V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

XPC
       X Performance Characterization [group] (GPC, X-Windows)


The Free On-line Dictionary of Computing (30 December 2018):

XPC

   eXplicitly Parallel C.

   A dialect of Parallel C which is efficiently compilable to
   both SIMD and MIMD architectures.  Only research
   implementations exist.

   ["Toward Semantic Self-Consistency in Explicitly Parallel
   Languages," M.J. Phillip & H.G. Dietz, Proc 4th Intl Conf on
   Supercomputing, Santa Clara, CA, May 1989, v.1, pp.398-407].

   (1994-12-01)