The four share one quadratic interpolator: 128 segments picked by the top
7 bits of the input, each with a constant, a linear and a squared-term
coefficient, and a squarer on the top 10 bits of the rest that rounds t^2
up to a multiple of 256. 128 small coefficient sets per function
replace the 1 MB of delta tables. Derived from the output of the
table-based code, and bit-exact with it over every 32-bit input.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
