[clang] [llvm] [mlir] IR: Promote "denormal-fp-math" to a first class attribute (PR #174293)

[Matt Arsenault via cfe-commits]

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@@ -193,7 +206,7 @@ struct DenormalMode {
     return MergedMode;
   }
 
-  inline void print(raw_ostream &OS) const;
+  inline void print(raw_ostream &OS, bool Legacy = true) const;
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arsenm wrote:

This avoids breaking the -cc1 flags. The spelling there is "preserve-sign" not "preservesign"

https://github.com/llvm/llvm-project/pull/174293