[clang] [llvm] [RFC][WIP][AMDGPU] Use `bf16` instead of `i16` for bfloat (PR #80908)

[Matt Arsenault via cfe-commits]

================
@@ -0,0 +1,8 @@
+// RUN: llvm-mc -arch=amdgcn -mcpu=gfx1100 -show-encoding %s | FileCheck %s
+// RUN: llvm-mc -arch=amdgcn -mcpu=gfx1200 -show-encoding %s | FileCheck %s
+
+v_dot2_bf16_bf16 v5, v1, v2, 100.0
----------------
arsenm wrote:

does this help with #79369 at all? 

https://github.com/llvm/llvm-project/pull/80908