Enforcing a profile available check in the driver does not work with
incremental LTO builds where the LTO backend invocation does not include
the profile flags. At this point the profiles have already been consumed
and the IR contains profile metadata. Instead we always pass through the
-fsplit-machine-functions flag on user request. The pass itself contains
a check to return early if no profile information is available.
Differential Revision: https://reviews.llvm.org/D87943
This patch adds a command line flag for the machine function splitter
(added in rG94faadaca4e1).
-fsplit-machine-functions
Split machine functions using profile information (x86 ELF). On
other targets an error is emitted. If profile information is not
provided a warning is emitted notifying the user that profile
information is required.
Differential Revision: https://reviews.llvm.org/D87047