On Wed, Mar 05, 2008, Colin Percival wrote: > Bruce Evans wrote: > > Modified files: > > sys/i386/include _types.h > > Log: > > Change float_t and double_t to long double on i386. > > Doesn't this have a rather severe performance impact on any code which > uses double_t?
Yes, if the code is compiled with -msse2. Otherwise, doubles get fed to the i387 anyway. On Thu, Mar 06, 2008, Peter Jeremy wrote: > npx.h currently defines __INITIAL_NPXCW__ as 0x127f which makes the x87 > emulate double (53-bit) precision rather than its native 64-bit long > double. Doesn't this change also need a corresponding change to npx.h > to make the x87 run with 64-bit precision? Technically Bruce's change isn't wrong without changing the default precision, it's just rather pointless. (Why tell programs to store variables in a wider format if you're just going to evaluate them in a narrower format anyway?) So I guess I agree that if we're going to go down this path, we ought to just bite the bullet and change npx.h and contrib/gcc/config/i386/freebsd.h to use 64-bit precision by default on i386. _______________________________________________ cvs-all@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/cvs-all To unsubscribe, send any mail to "[EMAIL PROTECTED]"
