--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.graal.compiler.test/src/com/oracle/graal/compiler/test/FloatOptimizationTest.java	Mon Jun 23 14:38:42 2014 -0700
@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package com.oracle.graal.compiler.test;
+
+import org.junit.*;
+
+/**
+ * Check for incorrect elimination of 0.0 and -0.0 from computations. They can affect the sign of
+ * the result of an add or substract.
+ */
+public class FloatOptimizationTest extends GraalCompilerTest {
+
+    @Test
+    public void test1() {
+        test("test1Snippet", -0.0);
+    }
+
+    @SuppressWarnings("all")
+    public static double test1Snippet(double x) {
+        return x + 0.0;
+    }
+
+    @Test
+    public void test2() {
+        test("test2Snippet", -0.0f);
+    }
+
+    @SuppressWarnings("all")
+    public static double test2Snippet(float x) {
+        return x + 0.0f;
+    }
+
+    @Test
+    public void test3() {
+        test("test3Snippet", -0.0);
+    }
+
+    @SuppressWarnings("all")
+    public static double test3Snippet(double x) {
+        return x - -0.0;
+    }
+
+    @Test
+    public void test4() {
+        test("test4Snippet", -0.0f);
+    }
+
+    @SuppressWarnings("all")
+    public static double test4Snippet(float x) {
+        return x - -0.0f;
+    }
+
+    @Override
+    protected void assertDeepEquals(String message, Object expected, Object actual, double delta) {
+        if (expected instanceof Double && actual instanceof Double) {
+            double e = (double) expected;
+            double a = (double) actual;
+            if (Double.doubleToRawLongBits(a) != Double.doubleToRawLongBits(e)) {
+                Assert.fail((message == null ? "" : message) + "raw double bits not equal " + Double.doubleToRawLongBits(a) + " != " + Double.doubleToRawLongBits(e));
+            }
+        } else {
+            super.assertDeepEquals(message, expected, actual, delta);
+        }
+    }
+}

--- a/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/calc/FloatAddNode.java	Mon Jun 23 18:30:49 2014 +0200
+++ b/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/calc/FloatAddNode.java	Mon Jun 23 14:38:42 2014 -0700
@@ -55,12 +55,8 @@
         }
         if (x().isConstant()) {
             return ConstantNode.forPrimitive(evalConst(x().asConstant(), y().asConstant()), graph());
-        } else if (y().isConstant()) {
-            Constant c = y().asConstant();
-            if ((c.getKind() == Kind.Float && c.asFloat() == 0.0f) || (c.getKind() == Kind.Double && c.asDouble() == 0.0)) {
-                return x();
-            }
         }
+        // Constant 0.0 can't be eliminated since it can affect the sign of the result.
         return this;
     }
 

--- a/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/calc/FloatSubNode.java	Mon Jun 23 18:30:49 2014 +0200
+++ b/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/calc/FloatSubNode.java	Mon Jun 23 14:38:42 2014 -0700
@@ -55,23 +55,8 @@
         }
         if (x().isConstant() && y().isConstant()) {
             return ConstantNode.forPrimitive(evalConst(x().asConstant(), y().asConstant()), graph());
-        } else if (y().isConstant()) {
-            Constant c = y().asConstant();
-            if (c.getKind() == Kind.Float) {
-                float f = c.asFloat();
-                if (f == 0.0f) {
-                    return x();
-                }
-                return graph().unique(new FloatAddNode(stamp(), x(), ConstantNode.forFloat(-f, graph()), isStrictFP()));
-            } else {
-                assert c.getKind() == Kind.Double;
-                double d = c.asDouble();
-                if (d == 0.0) {
-                    return x();
-                }
-                return graph().unique(new FloatAddNode(stamp(), x(), ConstantNode.forDouble(-d, graph()), isStrictFP()));
-            }
         }
+        // Constant 0.0 can't be eliminated since it can affect the sign of the result.
         return this;
     }