[vorbis-dev] optimization patches

[Taral]

On 31 Aug, Segher Boessenkool wrote:

> I added -mno-ieee-fp to the compile flags; I _think_ fabs() is ok in
> this case. I'll test; no ieee is a huge speedup on x86 anyway.

Really? I see: (gcc version 2.95.3 19991030)

(code)

d = fabs(d);
if (d < 4) ...

(without -mno-ieee-fp)

fldl ...
fabs
fstl ...
fcompl ...
fnstsw ax
and ah, 0x45
cmp ah, 0x1
jne ...

(with -mno-ieee-fp)

fldl ...
fabs
fstl ...
fcompl ...
fnstsw ax
test eax, 0x100
je ...

Not really a huge difference, is it?

Taral


-- 
Taral <taral at taral.net>
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