Nils Philippsen wrote:
On Tue, 2005-05-10 at 11:30 -0400, Owen Taylor wrote:
On Tue, 2005-05-10 at 08:26 -0400, Jakub Jelinek wrote:
a) on x86-64 this is unnecessary, all x86-64's have -msse2 by default
b) -msse2 implies -msse
c) if you use -msse2 in CFLAGS for all files, you can't run the latest
GIMP on e.g. Pentium2, or pre-x86_64 AMD chips.
-msse2 should be ONLY used on sources that have SSE/SSE2 stuff in it,
and GIMP should make sure that no routine from those sources will be
ever called on pre-SSE2 chips
This sounds like a big pain ... shouldn't there be a way to say
"use sse2/sse only for builtins" ?
Without that, there is no way to use builtins in single functions; you
need to have one file for sse2, one for sse, one for mmx, and do the
detection of the current processor somewhere else entirely.
I concur, with gcc <= 4.0.0-2 it was possible to use MMX/SSE calls in
inline assembly without having to use -mmmx/-msse/-msse2. In order to
build the gimp so that it uses MMX/SSE where available, I had to resort
to serious autofoo munging because it doesn't allow for setting
per-object compiler flags.
Nils
why aren't sse/mmx/sse2 enabled by default on x86_64 ? all those chips
supports it.
--
fedora-devel-list mailing list
fedora-devel-list@xxxxxxxxxx
http://www.redhat.com/mailman/listinfo/fedora-devel-list
