[PATCH] D29897: [BypassSlowDivision] Use ValueTracking to simplify run-time checks

[Sanjay Patel via Phabricator via llvm-commits]

spatel added a comment.

In https://reviews.llvm.org/D29897#685056, @jlebar wrote:

> I still do not understand what we are trying to accomplish by writing x86-specific tests for this at all.
>
> This is a 99% target-generic LLVM optimization.  The only target-specific part of this transformation is the bypass width.  Everything else is totally generic and has absolutely nothing to do with the target ISA.


Since this is largely target-independent (which jibes with the fact that no existing tests are changing), then yes, I agree that IR tests are better.

For the other patch, where we're running opt and llc in one RUN line - that's definitely not what we want to see in a regression test. If there are multiple transforms happening, there should be multiple tests to check each step in the process.


https://reviews.llvm.org/D29897