compiler.scala
changeset 506 8e633f1d0d38
equal deleted inserted replaced
505:d5476854428c 506:8e633f1d0d38
       
     1 
       
     2 type Num = Int
       
     3 type Idn = String
       
     4 
       
     5 var counter = -1
       
     6 // for generating new variables
       
     7 
       
     8 def Fresh(x: Idn) = {
       
     9   counter += 1
       
    10   x ++ "_" ++ counter.toString()
       
    11 }
       
    12 
       
    13 def commas(s: List[String]) : String = s match {
       
    14   case Nil => ""
       
    15   case s::Nil => s
       
    16   case s::ss => s + "," + commas(ss)
       
    17 }
       
    18 def cutlines(s: List[String]) : String = s match {
       
    19   case Nil => ""
       
    20   case s::ss => s + "\n" + cutlines(ss)
       
    21 }
       
    22 
       
    23 
       
    24 abstract class Prim
       
    25 case class PLUS() extends Prim { override def toString = " + " }
       
    26 case class MINUS() extends Prim { override def toString = " - " }
       
    27 case class MULT() extends Prim { override def toString = " * " }
       
    28 
       
    29 abstract class FTerm
       
    30 case class FVar(x : Idn) extends FTerm { override def toString = x }
       
    31 case class FNum(i : Num) extends FTerm { override def toString = i.toString }
       
    32 case class FFix(x : Idn, x1: Idn, e : FTerm) extends FTerm {
       
    33   override def toString = "fix " + x + "(" + x1 + ")" + "." + e 
       
    34 }
       
    35 case class FApp(e1 : FTerm, e2 : FTerm) extends FTerm {
       
    36   override def toString = "(" + e1 + ") (" + e2 + ")"
       
    37 }
       
    38 case class FTuple(es : List[FTerm]) extends FTerm {
       
    39   override def toString = "<" + commas(es.map(_.toString)) + ">"
       
    40 }
       
    41 case class FProj(i : Num, e : FTerm) extends FTerm {
       
    42   override def toString = "proj " + i.toString + " " + e
       
    43 }
       
    44 case class FPrimOp(e1 : FTerm, p : Prim, e2 : FTerm) extends FTerm {
       
    45   override def toString = e1 + p.toString + e2
       
    46 }
       
    47 case class FIf0(e1 : FTerm, e2 : FTerm, e3 : FTerm) extends FTerm {
       
    48   override def toString = "if0(" + e1 + "," + e2 + "," + e3 + ")"
       
    49 }
       
    50 
       
    51 
       
    52 abstract class KTerm
       
    53 abstract class KVal
       
    54 
       
    55 case class KApp(v : KVal, vs : List[KVal]) extends KTerm {
       
    56   override def toString = v + "(" + commas(vs.map(_.toString)) + ")" 
       
    57 }
       
    58 case class KIf0(v : KVal, e1 : KTerm, e2 : KTerm) extends KTerm {
       
    59   override def toString = "if0(" + v + "," + e1 + "," + e2 + ")"
       
    60 }
       
    61 case class KHalt(v : KVal) extends KTerm { override def toString = "halt " + v }
       
    62 case class KLet(x : Idn, v : KVal, e : KTerm) extends KTerm {
       
    63   override def toString = "let " + x + " = " + v + " in " + e
       
    64 }
       
    65 case class KLetProj(x : Idn, i : Num, v : KVal, e : KTerm) extends KTerm {
       
    66   override def toString = "let " + x + " =" + i + " " + v + " in " + e
       
    67 }
       
    68 case class KLetPrimOp(x : Idn, v1 : KVal, p : Prim, v2 : KVal, e : KTerm) extends KTerm {
       
    69   override def toString = "let " + x + " = " + v1 + p + v2 + " in " + e
       
    70 }
       
    71 
       
    72 
       
    73 case class KVVar(x : Idn) extends KVal { override def toString = x }
       
    74 case class KVNum(i : Num) extends KVal { override def toString = i.toString }
       
    75 case class KVTuple(vs : List[KVal]) extends KVal {
       
    76   override def toString = "<" + commas(vs.map(_.toString)) + ">"
       
    77 }
       
    78 case class KVFix(x : Idn, args : List[Idn], e : KTerm) extends KVal {
       
    79   override def toString = "fix " + x + "(" + commas(args) + ")." + e
       
    80 }
       
    81 
       
    82 // CPS tail translation
       
    83 def CPST(e: FTerm) : (KVal => KTerm) = e match {
       
    84   case FVar(x) => (c: KVal) => KApp(c, List(KVVar(x))) 
       
    85   case FNum(i) => (c: KVal) => KApp(c, List(KVNum(i))) 
       
    86   case FIf0(e1, e2, e3) => (c: KVal) => {
       
    87     val e1_prime = CPS(e1)
       
    88     val e2_prime = CPST(e2)
       
    89     val e3_prime = CPST(e3)
       
    90     e1_prime((y: KVal) => KIf0(y, e2_prime(c), e3_prime(c)))
       
    91   }
       
    92   case FPrimOp(e1, op, e2) => (c: KVal) => {
       
    93     val z = Fresh("z")
       
    94     val e1_prime = CPS(e1)
       
    95     val e2_prime = CPS(e2)
       
    96     e1_prime((y1: KVal) => 
       
    97       e2_prime((y2: KVal) => 
       
    98         KLetPrimOp(z, y1, op, y2, KApp(c, List(KVVar(z))))))
       
    99   }
       
   100   case FFix(x, x1, e) => (c: KVal) => {
       
   101     val c_prime = Fresh("c'")
       
   102     val e_prime = CPST(e)
       
   103     KApp(c, List(KVFix(x, List(x1, c_prime), e_prime(KVVar(c_prime)))))
       
   104   }
       
   105   case FApp(e1, e2) => (c: KVal) => {
       
   106     val e1_prime = CPS(e1)
       
   107     val e2_prime = CPS(e2)
       
   108     e1_prime((y1: KVal) => 
       
   109       e2_prime((y2: KVal) => 
       
   110         KApp(y1, List(y2, c))))
       
   111   }
       
   112   case FTuple(es) => (c: KVal) => {
       
   113     def aux(es: List[FTerm], vs: List[KVal]) : KTerm = es match {
       
   114       case Nil => KApp(c, vs.reverse)
       
   115       case (e::es) => CPS(e)((y: KVal) => aux(es, y::vs)) 
       
   116     }
       
   117     aux(es, Nil) 
       
   118   }
       
   119   case FProj(i, e) => (c: KVal) => {
       
   120     val z = Fresh("z")
       
   121     CPS(e)((y: KVal) => KLetProj(z, i, y, KApp(c, List(KVVar(z)))))
       
   122   }
       
   123 }
       
   124 
       
   125 // CPS translation
       
   126 def CPS(e: FTerm) : (KVal => KTerm) => KTerm = e match {
       
   127   case FVar(i) => (k: KVal => KTerm) => k(KVVar(i)) 
       
   128   case FNum(i) => (k: KVal => KTerm) => k(KVNum(i)) 
       
   129   case FFix(x, x1, e) => (k: KVal => KTerm) => {
       
   130     val c = Fresh("c")
       
   131     val e_prime = CPST(e)
       
   132     k(KVFix(x, List(x1, c), e_prime(KVVar(c))))
       
   133   }
       
   134   case FApp(e1, e2) => (k: KVal => KTerm) => {
       
   135     val fr = Fresh("")
       
   136     val z = Fresh("z")
       
   137     val e1_prime = CPS(e1)
       
   138     val e2_prime = CPS(e2)
       
   139     e1_prime((y1: KVal) => 
       
   140       e2_prime((y2: KVal) =>
       
   141         KApp(y1, List(y2, KVFix(fr, List(z), k(KVVar(z)))))))
       
   142   }
       
   143   case FIf0(e1, e2, e3) => (k: KVal => KTerm) => {
       
   144     val fr = Fresh("")
       
   145     val c = Fresh("c")
       
   146     val z = Fresh("z")
       
   147     val e1_prime = CPS(e1)
       
   148     val e2_prime = CPST(e2)
       
   149     val e3_prime = CPST(e3)
       
   150     e1_prime((y: KVal) =>
       
   151       KLet(c, KVFix(fr, List(z), k(KVVar(z))),  
       
   152                 KIf0(y, e2_prime(KVVar(c)), e3_prime(KVVar(c)))))
       
   153   }
       
   154   case FPrimOp(e1, op, e2) => (k: KVal => KTerm) => {
       
   155     val z = Fresh("z")
       
   156     val e1_prime = CPS(e1)
       
   157     val e2_prime = CPS(e2)
       
   158     e1_prime((y1: KVal) => e2_prime((y2: KVal) => KLetPrimOp(z, y1, op, y2, k(KVVar(z)))))
       
   159   }
       
   160   case FTuple(es) => (k: KVal => KTerm) => {
       
   161     def aux(es: List[FTerm], vs: List[KVal]) : KTerm = es match {
       
   162       case Nil => k(KVTuple(vs.reverse))
       
   163       case (e::es) => CPS(e)((y: KVal) => aux(es, y::vs)) 
       
   164     }
       
   165     aux(es, Nil) 
       
   166   }
       
   167   case FProj(i, e) => (k: KVal => KTerm) => {
       
   168     val z = Fresh("z")
       
   169     CPS(e)((y: KVal) => KLetProj(z, i, y, k(KVVar(z))))
       
   170   }
       
   171 }
       
   172 
       
   173 
       
   174 
       
   175 //free variable function
       
   176 def FVKval(v: KVal) : Set[Idn] = v match {
       
   177   case KVVar(x) => Set(x)
       
   178   case KVNum(i) => Set()
       
   179   case KVTuple(vs) => vs.flatMap{FVKval}.toSet
       
   180   case KVFix(x, args, e) => FVKexp(e) -- args - x 
       
   181 }
       
   182 
       
   183 def FVKexp(e: KTerm) : Set[Idn] = e match {
       
   184   case KApp(v, vs) => FVKval(v) ++ vs.flatMap{FVKval}.toSet
       
   185   case KIf0(v, e1, e2) => FVKval(v) ++ FVKexp(e1) ++ FVKexp(e2)
       
   186   case KHalt(v) => FVKval(v)
       
   187   case KLet(x, v, e) => FVKval(v) ++ (FVKexp(e) - x) 
       
   188   case KLetProj(x, i, v, e) => FVKval(v) ++ (FVKexp(e) - x)
       
   189   case KLetPrimOp(x, v1, p, v2, e) => (FVKexp(e) - x) ++ FVKval(v1) ++ FVKval(v2)
       
   190 }
       
   191 
       
   192 
       
   193 abstract class CTerm 
       
   194 abstract class CVal 
       
   195 
       
   196 case class CApp(v : CVal, vs : List[CVal]) extends CTerm  {
       
   197   override def toString = v + "(" + commas(vs.map(_.toString)) + ")"
       
   198 }
       
   199 case class CIf0(v : CVal, e1 : CTerm, e2 : CTerm) extends CTerm {
       
   200   override def toString = "if0(" + v + "," + e1 + "," + e2 + ")"
       
   201 }
       
   202 case class CHalt(v : CVal) extends CTerm { override def toString = "halt " + v }
       
   203 case class CLet(x : Idn, v : CVal, e : CTerm) extends CTerm {
       
   204   override def toString = "let " + x + " = " + v + " in\n" + e
       
   205 }
       
   206 case class CLetProj(x : Idn, i : Num, v : CVal, e : CTerm) extends CTerm {
       
   207   override def toString = "let " + x + " =" + i + " " + v + " in\n" + e
       
   208 }
       
   209 case class CLetPrimOp(x : Idn, v1 : CVal, p : Prim, v2 : CVal, e : CTerm) extends CTerm {
       
   210   override def toString = "let " + x + " =" + v1 + p + v2 + " in\n" + e
       
   211 }
       
   212 
       
   213 case class CVVar(x : Idn) extends CVal { override def toString = x }
       
   214 case class CVNum(i : Num) extends CVal { override def toString = i.toString }
       
   215 case class CVTuple(vs : List[CVal]) extends CVal {
       
   216   override def toString = "<" + commas(vs.map(_.toString)) + ">"
       
   217 }
       
   218 case class CVFixCode(x : Idn, args : List[Idn], e : CTerm) extends CVal {
       
   219   override def toString = "fixcode " + x + "(" + commas(args) + ")." + e 
       
   220 }
       
   221 
       
   222 
       
   223 
       
   224 // closure conversion
       
   225 def CExp(e: KTerm) : CTerm = e match {
       
   226   case KApp(v, vs) => {
       
   227     val z = Fresh("z")
       
   228     val z_code = Fresh("zcode")
       
   229     val z_env = Fresh("zenv")
       
   230     CLet(z, CVal(v), 
       
   231       CLetProj(z_code, 0, CVVar(z),
       
   232         CLetProj(z_env, 1, CVVar(z),
       
   233           CApp(CVVar(z_code), CVVar(z_env) :: vs.map{CVal}))))       
       
   234   }
       
   235   case KIf0(v, e1, e2) => CIf0(CVal(v), CExp(e1), CExp(e2))
       
   236   case KHalt(v) => CHalt(CVal(v))
       
   237   case KLet(x, v, e) => CLet(x, CVal(v), CExp(e))
       
   238   case KLetProj(x, i, v, e) => CLetProj(x, i, CVal(v), CExp(e))
       
   239   case KLetPrimOp(x, v1, p, v2, e) => CLetPrimOp(x, CVal(v1), p, CVal(v2), CExp(e))
       
   240 }
       
   241 
       
   242 def CVal(v: KVal) : CVal = v match {
       
   243   case KVVar(x) => CVVar(x)
       
   244   case KVNum(i) => CVNum(i)
       
   245   case KVTuple(vs) => CVTuple(vs.map{CVal})
       
   246   case KVFix(x, args, e) => {
       
   247     val x_env = Fresh(x + ".env")
       
   248     val ys = FVKval(KVFix(x, args, e)).toList
       
   249     val ys_index = 
       
   250       ys.zipWithIndex.foldRight(CExp(e)) {case ((x, n), e) => CLetProj(x, n, CVVar(x_env), e) } 
       
   251     val v_code = CVFixCode(x, x_env :: args, ys_index)
       
   252     val v_env = CVTuple(ys.map{CVVar(_)})
       
   253     CVTuple(List(v_code, v_env))
       
   254   }
       
   255 }
       
   256 
       
   257 abstract class HTerm
       
   258 abstract class HVal { 
       
   259   def eval(env: Map[Idn, HVal]) : HVal
       
   260 }
       
   261 
       
   262 case class HApp(v : HVal, vs : List[HVal]) extends HTerm {
       
   263   override def toString =  v + "(" + commas (vs.map(_.toString)) + ")" 
       
   264 }
       
   265 case class HIf0(v : HVal, e1 : HTerm, e2 : HTerm) extends HTerm {
       
   266   override def toString = "if0(" + v + "," + e1 + "," + e2 + ")"
       
   267 }
       
   268 case class HHalt(v : HVal) extends HTerm { 
       
   269   override def toString = "halt " + v 
       
   270 }
       
   271 case class HLet(x : Idn, v : HVal, e : HTerm) extends HTerm {
       
   272   override def toString = "let " + x + " = " + v + " in\n" + e
       
   273 }
       
   274 case class HLetProj(x : Idn, i : Num, v : HVal, e : HTerm) extends HTerm {
       
   275   override def toString = "let " + x + " =" + i + " " + v + " in\n" + e
       
   276 }
       
   277 case class HLetPrimOp(x : Idn, v1 : HVal, p : Prim, v2 : HVal, e : HTerm) extends HTerm {
       
   278   override def toString = "let " + x + " = " + v1 + p + v2 + " in\n" + e
       
   279 }
       
   280 
       
   281 case class HVVar(x : Idn) extends HVal { 
       
   282   override def toString = x 
       
   283   def eval(env: Map[Idn, HVal]) : HVal = env(x)
       
   284 }
       
   285 case class HVNum(i : Num) extends HVal { 
       
   286   override def toString = i.toString 
       
   287   def eval(env: Map[Idn, HVal]) : HVal = HVNum(i)
       
   288 }
       
   289 case class HVTuple(vs : List[HVal]) extends HVal {
       
   290   override def toString = "<" + commas (vs.map(_.toString)) + ">"
       
   291   def eval(env: Map[Idn, HVal]) : HVal = HVTuple(vs.map(_.eval(env)))
       
   292 }
       
   293 case class HVLabel(l: Idn) extends HVal { 
       
   294   override def toString = l 
       
   295   def eval(env: Map[Idn, HVal]) : HVal = HVLabel(l)
       
   296 }
       
   297 
       
   298 
       
   299 case class HBlock(args: List[Idn], term: HTerm) {
       
   300   override def toString = "code(" + commas(args) + ").\n" + term + "\n"
       
   301 }
       
   302 
       
   303 case class HProg(blocks: Map[Idn, HBlock], term: HTerm) {
       
   304   override def toString = "\nheap:\n" +
       
   305     cutlines(blocks.toList.map(_ match { case (x, y) => x + " -> " + y.toString })) +
       
   306       "in start:\n" + term.toString 
       
   307 
       
   308   def run_block(pretty: Boolean, l: Idn, as: List[HVal], env: Map[Idn, HVal]) : Unit = {
       
   309     val blk = blocks(l)
       
   310     val env_prime = (blk.args zip as).toMap  
       
   311     if (pretty) println("Referenced: " + l + " -> " + blk)
       
   312     run(pretty, blk.term, env ++ env_prime)
       
   313   }
       
   314 
       
   315   def run(pretty: Boolean, e: HTerm, env: Map[Idn, HVal]) : Unit = {
       
   316     if (pretty) println("Env:" + env.toList.length  + " stored values)\n" + 
       
   317                         cutlines(env.toList.sortBy {_._1}.map(_.toString)))
       
   318     if (pretty) println("Term:\n" + e.toString)
       
   319     if (pretty) Console.readLine
       
   320     e match {
       
   321       case HHalt(v) => println ("Finished with result " + v.eval(env))
       
   322       case HApp(v, vs) => (v.eval(env), vs.map(_.eval(env))) match {
       
   323         case (HVLabel(l), vs) => run_block(pretty, l, vs, env)
       
   324         case _ => throw new IllegalArgumentException("not a label")
       
   325       }
       
   326       case HLet(x, v, e) => run(pretty, e, env + (x -> v.eval(env)))
       
   327       case HLetProj(x, i, v, e) => v.eval(env) match {
       
   328         case HVTuple(vs) => run(pretty, e, env + (x -> vs(i)))
       
   329         case _ => throw new IllegalArgumentException("not a tuple")
       
   330       }
       
   331       case HLetPrimOp(x, v1, p, v2, e) => (v1.eval(env), p, v2.eval(env)) match {
       
   332         case (HVNum(m), PLUS(), HVNum(n)) =>  run(pretty, e, env + (x -> HVNum(m + n)))
       
   333         case (HVNum(m), MINUS(), HVNum(n)) => run(pretty, e, env + (x -> HVNum(m - n)))
       
   334         case (HVNum(m), MULT(), HVNum(n)) =>  run(pretty, e, env + (x -> HVNum(m * n)))
       
   335         case _ => throw new IllegalArgumentException("not a number")
       
   336       }
       
   337       case HIf0(v, e1, e2) => v.eval(env) match {
       
   338         case HVNum(0) => run(pretty, e1, env)
       
   339         case _ => run(pretty, e2, env) 
       
   340       }
       
   341     }
       
   342   }
       
   343   
       
   344   def run_prog(pretty: Boolean) = run(pretty, term, Map())
       
   345 }
       
   346 
       
   347 
       
   348 
       
   349 // hoisting
       
   350 def H(e: CTerm, ls: Map[Idn, HVal]) : (HTerm, Map[Idn, HBlock]) = e match {
       
   351   case CApp(v, vs) => {
       
   352     val (v_prime, hs) = HV(v, ls)
       
   353     val (vs_prime, hss) = vs.map{HV(_, ls)}.unzip
       
   354     (HApp(v_prime, vs_prime), hs ++ hss.flatten)
       
   355   }
       
   356   case CIf0(v, e1, e2) => {
       
   357     val (v_prime, hs1) = HV(v, ls)
       
   358     val (e1_prime, hs2) = H(e1, ls)
       
   359     val (e2_prime, hs3) = H(e2, ls)
       
   360     (HIf0(v_prime, e1_prime, e2_prime), hs1 ++ hs2 ++ hs3)
       
   361   }
       
   362   case CHalt(v) => {
       
   363     val (v_prime, hs) = HV(v, ls) 
       
   364     (HHalt(v_prime), hs)
       
   365   }
       
   366   case CLet(x, v, e) => {
       
   367     val (v_prime, hs1) = HV(v, ls)
       
   368     val (e_prime, hs2) = H(e, ls)
       
   369     (HLet(x, v_prime, e_prime), hs1 ++ hs2)
       
   370   }
       
   371   case CLetProj(x, i, v, e) => {
       
   372     val (v_prime, hs1) = HV(v, ls)
       
   373     val (e_prime, hs2) = H(e, ls)
       
   374     (HLetProj(x, i, v_prime, e_prime), hs1 ++ hs2)
       
   375   }
       
   376   case CLetPrimOp(x, v1, p, v2, e) => {
       
   377     val (v1_prime, hs1) = HV(v1, ls)
       
   378     val (v2_prime, hs2) = HV(v2, ls)
       
   379     val (e_prime, hs3) = H(e, ls)
       
   380     (HLetPrimOp(x, v1_prime, p, v2_prime, e_prime), hs1 ++ hs2 ++ hs3)
       
   381   }
       
   382 }
       
   383 
       
   384 def HV(v: CVal, ls: Map[Idn, HVal]) : (HVal, Map[Idn, HBlock]) = v match {
       
   385   case CVVar(x) => ls.get(x) match {
       
   386     case Some(v) => (v, Map())
       
   387     case None => (HVVar(x), Map())
       
   388   }
       
   389   case CVNum(i) => (HVNum(i), Map())
       
   390   case CVTuple(vs) => {
       
   391     val (vs_prime, hss) = vs.map{HV(_, ls)}.unzip
       
   392     (HVTuple(vs_prime), hss.flatten.toMap)
       
   393   }
       
   394   case CVFixCode(x, args, e) => {
       
   395     val l = Fresh(x + ".block")
       
   396     val (e_prime, hs) = H(e, ls + (x -> HVTuple(List(HVLabel(l), HVVar(args.head)))))
       
   397     (HVLabel(l), hs + (l -> HBlock(args, e_prime)))
       
   398   } 
       
   399 }
       
   400 
       
   401 def HP(e: CTerm) = {
       
   402   val (e_prime, hs) = H(e, Map())
       
   403   HProg(hs, e_prime)
       
   404 }
       
   405 
       
   406 
       
   407 abstract class TALVal {
       
   408   def eval(regs: Map[Idn, TALVal]) : TALVal
       
   409 }
       
   410 abstract class TALInstr {
       
   411   def update_regs(regs: Map[Idn, TALVal]) :  Map[Idn, TALVal] = regs
       
   412 }
       
   413 
       
   414 case class TALReg(r: Idn) extends TALVal { 
       
   415   override def toString = r 
       
   416   def eval(regs: Map[Idn, TALVal]) = regs(r).eval(regs)
       
   417 }
       
   418 case class TALLabel(l: Idn) extends TALVal { 
       
   419   override def toString = l 
       
   420   def eval(regs: Map[Idn, TALVal]) = TALLabel(l)
       
   421 }
       
   422 case class TALNum(i: Int) extends TALVal { 
       
   423   override def toString = i.toString 
       
   424   def eval(regs: Map[Idn, TALVal]) = TALNum(i)
       
   425 }
       
   426 case class TALTuple(vs: List[TALVal]) extends TALVal {
       
   427   override def toString = "<" + commas (vs.map(_.toString)) + ">"
       
   428   def eval(regs: Map[Idn, TALVal]) = TALTuple(vs.map(_.eval(regs)))
       
   429 }
       
   430 
       
   431 
       
   432 case class TALAdd(r1: Idn, r2: Idn, v: TALVal) extends TALInstr {
       
   433   override def toString = "Add " + r1 + " " + r2 + " " + v
       
   434   override def update_regs (regs: Map[Idn, TALVal]) : Map[Idn, TALVal] = (regs(r2), v) match {
       
   435     case (TALNum(n), TALNum(m)) => regs + (r1 -> TALNum(n + m))
       
   436     case (TALNum(n), TALReg(r3)) => regs(r3) match { 
       
   437       case TALNum(m) => regs + (r1 -> TALNum (n + m))
       
   438       case _ => throw new IllegalArgumentException("not a number")
       
   439     }
       
   440     case _ => throw new IllegalArgumentException("not a number")
       
   441   }
       
   442 }
       
   443 case class TALSub(r1: Idn, r2: Idn, v: TALVal) extends TALInstr {
       
   444   override def toString = "Sub " + r1 + " " + r2 + " " + v
       
   445   override def update_regs (regs: Map[Idn, TALVal]) : Map[Idn, TALVal] = (regs(r2), v) match {
       
   446     case (TALNum(n), TALNum(m)) => regs + (r1 -> TALNum(n - m))
       
   447     case (TALNum(n), TALReg(r3)) => regs(r3) match {
       
   448       case TALNum(m) => regs + (r1 -> TALNum (n - m))
       
   449       case _ => throw new IllegalArgumentException("not a number")
       
   450     }
       
   451     case _ => throw new IllegalArgumentException("not a number")
       
   452   }
       
   453 }
       
   454 case class TALMul(r1: Idn, r2: Idn, v: TALVal) extends TALInstr {
       
   455   override def toString = "Mul " + r1 + " " + r2 + " " + v
       
   456   override def update_regs (regs: Map[Idn, TALVal]) : Map[Idn, TALVal] = (regs(r2), v) match {
       
   457     case (TALNum(n), TALNum(m)) => regs + (r1 -> TALNum (n * m))
       
   458     case (TALNum(n), TALReg(r3)) => regs(r3) match {
       
   459       case TALNum(m) => regs + (r1 -> TALNum (n * m))
       
   460       case _ => throw new IllegalArgumentException("not a number")
       
   461     }
       
   462     case _ => throw new IllegalArgumentException("not a number")
       
   463   }
       
   464 }
       
   465 case class TALBnz(r: Idn, v: TALVal) extends TALInstr {
       
   466   override def toString = "Bnz " + r + " " + v
       
   467 }
       
   468 case class TALMov(r: Idn, v: TALVal) extends TALInstr {
       
   469   override def toString = "Mov " + r + " " + v
       
   470   override def update_regs (regs: Map[Idn, TALVal]) : Map[Idn, TALVal] = v match {
       
   471     case TALReg(r1) => regs + (r -> regs(r1)) 
       
   472     case _ => regs + (r -> v)
       
   473   }
       
   474 }
       
   475 case class TALProj(r1: Idn, r2: Idn, i: Num) extends TALInstr {
       
   476   override def toString = "Ldi " + r1 + " <- " + r2 + "[" + i + "]" 
       
   477   override def update_regs (regs: Map[Idn, TALVal]) : Map[Idn, TALVal] = { 
       
   478     regs(r2) match {
       
   479       case TALTuple(vs) => regs + (r1 -> vs(i)) 
       
   480       case _ => throw new IllegalArgumentException("not a tuple: ")
       
   481     }
       
   482   }
       
   483 }
       
   484 
       
   485 case class TALJmp(v: TALVal) extends TALInstr {
       
   486   override def toString = "Jmp " + v
       
   487 }
       
   488 case class TALHalt() extends TALInstr { 
       
   489   override def toString = "halt" 
       
   490 }
       
   491 
       
   492 
       
   493 case class TALBlock(regs: List[Idn], cs: List[TALInstr]) {
       
   494   override def toString = "code(" + commas(regs) + ").\n" + cutlines(cs.map{_.toString}) + "\n"
       
   495 }
       
   496 
       
   497 case class TALProg(blocks: Map[Idn, TALBlock], start: List[TALInstr]) {
       
   498   override def toString =  "heap:\n" +
       
   499     cutlines(blocks.toList.map(_ match { case (x, y) => x + " -> " + y.toString })) +
       
   500       "start block:\n" + cutlines(start.map(_.toString)) 
       
   501 
       
   502   def run_block(pretty: Boolean, l: Idn, regs: Map[Idn, TALVal]) : Unit = {
       
   503     val blk = blocks(l)
       
   504     if (pretty) println("Referenced: " + l + " -> " + blk)
       
   505     val regs_prime = for ((r, n) <- blk.regs.zipWithIndex) yield (r, TALReg("RArg_" + n.toString).eval(regs))
       
   506     run(pretty, blk.cs, regs ++ regs_prime.toMap)
       
   507   }
       
   508 
       
   509   def run(pretty: Boolean, cs: List[TALInstr], regs: Map[Idn, TALVal]) : Unit = {
       
   510     if (pretty) println("Regs:(" + regs.toList.length  + " stored values)\n" + 
       
   511                         cutlines(regs.toList.sortBy {_._1}.map(_.toString)))
       
   512     if (pretty) println("Instrs:\n" + cutlines(cs.map(_.toString)))
       
   513     if (pretty) Console.readLine
       
   514     cs match {
       
   515       case (TALHalt() :: _) => println ("Finished with result " + regs("RArg_0"))
       
   516       case (TALJmp(TALLabel(l)) :: _) => run_block(pretty, l, regs)
       
   517       case (TALJmp(TALReg(r)) :: _) => regs(r) match {
       
   518         case TALLabel(l) => run_block(pretty, l, regs)
       
   519         case _ => throw new IllegalArgumentException("jump to non-label")
       
   520       }
       
   521       case (TALBnz(r, TALLabel(l)) :: cs) => regs(r) match {
       
   522         case TALNum(0) => run(pretty, cs, regs)
       
   523         case _ => run_block(pretty, l, regs) 
       
   524       }
       
   525       case (c :: cs) => run(pretty, cs, c.update_regs(regs))
       
   526       case Nil => throw new IllegalArgumentException("no instruction left")
       
   527     }
       
   528   } 
       
   529 
       
   530   def run_prog(pretty: Boolean) : Unit = run(pretty, start, Map())
       
   531 }
       
   532 
       
   533 def mk_vreg(s: String) = "Reg_" + s
       
   534 def mk_areg(i: Int) = "RArg_" + i.toString
       
   535   
       
   536 
       
   537 def Tval(v: HVal) : TALVal = v match {
       
   538   case HVVar(x) => TALReg("Reg_" + x)
       
   539   case HVNum(i) => TALNum(i)
       
   540   case HVTuple(vs) => TALTuple(vs.map(Tval)) 
       
   541   case HVLabel(l) => TALLabel(l)
       
   542 }
       
   543 
       
   544 def Texp(e: HTerm) : (Map[Idn, TALBlock], List[TALInstr]) = e match {
       
   545   case HApp(v, vs) => {
       
   546     val fr_reg0 = Fresh("r0") 
       
   547     val fr_regs = vs.map((v) => Fresh("r"))
       
   548     val movs0 = List(TALMov(fr_reg0, Tval(v)))
       
   549     val movs1 = for ((r, v) <- (fr_regs zip vs)) yield TALMov(r, Tval(v))
       
   550     val movs2 = for ((r, i) <- fr_regs.zipWithIndex) yield TALMov(mk_areg(i), TALReg(r))
       
   551     val movs3 = List(TALJmp(TALReg(fr_reg0))) 
       
   552     (Map(), movs0 ::: movs1 ::: movs2 ::: movs3)
       
   553   }
       
   554   case HIf0(v, e1, e2) => {
       
   555     val l = Fresh("else_branch")
       
   556     val r = Fresh("r")
       
   557     val (h1, comp1) = Texp(e1)
       
   558     val (h2, comp2) = Texp(e2)
       
   559     val code = List(TALMov(r, Tval(v)), TALBnz(r, TALLabel(l)))
       
   560     val h3 = TALBlock(Nil, comp2)
       
   561     (h1 ++ h2 + (l -> h3), code ::: comp1)
       
   562   }
       
   563   case HHalt(v) => {
       
   564     (Map(), List(TALMov(mk_areg(0), Tval(v)), TALHalt()))
       
   565   }
       
   566   case HLet(x, v, e) => {
       
   567     val (h, comp) = Texp(e)
       
   568     val code = TALMov(mk_vreg(x), Tval(v))
       
   569     (h, code :: comp)
       
   570   }
       
   571   case HLetPrimOp(x, v1, PLUS(), v2, e) => {
       
   572     val r = mk_vreg(x)
       
   573     val (h, comp) = Texp(e)
       
   574     val code = List(TALMov(r, Tval(v1)), TALAdd(r, r, Tval(v2)))
       
   575     (h, code ::: comp)
       
   576   }
       
   577   case HLetPrimOp(x, v1, MINUS(), v2, e) => {
       
   578     val r = mk_vreg(x)
       
   579     val (h, comp) = Texp(e)
       
   580     val code = List(TALMov(r, Tval(v1)), TALSub(r, r, Tval(v2)))
       
   581     (h, code ::: comp)
       
   582   }
       
   583   case HLetPrimOp(x, v1, MULT(), v2, e) => {
       
   584     val r = mk_vreg(x)
       
   585     val (h, comp) = Texp(e)
       
   586     val code = List(TALMov(r, Tval(v1)), TALMul(r, r, Tval(v2)))
       
   587     (h, code ::: comp)
       
   588   }  
       
   589   case HLetProj(x, i, v, e) => {
       
   590     val r = mk_vreg(x)
       
   591     val (h, comp) = Texp(e)
       
   592     val code = List(TALMov(r, Tval(v)), TALProj(r, r, i))
       
   593     (h, code ::: comp)
       
   594   }
       
   595 }
       
   596 
       
   597 def Tblock(l: Idn, hb: HBlock) : List[(Idn, TALBlock)] = hb match {  
       
   598   case HBlock(args, e) => {
       
   599     val (h, comp) = Texp(e)
       
   600     (l, TALBlock(args.map("Reg_" + _), comp)) :: h.toList
       
   601   }
       
   602 }
       
   603 
       
   604 def Tprog(prog: HProg) = prog match {
       
   605   case HProg(heaps, e) => {
       
   606     val (hs, comp) = Texp(e)
       
   607     val heap_prime = for ((l, hb) <- heaps) yield Tblock(l, hb)
       
   608     TALProg(hs ++ heap_prime.flatten.toMap, comp)
       
   609   }
       
   610 }
       
   611 
       
   612 /* Simple examples
       
   613 
       
   614 // tuple <1,2,3>
       
   615 val prog0 = FTuple(List(FNum(1), FNum(2), FNum(3)))
       
   616 val Kresult0 = CPS(prog0)((y:KVal) => KHalt(y))
       
   617 val Cresult0 = CExp(Kresult0)
       
   618 val Hresult0 = HP(Cresult0)
       
   619 val Tresult0 = Tprog(Hresult0)
       
   620 
       
   621 println("tuple example: \n")
       
   622 println("F: " + prog0.toString)
       
   623 println("K: " + Kresult0.toString)
       
   624 println("C: " + Cresult0.toString)
       
   625 println("H: " + Hresult0.toString)
       
   626 println("T: " + Tresult0.toString + "\n")
       
   627 Tresult0.run_prog(true)
       
   628 Console.readLine
       
   629 
       
   630 // tuple Proj 1 <1,2,3>
       
   631 val prog1 = FProj(1, FTuple(List(FNum(1), FNum(2), FNum(3))))
       
   632 val Kresult1 = CPS(prog1)((y:KVal) => KHalt(y))
       
   633 val Cresult1 = CExp(Kresult1)
       
   634 val Hresult1 = HP(Cresult1)
       
   635 val Tresult1 = Tprog(Hresult1)
       
   636 
       
   637 println("tuple - proj: \n")
       
   638 println("F: " + prog1.toString)
       
   639 println("K: " + Kresult1.toString)
       
   640 println("C: " + Cresult1.toString)
       
   641 println("H: " + Hresult1.toString)
       
   642 println("T: " + Tresult1.toString + "\n")
       
   643 Tresult1.run_prog(true)
       
   644 Console.readLine
       
   645 
       
   646 // 3 + 4
       
   647 val prog2 = FPrimOp(FNum(3),PLUS(),FNum(4))
       
   648 val Kresult2 = CPS(prog2)((y:KVal) => KHalt(y))
       
   649 val Cresult2 = CExp(Kresult2)
       
   650 val Hresult2 = HP(Cresult2)
       
   651 val Tresult2 = Tprog(Hresult2)
       
   652 
       
   653 println("3 + 4: \n")
       
   654 println("F: " + prog2.toString)
       
   655 println("K: " + Kresult2.toString)
       
   656 println("C: " + Cresult2.toString)
       
   657 println("H: " + Hresult2.toString)
       
   658 println("T: " + Tresult2.toString + "\n")
       
   659 Tresult2.run_prog(true)
       
   660 Console.readLine
       
   661 
       
   662 // (fix f(x). 18 * x + 32) 24
       
   663 val d1 = FPrimOp(FPrimOp(FNum(18), MULT(), FVar("x")), PLUS(), FNum(32))
       
   664 val prog3 = FApp(FFix("f", "x", d1), FNum(24))
       
   665 val Kresult3 = CPS(prog3)((y:KVal) => KHalt(y))
       
   666 val Cresult3 = CExp(Kresult3)
       
   667 val Hresult3 = HP(Cresult3)
       
   668 val Tresult3 = Tprog(Hresult3)
       
   669 
       
   670 println("(fix f(x). 18 * x + 32) 24 \n")
       
   671 println("F: " + prog3.toString + "\n")
       
   672 println("K: " + Kresult3.toString + "\n")
       
   673 println("C: " + Cresult3.toString + "\n")
       
   674 println("H: " + Hresult3.toString + "\n")
       
   675 Hresult3.run_prog(true)
       
   676 Console.readLine
       
   677 println("T: " + Tresult3.toString + "\n")
       
   678 Tresult3.run_prog(true)
       
   679 Console.readLine
       
   680 */
       
   681 
       
   682 
       
   683 /*
       
   684 // twice-apply example
       
   685 // fix twice(f)._(x). f (f x)
       
   686 val fun = FFix("id", "x", FPrimOp(FVar("x"), MULT(), FVar("x")))
       
   687 val ffx = FApp(FVar("f"), FApp(FVar("f"), FVar("x")))
       
   688 val f1 = FFix("twice", "f", FFix("twicef", "x", ffx))
       
   689 val prog4 = FApp(FApp(f1, fun), FNum(2))
       
   690 val Kresult4 = CPS(prog4)((y:KVal) => KHalt(y))
       
   691 val Cresult4 = CExp(Kresult4)
       
   692 val Hresult4 = HP(Cresult4)
       
   693 val Tresult4 = Tprog(Hresult4)
       
   694 
       
   695 println("twice fun 2\n")
       
   696 println("F: " + prog4.toString + "\n")
       
   697 println("K: " + Kresult4.toString + "\n")
       
   698 println("C: " + Cresult4.toString + "\n")
       
   699 println("H: " + Hresult4.toString + "\n")
       
   700 //Hresult4.run_prog(false)
       
   701 //Console.readLine
       
   702 println("T: " + Tresult4.toString + "\n")
       
   703 Tresult4.run_prog(false)
       
   704 Console.readLine
       
   705 */
       
   706 
       
   707 /*
       
   708 //identity function
       
   709 //fix id(x). x
       
   710 val id = FFix("id", "x", FVar("x"))
       
   711 val id_three = FApp(id, FNum(3))
       
   712 
       
   713 val Kresult5 = CPS(id_three)((y:KVal) => KHalt(y))
       
   714 val Cresult5 = CExp(Kresult5)
       
   715 val Hresult5 = HP(Cresult5)
       
   716 val Tresult5 = Tprog(Hresult5)
       
   717 
       
   718 println("id 3:")
       
   719 println("F: " + id_three.toString)
       
   720 println("K: " + Kresult5.toString + "\n")
       
   721 println("C: " + Cresult5.toString + "\n")
       
   722 println("H: " + Hresult5.toString + "\n")
       
   723 println("T: " + Tresult5.toString + "\n")
       
   724 Tresult5.run_prog(false)
       
   725 Console.readLine
       
   726 */
       
   727 
       
   728 /*
       
   729 //example: factorial
       
   730 val f = FVar("f")
       
   731 val n = FVar("n")
       
   732 val one = FNum(1)
       
   733 val six = FNum(15)
       
   734 val e0 = FPrimOp(n, MINUS(), one)
       
   735 val e1 = FApp(f, e0)
       
   736 val e2 = FPrimOp(n, MULT(), e1)
       
   737 val fact: FTerm = FFix("f", "n", FIf0(n, one, e2))
       
   738 val fact_six = FApp(fact, six)
       
   739 
       
   740 
       
   741 val Kresult6 = CPS(fact_six)((y:KVal) => KHalt(y))
       
   742 val Cresult6 = CExp(Kresult6)
       
   743 val Hresult6 = HP(Cresult6)
       
   744 val Tresult6 = Tprog(Hresult6)
       
   745 
       
   746 println("fact 6: \n")
       
   747 println("F: " + fact_six)
       
   748 Console.readLine
       
   749 println("K: " + Kresult6.toString + "\n")
       
   750 Console.readLine
       
   751 println("C: " + Cresult6.toString + "\n")
       
   752 Console.readLine
       
   753 println("H: " + Hresult6.toString + "\n")
       
   754 println("-----------------------------")
       
   755 println("Execution")
       
   756 Hresult6.run_prog(false)
       
   757 Console.readLine
       
   758 println("T: " + Tresult6.toString + "\n")
       
   759 println("-----------------------------")
       
   760 println("Execution")
       
   761 Tresult6.run_prog(false)
       
   762 Console.readLine
       
   763 */
       
   764 
       
   765 
       
   766 //example: fibonacci
       
   767 // fib(n).if0(n, 1,if0(n - 1, 1, fib(n - 1) + fib(n - 2))) 
       
   768 val fib = FVar("fib")
       
   769 val n = FVar("n")
       
   770 val one = FNum(1)
       
   771 val two = FNum(2)
       
   772 val minus_one = FPrimOp(n, MINUS(), one)
       
   773 val minus_two = FPrimOp(n, MINUS(), two)
       
   774 val fibonacci = 
       
   775           FFix("fib", "n",
       
   776             FIf0(n, one,
       
   777               FIf0(minus_one, one, FPrimOp(FApp(fib, minus_one), PLUS(), FApp(fib, minus_two)))))
       
   778 val fib_apply = FApp(fibonacci, FNum(4))
       
   779 
       
   780 val Kresult7 = CPS(fib_apply)((y:KVal) => KHalt(y))
       
   781 val Cresult7 = CExp(Kresult7)
       
   782 val Hresult7 = HP(Cresult7)
       
   783 val Tresult7 = Tprog(Hresult7)
       
   784 
       
   785 println("fib: \n")
       
   786 println("F: " + fib_apply)
       
   787 Console.readLine
       
   788 println("K: " + Kresult7.toString + "\n")
       
   789 Console.readLine
       
   790 println("C: " + Cresult7.toString + "\n")
       
   791 Console.readLine
       
   792 println("H: " + Hresult7.toString + "\n")
       
   793 println("-----------------------------")
       
   794 println("H Prog")
       
   795 Hresult7.run_prog(false)
       
   796 Console.readLine
       
   797 println("T: " + Tresult7.toString + "\n")
       
   798 println("-----------------------------")
       
   799 println("TAL")
       
   800 Tresult7.run_prog(false)
       
   801 Console.readLine