//
-// constant.cs: Constant expressions and constant folding.
+// constant.cs: Constants.
//
// Author:
// Miguel de Icaza (miguel@ximian.com)
namespace Mono.CSharp {
using System;
- using System.Reflection;
using System.Reflection.Emit;
- using System.Collections;
+ /// <summary>
+ /// Base class for constants and literals.
+ /// </summary>
+ public abstract class Constant : Expression {
+ /// <remarks>
+ /// This is different from ToString in that ToString
+ /// is supposed to be there for debugging purposes,
+ /// and is not guaranteed to be useful for anything else,
+ /// AsString() will provide something that can be used
+ /// for round-tripping C# code. Maybe it can be used
+ /// for IL assembly as well.
+ /// </remarks>
+ public abstract string AsString ();
- public class Constant : Expression {
+ override public string ToString ()
+ {
+ return this.GetType ().Name + " (" + AsString () + ")";
+ }
+
+ /// <summary>
+ /// This is used to obtain the actual value of the literal
+ /// cast into an object.
+ /// </summary>
+ public abstract object GetValue ();
+
+ /// <summary>
+ /// Constants are always born in a fully resolved state
+ /// </summary>
+ public override Expression DoResolve (EmitContext ec)
+ {
+ return this;
+ }
+
+ //
+ // The various ToXXXX conversion functions are used by the constant
+ // folding evaluator. A null value is returned if the conversion is
+ // not possible.
+ //
+ // Note: not all the patterns for catching `implicit_conv' are the same.
+ // some implicit conversions can never be performed between two types
+ // even if the conversion would be lossless (for example short to uint),
+ // but some conversions are explicitly permitted by the standard provided
+ // that there will be no loss of information (for example, int to uint).
+ //
+ public DoubleConstant ToDouble (Location loc)
+ {
+ DoubleConstant c = ConvertToDouble ();
+
+ if (c == null)
+ Error_CannotConvertImplicit (loc, Type, TypeManager.double_type);
+
+ return c;
+ }
+
+ public FloatConstant ToFloat (Location loc)
+ {
+ FloatConstant c = ConvertToFloat ();
+
+ if (c == null)
+ Error_CannotConvertImplicit (loc, Type, TypeManager.float_type);
+
+ return c;
+ }
+
+ public ULongConstant ToULong (Location loc)
+ {
+ ULongConstant c = ConvertToULong ();
+
+ if (c == null)
+ Error_CannotConvertImplicit (loc, Type, TypeManager.uint64_type);
+
+ return c;
+ }
+
+ public LongConstant ToLong (Location loc)
+ {
+ LongConstant c = ConvertToLong ();
+
+ if (c == null)
+ Error_CannotConvertImplicit (loc, Type, TypeManager.int64_type);
+
+ return c;
+ }
+
+ public UIntConstant ToUInt (Location loc)
+ {
+ UIntConstant c = ConvertToUInt ();
+
+ if (c == null)
+ Error_CannotConvertImplicit (loc, Type, TypeManager.uint32_type);
+
+ return c;
+ }
+
+ public IntConstant ToInt (Location loc)
+ {
+ IntConstant c = ConvertToInt ();
+
+ if (c == null)
+ Error_CannotConvertImplicit (loc, Type, TypeManager.int32_type);
+
+ return c;
+ }
+
+ public virtual DoubleConstant ConvertToDouble ()
+ {
+ return null;
+ }
+
+ public virtual FloatConstant ConvertToFloat ()
+ {
+ return null;
+ }
+
+ public virtual ULongConstant ConvertToULong ()
+ {
+ return null;
+ }
+
+ public virtual LongConstant ConvertToLong ()
+ {
+ return null;
+ }
+
+ public virtual UIntConstant ConvertToUInt ()
+ {
+ return null;
+ }
+
+ public virtual IntConstant ConvertToInt ()
+ {
+ return null;
+ }
+ }
+
+ public class BoolConstant : Constant {
+ public readonly bool Value;
+
+ public BoolConstant (bool val)
+ {
+ type = TypeManager.bool_type;
+ eclass = ExprClass.Value;
- public readonly string Name;
- public Expression Expr;
- public readonly string ConstantType;
- public Attributes OptAttributes;
+ Value = val;
+ }
+
+ override public string AsString ()
+ {
+ return Value ? "true" : "false";
+ }
+
+ public override object GetValue ()
+ {
+ return (object) Value;
+ }
+
- int mod_flags;
+ public override void Emit (EmitContext ec)
+ {
+ if (Value)
+ ec.ig.Emit (OpCodes.Ldc_I4_1);
+ else
+ ec.ig.Emit (OpCodes.Ldc_I4_0);
+ }
+ }
- Location Location;
- FieldBuilder FieldBuilder;
+ public class ByteConstant : Constant {
+ public readonly byte Value;
- public const int AllowedModifiers =
- Modifiers.NEW |
- Modifiers.PUBLIC |
- Modifiers.PROTECTED |
- Modifiers.INTERNAL |
- Modifiers.PRIVATE;
+ public ByteConstant (byte v)
+ {
+ type = TypeManager.byte_type;
+ eclass = ExprClass.Value;
+ Value = v;
+ }
+
+ public override void Emit (EmitContext ec)
+ {
+ IntLiteral.EmitInt (ec.ig, Value);
+ }
+
+ public override string AsString ()
+ {
+ return Value.ToString ();
+ }
+
+ public override object GetValue ()
+ {
+ return Value;
+ }
+
+ public override DoubleConstant ConvertToDouble ()
+ {
+ return new DoubleConstant (Value);
+ }
- public Constant (string constant_type, string name, Expression expr, int mod_flags,
- Attributes attrs, Location loc)
+ public override FloatConstant ConvertToFloat ()
{
- this.ConstantType = constant_type;
- this.Name = name;
- this.Expr = expr;
- this.mod_flags = Modifiers.Check (AllowedModifiers, mod_flags, Modifiers.PRIVATE);
- this.Location = loc;
- OptAttributes = attrs;
+ return new FloatConstant (Value);
}
- public FieldAttributes FieldAttr {
- get {
- return FieldAttributes.Literal | FieldAttributes.Static |
- Modifiers.FieldAttr (mod_flags) ;
+ public override ULongConstant ConvertToULong ()
+ {
+ return new ULongConstant (Value);
+ }
+
+ public override LongConstant ConvertToLong ()
+ {
+ return new LongConstant (Value);
+ }
+
+ public override UIntConstant ConvertToUInt ()
+ {
+ return new UIntConstant (Value);
+ }
+
+ public override IntConstant ConvertToInt ()
+ {
+ return new IntConstant (Value);
+ }
+ }
+
+ public class CharConstant : Constant {
+ public readonly char Value;
+
+ public CharConstant (char v)
+ {
+ type = TypeManager.char_type;
+ eclass = ExprClass.Value;
+ Value = v;
+ }
+
+ public override void Emit (EmitContext ec)
+ {
+ IntLiteral.EmitInt (ec.ig, Value);
+ }
+
+ static public string descape (char c)
+ {
+ switch (c){
+ case '\a':
+ return "\\a";
+ case '\b':
+ return "\\b";
+ case '\n':
+ return "\\n";
+ case '\t':
+ return "\\t";
+ case '\v':
+ return "\\v";
+ case '\r':
+ return "\\r";
+ case '\\':
+ return "\\\\";
+ case '\f':
+ return "\\f";
+ case '\0':
+ return "\\0";
+ case '"':
+ return "\\\"";
+ case '\'':
+ return "\\\'";
}
+ return c.ToString ();
+ }
+
+ public override string AsString ()
+ {
+ return "\"" + descape (Value) + "\"";
+ }
+
+ public override object GetValue ()
+ {
+ return Value;
+ }
+
+ public override DoubleConstant ConvertToDouble ()
+ {
+ return new DoubleConstant (Value);
+ }
+
+ public override FloatConstant ConvertToFloat ()
+ {
+ return new FloatConstant (Value);
+ }
+
+ public override ULongConstant ConvertToULong ()
+ {
+ return new ULongConstant (Value);
+ }
+
+ public override LongConstant ConvertToLong ()
+ {
+ return new LongConstant (Value);
+ }
+
+ public override UIntConstant ConvertToUInt ()
+ {
+ return new UIntConstant (Value);
+ }
+
+ public override IntConstant ConvertToInt ()
+ {
+ return new IntConstant (Value);
+ }
+ }
+
+ public class SByteConstant : Constant {
+ public readonly sbyte Value;
+
+ public SByteConstant (sbyte v)
+ {
+ type = TypeManager.sbyte_type;
+ eclass = ExprClass.Value;
+ Value = v;
+ }
+
+ public override void Emit (EmitContext ec)
+ {
+ IntLiteral.EmitInt (ec.ig, Value);
+ }
+
+ public override string AsString ()
+ {
+ return Value.ToString ();
+ }
+
+ public override object GetValue ()
+ {
+ return Value;
+ }
+
+ public override DoubleConstant ConvertToDouble ()
+ {
+ return new DoubleConstant (Value);
+ }
+
+ public override FloatConstant ConvertToFloat ()
+ {
+ return new FloatConstant (Value);
+ }
+
+ public override ULongConstant ConvertToULong ()
+ {
+ if (Value >= 0)
+ return new ULongConstant ((ulong) Value);
+
+ return null;
+ }
+
+ public override LongConstant ConvertToLong ()
+ {
+ return new LongConstant (Value);
+ }
+
+ public override UIntConstant ConvertToUInt ()
+ {
+ return null;
+ }
+
+ public override IntConstant ConvertToInt ()
+ {
+ return new IntConstant (Value);
+ }
+ }
+
+ public class ShortConstant : Constant {
+ public readonly short Value;
+
+ public ShortConstant (short v)
+ {
+ type = TypeManager.short_type;
+ eclass = ExprClass.Value;
+ Value = v;
+ }
+
+ public override void Emit (EmitContext ec)
+ {
+ IntLiteral.EmitInt (ec.ig, Value);
+ }
+
+ public override string AsString ()
+ {
+ return Value.ToString ();
+ }
+
+ public override object GetValue ()
+ {
+ return Value;
+ }
+
+ public override DoubleConstant ConvertToDouble ()
+ {
+ return new DoubleConstant (Value);
+ }
+
+ public override FloatConstant ConvertToFloat ()
+ {
+ return new FloatConstant (Value);
+ }
+
+ public override ULongConstant ConvertToULong ()
+ {
+ return null;
+ }
+
+ public override LongConstant ConvertToLong ()
+ {
+ return new LongConstant (Value);
+ }
+
+ public override UIntConstant ConvertToUInt ()
+ {
+ return null;
+ }
+
+ public override IntConstant ConvertToInt ()
+ {
+ return new IntConstant (Value);
+ }
+ }
+
+ public class UShortConstant : Constant {
+ public readonly ushort Value;
+
+ public UShortConstant (ushort v)
+ {
+ type = TypeManager.ushort_type;
+ eclass = ExprClass.Value;
+ Value = v;
}
- public int ModFlags {
- get {
- return mod_flags;
+ public override void Emit (EmitContext ec)
+ {
+ IntLiteral.EmitInt (ec.ig, Value);
+ }
+
+ public override string AsString ()
+ {
+ return Value.ToString ();
+ }
+
+ public override object GetValue ()
+ {
+ return Value;
+ }
+
+ public override DoubleConstant ConvertToDouble ()
+ {
+ return new DoubleConstant (Value);
+ }
+
+ public override FloatConstant ConvertToFloat ()
+ {
+ return new FloatConstant (Value);
+ }
+
+ public override ULongConstant ConvertToULong ()
+ {
+ return new ULongConstant (Value);
+ }
+
+ public override LongConstant ConvertToLong ()
+ {
+ return new LongConstant (Value);
+ }
+
+ public override UIntConstant ConvertToUInt ()
+ {
+ return new UIntConstant (Value);
+ }
+
+ public override IntConstant ConvertToInt ()
+ {
+ return new IntConstant (Value);
+ }
+ }
+
+ public class IntConstant : Constant {
+ public readonly int Value;
+
+ public IntConstant (int v)
+ {
+ type = TypeManager.int32_type;
+ eclass = ExprClass.Value;
+ Value = v;
+ }
+
+ static public void EmitInt (ILGenerator ig, int i)
+ {
+ switch (i){
+ case -1:
+ ig.Emit (OpCodes.Ldc_I4_M1);
+ break;
+
+ case 0:
+ ig.Emit (OpCodes.Ldc_I4_0);
+ break;
+
+ case 1:
+ ig.Emit (OpCodes.Ldc_I4_1);
+ break;
+
+ case 2:
+ ig.Emit (OpCodes.Ldc_I4_2);
+ break;
+
+ case 3:
+ ig.Emit (OpCodes.Ldc_I4_3);
+ break;
+
+ case 4:
+ ig.Emit (OpCodes.Ldc_I4_4);
+ break;
+
+ case 5:
+ ig.Emit (OpCodes.Ldc_I4_5);
+ break;
+
+ case 6:
+ ig.Emit (OpCodes.Ldc_I4_6);
+ break;
+
+ case 7:
+ ig.Emit (OpCodes.Ldc_I4_7);
+ break;
+
+ 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;
}
}
- public override Expression DoResolve (EmitContext ec)
+ public override void Emit (EmitContext ec)
+ {
+ EmitInt (ec.ig, Value);
+ }
+
+ public override string AsString ()
+ {
+ return Value.ToString ();
+ }
+
+ public override object GetValue ()
+ {
+ return Value;
+ }
+
+ public override DoubleConstant ConvertToDouble ()
+ {
+ return new DoubleConstant (Value);
+ }
+
+ public override FloatConstant ConvertToFloat ()
+ {
+ return new FloatConstant (Value);
+ }
+
+ public override ULongConstant ConvertToULong ()
+ {
+ if (Value < 0)
+ return null;
+
+ return new ULongConstant ((ulong) Value);
+ }
+
+ public override LongConstant ConvertToLong ()
+ {
+ return new LongConstant (Value);
+ }
+
+ public override UIntConstant ConvertToUInt ()
+ {
+ if (Value < 0)
+ return null;
+
+ return new UIntConstant ((uint) Value);
+ }
+
+ public override IntConstant ConvertToInt ()
{
- // FIXME: implement
return this;
}
+ }
+
+ public class UIntConstant : Constant {
+ public readonly uint Value;
+
+ public UIntConstant (uint v)
+ {
+ type = TypeManager.uint32_type;
+ eclass = ExprClass.Value;
+ Value = v;
+ }
public override void Emit (EmitContext ec)
{
- throw new Exception ("Unimplemented");
+ IntLiteral.EmitInt (ec.ig, unchecked ((int) Value));
}
-
- /// <summary>
- /// Defines the constant in the @parent
- /// </summary>
- public void Define (TypeContainer parent)
+
+ public override string AsString ()
{
- type = parent.LookupType (ConstantType, true);
+ return Value.ToString ();
+ }
- if (type == null)
- return;
-
- if (!TypeManager.IsBuiltinType (type) && (!type.IsSubclassOf (TypeManager.enum_type))) {
- Report.Error (-3, "Constant type is not valid (only system types are allowed)");
- return;
+ public override object GetValue ()
+ {
+ return Value;
+ }
+
+ public override DoubleConstant ConvertToDouble ()
+ {
+ return new DoubleConstant (Value);
+ }
+
+ public override FloatConstant ConvertToFloat ()
+ {
+ return new FloatConstant (Value);
+ }
+
+ public override ULongConstant ConvertToULong ()
+ {
+ return new ULongConstant (Value);
+ }
+
+ public override LongConstant ConvertToLong ()
+ {
+ return new LongConstant (Value);
+ }
+
+ public override UIntConstant ConvertToUInt ()
+ {
+ return this;
+ }
+
+ public override IntConstant ConvertToInt ()
+ {
+ return null;
+ }
+ }
+
+ public class LongConstant : Constant {
+ public readonly long Value;
+
+ public LongConstant (long v)
+ {
+ type = TypeManager.int64_type;
+ eclass = ExprClass.Value;
+ Value = v;
+ }
+
+ public override void Emit (EmitContext ec)
+ {
+ ILGenerator ig = ec.ig;
+
+ EmitLong (ig, Value);
+ }
+
+ static public void EmitLong (ILGenerator ig, long l)
+ {
+ if ((l >> 32) == 0){
+ IntLiteral.EmitInt (ig, unchecked ((int) l));
+ ig.Emit (OpCodes.Conv_U8);
+ } else {
+ ig.Emit (OpCodes.Ldc_I8, l);
}
-
- FieldBuilder = parent.TypeBuilder.DefineField (Name, type, FieldAttr);
-
}
- /// <summary>
- /// Emits the field value by evaluating the expression
- /// </summary>
- public void EmitConstant (TypeContainer parent)
+ public override string AsString ()
{
- if (FieldBuilder == null)
- return;
+ return Value.ToString ();
+ }
+
+ public override object GetValue ()
+ {
+ return Value;
+ }
+
+ public override DoubleConstant ConvertToDouble ()
+ {
+ return new DoubleConstant (Value);
+ }
+
+ public override FloatConstant ConvertToFloat ()
+ {
+ return new FloatConstant (Value);
+ }
+
+ public override ULongConstant ConvertToULong ()
+ {
+ if (Value < 0)
+ return null;
- EmitContext ec = new EmitContext (parent, null, type, ModFlags);
+ return new ULongConstant ((ulong) Value);
+ }
- Expr = Expression.Reduce (ec, Expr);
+ public override LongConstant ConvertToLong ()
+ {
+ return this;
+ }
- if (!(Expr is Literal)) {
- Report.Error (150, Location, "A constant value is expected");
- return;
- }
+ public override UIntConstant ConvertToUInt ()
+ {
+ return null;
+ }
- object val = ((Literal) Expr).GetValue ();
+ public override IntConstant ConvertToInt ()
+ {
+ return null;
+ }
+ }
- FieldBuilder.SetConstant (val);
+ public class ULongConstant : Constant {
+ public readonly ulong Value;
- TypeManager.RegisterField (FieldBuilder, val);
+ public ULongConstant (ulong v)
+ {
+ type = TypeManager.uint64_type;
+ eclass = ExprClass.Value;
+ Value = v;
+ }
+
+ public override void Emit (EmitContext ec)
+ {
+ ILGenerator ig = ec.ig;
+
+ LongLiteral.EmitLong (ig, unchecked ((long) Value));
+ }
+
+ public override string AsString ()
+ {
+ return Value.ToString ();
+ }
+
+ public override object GetValue ()
+ {
+ return Value;
+ }
+
+ public override DoubleConstant ConvertToDouble ()
+ {
+ return new DoubleConstant (Value);
+ }
+
+ public override FloatConstant ConvertToFloat ()
+ {
+ return new FloatConstant (Value);
+ }
+
+ public override ULongConstant ConvertToULong ()
+ {
+ return this;
+ }
+
+ public override LongConstant ConvertToLong ()
+ {
+ return null;
+ }
+
+ public override UIntConstant ConvertToUInt ()
+ {
+ return null;
+ }
+
+ public override IntConstant ConvertToInt ()
+ {
+ return null;
+ }
+ }
+
+ public class FloatConstant : Constant {
+ public readonly float Value;
+
+ public FloatConstant (float v)
+ {
+ type = TypeManager.float_type;
+ eclass = ExprClass.Value;
+ Value = v;
+ }
+
+ public override void Emit (EmitContext ec)
+ {
+ ec.ig.Emit (OpCodes.Ldc_R4, Value);
+ }
+
+ public override string AsString ()
+ {
+ return Value.ToString ();
+ }
+
+ public override object GetValue ()
+ {
+ return Value;
+ }
+
+ public override DoubleConstant ConvertToDouble ()
+ {
+ return new DoubleConstant (Value);
+ }
+
+ public override FloatConstant ConvertToFloat ()
+ {
+ return this;
+ }
+
+ public override LongConstant ConvertToLong ()
+ {
+ return null;
+ }
+
+ public override UIntConstant ConvertToUInt ()
+ {
+ return null;
+ }
+
+ public override IntConstant ConvertToInt ()
+ {
+ return null;
+ }
+ }
+
+ public class DoubleConstant : Constant {
+ public readonly double Value;
+
+ public DoubleConstant (double v)
+ {
+ type = TypeManager.double_type;
+ eclass = ExprClass.Value;
+ Value = v;
+ }
+
+ public override void Emit (EmitContext ec)
+ {
+ ec.ig.Emit (OpCodes.Ldc_R8, Value);
+ }
+
+ public override string AsString ()
+ {
+ return Value.ToString ();
+ }
+
+ public override object GetValue ()
+ {
+ return Value;
+ }
+
+ public override DoubleConstant ConvertToDouble ()
+ {
+ return this;
+ }
+
+ public override FloatConstant ConvertToFloat ()
+ {
+ return null;
+ }
+
+ public override ULongConstant ConvertToULong ()
+ {
+ return null;
+ }
+
+ public override LongConstant ConvertToLong ()
+ {
+ return null;
+ }
+
+ public override UIntConstant ConvertToUInt ()
+ {
+ return null;
+ }
+
+ public override IntConstant ConvertToInt ()
+ {
+ return null;
+ }
+ }
+
+ public class DecimalConstant : Constant {
+ public readonly decimal Value;
+
+ public DecimalConstant (decimal d)
+ {
+ type = TypeManager.decimal_type;
+ eclass = ExprClass.Value;
+ Value = d;
+ }
+
+ override public string AsString ()
+ {
+ return Value.ToString ();
+ }
+
+ public override object GetValue ()
+ {
+ return (object) Value;
+ }
+
+ public override void Emit (EmitContext ec)
+ {
+ int [] words = Decimal.GetBits (Value);
- return;
+ //
+ // FIXME: we could optimize this, and call a better
+ // constructor
+ //
+
+ ILGenerator ig = ec.ig;
+
+ IntConstant.EmitInt (ig, words [0]);
+ IntConstant.EmitInt (ig, words [1]);
+ IntConstant.EmitInt (ig, words [2]);
+
+ // sign
+ IntConstant.EmitInt (ig, words [3] >> 31);
+
+ // power
+ IntConstant.EmitInt (ig, (words [3] >> 16) & 0xff);
+
+ ig.Emit (OpCodes.Newobj, TypeManager.void_decimal_ctor_five_args);
}
}
+
+ public class StringConstant : Constant {
+ public readonly string Value;
+
+ public StringConstant (string s)
+ {
+ type = TypeManager.string_type;
+ eclass = ExprClass.Value;
+ Value = s;
+ }
+
+ // FIXME: Escape the string.
+ override public string AsString ()
+ {
+ return "\"" + Value + "\"";
+ }
+
+ public override object GetValue ()
+ {
+ return Value;
+ }
+
+ public override void Emit (EmitContext ec)
+ {
+ ec.ig.Emit (OpCodes.Ldstr, Value);
+ }
+ }
+
}
projects / mono.git / blobdiff