Fix a bug where DAGCombine was producing an illegal ConstantFP
node after legalize, and remove the workaround code from the
ARM backend.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78615 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 6119411..42d163f 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -3721,7 +3721,18 @@
// If the input is a constant, let getNode fold it.
if (isa<ConstantSDNode>(N0) || isa<ConstantFPSDNode>(N0)) {
SDValue Res = DAG.getNode(ISD::BIT_CONVERT, N->getDebugLoc(), VT, N0);
- if (Res.getNode() != N) return Res;
+ if (Res.getNode() != N) {
+ if (!LegalOperations ||
+ TLI.isOperationLegal(Res.getNode()->getOpcode(), VT))
+ return Res;
+
+ // Folding it resulted in an illegal node, and it's too late to
+ // do that. Clean up the old node and forego the transformation.
+ // Ideally this won't happen very often, because instcombine
+ // and the earlier dagcombine runs (where illegal nodes are
+ // permitted) should have folded most of them already.
+ DAG.DeleteNode(Res.getNode());
+ }
}
// (conv (conv x, t1), t2) -> (conv x, t2)