[llvm] Constant Fold Logf128 calls (PR #84501)

[Matt Arsenault via llvm-commits]

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@@ -289,6 +289,10 @@ class ConstantFP final : public ConstantData {
   /// host double and as the target format.
   static Constant *get(Type *Ty, double V);
 
+#ifdef __FLOAT128__
+  static Constant *get128(Type *Ty, float128 V);
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arsenm wrote:

Just use the APFloat version for float128? 

https://github.com/llvm/llvm-project/pull/84501