After LGTM and Check-all
Vector-reduction arithmetic accepts vectors as inputs and produces
scalars as outputs.This class of vector operation forms the basis
of many scientific computations. In vector-reduction arithmetic,
the evaluation off is independent of the order of the input elements of V.
Reviewer: 1. craig.topper
2. igorb
Differential Revision: https://reviews.llvm.org/D25988
llvm-svn: 285493