Revert "[SelectionDAG] Add knownbits support for EXTRACT_VECTOR_ELT opcodes"

This reverts commit r288916 as it is currently causing a crasher in
Halide. Reproducer on llvm.org/PR31323. While it might be that halide is
generating invalid IR, llc shouldn't crash.

llvm-svn: 289194

1 files changed, 0 insertions, 36 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index c6522101f66..f276902d2e6 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -2590,42 +2590,6 @@ void SelectionDAG::computeKnownBits(SDValue Op, APInt &KnownZero,
     }
     break;
   }
-  case ISD::INSERT_VECTOR_ELT: {
-    SDValue InVec = Op.getOperand(0);
-    SDValue InVal = Op.getOperand(1);
-    SDValue EltNo = Op.getOperand(2);
-
-    ConstantSDNode *CEltNo = dyn_cast<ConstantSDNode>(EltNo);
-    if (CEltNo && CEltNo->getAPIntValue().ult(NumElts)) {
-      // If we know the element index, split the demand between the
-      // source vector and the inserted element.
-      KnownZero = KnownOne = APInt::getAllOnesValue(BitWidth);
-      unsigned EltIdx = CEltNo->getZExtValue();
-
-      // If we demand the inserted element then add its common known bits.
-      if (DemandedElts[EltIdx]) {
-        computeKnownBits(InVal, KnownZero2, KnownOne2, Depth + 1);
-        KnownOne &= KnownOne2.zextOrTrunc(KnownOne.getBitWidth());
-        KnownZero &= KnownZero2.zextOrTrunc(KnownZero.getBitWidth());;
-      }
-
-      // If we demand the source vector then add its common known bits, ensuring
-      // that we don't demand the inserted element.
-      APInt VectorElts = DemandedElts & ~(APInt::getOneBitSet(NumElts, EltIdx));
-      if (!!VectorElts) {
-        computeKnownBits(InVec, KnownZero2, KnownOne2, VectorElts, Depth + 1);
-        KnownOne &= KnownOne2;
-        KnownZero &= KnownZero2;
-      }
-    } else {
-      // Unknown element index, so ignore DemandedElts and demand them all.
-      computeKnownBits(InVec, KnownZero, KnownOne, Depth + 1);
-      computeKnownBits(InVal, KnownZero2, KnownOne2, Depth + 1);
-      KnownOne &= KnownOne2.zextOrTrunc(KnownOne.getBitWidth());
-      KnownZero &= KnownZero2.zextOrTrunc(KnownZero.getBitWidth());;
-    }
-    break;
-  }
   case ISD::BSWAP: {
     computeKnownBits(Op.getOperand(0), KnownZero2, KnownOne2, DemandedElts,
                      Depth + 1);