mlton/backend/objptr-tycon.fun

   1 (* Copyright (C) 2009 Matthew Fluet.
   2  * Copyright (C) 2004-2007 Henry Cejtin, Matthew Fluet, Suresh
   3  *    Jagannathan, and Stephen Weeks.
   4  *
   5  * MLton is released under a BSD-style license.
   6  * See the file MLton-LICENSE for details.
   7  *)
   8
   9 functor ObjptrTycon (S: OBJPTR_TYCON_STRUCTS): OBJPTR_TYCON =
  10 struct
  11
  12 open S
  13
  14 datatype t = T of {index: int ref}
  15
  16 local
  17    fun make f (T r) = f r
  18 in
  19    val index = ! o (make #index)
  20 end
  21
  22 local
  23    val c = Counter.new 0
  24 in
  25    fun new () = T {index = ref (Counter.next c)}
  26 end
  27
  28 fun setIndex (T {index = r}, i) = r := i
  29
  30 fun fromIndex i = T {index = ref i}
  31
  32 fun compare (opt, opt') = Int.compare (index opt, index opt')
  33
  34 fun equals (opt, opt') = index opt = index opt'
  35
  36 val op <= = fn (opt, opt') => index opt <= index opt'
  37
  38 fun toString (opt: t): string =
  39    concat ["opt_", Int.toString (index opt)]
  40
  41 val layout = Layout.str o toString
  42
  43 val stack = new ()
  44 val thread = new ()
  45 val weakGone = new ()
  46
  47 local
  48    val word8Vector = new ()
  49    val word16Vector = new ()
  50    val word32Vector = new ()
  51    val word64Vector = new ()
  52 in
  53    fun wordVector (b: Bits.t): t =
  54       case Bits.toInt b of
  55          8 => word8Vector
  56        | 16 => word16Vector
  57        | 32 => word32Vector
  58        | 64 => word64Vector
  59        | _ => Error.bug "ObjptrTycon.wordVector"
  60 end
  61
  62 end