When `left == right` is known at code generation time, the operands are 
necessarily the same oop, so we can jump directly to `L_oops_equal`. 
This patch changes both x86 and aarch65 to do that.

I also considered emitting `equal_result` and returning early in that case.
I decided not to do that because `LIR_OpSubstitutabilityCheck::emit_code()` 
still appends the slow-path stub after `emit_opSubstitutabilityCheck()` returns.
An early return here would skip binding `op->stub()->continuation()`, leaving 
the appended stub with an unbound continuation label. 

---------
- [x] I confirm that I make this contribution in accordance with the [OpenJDK 
Interim AI Policy](https://openjdk.org/legal/ai).

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

Commit messages:
 - 8386861: [lworld] emit_opSubstitutabilityCheck speedup

Changes: https://git.openjdk.org/valhalla/pull/2628/files
  Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=2628&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8386861
  Stats: 18 lines in 2 files changed: 8 ins; 4 del; 6 mod
  Patch: https://git.openjdk.org/valhalla/pull/2628.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/2628/head:pull/2628

PR: https://git.openjdk.org/valhalla/pull/2628

Reply via email to