1 Jul
2004
1 Jul
'04
7:13 a.m.
On Thu, Jul 01, 2004 at 10:25:51AM +0200, Ruben van Royen wrote:
Hi all,
please note that SSE2 has support for 64bit floats (doubles) and contains an
instruction that truncates to int, irregardless of controlwords. A new enough
gcc with (-march=pentium4 or -msse2) and -mfpmath=sse will use sse instead of
the old fp unit. This has more advantages, since sse math uses normal
registers instead of the stack in the old fp unit.
The disadvantage is of course that it does not run on older processors. I'm
also not sure what level of sse athlon currently supports. The last time I
looked, it only supported sse. This is also good, but it lacks support for
double precision floatingpoint.
Also early gcc3's will often produce code that will give bus errors, or
illigal instructions (I forget which) if you try to execute it.
- Steve