[PM] Switch the downward invalidation to be incremental where only the
one function's analyses are invalidated at a time. Also switch the
preservation of the proxy to *fully* preserve the lower (function)
analyses.
Combined, this gets both upward and downward analysis invalidation to
a point I'm happy with:
- A function pass invalidates its function analyses, and its parent's
module analyses.
- A module pass invalidates all of its functions' analyses including the
set of which functions are in the module.
- A function pass can preserve a module analysis pass.
- If all function passes preserve a module analysis pass, that
preservation persists. If any doesn't the module analysis is
invalidated.
- A module pass can opt into managing *all* function analysis
invalidation itself or *none*.
- The conservative default is none, and the proxy takes the maximally
conservative approach that works even if the set of functions has
changed.
- If a module pass opts into managing function analysis invalidation it
has to propagate the invalidation itself, the proxy just does nothing.
The only thing really missing is a way to query for a cached analysis or
nothing at all. With this, function passes can more safely request
a cached module analysis pass without fear of it accidentally running
part way through.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195519 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed