DEX instruction and test
beef up test
DEX instruction and test
beef up test
Rebase onto master to pick up compiler errors and use load_x_register to simplify impl of dec_x. Because load_x_register sets the zero and negative status flags already
pull in the remote version of decrement-x branch? So I can push to it? I have no idea what I'm doing
Remove duplicate test from weird merge pull idk
Make Address take i32 so relative addresses work.
Fix build.
Merge pull request #12 from amw-zero/ark-i32-address

Change implementation of AddressDiff from u16 to i32
Merge pull request #11 from amw-zero/decrement-x

DEX instruction