# HG changeset patch
# User Michael Van De Vanter  <michael.van.de.vanter@oracle.com>
# Date 1398882479 25200
# Node ID 625f779255a73391af07dde2c3e757986df4a5f6
# Parent  3774b6f4319b16566d4e4b412e42ee45c04721b0# Parent  cb2eef41371c7e61e16c0076b0a1ad855dab86cc
Merge with cb2eef41371c7e61e16c0076b0a1ad855dab86cc

diff -r 3774b6f4319b -r 625f779255a7 graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/PiNode.java
--- a/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/PiNode.java	Tue Apr 29 12:43:27 2014 -0700
+++ b/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/PiNode.java	Wed Apr 30 11:27:59 2014 -0700
@@ -74,6 +74,9 @@
         if (stamp() == StampFactory.forNodeIntrinsic()) {
             return false;
         }
+        if (stamp() instanceof ObjectStamp && object.stamp() instanceof ObjectStamp) {
+            return updateStamp(((ObjectStamp) object.stamp()).castTo((ObjectStamp) stamp()));
+        }
         return updateStamp(stamp().join(object().stamp()));
     }
 
diff -r 3774b6f4319b -r 625f779255a7 graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/extended/UnsafeCastNode.java
--- a/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/extended/UnsafeCastNode.java	Tue Apr 29 12:43:27 2014 -0700
+++ b/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/extended/UnsafeCastNode.java	Wed Apr 30 11:27:59 2014 -0700
@@ -60,21 +60,30 @@
     }
 
     @Override
-    public boolean inferStamp() {
-        if (stamp() instanceof ObjectStamp && object.stamp() instanceof ObjectStamp) {
-            return updateStamp(((ObjectStamp) object.stamp()).castTo((ObjectStamp) stamp()));
-        }
-        return updateStamp(object.stamp().join(stamp()));
-    }
-
-    @Override
     public Node canonical(CanonicalizerTool tool) {
         assert getKind() == Kind.Object && object.getKind() == Kind.Object;
-        if (stamp().equals(object.stamp())) {
-            return object;
-        } else {
+
+        ObjectStamp my = (ObjectStamp) stamp();
+        ObjectStamp other = (ObjectStamp) object.stamp();
+
+        if (my.type() == null || other.type() == null) {
+            return this;
+        }
+        if (my.isExactType() && !other.isExactType()) {
             return this;
         }
+        if (my.nonNull() && !other.nonNull()) {
+            return this;
+        }
+        if (!my.type().isAssignableFrom(other.type())) {
+            return this;
+        }
+        /*
+         * The unsafe cast does not add any new type information, so it can be removed. Note that
+         * this means that the unsafe cast cannot be used to "drop" type information (in which case
+         * it must not be canonicalized in any case).
+         */
+        return object;
     }
 
     @Override
diff -r 3774b6f4319b -r 625f779255a7 graal/com.oracle.graal.truffle/src/com/oracle/graal/truffle/nodes/typesystem/UnsafeTypeCastMacroNode.java
--- a/graal/com.oracle.graal.truffle/src/com/oracle/graal/truffle/nodes/typesystem/UnsafeTypeCastMacroNode.java	Tue Apr 29 12:43:27 2014 -0700
+++ b/graal/com.oracle.graal.truffle/src/com/oracle/graal/truffle/nodes/typesystem/UnsafeTypeCastMacroNode.java	Wed Apr 30 11:27:59 2014 -0700
@@ -29,7 +29,6 @@
 import com.oracle.graal.graph.spi.*;
 import com.oracle.graal.nodes.*;
 import com.oracle.graal.nodes.calc.*;
-import com.oracle.graal.nodes.extended.*;
 import com.oracle.graal.truffle.nodes.asserts.*;
 import com.oracle.truffle.api.*;
 
@@ -62,7 +61,7 @@
             }
             Stamp stamp = StampFactory.declared(lookupJavaType, nonNullArgument.asConstant().asInt() != 0);
             ConditionAnchorNode valueAnchorNode = graph().add(new ConditionAnchorNode(CompareNode.createCompareNode(graph(), Condition.EQ, conditionArgument, ConstantNode.forBoolean(true, graph()))));
-            UnsafeCastNode piCast = graph().unique(new UnsafeCastNode(objectArgument, stamp, valueAnchorNode));
+            PiNode piCast = graph().unique(new PiNode(objectArgument, stamp, valueAnchorNode));
             this.replaceAtUsages(piCast);
             return valueAnchorNode;
         }