0x00B3C000 - 0x00C7A4E0 is code in ROM (Majora's Mask (U) Decompressed)

 

0x800A5AC0 - 0x801E3FA0 is code in RAM (Majora's Mask (U))

Any changes you make in RAM that are in code can be patched to ROM by subtracting 0x7F569AC0 from the address. This is also useful for finding things like Tatl's colours in ROM if you already know their location in RAM.