ARM-64 assembly implementation of encoding/decoding 64-bit integers (unsigned long long int) from/to zero-terminated ASCII strings for a given base (base 2 ... base 85)
Uses the Base 85 alphabet (RFC 1924) which includes the base32hex (base 32 extended hexadecimal) alphabet (RFC 2938):
0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz!#$%&()*+-;<=>?@^_`{|}~
Base 16: Hexadecimal characters above 9 are always expected in upper case.
Programmed on a RaspberryPi 4 (Broadcom BCM2711, Quad core Cortex-A72 (ARM v8) 64-bit SoC @ 1.5GHz) with Ubuntu Mate linux.