pres.system.tex

   1 \subsection{Overview}
   2 \begin{frame}
   3         \frametitle{Current state of mTask}
   4         \begin{itemize}
   5                 \item Suits our needs as an EDSL
   6                 \item It all seems perfect
   7                 \item \ldots\pause{} but\ldots
   8                 \pause{}
   9                 \item No interaction
  10                 \item Compilation requires reprogramming
  11                 \item Entire system is created and fixed
  12         \end{itemize}
  13 \end{frame}
  14
  15 \begin{frame}
  16         \frametitle{Solution}
  17         \begin{itemize}[<+->]
  18                 \item Reuse mTask
  19                 \item New bytecode backend for mTask
  20                 \item Interpreter on client
  21                 \item Server in iTasks with integration
  22                 \item No taskserver generation, onetime programming
  23                 \item Dynamic task sending
  24         \end{itemize}
  25 \end{frame}
  26
  27 \subsection{Extending mTask}
  28 \begin{frame}[fragile]
  29         \frametitle{Adding a View}
  30         \begin{lstlisting}[language=Clean]
  31 :: ByteCode a p = BC (RWS () [BC] BCState ())
  32 :: BC           = BCNop | BCPush BCValue | ...
  33 :: BCValue      = E.e: BCValue e              & mTaskType, TC e
  34 :: BCShare      = { sdsi   :: Int, sdsval :: BCValue, sdsname :: String    }
  35 :: BCState      = { freshl :: Int, freshs :: Int,     sdss    :: [BCShare] }
  36
  37 instance ByteCode arith, boolExpr, ...
  38         \end{lstlisting}
  39 \end{frame}
  40
  41 \begin{frame}[fragile]
  42         \frametitle{Implementation}
  43         \begin{itemize}
  44                 \item Writing instruction
  45                 \item Carrying state
  46                 \item Hand-crafted helpers
  47         \end{itemize}
  48         \begin{lstlisting}[language=Clean]
  49 op2 :: (ByteCode a p1) (ByteCode a p2) BC -> ByteCode b Expr
  50 op2 (BC x) (BC y) bc = BC (x >>| y >>| tell [bc])
  51
  52 tell2 :: [BC] -> (ByteCode a p)
  53 tell2 x = BC (tell x)
  54
  55 instance arith ByteCode where
  56         lit x = tell2 [BCPush (BCValue x)]
  57         (+.) x y = op2 x y BCAdd
  58         ...
  59         \end{lstlisting}
  60 \end{frame}
  61
  62 \begin{frame}[fragile]
  63         \frametitle{Control flow}
  64         \begin{itemize}
  65                 \item Use labels
  66                 \item Label resolving
  67                 \pause{}
  68                 \item Thus no reuse
  69         \end{itemize}
  70         \pause{}
  71         \begin{lstlisting}[language=Clean]
  72 :: BC = ... | BCLab Int | ...
  73
  74 freshlabel = get >>= \st=:{freshl}->put {st & freshl=freshl+1} >>| pure freshl
  75
  76 instance If ByteCode Stmt Stmt Stmt where If b t e = BCIfStmt b t e
  77 ...
  78 BCIfStmt (BC b) (BC t) (BC e) = BC (
  79         freshlabel >>= \else->freshlabel >>= \endif->
  80         b >>| tell [BCJmpF else] >>|
  81         t >>| tell [BCJmp endif, BCLab else] >>|
  82         e >>| tell [BCLab endif]
  83         )
  84         \end{lstlisting}
  85 \end{frame}
  86
  87 \begin{frame}[fragile]
  88         \frametitle{Assignment and SDSs}
  89         \begin{lstlisting}[language=Clean]
  90 instance sds ByteCode where
  91         sds f = {main = BC (freshshare
  92                         >>= \sdsi->pure {BCShare|sdsname="",sdsi=sdsi,sdsval=BCValue 0}
  93                         >>= \sds->pure (f (tell2 [BCSdsFetch sds]))
  94                         >>= \(v In bdy)->modify (addSDS sds v)
  95                         >>| unBC (unMain bdy))
  96                 }
  97
  98 instance assign ByteCode where
  99         (=.) (BC v) (BC e) = BC (e >>| censor makeStore v)
 100
 101 instance sdspub ByteCode where
 102         pub (BC x) = BC (censor (\[BCSdsFetch s]->[BCSdsPublish s]) x)
 103
 104 makeStore [BCSdsFetch i]    = [BCSdsStore i]
 105 makeStore [BCDigitalRead i] = [BCDigitalWrite i]
 106 makeStore [...]             = [...]
 107         \end{lstlisting}
 108 \end{frame}
 109
 110 \begin{frame}[fragile]
 111         \frametitle{Bandwidth is scarce}
 112         Publish SDS explicitly
 113         \pause{}
 114         \begin{lstlisting}
 115 class sdspub v where
 116         pub :: (v t Upd) -> (v () Stmt)
 117 instance sdspub ByteCode where
 118         pub (BC x) = BC (censor (\[BCSdsFetch s]->[BCSdsPublish s]) x)
 119         \end{lstlisting}
 120 \end{frame}
 121
 122 \begin{frame}[fragile]
 123         \frametitle{Task scheduling}
 124         \begin{block}{Old}
 125                 \begin{itemize}
 126                         \item Task server
 127                         \item Tasks start other tasks
 128                 \end{itemize}
 129         \end{block}
 130         \pause{}
 131         \begin{block}{New}
 132                 \begin{itemize}
 133                         \item Old system, taskserver, tasks start tasks
 134                         \item New system, task+strategy
 135                                 \pause{}
 136                                 \begin{itemize}
 137                                         \item \CI{OnShot}
 138                                         \item \CI{OnInterval}
 139                                         \item \CI{OnInterrupt}
 140                                 \end{itemize}
 141                         \pause{}
 142                         \item How to handle termination
 143                 \end{itemize}
 144                 \pause{}
 145                 \begin{lstlisting}[language=Clean]
 146 class retrn v where
 147         retrn :: v () Expr
 148                 \end{lstlisting}
 149         \end{block}
 150 \end{frame}
 151
 152 \subsection{Interpretation}
 153 \begin{frame}[fragile]
 154         \frametitle{mTask implementation}
 155         %TODO
 156 \end{frame}
 157
 158 \subsection{Devices}
 159 \begin{frame}
 160         \frametitle{Devices}
 161         \begin{itemize}
 162                 \item Standard C
 163                 \item Implement some classes in interface
 164                 \pause{}
 165                 \item How to handle termination
 166         \end{itemize}
 167 \end{frame}
 168
 169 \subsection{Server}
 170 \begin{frame}[fragile]
 171         \frametitle{SDS (2)}
 172         \framesubtitle{Parametric Lenses}
 173         \begin{block}{What is the \CI{p} for in \CI{RWShared p r w}}
 174                 \pause{}
 175                 \begin{itemize}
 176                         \item Parameter fixed when writing
 177                         \item Used for notifications
 178                         \item On write the SDS returns \CI{p -> Bool}
 179                 \end{itemize}
 180         \end{block}
 181 %
 182 %       \begin{lstlisting}
 183 %sdsFocus :: p1 (RWShared p1 r w) -> RWShared p2 r w | iTask p
 184 %
 185 %:: SDSNotifyPred p :== p -> Bool
 186 %:: SDSLensRead p r rs     = SDSRead        (p -> rs -> MaybeError TaskException r)
 187 %                          | SDSReadConst   (p -> r)
 188 %:: SDSLensWrite p w rs ws = SDSWrite       (p -> rs -> w -> MaybeError TaskException (Maybe ws))
 189 %                          | SDSWriteConst  (p -> w -> MaybeError TaskException (Maybe ws))
 190 %:: SDSLensNotify p w rs   = SDSNotify      (p -> rs -> w -> SDSNotifyPred p)
 191 %                          | SDSNotifyConst (p -> w -> SDSNotifyPred p)
 192 %
 193 %sdsLens :: String (p -> ps) (SDSLensRead p r rs) (SDSLensWrite p w rs ws)
 194 %       (SDSLensNotify p w rs) (RWShared ps rs ws) -> RWShared p r w | iTask ps
 195 %       \end{lstlisting}
 196 \end{frame}
 197 \subsection{Examples}