[libc] [llvm] [libc][math][c23] Add {,u}fromfp{,x}{,f,l,f128} functions (PR #86003)

[via llvm-commits]

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@@ -414,6 +420,26 @@ def StdC : StandardSpec<"stdc"> {
           FunctionSpec<"frexpl", RetValSpec<LongDoubleType>, [ArgSpec<LongDoubleType>, ArgSpec<IntPtr>]>,
           GuardedFunctionSpec<"frexpf128", RetValSpec<Float128Type>, [ArgSpec<Float128Type>, ArgSpec<IntPtr>], "LIBC_TYPES_HAS_FLOAT128">,
 
+          FunctionSpec<"fromfp", RetValSpec<DoubleType>, [ArgSpec<DoubleType>, ArgSpec<IntType>, ArgSpec<UnsignedIntType>]>,
+          FunctionSpec<"fromfpf", RetValSpec<FloatType>, [ArgSpec<FloatType>, ArgSpec<IntType>, ArgSpec<UnsignedIntType>]>,
+          FunctionSpec<"fromfpl", RetValSpec<LongDoubleType>, [ArgSpec<LongDoubleType>, ArgSpec<IntType>, ArgSpec<UnsignedIntType>]>,
+          FunctionSpec<"fromfpf128", RetValSpec<LongDoubleType>, [ArgSpec<LongDoubleType>, ArgSpec<IntType>, ArgSpec<UnsignedIntType>]>,
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lntue wrote:

`GuardedFunctionSpec` with `Float128Type`

https://github.com/llvm/llvm-project/pull/86003