src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/calc/IntegerLessThanNode.java
changeset 54084 84f10bbf993f
parent 52578 7dd81e82d083
child 58299 6df94ce3ab2f
--- a/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/calc/IntegerLessThanNode.java	Tue Mar 12 12:12:01 2019 -0700
+++ b/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/calc/IntegerLessThanNode.java	Tue Mar 12 19:17:42 2019 +0100
@@ -50,6 +50,7 @@
 import jdk.vm.ci.meta.JavaKind;
 import jdk.vm.ci.meta.MetaAccessProvider;
 import jdk.vm.ci.meta.PrimitiveConstant;
+import jdk.vm.ci.meta.TriState;
 
 @NodeInfo(shortName = "<")
 public final class IntegerLessThanNode extends IntegerLowerThanNode {
@@ -225,7 +226,6 @@
                             }
                         }
                     }
-
                 }
             }
 
@@ -296,4 +296,29 @@
             return StampFactory.forInteger(bits, cast(min, bits), cast(max, bits));
         }
     }
+
+    @Override
+    public TriState implies(boolean thisNegated, LogicNode other) {
+        if (!thisNegated) {
+            if (other instanceof IntegerLessThanNode) {
+                ValueNode otherX = ((IntegerLessThanNode) other).getX();
+                ValueNode otherY = ((IntegerLessThanNode) other).getY();
+                // x < y => !y < x
+                if (getX() == otherY && getY() == otherX) {
+                    return TriState.FALSE;
+                }
+            }
+
+            // x < y => !x == y
+            // x < y => !y == x
+            if (other instanceof IntegerEqualsNode) {
+                ValueNode otherX = ((IntegerEqualsNode) other).getX();
+                ValueNode otherY = ((IntegerEqualsNode) other).getY();
+                if ((getX() == otherX && getY() == otherY) || (getX() == otherY && getY() == otherX)) {
+                    return TriState.FALSE;
+                }
+            }
+        }
+        return super.implies(thisNegated, other);
+    }
 }