PTX is more or less the same as x86. What's even better is that unlike x86, Nvidia allows you to see and step through the SASS instructions which PTX compiles i

PTX is more or less the same as x86. What's even better is that unlike x86, Nvidia allows you to see and step through the SASS instructions which PTX compiles into. Although SASS is not documented, seeing it alongside the PTX makes it possible to infer the meaning. In contrast to this you can't see the micro-ops running on x86 cpus (although people have inferred quite a lot about them).