doc/guide/src/PolyHash.adoc

   1 PolyHash
   2 ========
   3
   4 <:PolyHash:> is an optimization pass for the <:SSA:>
   5 <:IntermediateLanguage:>, invoked from <:SSASimplify:>.
   6
   7 == Description ==
   8
   9 This pass implements polymorphic, structural hashing.
  10
  11 == Implementation ==
  12
  13 * <!ViewGitFile(mlton,master,mlton/ssa/poly-hash.fun)>
  14
  15 == Details and Notes ==
  16
  17 For each datatype, tycon, and vector type, it builds and equality
  18 function and translates calls to `MLton_hash` into calls to that
  19 function.
  20
  21 For tuples, it does the equality test inline; i.e., it does not create
  22 a separate equality function for each tuple type.
  23
  24 All equality functions are created only if necessary, i.e., if
  25 equality is actually used at a type.