Changed u64v handshake reads to u32v with an inline zero-extending
upcast. Clang -Oz now emits 104 bytes, exactly matching vendor's 104
bytes, with 26 instructions on both sides. Three semantic-equivalent
byte differences remain (register allocation, tst-form, test width)
that aren't closable from C alone — need armclang or inline asm.
Matching-decomp verdict for this function: semantic equivalence +
size identity + instruction-count identity = the practical ceiling.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
marfrit
9c20eb0135