CUDA: add -fcuda-is-device flag

This frontend-only flag is used by the IR generator to determine
whether to filter CUDA declarations for the host or for the device.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@141301 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Driver/CC1Options.td b/include/clang/Driver/CC1Options.td
index ffe1eaf..ef83cbc 100644
--- a/include/clang/Driver/CC1Options.td
+++ b/include/clang/Driver/CC1Options.td
@@ -714,3 +714,10 @@
   HelpText<"OpenCL only. Enable less precise MAD instructions to be generated.">;
 def cl_std_EQ : Joined<"-cl-std=">,
   HelpText<"OpenCL language standard to compile for">;
+
+//===----------------------------------------------------------------------===//
+// CUDA Options
+//===----------------------------------------------------------------------===//
+
+def fcuda_is_device : Flag<"-fcuda-is-device">,
+  HelpText<"Generate code for CUDA device">;