[jdk11u-dev] RFR: 8281811: assert(_base == Tuple) failed: Not a Tuple after JDK-8280799 [v3]

[Roland Westrelin]

> This change doesn't apply cleanly. It requires a GC API method that's not available in 11. There's already adhoc code for shenandoah in PhaseIdealLoop::build_and_optimize() to replace the missing API call. The backported patch uses the same logic. Tested with tier1 and the patch's test case (fails without the fix, passes with it).

Roland Westrelin has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains three additional commits since the last revision:

 - Merge branch 'master' into backport-8281811
 - Backport fcce24c5b3cd1dab755fd9b6779af71f4dd78773
 - Backport 1ef45c5bbdeb4e1ca65c6d8f3ac1568a6951f3a7

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

Changes:
  - all: https://git.openjdk.java.net/jdk11u-dev/pull/1049/files
  - new: https://git.openjdk.java.net/jdk11u-dev/pull/1049/files/00ea7ad2..aa851948

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk11u-dev&pr=1049&range=02
 - incr: https://webrevs.openjdk.java.net/?repo=jdk11u-dev&pr=1049&range=01-02

  Stats: 4617 lines in 93 files changed: 2803 ins; 1202 del; 612 mod
  Patch: https://git.openjdk.java.net/jdk11u-dev/pull/1049.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk11u-dev pull/1049/head:pull/1049

PR: https://git.openjdk.java.net/jdk11u-dev/pull/1049