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

[Finn Plummer via cfe-commits]

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@@ -42,7 +42,21 @@ class LLVM_LIBRARY_VISIBILITY MetalConverter : public Tool {
                     const llvm::opt::ArgList &TCArgs,
                     const char *LinkingOutput) const override;
 };
+
 } // namespace hlsl
+
+class LLVM_LIBRARY_VISIBILITY LLVMObjcopy : public Tool {
+public:
+  LLVMObjcopy(const ToolChain &TC) : Tool("LLVMObjcopy", "llvm-objcopy", TC) {}
+
+  bool hasIntegratedCPP() const override { return false; }
+
+  void ConstructJob(Compilation &C, const JobAction &JA,
+                    const InputInfo &Output, const InputInfoList &Inputs,
+                    const llvm::opt::ArgList &TCArgs,
+                    const char *LinkingOutput) const override;
+};
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inbelic wrote:

While it is generic, the logic of `ConstructJob` is specific to just the `hlsl` toolchain.

It is convention for the other toolchains to each redefine their own version of the struct with their namespace prefixed.  See `Linker` etc.

So I have added back the `hlsl` namespace to this struct.

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