For the latest documentation on Visual Studio 2017 RC, see Visual Studio 2017 RC Documentation.
Calculates the arctangent of the top value on the stack.
void __cdecl _CIatan();
This version of the
atan function has a specialized calling convention that the compiler understands. It speeds up the execution because it prevents copies from being generated and helps with register allocation.
The resulting value is pushed onto the top of the stack.