[PATCH] D51582: [IndVars] Turn isValidRewrite into an assertion

[Andrew Trick via Phabricator via llvm-commits]

atrick added a comment.

`isValidRewrite` is a hack that wasn't supposed to live this long.

At the IR level, the problem is simply that we don't want to rewrite

`gep Base, (&p[n] - &p[0])`

as

`gep &p[n], Base - &p[0]`

SCEV no longer does the kind of reassociation. I'm not sure when it was fixed, but the original test case definitely no longer requires the `isValidRewrite` check.


https://reviews.llvm.org/D51582