Revert "Working up to implicit register"

This reverts commit 36416f8d1bb992f9ffbc9facc165043afc88db03.
Revert "Revert "Working up to implicit register""

This reverts commit 4421f05b8ef687616102c477e9e5ccd8d4e1e6b7.
Merge remote-tracking branch 'origin/master'