[llvm] [AMDGPU][True16][CodeGen] minmax pattern only for GFX11+ (PR #130786)

[Matt Arsenault via llvm-commits]

arsenm wrote:

> Hi Matt. We only test this minmax pattern in GFX11plus as we should.

There should be negative tests for these patterns on other targets to guard against this sort of issue

> 
> This is fixing an issue that this pattern is not guarded by GFX11plus predicate by mistake. It's very much like a NFC, but not completely

Yes, which means the pattern will mis-select on other targets. Which is very much not NFC and needs a test 

https://github.com/llvm/llvm-project/pull/130786