Win64/AMD64 API

As far as I know, there is no offical document yet decribing the win64/amd64 api so the follow information is collected from several sources.

Parameter passing

The parameters are passed in a different manner to subroutines than known from amd64/linux.

Integer parameters

The first four parameters are passed in rcx, rdx, r8 and r9. Further parameters are passed on the stack, they are always aligned to 8 byte boundaries regardless of their size. The caller always reserves space on the stack for the parameters passed in registers.