3 files changed, 56 insertions, 23 deletions

diff --git a/clang/lib/CodeGen/CodeGenFunction.cpp b/clang/lib/CodeGen/CodeGenFunction.cpp
index d0f1cb6b258..975ae6cb46b 100644
--- a/clang/lib/CodeGen/CodeGenFunction.cpp
+++ b/clang/lib/CodeGen/CodeGenFunction.cpp
@@ -589,15 +589,6 @@ void CodeGenFunction::StartFunction(GlobalDecl GD,
   if (CGM.getCodeGenOpts().InstrumentForProfiling)
     EmitMCountInstrumentation();
 
-  if (CGM.getPGOData() && D) {
-    // Turn on InlineHint attribute for hot functions.
-    if (CGM.getPGOData()->isHotFunction(CGM.getMangledName(GD)))
-      Fn->addFnAttr(llvm::Attribute::InlineHint);
-    // Turn on Cold attribute for cold functions.
-    else if (CGM.getPGOData()->isColdFunction(CGM.getMangledName(GD)))
-      Fn->addFnAttr(llvm::Attribute::Cold);
-  }
-
   if (RetTy->isVoidType()) {
     // Void type; nothing to return.
     ReturnValue = 0;
@@ -770,7 +761,7 @@ void CodeGenFunction::GenerateCode(GlobalDecl GD, llvm::Function *Fn,
   StartFunction(GD, ResTy, Fn, FnInfo, Args, BodyRange.getBegin());
 
   // Generate the body of the function.
-  PGO.assignRegionCounters(GD.getDecl(), CGM.getMangledName(GD));
+  PGO.assignRegionCounters(GD.getDecl(), CurFn);
   if (isa<CXXDestructorDecl>(FD))
     EmitDestructorBody(Args);
   else if (isa<CXXConstructorDecl>(FD))
@@ -831,7 +822,7 @@ void CodeGenFunction::GenerateCode(GlobalDecl GD, llvm::Function *Fn,
   if (!CurFn->doesNotThrow())
     TryMarkNoThrow(CurFn);
 
-  PGO.emitWriteoutFunction(CGM.getMangledName(CurGD));
+  PGO.emitWriteoutFunction();
   PGO.destroyRegionCounters();
 }
 
diff --git a/clang/lib/CodeGen/CodeGenPGO.cpp b/clang/lib/CodeGen/CodeGenPGO.cpp
index 658fb2c9986..6678c37929b 100644
--- a/clang/lib/CodeGen/CodeGenPGO.cpp
+++ b/clang/lib/CodeGen/CodeGenPGO.cpp
@@ -161,7 +161,32 @@ bool PGOProfileData::getFunctionCounts(StringRef FuncName,
   return false;
 }
 
-void CodeGenPGO::emitWriteoutFunction(StringRef Name) {
+void CodeGenPGO::setFuncName(llvm::Function *Fn) {
+  StringRef Func = Fn->getName();
+
+  // Function names may be prefixed with a binary '1' to indicate
+  // that the backend should not modify the symbols due to any platform
+  // naming convention. Do not include that '1' in the PGO profile name.
+  if (Func[0] == '\1')
+    Func = Func.substr(1);
+
+  if (!Fn->hasLocalLinkage()) {
+    FuncName = new std::string(Func);
+    return;
+  }
+
+  // For local symbols, prepend the main file name to distinguish them.
+  // Do not include the full path in the file name since there's no guarantee
+  // that it will stay the same, e.g., if the files are checked out from
+  // version control in different locations.
+  FuncName = new std::string(CGM.getCodeGenOpts().MainFileName);
+  if (FuncName->empty())
+    FuncName->assign("<unknown>");
+  FuncName->append(":");
+  FuncName->append(Func);
+}
+
+void CodeGenPGO::emitWriteoutFunction() {
   if (!CGM.getCodeGenOpts().ProfileInstrGenerate)
     return;
 
@@ -206,7 +231,7 @@ void CodeGenPGO::emitWriteoutFunction(StringRef Name) {
     CGM.getModule().getOrInsertFunction("llvm_pgo_emit", FTy);
 
   llvm::Constant *NameString =
-    CGM.GetAddrOfConstantCString(Name, "__llvm_pgo_name");
+    CGM.GetAddrOfConstantCString(getFuncName(), "__llvm_pgo_name");
   NameString = llvm::ConstantExpr::getBitCast(NameString, Int8PtrTy);
   PGOBuilder.CreateCall3(EmitFunc, NameString,
                          PGOBuilder.getInt32(NumRegionCounters),
@@ -727,19 +752,27 @@ namespace {
   };
 }
 
-void CodeGenPGO::assignRegionCounters(const Decl *D, StringRef Name) {
+void CodeGenPGO::assignRegionCounters(const Decl *D, llvm::Function *Fn) {
   bool InstrumentRegions = CGM.getCodeGenOpts().ProfileInstrGenerate;
   PGOProfileData *PGOData = CGM.getPGOData();
   if (!InstrumentRegions && !PGOData)
     return;
   if (!D)
     return;
+  setFuncName(Fn);
   mapRegionCounters(D);
   if (InstrumentRegions)
     emitCounterVariables();
   if (PGOData) {
-    loadRegionCounts(Name, PGOData);
+    loadRegionCounts(PGOData);
     computeRegionCounts(D);
+
+    // Turn on InlineHint attribute for hot functions.
+    if (PGOData->isHotFunction(getFuncName()))
+      Fn->addFnAttr(llvm::Attribute::InlineHint);
+    // Turn on Cold attribute for cold functions.
+    else if (PGOData->isColdFunction(getFuncName()))
+      Fn->addFnAttr(llvm::Attribute::Cold);
   }
 }
 
@@ -779,13 +812,13 @@ void CodeGenPGO::emitCounterIncrement(CGBuilderTy &Builder, unsigned Counter) {
   Builder.CreateStore(Count, Addr);
 }
 
-void CodeGenPGO::loadRegionCounts(StringRef Name, PGOProfileData *PGOData) {
+void CodeGenPGO::loadRegionCounts(PGOProfileData *PGOData) {
   // For now, ignore the counts from the PGO data file only if the number of
   // counters does not match. This could be tightened down in the future to
   // ignore counts when the input changes in various ways, e.g., by comparing a
   // hash value based on some characteristics of the input.
   RegionCounts = new std::vector<uint64_t>();
-  if (PGOData->getFunctionCounts(Name, *RegionCounts) ||
+  if (PGOData->getFunctionCounts(getFuncName(), *RegionCounts) ||
       RegionCounts->size() != NumRegionCounters) {
     delete RegionCounts;
     RegionCounts = 0;
diff --git a/clang/lib/CodeGen/CodeGenPGO.h b/clang/lib/CodeGen/CodeGenPGO.h
index c9c0e8b004c..0fc570ad9cd 100644
--- a/clang/lib/CodeGen/CodeGenPGO.h
+++ b/clang/lib/CodeGen/CodeGenPGO.h
@@ -56,6 +56,7 @@ public:
 class CodeGenPGO {
 private:
   CodeGenModule &CGM;
+  std::string *FuncName;
 
   unsigned NumRegionCounters;
   llvm::GlobalVariable *RegionCounters;
@@ -66,15 +67,22 @@ private:
 
 public:
   CodeGenPGO(CodeGenModule &CGM)
-    : CGM(CGM), NumRegionCounters(0), RegionCounters(0), RegionCounterMap(0),
-      StmtCountMap(0), RegionCounts(0), CurrentRegionCount(0) {}
-  ~CodeGenPGO() {}
+    : CGM(CGM), FuncName(0), NumRegionCounters(0), RegionCounters(0),
+      RegionCounterMap(0), StmtCountMap(0), RegionCounts(0),
+      CurrentRegionCount(0) {}
+  ~CodeGenPGO() {
+    if (FuncName) delete FuncName;
+  }
 
   /// 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 != 0; }
 
+  /// Get the string used to identify this function in the profile data.
+  /// For functions with local linkage, this includes the main file name.
+  const StringRef getFuncName() const { return StringRef(*FuncName); }
+
   /// Return the counter value of the current region.
   uint64_t getCurrentRegionCount() const { return CurrentRegionCount; }
 
@@ -118,9 +126,9 @@ public:
   /// 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, StringRef Name);
+  void assignRegionCounters(const Decl *D, llvm::Function *Fn);
   /// Emit code to write counts for a given function to disk, if necessary.
-  void emitWriteoutFunction(StringRef Name);
+  void emitWriteoutFunction();
   /// Clean up region counter state. Must be called if assignRegionCounters is
   /// used.
   void destroyRegionCounters();
@@ -129,9 +137,10 @@ public:
   static llvm::Function *emitInitialization(CodeGenModule &CGM);
 
 private:
+  void setFuncName(llvm::Function *Fn);
   void mapRegionCounters(const Decl *D);
   void computeRegionCounts(const Decl *D);
-  void loadRegionCounts(StringRef Name, PGOProfileData *PGOData);
+  void loadRegionCounts(PGOProfileData *PGOData);
   void emitCounterVariables();
 
   /// Emit code to increment the counter at the given index