Static schemes (c’ed)

• Prediction depends on the direction of branch

  • Backward-Taken-Forward-Not-Taken (BTFNT)
  • With the same assumptions as before, contribution to the CPI
    0.25 (0.33 * 1 + 0.66 * 0. 5* 2 + 0.66 * 0.5 * 0) = 0.25
    (the first term corresponds to backward taken and the next two to forward not-taken)

• Prediction based on opcode

  • A bit in the opcode for prediction T/NT (can be set after profiling the application)
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