I'm writing a platform-independant library of platform-dependant features. I want to support, at the least, x86-32, x86-64, PPC32, and PPC64. Right now I have the code written for x86-32 (NASM), PPC32 (Metroworks), and PPC64 (Metroworks). Now I need to write the x86-64 versions. I was hoping I could use NASM for this, but I don't see any indication on the NASM site or manual that NASM supports the x86-64 extensions. Are there any plans to add this in the near future, or should I look for another assembler?