diff --git a/llvm/include/llvm/ProfileData/SampleProf.h b/llvm/include/llvm/ProfileData/SampleProf.h
--- a/llvm/include/llvm/ProfileData/SampleProf.h
+++ b/llvm/include/llvm/ProfileData/SampleProf.h
@@ -728,7 +728,7 @@
 using BodySampleMap = std::map<LineLocation, SampleRecord>;
 // NOTE: Using a StringMap here makes parsed profiles consume around 17% more
 // memory, which is *very* significant for large profiles.
-using FunctionSamplesMap = std::map<std::string, FunctionSamples, std::less<>>;
+using FunctionSamplesMap = std::map<StringRef, FunctionSamples>;
 using CallsiteSampleMap = std::map<LineLocation, FunctionSamplesMap>;
 using LocToLocMap =
     std::unordered_map<LineLocation, LineLocation, LineLocationHash>;
diff --git a/llvm/lib/ProfileData/SampleProf.cpp b/llvm/lib/ProfileData/SampleProf.cpp
--- a/llvm/lib/ProfileData/SampleProf.cpp
+++ b/llvm/lib/ProfileData/SampleProf.cpp
@@ -474,7 +474,7 @@
     if (NodeProfile) {
       // Add child profile to the callsite profile map.
       auto &SamplesMap = NodeProfile->functionSamplesAt(ChildNode.CallSiteLoc);
-      SamplesMap.emplace(OrigChildContext.getName().str(), *ChildProfile);
+      SamplesMap.emplace(OrigChildContext.getName(), *ChildProfile);
       NodeProfile->addTotalSamples(ChildProfile->getTotalSamples());
       // Remove the corresponding body sample for the callsite and update the
       // total weight.
@@ -498,7 +498,7 @@
       ProfileMap[ChildProfile->getContext()].merge(*ChildProfile);
       NewChildProfileHash = ChildProfile->getContext().getHashCode();
       auto &SamplesMap = NodeProfile->functionSamplesAt(ChildNode.CallSiteLoc);
-      SamplesMap[ChildProfile->getName().str()].getContext().setAttribute(
+      SamplesMap[ChildProfile->getName()].getContext().setAttribute(
           ContextDuplicatedIntoBase);
     }
 
diff --git a/llvm/lib/ProfileData/SampleProfReader.cpp b/llvm/lib/ProfileData/SampleProfReader.cpp
--- a/llvm/lib/ProfileData/SampleProfReader.cpp
+++ b/llvm/lib/ProfileData/SampleProfReader.cpp
@@ -392,7 +392,7 @@
       switch (LineTy) {
       case LineType::CallSiteProfile: {
         FunctionSamples &FSamples = InlineStack.back()->functionSamplesAt(
-            LineLocation(LineOffset, Discriminator))[std::string(FName)];
+            LineLocation(LineOffset, Discriminator))[FName];
         FSamples.setName(FName);
         MergeResult(Result, FSamples.addTotalSamples(NumSamples));
         InlineStack.push_back(&FSamples);
@@ -657,7 +657,7 @@
     uint32_t DiscriminatorVal = (*Discriminator) & getDiscriminatorMask();
 
     FunctionSamples &CalleeProfile = FProfile.functionSamplesAt(
-        LineLocation(*LineOffset, DiscriminatorVal))[std::string(*FName)];
+        LineLocation(*LineOffset, DiscriminatorVal))[*FName];
     CalleeProfile.setName(*FName);
     if (std::error_code EC = readProfile(CalleeProfile))
       return EC;
@@ -1252,7 +1252,7 @@
           CalleeProfile = const_cast<FunctionSamples *>(
               &FProfile->functionSamplesAt(LineLocation(
                   *LineOffset,
-                  *Discriminator))[std::string(FContext.getName())]);
+                  *Discriminator))[FContext.getName()]);
         }
         if (std::error_code EC =
                 readFuncMetadata(ProfileHasAttribute, CalleeProfile))
@@ -1674,7 +1674,7 @@
     uint32_t LineOffset = Offset >> 16;
     uint32_t Discriminator = Offset & 0xffff;
     FProfile = &CallerProfile->functionSamplesAt(
-        LineLocation(LineOffset, Discriminator))[std::string(Name)];
+        LineLocation(LineOffset, Discriminator))[Name];
   }
   FProfile->setName(Name);
 
diff --git a/llvm/tools/llvm-profdata/llvm-profdata.cpp b/llvm/tools/llvm-profdata/llvm-profdata.cpp
--- a/llvm/tools/llvm-profdata/llvm-profdata.cpp
+++ b/llvm/tools/llvm-profdata/llvm-profdata.cpp
@@ -904,8 +904,7 @@
     for (const auto &Callsite : CallsiteSamples.second) {
       sampleprof::FunctionSamples Remapped =
           remapSamples(Callsite.second, Remapper, Error);
-      MergeResult(Error,
-                  Target[std::string(Remapped.getName())].merge(Remapped));
+      MergeResult(Error, Target[Remapped.getName()].merge(Remapped));
     }
   }
   return Result;
diff --git a/llvm/tools/llvm-profgen/ProfileGenerator.cpp b/llvm/tools/llvm-profgen/ProfileGenerator.cpp
--- a/llvm/tools/llvm-profgen/ProfileGenerator.cpp
+++ b/llvm/tools/llvm-profgen/ProfileGenerator.cpp
@@ -610,7 +610,7 @@
     FunctionSamplesMap &SamplesMap =
         FunctionProfile->functionSamplesAt(Callsite);
     auto Ret =
-        SamplesMap.emplace(FrameVec[I].FuncName.str(), FunctionSamples());
+        SamplesMap.emplace(FrameVec[I].FuncName, FunctionSamples());
     if (Ret.second) {
       SampleContext Context(FrameVec[I].FuncName);
       Ret.first->second.setContext(Context);
diff --git a/llvm/unittests/ProfileData/SampleProfTest.cpp b/llvm/unittests/ProfileData/SampleProfTest.cpp
--- a/llvm/unittests/ProfileData/SampleProfTest.cpp
+++ b/llvm/unittests/ProfileData/SampleProfTest.cpp
@@ -157,7 +157,7 @@
     // Add inline instance with name "_Z3gooi".
     StringRef GooName("_Z3gooi");
     auto &GooSamples =
-        FooSamples.functionSamplesAt(LineLocation(7, 0))[GooName.str()];
+        FooSamples.functionSamplesAt(LineLocation(7, 0))[GooName];
     GooSamples.setName(GooName);
     GooSamples.addTotalSamples(502);
     GooSamples.addBodySamples(3, 0, 502);
@@ -165,7 +165,7 @@
     // Add inline instance with name "_Z3hooi".
     StringRef HooName("_Z3hooi");
     auto &HooSamples =
-        GooSamples.functionSamplesAt(LineLocation(9, 0))[HooName.str()];
+        GooSamples.functionSamplesAt(LineLocation(9, 0))[HooName];
     HooSamples.setName(HooName);
     HooSamples.addTotalSamples(317);
     HooSamples.addBodySamples(4, 0, 317);