Em 30 de julho de 2011 02:48, Jon Masters <jcm@xxxxxxxxxx> escreveu: > On Sat, 2011-07-30 at 00:37 -0300, Paulo César Pereira de Andrade wrote: > >> I did not do any performance measures so far, so >> forgive me if the extra "vmov d#, r#,r#" or "vmov r#,r#, d#" >> is too costly, but I think it should be worth the >> compatibility with rpms for armv5 or earlier. It should >> have been already discussed at fedora, but I really >> do not know the real reason :-) > >> But have already rebuilt some of the "bootstrap" mandriva >> packages, rpm5, etc, as well as have packages built for >> armv5 installed. This way, rebuilding for armv7 is an >> "optimization", and have something to start with... > > If you're arguing that one could build support for soft float and have > hard float as an option, I must point out that the reason we're doing > things as we are is that the hard floating point requirement forms part > of an ABI switch that we are making concurrent with the bringup. The I am saying that I find the softfp option more appealing *if* not also switching to thumb instruction set. From gcc.info: "`softfp' allows the generation of code using hardware floating-point instructions, but still uses the soft-float calling conventions". This allows armv5 packages, to work because they use the same calling convention, and the abi difference is only that it now pass/return values in vfp registers, and, to conform to abi, should use only two registers anyway. > newer ABI is intentionally incompatible, but can be thought of as an > architecture revision since we're requiring v7+ at the same time. > > We don't have years of ARM backward compatibility to worry about, so now > is the time to move to the newer ABI, which everyone else is moving to > at the same time. Once we're super successful and famous, and a primary > architecture with millions of users, then we can worry about any changes > we might make in the future. At this stage Fedora ARM doesn't have the > history to justify putting off making a switch, and we'll keep a v5 > build of the packages around for those who want that longer term. > > Jon. Paulo _______________________________________________ arm mailing list arm@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/arm
