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How can we avoid this stall?

• Predict branch taken

  Benchmark studies show 53% taken

  Doesn't really work in DLX - we don't know the destination address

• Predict branch not taken (47%)
  • Don't stall - execute next instruction
  • But ``squash'' it if branch turns out to be taken
  • i.e. block memory access and WB
  • Luckily these come late in pipeline in DLX