[llvm] [DXIL] Add support for root signature flag element in DXContainer (PR #123147)

[via llvm-commits]

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@@ -144,6 +150,30 @@ void DXContainerGlobals::addSignature(Module &M,
   Globals.emplace_back(buildSignature(M, OutputSig, "dx.osg1", "OSG1"));
 }
 
+void DXContainerGlobals::addRootSignature(Module &M,
+                                          SmallVector<GlobalValue *> &Globals) {
+
+  auto &RSA = getAnalysis<RootSignatureAnalysisWrapper>();
+  std::optional<ModuleRootSignature> MaybeRootSignature = RSA.getResult();
+
+  if (!MaybeRootSignature.has_value())
+    return;
+
+  ModuleRootSignature MRS = MaybeRootSignature.value();
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joaosaffran wrote:

Is there an optimization we can run that removes such copies? Asking because once we have everything in place, we will have RFA.getResult() all over the place to move the values around. So thinking if there is a better way to write it without having copies

https://github.com/llvm/llvm-project/pull/123147