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

[Stanislav Mekhanoshin via llvm-commits]

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@@ -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
+// CHECK: v_dot2_bf16_bf16 v5, v1, v2, 0x42c8 ; encoding: [0x05,0x00,0x67,0xd6,0x01,0x05,0xfe,0x03,0xc8,0x42,0x00,0x00]
+
+v_dot2_bf16_bf16 v5, v1, v2, 1.0
+// v_dot2_bf16_bf16 v5, v1, v2, 0x3f80 ; encoding: [0x05,0x00,0x67,0xd6,0x01,0x05,0xfe,0x03,0x80,0x3f,0x00,0x00]
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rampitec wrote:

FYI: this shall be inline literal. I.e:
    0xd6672005
    0x03ca0501

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