[clang] [HLSL][DirectX] Add the Qdx-rootsignature-strip driver option (PR #154454)

[Farzon Lotfi via cfe-commits]

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@@ -295,6 +295,32 @@ void tools::hlsl::MetalConverter::ConstructJob(
                                          Exec, CmdArgs, Inputs, Input));
 }
 
+void tools::LLVMObjcopy::ConstructJob(Compilation &C, const JobAction &JA,
+                                      const InputInfo &Output,
+                                      const InputInfoList &Inputs,
+                                      const ArgList &Args,
+                                      const char *LinkingOutput) const {
+
+  std::string ObjcopyPath = getToolChain().GetProgramPath("llvm-objcopy");
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farzonl wrote:

don't work much in the driver, should we be using a std:string here, I've noticed this file uses StringRef in other places.

https://github.com/llvm/llvm-project/pull/154454