Fix bugpoint execution/reference output file name

sys::fs::unique_file will now loop infinitely if provided with a file name
without '%' characters and the input file already exists. As a result, bugpoint
cannot use a fixed file name for the execution output (including the reference
output).

llvm-svn: 185166

llvm/tools/bugpoint/BugDriver.h

@@ -191,7 +191,7 @@ public:
   /// this function.
   ///
   bool createReferenceFile(Module *M, const std::string &Filename
-                                            = "bugpoint.reference.out");
+                                            = "bugpoint.reference.out-%%%%%%%");
 
   /// diffProgram - This method executes the specified module and diffs the
   /// output against the file specified by ReferenceOutputFile.  If the output

llvm/tools/bugpoint/ExecutionDriver.cpp

@@ -328,7 +328,7 @@ std::string BugDriver::executeProgram(const Module *Program,
   FileRemover BitcodeFileRemover(BitcodePath,
     CreatedBitcode && !SaveTemps);
 
-  if (OutputFile.empty()) OutputFile = OutputPrefix + "-execution-output";
+  if (OutputFile.empty()) OutputFile = OutputPrefix + "-execution-output-%%%%%%%";
 
   // Check to see if this is a valid output filename...
   SmallString<128> UniqueFile;