[clang] [llvm] [AMDGPU] Implement 'llvm.get.fpenv' and 'llvm.set.fpenv' (PR #83906)

[Matt Arsenault via cfe-commits]

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@@ -6826,6 +6826,10 @@ def warn_floatingpoint_eq : Warning<
   "comparing floating point with == or != is unsafe">,
   InGroup<DiagGroup<"float-equal">>, DefaultIgnore;
 
+def warn_fenv_access : Warning<
+  "floating point environment access without #pragma STDC FENV_ACCESS set ON">,
+  InGroup<DiagGroup<"float-env">>;
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arsenm wrote:

It must be a separate patch 

https://github.com/llvm/llvm-project/pull/83906