Merge some useful changes from MD
[mono.git] / mcs / mcs / codegen.cs
index 468b6ef8eae327d12e94855e5db076b72816c6c9..530eb91e3b93b2d126f36a3638d1590c8662483c 100644 (file)
 //
 // codegen.cs: The code generator
 //
-// Author:
+// Authors:
 //   Miguel de Icaza (miguel@ximian.com)
+//   Marek Safar (marek.safar@gmail.com)
 //
 // Copyright 2001, 2002, 2003 Ximian, Inc.
 // Copyright 2004 Novell, Inc.
 //
 
-//
-// Please leave this defined on SVN: The idea is that when we ship the
-// compiler to end users, if the compiler crashes, they have a chance
-// to narrow down the problem.   
-//
-// Only remove it if you need to debug locally on your tree.
-//
-#define PRODUCTION
-
 using System;
-using System.IO;
-using System.Collections;
-using System.Collections.Specialized;
-using System.Globalization;
-using System.Reflection;
-using System.Reflection.Emit;
-using System.Runtime.InteropServices;
-using System.Security;
-using System.Security.Cryptography;
-using System.Security.Permissions;
-
-using Mono.Security.Cryptography;
-
-namespace Mono.CSharp {
-
-       /// <summary>
-       ///    Code generator class.
-       /// </summary>
-       public class CodeGen {
-               static AppDomain current_domain;
-
-               public static AssemblyClass Assembly;
-
-               static CodeGen ()
-               {
-                       Reset ();
-               }
-
-               public static void Reset ()
-               {
-                       Assembly = new AssemblyClass ();
-               }
-
-               public static string Basename (string name)
-               {
-                       int pos = name.LastIndexOf ('/');
-
-                       if (pos != -1)
-                               return name.Substring (pos + 1);
-
-                       pos = name.LastIndexOf ('\\');
-                       if (pos != -1)
-                               return name.Substring (pos + 1);
-
-                       return name;
-               }
-
-               public static string Dirname (string name)
-               {
-                       int pos = name.LastIndexOf ('/');
-
-                       if (pos != -1)
-                               return name.Substring (0, pos);
-
-                       pos = name.LastIndexOf ('\\');
-                       if (pos != -1)
-                               return name.Substring (0, pos);
-
-                       return ".";
-               }
-
-               static public string FileName;
+using System.Collections.Generic;
 
-#if MS_COMPATIBLE
-               const AssemblyBuilderAccess COMPILER_ACCESS = 0;
+#if STATIC
+using MetaType = IKVM.Reflection.Type;
+using IKVM.Reflection;
+using IKVM.Reflection.Emit;
 #else
-               /* Keep this in sync with System.Reflection.Emit.AssemblyBuilder */
-               const AssemblyBuilderAccess COMPILER_ACCESS = (AssemblyBuilderAccess) 0x800;
-#endif
-                               
-               //
-               // Initializes the code generator variables for interactive use (repl)
-               //
-               static public void InitDynamic (string name)
-               {
-                       current_domain = AppDomain.CurrentDomain;
-                       AssemblyName an = Assembly.GetAssemblyName (name, name);
-                       
-                       Assembly.Builder = current_domain.DefineDynamicAssembly (an, AssemblyBuilderAccess.Run | COMPILER_ACCESS);
-                       RootContext.ToplevelTypes = new ModuleContainer (true);
-                       RootContext.ToplevelTypes.Builder = Assembly.Builder.DefineDynamicModule (Basename (name), false);
-#if GMCS_SOURCE
-                       Assembly.Name = Assembly.Builder.GetName ();
-#endif
-               }
-               
-               //
-               // Initializes the code generator variables
-               //
-               static public bool Init (string name, string output, bool want_debugging_support)
-               {
-                       FileName = output;
-                       AssemblyName an = Assembly.GetAssemblyName (name, output);
-                       if (an == null)
-                               return false;
-
-                       if (an.KeyPair != null) {
-                               // If we are going to strong name our assembly make
-                               // sure all its refs are strong named
-                               foreach (Assembly a in GlobalRootNamespace.Instance.Assemblies) {
-                                       AssemblyName ref_name = a.GetName ();
-                                       byte [] b = ref_name.GetPublicKeyToken ();
-                                       if (b == null || b.Length == 0) {
-                                               Report.Error (1577, "Assembly generation failed " +
-                                                               "-- Referenced assembly '" +
-                                                               ref_name.Name +
-                                                               "' does not have a strong name.");
-                                               //Environment.Exit (1);
-                                       }
-                               }
-                       }
-                       
-                       current_domain = AppDomain.CurrentDomain;
-
-                       try {
-                               Assembly.Builder = current_domain.DefineDynamicAssembly (an,
-                                       AssemblyBuilderAccess.RunAndSave | COMPILER_ACCESS, Dirname (name));
-                       }
-                       catch (ArgumentException) {
-                               // specified key may not be exportable outside it's container
-                               if (RootContext.StrongNameKeyContainer != null) {
-                                       Report.Error (1548, "Could not access the key inside the container `" +
-                                               RootContext.StrongNameKeyContainer + "'.");
-                                       Environment.Exit (1);
-                               }
-                               throw;
-                       }
-                       catch (CryptographicException) {
-                               if ((RootContext.StrongNameKeyContainer != null) || (RootContext.StrongNameKeyFile != null)) {
-                                       Report.Error (1548, "Could not use the specified key to strongname the assembly.");
-                                       Environment.Exit (1);
-                               }
-                               return false;
-                       }
-
-#if GMCS_SOURCE
-                       // Get the complete AssemblyName from the builder
-                       // (We need to get the public key and token)
-                       Assembly.Name = Assembly.Builder.GetName ();
-#endif
-
-                       //
-                       // Pass a path-less name to DefineDynamicModule.  Wonder how
-                       // this copes with output in different directories then.
-                       // FIXME: figure out how this copes with --output /tmp/blah
-                       //
-                       // If the third argument is true, the ModuleBuilder will dynamically
-                       // load the default symbol writer.
-                       //
-                       try {
-                               RootContext.ToplevelTypes.Builder = Assembly.Builder.DefineDynamicModule (
-                                       Basename (name), Basename (output), want_debugging_support);
-
-#if !MS_COMPATIBLE
-                               // TODO: We should use SymbolWriter from DefineDynamicModule
-                               if (want_debugging_support && !SymbolWriter.Initialize (RootContext.ToplevelTypes.Builder, output)) {
-                                       Report.Error (40, "Unexpected debug information initialization error `{0}'",
-                                               "Could not find the symbol writer assembly (Mono.CompilerServices.SymbolWriter.dll)");
-                                       return false;
-                               }
+using MetaType = System.Type;
+using System.Reflection;
+using System.Reflection.Emit;
 #endif
-                       } catch (ExecutionEngineException e) {
-                               Report.Error (40, "Unexpected debug information initialization error `{0}'",
-                                       e.Message);
-                               return false;
-                       }
-
-                       return true;
-               }
-
-               static public void Save (string name, bool saveDebugInfo)
-               {
-                       try {
-                               Assembly.Builder.Save (Basename (name));
-                       }
-                       catch (COMException) {
-                               if ((RootContext.StrongNameKeyFile == null) || (!RootContext.StrongNameDelaySign))
-                                       throw;
-
-                               // FIXME: it seems Microsoft AssemblyBuilder doesn't like to delay sign assemblies 
-                               Report.Error (1548, "Couldn't delay-sign the assembly with the '" +
-                                       RootContext.StrongNameKeyFile +
-                                       "', Use MCS with the Mono runtime or CSC to compile this assembly.");
-                       }
-                       catch (System.IO.IOException io) {
-                               Report.Error (16, "Could not write to file `"+name+"', cause: " + io.Message);
-                               return;
-                       }
-                       catch (System.UnauthorizedAccessException ua) {
-                               Report.Error (16, "Could not write to file `"+name+"', cause: " + ua.Message);
-                               return;
-                       }
-
-                       //
-                       // Write debuger symbol file
-                       //
-                       if (saveDebugInfo)
-                               SymbolWriter.WriteSymbolFile ();
-                       }
-       }
-
-
-       /// <summary>
-       /// An interface to hold all the information needed in the resolving phase.
-       /// </summary>
-       public interface IResolveContext
-       {
-               DeclSpace DeclContainer { get; }
-               bool IsInObsoleteScope { get; }
-               bool IsInUnsafeScope { get; }
-
-               // the declcontainer to lookup for type-parameters.  Should only use LookupGeneric on it.
-               //
-               // FIXME: This is somewhat of a hack.  We don't need a full DeclSpace for this.  We just need the
-               //        current type parameters in scope. IUIC, that will require us to rewrite GenericMethod.
-               //        Maybe we can replace this with a 'LookupGeneric (string)' instead, but we'll have to 
-               //        handle generic method overrides differently
-               DeclSpace GenericDeclContainer { get; }
-       }
 
+namespace Mono.CSharp
+{
        /// <summary>
        ///   An Emit Context is created for each body of code (from methods,
        ///   properties bodies, indexer bodies or constructor bodies)
        /// </summary>
-       public class EmitContext : IResolveContext {
-
-               //
-               // Holds a varible used during collection or object initialization.
-               //
-               public Expression CurrentInitializerVariable;
-
-               DeclSpace decl_space;
-               
-               public DeclSpace TypeContainer;
-               public ILGenerator ig;
-
-               [Flags]
-               public enum Flags : int {
-                       /// <summary>
-                       ///   This flag tracks the `checked' state of the compilation,
-                       ///   it controls whether we should generate code that does overflow
-                       ///   checking, or if we generate code that ignores overflows.
-                       ///
-                       ///   The default setting comes from the command line option to generate
-                       ///   checked or unchecked code plus any source code changes using the
-                       ///   checked/unchecked statements or expressions.   Contrast this with
-                       ///   the ConstantCheckState flag.
-                       /// </summary>
-                       CheckState = 1 << 0,
-
-                       /// <summary>
-                       ///   The constant check state is always set to `true' and cant be changed
-                       ///   from the command line.  The source code can change this setting with
-                       ///   the `checked' and `unchecked' statements and expressions. 
-                       /// </summary>
-                       ConstantCheckState = 1 << 1,
-
-                       AllCheckStateFlags = CheckState | ConstantCheckState,
-
-                       /// <summary>
-                       ///  Whether we are inside an unsafe block
-                       /// </summary>
-                       InUnsafe = 1 << 2,
-
-                       InCatch = 1 << 3,
-                       InFinally = 1 << 4,
-
-                       /// <summary>
-                       ///   Whether control flow analysis is enabled
-                       /// </summary>
-                       DoFlowAnalysis = 1 << 5,
-
-                       /// <summary>
-                       ///   Whether control flow analysis is disabled on structs
-                       ///   (only meaningful when DoFlowAnalysis is set)
-                       /// </summary>
-                       OmitStructFlowAnalysis = 1 << 6,
-
-                       ///
-                       /// Indicates the current context is in probing mode, no errors are reported. 
-                       ///
-                       ProbingMode = 1 <<      7,
-
-                       //
-                       // Inside field intializer expression
-                       //
-                       InFieldInitializer = 1 << 8,
-                       
-                       InferReturnType = 1 << 9,
-                       
-                       InCompoundAssignment = 1 << 10,
-
-                       OmitDebuggingInfo = 1 << 11
-               }
-
-               Flags flags;
-
-               /// <summary>
-               ///   Whether we are emitting code inside a static or instance method
-               /// </summary>
-               public bool IsStatic;
-
-               /// <summary>
-               ///   Whether the actual created method is static or instance method.
-               ///   Althoug the method might be declared as `static', if an anonymous
-               ///   method is involved, we might turn this into an instance method.
-               ///
-               ///   So this reflects the low-level staticness of the method, while
-               ///   IsStatic represents the semantic, high-level staticness.
-               /// </summary>
-               //public bool MethodIsStatic;
+       public class EmitContext : BuilderContext
+       {
+               // TODO: Has to be private
+               public readonly ILGenerator ig;
 
                /// <summary>
                ///   The value that is allowed to be returned or NULL if there is no
                ///   return type.
                /// </summary>
-               Type return_type;
-
-               /// <summary>
-               ///   Points to the Type (extracted from the TypeContainer) that
-               ///   declares this body of code
-               /// </summary>
-               public readonly Type ContainerType;
-               
-               /// <summary>
-               ///   Whether this is generating code for a constructor
-               /// </summary>
-               public bool IsConstructor;
+               readonly TypeSpec return_type;
 
                /// <summary>
                ///   Keeps track of the Type to LocalBuilder temporary storage created
                ///   to store structures (used to compute the address of the structure
                ///   value on structure method invocations)
                /// </summary>
-               public Hashtable temporary_storage;
-
-               public Block CurrentBlock;
-
-               public int CurrentFile;
+               Dictionary<TypeSpec, object> temporary_storage;
 
                /// <summary>
                ///   The location where we store the return value.
                /// </summary>
-               LocalBuilder return_value;
+               public LocalBuilder return_value;
 
                /// <summary>
                ///   The location where return has to jump to return the
@@ -375,547 +63,536 @@ namespace Mono.CSharp {
                public bool HasReturnLabel;
 
                /// <summary>
-               ///  Whether we are in a `fixed' initialization
-               /// </summary>
-               public bool InFixedInitializer;
-
-               /// <summary>
-               ///  Whether we are inside an anonymous method.
-               /// </summary>
-               public AnonymousExpression CurrentAnonymousMethod;
-               
-               /// <summary>
-               ///   Location for this EmitContext
+               ///   Current loop begin and end labels.
                /// </summary>
-               public Location loc;
+               public Label LoopBegin, LoopEnd;
 
                /// <summary>
-               ///   Inside an enum definition, we do not resolve enumeration values
-               ///   to their enumerations, but rather to the underlying type/value
-               ///   This is so EnumVal + EnumValB can be evaluated.
-               ///
-               ///   There is no "E operator + (E x, E y)", so during an enum evaluation
-               ///   we relax the rules
+               ///   Default target in a switch statement.   Only valid if
+               ///   InSwitch is true
                /// </summary>
-               public bool InEnumContext;
-
-               public readonly IResolveContext ResolveContext;
+               public Label DefaultTarget;
 
                /// <summary>
-               ///    The current iterator
+               ///   If this is non-null, points to the current switch statement
                /// </summary>
-               public Iterator CurrentIterator {
-                       get { return CurrentAnonymousMethod as Iterator; }
-               }
+               public Switch Switch;
 
                /// <summary>
-               ///    Whether we are in the resolving stage or not
+               ///  Whether we are inside an anonymous method.
                /// </summary>
-               enum Phase {
-                       Created,
-                       Resolving,
-                       Emitting
-               }
-
-               bool isAnonymousMethodAllowed = true;
-
-               Phase current_phase;
-               FlowBranching current_flow_branching;
+               public AnonymousExpression CurrentAnonymousMethod;
+               
+               readonly IMemberContext member_context;
 
-               static int next_id = 0;
-               int id = ++next_id;
+               DynamicSiteClass dynamic_site_container;
 
-               public override string ToString ()
-               {
-                       return String.Format ("EmitContext ({0}:{1})", id,
-                                             CurrentAnonymousMethod, loc);
-               }
-               
-               public EmitContext (IResolveContext rc, DeclSpace parent, DeclSpace ds, Location l, ILGenerator ig,
-                                   Type return_type, int code_flags, bool is_constructor)
+               public EmitContext (IMemberContext rc, ILGenerator ig, TypeSpec return_type)
                {
-                       this.ResolveContext = rc;
+                       this.member_context = rc;
                        this.ig = ig;
 
-                       TypeContainer = parent;
-                       this.decl_space = ds;
-                       if (RootContext.Checked)
-                               flags |= Flags.CheckState;
-                       flags |= Flags.ConstantCheckState;
-
-                       if (return_type == null)
-                               throw new ArgumentNullException ("return_type");
-#if GMCS_SOURCE
-                       if ((return_type is TypeBuilder) && return_type.IsGenericTypeDefinition)
-                               throw new InternalErrorException ();
-#endif
+                       this.return_type = return_type;
 
-                       IsStatic = (code_flags & Modifiers.STATIC) != 0;
-                       ReturnType = return_type;
-                       IsConstructor = is_constructor;
-                       CurrentBlock = null;
-                       CurrentFile = 0;
-                       current_phase = Phase.Created;
-
-                       if (parent != null){
-                               // Can only be null for the ResolveType contexts.
-                               ContainerType = parent.TypeBuilder;
-                               if (rc.IsInUnsafeScope)
-                                       flags |= Flags.InUnsafe;
-                       }
-                       loc = l;
+#if STATIC
+                       ig.__CleverExceptionBlockAssistance ();
+#endif
                }
 
-               public EmitContext (IResolveContext rc, DeclSpace ds, Location l, ILGenerator ig,
-                                   Type return_type, int code_flags, bool is_constructor)
-                       : this (rc, ds, ds, l, ig, return_type, code_flags, is_constructor)
-               {
-               }
+               #region Properties
 
-               public EmitContext (IResolveContext rc, DeclSpace ds, Location l, ILGenerator ig,
-                                   Type return_type, int code_flags)
-                       : this (rc, ds, ds, l, ig, return_type, code_flags, false)
-               {
+               public TypeSpec CurrentType {
+                       get { return member_context.CurrentType; }
                }
 
-               // IResolveContext.DeclContainer
-               public DeclSpace DeclContainer { 
-                       get { return decl_space; }
-                       set { decl_space = value; }
+               public TypeParameter[] CurrentTypeParameters {
+                       get { return member_context.CurrentTypeParameters; }
                }
 
-               // IResolveContext.GenericDeclContainer
-               public DeclSpace GenericDeclContainer {
-                       get { return DeclContainer; }
+               public MemberCore CurrentTypeDefinition {
+                       get { return member_context.CurrentMemberDefinition; }
                }
 
-               public bool CheckState {
-                       get { return (flags & Flags.CheckState) != 0; }
+               public bool IsStatic {
+                       get { return member_context.IsStatic; }
                }
 
-               public bool ConstantCheckState {
-                       get { return (flags & Flags.ConstantCheckState) != 0; }
-               }
-
-               public bool InUnsafe {
-                       get { return (flags & Flags.InUnsafe) != 0; }
+               bool IsAnonymousStoreyMutateRequired {
+                       get {
+                               return CurrentAnonymousMethod != null &&
+                                       CurrentAnonymousMethod.Storey != null &&
+                                       CurrentAnonymousMethod.Storey.Mutator != null;
+                       }
                }
 
-               public bool InCatch {
-                       get { return (flags & Flags.InCatch) != 0; }
+               public IMemberContext MemberContext {
+                       get {
+                               return member_context;
+                       }
                }
 
-               public bool InFinally {
-                       get { return (flags & Flags.InFinally) != 0; }
+               public ModuleContainer Module {
+                       get {
+                               return member_context.Module;
+                       }
                }
 
-               public bool DoFlowAnalysis {
-                       get { return (flags & Flags.DoFlowAnalysis) != 0; }
+               // Has to be used for specific emitter errors only any
+               // possible resolver errors have to be reported during Resolve
+               public Report Report {
+                       get {
+                               return member_context.Module.Compiler.Report;
+                       }
                }
 
-               public bool OmitStructFlowAnalysis {
-                       get { return (flags & Flags.OmitStructFlowAnalysis) != 0; }
+               public TypeSpec ReturnType {
+                       get {
+                               return return_type;
+                       }
                }
+               #endregion
 
-               // utility helper for CheckExpr, UnCheckExpr, Checked and Unchecked statements
-               // it's public so that we can use a struct at the callsite
-               public struct FlagsHandle : IDisposable
+               /// <summary>
+               ///   This is called immediately before emitting an IL opcode to tell the symbol
+               ///   writer to which source line this opcode belongs.
+               /// </summary>
+               public void Mark (Location loc)
                {
-                       EmitContext ec;
-                       readonly Flags invmask, oldval;
-
-                       public FlagsHandle (EmitContext ec, Flags flagsToSet)
-                               : this (ec, flagsToSet, flagsToSet)
-                       {
-                       }
+                       if (!SymbolWriter.HasSymbolWriter || HasSet (Options.OmitDebugInfo) || loc.IsNull)
+                               return;
 
-                       internal FlagsHandle (EmitContext ec, Flags mask, Flags val)
-                       {
-                               this.ec = ec;
-                               invmask = ~mask;
-                               oldval = ec.flags & mask;
-                               ec.flags = (ec.flags & invmask) | (val & mask);
+                       SymbolWriter.MarkSequencePoint (ig, loc);
+               }
 
-                               if ((mask & Flags.ProbingMode) != 0)
-                                       Report.DisableReporting ();
-                       }
+               public void DefineLocalVariable (string name, LocalBuilder builder)
+               {
+                       SymbolWriter.DefineLocalVariable (name, builder);
+               }
 
-                       public void Dispose ()
-                       {
-                               if ((invmask & Flags.ProbingMode) == 0)
-                                       Report.EnableReporting ();
+               public void BeginCatchBlock (TypeSpec type)
+               {
+                       ig.BeginCatchBlock (type.GetMetaInfo ());
+               }
 
-                               ec.flags = (ec.flags & invmask) | oldval;
-                       }
+               public void BeginExceptionBlock ()
+               {
+                       ig.BeginExceptionBlock ();
                }
 
-               // Temporarily set all the given flags to the given value.  Should be used in an 'using' statement
-               public FlagsHandle Set (Flags flagsToSet)
+               public void BeginFinallyBlock ()
                {
-                       return new FlagsHandle (this, flagsToSet);
+                       ig.BeginFinallyBlock ();
                }
 
-               public FlagsHandle With (Flags bits, bool enable)
+               public void BeginScope ()
                {
-                       return new FlagsHandle (this, bits, enable ? bits : 0);
+                       SymbolWriter.OpenScope(ig);
                }
 
-               public FlagsHandle WithFlowAnalysis (bool do_flow_analysis, bool omit_struct_analysis)
+               public void EndExceptionBlock ()
                {
-                       Flags newflags = 
-                               (do_flow_analysis ? Flags.DoFlowAnalysis : 0) |
-                               (omit_struct_analysis ? Flags.OmitStructFlowAnalysis : 0);
-                       return new FlagsHandle (this, Flags.DoFlowAnalysis | Flags.OmitStructFlowAnalysis, newflags);
+                       ig.EndExceptionBlock ();
                }
-               
-               /// <summary>
-               ///   If this is true, then Return and ContextualReturn statements
-               ///   will set the ReturnType value based on the expression types
-               ///   of each return statement instead of the method return type
-               ///   (which is initially null).
-               /// </summary>
-               public bool InferReturnType {
-                       get { return (flags & Flags.InferReturnType) != 0; }
+
+               public void EndScope ()
+               {
+                       SymbolWriter.CloseScope(ig);
                }
 
-               // IResolveContext.IsInObsoleteScope
-               public bool IsInObsoleteScope {
-                       get {
-                               // Disables obsolete checks when probing is on
-                               return IsInProbingMode || ResolveContext.IsInObsoleteScope;
+               //
+               // Creates a nested container in this context for all dynamic compiler generated stuff
+               //
+               public DynamicSiteClass CreateDynamicSite ()
+               {
+                       if (dynamic_site_container == null) {
+                               var mc = member_context.CurrentMemberDefinition as MemberBase;
+                               dynamic_site_container = new DynamicSiteClass (CurrentTypeDefinition.Parent.PartialContainer, mc, CurrentTypeParameters);
+
+                               CurrentTypeDefinition.Module.AddCompilerGeneratedClass (dynamic_site_container);
+                               dynamic_site_container.CreateType ();
+                               dynamic_site_container.DefineType ();
+                               dynamic_site_container.ResolveTypeParameters ();
+                               dynamic_site_container.Define ();
                        }
-               }
 
-               public bool IsInProbingMode {
-                       get { return (flags & Flags.ProbingMode) != 0; }
+                       return dynamic_site_container;
                }
 
-               // IResolveContext.IsInUnsafeScope
-               public bool IsInUnsafeScope {
-                       get { return InUnsafe || ResolveContext.IsInUnsafeScope; }
-               }
+               public LocalBuilder DeclareLocal (TypeSpec type, bool pinned)
+               {
+                       if (IsAnonymousStoreyMutateRequired)
+                               type = CurrentAnonymousMethod.Storey.Mutator.Mutate (type);
 
-               public bool IsAnonymousMethodAllowed {
-                       get { return isAnonymousMethodAllowed; }
-                       set { isAnonymousMethodAllowed = value; }
+                       return ig.DeclareLocal (type.GetMetaInfo (), pinned);
                }
 
-               public bool IsInFieldInitializer {
-                       get { return (flags & Flags.InFieldInitializer) != 0; }
+               public Label DefineLabel ()
+               {
+                       return ig.DefineLabel ();
                }
-               
-               public bool IsInCompoundAssignment {
-                       get { return (flags & Flags.InCompoundAssignment) != 0; }
+
+               public void MarkLabel (Label label)
+               {
+                       ig.MarkLabel (label);
                }
 
-               public bool IsVariableCapturingRequired {
-                       get {
-                               return !IsInProbingMode && (CurrentBranching == null || !CurrentBranching.CurrentUsageVector.IsUnreachable);
-                       }
+               public void Emit (OpCode opcode)
+               {
+                       ig.Emit (opcode);
                }
 
-               public FlowBranching CurrentBranching {
-                       get { return current_flow_branching; }
+               public void Emit (OpCode opcode, LocalBuilder local)
+               {
+                       ig.Emit (opcode, local);
                }
 
-               public bool OmitDebuggingInfo {
-                       get { return (flags & Flags.OmitDebuggingInfo) != 0; }
-                       set {
-                               if (value)
-                                       flags |= Flags.OmitDebuggingInfo;
-                               else
-                                       flags &= ~Flags.OmitDebuggingInfo;
-                       }
+               public void Emit (OpCode opcode, string arg)
+               {
+                       ig.Emit (opcode, arg);
                }
 
-               // <summary>
-               //   Starts a new code branching.  This inherits the state of all local
-               //   variables and parameters from the current branching.
-               // </summary>
-               public FlowBranching StartFlowBranching (FlowBranching.BranchingType type, Location loc)
+               public void Emit (OpCode opcode, double arg)
                {
-                       current_flow_branching = FlowBranching.CreateBranching (CurrentBranching, type, null, loc);
-                       return current_flow_branching;
+                       ig.Emit (opcode, arg);
                }
 
-               // <summary>
-               //   Starts a new code branching for block `block'.
-               // </summary>
-               public FlowBranching StartFlowBranching (Block block)
+               public void Emit (OpCode opcode, float arg)
                {
-                       flags |= Flags.DoFlowAnalysis;
+                       ig.Emit (opcode, arg);
+               }
 
-                       current_flow_branching = FlowBranching.CreateBranching (
-                               CurrentBranching, FlowBranching.BranchingType.Block, block, block.StartLocation);
-                       return current_flow_branching;
+               public void Emit (OpCode opcode, int arg)
+               {
+                       ig.Emit (opcode, arg);
                }
 
-               public FlowBranchingTryCatch StartFlowBranching (TryCatch stmt)
+               public void Emit (OpCode opcode, byte arg)
                {
-                       FlowBranchingTryCatch branching = new FlowBranchingTryCatch (CurrentBranching, stmt);
-                       current_flow_branching = branching;
-                       return branching;
+                       ig.Emit (opcode, arg);
                }
 
-               public FlowBranchingException StartFlowBranching (ExceptionStatement stmt)
+               public void Emit (OpCode opcode, Label label)
                {
-                       FlowBranchingException branching = new FlowBranchingException (CurrentBranching, stmt);
-                       current_flow_branching = branching;
-                       return branching;
+                       ig.Emit (opcode, label);
                }
 
-               public FlowBranchingLabeled StartFlowBranching (LabeledStatement stmt)
+               public void Emit (OpCode opcode, Label[] labels)
                {
-                       FlowBranchingLabeled branching = new FlowBranchingLabeled (CurrentBranching, stmt);
-                       current_flow_branching = branching;
-                       return branching;
+                       ig.Emit (opcode, labels);
                }
 
-               public FlowBranchingIterator StartFlowBranching (Iterator iterator)
+               public void Emit (OpCode opcode, TypeSpec type)
                {
-                       FlowBranchingIterator branching = new FlowBranchingIterator (CurrentBranching, iterator);
-                       current_flow_branching = branching;
-                       return branching;
+                       if (IsAnonymousStoreyMutateRequired)
+                               type = CurrentAnonymousMethod.Storey.Mutator.Mutate (type);
+
+                       ig.Emit (opcode, type.GetMetaInfo ());
                }
 
-               public FlowBranchingToplevel StartFlowBranching (ToplevelBlock stmt)
+               public void Emit (OpCode opcode, FieldSpec field)
                {
-                       FlowBranchingToplevel branching = new FlowBranchingToplevel (CurrentBranching, stmt);
-                       current_flow_branching = branching;
-                       return branching;
+                       if (IsAnonymousStoreyMutateRequired)
+                               field = field.Mutate (CurrentAnonymousMethod.Storey.Mutator);
+
+                       ig.Emit (opcode, field.GetMetaInfo ());
                }
 
-               // <summary>
-               //   Ends a code branching.  Merges the state of locals and parameters
-               //   from all the children of the ending branching.
-               // </summary>
-               public bool EndFlowBranching ()
+               public void Emit (OpCode opcode, MethodSpec method)
                {
-                       FlowBranching old = current_flow_branching;
-                       current_flow_branching = current_flow_branching.Parent;
+                       if (IsAnonymousStoreyMutateRequired)
+                               method = method.Mutate (CurrentAnonymousMethod.Storey.Mutator);
 
-                       FlowBranching.UsageVector vector = current_flow_branching.MergeChild (old);
-                       return vector.IsUnreachable;
+                       if (method.IsConstructor)
+                               ig.Emit (opcode, (ConstructorInfo) method.GetMetaInfo ());
+                       else
+                               ig.Emit (opcode, (MethodInfo) method.GetMetaInfo ());
                }
 
-               // <summary>
-               //   Kills the current code branching.  This throws away any changed state
-               //   information and should only be used in case of an error.
-               // </summary>
-               // FIXME: this is evil
-               public void KillFlowBranching ()
+               // TODO: REMOVE breaks mutator
+               public void Emit (OpCode opcode, MethodInfo method)
                {
-                       current_flow_branching = current_flow_branching.Parent;
+                       ig.Emit (opcode, method);
                }
 
-               public bool MustCaptureVariable (LocalInfo local)
+               public void Emit (OpCode opcode, MethodSpec method, MetaType[] vargs)
                {
-                       if (CurrentAnonymousMethod == null)
-                               return false;
+                       // TODO MemberCache: This should mutate too
+                       ig.EmitCall (opcode, (MethodInfo) method.GetMetaInfo (), vargs);
+               }
 
-                       // FIXME: IsIterator is too aggressive, we should capture only if child
-                       // block contains yield
-                       if (CurrentAnonymousMethod.IsIterator)
-                               return true;
+               public void EmitArrayNew (ArrayContainer ac)
+               {
+                       if (ac.Rank == 1) {
+                               Emit (OpCodes.Newarr, ac.Element);
+                       } else {
+                               if (IsAnonymousStoreyMutateRequired)
+                                       ac = (ArrayContainer) ac.Mutate (CurrentAnonymousMethod.Storey.Mutator);
 
-                       return local.Block.Toplevel != CurrentBlock.Toplevel;
+                               ig.Emit (OpCodes.Newobj, ac.GetConstructor ());
+                       }
                }
-               
-               public void EmitMeta (ToplevelBlock b)
+
+               public void EmitArrayAddress (ArrayContainer ac)
                {
-                       b.EmitMeta (this);
+                       if (ac.Element.IsGenericParameter)
+                               ig.Emit (OpCodes.Readonly);
+
+                       if (ac.Rank > 1) {
+                               if (IsAnonymousStoreyMutateRequired)
+                                       ac = (ArrayContainer) ac.Mutate (CurrentAnonymousMethod.Storey.Mutator);
 
-                       if (HasReturnLabel)
-                               ReturnLabel = ig.DefineLabel ();
+                               ig.Emit (OpCodes.Call, ac.GetAddressMethod ());
+                       } else {
+                               Emit (OpCodes.Ldelema, ac.Element);
+                       }
                }
 
                //
-               // Here until we can fix the problem with Mono.CSharp.Switch, which
-               // currently can not cope with ig == null during resolve (which must
-               // be fixed for switch statements to work on anonymous methods).
+               // Emits the right opcode to load from an array
                //
-               public void EmitTopBlock (IMethodData md, ToplevelBlock block)
+               public void EmitArrayLoad (ArrayContainer ac)
                {
-                       if (block == null)
+                       if (ac.Rank > 1) {
+                               if (IsAnonymousStoreyMutateRequired)
+                                       ac = (ArrayContainer) ac.Mutate (CurrentAnonymousMethod.Storey.Mutator);
+
+                               ig.Emit (OpCodes.Call, ac.GetGetMethod ());
                                return;
-                       
-                       bool unreachable;
-                       
-                       if (ResolveTopBlock (null, block, md.ParameterInfo, md, out unreachable)){
-                               if (Report.Errors > 0)
-                                       return;
+                       }
 
-                               EmitMeta (block);
+                       var type = ac.Element;
+                       if (TypeManager.IsEnumType (type))
+                               type = EnumSpec.GetUnderlyingType (type);
+
+                       if (type == TypeManager.byte_type || type == TypeManager.bool_type)
+                               Emit (OpCodes.Ldelem_U1);
+                       else if (type == TypeManager.sbyte_type)
+                               Emit (OpCodes.Ldelem_I1);
+                       else if (type == TypeManager.short_type)
+                               Emit (OpCodes.Ldelem_I2);
+                       else if (type == TypeManager.ushort_type || type == TypeManager.char_type)
+                               Emit (OpCodes.Ldelem_U2);
+                       else if (type == TypeManager.int32_type)
+                               Emit (OpCodes.Ldelem_I4);
+                       else if (type == TypeManager.uint32_type)
+                               Emit (OpCodes.Ldelem_U4);
+                       else if (type == TypeManager.uint64_type)
+                               Emit (OpCodes.Ldelem_I8);
+                       else if (type == TypeManager.int64_type)
+                               Emit (OpCodes.Ldelem_I8);
+                       else if (type == TypeManager.float_type)
+                               Emit (OpCodes.Ldelem_R4);
+                       else if (type == TypeManager.double_type)
+                               Emit (OpCodes.Ldelem_R8);
+                       else if (type == TypeManager.intptr_type)
+                               Emit (OpCodes.Ldelem_I);
+                       else if (TypeManager.IsStruct (type)) {
+                               Emit (OpCodes.Ldelema, type);
+                               Emit (OpCodes.Ldobj, type);
+                       } else if (type.IsGenericParameter) {
+                               Emit (OpCodes.Ldelem, type);
+                       } else if (type.IsPointer)
+                               Emit (OpCodes.Ldelem_I);
+                       else
+                               Emit (OpCodes.Ldelem_Ref);
+               }
 
-                               current_phase = Phase.Emitting;
-#if PRODUCTION
-                               try {
-#endif
-                               EmitResolvedTopBlock (block, unreachable);
-#if PRODUCTION
-                               } catch (Exception e){
-                                       Console.WriteLine ("Exception caught by the compiler while emitting:");
-                                       Console.WriteLine ("   Block that caused the problem begin at: " + block.loc);
-                                       
-                                       Console.WriteLine (e.GetType ().FullName + ": " + e.Message);
-                                       throw;
-                               }
-#endif
+               //
+               // Emits the right opcode to store to an array
+               //
+               public void EmitArrayStore (ArrayContainer ac)
+               {
+                       if (ac.Rank > 1) {
+                               if (IsAnonymousStoreyMutateRequired)
+                                       ac = (ArrayContainer) ac.Mutate (CurrentAnonymousMethod.Storey.Mutator);
+
+                               ig.Emit (OpCodes.Call, ac.GetSetMethod ());
+                               return;
                        }
-               }
 
-               bool resolved;
-               bool unreachable;
+                       var type = ac.Element;
+
+                       if (type.IsEnum)
+                               type = EnumSpec.GetUnderlyingType (type);
+
+                       if (type == TypeManager.byte_type || type == TypeManager.sbyte_type || type == TypeManager.bool_type)
+                               Emit (OpCodes.Stelem_I1);
+                       else if (type == TypeManager.short_type || type == TypeManager.ushort_type || type == TypeManager.char_type)
+                               Emit (OpCodes.Stelem_I2);
+                       else if (type == TypeManager.int32_type || type == TypeManager.uint32_type)
+                               Emit (OpCodes.Stelem_I4);
+                       else if (type == TypeManager.int64_type || type == TypeManager.uint64_type)
+                               Emit (OpCodes.Stelem_I8);
+                       else if (type == TypeManager.float_type)
+                               Emit (OpCodes.Stelem_R4);
+                       else if (type == TypeManager.double_type)
+                               Emit (OpCodes.Stelem_R8);
+                       else if (type == TypeManager.intptr_type)
+                               Emit (OpCodes.Stobj, type);
+                       else if (TypeManager.IsStruct (type))
+                               Emit (OpCodes.Stobj, type);
+                       else if (type.IsGenericParameter)
+                               Emit (OpCodes.Stelem, type);
+                       else if (type.IsPointer)
+                               Emit (OpCodes.Stelem_I);
+                       else
+                               Emit (OpCodes.Stelem_Ref);
+               }
 
-               public bool ResolveTopBlock (EmitContext anonymous_method_host, ToplevelBlock block,
-                                            ParametersCompiled ip, IMethodData md, out bool unreachable)
+               public void EmitInt (int i)
                {
-                       if (resolved) {
-                               unreachable = this.unreachable;
-                               return true;
-                       }
+                       switch (i) {
+                       case -1:
+                               ig.Emit (OpCodes.Ldc_I4_M1);
+                               break;
 
-                       current_phase = Phase.Resolving;
-                       unreachable = false;
+                       case 0:
+                               ig.Emit (OpCodes.Ldc_I4_0);
+                               break;
 
-                       if (!loc.IsNull)
-                               CurrentFile = loc.File;
+                       case 1:
+                               ig.Emit (OpCodes.Ldc_I4_1);
+                               break;
 
-#if PRODUCTION
-                       try {
-#endif
-                               if (!block.ResolveMeta (this, ip))
-                                       return false;
-
-                               using (this.With (EmitContext.Flags.DoFlowAnalysis, true)) {
-                                       FlowBranchingToplevel top_level;
-                                       if (anonymous_method_host != null)
-                                               top_level = new FlowBranchingToplevel (anonymous_method_host.CurrentBranching, block);
-                                       else 
-                                               top_level = block.TopLevelBranching;
-
-                                       current_flow_branching = top_level;
-                                       bool ok = block.Resolve (this);
-                                       current_flow_branching = null;
-
-                                       if (!ok)
-                                               return false;
-
-                                       bool flow_unreachable = top_level.End ();
-                                       if (flow_unreachable)
-                                               this.unreachable = unreachable = true;
-                               }
-#if PRODUCTION
-                       } catch (Exception e) {
-                               Console.WriteLine ("Exception caught by the compiler while compiling:");
-                               Console.WriteLine ("   Block that caused the problem begin at: " + loc);
-
-                               if (CurrentBlock != null){
-                                       Console.WriteLine ("                     Block being compiled: [{0},{1}]",
-                                                          CurrentBlock.StartLocation, CurrentBlock.EndLocation);
-                               }
-                               Console.WriteLine (e.GetType ().FullName + ": " + e.Message);
-                               throw;
-                       }
-#endif
+                       case 2:
+                               ig.Emit (OpCodes.Ldc_I4_2);
+                               break;
 
-                       if (return_type != TypeManager.void_type && !unreachable) {
-                               if (CurrentAnonymousMethod == null) {
-                                       Report.Error (161, md.Location, "`{0}': not all code paths return a value", md.GetSignatureForError ());
-                                       return false;
-                               } else if (!CurrentAnonymousMethod.IsIterator) {
-                                       Report.Error (1643, CurrentAnonymousMethod.Location, "Not all code paths return a value in anonymous method of type `{0}'",
-                                                     CurrentAnonymousMethod.GetSignatureForError ());
-                                       return false;
-                               }
-                       }
+                       case 3:
+                               ig.Emit (OpCodes.Ldc_I4_3);
+                               break;
 
-                       resolved = true;
-                       return true;
-               }
+                       case 4:
+                               ig.Emit (OpCodes.Ldc_I4_4);
+                               break;
 
-               public Type ReturnType {
-                       set {
-                               return_type = value;
-                       }
-                       get {
-                               return return_type;
-                       }
-               }
+                       case 5:
+                               ig.Emit (OpCodes.Ldc_I4_5);
+                               break;
 
-               public void EmitResolvedTopBlock (ToplevelBlock block, bool unreachable)
-               {
-                       if (block != null)
-                               block.Emit (this);
+                       case 6:
+                               ig.Emit (OpCodes.Ldc_I4_6);
+                               break;
 
-                       if (HasReturnLabel)
-                               ig.MarkLabel (ReturnLabel);
+                       case 7:
+                               ig.Emit (OpCodes.Ldc_I4_7);
+                               break;
 
-                       if (return_value != null){
-                               ig.Emit (OpCodes.Ldloc, return_value);
-                               ig.Emit (OpCodes.Ret);
-                       } else {
-                               //
-                               // If `HasReturnLabel' is set, then we already emitted a
-                               // jump to the end of the method, so we must emit a `ret'
-                               // there.
-                               //
-                               // Unfortunately, System.Reflection.Emit automatically emits
-                               // a leave to the end of a finally block.  This is a problem
-                               // if no code is following the try/finally block since we may
-                               // jump to a point after the end of the method.
-                               // As a workaround, we're always creating a return label in
-                               // this case.
-                               //
-
-                               if (HasReturnLabel || !unreachable) {
-                                       if (return_type != TypeManager.void_type)
-                                               ig.Emit (OpCodes.Ldloc, TemporaryReturn ());
-                                       ig.Emit (OpCodes.Ret);
-                               }
+                       case 8:
+                               ig.Emit (OpCodes.Ldc_I4_8);
+                               break;
+
+                       default:
+                               if (i >= -128 && i <= 127) {
+                                       ig.Emit (OpCodes.Ldc_I4_S, (sbyte) i);
+                               } else
+                                       ig.Emit (OpCodes.Ldc_I4, i);
+                               break;
                        }
                }
 
-               /// <summary>
-               ///   This is called immediately before emitting an IL opcode to tell the symbol
-               ///   writer to which source line this opcode belongs.
-               /// </summary>
-               public void Mark (Location loc)
+               public void EmitLong (long l)
                {
-                       if (!SymbolWriter.HasSymbolWriter || OmitDebuggingInfo || loc.IsNull)
+                       if (l >= int.MinValue && l <= int.MaxValue) {
+                               EmitInt (unchecked ((int) l));
+                               ig.Emit (OpCodes.Conv_I8);
                                return;
+                       }
 
-                       SymbolWriter.MarkSequencePoint (ig, loc);
-               }
+                       if (l >= 0 && l <= uint.MaxValue) {
+                               EmitInt (unchecked ((int) l));
+                               ig.Emit (OpCodes.Conv_U8);
+                               return;
+                       }
 
-               public void DefineLocalVariable (string name, LocalBuilder builder)
-               {
-                       SymbolWriter.DefineLocalVariable (name, builder);
+                       ig.Emit (OpCodes.Ldc_I8, l);
                }
 
-               public void BeginScope ()
-               {
-                       ig.BeginScope();
-                       SymbolWriter.OpenScope(ig);
+               //
+               // Load the object from the pointer.  
+               //
+               public void EmitLoadFromPtr (TypeSpec t)
+               {
+                       if (t == TypeManager.int32_type)
+                               ig.Emit (OpCodes.Ldind_I4);
+                       else if (t == TypeManager.uint32_type)
+                               ig.Emit (OpCodes.Ldind_U4);
+                       else if (t == TypeManager.short_type)
+                               ig.Emit (OpCodes.Ldind_I2);
+                       else if (t == TypeManager.ushort_type)
+                               ig.Emit (OpCodes.Ldind_U2);
+                       else if (t == TypeManager.char_type)
+                               ig.Emit (OpCodes.Ldind_U2);
+                       else if (t == TypeManager.byte_type)
+                               ig.Emit (OpCodes.Ldind_U1);
+                       else if (t == TypeManager.sbyte_type)
+                               ig.Emit (OpCodes.Ldind_I1);
+                       else if (t == TypeManager.uint64_type)
+                               ig.Emit (OpCodes.Ldind_I8);
+                       else if (t == TypeManager.int64_type)
+                               ig.Emit (OpCodes.Ldind_I8);
+                       else if (t == TypeManager.float_type)
+                               ig.Emit (OpCodes.Ldind_R4);
+                       else if (t == TypeManager.double_type)
+                               ig.Emit (OpCodes.Ldind_R8);
+                       else if (t == TypeManager.bool_type)
+                               ig.Emit (OpCodes.Ldind_I1);
+                       else if (t == TypeManager.intptr_type)
+                               ig.Emit (OpCodes.Ldind_I);
+                       else if (t.IsEnum) {
+                               if (t == TypeManager.enum_type)
+                                       ig.Emit (OpCodes.Ldind_Ref);
+                               else
+                                       EmitLoadFromPtr (EnumSpec.GetUnderlyingType (t));
+                       } else if (TypeManager.IsStruct (t) || TypeManager.IsGenericParameter (t))
+                               Emit (OpCodes.Ldobj, t);
+                       else if (t.IsPointer)
+                               ig.Emit (OpCodes.Ldind_I);
+                       else
+                               ig.Emit (OpCodes.Ldind_Ref);
                }
 
-               public void EndScope ()
-               {
-                       ig.EndScope();
-                       SymbolWriter.CloseScope(ig);
+               //
+               // The stack contains the pointer and the value of type `type'
+               //
+               public void EmitStoreFromPtr (TypeSpec type)
+               {
+                       if (type.IsEnum)
+                               type = EnumSpec.GetUnderlyingType (type);
+
+                       if (type == TypeManager.int32_type || type == TypeManager.uint32_type)
+                               ig.Emit (OpCodes.Stind_I4);
+                       else if (type == TypeManager.int64_type || type == TypeManager.uint64_type)
+                               ig.Emit (OpCodes.Stind_I8);
+                       else if (type == TypeManager.char_type || type == TypeManager.short_type ||
+                                type == TypeManager.ushort_type)
+                               ig.Emit (OpCodes.Stind_I2);
+                       else if (type == TypeManager.float_type)
+                               ig.Emit (OpCodes.Stind_R4);
+                       else if (type == TypeManager.double_type)
+                               ig.Emit (OpCodes.Stind_R8);
+                       else if (type == TypeManager.byte_type || type == TypeManager.sbyte_type ||
+                                type == TypeManager.bool_type)
+                               ig.Emit (OpCodes.Stind_I1);
+                       else if (type == TypeManager.intptr_type)
+                               ig.Emit (OpCodes.Stind_I);
+                       else if (TypeManager.IsStruct (type) || TypeManager.IsGenericParameter (type))
+                               Emit (OpCodes.Stobj, type);
+                       else
+                               ig.Emit (OpCodes.Stind_Ref);
                }
 
                /// <summary>
                ///   Returns a temporary storage for a variable of type t as 
                ///   a local variable in the current body.
                /// </summary>
-               public LocalBuilder GetTemporaryLocal (Type t)
+               public LocalBuilder GetTemporaryLocal (TypeSpec t)
                {
                        if (temporary_storage != null) {
-                               object o = temporary_storage [t];
-                               if (o != null) {
-                                       if (o is Stack) {
-                                               Stack s = (Stack) o;
+                               object o;
+                               if (temporary_storage.TryGetValue (t, out o)) {
+                                       if (o is Stack<LocalBuilder>) {
+                                               var s = (Stack<LocalBuilder>) o;
                                                o = s.Count == 0 ? null : s.Pop ();
                                        } else {
                                                temporary_storage.Remove (t);
@@ -924,46 +601,31 @@ namespace Mono.CSharp {
                                if (o != null)
                                        return (LocalBuilder) o;
                        }
-                       return ig.DeclareLocal (t);
+                       return DeclareLocal (t, false);
                }
 
-               public void FreeTemporaryLocal (LocalBuilder b, Type t)
+               public void FreeTemporaryLocal (LocalBuilder b, TypeSpec t)
                {
                        if (temporary_storage == null) {
-                               temporary_storage = new Hashtable ();
-                               temporary_storage [t] = b;
+                               temporary_storage = new Dictionary<TypeSpec, object> (ReferenceEquality<TypeSpec>.Default);
+                               temporary_storage.Add (t, b);
                                return;
                        }
-                       object o = temporary_storage [t];
-                       if (o == null) {
-                               temporary_storage [t] = b;
+                       object o;
+                       
+                       if (!temporary_storage.TryGetValue (t, out o)) {
+                               temporary_storage.Add (t, b);
                                return;
                        }
-                       Stack s = o as Stack;
+                       var s = o as Stack<LocalBuilder>;
                        if (s == null) {
-                               s = new Stack ();
-                               s.Push (o);
+                               s = new Stack<LocalBuilder> ();
+                               s.Push ((LocalBuilder)o);
                                temporary_storage [t] = s;
                        }
                        s.Push (b);
                }
 
-               /// <summary>
-               ///   Current loop begin and end labels.
-               /// </summary>
-               public Label LoopBegin, LoopEnd;
-
-               /// <summary>
-               ///   Default target in a switch statement.   Only valid if
-               ///   InSwitch is true
-               /// </summary>
-               public Label DefaultTarget;
-
-               /// <summary>
-               ///   If this is non-null, points to the current switch statement
-               /// </summary>
-               public Switch Switch;
-
                /// <summary>
                ///   ReturnValue creates on demand the LocalBuilder for the
                ///   return value from the function.  By default this is not
@@ -979,592 +641,14 @@ namespace Mono.CSharp {
                public LocalBuilder TemporaryReturn ()
                {
                        if (return_value == null){
-                               return_value = ig.DeclareLocal (return_type);
+                               return_value = DeclareLocal (return_type, false);
                                if (!HasReturnLabel){
-                                       ReturnLabel = ig.DefineLabel ();
+                                       ReturnLabel = DefineLabel ();
                                        HasReturnLabel = true;
                                }
                        }
 
                        return return_value;
                }
-
-               /// <summary>
-               ///   This method is used during the Resolution phase to flag the
-               ///   need to define the ReturnLabel
-               /// </summary>
-               public void NeedReturnLabel ()
-               {
-                       if (current_phase != Phase.Resolving){
-                               //
-                               // The reason is that the `ReturnLabel' is declared between
-                               // resolution and emission
-                               // 
-                               throw new Exception ("NeedReturnLabel called from Emit phase, should only be called during Resolve");
-                       }
-                       
-                       if (!HasReturnLabel)
-                               HasReturnLabel = true;
-               }
-
-
-               public Expression GetThis (Location loc)
-               {
-                       This my_this;
-                       if (CurrentBlock != null)
-                               my_this = new This (CurrentBlock, loc);
-                       else
-                               my_this = new This (loc);
-
-                       if (!my_this.ResolveBase (this))
-                               my_this = null;
-
-                       return my_this;
-               }
-       }
-
-
-       public abstract class CommonAssemblyModulClass : Attributable, IResolveContext {
-
-               protected CommonAssemblyModulClass ():
-                       base (null)
-               {
-               }
-
-               public void AddAttributes (ArrayList attrs)
-               {
-                       foreach (Attribute a in attrs)
-                               a.AttachTo (this);
-
-                       if (attributes == null) {
-                               attributes = new Attributes (attrs);
-                               return;
-                       }
-                       attributes.AddAttributes (attrs);
-               }
-
-               public virtual void Emit (TypeContainer tc) 
-               {
-                       if (OptAttributes == null)
-                               return;
-
-                       OptAttributes.Emit ();
-               }
-
-               protected Attribute ResolveAttribute (PredefinedAttribute a_type)
-               {
-                       Attribute a = OptAttributes.Search (a_type);
-                       if (a != null) {
-                               a.Resolve ();
-                       }
-                       return a;
-               }
-
-               public override IResolveContext ResolveContext {
-                       get { return this; }
-               }
-
-               #region IResolveContext Members
-
-               public DeclSpace DeclContainer {
-                       get { return RootContext.ToplevelTypes; }
-               }
-
-               public DeclSpace GenericDeclContainer {
-                       get { return DeclContainer; }
-               }
-
-               public bool IsInObsoleteScope {
-                       get { return false; }
-               }
-
-               public bool IsInUnsafeScope {
-                       get { return false; }
-               }
-
-               #endregion
-       }
-                
-       public class AssemblyClass : CommonAssemblyModulClass {
-               // TODO: make it private and move all builder based methods here
-               public AssemblyBuilder Builder;
-               bool is_cls_compliant;
-               bool wrap_non_exception_throws;
-
-               public Attribute ClsCompliantAttribute;
-
-               ListDictionary declarative_security;
-#if GMCS_SOURCE
-               bool has_extension_method;              
-               public AssemblyName Name;
-               MethodInfo add_type_forwarder;
-               ListDictionary emitted_forwarders;
-#endif
-
-               // Module is here just because of error messages
-               static string[] attribute_targets = new string [] { "assembly", "module" };
-
-               public AssemblyClass (): base ()
-               {
-#if GMCS_SOURCE
-                       wrap_non_exception_throws = true;
-#endif
-               }
-
-               public bool HasExtensionMethods {
-                       set {
-#if GMCS_SOURCE                                
-                               has_extension_method = value;
-#endif
-                       }
-               }
-
-               public bool IsClsCompliant {
-                       get {
-                               return is_cls_compliant;
-                       }
-               }
-
-               public bool WrapNonExceptionThrows {
-                       get {
-                               return wrap_non_exception_throws;
-                       }
-               }
-
-               public override AttributeTargets AttributeTargets {
-                       get {
-                               return AttributeTargets.Assembly;
-                       }
-               }
-
-               public override bool IsClsComplianceRequired ()
-               {
-                       return is_cls_compliant;
-               }
-
-               public void Resolve ()
-               {
-                       if (RootContext.Unsafe) {
-                               //
-                               // Emits [assembly: SecurityPermissionAttribute (SecurityAction.RequestMinimum, SkipVerification = true)]
-                               // when -unsafe option was specified
-                               //
-                               
-                               Location loc = Location.Null;
-
-                               MemberAccess system_security_permissions = new MemberAccess (new MemberAccess (
-                                       new QualifiedAliasMember (QualifiedAliasMember.GlobalAlias, "System", loc), "Security", loc), "Permissions", loc);
-
-                               ArrayList pos = new ArrayList (1);
-                               pos.Add (new Argument (new MemberAccess (new MemberAccess (system_security_permissions, "SecurityAction", loc), "RequestMinimum")));
-
-                               ArrayList named = new ArrayList (1);
-                               named.Add (new DictionaryEntry ("SkipVerification", new Argument (new BoolLiteral (true, loc))));
-
-                               GlobalAttribute g = new GlobalAttribute (new NamespaceEntry (null, null, null), "assembly", system_security_permissions,
-                                       "SecurityPermissionAttribute", new object[] { pos, named }, loc, false);
-                               g.AttachTo (this);
-
-                               if (g.Resolve () != null) {
-                                       declarative_security = new ListDictionary ();
-                                       g.ExtractSecurityPermissionSet (declarative_security);
-                               }
-                       }
-
-                       if (OptAttributes == null)
-                               return;
-
-                       // Ensure that we only have GlobalAttributes, since the Search isn't safe with other types.
-                       if (!OptAttributes.CheckTargets())
-                               return;
-
-                       ClsCompliantAttribute = ResolveAttribute (PredefinedAttributes.Get.CLSCompliant);
-
-                       if (ClsCompliantAttribute != null) {
-                               is_cls_compliant = ClsCompliantAttribute.GetClsCompliantAttributeValue ();
-                       }
-
-                       Attribute a = ResolveAttribute (PredefinedAttributes.Get.RuntimeCompatibility);
-                       if (a != null) {
-                               object val = a.GetPropertyValue ("WrapNonExceptionThrows");
-                               if (val != null)
-                                       wrap_non_exception_throws = (bool) val;
-                       }
-               }
-
-               // fix bug #56621
-               private void SetPublicKey (AssemblyName an, byte[] strongNameBlob) 
-               {
-                       try {
-                               // check for possible ECMA key
-                               if (strongNameBlob.Length == 16) {
-                                       // will be rejected if not "the" ECMA key
-                                       an.SetPublicKey (strongNameBlob);
-                               }
-                               else {
-                                       // take it, with or without, a private key
-                                       RSA rsa = CryptoConvert.FromCapiKeyBlob (strongNameBlob);
-                                       // and make sure we only feed the public part to Sys.Ref
-                                       byte[] publickey = CryptoConvert.ToCapiPublicKeyBlob (rsa);
-                                       
-                                       // AssemblyName.SetPublicKey requires an additional header
-                                       byte[] publicKeyHeader = new byte [12] { 0x00, 0x24, 0x00, 0x00, 0x04, 0x80, 0x00, 0x00, 0x94, 0x00, 0x00, 0x00 };
-
-                                       byte[] encodedPublicKey = new byte [12 + publickey.Length];
-                                       Buffer.BlockCopy (publicKeyHeader, 0, encodedPublicKey, 0, 12);
-                                       Buffer.BlockCopy (publickey, 0, encodedPublicKey, 12, publickey.Length);
-                                       an.SetPublicKey (encodedPublicKey);
-                               }
-                       }
-                       catch (Exception) {
-                               Error_AssemblySigning ("The specified file `" + RootContext.StrongNameKeyFile + "' is incorrectly encoded");
-                               Environment.Exit (1);
-                       }
-               }
-
-               // TODO: rewrite this code (to kill N bugs and make it faster) and use standard ApplyAttribute way.
-               public AssemblyName GetAssemblyName (string name, string output) 
-               {
-                       if (OptAttributes != null) {
-                               foreach (Attribute a in OptAttributes.Attrs) {
-                                       // cannot rely on any resolve-based members before you call Resolve
-                                       if (a.ExplicitTarget == null || a.ExplicitTarget != "assembly")
-                                               continue;
-
-                                       // TODO: This code is buggy: comparing Attribute name without resolving is wrong.
-                                       //       However, this is invoked by CodeGen.Init, when none of the namespaces
-                                       //       are loaded yet.
-                                       // TODO: Does not handle quoted attributes properly
-                                       switch (a.Name) {
-                                       case "AssemblyKeyFile":
-                                       case "AssemblyKeyFileAttribute":
-                                       case "System.Reflection.AssemblyKeyFileAttribute":
-                                               if (RootContext.StrongNameKeyFile != null) {
-                                                       Report.SymbolRelatedToPreviousError (a.Location, a.Name);
-                                                       Report.Warning (1616, 1, "Option `{0}' overrides attribute `{1}' given in a source file or added module",
-                                                                       "keyfile", "System.Reflection.AssemblyKeyFileAttribute");
-                                               } else {
-                                                       string value = a.GetString ();
-                                                       if (value.Length != 0)
-                                                               RootContext.StrongNameKeyFile = value;
-                                               }
-                                               break;
-                                       case "AssemblyKeyName":
-                                       case "AssemblyKeyNameAttribute":
-                                       case "System.Reflection.AssemblyKeyNameAttribute":
-                                               if (RootContext.StrongNameKeyContainer != null) {
-                                                       Report.SymbolRelatedToPreviousError (a.Location, a.Name);
-                                                       Report.Warning (1616, 1, "Option `{0}' overrides attribute `{1}' given in a source file or added module",
-                                                                       "keycontainer", "System.Reflection.AssemblyKeyNameAttribute");
-                                               } else {
-                                                       string value = a.GetString ();
-                                                       if (value.Length != 0)
-                                                               RootContext.StrongNameKeyContainer = value;
-                                               }
-                                               break;
-                                       case "AssemblyDelaySign":
-                                       case "AssemblyDelaySignAttribute":
-                                       case "System.Reflection.AssemblyDelaySignAttribute":
-                                               RootContext.StrongNameDelaySign = a.GetBoolean ();
-                                               break;
-                                       }
-                               }
-                       }
-                       
-                       AssemblyName an = new AssemblyName ();
-                       an.Name = Path.GetFileNameWithoutExtension (name);
-
-                       // note: delay doesn't apply when using a key container
-                       if (RootContext.StrongNameKeyContainer != null) {
-                               an.KeyPair = new StrongNameKeyPair (RootContext.StrongNameKeyContainer);
-                               return an;
-                       }
-
-                       // strongname is optional
-                       if (RootContext.StrongNameKeyFile == null)
-                               return an;
-
-                       string AssemblyDir = Path.GetDirectoryName (output);
-
-                       // the StrongName key file may be relative to (a) the compiled
-                       // file or (b) to the output assembly. See bugzilla #55320
-                       // http://bugzilla.ximian.com/show_bug.cgi?id=55320
-
-                       // (a) relative to the compiled file
-                       string filename = Path.GetFullPath (RootContext.StrongNameKeyFile);
-                       bool exist = File.Exists (filename);
-                       if ((!exist) && (AssemblyDir != null) && (AssemblyDir != String.Empty)) {
-                               // (b) relative to the outputed assembly
-                               filename = Path.GetFullPath (Path.Combine (AssemblyDir, RootContext.StrongNameKeyFile));
-                               exist = File.Exists (filename);
-                       }
-
-                       if (exist) {
-                               using (FileStream fs = new FileStream (filename, FileMode.Open, FileAccess.Read)) {
-                                       byte[] snkeypair = new byte [fs.Length];
-                                       fs.Read (snkeypair, 0, snkeypair.Length);
-
-                                       if (RootContext.StrongNameDelaySign) {
-                                               // delayed signing - DO NOT include private key
-                                               SetPublicKey (an, snkeypair);
-                                       }
-                                       else {
-                                               // no delay so we make sure we have the private key
-                                               try {
-                                                       CryptoConvert.FromCapiPrivateKeyBlob (snkeypair);
-                                                       an.KeyPair = new StrongNameKeyPair (snkeypair);
-                                               }
-                                               catch (CryptographicException) {
-                                                       if (snkeypair.Length == 16) {
-                                                               // error # is different for ECMA key
-                                                               Report.Error (1606, "Could not sign the assembly. " + 
-                                                                       "ECMA key can only be used to delay-sign assemblies");
-                                                       }
-                                                       else {
-                                                               Error_AssemblySigning ("The specified file `" + RootContext.StrongNameKeyFile + "' does not have a private key");
-                                                       }
-                                                       return null;
-                                               }
-                                       }
-                               }
-                       }
-                       else {
-                               Error_AssemblySigning ("The specified file `" + RootContext.StrongNameKeyFile + "' does not exist");
-                               return null;
-                       }
-                       return an;
-               }
-
-               void Error_AssemblySigning (string text)
-               {
-                       Report.Error (1548, "Error during assembly signing. " + text);
-               }
-
-#if GMCS_SOURCE
-               bool CheckInternalsVisibleAttribute (Attribute a)
-               {
-                       string assembly_name = a.GetString ();
-                       if (assembly_name.Length == 0)
-                               return false;
-                               
-                       AssemblyName aname = null;
-                       try {
-                               aname = new AssemblyName (assembly_name);
-                       } catch (FileLoadException) {
-                       } catch (ArgumentException) {
-                       }
-                               
-                       // Bad assembly name format
-                       if (aname == null)
-                               Report.Warning (1700, 3, a.Location, "Assembly reference `" + assembly_name + "' is invalid and cannot be resolved");
-                       // Report error if we have defined Version or Culture
-                       else if (aname.Version != null || aname.CultureInfo != null)
-                               throw new Exception ("Friend assembly `" + a.GetString () + 
-                                               "' is invalid. InternalsVisibleTo cannot have version or culture specified.");
-                       else if (aname.GetPublicKey () == null && Name.GetPublicKey () != null && Name.GetPublicKey ().Length != 0) {
-                               Report.Error (1726, a.Location, "Friend assembly reference `" + aname.FullName + "' is invalid." +
-                                               " Strong named assemblies must specify a public key in their InternalsVisibleTo declarations");
-                               return false;
-                       }
-
-                       return true;
-               }
-#endif
-
-               static bool IsValidAssemblyVersion (string version)
-               {
-                       Version v;
-                       try {
-                               v = new Version (version);
-                       } catch {
-                               try {
-                                       int major = int.Parse (version, CultureInfo.InvariantCulture);
-                                       v = new Version (major, 0);
-                               } catch {
-                                       return false;
-                               }
-                       }
-
-                       foreach (int candidate in new int [] { v.Major, v.Minor, v.Build, v.Revision }) {
-                               if (candidate > ushort.MaxValue)
-                                       return false;
-                       }
-
-                       return true;
-               }
-
-               public override void ApplyAttributeBuilder (Attribute a, CustomAttributeBuilder cb, PredefinedAttributes pa)
-               {
-                       if (a.IsValidSecurityAttribute ()) {
-                               if (declarative_security == null)
-                                       declarative_security = new ListDictionary ();
-
-                               a.ExtractSecurityPermissionSet (declarative_security);
-                               return;
-                       }
-
-                       if (a.Type == pa.AssemblyCulture) {
-                               string value = a.GetString ();
-                               if (value == null || value.Length == 0)
-                                       return;
-
-                               if (RootContext.Target == Target.Exe) {
-                                       a.Error_AttributeEmitError ("The executables cannot be satelite assemblies, remove the attribute or keep it empty");
-                                       return;
-                               }
-                       }
-
-                       if (a.Type == pa.AssemblyVersion) {
-                               string value = a.GetString ();
-                               if (value == null || value.Length == 0)
-                                       return;
-
-                               value = value.Replace ('*', '0');
-
-                               if (!IsValidAssemblyVersion (value)) {
-                                       a.Error_AttributeEmitError (string.Format ("Specified version `{0}' is not valid", value));
-                                       return;
-                               }
-                       }
-
-#if GMCS_SOURCE
-                       if (a.Type == pa.InternalsVisibleTo && !CheckInternalsVisibleAttribute (a))
-                               return;
-
-                       if (a.Type == pa.TypeForwarder) {
-                               Type t = a.GetArgumentType ();
-                               if (t == null || TypeManager.HasElementType (t)) {
-                                       Report.Error (735, a.Location, "Invalid type specified as an argument for TypeForwardedTo attribute");
-                                       return;
-                               }
-
-                               if (emitted_forwarders == null) {
-                                       emitted_forwarders = new ListDictionary();
-                               } else if (emitted_forwarders.Contains(t)) {
-                                       Report.SymbolRelatedToPreviousError(((Attribute)emitted_forwarders[t]).Location, null);
-                                       Report.Error(739, a.Location, "A duplicate type forward of type `{0}'",
-                                               TypeManager.CSharpName(t));
-                                       return;
-                               }
-
-                               emitted_forwarders.Add(t, a);
-
-                               if (TypeManager.LookupDeclSpace (t) != null) {
-                                       Report.SymbolRelatedToPreviousError (t);
-                                       Report.Error (729, a.Location, "Cannot forward type `{0}' because it is defined in this assembly",
-                                               TypeManager.CSharpName (t));
-                                       return;
-                               }
-
-                               if (t.IsNested) {
-                                       Report.Error (730, a.Location, "Cannot forward type `{0}' because it is a nested type",
-                                               TypeManager.CSharpName (t));
-                                       return;
-                               }
-
-                               if (t.IsGenericType) {
-                                       Report.Error (733, a.Location, "Cannot forward generic type `{0}'", TypeManager.CSharpName (t));
-                                       return;
-                               }
-
-                               if (add_type_forwarder == null) {
-                                       add_type_forwarder = typeof (AssemblyBuilder).GetMethod ("AddTypeForwarder",
-                                               BindingFlags.NonPublic | BindingFlags.Instance);
-
-                                       if (add_type_forwarder == null) {
-                                               Report.RuntimeMissingSupport (a.Location, "TypeForwardedTo attribute");
-                                               return;
-                                       }
-                               }
-
-                               add_type_forwarder.Invoke (Builder, new object[] { t });
-                               return;
-                       }
-                       
-                       if (a.Type == pa.Extension) {
-                               a.Error_MisusedExtensionAttribute ();
-                               return;
-                       }
-#endif
-                       Builder.SetCustomAttribute (cb);
-               }
-
-               public override void Emit (TypeContainer tc)
-               {
-                       base.Emit (tc);
-
-#if GMCS_SOURCE
-                       if (has_extension_method)
-                               PredefinedAttributes.Get.Extension.EmitAttribute (Builder);
-#endif
-
-                       // FIXME: Does this belong inside SRE.AssemblyBuilder instead?
-                       PredefinedAttribute pa = PredefinedAttributes.Get.RuntimeCompatibility;
-                       if (pa.IsDefined && (OptAttributes == null || !OptAttributes.Contains (pa))) {
-                               ConstructorInfo ci = TypeManager.GetPredefinedConstructor (
-                                       pa.Type, Location.Null, Type.EmptyTypes);
-                               PropertyInfo [] pis = new PropertyInfo [1];
-                               pis [0] = TypeManager.GetPredefinedProperty (pa.Type,
-                                       "WrapNonExceptionThrows", Location.Null, TypeManager.bool_type);
-                               object [] pargs = new object [1];
-                               pargs [0] = true;
-                               Builder.SetCustomAttribute (new CustomAttributeBuilder (ci, new object [0], pis, pargs));
-                       }
-
-                       if (declarative_security != null) {
-
-                               MethodInfo add_permission = typeof (AssemblyBuilder).GetMethod ("AddPermissionRequests", BindingFlags.Instance | BindingFlags.NonPublic);
-                               object builder_instance = Builder;
-
-                               try {
-                                       // Microsoft runtime hacking
-                                       if (add_permission == null) {
-                                               Type assembly_builder = typeof (AssemblyBuilder).Assembly.GetType ("System.Reflection.Emit.AssemblyBuilderData");
-                                               add_permission = assembly_builder.GetMethod ("AddPermissionRequests", BindingFlags.Instance | BindingFlags.NonPublic);
-
-                                               FieldInfo fi = typeof (AssemblyBuilder).GetField ("m_assemblyData", BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.GetField);
-                                               builder_instance = fi.GetValue (Builder);
-                                       }
-
-                                       object[] args = new object [] { declarative_security [SecurityAction.RequestMinimum],
-                                                                                                 declarative_security [SecurityAction.RequestOptional],
-                                                                                                 declarative_security [SecurityAction.RequestRefuse] };
-                                       add_permission.Invoke (builder_instance, args);
-                               }
-                               catch {
-                                       Report.RuntimeMissingSupport (Location.Null, "assembly permission setting");
-                               }
-                       }
-               }
-
-               public override string[] ValidAttributeTargets {
-                       get {
-                               return attribute_targets;
-                       }
-               }
-
-               // Wrapper for AssemblyBuilder.AddModule
-               static MethodInfo adder_method;
-               static public MethodInfo AddModule_Method {
-                       get {
-                               if (adder_method == null)
-                                       adder_method = typeof (AssemblyBuilder).GetMethod ("AddModule", BindingFlags.Instance|BindingFlags.NonPublic);
-                               return adder_method;
-                       }
-               }
-               public Module AddModule (string module)
-               {
-                       MethodInfo m = AddModule_Method;
-                       if (m == null) {
-                               Report.RuntimeMissingSupport (Location.Null, "/addmodule");
-                               Environment.Exit (1);
-                       }
-
-                       try {
-                               return (Module) m.Invoke (Builder, new object [] { module });
-                       } catch (TargetInvocationException ex) {
-                               throw ex.InnerException;
-                       }
-               }               
        }
 }