[clang] Teach opaque offload driver to pass args to opt

Change-Id: I1e3e67b36a3ebc3ffb84a80732cf33c0bd096348

Author: macurtis-amd

clang/include/clang/Driver/Options.td

@@ -1056,6 +1056,9 @@ def Xlinker : Separate<["-"], "Xlinker">, Flags<[LinkerInput, RenderAsInput]>,
 def Xoffload_linker : JoinedAndSeparate<["-"], "Xoffload-linker">,
   HelpText<"Pass <arg> to the offload linkers or the ones idenfied by -<triple>">,
   MetaVarName<"<triple> <arg>">, Group<Link_Group>;
+def Xopaque_offload_opt : Separate<["-"], "Xopaque-offload-opt">,
+  HelpText<"Pass <arg> to the opaque offload optimizer">,
+  MetaVarName<"<arg>">, Visibility<[ClangOption, FlangOption]>;
 def Xpreprocessor : Separate<["-"], "Xpreprocessor">, Group<Preprocessor_Group>,
   HelpText<"Pass <arg> to the preprocessor">, MetaVarName<"<arg>">;
 def X_Flag : Flag<["-"], "X">, Group<Link_Group>;

clang/lib/Driver/ToolChains/Clang.cpp

@@ -9437,6 +9437,13 @@ void LinkerWrapper::ConstructOpaqueJob(Compilation &C, const JobAction &JA,
 
     // ---------- Step 4 opt  -----------
     ArgStringList OptArgs;
+
+    // Forward -Xopaque-offload-opt arguments to the 'opt' job.
+    for (Arg *A : Args.filtered(options::OPT_Xopaque_offload_opt)) {
+      OptArgs.push_back(A->getValue());
+      A->claim();
+    }
+
     auto OptOutputFileName = amdgpu::dlr::getOptCommandArgs(
         C, Args, OptArgs, TheTriple, TargetID, OutputFilePrefix,
         LinkOutputFileName);