Make getNameStr return original name of the Scop

[singam-sanjay]

Summary

The current implementation of Scop::getNameStr builds the name from the current boundaries of the Region, which might not be the original boundaries if getNameStr was called during or after applying the transformation to the Region.

Scop::getNameStr is altered to return the original name and Scop::getCurrentNameStr returns the name considering the current boundary of the Region.

[singam-sanjay]

This patch corrects the semantics of the accessor methods of the Scop class.

This patch is required by D33985, to prefix the name of the Scop to the name of the kernel, which currently manages without this with a hack.

I could even push the construction of std::string ScopNameForIR from GPUNodeBuilder in D33985 into Scop as a part of this patch.

Please share your thoughts.

[bollu]

@singam-sanjay I believe I commented on the changes in patch [D33985](http://reviews.llvm.org/D33985).

[grosser]

After we decided to number the scops, this patch is not needed any more, right? Should it be dropped?

[singam-sanjay]

Yes. I'll drop it.

include/polly/ScopInfo.h

public:
   ///
   /// These along with the function name can uniquely identify a Scop.
   ///
   /// @return std::pair whose first element is the entry name & second element
   ///         is the exit name.
   std::pair<std::string, std::string> getEntryExitStr() const;
 
   /// Get the name of this Scop.
-  std::string getNameStr() const;
+  std::string getNameStr() const { return name; }
+
+  /// Get the name of this Scop with it updated boundaries
+  std::string getCurrentNameStr() const;
 
   /// Get the constraint on parameter of this Scop.
   ///
   /// @return The constraint on parameter of this Scop.
   __isl_give isl_set *getContext() const;
   __isl_give isl_space *getParamSpace() const;
 
   /// Get the assumed context for this Scop.

lib/Analysis/ScopInfo.cpp

while (L) {
     L = L->getParentLoop();
   }
 
   return L ? (S.contains(L) ? L->getParentLoop() : L) : nullptr;
 }
 
 Scop::Scop(Region &R, ScalarEvolution &ScalarEvolution, LoopInfo &LI,
            ScopDetection::DetectionContext &DC)
-    : SE(&ScalarEvolution), R(R), name(R.getNameStr()), IsOptimized(false),
+    : SE(&ScalarEvolution), R(R), name(getCurrentNameStr()), IsOptimized(false),
       HasSingleExitEdge(R.getExitingBlock()), HasErrorBlock(false),
       MaxLoopDepth(0), CopyStmtsNum(0), DC(DC),
       IslCtx(isl_ctx_alloc(), isl_ctx_free), Context(nullptr),
       Affinator(this, LI), AssumedContext(nullptr), InvalidContext(nullptr),
       Schedule(nullptr) {
   if (IslOnErrorAbort)
     isl_options_set_on_error(getIslCtx(), ISL_ON_ERROR_ABORT);
   buildContext();
std::string Scop::getAssumedContextStr() const {
   assert(AssumedContext && "Assumed context not yet built");
   return stringFromIslObj(AssumedContext);
 }
 
 std::string Scop::getInvalidContextStr() const {
   return stringFromIslObj(InvalidContext);
 }
 
-std::string Scop::getNameStr() const {
+std::string Scop::getCurrentNameStr() const {
   std::string ExitName, EntryName;
   std::tie(EntryName, ExitName) = getEntryExitStr();
   return EntryName + "---" + ExitName;
 }
 
 std::pair<std::string, std::string> Scop::getEntryExitStr() const {
   std::string ExitName, EntryName;
   raw_string_ostream ExitStr(ExitName);