--- /dev/null 2017-01-22 10:16:57.869617664 -0800 +++ new/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.virtual/src/org/graalvm/compiler/virtual/phases/ea/EffectsClosure.java 2017-02-15 17:09:36.237407770 -0800 @@ -0,0 +1,506 @@ +/* + * 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.virtual.phases.ea; + +import java.util.ArrayList; +import java.util.HashSet; +import java.util.List; +import java.util.Map; +import java.util.Set; + +import org.graalvm.compiler.core.common.CollectionsFactory; +import org.graalvm.compiler.core.common.LocationIdentity; +import org.graalvm.compiler.core.common.cfg.BlockMap; +import org.graalvm.compiler.core.common.cfg.Loop; +import org.graalvm.compiler.core.common.type.Stamp; +import org.graalvm.compiler.debug.Debug; +import org.graalvm.compiler.debug.GraalError; +import org.graalvm.compiler.debug.Indent; +import org.graalvm.compiler.graph.Node; +import org.graalvm.compiler.graph.NodeBitMap; +import org.graalvm.compiler.graph.NodeMap; +import org.graalvm.compiler.graph.iterators.NodeIterable; +import org.graalvm.compiler.nodes.AbstractMergeNode; +import org.graalvm.compiler.nodes.FixedWithNextNode; +import org.graalvm.compiler.nodes.IfNode; +import org.graalvm.compiler.nodes.LogicConstantNode; +import org.graalvm.compiler.nodes.LogicNode; +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.StructuredGraph; +import org.graalvm.compiler.nodes.StructuredGraph.ScheduleResult; +import org.graalvm.compiler.nodes.ValueNode; +import org.graalvm.compiler.nodes.ValuePhiNode; +import org.graalvm.compiler.nodes.cfg.Block; +import org.graalvm.compiler.nodes.cfg.ControlFlowGraph; +import org.graalvm.compiler.nodes.extended.BoxNode; +import org.graalvm.compiler.nodes.util.GraphUtil; +import org.graalvm.compiler.nodes.virtual.AllocatedObjectNode; +import org.graalvm.compiler.nodes.virtual.CommitAllocationNode; +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.ReentrantBlockIterator.LoopInfo; + +public abstract class EffectsClosure> extends EffectsPhase.Closure { + + protected final ControlFlowGraph cfg; + protected final ScheduleResult schedule; + + protected final NodeMap aliases; + protected final BlockMap blockEffects; + private final Map, GraphEffectList> loopMergeEffects = CollectionsFactory.newIdentityMap(); + // Intended to be used by read-eliminating phases based on the effects phase. + protected final Map, LoopKillCache> loopLocationKillCache = CollectionsFactory.newIdentityMap(); + private final Map loopEntryStates = Node.newIdentityMap(); + private final NodeBitMap hasScalarReplacedInputs; + + protected boolean changed; + + public EffectsClosure(ScheduleResult schedule, ControlFlowGraph cfg) { + this.schedule = schedule; + this.cfg = cfg; + this.aliases = cfg.graph.createNodeMap(); + this.hasScalarReplacedInputs = cfg.graph.createNodeBitMap(); + this.blockEffects = new BlockMap<>(cfg); + for (Block block : cfg.getBlocks()) { + blockEffects.put(block, new GraphEffectList()); + } + } + + @Override + public boolean hasChanged() { + return changed; + } + + @Override + public void applyEffects() { + final StructuredGraph graph = cfg.graph; + final ArrayList obsoleteNodes = new ArrayList<>(0); + final ArrayList effectList = new ArrayList<>(); + BlockIteratorClosure closure = new BlockIteratorClosure() { + + @Override + protected Void getInitialState() { + return null; + } + + private void apply(GraphEffectList effects) { + if (effects != null && !effects.isEmpty()) { + effectList.add(effects); + } + } + + @Override + protected Void processBlock(Block block, Void currentState) { + apply(blockEffects.get(block)); + return currentState; + } + + @Override + protected Void merge(Block merge, List states) { + return null; + } + + @Override + protected Void cloneState(Void oldState) { + return oldState; + } + + @Override + protected List processLoop(Loop loop, Void initialState) { + LoopInfo info = ReentrantBlockIterator.processLoop(this, loop, initialState); + apply(loopMergeEffects.get(loop)); + return info.exitStates; + } + }; + ReentrantBlockIterator.apply(closure, cfg.getStartBlock()); + for (GraphEffectList effects : effectList) { + Debug.log(" ==== effects"); + effects.apply(graph, obsoleteNodes, false); + } + for (GraphEffectList effects : effectList) { + Debug.log(" ==== cfg kill effects"); + effects.apply(graph, obsoleteNodes, true); + } + Debug.dump(Debug.VERBOSE_LOG_LEVEL, graph, "After applying effects"); + assert VirtualUtil.assertNonReachable(graph, obsoleteNodes); + for (Node node : obsoleteNodes) { + if (node.isAlive()) { + node.replaceAtUsages(null); + GraphUtil.killWithUnusedFloatingInputs(node); + } + } + } + + @Override + protected BlockT processBlock(Block block, BlockT state) { + if (!state.isDead()) { + GraphEffectList effects = blockEffects.get(block); + + if (block.getBeginNode().predecessor() instanceof IfNode) { + IfNode ifNode = (IfNode) block.getBeginNode().predecessor(); + LogicNode condition = ifNode.condition(); + Node alias = getScalarAlias(condition); + if (alias instanceof LogicConstantNode) { + LogicConstantNode constant = (LogicConstantNode) alias; + boolean deadBranch = constant.getValue() != (block.getBeginNode() == ifNode.trueSuccessor()); + + if (deadBranch) { + state.markAsDead(); + effects.killIfBranch(ifNode, constant.getValue()); + return state; + } + } + } + + VirtualUtil.trace("\nBlock: %s, preds: %s, succ: %s (", block, block.getPredecessors(), block.getSuccessors()); + + FixedWithNextNode lastFixedNode = block.getBeginNode().predecessor() instanceof FixedWithNextNode ? (FixedWithNextNode) block.getBeginNode().predecessor() : null; + Iterable nodes = schedule != null ? schedule.getBlockToNodesMap().get(block) : block.getNodes(); + for (Node node : nodes) { + aliases.set(node, null); + if (node instanceof LoopExitNode) { + LoopExitNode loopExit = (LoopExitNode) node; + for (ProxyNode proxy : loopExit.proxies()) { + aliases.set(proxy, null); + changed |= processNode(proxy, state, effects, lastFixedNode) && isSignificantNode(node); + } + processLoopExit(loopExit, loopEntryStates.get(loopExit.loopBegin()), state, blockEffects.get(block)); + } + changed |= processNode(node, state, effects, lastFixedNode) && isSignificantNode(node); + if (node instanceof FixedWithNextNode) { + lastFixedNode = (FixedWithNextNode) node; + } + if (state.isDead()) { + break; + } + } + VirtualUtil.trace(")\n end state: %s\n", state); + } + return state; + } + + private static boolean isSignificantNode(Node node) { + return !(node instanceof CommitAllocationNode || node instanceof AllocatedObjectNode || node instanceof BoxNode); + } + + /** + * Collects the effects of virtualizing the given node. + * + * @return {@code true} if the effects include removing the node, {@code false} otherwise. + */ + protected abstract boolean processNode(Node node, BlockT state, GraphEffectList effects, FixedWithNextNode lastFixedNode); + + @Override + protected BlockT merge(Block merge, List states) { + assert blockEffects.get(merge).isEmpty(); + MergeProcessor processor = createMergeProcessor(merge); + doMergeWithoutDead(processor, states); + processor.commitEnds(states); + blockEffects.get(merge).addAll(processor.mergeEffects); + blockEffects.get(merge).addAll(processor.afterMergeEffects); + return processor.newState; + } + + @Override + @SuppressWarnings("try") + protected final List processLoop(Loop loop, BlockT initialState) { + if (initialState.isDead()) { + ArrayList states = new ArrayList<>(); + for (int i = 0; i < loop.getExits().size(); i++) { + states.add(initialState); + } + return states; + } + /* + * Special case nested loops: To avoid an exponential runtime for nested loops we try to + * only process them as little times as possible. + * + * In the first iteration of an outer most loop we go into the inner most loop(s). We run + * the first iteration of the inner most loop and then, if necessary, a second iteration. + * + * We return from the recursion and finish the first iteration of the outermost loop. If we + * have to do a second iteration in the outer most loop we go again into the inner most + * loop(s) but this time we already know all states that are killed by the loop so inside + * the loop we will only have those changes that propagate from the first iteration of the + * outer most loop into the current loop. We strip the initial loop state for the inner most + * loops and do the first iteration with the (possible) changes from outer loops. If there + * are no changes we only have to do 1 iteration and are done. + * + */ + BlockT initialStateRemovedKilledLocations = stripKilledLoopLocations(loop, cloneState(initialState)); + BlockT loopEntryState = initialStateRemovedKilledLocations; + BlockT lastMergedState = cloneState(initialStateRemovedKilledLocations); + processInitialLoopState(loop, lastMergedState); + MergeProcessor mergeProcessor = createMergeProcessor(loop.getHeader()); + for (int iteration = 0; iteration < 10; iteration++) { + try (Indent i = Debug.logAndIndent("================== Process Loop Effects Closure: block:%s begin node:%s", loop.getHeader(), loop.getHeader().getBeginNode())) { + LoopInfo info = ReentrantBlockIterator.processLoop(this, loop, cloneState(lastMergedState)); + + List states = new ArrayList<>(); + states.add(initialStateRemovedKilledLocations); + states.addAll(info.endStates); + doMergeWithoutDead(mergeProcessor, states); + + Debug.log("MergeProcessor New State: %s", mergeProcessor.newState); + Debug.log("===== vs."); + Debug.log("Last Merged State: %s", lastMergedState); + + if (mergeProcessor.newState.equivalentTo(lastMergedState)) { + mergeProcessor.commitEnds(states); + + blockEffects.get(loop.getHeader()).insertAll(mergeProcessor.mergeEffects, 0); + loopMergeEffects.put(loop, mergeProcessor.afterMergeEffects); + + assert info.exitStates.size() == loop.getExits().size(); + loopEntryStates.put((LoopBeginNode) loop.getHeader().getBeginNode(), loopEntryState); + assert assertExitStatesNonEmpty(loop, info); + + processKilledLoopLocations(loop, initialStateRemovedKilledLocations, mergeProcessor.newState); + return info.exitStates; + } else { + lastMergedState = mergeProcessor.newState; + for (Block block : loop.getBlocks()) { + blockEffects.get(block).clear(); + } + } + } + } + throw new GraalError("too many iterations at %s", loop); + } + + @SuppressWarnings("unused") + protected BlockT stripKilledLoopLocations(Loop loop, BlockT initialState) { + return initialState; + } + + @SuppressWarnings("unused") + protected void processKilledLoopLocations(Loop loop, BlockT initialState, BlockT mergedStates) { + // nothing to do + } + + @SuppressWarnings("unused") + protected void processInitialLoopState(Loop loop, BlockT initialState) { + // nothing to do + } + + private void doMergeWithoutDead(MergeProcessor mergeProcessor, List states) { + int alive = 0; + for (BlockT state : states) { + if (!state.isDead()) { + alive++; + } + } + if (alive == 0) { + mergeProcessor.setNewState(states.get(0)); + } else if (alive == states.size()) { + int[] stateIndexes = new int[states.size()]; + for (int i = 0; i < stateIndexes.length; i++) { + stateIndexes[i] = i; + } + mergeProcessor.setStateIndexes(stateIndexes); + mergeProcessor.merge(states); + } else { + ArrayList aliveStates = new ArrayList<>(alive); + int[] stateIndexes = new int[alive]; + for (int i = 0; i < states.size(); i++) { + if (!states.get(i).isDead()) { + stateIndexes[aliveStates.size()] = i; + aliveStates.add(states.get(i)); + } + } + mergeProcessor.setStateIndexes(stateIndexes); + mergeProcessor.merge(aliveStates); + } + } + + private boolean assertExitStatesNonEmpty(Loop loop, LoopInfo info) { + for (int i = 0; i < loop.getExits().size(); i++) { + assert info.exitStates.get(i) != null : "no loop exit state at " + loop.getExits().get(i) + " / " + loop.getHeader(); + } + return true; + } + + protected abstract void processLoopExit(LoopExitNode exitNode, BlockT initialState, BlockT exitState, GraphEffectList effects); + + protected abstract MergeProcessor createMergeProcessor(Block merge); + + protected class MergeProcessor { + + private final Block mergeBlock; + private final AbstractMergeNode merge; + + protected final GraphEffectList mergeEffects; + protected final GraphEffectList afterMergeEffects; + + private int[] stateIndexes; + protected BlockT newState; + + public MergeProcessor(Block mergeBlock) { + this.mergeBlock = mergeBlock; + this.merge = (AbstractMergeNode) mergeBlock.getBeginNode(); + this.mergeEffects = new GraphEffectList(); + this.afterMergeEffects = new GraphEffectList(); + } + + /** + * @param states the states that should be merged. + */ + protected void merge(List states) { + setNewState(getInitialState()); + } + + private void setNewState(BlockT state) { + newState = state; + mergeEffects.clear(); + afterMergeEffects.clear(); + } + + private void setStateIndexes(int[] stateIndexes) { + this.stateIndexes = stateIndexes; + } + + @SuppressWarnings("unused") + protected void commitEnds(List states) { + } + + protected final Block getPredecessor(int index) { + return mergeBlock.getPredecessors()[stateIndexes[index]]; + } + + protected final NodeIterable getPhis() { + return merge.phis(); + } + + protected final ValueNode getPhiValueAt(PhiNode phi, int index) { + return phi.valueAt(stateIndexes[index]); + } + + protected final ValuePhiNode createValuePhi(Stamp stamp) { + return new ValuePhiNode(stamp, merge, new ValueNode[mergeBlock.getPredecessorCount()]); + } + + protected final void setPhiInput(PhiNode phi, int index, ValueNode value) { + afterMergeEffects.initializePhiInput(phi, stateIndexes[index], value); + } + + protected final int getStateIndex(int i) { + return stateIndexes[i]; + } + + protected final StructuredGraph graph() { + return merge.graph(); + } + + @Override + public String toString() { + return "MergeProcessor@" + merge; + } + } + + public void addScalarAlias(ValueNode node, ValueNode alias) { + assert !(alias instanceof VirtualObjectNode); + aliases.set(node, alias); + for (Node usage : node.usages()) { + if (!hasScalarReplacedInputs.isNew(usage)) { + hasScalarReplacedInputs.mark(usage); + } + } + } + + protected final boolean hasScalarReplacedInputs(Node node) { + return hasScalarReplacedInputs.isMarked(node); + } + + public ValueNode getScalarAlias(ValueNode node) { + assert !(node instanceof VirtualObjectNode); + if (node == null || !node.isAlive() || aliases.isNew(node)) { + return node; + } + ValueNode result = aliases.get(node); + return (result == null || result instanceof VirtualObjectNode) ? node : result; + } + + protected static class LoopKillCache { + private int visits; + private LocationIdentity firstLocation; + private Set killedLocations; + private boolean killsAll; + + protected LoopKillCache(int visits) { + this.visits = visits; + } + + protected void visited() { + visits++; + } + + protected int visits() { + return visits; + } + + protected void setKillsAll() { + killsAll = true; + firstLocation = null; + killedLocations = null; + } + + protected boolean containsLocation(LocationIdentity locationIdentity) { + if (killsAll) { + return true; + } + if (firstLocation == null) { + return false; + } + if (!firstLocation.equals(locationIdentity)) { + return killedLocations != null ? killedLocations.contains(locationIdentity) : false; + } + return true; + } + + protected void rememberLoopKilledLocation(LocationIdentity locationIdentity) { + if (killsAll) { + return; + } + if (firstLocation == null || firstLocation.equals(locationIdentity)) { + firstLocation = locationIdentity; + } else { + if (killedLocations == null) { + killedLocations = new HashSet<>(); + } + killedLocations.add(locationIdentity); + } + } + + protected boolean loopKillsLocations() { + if (killsAll) { + return true; + } + return firstLocation != null; + } + } + +}