The Question is:
Does a compiler for DCL exist? If so what is the performance gain?
The Answer is :
Interpreted languages do not always compile particularly well, and the
syntax and the syntactic capabilities of DCL in particular do not lend
to an easy compilation (or to a full implementation of DCL) -- the
substitution capabilities in particular make the creation of a full
DCL compiler very difficult.
The OpenVMS Wizard has heard of a few DCL compilers over the past
decades, but has not worked with one -- if you cannot afford the
level of overhead of DCL (and there are ways to reduce the overhead
of DCL processing such as the DCLDIET tool used within OpenVMS
Engineering), the usual approach involves executable images and other
languages. (C or Perl, for instance...)