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  1. JDK
  2. JDK-8319451

PhaseIdealLoop::conditional_move is too conservative

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      When transforming a Phi into a CMove, the threshold is set to be approximately BlockLayoutMinDiamondPercentage, the reason is given:

      // BlockLayoutByFrequency optimization moves infrequent branch
      // from hot path. No point in CMOV'ing in such case

      This sets the default value of the threshold to be around 18%, which is too conservative. The reason also does not make a lot of sense since the important property which makes jumping expensive is not code layout. We should remove this.

            qamai Quan Anh Mai
            qamai Quan Anh Mai
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