RFR: 8301489: ShortLoopOptimizer might lift instructions before their inputs

[Daniel Skantz]

ShortLoopOptimizer might lift instructions before their inputs on some graph shapes. We propose adding a check that the insertion point for an instruction that is a candidate for hoisting should not be higher up the dominator tree than any inputs to the instruction.

Testing: tier1-tier3.

Additional testing: observed that `(cur_invariant && !v.is_valid())` never occurs on tier1-tier3 before the added test case.
Also verified that the depth check is equivalent to `(*vp->block() == _insert->block()) || dominates(*vp, _insert)` on all of tier1-tier3.

Failure case: in the attached image the `arraylength` instruction from B10 is lifted to B0, as the dominator of B10 is calculated as B0. This is based on the logic in [`ComputeLinearScanOrder::compute_dominator_impl`](https://github.com/openjdk/jdk/blob/master/src/hotspot/share/c1/c1_IR.cpp#L801).  But the array input is in Block 3. This is later spotted in `c1_LIRAssembler.cpp` with `Error: ShouldNotReachHere()`. We can reproduce the error on other instructions too -- the reader may refer to the test case provided.

![image](https://github.com/openjdk/jdk/assets/111436254/9130516c-073d-45d1-a38a-af776e5e6672)

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Commit messages:
 - latest
 - fix compileonly
 - Remove unecessary Xbatch
 - Tweak comment
 - WIP close
 - WIP
 - WIP with some checks
 - WIP fix with validation

Changes: https://git.openjdk.org/jdk/pull/14492/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=14492&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8301489
  Stats: 143 lines in 2 files changed: 142 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/14492.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/14492/head:pull/14492

PR: https://git.openjdk.org/jdk/pull/14492