Aim of register renaming:remove anti and output dependencies dynamically by the processor hardware.
Register renaming is the process of dynamically associating physical registers (rename registers) with the architectural registers (logical registers) referred to in the instruction set of the architecture.
- mapping table;
- a new physical register is allocated for every destination register specified in an instruction.
Each physical register is written only once after each assignment from the free list of available registers.
If a subsequent instruction needs its value, that instruction must wait until it is written (true data dependence).