Efficient floating-point number handling for dynamically typed scripting languages

Abstract

Typical implementations of dynamically typed languages treat floating-point numbers, or flonums, in a "boxed" form, since those numbers don't fit in a natural machine word if a few bits in the word are reserved for type tags. The naïve implementations allocate every instance of flonums in the heap, thus incur large overhead on numerically intensive computations. Compile-time type inference could eliminate boxing of some flonums, but it would be costly for highly dynamic scripting languages, in which a compiler runs every time a script is executed.