hotspot/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.phases/src/org/graalvm/compiler/phases/util/GraphOrder.java
changeset 43972 1ade39b8381b
child 46344 694c102fd8ed
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.phases/src/org/graalvm/compiler/phases/util/GraphOrder.java	Thu Feb 16 15:46:09 2017 -0800
@@ -0,0 +1,296 @@
+/*
+ * Copyright (c) 2011, 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 org.graalvm.compiler.phases.util;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+
+import org.graalvm.compiler.core.common.cfg.Loop;
+import org.graalvm.compiler.debug.Debug;
+import org.graalvm.compiler.debug.GraalError;
+import org.graalvm.compiler.graph.GraalGraphError;
+import org.graalvm.compiler.graph.Node;
+import org.graalvm.compiler.graph.NodeBitMap;
+import org.graalvm.compiler.nodes.AbstractEndNode;
+import org.graalvm.compiler.nodes.AbstractMergeNode;
+import org.graalvm.compiler.nodes.ConstantNode;
+import org.graalvm.compiler.nodes.EndNode;
+import org.graalvm.compiler.nodes.FixedNode;
+import org.graalvm.compiler.nodes.FrameState;
+import org.graalvm.compiler.nodes.FullInfopointNode;
+import org.graalvm.compiler.nodes.LoopBeginNode;
+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.StructuredGraph.GuardsStage;
+import org.graalvm.compiler.nodes.StructuredGraph.ScheduleResult;
+import org.graalvm.compiler.nodes.ValueNode;
+import org.graalvm.compiler.nodes.VirtualState;
+import org.graalvm.compiler.nodes.VirtualState.NodeClosure;
+import org.graalvm.compiler.nodes.cfg.Block;
+import org.graalvm.compiler.nodes.virtual.VirtualObjectNode;
+import org.graalvm.compiler.phases.graph.ReentrantBlockIterator;
+import org.graalvm.compiler.phases.graph.ReentrantBlockIterator.BlockIteratorClosure;
+import org.graalvm.compiler.phases.graph.StatelessPostOrderNodeIterator;
+import org.graalvm.compiler.phases.schedule.SchedulePhase;
+import org.graalvm.compiler.phases.schedule.SchedulePhase.SchedulingStrategy;
+
+public final class GraphOrder {
+
+    private GraphOrder() {
+    }
+
+    /**
+     * Quick (and imprecise) assertion that there are no (invalid) cycles in the given graph. First,
+     * an ordered list of all nodes in the graph (a total ordering) is created. A second run over
+     * this list checks whether inputs are scheduled before their usages.
+     *
+     * @param graph the graph to be checked.
+     * @throws AssertionError if a cycle was detected.
+     */
+    public static boolean assertNonCyclicGraph(StructuredGraph graph) {
+        List<Node> order = createOrder(graph);
+        NodeBitMap visited = graph.createNodeBitMap();
+        visited.clearAll();
+        for (Node node : order) {
+            if (node instanceof PhiNode && ((PhiNode) node).merge() instanceof LoopBeginNode) {
+                assert visited.isMarked(((PhiNode) node).valueAt(0));
+                // nothing to do
+            } else {
+                for (Node input : node.inputs()) {
+                    if (!visited.isMarked(input)) {
+                        if (input instanceof FrameState) {
+                            // nothing to do - frame states are known, allowed cycles
+                        } else {
+                            assert false : "unexpected cycle detected at input " + node + " -> " + input;
+                        }
+                    }
+                }
+            }
+            visited.mark(node);
+        }
+        return true;
+    }
+
+    private static List<Node> createOrder(StructuredGraph graph) {
+        final ArrayList<Node> nodes = new ArrayList<>();
+        final NodeBitMap visited = graph.createNodeBitMap();
+
+        new StatelessPostOrderNodeIterator(graph.start()) {
+            @Override
+            protected void node(FixedNode node) {
+                visitForward(nodes, visited, node, false);
+            }
+        }.apply();
+        return nodes;
+    }
+
+    private static void visitForward(ArrayList<Node> nodes, NodeBitMap visited, Node node, boolean floatingOnly) {
+        try {
+            assert node == null || node.isAlive() : node + " not alive";
+            if (node != null && !visited.isMarked(node)) {
+                if (floatingOnly && node instanceof FixedNode) {
+                    throw new GraalError("unexpected reference to fixed node: %s (this indicates an unexpected cycle)", node);
+                }
+                visited.mark(node);
+                FrameState stateAfter = null;
+                if (node instanceof StateSplit) {
+                    stateAfter = ((StateSplit) node).stateAfter();
+                }
+                for (Node input : node.inputs()) {
+                    if (input != stateAfter) {
+                        visitForward(nodes, visited, input, true);
+                    }
+                }
+                if (node instanceof EndNode) {
+                    EndNode end = (EndNode) node;
+                    for (PhiNode phi : end.merge().phis()) {
+                        visitForward(nodes, visited, phi.valueAt(end), true);
+                    }
+                }
+                nodes.add(node);
+                if (node instanceof AbstractMergeNode) {
+                    for (PhiNode phi : ((AbstractMergeNode) node).phis()) {
+                        visited.mark(phi);
+                        nodes.add(phi);
+                    }
+                }
+                if (stateAfter != null) {
+                    visitForward(nodes, visited, stateAfter, true);
+                }
+            }
+        } catch (GraalError e) {
+            throw GraalGraphError.transformAndAddContext(e, node);
+        }
+    }
+
+    /**
+     * This method schedules the graph and makes sure that, for every node, all inputs are available
+     * at the position where it is scheduled. This is a very expensive assertion.
+     */
+    public static boolean assertSchedulableGraph(final StructuredGraph graph) {
+        assert graph.getGuardsStage() != GuardsStage.AFTER_FSA : "Cannot use the BlockIteratorClosure after FrameState Assignment, HIR Loop Data Structures are no longer valid.";
+        try {
+            final SchedulePhase schedulePhase = new SchedulePhase(SchedulingStrategy.LATEST_OUT_OF_LOOPS);
+            final Map<LoopBeginNode, NodeBitMap> loopEntryStates = Node.newIdentityMap();
+            schedulePhase.apply(graph, false);
+            final ScheduleResult schedule = graph.getLastSchedule();
+
+            BlockIteratorClosure<NodeBitMap> closure = new BlockIteratorClosure<NodeBitMap>() {
+
+                @Override
+                protected List<NodeBitMap> processLoop(Loop<Block> loop, NodeBitMap initialState) {
+                    return ReentrantBlockIterator.processLoop(this, loop, initialState).exitStates;
+                }
+
+                @Override
+                protected NodeBitMap processBlock(final Block block, final NodeBitMap currentState) {
+                    final List<Node> list = graph.getLastSchedule().getBlockToNodesMap().get(block);
+
+                    /*
+                     * A stateAfter is not valid directly after its associated state split, but
+                     * right before the next fixed node. Therefore a pending stateAfter is kept that
+                     * will be checked at the correct position.
+                     */
+                    FrameState pendingStateAfter = null;
+                    for (final Node node : list) {
+                        if (node instanceof ValueNode) {
+                            FrameState stateAfter = node instanceof StateSplit ? ((StateSplit) node).stateAfter() : null;
+                            if (node instanceof FullInfopointNode) {
+                                stateAfter = ((FullInfopointNode) node).getState();
+                            }
+
+                            if (pendingStateAfter != null && node instanceof FixedNode) {
+                                pendingStateAfter.applyToNonVirtual(new NodeClosure<Node>() {
+                                    @Override
+                                    public void apply(Node usage, Node nonVirtualNode) {
+                                        assert currentState.isMarked(nonVirtualNode) || nonVirtualNode instanceof VirtualObjectNode || nonVirtualNode instanceof ConstantNode : nonVirtualNode +
+                                                        " not available at virtualstate " + usage + " before " + node + " in block " + block + " \n" + list;
+                                    }
+                                });
+                                pendingStateAfter = null;
+                            }
+
+                            if (node instanceof AbstractMergeNode) {
+                                // phis aren't scheduled, so they need to be added explicitly
+                                currentState.markAll(((AbstractMergeNode) node).phis());
+                                if (node instanceof LoopBeginNode) {
+                                    // remember the state at the loop entry, it's restored at exits
+                                    loopEntryStates.put((LoopBeginNode) node, currentState.copy());
+                                }
+                            } else if (node instanceof ProxyNode) {
+                                assert false : "proxy nodes should not be in the schedule";
+                            } else if (node instanceof LoopExitNode) {
+                                if (graph.hasValueProxies()) {
+                                    for (ProxyNode proxy : ((LoopExitNode) node).proxies()) {
+                                        for (Node input : proxy.inputs()) {
+                                            if (input != proxy.proxyPoint()) {
+                                                assert currentState.isMarked(input) : input + " not available at " + proxy + " in block " + block + "\n" + list;
+                                            }
+                                        }
+                                    }
+
+                                    // loop contents are only accessible via proxies at the exit
+                                    currentState.clearAll();
+                                    currentState.markAll(loopEntryStates.get(((LoopExitNode) node).loopBegin()));
+                                }
+                                // Loop proxies aren't scheduled, so they need to be added
+                                // explicitly
+                                currentState.markAll(((LoopExitNode) node).proxies());
+                            } else {
+                                for (Node input : node.inputs()) {
+                                    if (input != stateAfter) {
+                                        if (input instanceof FrameState) {
+                                            ((FrameState) input).applyToNonVirtual(new VirtualState.NodeClosure<Node>() {
+                                                @Override
+                                                public void apply(Node usage, Node nonVirtual) {
+                                                    assert currentState.isMarked(nonVirtual) : nonVirtual + " not available at " + node + " in block " + block + "\n" + list;
+                                                }
+                                            });
+                                        } else {
+                                            assert currentState.isMarked(input) || input instanceof VirtualObjectNode || input instanceof ConstantNode : input + " not available at " + node +
+                                                            " in block " + block + "\n" + list;
+                                        }
+                                    }
+                                }
+                            }
+                            if (node instanceof AbstractEndNode) {
+                                AbstractMergeNode merge = ((AbstractEndNode) node).merge();
+                                for (PhiNode phi : merge.phis()) {
+                                    ValueNode phiValue = phi.valueAt((AbstractEndNode) node);
+                                    assert phiValue == null || currentState.isMarked(phiValue) || phiValue instanceof ConstantNode : phiValue + " not available at phi " + phi + " / end " + node +
+                                                    " in block " + block;
+                                }
+                            }
+                            if (stateAfter != null) {
+                                assert pendingStateAfter == null;
+                                pendingStateAfter = stateAfter;
+                            }
+                            currentState.mark(node);
+                        }
+                    }
+                    if (pendingStateAfter != null) {
+                        pendingStateAfter.applyToNonVirtual(new NodeClosure<Node>() {
+                            @Override
+                            public void apply(Node usage, Node nonVirtualNode) {
+                                assert currentState.isMarked(nonVirtualNode) || nonVirtualNode instanceof VirtualObjectNode || nonVirtualNode instanceof ConstantNode : nonVirtualNode +
+                                                " not available at virtualstate " + usage + " at end of block " + block + " \n" + list;
+                            }
+                        });
+                    }
+                    return currentState;
+                }
+
+                @Override
+                protected NodeBitMap merge(Block merge, List<NodeBitMap> states) {
+                    NodeBitMap result = states.get(0);
+                    for (int i = 1; i < states.size(); i++) {
+                        result.intersect(states.get(i));
+                    }
+                    return result;
+                }
+
+                @Override
+                protected NodeBitMap getInitialState() {
+                    NodeBitMap ret = graph.createNodeBitMap();
+                    ret.markAll(graph.getNodes().filter(ConstantNode.class));
+                    return ret;
+                }
+
+                @Override
+                protected NodeBitMap cloneState(NodeBitMap oldState) {
+                    return oldState.copy();
+                }
+            };
+
+            ReentrantBlockIterator.apply(closure, schedule.getCFG().getStartBlock());
+
+        } catch (Throwable t) {
+            Debug.handle(t);
+        }
+        return true;
+    }
+}