[PATCH] D55974: [GVN] Force a sequence point when comparing two DenseMap values.

[Eli Friedman via Phabricator via llvm-commits]

efriedma added a comment.

If we're calling grow() on BlockRPONumber in this code, something has gone wrong. Both "P" and "CurrentBlock" should have an RPO number at this point in the code, so it shouldn't actually grow.

It looks like r225536 added a new caller to performScalarPRE(), and BlockRPONumber is not correctly initialized at that point.  I'm surprised this hasn't led to any miscompiles.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D55974/new/

https://reviews.llvm.org/D55974