protected override void EmitRead(Compiler.CompilerContext ctx, Compiler.Local valueFrom)
{
using (Compiler.Local oldList = AppendToCollection ? ctx.GetLocalWithValue(ExpectedType, valueFrom) : null)
using(Compiler.Local builder = new Compiler.Local(ctx, builderFactory.ReturnType))
{
ctx.EmitCall(builderFactory);
ctx.StoreValue(builder);
if(AppendToCollection)
{
Compiler.CodeLabel done = ctx.DefineLabel();
if(!ExpectedType.IsValueType)
{
ctx.LoadValue(oldList);
ctx.BranchIfFalse(done, false); // old value null; nothing to add
}
PropertyInfo prop = Helpers.GetProperty(ExpectedType, "Length", false);
if(prop == null) prop = Helpers.GetProperty(ExpectedType, "Count", false);
#if !NO_GENERICS
if (prop == null) prop = Helpers.GetProperty(ResolveIReadOnlyCollection(ExpectedType, Tail.ExpectedType), "Count", false);
#endif
ctx.LoadAddress(oldList, oldList.Type);
ctx.EmitCall(Helpers.GetGetMethod(prop, false, false));
ctx.BranchIfFalse(done, false); // old list is empty; nothing to add
Type voidType = ctx.MapType(typeof(void));
if(addRange != null)
{
ctx.LoadValue(builder);
ctx.LoadValue(oldList);
ctx.EmitCall(addRange);
if (addRange.ReturnType != null && add.ReturnType != voidType) ctx.DiscardValue();
}
else
{
// loop and call Add repeatedly
MethodInfo moveNext, current, getEnumerator = GetEnumeratorInfo(ctx.Model, out moveNext, out current);
Helpers.DebugAssert(moveNext != null);
Helpers.DebugAssert(current != null);
Helpers.DebugAssert(getEnumerator != null);
Type enumeratorType = getEnumerator.ReturnType;
using (Compiler.Local iter = new Compiler.Local(ctx, enumeratorType))
{
ctx.LoadAddress(oldList, ExpectedType);
ctx.EmitCall(getEnumerator);
ctx.StoreValue(iter);
using (ctx.Using(iter))
{
Compiler.CodeLabel body = ctx.DefineLabel(), next = ctx.DefineLabel();
ctx.Branch(next, false);
ctx.MarkLabel(body);
ctx.LoadAddress(builder, builder.Type);
ctx.LoadAddress(iter, enumeratorType);
ctx.EmitCall(current);
ctx.EmitCall(add);
if (add.ReturnType != null && add.ReturnType != voidType) ctx.DiscardValue();
ctx.MarkLabel(@next);
ctx.LoadAddress(iter, enumeratorType);
ctx.EmitCall(moveNext);
ctx.BranchIfTrue(body, false);
}
}
}
ctx.MarkLabel(done);
}
EmitReadList(ctx, builder, Tail, add, packedWireType, false);
ctx.LoadAddress(builder, builder.Type);
ctx.EmitCall(finish);
if(ExpectedType != finish.ReturnType)
{
ctx.Cast(ExpectedType);
}
}
}