[PATCH] D21710: AMDGPU/R600: Add PatFrags for selecting the correct vtx id for loads

[Matt Arsenault via llvm-commits]

arsenm added a comment.

In http://reviews.llvm.org/D21710#467269, @jvesely wrote:

> In http://reviews.llvm.org/D21710#467057, @arsenm wrote:
>
> > LGTM, but I still thinking checking GetUnderlyingObject for selection is broken. It should at least check for it returning null which is common
>
>
> What are the problems with GetUnderLyingObject? Don't CLC restrictions shield us from potentially failing cases (the only objects are initialized in constant AS)?
>
> with or without renaming the instructions LGTM.


You could loop over them and have an unanalyzed select or phi on the pointer which will fail to find the object. It also has a search depth lint, and it's a pretty heavyweight check for a select pattern


http://reviews.llvm.org/D21710