Re: Does anyone have a better scm_string_hash ?

[Marius Vollmer]

Allister MacLeod <address@hidden> writes:

> Just for reference, what are the timings on a Pentium for these
> instructions?

I don't know...

> I assume from your pleased comments that
> assign-from-plus-and-multiply is sufficiently fast

"x = h + h*8" is in reality "lea (%edi,%edi,8),%edx" which is not a
general multiply-add.

> I'm curious as to why the last line of the second
> way ends up being h=x+a*1, instead of h=x+a.

It's "lea (%edx,%eax,1),%edi".  Maybe the x86 doesn't have a 3-op add
instruction?

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