| From | Linus Torvalds <> | Date | Tue, 24 Apr 2012 14:18:09 -0700 | Subject | Re: [RFC][PATCH 0/3] gcc work-around and math128 |
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On Tue, Apr 24, 2012 at 2:15 PM, Andy Lutomirski <luto@amacapital.net> wrote: > > I played with some of this stuff awhile ago, and for timekeeping, it > seemed like a 64x32->96 bit multiply followed by a right shift was > enough, and that operation is a lot faster on 32-bit architectures than > a full 64x64->128 multiply.
Ack. That may sound like odd numbers, but 64x32->96 sounds sane. And I think it avoids a multiply even on 64-bit, no?
Linus
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