Index: llvm/trunk/include/llvm/LTO/legacy/ThinLTOCodeGenerator.h
===================================================================
--- llvm/trunk/include/llvm/LTO/legacy/ThinLTOCodeGenerator.h
+++ llvm/trunk/include/llvm/LTO/legacy/ThinLTOCodeGenerator.h
@@ -287,6 +287,13 @@
    */
   void optimize(Module &Module);
 
+  /**
+   * Write temporary object file to SavedObjectDirectoryPath, write symlink
+   * to Cache directory if needed. Returns the path to the generated file in
+   * SavedObjectsDirectoryPath.
+   */
+  std::string writeGeneratedObject(int count, StringRef CacheEntryPath,
+                                   const MemoryBuffer &OutputBuffer);
   /**@}*/
 
 private:
Index: llvm/trunk/lib/LTO/ThinLTOCodeGenerator.cpp
===================================================================
--- llvm/trunk/lib/LTO/ThinLTOCodeGenerator.cpp
+++ llvm/trunk/lib/LTO/ThinLTOCodeGenerator.cpp
@@ -815,11 +815,13 @@
 /// Write out the generated object file, either from CacheEntryPath or from
 /// OutputBuffer, preferring hard-link when possible.
 /// Returns the path to the generated file in SavedObjectsDirectoryPath.
-static std::string writeGeneratedObject(int count, StringRef CacheEntryPath,
-                                        StringRef SavedObjectsDirectoryPath,
-                                        const MemoryBuffer &OutputBuffer) {
+std::string
+ThinLTOCodeGenerator::writeGeneratedObject(int count, StringRef CacheEntryPath,
+                                           const MemoryBuffer &OutputBuffer) {
+  auto ArchName = TMBuilder.TheTriple.getArchName();
   SmallString<128> OutputPath(SavedObjectsDirectoryPath);
-  llvm::sys::path::append(OutputPath, Twine(count) + ".thinlto.o");
+  llvm::sys::path::append(OutputPath,
+                          Twine(count) + "." + ArchName + ".thinlto.o");
   OutputPath.c_str(); // Ensure the string is null terminated.
   if (sys::fs::exists(OutputPath))
     sys::fs::remove(OutputPath);
@@ -882,8 +884,8 @@
         if (SavedObjectsDirectoryPath.empty())
           ProducedBinaries[count] = std::move(OutputBuffer);
         else
-          ProducedBinaryFiles[count] = writeGeneratedObject(
-              count, "", SavedObjectsDirectoryPath, *OutputBuffer);
+          ProducedBinaryFiles[count] =
+              writeGeneratedObject(count, "", *OutputBuffer);
       }, count++);
     }
 
@@ -1006,8 +1008,7 @@
               ProducedBinaries[count] = std::move(ErrOrBuffer.get());
             else
               ProducedBinaryFiles[count] = writeGeneratedObject(
-                  count, CacheEntryPath, SavedObjectsDirectoryPath,
-                  *ErrOrBuffer.get());
+                  count, CacheEntryPath, *ErrOrBuffer.get());
             return;
           }
         }
@@ -1064,7 +1065,7 @@
           return;
         }
         ProducedBinaryFiles[count] = writeGeneratedObject(
-            count, CacheEntryPath, SavedObjectsDirectoryPath, *OutputBuffer);
+            count, CacheEntryPath, *OutputBuffer);
       }, IndexCount);
     }
   }
Index: llvm/trunk/test/ThinLTO/X86/save_objects.ll
===================================================================
--- llvm/trunk/test/ThinLTO/X86/save_objects.ll
+++ llvm/trunk/test/ThinLTO/X86/save_objects.ll
@@ -20,6 +20,9 @@
 ; RUN: ls %t.thin.out | count 2
 ; RUN: ls %t.cache | count 3
 
+; Check the name of object in directory has arch name included.
+; RUN: ls %t.thin.out | grep x86_64.thinlto.o | count 2
+
 
 target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-apple-macosx10.11.0"