[clang] [AMDGPU][Clang] Support bfloat16 arithmetic for GFX950 and GFX1250. (PR #147541)

[Matt Arsenault via cfe-commits]

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@@ -451,6 +451,8 @@ class LLVM_LIBRARY_VISIBILITY AMDGPUTargetInfo final : public TargetInfo {
         CUMode = false;
       else if (F == "+image-insts")
         HasImage = true;
+      else if (F == "+gfx950-insts" || F == "+gfx1250-insts")
+        HasFullBFloat16 = true;
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arsenm wrote:

This shouldn't really depend on the subtarget 

https://github.com/llvm/llvm-project/pull/147541