Reuse ScopStmt::isEmpty() function

Introduce a function getStmtForRegionNode() to the corresponding
ScopStmt of a RegionNode. We can use it to call the existing
ScopStmt::isEmpty() function instead of searching for accesses.

llvm-svn: 255465

2 files changed, 15 insertions, 7 deletions

diff --git a/polly/include/polly/ScopInfo.h b/polly/include/polly/ScopInfo.h
index d8c7c93c600..07ab57a6630 100644
--- a/polly/include/polly/ScopInfo.h
+++ b/polly/include/polly/ScopInfo.h
@@ -1575,6 +1575,11 @@ public:
   /// @brief Return the stmt for the given @p BB or nullptr if none.
   ScopStmt *getStmtForBasicBlock(BasicBlock *BB) const;
 
+  /// @brief Return the ScopStmt that represents @p RN; can return nullptr if
+  /// the RegionNode is not within the SCoP or has been removed due to
+  /// simplifications.
+  ScopStmt *getStmtForRegionNode(RegionNode *RN) const;
+
   /// @brief Return the number of statements in the SCoP.
   size_t getSize() const { return Stmts.size(); }
 
diff --git a/polly/lib/Analysis/ScopInfo.cpp b/polly/lib/Analysis/ScopInfo.cpp
index 7e236f6c20e..9d7a4339a92 100644
--- a/polly/lib/Analysis/ScopInfo.cpp
+++ b/polly/lib/Analysis/ScopInfo.cpp
@@ -3318,15 +3318,14 @@ ScalarEvolution *Scop::getSE() const { return SE; }
 
 bool Scop::isIgnored(RegionNode *RN) {
   BasicBlock *BB = getRegionNodeBasicBlock(RN);
+  ScopStmt *Stmt = getStmtForRegionNode(RN);
+
+  // If there is no stmt, then it already has been removed.
+  if (!Stmt)
+    return true;
 
   // Check if there are accesses contained.
-  bool ContainsAccesses = false;
-  if (!RN->isSubRegion())
-    ContainsAccesses = getAccessFunctions(BB);
-  else
-    for (BasicBlock *RBB : RN->getNodeAs<Region>()->blocks())
-      ContainsAccesses |= (getAccessFunctions(RBB) != nullptr);
-  if (!ContainsAccesses)
+  if (Stmt->isEmpty())
     return true;
 
   // Check for reachability via non-error blocks.
@@ -3491,6 +3490,10 @@ ScopStmt *Scop::getStmtForBasicBlock(BasicBlock *BB) const {
   return StmtMapIt->second;
 }
 
+ScopStmt *Scop::getStmtForRegionNode(RegionNode *RN) const {
+  return getStmtForBasicBlock(getRegionNodeBasicBlock(RN));
+}
+
 int Scop::getRelativeLoopDepth(const Loop *L) const {
   Loop *OuterLoop =
       L ? R.outermostLoopInRegion(const_cast<Loop *>(L)) : nullptr;