From 254e289d45337ec1da930ef93b4b1dd92f791153 Mon Sep 17 00:00:00 2001
From: Lei Zhang <antiagainst@google.com>
Date: Mon, 26 Apr 2021 18:27:41 -0400
Subject: [PATCH] Revert "[ADT] Remove StatisticBase and make NoopStatistic
 empty"

This reverts commit b5403117814a7c39b944839e10492493f2ceb4ac
because it breaks MLIR build:

https://buildkite.com/mlir/mlir-core/builds/13299#ad0f8901-dfa4-43cf-81b8-7940e2c6c15b
---
 llvm/include/llvm/ADT/Statistic.h       | 30 +++++++++++++++++-------------
 llvm/lib/Transforms/Scalar/LoopFuse.cpp |  4 ----
 2 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/llvm/include/llvm/ADT/Statistic.h b/llvm/include/llvm/ADT/Statistic.h
index de7dabc..aa338cc 100644
--- a/llvm/include/llvm/ADT/Statistic.h
+++ b/llvm/include/llvm/ADT/Statistic.h
@@ -46,22 +46,27 @@ class raw_ostream;
 class raw_fd_ostream;
 class StringRef;
 
-class TrackingStatistic {
+class StatisticBase {
 public:
-  const char *const DebugType;
-  const char *const Name;
-  const char *const Desc;
+  const char *DebugType;
+  const char *Name;
+  const char *Desc;
 
-  std::atomic<unsigned> Value;
-  std::atomic<bool> Initialized;
-
-  TrackingStatistic(const char *DebugType, const char *Name, const char *Desc)
-      : DebugType(DebugType), Name(Name), Desc(Desc), Value(0),
-        Initialized(false) {}
+  StatisticBase(const char *DebugType, const char *Name, const char *Desc)
+      : DebugType(DebugType), Name(Name), Desc(Desc) {}
 
   const char *getDebugType() const { return DebugType; }
   const char *getName() const { return Name; }
   const char *getDesc() const { return Desc; }
+};
+
+class TrackingStatistic : public StatisticBase {
+public:
+  std::atomic<unsigned> Value;
+  std::atomic<bool> Initialized;
+
+  TrackingStatistic(const char *DebugType, const char *Name, const char *Desc)
+      : StatisticBase(DebugType, Name, Desc), Value(0), Initialized(false) {}
 
   unsigned getValue() const { return Value.load(std::memory_order_relaxed); }
 
@@ -127,10 +132,9 @@ protected:
   void RegisterStatistic();
 };
 
-class NoopStatistic {
+class NoopStatistic : public StatisticBase {
 public:
-  NoopStatistic(const char * /*DebugType*/, const char * /*Name*/,
-                const char * /*Desc*/) {}
+  using StatisticBase::StatisticBase;
 
   unsigned getValue() const { return 0; }
 
diff --git a/llvm/lib/Transforms/Scalar/LoopFuse.cpp b/llvm/lib/Transforms/Scalar/LoopFuse.cpp
index ca19913..63f02d0 100644
--- a/llvm/lib/Transforms/Scalar/LoopFuse.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopFuse.cpp
@@ -372,13 +372,11 @@ private:
   bool reportInvalidCandidate(llvm::Statistic &Stat) const {
     using namespace ore;
     assert(L && Preheader && "Fusion candidate not initialized properly!");
-#if LLVM_ENABLE_STATS
     ++Stat;
     ORE.emit(OptimizationRemarkAnalysis(DEBUG_TYPE, Stat.getName(),
                                         L->getStartLoc(), Preheader)
              << "[" << Preheader->getParent()->getName() << "]: "
              << "Loop is not a candidate for fusion: " << Stat.getDesc());
-#endif
     return false;
   }
 };
@@ -1535,7 +1533,6 @@ private:
     assert(FC0.Preheader && FC1.Preheader &&
            "Expecting valid fusion candidates");
     using namespace ore;
-#if LLVM_ENABLE_STATS
     ++Stat;
     ORE.emit(RemarkKind(DEBUG_TYPE, Stat.getName(), FC0.L->getStartLoc(),
                         FC0.Preheader)
@@ -1543,7 +1540,6 @@ private:
              << "]: " << NV("Cand1", StringRef(FC0.Preheader->getName()))
              << " and " << NV("Cand2", StringRef(FC1.Preheader->getName()))
              << ": " << Stat.getDesc());
-#endif
   }
 
   /// Fuse two guarded fusion candidates, creating a new fused loop.
-- 
2.7.4