[jdk11u-dev] RFR: 8284944: assert(cnt++ < 40) failed: infinite cycle in loop optimization

[Goetz Lindenmaier]

I backport this for parity with 11.0.17-oracle.
I had to resolve compile.cpp because of a space difference in the context.

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

Commit messages:
 - Backport 796494d0fecfb9587e8b68ff1d5c09411cb82f89

Changes: https://git.openjdk.org/jdk11u-dev/pull/1200/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=1200&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8284944
  Stats: 128 lines in 2 files changed: 125 ins; 2 del; 1 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/1200.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev pull/1200/head:pull/1200

PR: https://git.openjdk.org/jdk11u-dev/pull/1200