Add precise per-operation cost analysis from comparing our Kotlin
implementation with bitcoin-core/secp256k1's C source:
- doublePoint: 1,516 insns (Kotlin) vs 530 insns (C) = 2.9×
- mul/sqr accounts for 76% of gap (UMULH+MUL+carry vs single MUL)
- add/neg/half accounts for 24% (reduceSelf vs lazy magnitude tracking)
- Update performance numbers to Java 21 results (verify 3.4×, sign 1.1×)
- Document all optimizations implemented during this session
- Note that lazy reduction penalty (4.2× on cheap ops) is the main
remaining algorithmic opportunity, but requires 5×52-bit limb change
https://claude.ai/code/session_01BhU63WUe9AhikZxRdw3Lpg
Claude
2bf911379f