[X86] In X86DAGToDAGISel::PreprocessISelDAG, make sure we don't access N after we delete it.
If we turn X86ISD::AND into ISD::AND, we delete N. But we were continuing onto the next block of code even though N no longer existed.
Just happened to notice it. I assume asan didn't notice it because we explicitly unpoison deleted nodes and give them a DELETE_NODE opcode.
llvm-svn: 335787
diff --git a/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp b/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp
index 754e74c..3382ee8 100644
--- a/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp
+++ b/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp
@@ -668,6 +668,7 @@
CurDAG->ReplaceAllUsesOfValueWith(SDValue(N, 0), Res);
++I;
CurDAG->DeleteNode(N);
+ continue;
}
if (OptLevel != CodeGenOpt::None &&