[X86] Don't use getZExtValue when we have no idea how large the input elements are.

llvm-svn: 326066

llvm/lib/Target/X86/X86ISelLowering.cpp

@@ -34401,8 +34401,8 @@ static SDValue detectAVGPattern(SDValue In, EVT VT, SelectionDAG &DAG,
       ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op);
       if (!C)
         return false;
-      uint64_t Val = C->getZExtValue();
-      if (Val < Min || Val > Max)
+      const APInt &Val = C->getAPIntValue();
+      if (Val.ult(Min) || Val.ugt(Max))
         return false;
     }
     return true;