[prev in list] [next in list] [prev in thread] [next in thread] 

List:       linux-m68k
Subject:    [RFC PATCH 0/2] Improve m68k __mulsi3
From:       "George Spelvin" <linux () horizon ! com>
Date:       2016-05-11 10:22:48
Message-ID: 20160511102248.1447.qmail () ns ! horizon ! com
[Download RAW message or body]

As part of some other work I was doing looking at constant multiplies
on various platforms, and that led to looking a the em68k __mulsi3 code.

Which in turn led to the following microoptimizations.  Note that this
is desk-checked but UNTESTED, thus the RFC nature of the patches.

A bit of cleverness uses the available A0 and A1 registers to
save three instruction words one memory fetch, shaving 16 cycles
off the code.
--
To unsubscribe from this list: send the line "unsubscribe linux-m68k" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
[prev in list] [next in list] [prev in thread] [next in thread]