void IProtoSerializer.EmitRead(Compiler.CompilerContext ctx, Compiler.Local valueFrom)
{
ProtoTypeCode typeCode = GetTypeCode();
if (map == null)
{
ctx.EmitBasicRead("ReadInt32", ctx.MapType(typeof(int)));
ctx.ConvertFromInt32(typeCode, false);
}
else
{
int[] wireValues = new int[map.Length];
object[] values = new object[map.Length];
for (int i = 0; i < map.Length; i++)
{
wireValues[i] = map[i].WireValue;
values[i] = map[i].RawValue;
}
using (Compiler.Local result = new Compiler.Local(ctx, ExpectedType))
using (Compiler.Local wireValue = new Compiler.Local(ctx, ctx.MapType(typeof(int))))
{
ctx.EmitBasicRead("ReadInt32", ctx.MapType(typeof(int)));
ctx.StoreValue(wireValue);
Compiler.CodeLabel @continue = ctx.DefineLabel();
foreach (BasicList.Group group in BasicList.GetContiguousGroups(wireValues, values))
{
Compiler.CodeLabel tryNextGroup = ctx.DefineLabel();
int groupItemCount = group.Items.Count;
if (groupItemCount == 1)
{
// discreet group; use an equality test
ctx.LoadValue(wireValue);
ctx.LoadValue(group.First);
Compiler.CodeLabel processThisValue = ctx.DefineLabel();
ctx.BranchIfEqual(processThisValue, true);
ctx.Branch(tryNextGroup, false);
WriteEnumValue(ctx, typeCode, processThisValue, @continue, group.Items[0], @result);
}
else
{
// implement as a jump-table-based switch
ctx.LoadValue(wireValue);
ctx.LoadValue(group.First);
ctx.Subtract(); // jump-tables are zero-based
Compiler.CodeLabel[] jmp = new Compiler.CodeLabel[groupItemCount];
for (int i = 0; i < groupItemCount; i++)
{
jmp[i] = ctx.DefineLabel();
}
ctx.Switch(jmp);
// write the default...
ctx.Branch(tryNextGroup, false);
for (int i = 0; i < groupItemCount; i++)
{
WriteEnumValue(ctx, typeCode, jmp[i], @continue, group.Items[i], @result);
}
}
ctx.MarkLabel(tryNextGroup);
}
// throw source.CreateEnumException(ExpectedType, wireValue);
ctx.LoadReaderWriter();
ctx.LoadValue(ExpectedType);
ctx.LoadValue(wireValue);
ctx.EmitCall(ctx.MapType(typeof(ProtoReader)).GetMethod("ThrowEnumException"));
ctx.MarkLabel(@continue);
ctx.LoadValue(result);
}
}
}
