Messages in this thread | | | From | David Laight <> | Subject | RE: [PATCH] riscv: select ARCH_HAS_FAST_MULTIPLIER | Date | Wed, 22 Nov 2023 11:16:23 +0000 |
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... > 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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