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  1. JDK
  2. JDK-8236181

C2: Remove useless step_over_gc_barrier() in int->bool conversion

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    • b05
    • generic
    • generic

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        In cfgnode.cpp, in is_x2logic() that converts a diamond-shape if/else to simple bool patterns, we have a step_over_gc_barrier() at the end. This has been introduced by Shenandoah. I believe the intention was to convert obj vs null check to a simple boolean expression and eliminate the barrier on the unneeded path. However, it is not needed because Shenandoah we already eliminate barriers when the only user is a null-check, and it might actually be counter-productive if the barrier is needed on other paths, because it keeps the input of the barrier alive. This is probably a left-over from pre-LRB.

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                rkennke Roman Kennke
                rkennke Roman Kennke
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