This patch adds more documentation for the OpenMP offloading driver.
This includes a new file that describes the overall pipeline becuase
that was not previously explained in full elsewhere.
Reviewed By: ABataev
Differential Revision: https://reviews.llvm.org/D118815
This patch introduces a linker wrapper tool that allows us to preprocess
files before they are sent to the linker. This adds a dummy action and
job to the driver stage that builds the linker command as usual and then
replaces the command line with the wrapper tool.
Depends on D116543
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D116544