[PATCH] D40701: [ARM][AArch64][DAG] Reenable post-legalize store merge

[Nirav Dave via Phabricator via llvm-commits]

niravd added a comment.

In https://reviews.llvm.org/D40701#944097, @efriedma wrote:

> > Looking at LegalizeDAG, when we expand a TruncStore we do it as a store of a truncate which IIUC is strictly bitvector-level interpretation.
>
> Yes, the LegalizeDAG code will likely crash on a float TruncStore (but they don't show up outside of x86, so probably nobody noticed).  But the intent is pretty clear if you look at how the x86 backend lowers them. There's also a comment in SelectionDAGNodes.h.  But anyway, it's obscure enough that it probably doesn't matter if you disable the optimization.


Weird. Post-legalized store for X86 has been turned on since early August. I'm surprised we didn't run into a bug sooner.


https://reviews.llvm.org/D40701