Revert r212640, "Add trunc (select c, a, b) -> select c (trunc a), (trunc b) combine."

This caused miscompilation on, at least, x86-64. SExt(i1 cond) confused other optimizations.

llvm-svn: 212708

1 files changed, 0 insertions, 14 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index df273659e49..f6077b07d8d 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -6022,20 +6022,6 @@ SDValue DAGCombiner::visitTRUNCATE(SDNode *N) {
     }
   }
 
-  // trunc (select c, a, b) -> select c, (trunc a), (trunc b)
-  if (N0.getOpcode() == ISD::SELECT) {
-    EVT SrcVT = N0.getValueType();
-    if ((!LegalOperations || TLI.isOperationLegal(ISD::SELECT, SrcVT)) &&
-        TLI.isTruncateFree(SrcVT, VT)) {
-      SDLoc SL(N0);
-      SDValue TruncOp0 = DAG.getNode(ISD::TRUNCATE, SL, VT, N0.getOperand(1));
-      SDValue TruncOp1 = DAG.getNode(ISD::TRUNCATE, SL, VT, N0.getOperand(2));
-      EVT SetCCVT = getSetCCResultType(VT);
-      SDValue Cond = DAG.getSExtOrTrunc(N0.getOperand(0), SL, SetCCVT);
-      return DAG.getNode(ISD::SELECT, SDLoc(N), VT, Cond, TruncOp0, TruncOp1);
-    }
-  }
-
   // Fold a series of buildvector, bitcast, and truncate if possible.
   // For example fold
   //   (2xi32 trunc (bitcast ((4xi32)buildvector x, x, y, y) 2xi64)) to