[Polly][GSoC 2016] Draft of using new pass manager to cache/invalidate scop analysis in a function pass

[etherzhhb]

Summary

This is a proof of concept draft to use new pass manager inside a function pass to manage the scop analysis.

Ideally, we can call getScopAnalysis of ScopInfoWrapperPass to get any scop analysis.

[etherzhhb]

lib/Analysis/ScopInfo.cpp

4987

We also need to have a new-pass-manager-style pass to calculate Dependences from a Scop

[cs14mtech11017]

Thanks a lot. I will experiment with it.
Created a new pass to calculate dependences for a function D21105.
We can introduce similar changes over their.

include/polly/ScopInfo.h

 #include "polly/ScopDetection.h"
 #include "polly/Support/SCEVAffinator.h"
 
+#include "llvm/IR/PassManager.h"
 #include "llvm/ADT/MapVector.h"
 #include "llvm/Analysis/RegionPass.h"
 #include "isl/aff.h"

   void getAnalysisUsage(AnalysisUsage &AU) const override;
 };
 
+
 //===----------------------------------------------------------------------===//
 /// @brief The legacy pass manager's analysis pass to compute scop information
 ///        for the whole function.

 /// region pass manager.
 class ScopInfoWrapperPass : public FunctionPass {
 
+  /// New pass manager for Scop, we currently use it to cache/invalidate Scop at the
+  /// Function level.
+  using ScopAnalysisManager = llvm::AnalysisManager<Scop>;
+  ScopAnalysisManager SAM;
 public:
   using RegionToScopMapTy = DenseMap<Region *, std::unique_ptr<Scop>>;
   using iterator = RegionToScopMapTy::iterator;

   const_iterator begin() const { return RegionToScopMap.begin(); }
   const_iterator end() const { return RegionToScopMap.end(); }
 
+  template <typename T>
+  T getScopAnalysis(Region *R) {
+    auto *S = getScop(R);
+    assert(S && "Incorrect region!");
+    return SAM.getResult<T>(*R);
+  }
+
+  void invalidateScopAnalysis(Region *R) {
+    auto *S = getScop(R);
+    assert(S && "Incorrect region!");
+    SAM.invalidate(*S);
+  }
+
   /// @brief Calculate all the polyhedral scops for a given function.
   bool runOnFunction(Function &F) override;
 

lib/Analysis/ScopInfo.cpp

 
 void ScopInfoWrapperPass::print(raw_ostream &OS, const Module *) const {
   for (auto &It : RegionToScopMap) {
-    if (It.second)
+    if (It.second) {
       It.second->print(OS);
-    else
-      OS << "Invalid Scop!\n";
+      getScopAnalysis<Dependences>(*It.second);
+      continue;
+    }
+
+    OS << "Invalid Scop!\n";
   }
 }