2005-10-24 Martin Baulig <martin@ximian.com>
[mono.git] / mcs / gmcs / constant.cs
index 73de93f06f273af931fca1d08ccc103eaea55966..608310c00adb7e2c8603f3eca0e1376af357eb4b 100644 (file)
@@ -3,6 +3,7 @@
 //
 // Author:
 //   Miguel de Icaza (miguel@ximian.com)
+//   Marek Safar (marek.safar@seznam.cz)
 //
 // (C) 2001 Ximian, Inc.
 //
@@ -17,6 +18,12 @@ namespace Mono.CSharp {
        ///   Base class for constants and literals.
        /// </summary>
        public abstract class Constant : Expression {
+
+               protected Constant (Location loc)
+               {
+                       this.loc = loc;
+               }
+
                /// <remarks>
                ///   This is different from ToString in that ToString
                ///   is supposed to be there for debugging purposes,
@@ -38,6 +45,11 @@ namespace Mono.CSharp {
                /// </summary>
                public abstract object GetValue ();
 
+               public virtual object GetTypedValue ()
+               {
+                       return GetValue ();
+               }
+
                /// <summary>
                ///   Constants are always born in a fully resolved state
                /// </summary>
@@ -62,7 +74,7 @@ namespace Mono.CSharp {
                        DoubleConstant c = ConvertToDouble ();
 
                        if (c == null)
-                               Convert.Error_CannotImplicitConversion (loc, Type, TypeManager.double_type);
+                               Error_ValueCannotBeConverted (loc, TypeManager.double_type, false);
 
                        return c;
                }
@@ -72,7 +84,7 @@ namespace Mono.CSharp {
                        FloatConstant c = ConvertToFloat ();
 
                        if (c == null)
-                               Convert.Error_CannotImplicitConversion (loc, Type, TypeManager.float_type);
+                               Error_ValueCannotBeConverted (loc, TypeManager.float_type, false);
 
                        return c;
                }
@@ -82,7 +94,7 @@ namespace Mono.CSharp {
                        ULongConstant c = ConvertToULong ();
 
                        if (c == null)
-                               Convert.Error_CannotImplicitConversion (loc, Type, TypeManager.uint64_type);
+                               Error_ValueCannotBeConverted (loc, TypeManager.uint64_type, false);
 
                        return c;
                }
@@ -92,7 +104,7 @@ namespace Mono.CSharp {
                        LongConstant c = ConvertToLong ();
 
                        if (c == null)
-                               Convert.Error_CannotImplicitConversion (loc, Type, TypeManager.int64_type);
+                               Error_ValueCannotBeConverted (loc, TypeManager.int64_type, false);
 
                        return c;
                }
@@ -102,7 +114,7 @@ namespace Mono.CSharp {
                        UIntConstant c = ConvertToUInt ();
 
                        if (c == null)
-                               Convert.Error_CannotImplicitConversion (loc, Type, TypeManager.uint32_type);
+                               Error_ValueCannotBeConverted (loc, TypeManager.uint32_type, false);
 
                        return c;
                }
@@ -112,7 +124,7 @@ namespace Mono.CSharp {
                        IntConstant c = ConvertToInt ();
 
                        if (c == null)
-                               Convert.Error_CannotImplicitConversion (loc, Type, TypeManager.int32_type);
+                               Error_ValueCannotBeConverted (loc, TypeManager.int32_type, false);
 
                        return c;
                }
@@ -122,11 +134,141 @@ namespace Mono.CSharp {
                        DecimalConstant c = ConvertToDecimal ();
 
                        if (c == null)
-                               Convert.Error_CannotConvertType (loc, Type, TypeManager.decimal_type);
+                               Error_ValueCannotBeConverted (loc, TypeManager.decimal_type, false);
 
                        return c;
                }
 
+               public virtual Constant ToType (Type type, Location loc)
+               {
+                       if (Type == type)
+                               return this;
+
+                       if (type == TypeManager.object_type)
+                               return this;
+
+                       if (!Convert.ImplicitStandardConversionExists (Convert.ConstantEC, this, type)){
+                               Error_ValueCannotBeConverted (loc, type, false);
+                               return null;
+                       }
+
+                       // Special-case: The 0 literal can be converted to an enum value,
+                       // and ImplicitStandardConversionExists will return true in that case.
+                       if (IsZeroInteger && Type == TypeManager.int32_type && TypeManager.IsEnumType (type)) {
+                               return new EnumConstant (this, type);
+                       }
+
+                       bool fail;                      
+                       object constant_value = TypeManager.ChangeType (GetValue (), type, out fail);
+                       if (fail){
+                               Error_ValueCannotBeConverted (loc, type, false);
+                               
+                               //
+                               // We should always catch the error before this is ever
+                               // reached, by calling Convert.ImplicitStandardConversionExists
+                               //
+                               throw new Exception (
+                                       String.Format ("LookupConstantValue: This should never be reached {0} {1}", Type, type));
+                       }
+
+                       Constant retval;
+                       if (type == TypeManager.int32_type)
+                               retval = new IntConstant ((int) constant_value, loc);
+                       else if (type == TypeManager.uint32_type)
+                               retval = new UIntConstant ((uint) constant_value, loc);
+                       else if (type == TypeManager.int64_type)
+                               retval = new LongConstant ((long) constant_value, loc);
+                       else if (type == TypeManager.uint64_type)
+                               retval = new ULongConstant ((ulong) constant_value, loc);
+                       else if (type == TypeManager.float_type)
+                               retval = new FloatConstant ((float) constant_value, loc);
+                       else if (type == TypeManager.double_type)
+                               retval = new DoubleConstant ((double) constant_value, loc);
+                       else if (type == TypeManager.string_type)
+                               retval = new StringConstant ((string) constant_value, loc);
+                       else if (type == TypeManager.short_type)
+                               retval = new ShortConstant ((short) constant_value, loc);
+                       else if (type == TypeManager.ushort_type)
+                               retval = new UShortConstant ((ushort) constant_value, loc);
+                       else if (type == TypeManager.sbyte_type)
+                               retval = new SByteConstant ((sbyte) constant_value, loc);
+                       else if (type == TypeManager.byte_type)
+                               retval = new ByteConstant ((byte) constant_value, loc);
+                       else if (type == TypeManager.char_type)
+                               retval = new CharConstant ((char) constant_value, loc);
+                       else if (type == TypeManager.bool_type)
+                               retval = new BoolConstant ((bool) constant_value, loc);
+                       else if (type == TypeManager.decimal_type)
+                               retval = new DecimalConstant ((decimal) constant_value, loc);
+                       else
+                               throw new Exception ("LookupConstantValue: Unhandled constant type: " + type);
+                       
+                       return retval;
+               }
+
+               protected void CheckRange (EmitContext ec, ulong value, Type type, ulong max)
+               {
+                       if (!ec.ConstantCheckState)
+                               return;
+
+                       if (value > max)
+                               throw new OverflowException ();
+               }
+
+               protected void CheckRange (EmitContext ec, double value, Type type, long min, long max)
+               {
+                       if (!ec.ConstantCheckState)
+                               return;
+
+                       if (((value < min) || (value > max)))
+                               throw new OverflowException ();
+               }
+
+               protected void CheckUnsigned (EmitContext ec, long value, Type type)
+               {
+                       if (!ec.ConstantCheckState)
+                               return;
+
+                       if (value < 0)
+                               throw new OverflowException ();
+               }
+
+               public abstract Constant Reduce (EmitContext ec, Type target_type);
+
+               /// <summary>
+               ///   Attempts to do a compile-time folding of a constant cast.
+               /// </summary>
+               public Constant TryReduce (EmitContext ec, Type target_type, Location loc)
+               {
+                       try {
+                               return  TryReduce (ec, target_type);
+                       }
+                       catch (OverflowException) {
+                               if (ec.ConstantCheckState) {
+                                       Report.Error (221, loc, "Constant value `{0}' cannot be converted to a `{1}' (use `unchecked' syntax to override)",
+                                               this.GetValue (), TypeManager.CSharpName (target_type));
+                               }
+                               return null;
+                       }
+               }
+
+               Constant TryReduce (EmitContext ec, Type target_type)
+               {
+                       if (Type == target_type)
+                               return this;
+
+                       if (TypeManager.IsEnumType (target_type)) {
+                               Constant c = TryReduce (ec, TypeManager.EnumToUnderlying (target_type));
+                               if (c == null)
+                                       return null;
+
+                               return new EnumConstant (c, target_type);
+                       }
+
+                       return Reduce (ec, target_type);
+               }
+
+
                public virtual DecimalConstant ConvertToDecimal ()
                {
                        return null;
@@ -161,7 +303,13 @@ namespace Mono.CSharp {
                {
                        return null;
                }
+
+               public abstract Constant Increment ();
                
+               public abstract bool IsDefaultValue {
+                       get;
+               }
+
                public abstract bool IsNegative {
                        get;
                }
@@ -178,7 +326,8 @@ namespace Mono.CSharp {
        public class BoolConstant : Constant {
                public readonly bool Value;
                
-               public BoolConstant (bool val)
+               public BoolConstant (bool val, Location loc):
+                       base (loc)
                {
                        type = TypeManager.bool_type;
                        eclass = ExprClass.Value;
@@ -204,7 +353,18 @@ namespace Mono.CSharp {
                        else
                                ec.ig.Emit (OpCodes.Ldc_I4_0);
                }
-               
+
+               public override Constant Increment ()
+               {
+                       throw new NotSupportedException ();
+               }
+       
+               public override bool IsDefaultValue {
+                       get {
+                               return !Value;
+                       }
+               }
+
                public override bool IsNegative {
                        get {
                                return false;
@@ -214,12 +374,19 @@ namespace Mono.CSharp {
                public override bool IsZeroInteger {
                        get { return Value == false; }
                }
+
+               public override Constant Reduce (EmitContext ec, Type target_type)
+               {
+                       return null;
+               }
+
        }
 
        public class ByteConstant : Constant {
                public readonly byte Value;
 
-               public ByteConstant (byte v)
+               public ByteConstant (byte v, Location loc):
+                       base (loc)
                {
                        type = TypeManager.byte_type;
                        eclass = ExprClass.Value;
@@ -243,34 +410,45 @@ namespace Mono.CSharp {
 
                public override DoubleConstant ConvertToDouble ()
                {
-                       return new DoubleConstant (Value);
+                       return new DoubleConstant (Value, loc);
                }
 
                public override FloatConstant ConvertToFloat ()
                {
-                       return new FloatConstant (Value);
+                       return new FloatConstant (Value, loc);
                }
 
                public override ULongConstant ConvertToULong ()
                {
-                       return new ULongConstant (Value);
+                       return new ULongConstant (Value, loc);
                }
 
                public override LongConstant ConvertToLong ()
                {
-                       return new LongConstant (Value);
+                       return new LongConstant (Value, loc);
                }
 
                public override UIntConstant ConvertToUInt ()
                {
-                       return new UIntConstant (Value);
+                       return new UIntConstant (Value, loc);
                }
 
                public override IntConstant ConvertToInt ()
                {
-                       return new IntConstant (Value);
+                       return new IntConstant (Value, loc);
                }
                
+               public override Constant Increment ()
+               {
+                       return new ByteConstant (checked ((byte)(Value + 1)), loc);
+               }
+
+               public override bool IsDefaultValue {
+                       get {
+                               return Value == 0;
+                       }
+               }
+
                public override bool IsNegative {
                        get {
                                return false;
@@ -280,12 +458,44 @@ namespace Mono.CSharp {
                public override bool IsZeroInteger {
                        get { return Value == 0; }
                }
+
+               public override Constant Reduce (EmitContext ec, Type target_type)
+               {
+                       if (target_type == TypeManager.sbyte_type) {
+                               CheckRange (ec, Value, target_type, SByte.MinValue, SByte.MaxValue);
+                               return new SByteConstant ((sbyte) Value, Location);
+                       }
+                       if (target_type == TypeManager.short_type)
+                               return new ShortConstant ((short) Value, Location);
+                       if (target_type == TypeManager.ushort_type)
+                               return new UShortConstant ((ushort) Value, Location);
+                       if (target_type == TypeManager.int32_type)
+                               return new IntConstant ((int) Value, Location);
+                       if (target_type == TypeManager.uint32_type)
+                               return new UIntConstant ((uint) Value, Location);
+                       if (target_type == TypeManager.int64_type)
+                               return new LongConstant ((long) Value, Location);
+                       if (target_type == TypeManager.uint64_type)
+                               return new ULongConstant ((ulong) Value, Location);
+                       if (target_type == TypeManager.float_type)
+                               return new FloatConstant ((float) Value, Location);
+                       if (target_type == TypeManager.double_type)
+                               return new DoubleConstant ((double) Value, Location);
+                       if (target_type == TypeManager.char_type)
+                               return new CharConstant ((char) Value, Location);
+                       if (target_type == TypeManager.decimal_type)
+                               return new DecimalConstant ((decimal) Value, Location);
+
+                       return null;
+               }
+
        }
 
        public class CharConstant : Constant {
                public readonly char Value;
 
-               public CharConstant (char v)
+               public CharConstant (char v, Location loc):
+                       base (loc)
                {
                        type = TypeManager.char_type;
                        eclass = ExprClass.Value;
@@ -338,34 +548,45 @@ namespace Mono.CSharp {
 
                public override DoubleConstant ConvertToDouble ()
                {
-                       return new DoubleConstant (Value);
+                       return new DoubleConstant (Value, loc);
                }
 
                public override FloatConstant ConvertToFloat ()
                {
-                       return new FloatConstant (Value);
+                       return new FloatConstant (Value, loc);
                }
 
                public override ULongConstant ConvertToULong ()
                {
-                       return new ULongConstant (Value);
+                       return new ULongConstant (Value, loc);
                }
 
                public override LongConstant ConvertToLong ()
                {
-                       return new LongConstant (Value);
+                       return new LongConstant (Value, loc);
                }
 
                public override UIntConstant ConvertToUInt ()
                {
-                       return new UIntConstant (Value);
+                       return new UIntConstant (Value, loc);
                }
 
                public override IntConstant ConvertToInt ()
                {
-                       return new IntConstant (Value);
+                       return new IntConstant (Value, loc);
+               }
+
+               public override Constant Increment ()
+               {
+                       return new CharConstant (checked ((char)(Value + 1)), loc);
                }
                
+               public override bool IsDefaultValue {
+                       get {
+                               return Value == 0;
+                       }
+               }
+
                public override bool IsNegative {
                        get {
                                return false;
@@ -375,12 +596,46 @@ namespace Mono.CSharp {
                public override bool IsZeroInteger {
                        get { return Value == '\0'; }
                }
+
+               public override Constant Reduce (EmitContext ec, Type target_type)
+               {
+                       if (target_type == TypeManager.byte_type) {
+                               CheckRange (ec, Value, target_type, Byte.MinValue, Byte.MaxValue);
+                               return new ByteConstant ((byte) Value, Location);
+                       }
+                       if (target_type == TypeManager.sbyte_type) {
+                               CheckRange (ec, Value, target_type, SByte.MinValue, SByte.MaxValue);
+                               return new SByteConstant ((sbyte) Value, Location);
+                       }
+                       if (target_type == TypeManager.short_type) {
+                               CheckRange (ec, Value, target_type, Int16.MinValue, Int16.MaxValue);
+                               return new ShortConstant ((short) Value, Location);
+                       }
+                       if (target_type == TypeManager.int32_type)
+                               return new IntConstant ((int) Value, Location);
+                       if (target_type == TypeManager.uint32_type)
+                               return new UIntConstant ((uint) Value, Location);
+                       if (target_type == TypeManager.int64_type)
+                               return new LongConstant ((long) Value, Location);
+                       if (target_type == TypeManager.uint64_type)
+                               return new ULongConstant ((ulong) Value, Location);
+                       if (target_type == TypeManager.float_type)
+                               return new FloatConstant ((float) Value, Location);
+                       if (target_type == TypeManager.double_type)
+                               return new DoubleConstant ((double) Value, Location);
+                       if (target_type == TypeManager.decimal_type)
+                               return new DecimalConstant ((decimal) Value, Location);
+
+                       return null;
+               }
+
        }
 
        public class SByteConstant : Constant {
                public readonly sbyte Value;
 
-               public SByteConstant (sbyte v)
+               public SByteConstant (sbyte v, Location loc):
+                       base (loc)
                {
                        type = TypeManager.sbyte_type;
                        eclass = ExprClass.Value;
@@ -404,25 +659,25 @@ namespace Mono.CSharp {
 
                public override DoubleConstant ConvertToDouble ()
                {
-                       return new DoubleConstant (Value);
+                       return new DoubleConstant (Value, loc);
                }
 
                public override FloatConstant ConvertToFloat ()
                {
-                       return new FloatConstant (Value);
+                       return new FloatConstant (Value, loc);
                }
 
                public override ULongConstant ConvertToULong ()
                {
                        if (Value >= 0)
-                               return new ULongConstant ((ulong) Value);
+                               return new ULongConstant ((ulong) Value, loc);
                        
                        return null;
                }
 
                public override LongConstant ConvertToLong ()
                {
-                       return new LongConstant (Value);
+                       return new LongConstant (Value, loc);
                }
 
                public override UIntConstant ConvertToUInt ()
@@ -432,9 +687,20 @@ namespace Mono.CSharp {
 
                public override IntConstant ConvertToInt ()
                {
-                       return new IntConstant (Value);
+                       return new IntConstant (Value, loc);
                }
                
+               public override Constant Increment ()
+               {
+                   return new SByteConstant (checked((sbyte)(Value + 1)), loc);
+               }
+
+               public override bool IsDefaultValue {
+                       get {
+                               return Value == 0;
+                       }
+               }
+
                public override bool IsNegative {
                        get {
                                return Value < 0;
@@ -444,12 +710,50 @@ namespace Mono.CSharp {
                public override bool IsZeroInteger {
                        get { return Value == 0; }
                }
+
+               public override Constant Reduce (EmitContext ec, Type target_type)
+               {
+                       if (target_type == TypeManager.byte_type) {
+                               CheckUnsigned (ec, Value, target_type);
+                               return new ByteConstant ((byte) Value, Location);
+                       }
+                       if (target_type == TypeManager.short_type)
+                               return new ShortConstant ((short) Value, Location);
+                       if (target_type == TypeManager.ushort_type) {
+                               CheckUnsigned (ec, Value, target_type);
+                               return new UShortConstant ((ushort) Value, Location);
+                       } if (target_type == TypeManager.int32_type)
+                                 return new IntConstant ((int) Value, Location);
+                       if (target_type == TypeManager.uint32_type) {
+                               CheckUnsigned (ec, Value, target_type);
+                               return new UIntConstant ((uint) Value, Location);
+                       } if (target_type == TypeManager.int64_type)
+                                 return new LongConstant ((long) Value, Location);
+                       if (target_type == TypeManager.uint64_type) {
+                               CheckUnsigned (ec, Value, target_type);
+                               return new ULongConstant ((ulong) Value, Location);
+                       }
+                       if (target_type == TypeManager.float_type)
+                               return new FloatConstant ((float) Value, Location);
+                       if (target_type == TypeManager.double_type)
+                               return new DoubleConstant ((double) Value, Location);
+                       if (target_type == TypeManager.char_type) {
+                               CheckUnsigned (ec, Value, target_type);
+                               return new CharConstant ((char) Value, Location);
+                       }
+                       if (target_type == TypeManager.decimal_type)
+                               return new DecimalConstant ((decimal) Value, Location);
+
+                       return null;
+               }
+
        }
 
        public class ShortConstant : Constant {
                public readonly short Value;
 
-               public ShortConstant (short v)
+               public ShortConstant (short v, Location loc):
+                       base (loc)
                {
                        type = TypeManager.short_type;
                        eclass = ExprClass.Value;
@@ -473,12 +777,12 @@ namespace Mono.CSharp {
 
                public override DoubleConstant ConvertToDouble ()
                {
-                       return new DoubleConstant (Value);
+                       return new DoubleConstant (Value, loc);
                }
 
                public override FloatConstant ConvertToFloat ()
                {
-                       return new FloatConstant (Value);
+                       return new FloatConstant (Value, loc);
                }
 
                public override ULongConstant ConvertToULong ()
@@ -488,7 +792,7 @@ namespace Mono.CSharp {
 
                public override LongConstant ConvertToLong ()
                {
-                       return new LongConstant (Value);
+                       return new LongConstant (Value, loc);
                }
 
                public override UIntConstant ConvertToUInt ()
@@ -498,7 +802,18 @@ namespace Mono.CSharp {
 
                public override IntConstant ConvertToInt ()
                {
-                       return new IntConstant (Value);
+                       return new IntConstant (Value, loc);
+               }
+
+               public override Constant Increment ()
+               {
+                       return new ShortConstant (checked((short)(Value + 1)), loc);
+               }
+
+               public override bool IsDefaultValue {
+                       get {
+                               return Value == 0;
+                       }
                }
                
                public override bool IsZeroInteger {
@@ -510,12 +825,54 @@ namespace Mono.CSharp {
                                return Value < 0;
                        }
                }
+
+               public override Constant Reduce (EmitContext ec, Type target_type)
+               {
+                       if (target_type == TypeManager.byte_type) {
+                               CheckRange (ec, Value, target_type, Byte.MinValue, Byte.MaxValue);
+                               return new ByteConstant ((byte) Value, Location);
+                       }
+                       if (target_type == TypeManager.sbyte_type) {
+                               CheckRange (ec, Value, target_type, SByte.MinValue, SByte.MaxValue);
+                               return new SByteConstant ((sbyte) Value, Location);
+                       }
+                       if (target_type == TypeManager.ushort_type) {
+                               CheckUnsigned (ec, Value, target_type);
+                               return new UShortConstant ((ushort) Value, Location);
+                       }
+                       if (target_type == TypeManager.int32_type)
+                               return new IntConstant ((int) Value, Location);
+                       if (target_type == TypeManager.uint32_type) {
+                               CheckUnsigned (ec, Value, target_type);
+                               return new UIntConstant ((uint) Value, Location);
+                       }
+                       if (target_type == TypeManager.int64_type)
+                               return new LongConstant ((long) Value, Location);
+                       if (target_type == TypeManager.uint64_type) {
+                               CheckUnsigned (ec, Value, target_type);
+                               return new ULongConstant ((ulong) Value, Location);
+                       }
+                       if (target_type == TypeManager.float_type)
+                               return new FloatConstant ((float) Value, Location);
+                       if (target_type == TypeManager.double_type)
+                               return new DoubleConstant ((double) Value, Location);
+                       if (target_type == TypeManager.char_type) {
+                               CheckRange (ec, Value, target_type, Char.MinValue, Char.MaxValue);
+                               return new CharConstant ((char) Value, Location);
+                       }
+                       if (target_type == TypeManager.decimal_type)
+                               return new DecimalConstant ((decimal) Value, Location);
+
+                       return null;
+               }
+
        }
 
        public class UShortConstant : Constant {
                public readonly ushort Value;
 
-               public UShortConstant (ushort v)
+               public UShortConstant (ushort v, Location loc):
+                       base (loc)
                {
                        type = TypeManager.ushort_type;
                        eclass = ExprClass.Value;
@@ -539,34 +896,45 @@ namespace Mono.CSharp {
 
                public override DoubleConstant ConvertToDouble ()
                {
-                       return new DoubleConstant (Value);
+                       return new DoubleConstant (Value, loc);
                }
 
                public override FloatConstant ConvertToFloat ()
                {
-                       return new FloatConstant (Value);
+                       return new FloatConstant (Value, loc);
                }
 
                public override ULongConstant ConvertToULong ()
                {
-                       return new ULongConstant (Value);
+                       return new ULongConstant (Value, loc);
                }
 
                public override LongConstant ConvertToLong ()
                {
-                       return new LongConstant (Value);
+                       return new LongConstant (Value, loc);
                }
 
                public override UIntConstant ConvertToUInt ()
                {
-                       return new UIntConstant (Value);
+                       return new UIntConstant (Value, loc);
                }
 
                public override IntConstant ConvertToInt ()
                {
-                       return new IntConstant (Value);
+                       return new IntConstant (Value, loc);
                }
                
+               public override Constant Increment ()
+               {
+                       return new UShortConstant (checked((ushort)(Value + 1)), loc);
+               }
+
+               public override bool IsDefaultValue {
+                       get {
+                               return Value == 0;
+                       }
+               }
+
                public override bool IsNegative {
                        get {
                                return false;
@@ -576,12 +944,49 @@ namespace Mono.CSharp {
                public override bool IsZeroInteger {
                        get { return Value == 0; }
                }
+
+               public override Constant Reduce (EmitContext ec, Type target_type)
+               {
+                       if (target_type == TypeManager.byte_type) {
+                               CheckRange (ec, Value, target_type, Byte.MinValue, Byte.MaxValue);
+                               return new ByteConstant ((byte) Value, Location);
+                       }
+                       if (target_type == TypeManager.sbyte_type) {
+                               CheckRange (ec, Value, target_type, SByte.MinValue, SByte.MaxValue);
+                               return new SByteConstant ((sbyte) Value, Location);
+                       }
+                       if (target_type == TypeManager.short_type) {
+                               CheckRange (ec, Value, target_type, Int16.MinValue, Int16.MaxValue);
+                               return new ShortConstant ((short) Value, Location);
+                       }
+                       if (target_type == TypeManager.int32_type)
+                               return new IntConstant ((int) Value, Location);
+                       if (target_type == TypeManager.uint32_type)
+                               return new UIntConstant ((uint) Value, Location);
+                       if (target_type == TypeManager.int64_type)
+                               return new LongConstant ((long) Value, Location);
+                       if (target_type == TypeManager.uint64_type)
+                               return new ULongConstant ((ulong) Value, Location);
+                       if (target_type == TypeManager.float_type)
+                               return new FloatConstant ((float) Value, Location);
+                       if (target_type == TypeManager.double_type)
+                               return new DoubleConstant ((double) Value, Location);
+                       if (target_type == TypeManager.char_type) {
+                               CheckRange (ec, Value, target_type, Char.MinValue, Char.MaxValue);
+                               return new CharConstant ((char) Value, Location);
+                       }
+                       if (target_type == TypeManager.decimal_type)
+                               return new DecimalConstant ((decimal) Value, Location);
+
+                       return null;
+               }
        }
 
        public class IntConstant : Constant {
                public readonly int Value;
 
-               public IntConstant (int v)
+               public IntConstant (int v, Location loc):
+                       base (loc)
                {
                        type = TypeManager.int32_type;
                        eclass = ExprClass.Value;
@@ -657,17 +1062,17 @@ namespace Mono.CSharp {
 
                public override DecimalConstant ConvertToDecimal()
                {
-                       return new DecimalConstant (Value);
+                       return new DecimalConstant (Value, loc);
                }
 
                public override DoubleConstant ConvertToDouble ()
                {
-                       return new DoubleConstant (Value);
+                       return new DoubleConstant (Value, loc);
                }
 
                public override FloatConstant ConvertToFloat ()
                {
-                       return new FloatConstant (Value);
+                       return new FloatConstant (Value, loc);
                }
 
                public override ULongConstant ConvertToULong ()
@@ -675,12 +1080,12 @@ namespace Mono.CSharp {
                        if (Value < 0)
                                return null;
 
-                       return new ULongConstant ((ulong) Value);
+                       return new ULongConstant ((ulong) Value, loc);
                }
 
                public override LongConstant ConvertToLong ()
                {
-                       return new LongConstant (Value);
+                       return new LongConstant (Value, loc);
                }
 
                public override UIntConstant ConvertToUInt ()
@@ -688,13 +1093,24 @@ namespace Mono.CSharp {
                        if (Value < 0)
                                return null;
 
-                       return new UIntConstant ((uint) Value);
+                       return new UIntConstant ((uint) Value, loc);
                }
 
                public override IntConstant ConvertToInt ()
                {
                        return this;
                }
+
+               public override Constant Increment ()
+               {
+                       return new IntConstant (checked(Value + 1), loc);
+               }
+
+               public override bool IsDefaultValue {
+                       get {
+                               return Value == 0;
+                       }
+               }
                
                public override bool IsNegative {
                        get {
@@ -705,12 +1121,55 @@ namespace Mono.CSharp {
                public override bool IsZeroInteger {
                        get { return Value == 0; }
                }
+
+               public override Constant Reduce (EmitContext ec, Type target_type)
+               {
+                       if (target_type == TypeManager.byte_type) {
+                               CheckRange (ec, Value, target_type, Byte.MinValue, Byte.MaxValue);
+                               return new ByteConstant ((byte) Value, Location);
+                       }
+                       if (target_type == TypeManager.sbyte_type) {
+                               CheckRange (ec, Value, target_type, SByte.MinValue, SByte.MaxValue);
+                               return new SByteConstant ((sbyte) Value, Location);
+                       }
+                       if (target_type == TypeManager.short_type) {
+                               CheckRange (ec, Value, target_type, Int16.MinValue, Int16.MaxValue);
+                               return new ShortConstant ((short) Value, Location);
+                       }
+                       if (target_type == TypeManager.ushort_type) {
+                               CheckRange (ec, Value, target_type, UInt16.MinValue, UInt16.MaxValue);
+                               return new UShortConstant ((ushort) Value, Location);
+                       }
+                       if (target_type == TypeManager.uint32_type) {
+                               CheckRange (ec, Value, target_type, Int32.MinValue, Int32.MaxValue);
+                               return new UIntConstant ((uint) Value, Location);
+                       }
+                       if (target_type == TypeManager.int64_type)
+                               return new LongConstant ((long) Value, Location);
+                       if (target_type == TypeManager.uint64_type) {
+                               CheckUnsigned (ec, Value, target_type);
+                               return new ULongConstant ((ulong) Value, Location);
+                       }
+                       if (target_type == TypeManager.float_type)
+                               return new FloatConstant ((float) Value, Location);
+                       if (target_type == TypeManager.double_type)
+                               return new DoubleConstant ((double) Value, Location);
+                       if (target_type == TypeManager.char_type) {
+                               CheckRange (ec, Value, target_type, Char.MinValue, Char.MaxValue);
+                               return new CharConstant ((char) Value, Location);
+                       }
+                       if (target_type == TypeManager.decimal_type)
+                               return new DecimalConstant ((decimal) Value, Location);
+
+                       return null;
+               }
        }
 
        public class UIntConstant : Constant {
                public readonly uint Value;
 
-               public UIntConstant (uint v)
+               public UIntConstant (uint v, Location loc):
+                       base (loc)
                {
                        type = TypeManager.uint32_type;
                        eclass = ExprClass.Value;
@@ -734,22 +1193,22 @@ namespace Mono.CSharp {
 
                public override DoubleConstant ConvertToDouble ()
                {
-                       return new DoubleConstant (Value);
+                       return new DoubleConstant (Value, loc);
                }
 
                public override FloatConstant ConvertToFloat ()
                {
-                       return new FloatConstant (Value);
+                       return new FloatConstant (Value, loc);
                }
 
                public override ULongConstant ConvertToULong ()
                {
-                       return new ULongConstant (Value);
+                       return new ULongConstant (Value, loc);
                }
 
                public override LongConstant ConvertToLong ()
                {
-                       return new LongConstant (Value);
+                       return new LongConstant (Value, loc);
                }
 
                public override UIntConstant ConvertToUInt ()
@@ -761,7 +1220,18 @@ namespace Mono.CSharp {
                {
                        return null;
                }
-               
+       
+               public override Constant Increment ()
+               {
+                       return new UIntConstant (checked(Value + 1), loc);
+               }
+       
+               public override bool IsDefaultValue {
+                       get {
+                               return Value == 0;
+                       }
+               }
+
                public override bool IsNegative {
                        get {
                                return false;
@@ -771,12 +1241,54 @@ namespace Mono.CSharp {
                public override bool IsZeroInteger {
                        get { return Value == 0; }
                }
+
+               public override Constant Reduce (EmitContext ec, Type target_type)
+               {
+                       if (target_type == TypeManager.byte_type) {
+                               CheckRange (ec, Value, target_type, Char.MinValue, Char.MaxValue);
+                               return new ByteConstant ((byte) Value, Location);
+                       }
+                       if (target_type == TypeManager.sbyte_type) {
+                               CheckRange (ec, Value, target_type, SByte.MinValue, SByte.MaxValue);
+                               return new SByteConstant ((sbyte) Value, Location);
+                       }
+                       if (target_type == TypeManager.short_type) {
+                               CheckRange (ec, Value, target_type, Int16.MinValue, Int16.MaxValue);
+                               return new ShortConstant ((short) Value, Location);
+                       }
+                       if (target_type == TypeManager.ushort_type) {
+                               CheckRange (ec, Value, target_type, UInt16.MinValue, UInt16.MaxValue);
+                               return new UShortConstant ((ushort) Value, Location);
+                       }
+                       if (target_type == TypeManager.int32_type) {
+                               CheckRange (ec, Value, target_type, Int32.MinValue, Int32.MaxValue);
+                               return new IntConstant ((int) Value, Location);
+                       }
+                       if (target_type == TypeManager.int64_type)
+                               return new LongConstant ((long) Value, Location);
+                       if (target_type == TypeManager.uint64_type)
+                               return new ULongConstant ((ulong) Value, Location);
+                       if (target_type == TypeManager.float_type)
+                               return new FloatConstant ((float) Value, Location);
+                       if (target_type == TypeManager.double_type)
+                               return new DoubleConstant ((double) Value, Location);
+                       if (target_type == TypeManager.char_type) {
+                               CheckRange (ec, Value, target_type, Char.MinValue, Char.MaxValue);
+                               return new CharConstant ((char) Value, Location);
+                       }
+                       if (target_type == TypeManager.decimal_type)
+                               return new DecimalConstant ((decimal) Value, Location);
+
+                       return null;
+               }
+
        }
 
        public class LongConstant : Constant {
                public readonly long Value;
 
-               public LongConstant (long v)
+               public LongConstant (long v, Location loc):
+                       base (loc)
                {
                        type = TypeManager.int64_type;
                        eclass = ExprClass.Value;
@@ -812,12 +1324,12 @@ namespace Mono.CSharp {
 
                public override DoubleConstant ConvertToDouble ()
                {
-                       return new DoubleConstant (Value);
+                       return new DoubleConstant (Value, loc);
                }
 
                public override FloatConstant ConvertToFloat ()
                {
-                       return new FloatConstant (Value);
+                       return new FloatConstant (Value, loc);
                }
 
                public override ULongConstant ConvertToULong ()
@@ -825,7 +1337,7 @@ namespace Mono.CSharp {
                        if (Value < 0)
                                return null;
                        
-                       return new ULongConstant ((ulong) Value);
+                       return new ULongConstant ((ulong) Value, loc);
                }
 
                public override LongConstant ConvertToLong ()
@@ -842,7 +1354,18 @@ namespace Mono.CSharp {
                {
                        return null;
                }
+
+               public override Constant Increment ()
+               {
+                       return new LongConstant (checked(Value + 1), loc);
+               }
                
+               public override bool IsDefaultValue {
+                       get {
+                               return Value == 0;
+                       }
+               }
+
                public override bool IsNegative {
                        get {
                                return Value < 0;
@@ -852,12 +1375,58 @@ namespace Mono.CSharp {
                public override bool IsZeroInteger {
                        get { return Value == 0; }
                }
+
+               public override Constant Reduce (EmitContext ec, Type target_type)
+               {
+                       if (target_type == TypeManager.byte_type) {
+                               CheckRange (ec, Value, target_type, Byte.MinValue, Byte.MaxValue);
+                               return new ByteConstant ((byte) Value, Location);
+                       }
+                       if (target_type == TypeManager.sbyte_type) {
+                               CheckRange (ec, Value, target_type, SByte.MinValue, SByte.MaxValue);
+                               return new SByteConstant ((sbyte) Value, Location);
+                       }
+                       if (target_type == TypeManager.short_type) {
+                               CheckRange (ec, Value, target_type, Int16.MinValue, Int16.MaxValue);
+                               return new ShortConstant ((short) Value, Location);
+                       }
+                       if (target_type == TypeManager.ushort_type) {
+                               CheckRange (ec, Value, target_type, UInt16.MinValue, UInt16.MaxValue);
+                               return new UShortConstant ((ushort) Value, Location);
+                       }
+                       if (target_type == TypeManager.int32_type) {
+                               CheckRange (ec, Value, target_type, Int32.MinValue, Int32.MaxValue);
+                               return new IntConstant ((int) Value, Location);
+                       }
+                       if (target_type == TypeManager.uint32_type) {
+                               CheckRange (ec, Value, target_type, UInt32.MinValue, UInt32.MaxValue);
+                               return new UIntConstant ((uint) Value, Location);
+                       }
+                       if (target_type == TypeManager.uint64_type) {
+                               CheckUnsigned (ec, Value, target_type);
+                               return new ULongConstant ((ulong) Value, Location);
+                       }
+                       if (target_type == TypeManager.float_type)
+                               return new FloatConstant ((float) Value, Location);
+                       if (target_type == TypeManager.double_type)
+                               return new DoubleConstant ((double) Value, Location);
+                       if (target_type == TypeManager.char_type) {
+                               CheckRange (ec, Value, target_type, Char.MinValue, Char.MaxValue);
+                               return new CharConstant ((char) Value, Location);
+                       }
+                       if (target_type == TypeManager.decimal_type)
+                               return new DecimalConstant ((decimal) Value, Location);
+
+                       return null;
+               }
+
        }
 
        public class ULongConstant : Constant {
                public readonly ulong Value;
 
-               public ULongConstant (ulong v)
+               public ULongConstant (ulong v, Location loc):
+                       base (loc)
                {
                        type = TypeManager.uint64_type;
                        eclass = ExprClass.Value;
@@ -883,12 +1452,12 @@ namespace Mono.CSharp {
 
                public override DoubleConstant ConvertToDouble ()
                {
-                       return new DoubleConstant (Value);
+                       return new DoubleConstant (Value, loc);
                }
 
                public override FloatConstant ConvertToFloat ()
                {
-                       return new FloatConstant (Value);
+                       return new FloatConstant (Value, loc);
                }
 
                public override ULongConstant ConvertToULong ()
@@ -911,6 +1480,17 @@ namespace Mono.CSharp {
                        return null;
                }
                
+               public override Constant Increment ()
+               {
+                       return new ULongConstant (checked(Value + 1), loc);
+               }
+
+               public override bool IsDefaultValue {
+                       get {
+                               return Value == 0;
+                       }
+               }
+
                public override bool IsNegative {
                        get {
                                return false;
@@ -920,12 +1500,58 @@ namespace Mono.CSharp {
                public override bool IsZeroInteger {
                        get { return Value == 0; }
                }
+
+               public override Constant Reduce (EmitContext ec, Type target_type)
+               {
+                       if (target_type == TypeManager.byte_type) {
+                               CheckRange (ec, Value, target_type, Byte.MaxValue);
+                               return new ByteConstant ((byte) Value, Location);
+                       }
+                       if (target_type == TypeManager.sbyte_type) {
+                               CheckRange (ec, Value, target_type, (ulong) SByte.MaxValue);
+                               return new SByteConstant ((sbyte) Value, Location);
+                       }
+                       if (target_type == TypeManager.short_type) {
+                               CheckRange (ec, Value, target_type, (ulong) Int16.MaxValue);
+                               return new ShortConstant ((short) Value, Location);
+                       }
+                       if (target_type == TypeManager.ushort_type) {
+                               CheckRange (ec, Value, target_type, UInt16.MaxValue);
+                               return new UShortConstant ((ushort) Value, Location);
+                       }
+                       if (target_type == TypeManager.int32_type) {
+                               CheckRange (ec, Value, target_type, Int32.MaxValue);
+                               return new IntConstant ((int) Value, Location);
+                       }
+                       if (target_type == TypeManager.uint32_type) {
+                               CheckRange (ec, Value, target_type, UInt32.MaxValue);
+                               return new UIntConstant ((uint) Value, Location);
+                       }
+                       if (target_type == TypeManager.int64_type) {
+                               CheckRange (ec, Value, target_type, (ulong) Int64.MaxValue);
+                               return new LongConstant ((long) Value, Location);
+                       }
+                       if (target_type == TypeManager.float_type)
+                               return new FloatConstant ((float) Value, Location);
+                       if (target_type == TypeManager.double_type)
+                               return new DoubleConstant ((double) Value, Location);
+                       if (target_type == TypeManager.char_type) {
+                               CheckRange (ec, Value, target_type, Char.MaxValue);
+                               return new CharConstant ((char) Value, Location);
+                       }
+                       if (target_type == TypeManager.decimal_type)
+                               return new DecimalConstant ((decimal) Value, Location);
+
+                       return null;
+               }
+
        }
 
        public class FloatConstant : Constant {
                public readonly float Value;
 
-               public FloatConstant (float v)
+               public FloatConstant (float v, Location loc):
+                       base (loc)
                {
                        type = TypeManager.float_type;
                        eclass = ExprClass.Value;
@@ -949,7 +1575,7 @@ namespace Mono.CSharp {
 
                public override DoubleConstant ConvertToDouble ()
                {
-                       return new DoubleConstant (Value);
+                       return new DoubleConstant (Value, loc);
                }
 
                public override FloatConstant ConvertToFloat ()
@@ -972,17 +1598,58 @@ namespace Mono.CSharp {
                        return null;
                }
 
+               public override Constant Increment ()
+               {
+                       return new FloatConstant (checked(Value + 1), loc);
+               }
+
+               public override bool IsDefaultValue {
+                       get {
+                               return Value == 0;
+                       }
+               }
+
                public override bool IsNegative {
                        get {
                                return Value < 0;
                        }
                }
+
+               public override Constant Reduce (EmitContext ec, Type target_type)
+               {
+                       if (target_type == TypeManager.byte_type)
+                               return new ByteConstant ((byte) Value, Location);
+                       if (target_type == TypeManager.sbyte_type)
+                               return new SByteConstant ((sbyte) Value, Location);
+                       if (target_type == TypeManager.short_type)
+                               return new ShortConstant ((short) Value, Location);
+                       if (target_type == TypeManager.ushort_type)
+                               return new UShortConstant ((ushort) Value, Location);
+                       if (target_type == TypeManager.int32_type)
+                               return new IntConstant ((int) Value, Location);
+                       if (target_type == TypeManager.uint32_type)
+                               return new UIntConstant ((uint) Value, Location);
+                       if (target_type == TypeManager.int64_type)
+                               return new LongConstant ((long) Value, Location);
+                       if (target_type == TypeManager.uint64_type)
+                               return new ULongConstant ((ulong) Value, Location);
+                       if (target_type == TypeManager.double_type)
+                               return new DoubleConstant ((double) Value, Location);
+                       if (target_type == TypeManager.char_type)
+                               return new CharConstant ((char) Value, Location);
+                       if (target_type == TypeManager.decimal_type)
+                               return new DecimalConstant ((decimal) Value, Location);
+
+                       return null;
+               }
+
        }
 
        public class DoubleConstant : Constant {
                public readonly double Value;
 
-               public DoubleConstant (double v)
+               public DoubleConstant (double v, Location loc):
+                       base (loc)
                {
                        type = TypeManager.double_type;
                        eclass = ExprClass.Value;
@@ -1034,17 +1701,64 @@ namespace Mono.CSharp {
                        return null;
                }
 
+               public override Constant Increment ()
+               {
+                       return new DoubleConstant (checked(Value + 1), loc);
+               }
+
+               public override bool IsDefaultValue {
+                       get {
+                               return Value == 0;
+                       }
+               }
+
                public override bool IsNegative {
                        get {
                                return Value < 0;
                        }
                }
+
+               public override Constant Reduce (EmitContext ec, Type target_type)
+               {
+                       if (target_type == TypeManager.byte_type) {
+                               CheckRange (ec, Value, target_type, Byte.MinValue, Byte.MaxValue);
+                               return new ByteConstant ((byte) Value, Location);
+                       }
+                       if (target_type == TypeManager.sbyte_type) {
+                               CheckRange (ec, Value, target_type, SByte.MinValue, SByte.MaxValue);
+                               return new SByteConstant ((sbyte) Value, Location);
+                       }
+                       if (target_type == TypeManager.short_type)
+                               return new ShortConstant ((short) Value, Location);
+                       if (target_type == TypeManager.ushort_type)
+                               return new UShortConstant ((ushort) Value, Location);
+                       if (target_type == TypeManager.int32_type)
+                               return new IntConstant ((int) Value, Location);
+                       if (target_type == TypeManager.uint32_type)
+                               return new UIntConstant ((uint) Value, Location);
+                       if (target_type == TypeManager.int64_type)
+                               return new LongConstant ((long) Value, Location);
+                       if (target_type == TypeManager.uint64_type)
+                               return new ULongConstant ((ulong) Value, Location);
+                       if (target_type == TypeManager.float_type)
+                               return new FloatConstant ((float) Value, Location);
+                       if (target_type == TypeManager.char_type) {
+                               CheckRange (ec, Value, target_type, char.MinValue, char.MaxValue);
+                               return new CharConstant ((char) Value, Location);
+                       }
+                       if (target_type == TypeManager.decimal_type)
+                               return new DecimalConstant ((decimal) Value, Location);
+
+                       return null;
+               }
+
        }
 
        public class DecimalConstant : Constant {
                public readonly decimal Value;
 
-               public DecimalConstant (decimal d)
+               public DecimalConstant (decimal d, Location loc):
+                       base (loc)
                {
                        type = TypeManager.decimal_type;
                        eclass = ExprClass.Value;
@@ -1094,17 +1808,58 @@ namespace Mono.CSharp {
                        ig.Emit (OpCodes.Newobj, TypeManager.void_decimal_ctor_five_args);
                }
 
+               public override Constant Increment ()
+               {
+                       return new DecimalConstant (checked (Value + 1), loc);
+               }
+
+               public override bool IsDefaultValue {
+                       get {
+                               return Value == 0;
+                       }
+               }
+
                public override bool IsNegative {
                        get {
                                return Value < 0;
                        }
                }
+
+               public override Constant Reduce (EmitContext ec, Type target_type)
+               {
+                       if (target_type == TypeManager.sbyte_type)
+                               return new SByteConstant ((sbyte)Value, loc);
+                       if (target_type == TypeManager.byte_type)
+                               return new ByteConstant ((byte)Value, loc);
+                       if (target_type == TypeManager.short_type)
+                               return new ShortConstant ((short)Value, loc);
+                       if (target_type == TypeManager.ushort_type)
+                               return new UShortConstant ((ushort)Value, loc);
+                       if (target_type == TypeManager.int32_type)
+                               return new IntConstant ((int)Value, loc);
+                       if (target_type == TypeManager.uint32_type)
+                               return new UIntConstant ((uint)Value, loc);
+                       if (target_type == TypeManager.int64_type)
+                               return new LongConstant ((long)Value, loc);
+                       if (target_type == TypeManager.uint64_type)
+                               return new ULongConstant ((ulong)Value, loc);
+                       if (target_type == TypeManager.char_type)
+                               return new CharConstant ((char)Value, loc);
+                       if (target_type == TypeManager.float_type)
+                               return new FloatConstant ((float)Value, loc);
+                       if (target_type == TypeManager.double_type)
+                               return new DoubleConstant ((double)Value, loc);
+
+                       return null;
+               }
+
        }
 
        public class StringConstant : Constant {
                public readonly string Value;
 
-               public StringConstant (string s)
+               public StringConstant (string s, Location loc):
+                       base (loc)
                {
                        type = TypeManager.string_type;
                        eclass = ExprClass.Value;
@@ -1130,11 +1885,27 @@ namespace Mono.CSharp {
                                ec.ig.Emit (OpCodes.Ldstr, Value);
                }
 
+               public override Constant Increment ()
+               {
+                       throw new NotSupportedException ();
+               }
+
+               public override bool IsDefaultValue {
+                       get {
+                               return Value == null;
+                       }
+               }
+
                public override bool IsNegative {
                        get {
                                return false;
                        }
                }
+
+               public override Constant Reduce (EmitContext ec, Type target_type)
+               {
+                       return null;
+               }
        }
 
 }