[Flang] Options to lower math intrinsics to relaxed, precise variants
Enable lowering to the relaxed and precise variants in the pgmath
library.
This is part of the upstreaming effort from the fir-dev branch in [1].
[1] https://github.com/flang-compiler/f18-llvm-project
Co-authored-by: Eric Schweitz <eschweitz@nvidia.com>
Co-authored-by: Jean Perier <jperier@nvidia.com>
Co-authored-by: Peter Klausler <pklausler@nvidia.com>
Reviewed By: clementval
Differential Revision: https://reviews.llvm.org/D122484