digraph Memory {
  rankdir=LR;
  node [shape=box];
  M [label="Default memory"];
  X [label="Store x"];
  Y [label="Store y"];
  M -> X [color=blue]; M -> Y [color=green];
  M -> MemMerge [label="default"]; X -> MemMerge [label="x",color=blue];
  Y -> MemMerge [label="y",color=green]; MemMerge -> Return;
}