RE: [PATCH] riscv: select ARCH_HAS_FAST_MULTIPLIER

[David Laight]

...
> However, the
> situation exists on x86 too, for example, P4 doesn't have fast
> integer multiplies ...

P4 doesn't have fast anything :-)

More interestingly does anything modern not have fast multiplies?
(that you'd consider running Linux on).

The silicon required isn't that big.
IIRC an 'n' bit multiplier requires n^2 full adders and has
the latency of 2n adders.

	David

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