsage) {
+ if (newWorkList == null) {
+ newWorkList = node.graph().createNodeWorkList();
+ }
+ newWorkList.add(usage);
+ }
+ }
+ usage.replaceFirstInput(node, null);
+ }
+ killWithUnusedFloatingInputs(node);
+ }
+ return newWorkList;
+ }
+
+ private static boolean checkKill(Node node) {
+ node.assertTrue(node.isAlive(), "must be alive");
+ node.assertTrue(node.hasNoUsages(), "cannot kill node %s because of usages: %s", node, node.usages());
+ node.assertTrue(node.predecessor() == null, "cannot kill node %s because of predecessor: %s", node, node.predecessor());
+ return true;
+ }
+
+ public static void killWithUnusedFloatingInputs(Node node) {
+ assert checkKill(node);
+ node.markDeleted();
+ outer: for (Node in : node.inputs()) {
+ if (in.isAlive()) {
+ in.removeUsage(node);
+ if (in.hasNoUsages()) {
+ node.maybeNotifyZeroUsages(in);
+ }
+ if (isFloatingNode(in)) {
+ if (in.hasNoUsages()) {
+ killWithUnusedFloatingInputs(in);
+ } else if (in instanceof PhiNode) {
+ for (Node use : in.usages()) {
+ if (use != in) {
+ continue outer;
+ }
+ }
+ in.replaceAtUsages(null);
+ killWithUnusedFloatingInputs(in);
+ }
+ }
+ }
+ }
+ }
+
+ /**
+ * Removes all nodes created after the {@code mark}, assuming no "old" nodes point to "new"
+ * nodes.
+ */
+ public static void removeNewNodes(Graph graph, Graph.Mark mark) {
+ assert checkNoOldToNewEdges(graph, mark);
+ for (Node n : graph.getNewNodes(mark)) {
+ n.markDeleted();
+ for (Node in : n.inputs()) {
+ in.removeUsage(n);
+ }
+ }
+ }
+
+ private static boolean checkNoOldToNewEdges(Graph graph, Graph.Mark mark) {
+ for (Node old : graph.getNodes()) {
+ if (graph.isNew(mark, old)) {
+ break;
+ }
+ for (Node n : old.successors()) {
+ assert !graph.isNew(mark, n) : old + " -> " + n;
+ }
+ for (Node n : old.inputs()) {
+ assert !graph.isNew(mark, n) : old + " -> " + n;
+ }
+ }
+ return true;
+ }
+
+ public static void removeFixedWithUnusedInputs(FixedWithNextNode fixed) {
+ if (fixed instanceof StateSplit) {
+ FrameState stateAfter = ((StateSplit) fixed).stateAfter();
+ if (stateAfter != null) {
+ ((StateSplit) fixed).setStateAfter(null);
+ if (stateAfter.hasNoUsages()) {
+ killWithUnusedFloatingInputs(stateAfter);
+ }
+ }
+ }
+ unlinkFixedNode(fixed);
+ killWithUnusedFloatingInputs(fixed);
+ }
+
+ public static void unlinkFixedNode(FixedWithNextNode fixed) {
+ assert fixed.next() != null && fixed.predecessor() != null && fixed.isAlive() : fixed;
+ FixedNode next = fixed.next();
+ fixed.setNext(null);
+ fixed.replaceAtPredecessor(next);
+ }
+
+ public static void checkRedundantPhi(PhiNode phiNode) {
+ if (phiNode.isDeleted() || phiNode.valueCount() == 1) {
+ return;
+ }
+
+ ValueNode singleValue = phiNode.singleValue();
+ if (singleValue != PhiNode.MULTIPLE_VALUES) {
+ Collection<PhiNode> phiUsages = phiNode.usages().filter(PhiNode.class).snapshot();
+ Collection<ProxyNode> proxyUsages = phiNode.usages().filter(ProxyNode.class).snapshot();
+ phiNode.replaceAtUsagesAndDelete(singleValue);
+ for (PhiNode phi : phiUsages) {
+ checkRedundantPhi(phi);
+ }
+ for (ProxyNode proxy : proxyUsages) {
+ checkRedundantProxy(proxy);
+ }
+ }
+ }
+
+ public static void checkRedundantProxy(ProxyNode vpn) {
+ if (vpn.isDeleted()) {
+ return;
+ }
+ AbstractBeginNode proxyPoint = vpn.proxyPoint();
+ if (proxyPoint instanceof LoopExitNode) {
+ LoopExitNode exit = (LoopExitNode) proxyPoint;
+ LoopBeginNode loopBegin = exit.loopBegin();
+ Node vpnValue = vpn.value();
+ for (ValueNode v : loopBegin.stateAfter().values()) {
+ ValueNode v2 = v;
+ if (loopBegin.isPhiAtMerge(v2)) {
+ v2 = ((PhiNode) v2).valueAt(loopBegin.forwardEnd());
+ }
+ if (vpnValue == v2) {
+ Collection<PhiNode> phiUsages = vpn.usages().filter(PhiNode.class).snapshot();
+ Collection<ProxyNode> proxyUsages = vpn.usages().filter(ProxyNode.class).snapshot();
+ vpn.replaceAtUsagesAndDelete(vpnValue);
+ for (PhiNode phi : phiUsages) {
+ checkRedundantPhi(phi);
+ }
+ for (ProxyNode proxy : proxyUsages) {
+ checkRedundantProxy(proxy);
+ }
+ return;
+ }
+ }
+ }
+ }
+
+ /**
+ * Remove loop header without loop ends. This can happen with degenerated loops like this one:
+ *
+ * <pre>
+ * for (;;) {
+ * try {
+ * break;
+ * } catch (UnresolvedException iioe) {
+ * }
+ * }
+ * </pre>
+ */
+ public static void normalizeLoops(StructuredGraph graph) {
+ boolean loopRemoved = false;
+ for (LoopBeginNode begin : graph.getNodes(LoopBeginNode.TYPE)) {
+ if (begin.loopEnds().isEmpty()) {
+ assert begin.forwardEndCount() == 1;
+ graph.reduceDegenerateLoopBegin(begin);
+ loopRemoved = true;
+ } else {
+ normalizeLoopBegin(begin);
+ }
+ }
+
+ if (loopRemoved) {
+ /*
+ * Removing a degenerated loop can make non-loop phi functions unnecessary. Therefore,
+ * we re-check all phi functions and remove redundant ones.
+ */
+ for (Node node : graph.getNodes()) {
+ if (node instanceof PhiNode) {
+ checkRedundantPhi((PhiNode) node);
+ }
+ }
+ }
+ }
+
+ private static void normalizeLoopBegin(LoopBeginNode begin) {
+ // Delete unnecessary loop phi functions, i.e., phi functions where all inputs are either
+ // the same or the phi itself.
+ for (PhiNode phi : begin.phis().snapshot()) {
+ GraphUtil.checkRedundantPhi(phi);
+ }
+ for (LoopExitNode exit : begin.loopExits()) {
+ for (ProxyNode vpn : exit.proxies().snapshot()) {
+ GraphUtil.checkRedundantProxy(vpn);
+ }
+ }
+ }
+
+ /**
+ * Gets an approximate source code location for a node if possible.
+ *
+ * @return the StackTraceElements if an approximate source location is found, null otherwise
+ */
+ public static StackTraceElement[] approxSourceStackTraceElement(Node node) {
+ ArrayList<StackTraceElement> elements = new ArrayList<>();
+ Node n = node;
+ while (n != null) {
+ if (n instanceof MethodCallTargetNode) {
+ elements.add(((MethodCallTargetNode) n).targetMethod().asStackTraceElement(-1));
+ n = ((MethodCallTargetNode) n).invoke().asNode();
+ }
+
+ if (n instanceof StateSplit) {
+ FrameState state = ((StateSplit) n).stateAfter();
+ elements.addAll(Arrays.asList(approxSourceStackTraceElement(state)));
+ break;
+ }
+ n = n.predecessor();
+ }
+ return elements.toArray(new StackTraceElement[elements.size()]);
+ }
+
+ /**
+ * Gets an approximate source code location for frame state.
+ *
+ * @return the StackTraceElements if an approximate source location is found, null otherwise
+ */
+ public static StackTraceElement[] approxSourceStackTraceElement(FrameState frameState) {
+ ArrayList<StackTraceElement> elements = new ArrayList<>();
+ FrameState state = frameState;
+ while (state != null) {
+ Bytecode code = state.getCode();
+ if (code != null) {
+ elements.add(code.asStackTraceElement(state.bci - 1));
+ }
+ state = state.outerFrameState();
+ }
+ return elements.toArray(new StackTraceElement[0]);
+ }
+
+ /**
+ * Gets approximate stack trace elements for a bytecode position.
+ */
+ public static StackTraceElement[] approxSourceStackTraceElement(BytecodePosition bytecodePosition) {
+ ArrayList<StackTraceElement> elements = new ArrayList<>();
+ BytecodePosition position = bytecodePosition;
+ while (position != null) {
+ ResolvedJavaMethod method = position.getMethod();
+ if (method != null) {
+ elements.add(method.asStackTraceElement(position.getBCI()));
+ }
+ position = position.getCaller();
+ }
+ return elements.toArray(new StackTraceElement[0]);
+ }
+
+ /**
+ * Gets an approximate source code location for a node, encoded as an exception, if possible.
+ *
+ * @return the exception with the location
+ */
+ public static RuntimeException approxSourceException(Node node, Throwable cause) {
+ final StackTraceElement[] elements = approxSourceStackTraceElement(node);
+ return createBailoutException(cause == null ? "" : cause.getMessage(), cause, elements);
+ }
+
+ /**
+ * Creates a bailout exception with the given stack trace elements and message.
+ *
+ * @param message the message of the exception
+ * @param elements the stack trace elements
+ * @return the exception
+ */
+ public static BailoutException createBailoutException(String message, Throwable cause, StackTraceElement[] elements) {
+ return SourceStackTraceBailoutException.create(cause, message, elements);
+ }
+
+ /**
+ * Gets an approximate source code location for a node if possible.
+ *
+ * @return a file name and source line number in stack trace format (e.g. "String.java:32") if
+ * an approximate source location is found, null otherwise
+ */
+ public static String approxSourceLocation(Node node) {
+ StackTraceElement[] stackTraceElements = approxSourceStackTraceElement(node);
+ if (stackTraceElements != null && stackTraceElements.length > 0) {
+ StackTraceElement top = stackTraceElements[0];
+ if (top.getFileName() != null && top.getLineNumber() >= 0) {
+ return top.getFileName() + ":" + top.getLineNumber();
+ }
+ }
+ return null;
+ }
+
+ /**
+ * Returns a string representation of the given collection of objects.
+ *
+ * @param objects The {@link Iterable} that will be used to iterate over the objects.
+ * @return A string of the format "[a, b, ...]".
+ */
+ public static String toString(Iterable<?> objects) {
+ StringBuilder str = new StringBuilder();
+ str.append("[");
+ for (Object o : objects) {
+ str.append(o).append(", ");
+ }
+ if (str.length() > 1) {
+ str.setLength(str.length() - 2);
+ }
+ str.append("]");
+ return str.toString();
+ }
+
+ /**
+ * Gets the original value by iterating through all {@link ValueProxy ValueProxies}.
+ *
+ * @param value The start value.
+ * @return The first non-proxy value encountered.
+ */
+ public static ValueNode unproxify(ValueNode value) {
+ ValueNode result = value;
+ while (result instanceof ValueProxy) {
+ result = ((ValueProxy) result).getOriginalNode();
+ }
+ return result;
+ }
+
+ /**
+ * Looks for an {@link ArrayLengthProvider} while iterating through all {@link ValueProxy
+ * ValueProxies}.
+ *
+ * @param value The start value.
+ * @return The array length if one was found, or null otherwise.
+ */
+ public static ValueNode arrayLength(ValueNode value) {
+ ValueNode current = value;
+ do {
+ if (current instanceof ArrayLengthProvider) {
+ ValueNode length = ((ArrayLengthProvider) current).length();
+ if (length != null) {
+ return length;
+ }
+ }
+ if (current instanceof ValueProxy) {
+ current = ((ValueProxy) current).getOriginalNode();
+ } else {
+ break;
+ }
+ } while (true);
+ return null;
+ }
+
+ /**
+ * Tries to find an original value of the given node by traversing through proxies and
+ * unambiguous phis. Note that this method will perform an exhaustive search through phis. It is
+ * intended to be used during graph building, when phi nodes aren't yet canonicalized.
+ *
+ * @param proxy The node whose original value should be determined.
+ */
+ public static ValueNode originalValue(ValueNode proxy) {
+ ValueNode v = proxy;
+ do {
+ if (v instanceof LimitedValueProxy) {
+ v = ((LimitedValueProxy) v).getOriginalNode();
+ } else if (v instanceof PhiNode) {
+ v = ((PhiNode) v).singleValue();
+ if (v == PhiNode.MULTIPLE_VALUES) {
+ v = null;
+ }
+ } else {
+ break;
+ }
+ } while (v != null);
+
+ if (v == null) {
+ v = new OriginalValueSearch(proxy).result;
+ }
+ return v;
+ }
+
+ public static boolean tryKillUnused(Node node) {
+ if (node.isAlive() && isFloatingNode(node) && node.hasNoUsages()) {
+ killWithUnusedFloatingInputs(node);
+ return true;
+ }
+ return false;
+ }
+
+ /**
+ * Exhaustive search for {@link GraphUtil#originalValue(ValueNode)} when a simple search fails.
+ * This can happen in the presence of complicated phi/proxy/phi constructs.
+ */
+ static class OriginalValueSearch {
+ ValueNode result;
+
+ OriginalValueSearch(ValueNode proxy) {
+ NodeWorkList worklist = proxy.graph().createNodeWorkList();
+ worklist.add(proxy);
+ for (Node node : worklist) {
+ if (node instanceof LimitedValueProxy) {
+ ValueNode originalValue = ((LimitedValueProxy) node).getOriginalNode();
+ if (!process(originalValue, worklist)) {
+ return;
+ }
+ } else if (node instanceof PhiNode) {
+ for (Node value : ((PhiNode) node).values()) {
+ if (!process((ValueNode) value, worklist)) {
+ return;
+ }
+ }
+ } else {
+ if (!process((ValueNode) node, null)) {
+ return;
+ }
+ }
+ }
+ }
+
+ /**
+ * Process a node as part of this search.
+ *
+ * @param node the next node encountered in the search
+ * @param worklist if non-null, {@code node} will be added to this list. Otherwise,
+ * {@code node} is treated as a candidate result.
+ * @return true if the search should continue, false if a definitive {@link #result} has
+ * been found
+ */
+ private boolean process(ValueNode node, NodeWorkList worklist) {
+ if (node.isAlive()) {
+ if (worklist == null) {
+ if (result == null) {
+ // Initial candidate result: continue search
+ result = node;
+ } else if (result != node) {
+ // Conflicts with existing candidate: stop search with null result
+ result = null;
+ return false;
+ }
+ } else {
+ worklist.add(node);
+ }
+ }
+ return true;
+ }
+ }
+
+ /**
+ * Returns an iterator that will return the given node followed by all its predecessors, up
+ * until the point where {@link Node#predecessor()} returns null.
+ *
+ * @param start the node at which to start iterating
+ */
+ public static NodeIterable<FixedNode> predecessorIterable(final FixedNode start) {
+ return new NodeIterable<FixedNode>() {
+ @Override
+ public Iterator<FixedNode> iterator() {
+ return new Iterator<FixedNode>() {
+ public FixedNode current = start;
+
+ @Override
+ public boolean hasNext() {
+ return current != null;
+ }
+
+ @Override
+ public FixedNode next() {
+ try {
+ return current;
+ } finally {
+ current = (FixedNode) current.predecessor();
+ }
+ }
+ };
+ }
+ };
+ }
+
+ private static final class DefaultSimplifierTool implements SimplifierTool {
+ private final MetaAccessProvider metaAccess;
+ private final ConstantReflectionProvider constantReflection;
+ private final ConstantFieldProvider constantFieldProvider;
+ private final boolean canonicalizeReads;
+ private final Assumptions assumptions;
+ private final LoweringProvider loweringProvider;
+
+ DefaultSimplifierTool(MetaAccessProvider metaAccess, ConstantReflectionProvider constantReflection, ConstantFieldProvider constantFieldProvider, boolean canonicalizeReads,
+ Assumptions assumptions, LoweringProvider loweringProvider) {
+ this.metaAccess = metaAccess;
+ this.constantReflection = constantReflection;
+ this.constantFieldProvider = constantFieldProvider;
+ this.canonicalizeReads = canonicalizeReads;
+ this.assumptions = assumptions;
+ this.loweringProvider = loweringProvider;
+ }
+
+ @Override
+ public MetaAccessProvider getMetaAccess() {
+ return metaAccess;
+ }
+
+ @Override
+ public ConstantReflectionProvider getConstantReflection() {
+ return constantReflection;
+ }
+
+ @Override
+ public ConstantFieldProvider getConstantFieldProvider() {
+ return constantFieldProvider;
+ }
+
+ @Override
+ public boolean canonicalizeReads() {
+ return canonicalizeReads;
+ }
+
+ @Override
+ public boolean allUsagesAvailable() {
+ return true;
+ }
+
+ @Override
+ public void deleteBranch(Node branch) {
+ FixedNode fixedBranch = (FixedNode) branch;
+ fixedBranch.predecessor().replaceFirstSuccessor(fixedBranch, null);
+ GraphUtil.killCFG(fixedBranch, this);
+ }
+
+ @Override
+ public void removeIfUnused(Node node) {
+ GraphUtil.tryKillUnused(node);
+ }
+
+ @Override
+ public void addToWorkList(Node node) {
+ }
+
+ @Override
+ public void addToWorkList(Iterable<? extends Node> nodes) {
+ }
+
+ @Override
+ public Assumptions getAssumptions() {
+ return assumptions;
+ }
+
+ @Override
+ public boolean supportSubwordCompare(int bits) {
+ if (loweringProvider != null) {
+ return loweringProvider.supportSubwordCompare(bits);
+ } else {
+ return false;
+ }
+ }
+ }
+
+ public static SimplifierTool getDefaultSimplifier(MetaAccessProvider metaAccess, ConstantReflectionProvider constantReflection, ConstantFieldProvider constantFieldProvider,
+ boolean canonicalizeReads, Assumptions assumptions) {
+ return getDefaultSimplifier(metaAccess, constantReflection, constantFieldProvider, canonicalizeReads, assumptions, null);
+ }
+
+ public static SimplifierTool getDefaultSimplifier(MetaAccessProvider metaAccess, ConstantReflectionProvider constantReflection, ConstantFieldProvider constantFieldProvider,
+ boolean canonicalizeReads, Assumptions assumptions, LoweringProvider loweringProvider) {
+ return new DefaultSimplifierTool(metaAccess, constantReflection, constantFieldProvider, canonicalizeReads, assumptions, loweringProvider);
+ }
+
+ public static Constant foldIfConstantAndRemove(ValueNode node, ValueNode constant) {
+ assert node.inputs().contains(constant);
+ if (constant.isConstant()) {
+ node.replaceFirstInput(constant, null);
+ Constant result = constant.asConstant();
+ tryKillUnused(constant);
+ return result;
+ }
+ return null;
+ }
+}