--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/alloc/AllocationStageVerifier.java	Wed Nov 11 11:06:55 2015 +0100
@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2015, 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.lir.alloc;
+
+import static com.oracle.graal.lir.LIRValueUtil.isVariable;
+import static com.oracle.graal.lir.LIRValueUtil.isVirtualStackSlot;
+
+import java.util.EnumSet;
+import java.util.List;
+
+import jdk.vm.ci.code.TargetDescription;
+import jdk.vm.ci.meta.Value;
+
+import com.oracle.graal.compiler.common.alloc.RegisterAllocationConfig;
+import com.oracle.graal.compiler.common.cfg.AbstractBlockBase;
+import com.oracle.graal.lir.LIR;
+import com.oracle.graal.lir.LIRInstruction;
+import com.oracle.graal.lir.LIRInstruction.OperandFlag;
+import com.oracle.graal.lir.LIRInstruction.OperandMode;
+import com.oracle.graal.lir.gen.LIRGenerationResult;
+import com.oracle.graal.lir.gen.LIRGeneratorTool.MoveFactory;
+import com.oracle.graal.lir.phases.AllocationPhase;
+
+/**
+ * Verifies that all virtual operands have been replaced by concrete values.
+ */
+public class AllocationStageVerifier extends AllocationPhase {
+
+    @Override
+    protected <B extends AbstractBlockBase<B>> void run(TargetDescription target, LIRGenerationResult lirGenRes, List<B> codeEmittingOrder, List<B> linearScanOrder, MoveFactory spillMoveFactory,
+                    RegisterAllocationConfig registerAllocationConfig) {
+        verifyLIR(lirGenRes.getLIR());
+
+    }
+
+    protected void verifyLIR(LIR lir) {
+        for (AbstractBlockBase<?> block : (List<? extends AbstractBlockBase<?>>) lir.getControlFlowGraph().getBlocks()) {
+            verifyBlock(lir, block);
+        }
+    }
+
+    protected void verifyBlock(LIR lir, AbstractBlockBase<?> block) {
+        for (LIRInstruction inst : lir.getLIRforBlock(block)) {
+            verifyInstruction(inst);
+        }
+    }
+
+    protected void verifyInstruction(LIRInstruction inst) {
+        inst.visitEachInput(this::verifyOperands);
+        inst.visitEachOutput(this::verifyOperands);
+        inst.visitEachAlive(this::verifyOperands);
+        inst.visitEachTemp(this::verifyOperands);
+    }
+
+    /**
+     * @param instruction
+     * @param value
+     * @param mode
+     * @param flags
+     */
+    protected void verifyOperands(LIRInstruction instruction, Value value, OperandMode mode, EnumSet<OperandFlag> flags) {
+        assert !isVirtualStackSlot(value) && !isVariable(value) : "Virtual values not allowed after allocation stage: " + value;
+    }
+
+}

--- a/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/phases/AllocationStage.java	Wed Nov 11 17:14:06 2015 +0100
+++ b/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/phases/AllocationStage.java	Wed Nov 11 11:06:55 2015 +0100
@@ -24,6 +24,8 @@
 
 import static com.oracle.graal.compiler.common.BackendOptions.UserOptions.TraceRA;
 
+import com.oracle.graal.compiler.common.GraalOptions;
+import com.oracle.graal.lir.alloc.AllocationStageVerifier;
 import com.oracle.graal.lir.alloc.lsra.LinearScanPhase;
 import com.oracle.graal.lir.alloc.trace.TraceRegisterAllocationPhase;
 import com.oracle.graal.lir.dfa.LocationMarkerPhase;
@@ -49,5 +51,9 @@
         }
         // currently we mark locations only if we do register allocation
         appendPhase(new LocationMarkerPhase());
+
+        if (GraalOptions.DetailedAsserts.getValue()) {
+            appendPhase(new AllocationStageVerifier());
+        }
     }
 }