Re: Fast integer arithmetic

[ramsdell@... (John D. Ramsdell)]

> Leo Razoumov wrote:
> > Do you have a quantitative evidence of this?
> > All my anecdotal experience is to the contrary of your statement.
> > Modern CPUs like x86 have very fast FPUs so that arithmetic
> > operations with double is very fast (one cycle or sometimes
> > several ops/cycle with parallel pipelines).

Leo, I haven't performed any measurements, however, it would be very
easy to do so, as I have a version of Lua 5.1.3 that has been patched
with the "Go Long Lua" patch already on my machine.  Is there a
standard numerical Lua benchmark or group of benchmarks that people
use when assessing Lua performance?  You have made me so curious right
now.

> Enrico Colombini <erix@erix.it> wrote:

> You're right, of course. I assumed John is working on a FPU-less CPU (as 
> a I do).

Actually, my environment is a very light weight operating system that
runs inside a virtual machine.  The hardware on which the hypervisor
runs has floating point instructions, but you can't use them because
the operating system doesn't save and restore any floating point
registers between VM context switches.

John