Write ARM assembly implementations for all of the functions below. The functions must be present in a single .s file.

1. uint64_t add64 (uint32_t x, uint32_t y) // returns x + y; worth 10 points

2. uint64_t sub64 (uint64_t x, uint64_t y) // returns x - y

All available conditionals are on page 1-19 (39) of the ARM 7 Reference Manual. Keep in mind that signed and unsigned integers may require different conditionals.