A DESCRIPTION OF THE PROBLEM :
Reorder optimizations in addnode so special cases appear before general cases; otherwise the special cases would be never covered.
(a - b) + (c - d) subsumes both (a - b) + (b - c) and (a - b) + (c - a). Therefore (a - b) + (b - c) and (a - b) + (c - a) have to be placed before (a - b) + (c - d) so that they can work.
I have submitted a pull request https://github.com/openjdk/jdk/pull/6752
Reorder optimizations in addnode so special cases appear before general cases; otherwise the special cases would be never covered.
(a - b) + (c - d) subsumes both (a - b) + (b - c) and (a - b) + (c - a). Therefore (a - b) + (b - c) and (a - b) + (c - a) have to be placed before (a - b) + (c - d) so that they can work.
I have submitted a pull request https://github.com/openjdk/jdk/pull/6752