doc/guide/src/Flatten.adoc

   1 Flatten
   2 =======
   3
   4 <:Flatten:> is an optimization pass for the <:SSA:>
   5 <:IntermediateLanguage:>, invoked from <:SSASimplify:>.
   6
   7 == Description ==
   8
   9 This pass flattens arguments to <:SSA:> constructors, blocks, and
  10 functions.
  11
  12 If a tuple is explicitly available at all uses of a function
  13 (resp. block), then:
  14
  15 * The formals and call sites are changed so that the components of the
  16 tuple are passed.
  17
  18 * The tuple is reconstructed at the beginning of the body of the
  19 function (resp. block).
  20
  21 Similarly, if a tuple is explicitly available at all uses of a
  22 constructor, then:
  23
  24 * The constructor argument datatype is changed to flatten the tuple
  25 type.
  26
  27 * The tuple is passed flat at each `ConApp`.
  28
  29 * The tuple is reconstructed at each `Case` transfer target.
  30
  31 == Implementation ==
  32
  33 * <!ViewGitFile(mlton,master,mlton/ssa/flatten.fun)>
  34
  35 == Details and Notes ==
  36
  37 {empty}