Index: lib/CodeGen/TargetLoweringObjectFileImpl.cpp
===================================================================
--- lib/CodeGen/TargetLoweringObjectFileImpl.cpp
+++ lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -294,6 +294,13 @@
     Name = getSectionPrefixForGlobal(Kind);
   }
 
+  // TODO: update when API is available to check if a function is hot.
+  if (const Function *F = dyn_cast<Function>(GV)) {
+    if (F->getEntryCount()) {
+      Name += ".hot";
+    }
+  }
+
   if (EmitUniqueSection && UniqueSectionNames) {
     Name.push_back('.');
     TM.getNameWithPrefix(Name, GV, Mang, true);