private static void EmitNullableToNullableConversion(this ILGenerator ilGenerator, TypeInfo typeFrom, TypeInfo typeTo, bool isChecked)
{
Label labIfNull = default(Label);
Label labEnd = default(Label);
LocalBuilder locFrom = null;
LocalBuilder locTo = null;
locFrom = ilGenerator.DeclareLocal(typeFrom.AsType());
ilGenerator.Emit(OpCodes.Stloc, locFrom);
locTo = ilGenerator.DeclareLocal(typeTo.AsType());
// test for null
ilGenerator.Emit(OpCodes.Ldloca, locFrom);
ilGenerator.EmitHasValue(typeFrom.AsType());
labIfNull = ilGenerator.DefineLabel();
ilGenerator.Emit(OpCodes.Brfalse_S, labIfNull);
ilGenerator.Emit(OpCodes.Ldloca, locFrom);
ilGenerator.EmitGetValueOrDefault(typeFrom.AsType());
Type nnTypeFrom = TypeInfoUtils.GetNonNullableType(typeFrom);
Type nnTypeTo = TypeInfoUtils.GetNonNullableType(typeTo);
ilGenerator.EmitConvertToType(nnTypeFrom, nnTypeTo, isChecked);
// construct result type
ConstructorInfo ci = typeTo.GetConstructor(new Type[] { nnTypeTo });
ilGenerator.Emit(OpCodes.Newobj, ci);
ilGenerator.Emit(OpCodes.Stloc, locTo);
labEnd = ilGenerator.DefineLabel();
ilGenerator.Emit(OpCodes.Br_S, labEnd);
// if null then create a default one
ilGenerator.MarkLabel(labIfNull);
ilGenerator.Emit(OpCodes.Ldloca, locTo);
ilGenerator.Emit(OpCodes.Initobj, typeTo.AsType());
ilGenerator.MarkLabel(labEnd);
ilGenerator.Emit(OpCodes.Ldloc, locTo);
}
private static void EmitNullableToNonNullableStructConversion(this ILGenerator ilGenerator, TypeInfo typeFrom, TypeInfo typeTo, bool isChecked)
{
LocalBuilder locFrom = null;
locFrom = ilGenerator.DeclareLocal(typeFrom.AsType());
ilGenerator.Emit(OpCodes.Stloc, locFrom);
ilGenerator.Emit(OpCodes.Ldloca, locFrom);
ilGenerator.EmitGetValue(typeFrom.AsType());
Type nnTypeFrom = TypeInfoUtils.GetNonNullableType(typeFrom);
ilGenerator.EmitConvertToType(nnTypeFrom, typeTo.AsType(), isChecked);
}
private static void EmitNonNullableToNullableConversion(this ILGenerator ilGenerator, TypeInfo typeFrom, TypeInfo typeTo, bool isChecked)
{
LocalBuilder locTo = null;
locTo = ilGenerator.DeclareLocal(typeTo.AsType());
Type nnTypeTo = TypeInfoUtils.GetNonNullableType(typeTo);
ilGenerator.EmitConvertToType(typeFrom.AsType(), nnTypeTo, isChecked);
ConstructorInfo ci = typeTo.GetConstructor(new Type[] { nnTypeTo });
ilGenerator.Emit(OpCodes.Newobj, ci);
ilGenerator.Emit(OpCodes.Stloc, locTo);
ilGenerator.Emit(OpCodes.Ldloc, locTo);
}