[libc] [llvm] [APFloat] Add exp function for APFloat::IEEESsingle using expf implementation from LLVM libc. (PR #143959)

[via llvm-commits]

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@@ -1522,6 +1522,7 @@ class APFloat : public APFloatBase {
   friend int ilogb(const APFloat &Arg) { return ilogb(Arg.getIEEE()); }
   friend APFloat scalbn(APFloat X, int Exp, roundingMode RM);
   friend APFloat frexp(const APFloat &X, int &Exp, roundingMode RM);
+  friend APFloat exp(const APFloat &X, roundingMode RM);
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lntue wrote:

Fixed.  And added test for using the default rounding mode.

https://github.com/llvm/llvm-project/pull/143959