The 48-bit operations of BITAND, BITOR, BITXOR, BITLSHIFT and BITRSHIFT. Operands are below 2⁴⁸ (the engine checks that) and shifts are at most 53 places.
BITAND
BITOR
BITXOR
BITLSHIFT
BITRSHIFT
a & b
a | b
x · 2ⁿ
u128
x / 2ⁿ
x
a ^ b