| /* |
| * Copyright (c) 2011, 2016, 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.common; |
| |
| import static org.graalvm.compiler.core.common.GraalOptions.OptEliminateGuards; |
| import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_IGNORED; |
| import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_IGNORED; |
| import static org.graalvm.compiler.phases.common.LoweringPhase.ProcessBlockState.ST_ENTER; |
| import static org.graalvm.compiler.phases.common.LoweringPhase.ProcessBlockState.ST_ENTER_ALWAYS_REACHED; |
| import static org.graalvm.compiler.phases.common.LoweringPhase.ProcessBlockState.ST_LEAVE; |
| import static org.graalvm.compiler.phases.common.LoweringPhase.ProcessBlockState.ST_PROCESS; |
| import static org.graalvm.compiler.phases.common.LoweringPhase.ProcessBlockState.ST_PROCESS_ALWAYS_REACHED; |
| |
| import java.util.ArrayList; |
| import java.util.Collection; |
| import java.util.Iterator; |
| import java.util.List; |
| |
| import org.graalvm.compiler.core.common.spi.ConstantFieldProvider; |
| import org.graalvm.compiler.core.common.type.StampFactory; |
| import org.graalvm.compiler.debug.DebugCloseable; |
| import org.graalvm.compiler.debug.GraalError; |
| import org.graalvm.compiler.graph.Graph.Mark; |
| import org.graalvm.compiler.graph.Node; |
| import org.graalvm.compiler.graph.NodeBitMap; |
| import org.graalvm.compiler.graph.NodeClass; |
| import org.graalvm.compiler.graph.iterators.NodeIterable; |
| import org.graalvm.compiler.nodeinfo.InputType; |
| import org.graalvm.compiler.nodeinfo.NodeInfo; |
| import org.graalvm.compiler.nodes.AbstractBeginNode; |
| import org.graalvm.compiler.nodes.BeginNode; |
| import org.graalvm.compiler.nodes.FixedGuardNode; |
| import org.graalvm.compiler.nodes.FixedNode; |
| import org.graalvm.compiler.nodes.FixedWithNextNode; |
| import org.graalvm.compiler.nodes.GuardNode; |
| import org.graalvm.compiler.nodes.LogicNode; |
| import org.graalvm.compiler.nodes.StructuredGraph; |
| import org.graalvm.compiler.nodes.StructuredGraph.ScheduleResult; |
| import org.graalvm.compiler.nodes.ValueNode; |
| import org.graalvm.compiler.nodes.calc.FloatingNode; |
| import org.graalvm.compiler.nodes.cfg.Block; |
| import org.graalvm.compiler.nodes.extended.AnchoringNode; |
| import org.graalvm.compiler.nodes.extended.GuardedNode; |
| import org.graalvm.compiler.nodes.extended.GuardingNode; |
| import org.graalvm.compiler.nodes.spi.Lowerable; |
| import org.graalvm.compiler.nodes.spi.LoweringProvider; |
| import org.graalvm.compiler.nodes.spi.LoweringTool; |
| import org.graalvm.compiler.nodes.spi.NodeCostProvider; |
| import org.graalvm.compiler.nodes.spi.Replacements; |
| import org.graalvm.compiler.nodes.spi.StampProvider; |
| import org.graalvm.compiler.phases.BasePhase; |
| import org.graalvm.compiler.phases.Phase; |
| import org.graalvm.compiler.phases.schedule.SchedulePhase; |
| import org.graalvm.compiler.phases.tiers.PhaseContext; |
| |
| import jdk.vm.ci.meta.ConstantReflectionProvider; |
| import jdk.vm.ci.meta.DeoptimizationAction; |
| import jdk.vm.ci.meta.DeoptimizationReason; |
| import jdk.vm.ci.meta.JavaConstant; |
| import jdk.vm.ci.meta.MetaAccessProvider; |
| |
| /** |
| * Processes all {@link Lowerable} nodes to do their lowering. |
| */ |
| public class LoweringPhase extends BasePhase<PhaseContext> { |
| |
| @NodeInfo(cycles = CYCLES_IGNORED, size = SIZE_IGNORED) |
| static final class DummyGuardHandle extends ValueNode implements GuardedNode { |
| public static final NodeClass<DummyGuardHandle> TYPE = NodeClass.create(DummyGuardHandle.class); |
| @Input(InputType.Guard) GuardingNode guard; |
| |
| protected DummyGuardHandle(GuardingNode guard) { |
| super(TYPE, StampFactory.forVoid()); |
| this.guard = guard; |
| } |
| |
| @Override |
| public GuardingNode getGuard() { |
| return guard; |
| } |
| |
| @Override |
| public void setGuard(GuardingNode guard) { |
| updateUsagesInterface(this.guard, guard); |
| this.guard = guard; |
| } |
| |
| @Override |
| public ValueNode asNode() { |
| return this; |
| } |
| } |
| |
| @Override |
| public boolean checkContract() { |
| return false; |
| } |
| |
| final class LoweringToolImpl implements LoweringTool { |
| |
| private final PhaseContext context; |
| private final NodeBitMap activeGuards; |
| private AnchoringNode guardAnchor; |
| private FixedWithNextNode lastFixedNode; |
| |
| LoweringToolImpl(PhaseContext context, AnchoringNode guardAnchor, NodeBitMap activeGuards, FixedWithNextNode lastFixedNode) { |
| this.context = context; |
| this.guardAnchor = guardAnchor; |
| this.activeGuards = activeGuards; |
| this.lastFixedNode = lastFixedNode; |
| } |
| |
| @Override |
| public LoweringStage getLoweringStage() { |
| return loweringStage; |
| } |
| |
| @Override |
| public ConstantReflectionProvider getConstantReflection() { |
| return context.getConstantReflection(); |
| } |
| |
| @Override |
| public ConstantFieldProvider getConstantFieldProvider() { |
| return context.getConstantFieldProvider(); |
| } |
| |
| @Override |
| public MetaAccessProvider getMetaAccess() { |
| return context.getMetaAccess(); |
| } |
| |
| @Override |
| public LoweringProvider getLowerer() { |
| return context.getLowerer(); |
| } |
| |
| @Override |
| public Replacements getReplacements() { |
| return context.getReplacements(); |
| } |
| |
| @Override |
| public AnchoringNode getCurrentGuardAnchor() { |
| return guardAnchor; |
| } |
| |
| @Override |
| public GuardingNode createGuard(FixedNode before, LogicNode condition, DeoptimizationReason deoptReason, DeoptimizationAction action) { |
| return createGuard(before, condition, deoptReason, action, JavaConstant.NULL_POINTER, false); |
| } |
| |
| @Override |
| public StampProvider getStampProvider() { |
| return context.getStampProvider(); |
| } |
| |
| @Override |
| public GuardingNode createGuard(FixedNode before, LogicNode condition, DeoptimizationReason deoptReason, DeoptimizationAction action, JavaConstant speculation, boolean negated) { |
| if (OptEliminateGuards.getValue()) { |
| for (Node usage : condition.usages()) { |
| if (!activeGuards.isNew(usage) && activeGuards.isMarked(usage) && ((GuardNode) usage).isNegated() == negated) { |
| return (GuardNode) usage; |
| } |
| } |
| } |
| StructuredGraph graph = before.graph(); |
| if (!condition.graph().getGuardsStage().allowsFloatingGuards()) { |
| FixedGuardNode fixedGuard = graph.add(new FixedGuardNode(condition, deoptReason, action, speculation, negated)); |
| graph.addBeforeFixed(before, fixedGuard); |
| DummyGuardHandle handle = graph.add(new DummyGuardHandle(fixedGuard)); |
| fixedGuard.lower(this); |
| GuardingNode result = handle.getGuard(); |
| handle.safeDelete(); |
| return result; |
| } else { |
| GuardNode newGuard = graph.unique(new GuardNode(condition, guardAnchor, deoptReason, action, negated, speculation)); |
| if (OptEliminateGuards.getValue()) { |
| activeGuards.markAndGrow(newGuard); |
| } |
| return newGuard; |
| } |
| } |
| |
| @Override |
| public FixedWithNextNode lastFixedNode() { |
| return lastFixedNode; |
| } |
| |
| @Override |
| public NodeCostProvider getNodeCostProvider() { |
| return context.getNodeCostProvider(); |
| } |
| |
| private void setLastFixedNode(FixedWithNextNode n) { |
| assert n.isAlive() : n; |
| lastFixedNode = n; |
| } |
| } |
| |
| private final CanonicalizerPhase canonicalizer; |
| private final LoweringTool.LoweringStage loweringStage; |
| |
| public LoweringPhase(CanonicalizerPhase canonicalizer, LoweringTool.LoweringStage loweringStage) { |
| this.canonicalizer = canonicalizer; |
| this.loweringStage = loweringStage; |
| } |
| |
| /** |
| * Checks that second lowering of a given graph did not introduce any new nodes. |
| * |
| * @param graph a graph that was just {@linkplain #lower lowered} |
| * @throws AssertionError if the check fails |
| */ |
| private boolean checkPostLowering(StructuredGraph graph, PhaseContext context) { |
| Mark expectedMark = graph.getMark(); |
| lower(graph, context, LoweringMode.VERIFY_LOWERING); |
| Mark mark = graph.getMark(); |
| assert mark.equals(expectedMark) : graph + ": a second round in the current lowering phase introduced these new nodes: " + graph.getNewNodes(expectedMark).snapshot(); |
| return true; |
| } |
| |
| @Override |
| protected void run(final StructuredGraph graph, PhaseContext context) { |
| lower(graph, context, LoweringMode.LOWERING); |
| assert checkPostLowering(graph, context); |
| } |
| |
| private void lower(StructuredGraph graph, PhaseContext context, LoweringMode mode) { |
| IncrementalCanonicalizerPhase<PhaseContext> incrementalCanonicalizer = new IncrementalCanonicalizerPhase<>(canonicalizer); |
| incrementalCanonicalizer.appendPhase(new Round(context, mode)); |
| incrementalCanonicalizer.apply(graph, context); |
| assert graph.verify(); |
| } |
| |
| /** |
| * Checks that lowering of a given node did not introduce any new {@link Lowerable} nodes that |
| * could be lowered in the current {@link LoweringPhase}. Such nodes must be recursively lowered |
| * as part of lowering {@code node}. |
| * |
| * @param node a node that was just lowered |
| * @param preLoweringMark the graph mark before {@code node} was lowered |
| * @param unscheduledUsages set of {@code node}'s usages that were unscheduled before it was |
| * lowered |
| * @throws AssertionError if the check fails |
| */ |
| private static boolean checkPostNodeLowering(Node node, LoweringToolImpl loweringTool, Mark preLoweringMark, Collection<Node> unscheduledUsages) { |
| StructuredGraph graph = (StructuredGraph) node.graph(); |
| Mark postLoweringMark = graph.getMark(); |
| NodeIterable<Node> newNodesAfterLowering = graph.getNewNodes(preLoweringMark); |
| if (node instanceof FloatingNode) { |
| if (!unscheduledUsages.isEmpty()) { |
| for (Node n : newNodesAfterLowering) { |
| assert !(n instanceof FixedNode) : node.graph() + ": cannot lower floatable node " + node + " as it introduces fixed node(s) but has the following unscheduled usages: " + |
| unscheduledUsages; |
| } |
| } |
| } |
| for (Node n : newNodesAfterLowering) { |
| if (n instanceof Lowerable) { |
| ((Lowerable) n).lower(loweringTool); |
| Mark mark = graph.getMark(); |
| assert postLoweringMark.equals(mark) : graph + ": lowering of " + node + " produced lowerable " + n + " that should have been recursively lowered as it introduces these new nodes: " + |
| graph.getNewNodes(postLoweringMark).snapshot(); |
| } |
| } |
| return true; |
| } |
| |
| private enum LoweringMode { |
| LOWERING, |
| VERIFY_LOWERING |
| } |
| |
| private final class Round extends Phase { |
| |
| private final PhaseContext context; |
| private final LoweringMode mode; |
| private ScheduleResult schedule; |
| private final SchedulePhase schedulePhase; |
| |
| private Round(PhaseContext context, LoweringMode mode) { |
| this.context = context; |
| this.mode = mode; |
| |
| /* |
| * In VERIFY_LOWERING, we want to verify whether the lowering itself changes the graph. |
| * Make sure we're not detecting spurious changes because the SchedulePhase modifies the |
| * graph. |
| */ |
| boolean immutableSchedule = mode == LoweringMode.VERIFY_LOWERING; |
| |
| this.schedulePhase = new SchedulePhase(immutableSchedule); |
| } |
| |
| @Override |
| protected CharSequence getName() { |
| switch (mode) { |
| case LOWERING: |
| return "LoweringRound"; |
| case VERIFY_LOWERING: |
| return "VerifyLoweringRound"; |
| default: |
| throw GraalError.shouldNotReachHere(); |
| } |
| } |
| |
| @Override |
| public boolean checkContract() { |
| /* |
| * lowering with snippets cannot be fully built in the node costs of all high level |
| * nodes |
| */ |
| return false; |
| } |
| |
| @Override |
| public void run(StructuredGraph graph) { |
| schedulePhase.apply(graph, false); |
| schedule = graph.getLastSchedule(); |
| schedule.getCFG().computePostdominators(); |
| Block startBlock = schedule.getCFG().getStartBlock(); |
| ProcessFrame rootFrame = new ProcessFrame(startBlock, graph.createNodeBitMap(), startBlock.getBeginNode(), null); |
| LoweringPhase.processBlock(rootFrame); |
| } |
| |
| private class ProcessFrame extends Frame<ProcessFrame> { |
| private final NodeBitMap activeGuards; |
| private AnchoringNode anchor; |
| |
| ProcessFrame(Block block, NodeBitMap activeGuards, AnchoringNode anchor, ProcessFrame parent) { |
| super(block, parent); |
| this.activeGuards = activeGuards; |
| this.anchor = anchor; |
| } |
| |
| @Override |
| public void preprocess() { |
| this.anchor = Round.this.process(block, activeGuards, anchor); |
| } |
| |
| @Override |
| public ProcessFrame enter(Block b) { |
| return new ProcessFrame(b, activeGuards, b.getBeginNode(), this); |
| } |
| |
| @Override |
| public Frame<?> enterAlwaysReached(Block b) { |
| AnchoringNode newAnchor = anchor; |
| if (parent != null && b.getLoop() != parent.block.getLoop() && !b.isLoopHeader()) { |
| // We are exiting a loop => cannot reuse the anchor without inserting loop |
| // proxies. |
| newAnchor = b.getBeginNode(); |
| } |
| return new ProcessFrame(b, activeGuards, newAnchor, this); |
| } |
| |
| @Override |
| public void postprocess() { |
| if (anchor != null && OptEliminateGuards.getValue()) { |
| for (GuardNode guard : anchor.asNode().usages().filter(GuardNode.class)) { |
| if (activeGuards.isMarkedAndGrow(guard)) { |
| activeGuards.clear(guard); |
| } |
| } |
| } |
| } |
| |
| } |
| |
| @SuppressWarnings("try") |
| private AnchoringNode process(final Block b, final NodeBitMap activeGuards, final AnchoringNode startAnchor) { |
| |
| final LoweringToolImpl loweringTool = new LoweringToolImpl(context, startAnchor, activeGuards, b.getBeginNode()); |
| |
| // Lower the instructions of this block. |
| List<Node> nodes = schedule.nodesFor(b); |
| for (Node node : nodes) { |
| |
| if (node.isDeleted()) { |
| // This case can happen when previous lowerings deleted nodes. |
| continue; |
| } |
| |
| // Cache the next node to be able to reconstruct the previous of the next node |
| // after lowering. |
| FixedNode nextNode = null; |
| if (node instanceof FixedWithNextNode) { |
| nextNode = ((FixedWithNextNode) node).next(); |
| } else { |
| nextNode = loweringTool.lastFixedNode().next(); |
| } |
| |
| if (node instanceof Lowerable) { |
| Collection<Node> unscheduledUsages = null; |
| assert (unscheduledUsages = getUnscheduledUsages(node)) != null; |
| Mark preLoweringMark = node.graph().getMark(); |
| try (DebugCloseable s = node.graph().withNodeSourcePosition(node)) { |
| ((Lowerable) node).lower(loweringTool); |
| } |
| if (loweringTool.guardAnchor.asNode().isDeleted()) { |
| // TODO nextNode could be deleted but this is not currently supported |
| assert nextNode.isAlive(); |
| loweringTool.guardAnchor = AbstractBeginNode.prevBegin(nextNode); |
| } |
| assert checkPostNodeLowering(node, loweringTool, preLoweringMark, unscheduledUsages); |
| } |
| |
| if (!nextNode.isAlive()) { |
| // can happen when the rest of the block is killed by lowering |
| // (e.g. by an unconditional deopt) |
| break; |
| } else { |
| Node nextLastFixed = nextNode.predecessor(); |
| if (!(nextLastFixed instanceof FixedWithNextNode)) { |
| // insert begin node, to have a valid last fixed for next lowerable node. |
| // This is about lowering a FixedWithNextNode to a control split while this |
| // FixedWithNextNode is followed by some kind of BeginNode. |
| // For example the when a FixedGuard followed by a loop exit is lowered to a |
| // control-split + deopt. |
| AbstractBeginNode begin = node.graph().add(new BeginNode()); |
| nextLastFixed.replaceFirstSuccessor(nextNode, begin); |
| begin.setNext(nextNode); |
| nextLastFixed = begin; |
| } |
| loweringTool.setLastFixedNode((FixedWithNextNode) nextLastFixed); |
| } |
| } |
| return loweringTool.getCurrentGuardAnchor(); |
| } |
| |
| /** |
| * Gets all usages of a floating, lowerable node that are unscheduled. |
| * <p> |
| * Given that the lowering of such nodes may introduce fixed nodes, they must be lowered in |
| * the context of a usage that dominates all other usages. The fixed nodes resulting from |
| * lowering are attached to the fixed node context of the dominating usage. This ensures the |
| * post-lowering graph still has a valid schedule. |
| * |
| * @param node a {@link Lowerable} node |
| */ |
| private Collection<Node> getUnscheduledUsages(Node node) { |
| List<Node> unscheduledUsages = new ArrayList<>(); |
| if (node instanceof FloatingNode) { |
| for (Node usage : node.usages()) { |
| if (usage instanceof ValueNode) { |
| if (schedule.getCFG().getNodeToBlock().isNew(usage) || schedule.getCFG().blockFor(usage) == null) { |
| unscheduledUsages.add(usage); |
| } |
| } |
| } |
| } |
| return unscheduledUsages; |
| } |
| } |
| |
| enum ProcessBlockState { |
| ST_ENTER, |
| ST_PROCESS, |
| ST_ENTER_ALWAYS_REACHED, |
| ST_LEAVE, |
| ST_PROCESS_ALWAYS_REACHED; |
| } |
| |
| /** |
| * This state-machine resembles the following recursion: |
| * |
| * <pre> |
| * void processBlock(Block block) { |
| * preprocess(); |
| * // Process always reached block first. |
| * Block alwaysReachedBlock = block.getPostdominator(); |
| * if (alwaysReachedBlock != null && alwaysReachedBlock.getDominator() == block) { |
| * processBlock(alwaysReachedBlock); |
| * } |
| * |
| * // Now go for the other dominators. |
| * for (Block dominated : block.getDominated()) { |
| * if (dominated != alwaysReachedBlock) { |
| * assert dominated.getDominator() == block; |
| * processBlock(dominated); |
| * } |
| * } |
| * postprocess(); |
| * } |
| * </pre> |
| * |
| * This is necessary, as the recursive implementation quickly exceed the stack depth on SPARC. |
| * |
| * @param rootFrame contains the starting block. |
| */ |
| public static void processBlock(final Frame<?> rootFrame) { |
| ProcessBlockState state = ST_PROCESS; |
| Frame<?> f = rootFrame; |
| while (f != null) { |
| ProcessBlockState nextState; |
| if (state == ST_PROCESS || state == ST_PROCESS_ALWAYS_REACHED) { |
| f.preprocess(); |
| nextState = state == ST_PROCESS_ALWAYS_REACHED ? ST_ENTER : ST_ENTER_ALWAYS_REACHED; |
| } else if (state == ST_ENTER_ALWAYS_REACHED) { |
| if (f.alwaysReachedBlock != null && f.alwaysReachedBlock.getDominator() == f.block) { |
| f = f.enterAlwaysReached(f.alwaysReachedBlock); |
| nextState = ST_PROCESS; |
| } else { |
| nextState = ST_ENTER; |
| } |
| } else if (state == ST_ENTER) { |
| if (f.dominated.hasNext()) { |
| Block n = f.dominated.next(); |
| if (n == f.alwaysReachedBlock) { |
| if (f.dominated.hasNext()) { |
| n = f.dominated.next(); |
| } else { |
| n = null; |
| } |
| } |
| if (n == null) { |
| nextState = ST_LEAVE; |
| } else { |
| f = f.enter(n); |
| assert f.block.getDominator() == f.parent.block; |
| nextState = ST_PROCESS; |
| } |
| } else { |
| nextState = ST_LEAVE; |
| } |
| } else if (state == ST_LEAVE) { |
| f.postprocess(); |
| f = f.parent; |
| nextState = ST_ENTER; |
| } else { |
| throw GraalError.shouldNotReachHere(); |
| } |
| state = nextState; |
| } |
| } |
| |
| public static void processBlockBounded(final Frame<?> rootFrame) { |
| ProcessBlockState state = ST_PROCESS; |
| Frame<?> f = rootFrame; |
| while (f != null) { |
| ProcessBlockState nextState; |
| if (state == ST_PROCESS || state == ST_PROCESS_ALWAYS_REACHED) { |
| f.preprocess(); |
| nextState = state == ST_PROCESS_ALWAYS_REACHED ? ST_ENTER : ST_ENTER_ALWAYS_REACHED; |
| } else if (state == ST_ENTER_ALWAYS_REACHED) { |
| if (f.alwaysReachedBlock != null && f.alwaysReachedBlock.getDominator() == f.block) { |
| Frame<?> continueRecur = f.enterAlwaysReached(f.alwaysReachedBlock); |
| if (continueRecur == null) { |
| // stop recursion here |
| f.postprocess(); |
| f = f.parent; |
| state = ST_ENTER; |
| continue; |
| } |
| f = continueRecur; |
| nextState = ST_PROCESS; |
| } else { |
| nextState = ST_ENTER; |
| } |
| } else if (state == ST_ENTER) { |
| if (f.dominated.hasNext()) { |
| Block n = f.dominated.next(); |
| if (n == f.alwaysReachedBlock) { |
| if (f.dominated.hasNext()) { |
| n = f.dominated.next(); |
| } else { |
| n = null; |
| } |
| } |
| if (n == null) { |
| nextState = ST_LEAVE; |
| } else { |
| Frame<?> continueRecur = f.enter(n); |
| if (continueRecur == null) { |
| // stop recursion here |
| f.postprocess(); |
| f = f.parent; |
| state = ST_ENTER; |
| continue; |
| } |
| f = continueRecur; |
| nextState = ST_PROCESS; |
| } |
| } else { |
| nextState = ST_LEAVE; |
| } |
| } else if (state == ST_LEAVE) { |
| f.postprocess(); |
| f = f.parent; |
| nextState = ST_ENTER; |
| } else { |
| throw GraalError.shouldNotReachHere(); |
| } |
| state = nextState; |
| } |
| } |
| |
| public abstract static class Frame<T extends Frame<?>> { |
| protected final Block block; |
| final T parent; |
| Iterator<Block> dominated; |
| final Block alwaysReachedBlock; |
| |
| public Frame(Block block, T parent) { |
| super(); |
| this.block = block; |
| this.alwaysReachedBlock = block.getPostdominator(); |
| this.dominated = block.getDominated().iterator(); |
| this.parent = parent; |
| } |
| |
| public Frame<?> enterAlwaysReached(Block b) { |
| return enter(b); |
| } |
| |
| public abstract Frame<?> enter(Block b); |
| |
| public abstract void preprocess(); |
| |
| public abstract void postprocess(); |
| } |
| |
| } |
