RFR: 8361702: C2: assert(is_dominator(compute_early_ctrl(limit, limit_ctrl), pre_end)) failed: node pinned on loop exit test?

[Roland Westrelin]

A node in a pre loop only has uses out of the loop dominated by the
loop exit. `PhaseIdealLoop::try_sink_out_of_loop()` sets its control
to the loop exit projection. A range check in the main loop has this
node as input (through a chain of some other nodes). Range check
elimination needs to update the exit condition of the pre loop with an
expression that depends on the node pinned on its exit: that's
impossible and the assert fires. This is a variant of 8314024 (this
one was for a node with uses out of the pre loop on multiple paths). I
propose the same fix: leave the node with control in the pre loop in
this case.

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Commit messages:
 - tests
 - fix

Changes: https://git.openjdk.org/jdk/pull/26424/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=26424&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8361702
  Stats: 178 lines in 4 files changed: 160 ins; 7 del; 11 mod
  Patch: https://git.openjdk.org/jdk/pull/26424.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26424/head:pull/26424

PR: https://git.openjdk.org/jdk/pull/26424