[Ffmpeg-devel] int vs. float: Hard Numbers

Michael Niedermayer michaelni
Fri May 20 21:07:52 CEST 2005


On Friday 20 May 2005 20:44, Diego Biurrun wrote:
> On Fri, May 20, 2005 at 12:13:24PM -0600, Mike Melanson wrote:
> > 	If anyone wants the code for these tests, let me know.
> Please post the code so it can be reviewed.  We can then run the benchmarks
> on a variety of machines and put an end to this issue once and for all.

if it where so simple ...
but it isnt, the code is flawed and wont tell you much usefull
the first problem is that its all executed just once, so the code wont be in 
the code cache, practically no speed critical piece of code would be executed 
just once ...
the second problem is that every instruction uses the result of the previous, 
while this gives one interresting value for comparission we should also 
meassure how fast cpus are if the instructions dont depend upon each other


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