[Python-Dev] String hash function multiplier

Andrew MacIntyre 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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