Pass to compute various statisics related to DSGraphs.
For now, this just computes the #indirect call sites and
the avg. #callees per indirect call site (actually it prints
both totals and the average is their ratio).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@4705 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/DataStructure/DataStructureStats.cpp b/lib/Analysis/DataStructure/DataStructureStats.cpp
new file mode 100644
index 0000000..1548bc5
--- /dev/null
+++ b/lib/Analysis/DataStructure/DataStructureStats.cpp
@@ -0,0 +1,86 @@
+//===- DSGraphStats.cpp - Various statistics for DS Graphs -----*- C++ -*--===//
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Analysis/DataStructure.h"
+#include "llvm/Analysis/DSGraph.h"
+#include "llvm/Function.h"
+#include "llvm/iOther.h"
+#include "llvm/Pass.h"
+#include "Support/Statistic.h"
+#include <vector>
+
+namespace {
+ Statistic<double> TotalNumCallees("totalcallees",
+ "Total number of callee functions at all indirect call sites");
+ Statistic<> NumIndirectCalls("numindirect",
+ "Total number of indirect call sites in the program");
+ Statistic<> NumPoolNodes("numpools",
+ "Number of allocation nodes that could be pool allocated");
+
+ class DSGraphStats: public FunctionPass {
+ void countCallees(const Function& F, const DSGraph& tdGraph);
+
+ public:
+ /// Driver functions to compute the Load/Store Dep. Graph per function.
+ bool runOnFunction(Function& F);
+
+ /// getAnalysisUsage - This modify nothing, and uses the Top-Down Graph.
+ void getAnalysisUsage(AnalysisUsage &AU) const {
+ AU.setPreservesAll();
+ AU.addRequired<TDDataStructures>();
+ }
+
+ /// Debugging support methods
+ void print(std::ostream &O) const { }
+ void dump() const;
+ };
+
+ static RegisterAnalysis<DSGraphStats> Z("dsstats", "DS Graph Statistics");
+}
+
+
+void DSGraphStats::countCallees(const Function& F,
+ const DSGraph& tdGraph)
+{
+ unsigned numIndirectCalls = 0, totalNumCallees = 0;
+
+ const std::vector<DSCallSite>& callSites = tdGraph.getFunctionCalls();
+ for (unsigned i=0, N = callSites.size(); i < N; ++i)
+ if (callSites[i].getCallInst().getCalledFunction() == NULL)
+ { // This is an indirect function call
+ std::vector<GlobalValue*> Callees =
+ callSites[i].getCallee().getNode()->getGlobals();
+ if (Callees.size() > 0)
+ {
+ totalNumCallees += Callees.size();
+ ++numIndirectCalls;
+ }
+#ifndef NDEBUG
+ else
+ std::cerr << "WARNING: No callee in Function " << F.getName()
+ << "at call:\n" << callSites[i].getCallInst();
+#endif
+ }
+
+ TotalNumCallees += totalNumCallees;
+ NumIndirectCalls += numIndirectCalls;
+
+ std::cout << " In function " << F.getName() << " : "
+ << (double) (numIndirectCalls == 0? 0.0
+ : (totalNumCallees / (double) numIndirectCalls))
+ << " avg. callees per indirect call\n";
+}
+
+
+bool DSGraphStats::runOnFunction(Function& F)
+{
+ const DSGraph& tdGraph = getAnalysis<TDDataStructures>().getDSGraph(F);
+ countCallees(F, tdGraph);
+ return true;
+}
+
+void DSGraphStats::dump() const
+{
+ this->print(std::cerr);
+}