## Developed by Yeh and Patt at the same time (1992) as the correlation-based prediction scheme.

## The basic two-level predictor uses a single global branch history register (BHR) of k bits to index in a pattern history table (PHT) of 2-bit counters.

## Global history schemes correspond to correlation-based predictor schemes.

## Example for the notation: GAg:

- a single global BHR (denoted G) and
- a single global PHT (denoted g),
- A stands for adaptive.

## All PHT implementations of Yeh and Patt use 2-bit predictors.

## GAg-predictor with a 4-bit BHR length is denoted as GAg(4).

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