RFR: 8343148: C2: Refactor uses of "PhaseValue::*con*() + PhaseIdealLoop::set_ctrl()" into separate method [v2]

[theoweidmannoracle]

> This patch introduces the methods `PhaseIdealLoop::intcon` and `PhaseIdealLoop::longcon` which are wrappers for:
> 
> 
> ConINode* node = _igvn.intcon(i);
> set_ctrl(node, C->root());
> 
> 
> and
> 
> 
> ConLNode* node = _igvn.longcon(i);
> set_ctrl(node, C->root());
> 
> 
> Occurrences of this pattern in loopnode.cpp were replaced with the appropriate call to the new methods.

theoweidmannoracle has updated the pull request incrementally with three additional commits since the last revision:

 - Update src/hotspot/share/opto/loopopts.cpp
   
   Co-authored-by: Emanuel Peter <emanuel.peter at oracle.com>
 - Update src/hotspot/share/opto/loopopts.cpp
   
   Co-authored-by: Emanuel Peter <emanuel.peter at oracle.com>
 - Update src/hotspot/share/opto/loopTransform.cpp
   
   Co-authored-by: Emanuel Peter <emanuel.peter at oracle.com>

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/21836/files
  - new: https://git.openjdk.org/jdk/pull/21836/files/38d5bd0d..d1817ee8

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=21836&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=21836&range=00-01

  Stats: 3 lines in 2 files changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/21836.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21836/head:pull/21836

PR: https://git.openjdk.org/jdk/pull/21836