[llvm] AMDGPU: Add peephole opt baseline tests (PR #161309)

[Frederik Harwath via llvm-commits]

================
@@ -80,3 +80,151 @@ body:             |
     %4:vreg_128 = REG_SEQUENCE %3.sub0, %subreg.sub0, %3.sub1, %subreg.sub1, %3.sub2, %subreg.sub2, %3.sub3, %subreg.sub3
     KILL implicit %4
 ...
+
+---
----------------
frederik-h wrote:

Perhaps add a comment that those tests document missed fold?

https://github.com/llvm/llvm-project/pull/161309