Index: include/llvm/Transforms/InstrProfiling.h
===================================================================
--- include/llvm/Transforms/InstrProfiling.h
+++ include/llvm/Transforms/InstrProfiling.h
@@ -100,23 +100,23 @@
   GlobalVariable *getOrCreateRegionCounters(InstrProfIncrementInst *Inc);
 
   /// Emit the section with compressed function names.
-  void emitNameData();
+  bool emitNameData();
 
   /// Emit value nodes section for value profiling.
-  void emitVNodes();
+  bool emitVNodes();
 
   /// Emit runtime registration functions for each profile data variable.
-  void emitRegistration();
+  bool emitRegistration();
 
   /// Emit the necessary plumbing to pull in the runtime initialization.
-  void emitRuntimeHook();
+  bool emitRuntimeHook();
 
   /// Add uses of our data variables and runtime hook.
-  void emitUses();
+  bool emitUses();
 
   /// Create a static initializer for our data, on platforms that need it,
   /// and for any profile output file that was specified.
-  void emitInitialization();
+  bool emitInitialization();
 };
 
 } // end namespace llvm
Index: lib/Transforms/Instrumentation/InstrProfiling.cpp
===================================================================
--- lib/Transforms/Instrumentation/InstrProfiling.cpp
+++ lib/Transforms/Instrumentation/InstrProfiling.cpp
@@ -430,32 +430,8 @@
   }
 }
 
-/// Check if the module contains uses of any profiling intrinsics.
-static bool containsProfilingIntrinsics(Module &M) {
-  if (auto *F = M.getFunction(
-          Intrinsic::getName(llvm::Intrinsic::instrprof_increment)))
-    if (!F->use_empty())
-      return true;
-  if (auto *F = M.getFunction(
-          Intrinsic::getName(llvm::Intrinsic::instrprof_increment_step)))
-    if (!F->use_empty())
-      return true;
-  if (auto *F = M.getFunction(
-          Intrinsic::getName(llvm::Intrinsic::instrprof_value_profile)))
-    if (!F->use_empty())
-      return true;
-  return false;
-}
-
 bool InstrProfiling::run(Module &M, const TargetLibraryInfo &TLI) {
-  // Improve compile time by avoiding linear scans when there is no work.
-  GlobalVariable *CoverageNamesVar =
-      M.getNamedGlobal(getCoverageUnusedNamesVarName());
-  if (!containsProfilingIntrinsics(M) && !CoverageNamesVar)
-    return false;
-
   bool MadeChange = false;
-
   this->M = &M;
   this->TLI = &TLI;
   NamesVar = nullptr;
@@ -487,21 +463,19 @@
   for (Function &F : M)
     MadeChange |= lowerIntrinsics(&F);
 
-  if (CoverageNamesVar) {
+  if (GlobalVariable *CoverageNamesVar =
+          M.getNamedGlobal(getCoverageUnusedNamesVarName())) {
     lowerCoverageData(CoverageNamesVar);
     MadeChange = true;
   }
 
-  if (!MadeChange)
-    return false;
-
-  emitVNodes();
-  emitNameData();
-  emitRegistration();
-  emitRuntimeHook();
-  emitUses();
-  emitInitialization();
-  return true;
+  MadeChange |= emitVNodes();
+  MadeChange |= emitNameData();
+  MadeChange |= emitRegistration();
+  MadeChange |= emitRuntimeHook();
+  MadeChange |= emitUses();
+  MadeChange |= emitInitialization();
+  return MadeChange;
 }
 
 static Constant *getOrInsertValueProfilingCall(Module &M,
@@ -801,15 +775,15 @@
   return CounterPtr;
 }
 
-void InstrProfiling::emitVNodes() {
+bool InstrProfiling::emitVNodes() {
   if (!ValueProfileStaticAlloc)
-    return;
+    return false;
 
   // For now only support this on platforms that do
   // not require runtime registration to discover
   // named section start/end.
   if (needsRuntimeRegistrationOfSectionRange(*M))
-    return;
+    return false;
 
   size_t TotalNS = 0;
   for (auto &PD : ProfileDataMap) {
@@ -818,7 +792,7 @@
   }
 
   if (!TotalNS)
-    return;
+    return false;
 
   uint64_t NumCounters = TotalNS * NumCountersPerValueSite;
 // Heuristic for small programs with very few total value sites.
@@ -846,13 +820,14 @@
   VNodesVar->setSection(
       getInstrProfSectionName(IPSK_vnodes, TT.getObjectFormat()));
   UsedVars.push_back(VNodesVar);
+  return true;
 }
 
-void InstrProfiling::emitNameData() {
+bool InstrProfiling::emitNameData() {
   std::string UncompressedData;
 
   if (ReferencedNames.empty())
-    return;
+    return false;
 
   std::string CompressedNameStr;
   if (Error E = collectPGOFuncNameStrings(ReferencedNames, CompressedNameStr,
@@ -873,11 +848,12 @@
 
   for (auto *NamePtr : ReferencedNames)
     NamePtr->eraseFromParent();
+  return true;
 }
 
-void InstrProfiling::emitRegistration() {
+bool InstrProfiling::emitRegistration() {
   if (!needsRuntimeRegistrationOfSectionRange(*M))
-    return;
+    return false;
 
   // Construct the function.
   auto *VoidTy = Type::getVoidTy(M->getContext());
@@ -912,17 +888,18 @@
   }
 
   IRB.CreateRetVoid();
+  return true;
 }
 
-void InstrProfiling::emitRuntimeHook() {
+bool InstrProfiling::emitRuntimeHook() {
   // We expect the linker to be invoked with -u<hook_var> flag for linux,
   // for which case there is no need to emit the user function.
   if (Triple(M->getTargetTriple()).isOSLinux())
-    return;
+    return false;
 
   // If the module's provided its own runtime, we don't need to do anything.
   if (M->getGlobalVariable(getInstrProfRuntimeHookVarName()))
-    return;
+    return false;
 
   // Declare an external variable that will pull in the runtime initialization.
   auto *Int32Ty = Type::getInt32Ty(M->getContext());
@@ -947,14 +924,19 @@
 
   // Mark the user variable as used so that it isn't stripped out.
   UsedVars.push_back(User);
+  return true;
 }
 
-void InstrProfiling::emitUses() {
-  if (!UsedVars.empty())
+bool InstrProfiling::emitUses() {
+  if (!UsedVars.empty()) {
     appendToUsed(*M, UsedVars);
+    return true;
+  }
+  return false;
 }
 
-void InstrProfiling::emitInitialization() {
+bool InstrProfiling::emitInitialization() {
+  bool MadeChange = false;
   StringRef InstrProfileOutput = Options.InstrProfileOutput;
 
   if (!InstrProfileOutput.empty()) {
@@ -969,11 +951,12 @@
       ProfileNameVar->setComdat(M->getOrInsertComdat(
           StringRef(INSTR_PROF_QUOTE(INSTR_PROF_PROFILE_NAME_VAR))));
     }
+    MadeChange = true;
   }
 
   Constant *RegisterF = M->getFunction(getInstrProfRegFuncsName());
   if (!RegisterF)
-    return;
+    return MadeChange;
 
   // Create the initialization function.
   auto *VoidTy = Type::getVoidTy(M->getContext());
@@ -992,4 +975,6 @@
   IRB.CreateRetVoid();
 
   appendToGlobalCtors(*M, F, 0);
+  MadeChange = true;
+  return MadeChange;
 }
Index: test/Instrumentation/InstrProfiling/early-exit.ll
===================================================================
--- test/Instrumentation/InstrProfiling/early-exit.ll
+++ /dev/null
@@ -1,15 +0,0 @@
-; RUN: opt < %s -instrprof -S | FileCheck %s
-
-target triple = "x86_64-apple-macosx10.10.0"
-
-declare void @llvm.instrprof.increment(i8*, i64, i32, i32)
-
-declare void @llvm.instrprof.increment.step(i8*, i64, i32, i32, i64)
-
-@__profn_foo = hidden constant [3 x i8] c"foo"
-
-define void @foo() {
-; CHECK: @__profc_foo = hidden global [1 x i64] zeroinitializer, section "__DATA,__llvm_prf_cnts", align 8
-  call void @llvm.instrprof.increment.step(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @__profn_foo, i32 0, i32 0), i64 0, i32 1, i32 0, i64 0)
-  ret void
-}
Index: test/Instrumentation/InstrProfiling/no-counters.ll
===================================================================
--- test/Instrumentation/InstrProfiling/no-counters.ll
+++ test/Instrumentation/InstrProfiling/no-counters.ll
@@ -1,10 +1,10 @@
-;; No instrumentation should be emitted if there are no counter increments.
+;; Emit the runtime hook even if there are no counter increments.
 
-; RUN: opt < %s -instrprof -S | FileCheck %s
-; RUN: opt < %s -passes=instrprof -S | FileCheck %s
+; RUN: opt < %s -mtriple=x86_64-apple-macosx10.10.0 -instrprof -S | FileCheck %s
+; RUN: opt < %s -mtriple=x86_64-apple-macosx10.10.0 -passes=instrprof -S | FileCheck %s
 ; CHECK-NOT: @__profc
 ; CHECK-NOT: @__profd
-; CHECK-NOT: @__llvm_profile_runtime
+; CHECK: @__llvm_profile_runtime
 
 define void @foo() {
   ret void