how to mod an array of uint64_t, please help

Hi everyone,

I have two array of uint64_t values: a and b.

For example:

a={0x0B922A5894CCBA66ULL,0x1860C1FA43DFA1D6ULL,0x0 A2C46E6F566C8BBULL}
b={0x8FA3193D212CB2F5ULL,0x2DDEF46FE756F455ULL,0xC B0A47DEE5C190EAULL}

I want to compute:

c=a mod b.
It should be done in GF(2).

What should I do? Thank you so much.