1 files changed, 121 insertions, 0 deletions
diff --git a/contrib/llvm/tools/clang/lib/CodeGen/CodeGenPGO.h b/contrib/llvm/tools/clang/lib/CodeGen/CodeGenPGO.h
new file mode 100644
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--- /dev/null
+++ b/contrib/llvm/tools/clang/lib/CodeGen/CodeGenPGO.h
@@ -0,0 +1,121 @@
+//===--- CodeGenPGO.h - PGO Instrumentation for LLVM CodeGen ----*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Instrumentation-based profile-guided optimization
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_LIB_CODEGEN_CODEGENPGO_H
+#define LLVM_CLANG_LIB_CODEGEN_CODEGENPGO_H
+
+#include "CGBuilder.h"
+#include "CodeGenModule.h"
+#include "CodeGenTypes.h"
+#include "clang/Frontend/CodeGenOptions.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include <memory>
+
+namespace clang {
+namespace CodeGen {
+
+/// Per-function PGO state.
+class CodeGenPGO {
+private:
+  CodeGenModule &CGM;
+  std::string FuncName;
+  llvm::GlobalVariable *FuncNameVar;
+
+  unsigned NumRegionCounters;
+  uint64_t FunctionHash;
+  std::unique_ptr<llvm::DenseMap<const Stmt *, unsigned>> RegionCounterMap;
+  std::unique_ptr<llvm::DenseMap<const Stmt *, uint64_t>> StmtCountMap;
+  std::vector<uint64_t> RegionCounts;
+  uint64_t CurrentRegionCount;
+  /// \brief A flag that is set to true when this function doesn't need
+  /// to have coverage mapping data.
+  bool SkipCoverageMapping;
+
+public:
+  CodeGenPGO(CodeGenModule &CGM)
+      : CGM(CGM), NumRegionCounters(0), FunctionHash(0), CurrentRegionCount(0),
+        SkipCoverageMapping(false) {}
+
+  /// Whether or not we have PGO region data for the current function. This is
+  /// false both when we have no data at all and when our data has been
+  /// discarded.
+  bool haveRegionCounts() const { return !RegionCounts.empty(); }
+
+  /// Return the counter value of the current region.
+  uint64_t getCurrentRegionCount() const { return CurrentRegionCount; }
+
+  /// Set the counter value for the current region. This is used to keep track
+  /// of changes to the most recent counter from control flow and non-local
+  /// exits.
+  void setCurrentRegionCount(uint64_t Count) { CurrentRegionCount = Count; }
+
+  /// Check if an execution count is known for a given statement. If so, return
+  /// true and put the value in Count; else return false.
+  Optional<uint64_t> getStmtCount(const Stmt *S) {
+    if (!StmtCountMap)
+      return None;
+    auto I = StmtCountMap->find(S);
+    if (I == StmtCountMap->end())
+      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) {
+    if (auto Count = getStmtCount(S))
+      setCurrentRegionCount(*Count);
+  }
+
+  /// 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
+  /// function. Does nothing if instrumentation is not enabled and either
+  /// generates global variables or associates PGO data with each of the
+  /// counters depending on whether we are generating or using instrumentation.
+  void assignRegionCounters(const Decl *D, llvm::Function *Fn);
+  /// Emit a coverage mapping range with a counter zero
+  /// for an unused declaration.
+  void emitEmptyCounterMapping(const Decl *D, StringRef FuncName,
+                               llvm::GlobalValue::LinkageTypes Linkage);
+private:
+  void setFuncName(llvm::Function *Fn);
+  void setFuncName(StringRef Name, llvm::GlobalValue::LinkageTypes Linkage);
+  void createFuncNameVar(llvm::GlobalValue::LinkageTypes Linkage);
+  void mapRegionCounters(const Decl *D);
+  void computeRegionCounts(const Decl *D);
+  void applyFunctionAttributes(llvm::IndexedInstrProfReader *PGOReader,
+                               llvm::Function *Fn);
+  void loadRegionCounts(llvm::IndexedInstrProfReader *PGOReader,
+                        bool IsInMainFile);
+  void emitCounterVariables();
+  void emitCounterRegionMapping(const Decl *D);
+
+public:
+  void emitCounterIncrement(CGBuilderTy &Builder, const Stmt *S);
+
+  /// Return the region count for the counter at the given index.
+  uint64_t getRegionCount(const Stmt *S) {
+    if (!RegionCounterMap)
+      return 0;
+    if (!haveRegionCounts())
+      return 0;
+    return RegionCounts[(*RegionCounterMap)[S]];
+  }
+};
+
+}  // end namespace CodeGen
+}  // end namespace clang
+
+#endif