[OpenCL] Add missing -cl-no-signed-zeros option into driver

Add OCL option -cl-no-signed-zeros to driver options.

Also added to opencl.cl testcases.

Patch by Aaron En Ye Shi.

Differential Revision: http://reviews.llvm.org/D22067

llvm-svn: 274923
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 89f8ce0..59cb4010 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -564,7 +564,8 @@
                        Args.hasArg(OPT_cl_unsafe_math_optimizations) ||
                        Args.hasArg(OPT_cl_finite_math_only) ||
                        Args.hasArg(OPT_cl_fast_relaxed_math));
-  Opts.NoSignedZeros = Args.hasArg(OPT_fno_signed_zeros);
+  Opts.NoSignedZeros = (Args.hasArg(OPT_fno_signed_zeros) ||
+                        Args.hasArg(OPT_cl_no_signed_zeros));
   Opts.ReciprocalMath = Args.hasArg(OPT_freciprocal_math);
   Opts.NoZeroInitializedInBSS = Args.hasArg(OPT_mno_zero_initialized_in_bss);
   Opts.BackendOptions = Args.getAllArgValues(OPT_backend_option);