[llvm] [clang] [AMDGPU][GFX12] Add 16 bit atomic fadd instructions (PR #75917)

[Matt Arsenault via cfe-commits]

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@@ -1368,6 +1391,28 @@ def int_amdgcn_struct_ptr_buffer_atomic_cmpswap : Intrinsic<
 // gfx908 intrinsic
 def int_amdgcn_struct_buffer_atomic_fadd : AMDGPUStructBufferAtomic<llvm_anyfloat_ty>;
 def int_amdgcn_struct_ptr_buffer_atomic_fadd : AMDGPUStructPtrBufferAtomic<llvm_anyfloat_ty>;
+// gfx12 intrinsic
+def int_amdgcn_struct_buffer_atomic_fadd_v2bf16 : Intrinsic <
+  [llvm_v2i16_ty],
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arsenm wrote:

Patch to v2bf16 legal is committed, you can now update this to use it

https://github.com/llvm/llvm-project/pull/75917