--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/util/GraphUtil.java Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,1025 @@
+/*
+ * 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 java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.List;
+import java.util.function.BiFunction;
+
+import org.graalvm.compiler.bytecode.Bytecode;
+import org.graalvm.compiler.code.SourceStackTraceBailoutException;
+import org.graalvm.compiler.core.common.spi.ConstantFieldProvider;
+import org.graalvm.compiler.core.common.type.ObjectStamp;
+import org.graalvm.compiler.debug.DebugContext;
+import org.graalvm.compiler.graph.Graph;
+import org.graalvm.compiler.graph.Node;
+import org.graalvm.compiler.graph.NodeBitMap;
+import org.graalvm.compiler.graph.NodeSourcePosition;
+import org.graalvm.compiler.graph.NodeStack;
+import org.graalvm.compiler.graph.Position;
+import org.graalvm.compiler.graph.iterators.NodeIterable;
+import org.graalvm.compiler.graph.spi.SimplifierTool;
+import org.graalvm.compiler.nodes.AbstractBeginNode;
+import org.graalvm.compiler.nodes.AbstractEndNode;
+import org.graalvm.compiler.nodes.AbstractMergeNode;
+import org.graalvm.compiler.nodes.ConstantNode;
+import org.graalvm.compiler.nodes.ControlSplitNode;
+import org.graalvm.compiler.nodes.FixedNode;
+import org.graalvm.compiler.nodes.FixedWithNextNode;
+import org.graalvm.compiler.nodes.FrameState;
+import org.graalvm.compiler.nodes.GuardNode;
+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.PiNode;
+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.java.LoadIndexedNode;
+import org.graalvm.compiler.nodes.java.MethodCallTargetNode;
+import org.graalvm.compiler.nodes.java.MonitorIdNode;
+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.nodes.spi.VirtualizerTool;
+import org.graalvm.compiler.nodes.virtual.VirtualArrayNode;
+import org.graalvm.compiler.nodes.virtual.VirtualObjectNode;
+import org.graalvm.compiler.options.Option;
+import org.graalvm.compiler.options.OptionKey;
+import org.graalvm.compiler.options.OptionType;
+import org.graalvm.compiler.options.OptionValues;
+import org.graalvm.util.EconomicMap;
+import org.graalvm.util.EconomicSet;
+import org.graalvm.util.Equivalence;
+import org.graalvm.util.MapCursor;
+
+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.JavaKind;
+import jdk.vm.ci.meta.MetaAccessProvider;
+import jdk.vm.ci.meta.ResolvedJavaMethod;
+import jdk.vm.ci.meta.ResolvedJavaType;
+
+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 OptionKey<Boolean> VerifyKillCFGUnusedNodes = new OptionKey<>(false);
+ }
+
+ private static void killCFGInner(FixedNode node) {
+ EconomicSet<Node> markedNodes = EconomicSet.create();
+ EconomicMap<AbstractMergeNode, List<AbstractEndNode>> unmarkedMerges = EconomicMap.create();
+
+ // Detach this node from CFG
+ node.replaceAtPredecessor(null);
+
+ markFixedNodes(node, markedNodes, unmarkedMerges);
+
+ fixSurvivingAffectedMerges(markedNodes, unmarkedMerges);
+
+ DebugContext debug = node.getDebug();
+ debug.dump(DebugContext.DETAILED_LEVEL, node.graph(), "After fixing merges (killCFG %s)", node);
+
+ // Mark non-fixed nodes
+ markUsages(markedNodes);
+
+ // Detach marked nodes from non-marked nodes
+ for (Node marked : markedNodes) {
+ for (Node input : marked.inputs()) {
+ if (!markedNodes.contains(input)) {
+ marked.replaceFirstInput(input, null);
+ tryKillUnused(input);
+ }
+ }
+ }
+ debug.dump(DebugContext.VERY_DETAILED_LEVEL, node.graph(), "After disconnecting non-marked inputs (killCFG %s)", node);
+ // Kill marked nodes
+ for (Node marked : markedNodes) {
+ if (marked.isAlive()) {
+ marked.markDeleted();
+ }
+ }
+ }
+
+ private static void markFixedNodes(FixedNode node, EconomicSet<Node> markedNodes, EconomicMap<AbstractMergeNode, List<AbstractEndNode>> unmarkedMerges) {
+ NodeStack workStack = new NodeStack();
+ workStack.push(node);
+ while (!workStack.isEmpty()) {
+ Node fixedNode = workStack.pop();
+ markedNodes.add(fixedNode);
+ if (fixedNode instanceof AbstractMergeNode) {
+ unmarkedMerges.removeKey((AbstractMergeNode) fixedNode);
+ }
+ while (fixedNode instanceof FixedWithNextNode) {
+ fixedNode = ((FixedWithNextNode) fixedNode).next();
+ if (fixedNode != null) {
+ markedNodes.add(fixedNode);
+ }
+ }
+ if (fixedNode instanceof ControlSplitNode) {
+ for (Node successor : fixedNode.successors()) {
+ workStack.push(successor);
+ }
+ } else if (fixedNode instanceof AbstractEndNode) {
+ AbstractEndNode end = (AbstractEndNode) fixedNode;
+ AbstractMergeNode merge = end.merge();
+ if (merge != null) {
+ assert !markedNodes.contains(merge) || (merge instanceof LoopBeginNode && end instanceof LoopEndNode) : merge;
+ if (merge instanceof LoopBeginNode) {
+ if (end == ((LoopBeginNode) merge).forwardEnd()) {
+ workStack.push(merge);
+ continue;
+ }
+ if (markedNodes.contains(merge)) {
+ continue;
+ }
+ }
+ List<AbstractEndNode> endsSeen = unmarkedMerges.get(merge);
+ if (endsSeen == null) {
+ endsSeen = new ArrayList<>(merge.forwardEndCount());
+ unmarkedMerges.put(merge, endsSeen);
+ }
+ endsSeen.add(end);
+ if (!(end instanceof LoopEndNode) && endsSeen.size() == merge.forwardEndCount()) {
+ assert merge.forwardEnds().filter(n -> !markedNodes.contains(n)).isEmpty();
+ // all this merge's forward ends are marked: it needs to be killed
+ workStack.push(merge);
+ }
+ }
+ }
+ }
+ }
+
+ private static void fixSurvivingAffectedMerges(EconomicSet<Node> markedNodes, EconomicMap<AbstractMergeNode, List<AbstractEndNode>> unmarkedMerges) {
+ MapCursor<AbstractMergeNode, List<AbstractEndNode>> cursor = unmarkedMerges.getEntries();
+ while (cursor.advance()) {
+ AbstractMergeNode merge = cursor.getKey();
+ for (AbstractEndNode end : cursor.getValue()) {
+ merge.removeEnd(end);
+ }
+ if (merge.phiPredecessorCount() == 1) {
+ if (merge instanceof LoopBeginNode) {
+ LoopBeginNode loopBegin = (LoopBeginNode) merge;
+ assert merge.forwardEndCount() == 1;
+ for (LoopExitNode loopExit : loopBegin.loopExits().snapshot()) {
+ if (markedNodes.contains(loopExit)) {
+ /*
+ * disconnect from loop begin so that reduceDegenerateLoopBegin doesn't
+ * transform it into a new beginNode
+ */
+ loopExit.replaceFirstInput(loopBegin, null);
+ }
+ }
+ merge.graph().reduceDegenerateLoopBegin(loopBegin);
+ } else {
+ merge.graph().reduceTrivialMerge(merge);
+ }
+ } else {
+ assert merge.phiPredecessorCount() > 1 : merge;
+ }
+ }
+ }
+
+ private static void markUsages(EconomicSet<Node> markedNodes) {
+ NodeStack workStack = new NodeStack(markedNodes.size() + 4);
+ for (Node marked : markedNodes) {
+ workStack.push(marked);
+ }
+ while (!workStack.isEmpty()) {
+ Node marked = workStack.pop();
+ for (Node usage : marked.usages()) {
+ if (!markedNodes.contains(usage)) {
+ workStack.push(usage);
+ markedNodes.add(usage);
+ }
+ }
+ }
+ }
+
+ @SuppressWarnings("try")
+ public static void killCFG(FixedNode node) {
+ DebugContext debug = node.getDebug();
+ try (DebugContext.Scope scope = debug.scope("KillCFG", node)) {
+ EconomicSet<Node> unusedNodes = null;
+ EconomicSet<Node> unsafeNodes = null;
+ Graph.NodeEventScope nodeEventScope = null;
+ OptionValues options = node.getOptions();
+ if (Graph.Options.VerifyGraalGraphEdges.getValue(options)) {
+ unsafeNodes = collectUnsafeNodes(node.graph());
+ }
+ if (GraphUtil.Options.VerifyKillCFGUnusedNodes.getValue(options)) {
+ EconomicSet<Node> collectedUnusedNodes = unusedNodes = EconomicSet.create(Equivalence.IDENTITY);
+ nodeEventScope = node.graph().trackNodeEvents(new Graph.NodeEventListener() {
+ @Override
+ public void event(Graph.NodeEvent e, Node n) {
+ if (e == Graph.NodeEvent.ZERO_USAGES && isFloatingNode(n) && !(n instanceof GuardNode)) {
+ collectedUnusedNodes.add(n);
+ }
+ }
+ });
+ }
+ debug.dump(DebugContext.VERY_DETAILED_LEVEL, node.graph(), "Before killCFG %s", node);
+ killCFGInner(node);
+ debug.dump(DebugContext.VERY_DETAILED_LEVEL, node.graph(), "After killCFG %s", node);
+ if (Graph.Options.VerifyGraalGraphEdges.getValue(options)) {
+ EconomicSet<Node> newUnsafeNodes = collectUnsafeNodes(node.graph());
+ newUnsafeNodes.removeAll(unsafeNodes);
+ assert newUnsafeNodes.isEmpty() : "New unsafe nodes: " + newUnsafeNodes;
+ }
+ if (GraphUtil.Options.VerifyKillCFGUnusedNodes.getValue(options)) {
+ nodeEventScope.close();
+ Iterator<Node> iterator = unusedNodes.iterator();
+ while (iterator.hasNext()) {
+ Node curNode = iterator.next();
+ if (curNode.isDeleted()) {
+ iterator.remove();
+ }
+ }
+ 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 EconomicSet<Node> collectUnsafeNodes(Graph graph) {
+ EconomicSet<Node> unsafeNodes = EconomicSet.create(Equivalence.IDENTITY);
+ 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;
+ }
+
+ public static boolean isFloatingNode(Node n) {
+ return !(n instanceof FixedNode);
+ }
+
+ private static boolean checkKill(Node node, boolean mayKillGuard) {
+ node.assertTrue(mayKillGuard || !(node instanceof GuardNode), "must not be a guard node %s", 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) {
+ killWithUnusedFloatingInputs(node, false);
+ }
+
+ public static void killWithUnusedFloatingInputs(Node node, boolean mayKillGuard) {
+ assert checkKill(node, mayKillGuard);
+ 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()) {
+ if (in instanceof GuardNode) {
+ // Guard nodes are only killed if their anchor dies.
+ } else {
+ 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.singleValueOrThis();
+ if (singleValue != phiNode) {
+ 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) {
+ NodeSourcePosition position = node.getNodeSourcePosition();
+ if (position != null) {
+ // use GraphBuilderConfiguration and enable trackNodeSourcePosition to get better source
+ // positions.
+ return approxSourceStackTraceElement(position);
+ }
+ 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) {
+ if (value instanceof ValueProxy) {
+ return unproxify((ValueProxy) value);
+ } else {
+ return value;
+ }
+ }
+
+ /**
+ * Gets the original value by iterating through all {@link ValueProxy ValueProxies}.
+ *
+ * @param value the start value proxy.
+ * @return the first non-proxy value encountered
+ */
+ public static ValueNode unproxify(ValueProxy value) {
+ if (value != null) {
+ ValueNode result = value.getOriginalNode();
+ while (result instanceof ValueProxy) {
+ result = ((ValueProxy) result).getOriginalNode();
+ }
+ return result;
+ } else {
+ return null;
+ }
+ }
+
+ public static ValueNode skipPi(ValueNode node) {
+ ValueNode n = node;
+ while (n instanceof PiNode) {
+ PiNode piNode = (PiNode) n;
+ n = piNode.getOriginalNode();
+ }
+ return n;
+ }
+
+ public static ValueNode skipPiWhileNonNull(ValueNode node) {
+ ValueNode n = node;
+ while (n instanceof PiNode) {
+ PiNode piNode = (PiNode) n;
+ ObjectStamp originalStamp = (ObjectStamp) piNode.getOriginalNode().stamp();
+ if (originalStamp.nonNull()) {
+ n = piNode.getOriginalNode();
+ } else {
+ break;
+ }
+ }
+ return n;
+ }
+
+ /**
+ * 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 value The node whose original value should be determined.
+ * @return The original value (which might be the input value itself).
+ */
+ public static ValueNode originalValue(ValueNode value) {
+ ValueNode result = originalValueSimple(value);
+ assert result != null;
+ return result;
+ }
+
+ private static ValueNode originalValueSimple(ValueNode value) {
+ /* The very simple case: look through proxies. */
+ ValueNode cur = originalValueForProxy(value);
+
+ while (cur instanceof PhiNode) {
+ /*
+ * We found a phi function. Check if we can analyze it without allocating temporary data
+ * structures.
+ */
+ PhiNode phi = (PhiNode) cur;
+
+ ValueNode phiSingleValue = null;
+ int count = phi.valueCount();
+ for (int i = 0; i < count; ++i) {
+ ValueNode phiCurValue = originalValueForProxy(phi.valueAt(i));
+ if (phiCurValue == phi) {
+ /* Simple cycle, we can ignore the input value. */
+ } else if (phiSingleValue == null) {
+ /* The first input. */
+ phiSingleValue = phiCurValue;
+ } else if (phiSingleValue != phiCurValue) {
+ /* Another input that is different from the first input. */
+
+ if (phiSingleValue instanceof PhiNode || phiCurValue instanceof PhiNode) {
+ /*
+ * We have two different input values for the phi function, and at least one
+ * of the inputs is another phi function. We need to do a complicated
+ * exhaustive check.
+ */
+ return originalValueForComplicatedPhi(phi, new NodeBitMap(value.graph()));
+ } else {
+ /*
+ * We have two different input values for the phi function, but none of them
+ * is another phi function. This phi function cannot be reduce any further,
+ * so the phi function is the original value.
+ */
+ return phi;
+ }
+ }
+ }
+
+ /*
+ * Successfully reduced the phi function to a single input value. The single input value
+ * can itself be a phi function again, so we might take another loop iteration.
+ */
+ assert phiSingleValue != null;
+ cur = phiSingleValue;
+ }
+
+ /* We reached a "normal" node, which is the original value. */
+ assert !(cur instanceof LimitedValueProxy) && !(cur instanceof PhiNode);
+ return cur;
+ }
+
+ private static ValueNode originalValueForProxy(ValueNode value) {
+ ValueNode cur = value;
+ while (cur instanceof LimitedValueProxy) {
+ cur = ((LimitedValueProxy) cur).getOriginalNode();
+ }
+ return cur;
+ }
+
+ /**
+ * Handling for complicated nestings of phi functions. We need to reduce phi functions
+ * recursively, and need a temporary map of visited nodes to avoid endless recursion of cycles.
+ */
+ private static ValueNode originalValueForComplicatedPhi(PhiNode phi, NodeBitMap visited) {
+ if (visited.isMarked(phi)) {
+ /*
+ * Found a phi function that was already seen. Either a cycle, or just a second phi
+ * input to a path we have already processed.
+ */
+ return null;
+ }
+ visited.mark(phi);
+
+ ValueNode phiSingleValue = null;
+ int count = phi.valueCount();
+ for (int i = 0; i < count; ++i) {
+ ValueNode phiCurValue = originalValueForProxy(phi.valueAt(i));
+ if (phiCurValue instanceof PhiNode) {
+ /* Recursively process a phi function input. */
+ phiCurValue = originalValueForComplicatedPhi((PhiNode) phiCurValue, visited);
+ }
+
+ if (phiCurValue == null) {
+ /* Cycle to a phi function that was already seen. We can ignore this input. */
+ } else if (phiSingleValue == null) {
+ /* The first input. */
+ phiSingleValue = phiCurValue;
+ } else if (phiCurValue != phiSingleValue) {
+ /*
+ * Another input that is different from the first input. Since we already
+ * recursively looked through other phi functions, we now know that this phi
+ * function cannot be reduce any further, so the phi function is the original value.
+ */
+ return phi;
+ }
+ }
+ return phiSingleValue;
+ }
+
+ public static boolean tryKillUnused(Node node) {
+ if (node.isAlive() && isFloatingNode(node) && node.hasNoUsages() && !(node instanceof GuardNode)) {
+ killWithUnusedFloatingInputs(node);
+ return true;
+ }
+ return false;
+ }
+
+ /**
+ * 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 OptionValues options;
+ private final LoweringProvider loweringProvider;
+
+ DefaultSimplifierTool(MetaAccessProvider metaAccess, ConstantReflectionProvider constantReflection, ConstantFieldProvider constantFieldProvider, boolean canonicalizeReads,
+ Assumptions assumptions, OptionValues options, LoweringProvider loweringProvider) {
+ this.metaAccess = metaAccess;
+ this.constantReflection = constantReflection;
+ this.constantFieldProvider = constantFieldProvider;
+ this.canonicalizeReads = canonicalizeReads;
+ this.assumptions = assumptions;
+ this.options = options;
+ 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);
+ }
+
+ @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 OptionValues getOptions() {
+ return options;
+ }
+
+ @Override
+ public Integer smallestCompareWidth() {
+ if (loweringProvider != null) {
+ return loweringProvider.smallestCompareWidth();
+ } else {
+ return null;
+ }
+ }
+ }
+
+ public static SimplifierTool getDefaultSimplifier(MetaAccessProvider metaAccess, ConstantReflectionProvider constantReflection, ConstantFieldProvider constantFieldProvider,
+ boolean canonicalizeReads, Assumptions assumptions, OptionValues options) {
+ return getDefaultSimplifier(metaAccess, constantReflection, constantFieldProvider, canonicalizeReads, assumptions, options, null);
+ }
+
+ public static SimplifierTool getDefaultSimplifier(MetaAccessProvider metaAccess, ConstantReflectionProvider constantReflection, ConstantFieldProvider constantFieldProvider,
+ boolean canonicalizeReads, Assumptions assumptions, OptionValues options, LoweringProvider loweringProvider) {
+ return new DefaultSimplifierTool(metaAccess, constantReflection, constantFieldProvider, canonicalizeReads, assumptions, options, 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;
+ }
+
+ /**
+ * Virtualize an array copy.
+ *
+ * @param tool the virtualization tool
+ * @param source the source array
+ * @param sourceLength the length of the source array
+ * @param newLength the length of the new array
+ * @param from the start index in the source array
+ * @param newComponentType the component type of the new array
+ * @param elementKind the kind of the new array elements
+ * @param graph the node graph
+ * @param virtualArrayProvider a functional provider that returns a new virtual array given the
+ * component type and length
+ */
+ public static void virtualizeArrayCopy(VirtualizerTool tool, ValueNode source, ValueNode sourceLength, ValueNode newLength, ValueNode from, ResolvedJavaType newComponentType, JavaKind elementKind,
+ StructuredGraph graph, BiFunction<ResolvedJavaType, Integer, VirtualArrayNode> virtualArrayProvider) {
+
+ ValueNode sourceAlias = tool.getAlias(source);
+ ValueNode replacedSourceLength = tool.getAlias(sourceLength);
+ ValueNode replacedNewLength = tool.getAlias(newLength);
+ ValueNode replacedFrom = tool.getAlias(from);
+ if (!replacedNewLength.isConstant() || !replacedFrom.isConstant() || !replacedSourceLength.isConstant()) {
+ return;
+ }
+
+ assert newComponentType != null : "An array copy can be virtualized only if the real type of the resulting array is known statically.";
+
+ int fromInt = replacedFrom.asJavaConstant().asInt();
+ int newLengthInt = replacedNewLength.asJavaConstant().asInt();
+ int sourceLengthInt = replacedSourceLength.asJavaConstant().asInt();
+ if (sourceAlias instanceof VirtualObjectNode) {
+ VirtualObjectNode sourceVirtual = (VirtualObjectNode) sourceAlias;
+ assert sourceLengthInt == sourceVirtual.entryCount();
+ }
+
+ if (fromInt < 0 || newLengthInt < 0 || fromInt > sourceLengthInt) {
+ /* Illegal values for either from index, the new length or the source length. */
+ return;
+ }
+
+ if (newLengthInt >= tool.getMaximumEntryCount()) {
+ /* The new array size is higher than maximum allowed size of virtualized objects. */
+ return;
+ }
+
+ ValueNode[] newEntryState = new ValueNode[newLengthInt];
+ int readLength = Math.min(newLengthInt, sourceLengthInt - fromInt);
+
+ if (sourceAlias instanceof VirtualObjectNode) {
+ /* The source array is virtualized, just copy over the values. */
+ VirtualObjectNode sourceVirtual = (VirtualObjectNode) sourceAlias;
+ for (int i = 0; i < readLength; i++) {
+ newEntryState[i] = tool.getEntry(sourceVirtual, fromInt + i);
+ }
+ } else {
+ /* The source array is not virtualized, emit index loads. */
+ for (int i = 0; i < readLength; i++) {
+ LoadIndexedNode load = new LoadIndexedNode(null, sourceAlias, ConstantNode.forInt(i + fromInt, graph), elementKind);
+ tool.addNode(load);
+ newEntryState[i] = load;
+ }
+ }
+ if (readLength < newLengthInt) {
+ /* Pad the copy with the default value of its elment kind. */
+ ValueNode defaultValue = ConstantNode.defaultForKind(elementKind, graph);
+ for (int i = readLength; i < newLengthInt; i++) {
+ newEntryState[i] = defaultValue;
+ }
+ }
+ /* Perform the replacement. */
+ VirtualArrayNode newVirtualArray = virtualArrayProvider.apply(newComponentType, newLengthInt);
+ tool.createVirtualObject(newVirtualArray, newEntryState, Collections.<MonitorIdNode> emptyList(), false);
+ tool.replaceWithVirtual(newVirtualArray);
+ }
+}