[llvm] [AMDGPU][GISel] Notify GISel observers when splitting trap blocks (PR #219128)

[Keshav Vinayak Jha via llvm-commits]

================
@@ -34,6 +35,9 @@ body: |
 ---
 name: test_def_fallthrough_after_trap
 body: |
+  ; CSE: CSEInfo::Add MI: %1:_(p1) = G_CONSTANT i64 0
+  ; CSE: CSEInfo::Recording new MI %1:_(p1) = G_CONSTANT i64 0
+  ; CSE: CSEInfo::Recording new MI %1:_(p1) = G_CONSTANT i64 0
----------------
keshavvinayak01 wrote:

Thanks for the review!

I added a test that runs the CSE-enabled combiner after legalization, which can then verify each entry using the instruction's current parent MBB. Also added a second live instruction so both loops would use > 1 instruction.

https://github.com/llvm/llvm-project/pull/219128