[clang][Driver] Add new the -use-spirv-backend option to enable the SPIRV backend instead of the SPIRV translator for HIP.

Author: mgcarrasco

clang/include/clang/Options/Options.td

@@ -1427,6 +1427,16 @@ def fhip_emit_relocatable : Flag<["-"], "fhip-emit-relocatable">,
   HelpText<"Compile HIP source to relocatable">;
 def fno_hip_emit_relocatable : Flag<["-"], "fno-hip-emit-relocatable">,
   HelpText<"Do not override toolchain to compile HIP source to relocatable">;
+def use_spirv_backend
+    : Flag<["-"], "use-spirv-backend">,
+      Group<hip_Group>,
+      Flags<[HelpHidden]>,
+      HelpText<"Use the SPIRV backend for compilation ">;
+def no_use_spirv_backend
+    : Flag<["-"], "no-use-spirv-backend">,
+      Group<hip_Group>,
+      Flags<[HelpHidden]>,
+      HelpText<"Do not use the SPIRV backend for compilation ">;
 }
 
 // Clang specific/exclusive options for OpenACC.