internal LocalBuilder GetLocal(Type type)
{
Debug.Assert(type != null);
LocalBuilder local;
if (_freeLocals.TryDequeue(type, out local))
{
Debug.Assert(type == local.LocalType);
return(local);
}
return(_ilg.DeclareLocal(type));
}
private void EnsureLabelAndValue()
{
if (!_labelDefined)
{
_labelDefined = true;
_label = _ilg.DefineLabel();
if (_node != null && _node.Type != typeof(void))
{
_value = _ilg.DeclareLocal(_node.Type);
}
}
}
private static void EmitNullableToNullableConversion(this ILGenerator il, Type typeFrom, Type typeTo, bool isChecked)
{
Debug.Assert(TypeUtils.IsNullableType(typeFrom));
Debug.Assert(TypeUtils.IsNullableType(typeTo));
Label labIfNull = default(Label);
Label labEnd = default(Label);
LocalBuilder locFrom = null;
LocalBuilder locTo = null;
locFrom = il.DeclareLocal(typeFrom);
il.Emit(OpCodes.Stloc, locFrom);
locTo = il.DeclareLocal(typeTo);
// test for null
il.Emit(OpCodes.Ldloca, locFrom);
il.EmitHasValue(typeFrom);
labIfNull = il.DefineLabel();
il.Emit(OpCodes.Brfalse_S, labIfNull);
il.Emit(OpCodes.Ldloca, locFrom);
il.EmitGetValueOrDefault(typeFrom);
Type nnTypeFrom = TypeUtils.GetNonNullableType(typeFrom);
Type nnTypeTo = TypeUtils.GetNonNullableType(typeTo);
il.EmitConvertToType(nnTypeFrom, nnTypeTo, isChecked);
// construct result type
ConstructorInfo ci = typeTo.GetConstructor(new Type[] { nnTypeTo });
il.Emit(OpCodes.Newobj, ci);
il.Emit(OpCodes.Stloc, locTo);
labEnd = il.DefineLabel();
il.Emit(OpCodes.Br_S, labEnd);
// if null then create a default one
il.MarkLabel(labIfNull);
il.Emit(OpCodes.Ldloca, locTo);
il.Emit(OpCodes.Initobj, typeTo);
il.MarkLabel(labEnd);
il.Emit(OpCodes.Ldloc, locTo);
}
private static void EmitNullableToNonNullableStructConversion(this ILGenerator il, Type typeFrom, Type typeTo, bool isChecked)
{
Debug.Assert(TypeUtils.IsNullableType(typeFrom));
Debug.Assert(!TypeUtils.IsNullableType(typeTo));
Debug.Assert(typeTo.IsValueType);
LocalBuilder locFrom = null;
locFrom = il.DeclareLocal(typeFrom);
il.Emit(OpCodes.Stloc, locFrom);
il.Emit(OpCodes.Ldloca, locFrom);
il.EmitGetValue(typeFrom);
Type nnTypeFrom = TypeUtils.GetNonNullableType(typeFrom);
il.EmitConvertToType(nnTypeFrom, typeTo, isChecked);
}
private static void EmitNonNullableToNullableConversion(this ILGenerator il, Type typeFrom, Type typeTo, bool isChecked)
{
Debug.Assert(!TypeUtils.IsNullableType(typeFrom));
Debug.Assert(TypeUtils.IsNullableType(typeTo));
LocalBuilder locTo = null;
locTo = il.DeclareLocal(typeTo);
Type nnTypeTo = TypeUtils.GetNonNullableType(typeTo);
il.EmitConvertToType(typeFrom, nnTypeTo, isChecked);
ConstructorInfo ci = typeTo.GetConstructor(new Type[] { nnTypeTo });
il.Emit(OpCodes.Newobj, ci);
il.Emit(OpCodes.Stloc, locTo);
il.Emit(OpCodes.Ldloc, locTo);
}
/// <summary>
/// Emits default(T)
/// Semantics match C# compiler behavior
/// </summary>
internal static void EmitDefault(this ILGenerator il, Type type)
{
switch (Type.GetTypeCode(type))
{
case TypeCode.Object:
case TypeCode.DateTime:
if (type.IsValueType)
{
// Type.GetTypeCode on an enum returns the underlying
// integer TypeCode, so we won't get here.
Debug.Assert(!type.IsEnum);
// This is the IL for default(T) if T is a generic type
// parameter, so it should work for any type. It's also
// the standard pattern for structs.
LocalBuilder lb = il.DeclareLocal(type);
il.Emit(OpCodes.Ldloca, lb);
il.Emit(OpCodes.Initobj, type);
il.Emit(OpCodes.Ldloc, lb);
}
else
{
il.Emit(OpCodes.Ldnull);
}
break;
case TypeCode.Empty:
case TypeCode.String:
case TypeCode.DBNull:
il.Emit(OpCodes.Ldnull);
break;
case TypeCode.Boolean:
case TypeCode.Char:
case TypeCode.SByte:
case TypeCode.Byte:
case TypeCode.Int16:
case TypeCode.UInt16:
case TypeCode.Int32:
case TypeCode.UInt32:
il.Emit(OpCodes.Ldc_I4_0);
break;
case TypeCode.Int64:
case TypeCode.UInt64:
il.Emit(OpCodes.Ldc_I4_0);
il.Emit(OpCodes.Conv_I8);
break;
case TypeCode.Single:
il.Emit(OpCodes.Ldc_R4, default(Single));
break;
case TypeCode.Double:
il.Emit(OpCodes.Ldc_R8, default(Double));
break;
case TypeCode.Decimal:
il.Emit(OpCodes.Ldc_I4_0);
il.Emit(OpCodes.Newobj, typeof(Decimal).GetConstructor(new Type[] { typeof(int) }));
break;
default:
throw ContractUtils.Unreachable;
}
}
