[llvm] AMDGPU: Make bf16/v2bf16 legal types (PR #76215)

[Pierre van Houtryve via llvm-commits]

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@@ -1021,13 +1021,19 @@ define half @fmed3_f32_fpext_bf16(bfloat %arg0, bfloat %arg1, bfloat %arg2) #1 {
 ; GFX8-LABEL: fmed3_f32_fpext_bf16:
 ; GFX8:       ; %bb.0:
 ; GFX8-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; GFX8-NEXT:    v_lshlrev_b32_e32 v0, 16, v0
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Pierre-vh wrote:

Why do we have these now?

https://github.com/llvm/llvm-project/pull/76215