[PATCH] D93523: [DSE] Use correct memory location for read clobber check

[Florian Hahn via Phabricator via llvm-commits]

fhahn added inline comments.


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Comment at: llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp:1944
     // Find the next clobbering Mod access for DefLoc, starting at StartAccess.
+    Optional<MemoryLocation> CurrentLoc;
     do {
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nikic wrote:
> fhahn wrote:
> > nikic wrote:
> > > fhahn wrote:
> > > > Can this just be `MemoryLocation CurrentLoc`? We should skip the case when it would be `None` and it should always be `!= None` before after the loop.
> > > This uses Optional<MemoryLocation> because getLocForWriteEx() returns it that way. Should I copy it into a separate non-Optional variable after the check that it is not None?
> > I'd put the result of `getLocForWriteEx` into a new temprary and move the content to `CurrentLoc` after the check. Or have something like 
> > 
> > ```
> > if (auto Loc = getLocForWriteEx(....)) {
> >   CurrentLoc = *Loc;
> > } else {
> >   StepAgain = true;
> >   ....
> >   continue;
> > }
> > ```
> I liked your second suggestion. Does the new version look fine?
that looks good, thanks!


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D93523/new/

https://reviews.llvm.org/D93523