[OPENMP]Add support for analysis of linear variables and step.
Summary:
Added support for basic analysis of the linear variables and linear step
expression. Linear loop iteration variables must be excluded from this
analysis, only non-loop iteration variables must be analyzed.
Reviewers: NoQ
Subscribers: guansong, cfe-commits, caomhin, kkwli0
Tags: #clang
Differential Revision: https://reviews.llvm.org/D65461
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@368295
91177308-0d34-0410-b5e6-
96231b3b80d8