This reverts commit 940d0a310d,
effectively reapplying 84e8257937, after
working around the compile errors on the bots that I wasn't seeing
locally. I removed the `constexpr` from `OptionalStorage<FileEntryRef>`
that I had cargo-culted from the generic version, since `FileEntryRef`
isn't relevant in `constexpr` contexts anyway.
The original commit message follows:
Make a few changes to the `FileEntryRef` API in preparation for
propagating it enough to remove `FileEntry::getName()`.
- Allow `FileEntryRef` to degrade implicitly to `const FileEntry*`. This
allows functions currently returning `const FileEntry *` to be updated
to return `FileEntryRef` without requiring all callers to be updated
in the same patch. This helps avoid both (a) massive patches where
many fields and locals are updated simultaneously and (b) noisy
incremental patches where the first patch adds `getFileEntry()` at
call sites and the second patch removes it. (Once `FileEntryRef` is
everywhere, we should remove this API.)
- Change `operator==` to compare the underlying `FileEntry*`, ignoring
any difference in the spelling of the filename. There were 0 users of
the existing function because it's not useful. In case comparing the
exact named reference becomes important, add/test `isSameRef`.
- Add `==` comparisons between `FileEntryRef` and `const FileEntry *`
(compares the `FileEntry*`).
- Customize `OptionalStorage<FileEntryRef>` to be pointer-sized. Add
a private constructor that initializes with `nullptr` and specialize
`OptionalStorage` to use it. This unblocks updating fields in
size-sensitive data structures that currently use `const FileEntry *`.
- Add `OptionalFileEntryRefDegradesToFileEntryPtr`, a wrapper around
`Optional<FileEntryRef>` that degrades to `const FileEntry*`. This
facilitates future incremental patches, like the same operator on
`FileEntryRef`. (Once `FileEntryRef` is everywhere, we should remove
this class.)
- Remove the unncessary `const` from the by-value return of
`FileEntryRef::getName`.
- Delete the unused function `FileEntry::isOpenForTests`.
Note that there are still `FileEntry` APIs that aren't wrapped and I
plan to deal with these separately / incrementally, as they are needed.
Differential Revision: https://reviews.llvm.org/D89834
ac49500cd0