[llvm-branch-commits] [clang] [flang] [llvm] [openmp] [Flang] Move builtin .mod generation into runtimes (Reapply #137828) (PR #171515)

[Michael Kruse via llvm-branch-commits]

Meinersbur wrote:

> Let me try the patches on my side. Do you plan to merge them in a particular order or/and merge them at the same time?

#171610 first, then this one. 

#171610 is nearly NFC since it only moves some CMake code from flang-rt/CMakeLists.txt into runtimes/CMakeLists.txt and introduces defintions that will only be used in this PR. "Nearly" because it does make CMake check the Fortran compiler earlier in more situtions than flang-rt alone would have. Also, it introduces the `RUNTIMES_DEVICE_ARCHITECTURES` configuration parameter which is used if `FLANG_RT_DEVICE_ARCHITECTURES` is not set.

https://github.com/llvm/llvm-project/pull/171515