[llvm] [AMDGPU] Make v2bf16 BUILD_VECTOR legal (PR #92022)

[Matt Arsenault via llvm-commits]

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@@ -55,15 +55,17 @@ define amdgpu_ps float @v_test_cvt_v2f32_v2bf16_s(<2 x float> inreg %src) {
 ; GCN-NEXT:    s_add_i32 s5, s2, 0x7fff
 ; GCN-NEXT:    v_cmp_u_f32_e64 s[2:3], s1, s1
 ; GCN-NEXT:    s_and_b64 s[2:3], s[2:3], exec
-; GCN-NEXT:    s_cselect_b32 s2, s4, s5
+; GCN-NEXT:    s_cselect_b32 s1, s4, s5
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arsenm wrote:

This managed to get worse. Is some combine looking for f16 specifically?

https://github.com/llvm/llvm-project/pull/92022