Hello NTdebuggers, I'm very impressed with the depth of the answers we are seeing from our readers. As I stated in last week's response, this week's puzzler is going to be harder. With that said let's take it up a notch. One of the things that is really cool about be an Escalation Engineer in GES/CPR is how far we go in the pursuit of solving complex problems. If we're debugging some Microsoft code in a kernel dump or user mode, and our quest takes us into a binary that we don't have code or symbols for, we don't stop, we forge on! Over the years there are members of our team that have had to port to or support Alpha, PowerPC, MIPs, IA64 and x64, myself included. As a result most of us have books for just about every mainstream processor under the sun. It's a good idea if you're going to be debugging on these platforms to have general working knowledge the CPUs you will encounter. The most common CPU's we deal with are x86, followed by x64 and IA64. Microsoft doesn't support PPC, MIPS or Alpha anymore unless you're dealing with Xbox consoles, and those are PPC. That said, this week's challenge is to tell us what the following assembly does. You can tell us in C, or break it down and comment on the various sections.