threshold-leading-one-detect

8-bit leading one detector. Finds the position of the highest-order 1 bit (MSB priority).

Circuit

x[7:0] ──► LOD ──┬──► pos[2:0]  (position 0-7)
                 └──► valid     (1 if any bit set)

Truth Table (examples)

Input	Binary	Position	Valid
0	00000000	0	0
1	00000001	0	1
2	00000010	1	1
128	10000000	7	1
255	11111111	7	1
170	10101010	7	1

Algorithm

For each bit position i (7 down to 0):
  leader[i] = x[i] AND NOT(any bit j > i is set)

Position is binary encoding of which leader is active.

Architecture

Component	Count	Neurons
Higher-than OR	8	8
NOT higher	8	8
Leader AND	8	8
Position encode	3	3
Valid OR	1	1

Total: 28 neurons, 136 parameters, 3 layers

Applications

• Floating-point normalization: Find exponent adjustment
• Priority encoding: Highest-priority interrupt
• Integer log₂: Position = floor(log₂(x))
• Bit manipulation: Count leading zeros = 7 - position

Usage

from safetensors.torch import load_file

w = load_file('model.safetensors')

# For x = 0b00101100 (44):
# Leading one at position 5
# log₂(44) ≈ 5

Relation to CLZ

Count Leading Zeros = 7 - position (when valid=1)

x = 0b00100000 → position=5 → CLZ=2
x = 0b10000000 → position=7 → CLZ=0

Files

threshold-leading-one-detect/
├── model.safetensors
├── create_safetensors.py
├── config.json
└── README.md

License

MIT