[NFC][LLVM] Namespace cleanup in LoopFuse (llvm#163758)

Additionally, make the `Loop` argument to `printLoop` const.

Author: jurahul

llvm/include/llvm/Analysis/LoopInfo.h

@@ -617,7 +617,7 @@ class LLVM_ABI LoopInfoWrapperPass : public FunctionPass {
 };
 
 /// Function to print a loop's contents as LLVM's text IR assembly.
-LLVM_ABI void printLoop(Loop &L, raw_ostream &OS,
+LLVM_ABI void printLoop(const Loop &L, raw_ostream &OS,
                         const std::string &Banner = "");
 
 /// Find and return the loop attribute node for the attribute @p Name in

llvm/lib/Analysis/LoopInfo.cpp

@@ -986,8 +986,8 @@ PreservedAnalyses LoopPrinterPass::run(Function &F,
   return PreservedAnalyses::all();
 }
 
-void llvm::printLoop(Loop &L, raw_ostream &OS, const std::string &Banner) {
-
+void llvm::printLoop(const Loop &L, raw_ostream &OS,
+                     const std::string &Banner) {
   if (forcePrintModuleIR()) {
     // handling -print-module-scope
     OS << Banner << " (loop: ";

llvm/lib/Transforms/Scalar/LoopFuse.cpp

@@ -368,7 +368,7 @@ struct FusionCandidate {
     Valid = false;
   }
 
-  bool reportInvalidCandidate(llvm::Statistic &Stat) const {
+  bool reportInvalidCandidate(Statistic &Stat) const {
     using namespace ore;
     assert(L && Preheader && "Fusion candidate not initialized properly!");
 #if LLVM_ENABLE_STATS
@@ -445,6 +445,7 @@ struct FusionCandidateCompare {
         "No dominance relationship between these fusion candidates!");
   }
 };
+} // namespace
 
 using LoopVector = SmallVector<Loop *, 4>;
 
@@ -461,9 +462,15 @@ using LoopVector = SmallVector<Loop *, 4>;
 using FusionCandidateSet = std::set<FusionCandidate, FusionCandidateCompare>;
 using FusionCandidateCollection = SmallVector<FusionCandidateSet, 4>;
 
-#if !defined(NDEBUG)
-static llvm::raw_ostream &operator<<(llvm::raw_ostream &OS,
-                                     const FusionCandidate &FC) {
+#ifndef NDEBUG
+static void printLoopVector(const LoopVector &LV) {
+  dbgs() << "****************************\n";
+  for (const Loop *L : LV)
+    printLoop(*L, dbgs());
+  dbgs() << "****************************\n";
+}
+
+static raw_ostream &operator<<(raw_ostream &OS, const FusionCandidate &FC) {
   if (FC.isValid())
     OS << FC.Preheader->getName();
   else
@@ -472,8 +479,8 @@ static llvm::raw_ostream &operator<<(llvm::raw_ostream &OS,
   return OS;
 }
 
-static llvm::raw_ostream &operator<<(llvm::raw_ostream &OS,
-                                     const FusionCandidateSet &CandSet) {
+static raw_ostream &operator<<(raw_ostream &OS,
+                               const FusionCandidateSet &CandSet) {
   for (const FusionCandidate &FC : CandSet)
     OS << FC << '\n';
 
@@ -489,7 +496,9 @@ printFusionCandidates(const FusionCandidateCollection &FusionCandidates) {
     dbgs() << "****************************\n";
   }
 }
-#endif
+#endif // NDEBUG
+
+namespace {
 
 /// Collect all loops in function at the same nest level, starting at the
 /// outermost level.
@@ -550,15 +559,6 @@ struct LoopDepthTree {
   LoopsOnLevelTy LoopsOnLevel;
 };
 
-#ifndef NDEBUG
-static void printLoopVector(const LoopVector &LV) {
-  dbgs() << "****************************\n";
-  for (auto *L : LV)
-    printLoop(*L, dbgs());
-  dbgs() << "****************************\n";
-}
-#endif
-
 struct LoopFuser {
 private:
   // Sets of control flow equivalent fusion candidates for a given nest level.
@@ -1850,7 +1850,7 @@ struct LoopFuser {
   ///       <Cand1 Preheader> and <Cand2 Preheader>: <Stat Description>
   template <typename RemarkKind>
   void reportLoopFusion(const FusionCandidate &FC0, const FusionCandidate &FC1,
-                        llvm::Statistic &Stat) {
+                        Statistic &Stat) {
     assert(FC0.Preheader && FC1.Preheader &&
            "Expecting valid fusion candidates");
     using namespace ore;