[llvm] [ConstantFold] Fold `ilogb` and `ilogbf` when the input parameter is a constant value. (PR #113014)

[Matt Arsenault via llvm-commits]

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@@ -2131,7 +2133,8 @@ static Constant *ConstantFoldScalarCall1(StringRef Name,
     }
 #endif
 
-    if (!Ty->isHalfTy() && !Ty->isFloatTy() && !Ty->isDoubleTy())
+    if (!Ty->isHalfTy() && !Ty->isFloatTy() && !Ty->isDoubleTy() &&
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arsenm wrote:

Probably should just handle this case before here, or just delete the whole check.

This function could use some cleanup. Why isn't this using a switch over the intrinsic ID? 

https://github.com/llvm/llvm-project/pull/113014