-> BlockId -- ^ id of the current block, for debugging.
-> [LiveInstr] -- ^ liveness annotated instructions in this block.
- -> RegM ( [Instr] -- ^ instructions after register allocation
- , [NatBasicBlock]) -- ^ fresh blocks of fixup code.
+ -> RegM ( [Instr] -- instructions after register allocation
+ , [NatBasicBlock]) -- fresh blocks of fixup code.
linearRA _ accInstr accFixup _ []