JDK-8282045 : When loop strip mining fails, safepoints are removed from loop anyway
  • Type: Bug
  • Component: hotspot
  • Sub-Component: compiler
  • Affected Version: 11,17,18,19
  • Priority: P5
  • Status: Resolved
  • Resolution: Fixed
  • Submitted: 2022-02-17
  • Updated: 2022-04-04
  • Resolved: 2022-03-01
The Version table provides details related to the release that this issue/RFE will be addressed.

Unresolved : Release in which this issue/RFE will be addressed.
Resolved: Release in which this issue/RFE has been resolved.
Fixed : Release in which this issue/RFE has been fixed. The release containing this fix may be available for download as an Early Access Release or a General Availability Release.

To download the current JDK release, click here.
JDK 17 JDK 19
17.0.4-oracleFixed 19 b12Fixed
Related Reports
Relates :  
JDK-8281322 - C2: always construct strip mined loop initially (even if strip mining is disabled)
Relates :  
JDK-8186027 - C2: loop strip mining
Relates :  
JDK-8283451 - C2: assert(_base == Long) failed: Not a Long
Description
I noticed that if loop strip mining fails because a safepoint is not found right above the exit test following partial peel for instance, all safepoints are removed from the loop anyway.
Comments
A pull request was submitted for review. URL: https://git.openjdk.java.net/jdk18u/pull/89 Date: 2022-04-04 07:19:02 +0000
04-04-2022
Fix Request (JDK 18u) Fixes incorrect removal of safepoints from counted loops. The fix is low risk and applies cleanly (except a minor conflict due to changes to surrounding code). The fix was already backported to JDK 17u. Tier 1-3 testing is running for JDK 18u.
04-04-2022
A pull request was submitted for review. URL: https://git.openjdk.java.net/jdk17u-dev/pull/312 Date: 2022-03-30 10:53:22 +0000
30-03-2022
Fix Request (17u): Should get backported for parity with 17.0.4-oracle. Skara recognizes it as clean (IRNode.java has different context). Test has passed.
30-03-2022
Changeset: 2c5d266f Author: Roland Westrelin <roland@openjdk.org> Date: 2022-03-01 14:43:05 +0000 URL: https://git.openjdk.java.net/jdk/commit/2c5d266f9f20005bc2a6c30dcaa95b059ea59d74
01-03-2022
ILW = mostly unnoticed impact; likelihood unclear; disable stripmining = LMM = P5
17-02-2022
A pull request was submitted for review. URL: https://git.openjdk.java.net/jdk/pull/7513 Date: 2022-02-17 10:00:32 +0000
17-02-2022