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Re: qcam on NetBSD
Jani Mattsson writes:
> On Fri, 12 Jan 1996, Russell Nelson wrote:
> >
> > Problem is that the stupid 386 doesn't have a barrel shifter (shifts
> > any number of bits in one cycle).
>
> As far as I know it has, you can do e.g. shl ax, cl or
> shl ax, [8-bit immediate constant] on a 386. This takes
> 3 or 7 cycles depending on if the operand is a register
> or a memory address, as many of the 386 instructions do,
> and it's probably faster on a 486 or a Pentium...
Then hmmm, where is the time spent? Thomas -- are you concluding that
a fair bit of time is spent in the unpacking from a guess or from
profiling?
But this is premature -- as Paul noted. Have to get it all working first.
-russ <nelson@crynwr.com> http://www.crynwr.com/~nelson
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