--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.graal.truffle.test/sl/TestIsCompilationConstant1.sl	Tue Oct 14 20:02:44 2014 +0200
@@ -0,0 +1,40 @@
+
+
+function testConstantValue1() {
+    return isCompilationConstant(42);
+}
+
+function testConstantValue2() {
+    return isCompilationConstant(21 + 21);
+}
+
+function testConstantSequence() {
+    40;
+    return isCompilationConstant(42);
+}
+
+function testConstantLocalVariable() {
+    x = 42;
+    return isCompilationConstant(x);
+}
+
+function testNonConstantAdd() {
+    return isCompilationConstant(42 + "42");
+}
+
+
+function main() {
+    callFunctionsWith("testConstant", harnessTrue);
+    callFunctionsWith("testNonConstant", harnessFalse);
+}  
+
+function harnessTrue(testFunction) {
+    callUntilOptimized(testFunction);
+    assertTrue(testFunction(), "test function " + testFunction + " is not constant");
+}
+
+
+function harnessFalse(testFunction) {
+    callUntilOptimized(testFunction);
+    assertFalse(testFunction(), "test function " + testFunction + " is constant");
+}
\ No newline at end of file

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.graal.truffle.test/src/com/oracle/graal/truffle/test/builtins/SLIsCompilationConstantBuiltin.java	Tue Oct 14 20:02:44 2014 +0200
@@ -0,0 +1,43 @@
+/*
+ * 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.truffle.test.builtins;
+
+import com.oracle.truffle.api.*;
+import com.oracle.truffle.api.dsl.*;
+import com.oracle.truffle.api.nodes.*;
+
+/**
+ * Checks whether or not a function is optimized by the Graal runtime.
+ */
+@NodeInfo(shortName = "isCompilationConstant")
+public abstract class SLIsCompilationConstantBuiltin extends SLGraalRuntimeBuiltin {
+
+    @Specialization
+    public boolean isCompilationConstant(Object value) {
+        if (CompilerDirectives.inCompiledCode()) {
+            return CompilerDirectives.isCompilationConstant(value);
+        } else {
+            return true;
+        }
+    }
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.graal.truffle/src/com/oracle/graal/truffle/nodes/IsCompilationConstantNode.java	Tue Oct 14 20:02:44 2014 +0200
@@ -0,0 +1,62 @@
+/*
+ * 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.truffle.nodes;
+
+import com.oracle.graal.graph.*;
+import com.oracle.graal.graph.spi.*;
+import com.oracle.graal.nodeinfo.*;
+import com.oracle.graal.nodes.*;
+import com.oracle.graal.nodes.extended.*;
+import com.oracle.graal.nodes.spi.*;
+import com.oracle.graal.replacements.nodes.*;
+
+@NodeInfo
+public class IsCompilationConstantNode extends MacroStateSplitNode implements Canonicalizable {
+
+    public static IsCompilationConstantNode create(Invoke invoke) {
+        return USE_GENERATED_NODES ? new IsCompilationConstantNodeGen(invoke) : new IsCompilationConstantNode(invoke);
+    }
+
+    protected IsCompilationConstantNode(Invoke invoke) {
+        super(invoke);
+        assert arguments.size() == 1;
+    }
+
+    @Override
+    public void lower(LoweringTool tool) {
+        /* Invoke will return false. */
+        replaceWithInvoke().lower(tool);
+    }
+
+    @Override
+    public Node canonical(CanonicalizerTool tool) {
+        ValueNode arg0 = arguments.get(0);
+        if (arg0 instanceof BoxNode) {
+            arg0 = ((BoxNode) arg0).getValue();
+        }
+        if (arg0.isConstant()) {
+            return ConstantNode.forBoolean(true);
+        }
+        return this;
+    }
+}

--- a/graal/com.oracle.graal.truffle/src/com/oracle/graal/truffle/substitutions/CompilerDirectivesSubstitutions.java	Tue Oct 14 20:02:44 2014 +0200
+++ b/graal/com.oracle.graal.truffle/src/com/oracle/graal/truffle/substitutions/CompilerDirectivesSubstitutions.java	Tue Oct 14 20:02:44 2014 +0200
@@ -84,6 +84,9 @@
         return FrameWithoutBoxing.class;
     }
 
+    @MacroSubstitution(macro = IsCompilationConstantNode.class, isStatic = true)
+    public static native boolean isCompilationConstant(Object value);
+
     @MacroSubstitution(macro = CustomizedUnsafeLoadMacroNode.class, isStatic = true)
     public static native boolean unsafeGetBoolean(Object receiver, long offset, boolean condition, Object locationIdentity);
 

--- a/graal/com.oracle.truffle.api/src/com/oracle/truffle/api/CompilerDirectives.java	Tue Oct 14 20:02:44 2014 +0200
+++ b/graal/com.oracle.truffle.api/src/com/oracle/truffle/api/CompilerDirectives.java	Tue Oct 14 20:02:44 2014 +0200
@@ -99,6 +99,32 @@
     }
 
     /**
+     * Returns a boolean indicating whether or not a given value is seen as constant in optimized
+     * code. If this method is called in the interpreter this method will always return
+     * <code>false</code>. This API may be used in combination with {@link #inCompiledCode()} to
+     * implement compilation constant assertions in the following way:
+     *
+     * <pre>
+     * <code>
+     * void assertCompilationConstant(Object value) {
+     *   if (inCompiledCode()) {
+     *     if (!isCompilationConstant(value)) {
+     *       throw new AssertionError("Given value is not constant");
+     *     }
+     *   }
+     * }
+     * </code>
+     * </pre>
+     *
+     * @param value
+     * @return {@code true} when given value is seen as compilation constant, {@code false} if not
+     *         compilation constant.
+     */
+    public static boolean isCompilationConstant(Object value) {
+        return false;
+    }
+
+    /**
      * Directive for the compiler that the given runnable should only be executed in the interpreter
      * and ignored in the compiled code.
      *