a simple introduction to this pass
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@6675 91177308-0d34-0410-b5e6-96231b3b80d8
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+The moduloScheduling pass includes two passes
+
+
+1. building graph
+The pass will build an instance of class ModuloSchedGraph for each loop-including basicblock in a function. The steps to build a graph:
+ a)build one node for each instruction in the basicblock
+ ---ModuloScheduGraph::buildNodesforBB()
+ b)add def-use edges
+ ---ModuloScheduGraph::addDefUseEdges()
+ c)add cd edges
+ ---ModuloScheduGraph::addCDEdges()
+ d)add mem dependency edges
+ ---ModuloScheduGraph::addMemEdges()
+ e)compute resource restriction II and recurrenct II
+ ---ModuloScheduGraph::computeResII()
+ ---ModuloScheduGraph::computeRecII()
+ f)compute each node's property, including ASAP,ALAP, Mov, Depth and Height.
+ ---ModuloScheduGraph::computeNodeProperty
+ g)sort all nodes
+ ---ModuloScheduGraph::orderNodes()
+
+
+2. compute schedule
+The second step is to compute a schule and replace the orginal basic block with three basicblocks: prelogue, kernelblock and epilog.
+
+ a)compute the schedule according the algorithm described in the paper
+ ---ModuloScheduling::computeSchedule()
+
+ b)replace the original basicblock.(to be done)
+ ---ModuloScheduling::constructPrologue();
+ ---ModuloScheduling::constructKernel();
+ ---ModuloScheduling::constructEpilogue();
+ These three functions are not working yet.