Mercurial > hg > graal-compiler
view graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/BeginNode.java @ 6546:79119bd2505a
Call target can be null, so don't crash debug printer
author | Christian Wimmer <christian.wimmer@oracle.com> |
---|---|
date | Wed, 10 Oct 2012 20:29:07 -0700 |
parents | feb579677b58 |
children | 4eba1a717254 |
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/* * Copyright (c) 2011, 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 com.oracle.graal.nodes; import static com.oracle.graal.graph.iterators.NodePredicates.*; import java.util.*; import com.oracle.graal.graph.*; import com.oracle.graal.graph.iterators.*; import com.oracle.graal.nodes.spi.*; import com.oracle.graal.nodes.type.*; public class BeginNode extends FixedWithNextNode implements StateSplit, LIRLowerable, Simplifiable, Node.IterableNodeType { @Input(notDataflow = true) private FrameState stateAfter; public FrameState stateAfter() { return stateAfter; } public void setStateAfter(FrameState x) { assert x == null || x.isAlive() : "frame state must be in a graph"; updateUsages(stateAfter, x); stateAfter = x; } public boolean hasSideEffect() { return false; } public BeginNode() { super(StampFactory.dependency()); } public static BeginNode begin(FixedNode with) { if (with instanceof BeginNode) { return (BeginNode) with; } BeginNode begin = with.graph().add(new BeginNode()); begin.setNext(with); return begin; } @Override public void simplify(SimplifierTool tool) { FixedNode prev = (FixedNode) this.predecessor(); if (prev == null) { // This is the start node. } else if (prev instanceof ControlSplitNode) { // This begin node is necessary. } else { // This begin node can be removed and all guards moved up to the preceding begin node. prepareDelete(); tool.addToWorkList(next()); ((StructuredGraph) graph()).removeFixed(this); } } public static BeginNode prevBegin(FixedNode from) { Node prevBegin = from; while (prevBegin != null) { if (prevBegin instanceof BeginNode) { return (BeginNode) prevBegin; } prevBegin = prevBegin.predecessor(); } return null; } public void evacuateGuards(FixedNode evacuateFrom) { if (!usages().isEmpty()) { BeginNode prevBegin = prevBegin(evacuateFrom); assert prevBegin != null; for (Node anchored : anchored().snapshot()) { anchored.replaceFirstInput(this, prevBegin); } } } public void prepareDelete() { prepareDelete((FixedNode) predecessor()); } public void prepareDelete(FixedNode evacuateFrom) { removeProxies(); evacuateGuards(evacuateFrom); } public void removeProxies() { for (ValueProxyNode vpn : proxies().snapshot()) { // can not use graph.replaceFloating because vpn.value may be null during killCFG vpn.replaceAtUsages(vpn.value()); vpn.safeDelete(); } } @Override public boolean verify() { assertTrue(predecessor() != null || this == ((StructuredGraph) graph()).start() || this instanceof MergeNode, "begin nodes must be connected"); return super.verify(); } @Override public void generate(LIRGeneratorTool gen) { // nop } public NodeIterable<GuardNode> guards() { return usages().filter(GuardNode.class); } public NodeIterable<Node> anchored() { return usages().filter(isNotA(ValueProxyNode.class)); } public NodeIterable<ValueProxyNode> proxies() { return usages().filter(ValueProxyNode.class); } public NodeIterable<FixedNode> getBlockNodes() { return new AbstractNodeIterable<FixedNode>() { @Override public Iterator<FixedNode> iterator() { return new BlockNodeIterator(BeginNode.this); } }; } private class BlockNodeIterator implements Iterator<FixedNode> { private FixedNode current; public BlockNodeIterator(FixedNode next) { this.current = next; } @Override public boolean hasNext() { return current != null; } @Override public FixedNode next() { FixedNode ret = current; if (ret == null) { throw new NoSuchElementException(); } if (!(current instanceof FixedWithNextNode) || (current instanceof BeginNode && current != BeginNode.this)) { current = null; } else { current = ((FixedWithNextNode) current).next(); } return ret; } @Override public void remove() { throw new UnsupportedOperationException(); } } }