  For piecewise-smooth differential systems, in this paper we focus on crossing
limit cycles and sliding loops bifurcating from a grazing loop connecting one
high multiplicity tangent point. For the low multiplicity cases considered in
previous publications, the method is to define and analyze return maps
following the classic idea of Poincar\'e. However, high multiplicity leads to
that either domains or properties of return maps are unclear under
perturbations. To overcome these difficulties, we unfold grazing loops by
functional parameters and functional functions, and analyze this unfolding
along some specific parameter curve. Relationships between multiplicity and the
numbers of crossing limit cycles and sliding loops are given, and our results
not only generalize the results obtained in [J. Differential Equations
255(2013), 4403-4436; 269(2020), 11396-11434], but also are new for some
specific grazing loops.
