On Tue, 21 Apr 1998 22:17:55 -0700 (PDT) 
 Jonathan Stone <jonathan@DSG.Stanford.EDU> wrote:

 > I thought one 64-bit assignment would be cheaper than the pointer
 > derefs to get the softc variable, but whatever you think is best.

Does the compiler emit a single 64-bit assignment?  Or two 32-bit
assignments?  It might assign the latter if it inlines the copy,
since the structure will be aligned...

BUT...

To do the copy or assignment, it has to load a pointer to the softc's
timeval into a register... so rather than loading two timeval *'s
into registers, just do one.  Plus, you have to deref a pointer
anyhow to do tv.tv_usec (well, note a C pointer, but you get the idea :-)

Jason R. Thorpe                                       thorpej@nas.nasa.gov
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