--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.max.asmdis/src/com/sun/max/asm/gen/cisc/x86/X86InstructionDescriptionVisitor.java	Sat Dec 17 19:59:18 2011 +0100
@@ -0,0 +1,146 @@
+/*
+ * Copyright (c) 2007, 2011, 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.sun.max.asm.gen.cisc.x86;
+
+import com.sun.max.asm.gen.*;
+import com.sun.max.asm.gen.cisc.*;
+import com.sun.max.asm.x86.*;
+import com.sun.max.program.*;
+
+/**
+ * Almost like the visitor pattern.
+ * Specialized dispatch over InstructionDescription objects.
+ */
+public interface X86InstructionDescriptionVisitor {
+
+    void visitOperandCode(OperandCode operandCode, X86Operand.Designation designation, ArgumentRange argumentRange, TestArgumentExclusion testArgumentExclusion) throws TemplateNotNeededException;
+
+    void visitAddressingMethodCode(AddressingMethodCode addressingMethodCode, X86Operand.Designation designation) throws TemplateNotNeededException;
+
+    void visitOperandTypeCode(OperandTypeCode operandTypeCode) throws TemplateNotNeededException;
+
+    void visitRegisterOperandCode(RegisterOperandCode registerOperandCode, X86Operand.Designation designation, ImplicitOperand.ExternalPresence externalPresence);
+
+    void visitGeneralRegister(GeneralRegister generalRegister, X86Operand.Designation designation, ImplicitOperand.ExternalPresence externalPresence);
+
+    void visitSegmentRegister(SegmentRegister segmentRegister, X86Operand.Designation designation);
+
+    void visitModRMGroup(ModRMGroup modRMGroup) throws TemplateNotNeededException;
+
+    void visitModCase(X86TemplateContext.ModCase modCase) throws TemplateNotNeededException;
+
+    void visitFloatingPointOperandCode(FloatingPointOperandCode floatingPointOperandCode, X86Operand.Designation designation, TestArgumentExclusion testArgumentExclusion) throws TemplateNotNeededException;
+
+    void visitFPStackRegister(FPStackRegister fpStackRegister, X86Operand.Designation designation);
+
+    void visitString(String string);
+
+    void visitInteger(Integer integer, X86Operand.Designation designation);
+
+    void visitHexByte(HexByte hexByte) throws TemplateNotNeededException;
+
+    void visitInstructionConstraint(InstructionConstraint constraint);
+
+    public static final class Static {
+        private Static() {
+        }
+
+        /**
+         * @return whether the specification constitutes an operand
+         * @throws TemplateNotNeededException
+         */
+        private static boolean visitSpecification(X86InstructionDescriptionVisitor visitor, Object specification,
+                                                  final X86Operand.Designation designation, ArgumentRange argumentRange,
+                                                  final TestArgumentExclusion testArgumentExclusion, ImplicitOperand.ExternalPresence externalPresence) throws TemplateNotNeededException {
+            if (specification instanceof OperandCode) {
+                visitor.visitOperandCode((OperandCode) specification, designation, argumentRange, testArgumentExclusion);
+                return true;
+            } else if (specification instanceof AddressingMethodCode) {
+                visitor.visitAddressingMethodCode((AddressingMethodCode) specification, designation);
+                return true;
+            } else if (specification instanceof OperandTypeCode) {
+                visitor.visitOperandTypeCode((OperandTypeCode) specification);
+                return false;
+            } else if (specification instanceof RegisterOperandCode) {
+                visitor.visitRegisterOperandCode((RegisterOperandCode) specification, designation, externalPresence);
+                return true;
+            } else if (specification instanceof GeneralRegister) {
+                visitor.visitGeneralRegister((GeneralRegister) specification, designation, externalPresence);
+                return true;
+            } else if (specification instanceof SegmentRegister) {
+                visitor.visitSegmentRegister((SegmentRegister) specification, designation);
+                return true;
+            } else if (specification instanceof ModRMGroup) {
+                visitor.visitModRMGroup((ModRMGroup) specification);
+                return false;
+            } else if (specification instanceof X86TemplateContext.ModCase) {
+                visitor.visitModCase((X86TemplateContext.ModCase) specification);
+                return false;
+            } else if (specification instanceof FloatingPointOperandCode) {
+                visitor.visitFloatingPointOperandCode((FloatingPointOperandCode) specification, designation, testArgumentExclusion);
+                return true;
+            } else if (specification instanceof FPStackRegister) {
+                visitor.visitFPStackRegister((FPStackRegister) specification, designation);
+                return true;
+            } else if (specification instanceof String) {
+                visitor.visitString((String) specification);
+                return false;
+            } else if (specification instanceof Integer) {
+                visitor.visitInteger((Integer) specification, designation);
+                return true;
+            } else if (specification instanceof ArgumentRange) {
+                final ArgumentRange newArgumentRange = (ArgumentRange) specification;
+                return visitSpecification(visitor, newArgumentRange.wrappedSpecification(), designation, newArgumentRange, testArgumentExclusion, externalPresence);
+            } else if (specification instanceof HexByte) {
+                visitor.visitHexByte((HexByte) specification);
+                return false;
+            } else if (specification instanceof TestArgumentExclusion) {
+                final TestArgumentExclusion exclusion = (TestArgumentExclusion) specification;
+                return visitSpecification(visitor, exclusion.wrappedSpecification(), designation, argumentRange, exclusion, externalPresence);
+            } else if (specification instanceof ExternalOmission) {
+                final ExternalOmission omission = (ExternalOmission) specification;
+                return visitSpecification(visitor, omission.wrappedSpecification(), designation, argumentRange, testArgumentExclusion, ImplicitOperand.ExternalPresence.OMITTED);
+            } else {
+                throw ProgramError.unexpected("unknown instruction description specification: " + specification);
+            }
+        }
+
+        /**
+         * @return whether this instruction description is to be used to create a template in the given context
+         */
+        public static boolean visitInstructionDescription(X86InstructionDescriptionVisitor visitor, InstructionDescription instructionDescription) {
+            try {
+                int designationIndex = 0;
+                for (Object specification : instructionDescription) {
+                    final X86Operand.Designation designation = X86Operand.Designation.VALUES.get(designationIndex);
+                    if (visitSpecification(visitor, specification, designation, ArgumentRange.UNSPECIFIED, TestArgumentExclusion.NONE, ImplicitOperand.ExternalPresence.EXPLICIT)) {
+                        designationIndex++;
+                    }
+                }
+                return true;
+            } catch (TemplateNotNeededException templateNotNeededException) {
+                return false;
+            }
+        }
+    }
+}