Replace the `ident_t` handling in Clang with the methods offered by the
OMPIRBuilder. This cuts down on the clang code as well as the
differences between the two, making further transitions easier. Tests
have changed but there should not be a real functional change. The most
interesting difference is probably that we stop generating local ident_t
allocations for now and just use globals. Given that this happens only
with debug info, the location part of the `ident_t` is probably bigger
than the test anyway. As the location part is already a global, we can
avoid the allocation, memcpy, and store in favor of a constant global
that is slightly bigger. This can be revisited if there are
complications.
Reviewed By: ABataev
Differential Revision: https://reviews.llvm.org/D80735
Before we kept the first applicable `ident_t*` during deduplication of
runtime calls. The problem is that "first" is dependent on the iteration
order of a DenseMap. Since the proper solution, which is to combine the
information from all `ident_t*`, should be deterministic on its own, we
will not try to make the iteration order deterministic. Instead, we will
create a fresh `ident_t*` if there is not a unique existing `ident_t*`
to pick.
If we deduplicate OpenMP runtime calls we have multiple `ident_t*` that
represent information like source location. So far, we simply kept the
one used by the replacement call. However, as exposed by PR44893, that
can cause problems if we have stack allocated `ident_t` objects. While
we need to revisit the use of these as well, it is clear that we
eventually want to merge source location information in some way. With
this patch we add the infrastructure to do so but without doing the
actual merge. Instead we pick a global `ident_t` from the replaced
calls, if possible, or create a new one with an unknown location
instead.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D74925