This patch implements the code generation to use OpenMP 5.0 declare mapper (a.k.a. user-defined mapper) constructs.
Patch written by Lingda Li.
Differential Revision: https://reviews.llvm.org/D67833
only.
Added support for -fopenmp-simd option that allows compilation of
simd-based constructs without emission of OpenMP runtime calls.
llvm-svn: 321560