[X86] detectZextAbsDiff - use SDPatternMatch::m_Abs() matcher. NFC.

Author: RKSimon

llvm/lib/Target/X86/X86ISelLowering.cpp

@@ -46009,11 +46009,9 @@ static bool detectZextAbsDiff(SDValue Abs, SDValue &Op0, SDValue &Op1) {
 
   // Check if the operands of the sub are zero-extended from vectors of i8.
   EVT SrcVT0, SrcVT1;
-  return sd_match(
-             Abs,
-             m_UnaryOp(ISD::ABS,
-                       m_Sub(m_AllOf(m_Value(Op0), m_ZExt(m_VT(SrcVT0))),
-                             m_AllOf(m_Value(Op1), m_ZExt(m_VT(SrcVT1)))))) &&
+  return sd_match(Abs,
+                  m_Abs(m_Sub(m_AllOf(m_Value(Op0), m_ZExt(m_VT(SrcVT0))),
+                              m_AllOf(m_Value(Op1), m_ZExt(m_VT(SrcVT1)))))) &&
          SrcVT0.getVectorElementType() == MVT::i8 &&
          SrcVT1.getVectorElementType() == MVT::i8;
 }