On Sun, 2012-03-25 at 19:23 +0200, Olof Kindgren wrote: <snip - lots of discussion about how OpenRISC should treat R0>
> I'm still of the opinion that we should hardwire it to zero. I know > that it will theoretically break backwards compatibility, but I would > like to know if this really is an issue. The benefits of hardwiring is > that it will behave like everyone (or at least I) assumed it was > implemented before this discussion, and I guess we don't suffer from > register starvation anyways, so that won't be a problem. We also don't > have to take care about saving and restoring it. I've always liked having R0 hard-wired to zero. Having a destination register that ignored what was written to it was useful. However compiler technology has moved on, and I suspect that it now makes no difference. I've copied amylaar, as local GCC guru, to see if he has any comment. Jeremy -- Tel: +44 (1590) 610184 Cell: +44 (7970) 676050 SkypeID: jeremybennett Email: [email protected] Web: www.embecosm.com _______________________________________________ OpenRISC mailing list [email protected] http://lists.openrisc.net/listinfo/openrisc
