On Sat, Jul 24, 2010 at 2:53 AM, Aurelien Jarno <aurel...@aurel32.net> wrote: > On Fri, Jul 23, 2010 at 08:59:54PM +0900, Jun Koi wrote: >> Hi, >> >> I am looking at the save_globals() of TCG code, and it seems this >> function saves regular registers like EAX, ..., EDI back to CPU state. >> >> But I am not sure if it also saves value of other registers, like >> EFlags, Segments, CR*, DR*, ... (?) >> From what I saw, it doesnt seem to do so. Is it correct? >> > > save_globals() is run before calling a function that can trigger a CPU > exception, to make sure that in that case all TCG variables are synced > with the CPU state.
Is it correct? I always assume that save_globals() is also called at end of each block. > > Given the CPU state only uses "normal" registers, there is no need to > save the other registers. Why do you say that CPU state includes only normal registers, given that, like on x86, CPUState has also segs[], cr[] and dr[]? Another question: if save_globals() only saves regular registers, where Qemu saves other registers like segs[], cr[]? Or do they always sync, all the time? Finally, how about Eflags? I remember that Eflags is "lazy sync", but does it sync at end of each block? Thanks, Jun
