From: Eric Botcazou <ebotca...@adacore.com> Date: Mon, 15 Dec 2014 22:27:38 +0100
>> I think it would be reasonable to have gcc targetting ultrasparc >> extensions by default in sparc64-*-linux*. WDYT? > > No strong opinion. FreeBSD and OpenBSD already do it so why not? > > DaveM, any opinion? Keep in mind that some early Niagara chips lacked some portion of the VIS instructions and they are thus emulated in software. The other problem is that the instruction scheduling for "ultrasparc" is either completely unnecessary or wrong for all of the Niagara variants. In fact, 'ultrasparc' is the most complicated and resource intensive of all of the instruction schedulers we have yet it applies to a very small percentage of the actual chips still in use. The "ultrasparc3" scheduler is much smaller and much more efficient, and provides a schedule that works well across all chip variants.
