[11] RFR(M): 8203915: Induction variable of over-unrolled loop conflicts with range checks

[Tobias Hartmann]

Hi Vladimir,

thanks for looking at this!

On 07.06.2018 19:18, Vladimir Kozlov wrote:
> Can you look if PhaseIdealLoop::do_range_check() is executed for main loop in this case? If array
> length is known statically that code should produce check which should eliminate control flow for
> main loop and collapse it.

PhaseIdealLoop::do_range_check() is not executed because after predication, the main loop does not
contain any range checks (the predicates are before the pre-loop).

The tests work fine without loop predication (-XX:-UseLoopPredicate) because in this case
do_range_check() is executed and the corresponding check eliminates control flow as expected.

Thanks,
Tobias