RFR: 8264958: C2 compilation fails with assert "n is later than its clone"

[Tobias Hartmann]

On Fri, 16 Apr 2021 08:36:31 GMT, Roland Westrelin <roland at openjdk.org> wrote:

> JDK-8229483 added logic to hoist a load that would wrongly end up in
> an outer strip mined loop. That logic checks that it's legal to do so
> with:
> 
> is_dominator(n_ctrl, x_head)
> 
> but that test passes for n_ctrl == x_head when it's not legal to hoist
> the load i.e. the test we want is for strict domination. The fix I
> propose is to add an explicit check for that case.

Looks good to me.

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Marked as reviewed by thartmann (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/3539