1 files changed, 13 insertions, 122 deletions

diff --git a/lib/CodeGen/CodeGenPGO.h b/lib/CodeGen/CodeGenPGO.h
index 431c850ef81e..de6f369fb351 100644
--- a/lib/CodeGen/CodeGenPGO.h
+++ b/lib/CodeGen/CodeGenPGO.h
@@ -24,10 +24,8 @@
 
 namespace clang {
 namespace CodeGen {
-class RegionCounter;
 
-/// Per-function PGO state. This class should generally not be used directly,
-/// but instead through the CodeGenFunction and RegionCounter types.
+/// Per-function PGO state.
 class CodeGenPGO {
 private:
   CodeGenModule &CGM;
@@ -62,37 +60,24 @@ public:
   /// exits.
   void setCurrentRegionCount(uint64_t Count) { CurrentRegionCount = Count; }
 
-  /// Indicate that the current region is never reached, and thus should have a
-  /// counter value of zero. This is important so that subsequent regions can
-  /// correctly track their parent counts.
-  void setCurrentRegionUnreachable() { setCurrentRegionCount(0); }
-
   /// Check if an execution count is known for a given statement. If so, return
   /// true and put the value in Count; else return false.
-  bool getStmtCount(const Stmt *S, uint64_t &Count) {
+  Optional<uint64_t> getStmtCount(const Stmt *S) {
     if (!StmtCountMap)
-      return false;
-    llvm::DenseMap<const Stmt*, uint64_t>::const_iterator
-      I = StmtCountMap->find(S);
+      return None;
+    auto I = StmtCountMap->find(S);
     if (I == StmtCountMap->end())
-      return false;
-    Count = I->second;
-    return true;
+      return None;
+    return I->second;
   }
 
   /// If the execution count for the current statement is known, record that
   /// as the current count.
   void setCurrentStmt(const Stmt *S) {
-    uint64_t Count;
-    if (getStmtCount(S, Count))
-      setCurrentRegionCount(Count);
+    if (auto Count = getStmtCount(S))
+      setCurrentRegionCount(*Count);
   }
 
-  /// Calculate branch weights appropriate for PGO data
-  llvm::MDNode *createBranchWeights(uint64_t TrueCount, uint64_t FalseCount);
-  llvm::MDNode *createBranchWeights(ArrayRef<uint64_t> Weights);
-  llvm::MDNode *createLoopWeights(const Stmt *Cond, RegionCounter &Cnt);
-
   /// Check if we need to emit coverage mapping for a given declaration
   void checkGlobalDecl(GlobalDecl GD);
   /// Assign counters to regions and configure them for PGO of a given
@@ -117,110 +102,16 @@ private:
   void emitCounterVariables();
   void emitCounterRegionMapping(const Decl *D);
 
-  /// Emit code to increment the counter at the given index
-  void emitCounterIncrement(CGBuilderTy &Builder, unsigned Counter);
+public:
+  void emitCounterIncrement(CGBuilderTy &Builder, const Stmt *S);
 
-  /// Return the region counter for the given statement. This should only be
-  /// called on statements that have a dedicated counter.
-  unsigned getRegionCounter(const Stmt *S) {
+  /// Return the region count for the counter at the given index.
+  uint64_t getRegionCount(const Stmt *S) {
     if (!RegionCounterMap)
       return 0;
-    return (*RegionCounterMap)[S];
-  }
-
-  /// Return the region count for the counter at the given index.
-  uint64_t getRegionCount(unsigned Counter) {
     if (!haveRegionCounts())
       return 0;
-    return RegionCounts[Counter];
-  }
-
-  friend class RegionCounter;
-};
-
-/// A counter for a particular region. This is the primary interface through
-/// which clients manage PGO counters and their values.
-class RegionCounter {
-  CodeGenPGO *PGO;
-  unsigned Counter;
-  uint64_t Count;
-  uint64_t ParentCount;
-  uint64_t RegionCount;
-  int64_t Adjust;
-
-  RegionCounter(CodeGenPGO &PGO, unsigned CounterIndex)
-    : PGO(&PGO), Counter(CounterIndex), Count(PGO.getRegionCount(Counter)),
-      ParentCount(PGO.getCurrentRegionCount()), Adjust(0) {}
-
-public:
-  RegionCounter(CodeGenPGO &PGO, const Stmt *S)
-    : PGO(&PGO), Counter(PGO.getRegionCounter(S)),
-      Count(PGO.getRegionCount(Counter)),
-      ParentCount(PGO.getCurrentRegionCount()), Adjust(0) {}
-
-  /// Get the value of the counter. In most cases this is the number of times
-  /// the region of the counter was entered, but for switch labels it's the
-  /// number of direct jumps to that label.
-  uint64_t getCount() const { return Count; }
-
-  /// Get the value of the counter with adjustments applied. Adjustments occur
-  /// when control enters or leaves the region abnormally; i.e., if there is a
-  /// jump to a label within the region, or if the function can return from
-  /// within the region. The adjusted count, then, is the value of the counter
-  /// at the end of the region.
-  uint64_t getAdjustedCount() const {
-    return Count + Adjust;
-  }
-
-  /// Get the value of the counter in this region's parent, i.e., the region
-  /// that was active when this region began. This is useful for deriving
-  /// counts in implicitly counted regions, like the false case of a condition
-  /// or the normal exits of a loop.
-  uint64_t getParentCount() const { return ParentCount; }
-
-  /// Activate the counter by emitting an increment and starting to track
-  /// adjustments. If AddIncomingFallThrough is true, the current region count
-  /// will be added to the counter for the purposes of tracking the region.
-  void beginRegion(CGBuilderTy &Builder, bool AddIncomingFallThrough=false) {
-    beginRegion(AddIncomingFallThrough);
-    PGO->emitCounterIncrement(Builder, Counter);
-  }
-  void beginRegion(bool AddIncomingFallThrough=false) {
-    RegionCount = Count;
-    if (AddIncomingFallThrough)
-      RegionCount += PGO->getCurrentRegionCount();
-    PGO->setCurrentRegionCount(RegionCount);
-  }
-
-  /// For counters on boolean branches, begins tracking adjustments for the
-  /// uncounted path.
-  void beginElseRegion() {
-    RegionCount = ParentCount - Count;
-    PGO->setCurrentRegionCount(RegionCount);
-  }
-
-  /// Reset the current region count.
-  void setCurrentRegionCount(uint64_t CurrentCount) {
-    RegionCount = CurrentCount;
-    PGO->setCurrentRegionCount(RegionCount);
-  }
-
-  /// Adjust for non-local control flow after emitting a subexpression or
-  /// substatement. This must be called to account for constructs such as gotos,
-  /// labels, and returns, so that we can ensure that our region's count is
-  /// correct in the code that follows.
-  void adjustForControlFlow() {
-    Adjust += PGO->getCurrentRegionCount() - RegionCount;
-    // Reset the region count in case this is called again later.
-    RegionCount = PGO->getCurrentRegionCount();
-  }
-
-  /// Commit all adjustments to the current region. If the region is a loop,
-  /// the LoopAdjust value should be the count of all the breaks and continues
-  /// from the loop, to compensate for those counts being deducted from the
-  /// adjustments for the body of the loop.
-  void applyAdjustmentsToRegion(uint64_t LoopAdjust) {
-    PGO->setCurrentRegionCount(ParentCount + Adjust + LoopAdjust);
+    return RegionCounts[(*RegionCounterMap)[S]];
   }
 };