AMD64 Multi-Precision Arithmetic

Eric Bainville - Dec 2006

These pages relate my experiments on 64-bit multi-precision arithmetic running on Athlon 64 processors. See the introduction for further details.

Here are the best timings I could get so far:

Functionglibcgmpthis page
Z ← 0 0.50-0.50
Z ← op Z (not neg) --1.13
Z ← X 1.50-1.50
Z ← Z op X (+ - and or xor) -2.001.50
Z ← Z op not X (and or xor) --1.50
Z ← Z * k -3.003.00
Z ← Z * k op X (+ -) -3.133.13
Z ← Z << k -2.502.25
Z ← Z / k -22.0017.00

glibc refers to glibc 4.2, and gmp to gmp 4.2.1 with P. Gaudry's patch.