threshold-clz8

8-bit count leading zeros.

Function

clz8(a7, a6, a5, a4, a3, a2, a1, a0) = number of leading zeros from MSB (0-8)

Truth Table (selected rows)

Input	First 1	CLZ	Output
1xxxxxxx	bit 7	0	0000
01xxxxxx	bit 6	1	0001
001xxxxx	bit 5	2	0010
0001xxxx	bit 4	3	0011
00001xxx	bit 3	4	0100
000001xx	bit 2	5	0101
0000001x	bit 1	6	0110
00000001	bit 0	7	0111
00000000	none	8	1000

Architecture

Layer 1: Priority detection from MSB (9 neurons)
  has7 = a7 (MSB is set, clz=0)
  has6_first = a6 AND NOT(a7) (clz=1)
  has5_first = a5 AND NOT(a6) AND NOT(a7) (clz=2)
  ...
  has0_first = a0 AND NOT(a1..a7) (clz=7)
  all_zero = NOT(any bit) (clz=8)

Layer 2: Binary encoding (4 neurons)
  y0 = has6_first OR has4_first OR has2_first OR has0_first
  y1 = has5_first OR has4_first OR has1_first OR has0_first
  y2 = has3_first OR has2_first OR has1_first OR has0_first
  y3 = all_zero

Parameters

Inputs	8
Outputs	4
Neurons	13
Layers	2
Parameters	117
Magnitude	69

Usage

from safetensors.torch import load_file
# See model.py for full implementation

# clz8(1,0,0,0,0,0,0,0) = [0,0,0,0] = 0 (MSB set)
# clz8(0,0,0,0,1,0,0,0) = [0,1,0,0] = 4 (four leading zeros)
# clz8(0,0,0,0,0,0,0,0) = [1,0,0,0] = 8 (all zeros)

License

MIT