> This PR adresses a missed optimization in `CmpLNode::Ideal`. It occurs when 
> when we encode a pointer comparison as `CmpL(OrL(left, right), 0L)` (which 
> essentially translates to "both operands are null") during parsing in 
> `do_acmp`, and this comparison can later be folded to a constant in 
> `CmpLNode::Ideal` because one of the operands has a `NotNull` type. This 
> optimization hides behind `can_reshape`, so it can only be carried out during 
> IGVN and not during the initial GVN pass.  To fix this, we just need to make 
> sure to add the compare to the worklist during parsing.
> 
> ### Testing
> - [x] GitHub Actions
> - [x] tier1-3, plus some internal testing
> 
> Thank you for reviewing!

Benoît Maillard has updated the pull request incrementally with one additional 
commit since the last revision:

  Missing IgnoreUnrecognizedVMOptions

-------------

Changes:
  - all: https://git.openjdk.org/valhalla/pull/2145/files
  - new: https://git.openjdk.org/valhalla/pull/2145/files/3041036d..90c7e12e

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=valhalla&pr=2145&range=01
 - incr: https://webrevs.openjdk.org/?repo=valhalla&pr=2145&range=00-01

  Stats: 2 lines in 1 file changed: 1 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/valhalla/pull/2145.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/2145/head:pull/2145

PR: https://git.openjdk.org/valhalla/pull/2145

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