RFR: 8254998: C2: assert(!n->as_Loop()->is_transformed_long_loop()) failure with -XX:StressLongCountedLoop=1 [v2]

[Roland Westrelin]

> Transformation of a long counted loop into a loop nest with a counted
> loop inner loop happens in 2 passes of loop opts: first the loop nest
> is created and then the inner loop is transformed into a counted
> loop. The assert fires because the second step doesn't have a chance
> to run given the first step was executed as the last loop opts pass
> before running out of allowed loop opts passes. The fix I propose for
> this corner case is to relax the assert to account for this.

Roland Westrelin has updated the pull request incrementally with one additional commit since the last revision:

  test fix

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/735/files
  - new: https://git.openjdk.java.net/jdk/pull/735/files/3e6d0269..913cd877

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=735&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=735&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/735.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/735/head:pull/735

PR: https://git.openjdk.java.net/jdk/pull/735