CIL has some instructions such as ldc.r8 <float64 (num)>, ldc.r4 <float32 (num)>, ldc.i8 <int64 (num)>, ldc.i4.s <int8 (num)> that are load constants into the stack.
Well, what are the equivalent for these data types (int32, int64, float32, float64) in C#?
See also the data type summary.