private void WriteFieldHandler(
Compiler.CompilerContext ctx, Type expected, Compiler.Local loc,
Compiler.CodeLabel handler, Compiler.CodeLabel @continue, IProtoSerializer serializer)
{
ctx.MarkLabel(handler);
Type serType = serializer.ExpectedType;
if (serType == ExpectedType)
{
EmitCreateIfNull(ctx, loc);
serializer.EmitRead(ctx, loc);
}
else
{
//RuntimeTypeModel rtm = (RuntimeTypeModel)ctx.Model;
if (((IProtoTypeSerializer)serializer).CanCreateInstance())
{
Compiler.CodeLabel allDone = ctx.DefineLabel();
ctx.LoadValue(loc);
ctx.BranchIfFalse(allDone, false); // null is always ok
ctx.LoadValue(loc);
ctx.TryCast(serType);
ctx.BranchIfTrue(allDone, false); // not null, but of the correct type
// otherwise, need to convert it
ctx.LoadReader(false);
ctx.LoadValue(loc);
((IProtoTypeSerializer)serializer).EmitCreateInstance(ctx);
ctx.EmitCall(typeof(ProtoReader).GetMethod("Merge",
new[] { typeof(ProtoReader), typeof(object), typeof(object) }));
ctx.Cast(expected);
ctx.StoreValue(loc); // Merge always returns a value
// nothing needs doing
ctx.MarkLabel(allDone);
}
if (Helpers.IsValueType(serType))
{
Compiler.CodeLabel initValue = ctx.DefineLabel();
Compiler.CodeLabel hasValue = ctx.DefineLabel();
using (Compiler.Local emptyValue = new Compiler.Local(ctx, serType))
{
ctx.LoadValue(loc);
ctx.BranchIfFalse(initValue, false);
ctx.LoadValue(loc);
ctx.CastFromObject(serType);
ctx.Branch(hasValue, false);
ctx.MarkLabel(initValue);
ctx.InitLocal(serType, emptyValue);
ctx.LoadValue(emptyValue);
ctx.MarkLabel(hasValue);
}
}
else
{
ctx.LoadValue(loc);
ctx.Cast(serType);
}
serializer.EmitRead(ctx, null);
}
if (serializer.ReturnsValue)
{ // update the variable
if (Helpers.IsValueType(serType))
{
// but box it first in case of value type
ctx.CastToObject(serType);
}
ctx.StoreValue(loc);
}
ctx.Branch(@continue, false); // "continue"
}