[Python-Dev] String hash function multiplier
andymac at bullseye.apana.org.au
Fri Apr 16 19:36:52 EDT 2004
On Wed, 14 Apr 2004, Jeff Epler wrote:
> imul is on all x86 architectures, but whether to use it or not depends
> on the characteristics of the target CPU. With -mcpu=i386, imul is
> considered quite slow and a shift sequence is (almost?) always preferred
> when one operand is constant. With -mcpu=i686 and newer, imul seems to
> be preferred.
My misunderstanding. I hadn't really comprehended the full extent of
"instruction scheduling" in this context.
Andrew I MacIntyre "These thoughts are mine alone..."
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