Yukihiro "Matz" Matsumoto ece641c56f mruby-bigint: optimize to_s with 10^k = 2^k * 5^k factorization ...

use the mathematical identity 10^k = 2^k * 5^k to speed up the
divide-and-conquer decimal string conversion. dividing by 5^k
is faster than dividing by 10^k because 5^k has ~30% fewer bits
(log2(5) ≈ 2.32 vs log2(10) ≈ 3.32). the 2^k component is handled
with fast bit shifts.

benchmarks show 3-8% improvement for large numbers:
- 800K bits: 1.00s -> 0.97s
- 1.6M bits: 3.95s -> 3.84s
- 2.4M bits: 8.79s -> 8.46s

Co-authored-by: Claude <noreply@anthropic.com>

2026-01-12 09:21:32 +09:00

..

bigint.c

mruby-bigint: optimize to_s with 10^k = 2^k * 5^k factorization

2026-01-12 09:21:32 +09:00

bigint.h

misc: fix spelling

2025-05-14 02:01:02 +10:00