Some systems feature dedicated memory within the CPU that records past decisions for various branch instructions executed by the program. This assists in predicting the likelihood of taking a branch. What is this memory called?

The small amount of dedicated memory built into the CPU that maintains a record of previous choices for branch instructions is typically referred to as the "branch target buffer" or "branch history buffer." The purpose of this memory is to aid in predicting whether a branch instruction is likely to be taken or not.

The branch target buffer stores information about the outcomes of recent branch instructions. It may keep track of whether a branch was taken or not taken, and it may also store the target address of the branch. This information is then used by the processor's branch predictor to make more informed predictions about future branch instructions.

The branch target buffer is part of the overall branch prediction mechanism in a processor, which aims to improve instruction execution by predicting the outcome of conditional branches. Predicting branches correctly helps minimize the performance impact of branch instructions, which can introduce pipeline stalls if not predicted accurately.