[clang] [llvm] [Clang][AMDGPU] Add __builtin_amdgcn_cvt_off_f32_i4 (PR #133741)

[Matt Arsenault via llvm-commits]

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@@ -140,6 +140,7 @@ BUILTIN(__builtin_amdgcn_cvt_pknorm_u16, "E2Usff", "nc")
 BUILTIN(__builtin_amdgcn_cvt_pk_i16, "E2sii", "nc")
 BUILTIN(__builtin_amdgcn_cvt_pk_u16, "E2UsUiUi", "nc")
 BUILTIN(__builtin_amdgcn_cvt_pk_u8_f32, "UifUiUi", "nc")
+BUILTIN(__builtin_amdgcn_cvt_off_f32_i4, "fUi", "nc")
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arsenm wrote:

It's a 4 bit signed int, so why unsigned? 

https://github.com/llvm/llvm-project/pull/133741