Do not run dead code elimination by default

The dead code elimination is a pass that looks very promising, but needs some
more compile-time tuning before enabling it by default seems sensible.

llvm-svn: 223965

polly/lib/Support/RegisterPasses.cpp

@@ -99,7 +99,7 @@ static cl::opt<bool> ExportJScop(
 
 static cl::opt<bool> DeadCodeElim("polly-run-dce",
                                   cl::desc("Run the dead code elimination"),
-                                  cl::Hidden, cl::init(true), cl::ZeroOrMore,
+                                  cl::Hidden, cl::init(false), cl::ZeroOrMore,
                                   cl::cat(PollyCategory));
 
 static cl::opt<bool> PollyViewer(