lib/CodeGen/ModuloScheduling/README

   1 The modulo scheduling pass impliment modulo scheduling for llvm instruction. It includes two passes
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   4 1. building graph
   5 The pass will build an instance of class ModuloSchedGraph for each loop-including basicblock in a function. The steps to build a graph:
   6         a)build one node for each instruction in the basicblock
   7                 ---ModuloScheduGraph::buildNodesforBB()
   8         b)add def-use edges
   9                 ---ModuloScheduGraph::addDefUseEdges()
  10         c)add cd edges
  11                 ---ModuloScheduGraph::addCDEdges()
  12         d)add mem dependency edges
  13                 ---ModuloScheduGraph::addMemEdges()
  14         e)compute resource restriction II and recurrenct II
  15                 ---ModuloScheduGraph::computeResII()
  16                 ---ModuloScheduGraph::computeRecII()
  17         f)compute each node's property, including ASAP,ALAP, Mov, Depth and Height.
  18                 ---ModuloScheduGraph::computeNodeProperty
  19         g)sort all nodes
  20                 ---ModuloScheduGraph::orderNodes()
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  23 2. compute schedule
  24 The second step is to compute a schule and replace the orginal basic block with three basicblocks: prelogue, kernelblock and epilog.
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  26         a)compute the schedule according the algorithm described in the paper
  27                 ---ModuloScheduling::computeSchedule()
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  29         b)replace the original basicblock.(to be done)
  30                 ---ModuloScheduling::constructPrologue();
  31                 ---ModuloScheduling::constructKernel();
  32                 ---ModuloScheduling::constructEpilogue();
  33         These three functions are not working yet.