1 files changed, 1 insertions, 45 deletions

diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index 8ed95d5412e..15f4f06a12d 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -14367,7 +14367,6 @@ const char *X86TargetLowering::getTargetNodeName(unsigned Opcode) const {
   case X86ISD::OR:                 return "X86ISD::OR";
   case X86ISD::XOR:                return "X86ISD::XOR";
   case X86ISD::AND:                return "X86ISD::AND";
-  case X86ISD::BZHI:               return "X86ISD::BZHI";
   case X86ISD::BEXTR:              return "X86ISD::BEXTR";
   case X86ISD::MUL_IMM:            return "X86ISD::MUL_IMM";
   case X86ISD::PTEST:              return "X86ISD::PTEST";
@@ -18453,40 +18452,13 @@ static SDValue PerformAndCombine(SDNode *N, SelectionDAG &DAG,
   if (R.getNode())
     return R;
 
-  // Create BEXTR and BZHI instructions
-  // BZHI is X & ((1 << Y) - 1)
+  // Create BEXTR instructions
   // BEXTR is ((X >> imm) & (2**size-1))
   if (VT == MVT::i32 || VT == MVT::i64) {
     SDValue N0 = N->getOperand(0);
     SDValue N1 = N->getOperand(1);
     SDLoc DL(N);
 
-    if (Subtarget->hasBMI2()) {
-      // Check for (and (add (shl 1, Y), -1), X)
-      if (N0.getOpcode() == ISD::ADD && isAllOnes(N0.getOperand(1))) {
-        SDValue N00 = N0.getOperand(0);
-        if (N00.getOpcode() == ISD::SHL) {
-          SDValue N001 = N00.getOperand(1);
-          assert(N001.getValueType() == MVT::i8 && "unexpected type");
-          ConstantSDNode *C = dyn_cast<ConstantSDNode>(N00.getOperand(0));
-          if (C && C->getZExtValue() == 1)
-            return DAG.getNode(X86ISD::BZHI, DL, VT, N1, N001);
-        }
-      }
-
-      // Check for (and X, (add (shl 1, Y), -1))
-      if (N1.getOpcode() == ISD::ADD && isAllOnes(N1.getOperand(1))) {
-        SDValue N10 = N1.getOperand(0);
-        if (N10.getOpcode() == ISD::SHL) {
-          SDValue N101 = N10.getOperand(1);
-          assert(N101.getValueType() == MVT::i8 && "unexpected type");
-          ConstantSDNode *C = dyn_cast<ConstantSDNode>(N10.getOperand(0));
-          if (C && C->getZExtValue() == 1)
-            return DAG.getNode(X86ISD::BZHI, DL, VT, N0, N101);
-        }
-      }
-    }
-
     // Check for BEXTR.
     if ((Subtarget->hasBMI() || Subtarget->hasTBM()) &&
         (N0.getOpcode() == ISD::SRA || N0.getOpcode() == ISD::SRL)) {
@@ -18504,22 +18476,6 @@ static SDValue PerformAndCombine(SDNode *N, SelectionDAG &DAG,
       }
     } // BEXTR
 
-    // Check for BZHI with contiguous mask: (and X, 0x0..0f..f)
-    // This should be checked after BEXTR - when X is a shift, a BEXTR is
-    // preferrable.
-    if (VT == MVT::i64 && Subtarget->hasBMI2()) {
-      if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(N1)) {
-        uint64_t Mask = C->getZExtValue();
-        if (isMask_64(Mask)) {
-          unsigned LZ = CountTrailingOnes_64(Mask);
-          // Only use BZHI for immediates that are too large for an AND:
-          if (LZ > 32)
-            return DAG.getNode(X86ISD::BZHI, DL, VT, N0,
-                               DAG.getConstant(LZ, MVT::i8));
-        }
-      }
-    }
-
     return SDValue();
   }