Mercurial > hg > graal-compiler
diff graal/com.oracle.truffle.api/src/com/oracle/truffle/api/nodes/Node.java @ 12494:57b8a41c0e18
Truffle: fix possible node rewrite failures after recursive calls.
author | Andreas Woess <andreas.woess@jku.at> |
---|---|
date | Sun, 20 Oct 2013 03:26:03 +0200 |
parents | c0c616fe3588 |
children | b7c8b843dc7b |
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--- a/graal/com.oracle.truffle.api/src/com/oracle/truffle/api/nodes/Node.java Sun Oct 20 01:00:02 2013 +0200 +++ b/graal/com.oracle.truffle.api/src/com/oracle/truffle/api/nodes/Node.java Sun Oct 20 03:26:03 2013 +0200 @@ -170,7 +170,6 @@ * @param reason a description of the reason for the replacement * @return the new node */ - @SuppressWarnings({"unchecked"}) public final <T extends Node> T replace(T newNode, String reason) { if (this.getParent() == null) { throw new IllegalStateException("This node cannot be replaced, because it does not yet have a parent."); @@ -180,13 +179,35 @@ newNode.assignSourceSection(sourceSection); } onReplace(newNode, reason); - return (T) this.getParent().replaceChild(this, newNode); + ((Node) newNode).parent = this.parent; + if (!NodeUtil.replaceChild(this.parent, this, newNode)) { + fixupTree(); + } + return newNode; } - private <T extends Node> T replaceChild(T oldChild, T newChild) { - NodeUtil.replaceChild(this, oldChild, newChild); - adoptChild(newChild); - return newChild; + /** + * Rewrite has failed; the tree is likely inconsistent, so fix any stale parent references. + * + * This is a rather expensive operation but rare to occur. + */ + private void fixupTree() { + Node rootNode = NodeUtil.findParent(this, RootNode.class); + if (rootNode == null) { + throw new UnsupportedOperationException("Tree does not have a root node."); + } + rootNode.fixupChildren(); + } + + private void fixupChildren() { + for (Node child : getChildren()) { + if (child != null) { + if (child.parent != this) { + child.parent = this; + } + child.fixupChildren(); + } + } } /**