[jdk17] RFR: 8267988: C2: assert(!addp->is_AddP() || addp->in(AddPNode::Base)->is_top() || addp->in(AddPNode::Base) == n->in(AddPNode::Base)) failed: Base pointers must match (addp 1301)

[Roland Westrelin]

This was already reviewed under:

https://github.com/openjdk/jdk/pull/4387

but needs to be fixed to 17

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

Commit messages:
 - review
 - review
 - merge
 - review
 - review
 - fix

Changes: https://git.openjdk.java.net/jdk17/pull/51/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk17&pr=51&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8267988
  Stats: 149 lines in 8 files changed: 86 ins; 1 del; 62 mod
  Patch: https://git.openjdk.java.net/jdk17/pull/51.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk17 pull/51/head:pull/51

PR: https://git.openjdk.java.net/jdk17/pull/51