Author: @jurajselep
Date: 2026-09-20
Problem: 4x4 matmul
Cost: 667
IR: best_667.ir
Verifier: best_667.py
SHA-256: 7bf91dafc04584b6ce8f4d4d5e4de917ea426e47d84b413b8a068f78e143d7a3
This submission lowers the 4x4 record from 675 to 667, an improvement of 8 weighted-read units (1.185%). Changes to contraction order, input captures, and storage allocation reduce the total read cost while retaining the classical 64-product formula.
The IR uses 64 multiplications, 48 additions, and 20 copies.
| Read source | Cost |
|---|---|
mul |
319 |
add |
178 |
copy |
102 |
| outputs | 68 |
| total | 667 |
Run from the repository root to verify the frozen IR:
python3 -S matmul/submissions/best_667.py