Fun with movsb and prefetch
 

Instead of crossposting, I'll give a link to RCE forum (It's probably a known thing anyway)
woodmann.com/forum/showthread.php?t=7195

this means the processor is buggy?

interesting... but will SEH handler rescue this code?

ah, good old pre-fetch queue. It's been a while...
Now, here is small challenge: Write an assembly program to find out how long is the prefetch queue of your CPU! I used to give this as an exercise to my system-level programming students. Some of them could find the solution in just a few CPU cycles and some crashed like an old Pentium ;)

:confused: Sorry for my terrible English. Why emphasize "old Pentium" ?
p.s. the prog running smoothly with Pentium 4 2.8G w/ HT