Generalize my previous fix for -print-options.

Always print options that differ from their implicit default. At least
for simple option types.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176572 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Support/CommandLine.h

@@ -1090,7 +1090,7 @@ public:
 
   // Make sure we initialize the value with the default constructor for the
   // type.
-  opt_storage() : Value(DataType()) {}
+  opt_storage() : Value(DataType()), Default(DataType()) {}
 
   template<class T>
   void setValue(const T &V, bool initial = false) {

lib/Transforms/IPO/PassManagerBuilder.cpp

@@ -29,7 +29,7 @@
 using namespace llvm;
 
 static cl::opt<bool>
-RunLoopVectorization("vectorize-loops", cl::init(false),
+RunLoopVectorization("vectorize-loops",
                      cl::desc("Run the Loop vectorization passes"));
 
 static cl::opt<bool>