hg: jdk/sandbox: 8210215: C2 should optimize trichotomy calculations

[chris.hegarty at oracle.com]

Changeset: ad6384355aa3
Author:    thartmann
Date:      2018-10-16 14:17 +0200
URL:       http://hg.openjdk.java.net/jdk/sandbox/rev/ad6384355aa3

8210215: C2 should optimize trichotomy calculations
Summary: Ideal transformation to optimize trichotomic comparisons.
Reviewed-by: kvn, jrose

! src/hotspot/share/opto/cfgnode.cpp
! src/hotspot/share/opto/cfgnode.hpp
! src/hotspot/share/opto/subnode.cpp
! src/hotspot/share/opto/subnode.hpp
+ test/hotspot/jtreg/compiler/codegen/TestTrichotomyExpressions.java