Two-level adaptive predictors:Per-address history schemes
The first-level branch history refers to the last k occurrences of the same branch instruction (using self-history only!)
Therefore a BHR is associated with each branch instruction.
The per-address branch history registers are combined in a table that is called per-address branch history table (PBHT).
In the simplest per address history scheme, the BHRs index into a single global PHT. ? denoted as PAg (multiple per-address indexed BHRs, and a single global PHT).