1 files changed, 79 insertions, 15 deletions

diff --git a/include/llvm/Analysis/BranchProbabilityInfo.h b/include/llvm/Analysis/BranchProbabilityInfo.h
index cfdf218491bdb..6434ba962ebc1 100644
--- a/include/llvm/Analysis/BranchProbabilityInfo.h
+++ b/include/llvm/Analysis/BranchProbabilityInfo.h
@@ -15,8 +15,11 @@
 #define LLVM_ANALYSIS_BRANCHPROBABILITYINFO_H
 
 #include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/DenseSet.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/IR/CFG.h"
+#include "llvm/IR/PassManager.h"
+#include "llvm/IR/ValueHandle.h"
 #include "llvm/InitializePasses.h"
 #include "llvm/Pass.h"
 #include "llvm/Support/BranchProbability.h"
@@ -40,7 +43,22 @@ class raw_ostream;
 class BranchProbabilityInfo {
 public:
   BranchProbabilityInfo() {}
-  BranchProbabilityInfo(Function &F, const LoopInfo &LI) { calculate(F, LI); }
+  BranchProbabilityInfo(const Function &F, const LoopInfo &LI) {
+    calculate(F, LI);
+  }
+
+  BranchProbabilityInfo(BranchProbabilityInfo &&Arg)
+      : Probs(std::move(Arg.Probs)), LastF(Arg.LastF),
+        PostDominatedByUnreachable(std::move(Arg.PostDominatedByUnreachable)),
+        PostDominatedByColdCall(std::move(Arg.PostDominatedByColdCall)) {}
+
+  BranchProbabilityInfo &operator=(BranchProbabilityInfo &&RHS) {
+    releaseMemory();
+    Probs = std::move(RHS.Probs);
+    PostDominatedByColdCall = std::move(RHS.PostDominatedByColdCall);
+    PostDominatedByUnreachable = std::move(RHS.PostDominatedByUnreachable);
+    return *this;
+  }
 
   void releaseMemory();
 
@@ -74,7 +92,7 @@ public:
   ///
   /// Given a basic block, look through its successors and if one exists for
   /// which \see isEdgeHot would return true, return that successor block.
-  BasicBlock *getHotSucc(BasicBlock *BB) const;
+  const BasicBlock *getHotSucc(const BasicBlock *BB) const;
 
   /// \brief Print an edge's probability.
   ///
@@ -98,9 +116,31 @@ public:
     return IsLikely ? LikelyProb : LikelyProb.getCompl();
   }
 
-  void calculate(Function &F, const LoopInfo& LI);
+  void calculate(const Function &F, const LoopInfo &LI);
+
+  /// Forget analysis results for the given basic block.
+  void eraseBlock(const BasicBlock *BB);
 
 private:
+  void operator=(const BranchProbabilityInfo &) = delete;
+  BranchProbabilityInfo(const BranchProbabilityInfo &) = delete;
+
+  // We need to store CallbackVH's in order to correctly handle basic block
+  // removal.
+  class BasicBlockCallbackVH final : public CallbackVH {
+    BranchProbabilityInfo *BPI;
+    void deleted() override {
+      assert(BPI != nullptr);
+      BPI->eraseBlock(cast<BasicBlock>(getValPtr()));
+      BPI->Handles.erase(*this);
+    }
+
+  public:
+    BasicBlockCallbackVH(const Value *V, BranchProbabilityInfo *BPI=nullptr)
+        : CallbackVH(const_cast<Value *>(V)), BPI(BPI) {}
+  };
+  DenseSet<BasicBlockCallbackVH, DenseMapInfo<Value*>> Handles;
+
   // Since we allow duplicate edges from one basic block to another, we use
   // a pair (PredBlock and an index in the successors) to specify an edge.
   typedef std::pair<const BasicBlock *, unsigned> Edge;
@@ -116,22 +156,46 @@ private:
   DenseMap<Edge, BranchProbability> Probs;
 
   /// \brief Track the last function we run over for printing.
-  Function *LastF;
+  const Function *LastF;
 
   /// \brief Track the set of blocks directly succeeded by a returning block.
-  SmallPtrSet<BasicBlock *, 16> PostDominatedByUnreachable;
+  SmallPtrSet<const BasicBlock *, 16> PostDominatedByUnreachable;
 
   /// \brief Track the set of blocks that always lead to a cold call.
-  SmallPtrSet<BasicBlock *, 16> PostDominatedByColdCall;
-
-  bool calcUnreachableHeuristics(BasicBlock *BB);
-  bool calcMetadataWeights(BasicBlock *BB);
-  bool calcColdCallHeuristics(BasicBlock *BB);
-  bool calcPointerHeuristics(BasicBlock *BB);
-  bool calcLoopBranchHeuristics(BasicBlock *BB, const LoopInfo &LI);
-  bool calcZeroHeuristics(BasicBlock *BB);
-  bool calcFloatingPointHeuristics(BasicBlock *BB);
-  bool calcInvokeHeuristics(BasicBlock *BB);
+  SmallPtrSet<const BasicBlock *, 16> PostDominatedByColdCall;
+
+  bool calcUnreachableHeuristics(const BasicBlock *BB);
+  bool calcMetadataWeights(const BasicBlock *BB);
+  bool calcColdCallHeuristics(const BasicBlock *BB);
+  bool calcPointerHeuristics(const BasicBlock *BB);
+  bool calcLoopBranchHeuristics(const BasicBlock *BB, const LoopInfo &LI);
+  bool calcZeroHeuristics(const BasicBlock *BB);
+  bool calcFloatingPointHeuristics(const BasicBlock *BB);
+  bool calcInvokeHeuristics(const BasicBlock *BB);
+};
+
+/// \brief Analysis pass which computes \c BranchProbabilityInfo.
+class BranchProbabilityAnalysis
+    : public AnalysisInfoMixin<BranchProbabilityAnalysis> {
+  friend AnalysisInfoMixin<BranchProbabilityAnalysis>;
+  static char PassID;
+
+public:
+  /// \brief Provide the result typedef for this analysis pass.
+  typedef BranchProbabilityInfo Result;
+
+  /// \brief Run the analysis pass over a function and produce BPI.
+  BranchProbabilityInfo run(Function &F, AnalysisManager<Function> &AM);
+};
+
+/// \brief Printer pass for the \c BranchProbabilityAnalysis results.
+class BranchProbabilityPrinterPass
+    : public PassInfoMixin<BranchProbabilityPrinterPass> {
+  raw_ostream &OS;
+
+public:
+  explicit BranchProbabilityPrinterPass(raw_ostream &OS) : OS(OS) {}
+  PreservedAnalyses run(Function &F, AnalysisManager<Function> &AM);
 };
 
 /// \brief Legacy analysis pass which computes \c BranchProbabilityInfo.