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

[Justin Bogner via llvm-commits]

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@@ -144,6 +150,39 @@ void DXContainerGlobals::addSignature(Module &M,
   Globals.emplace_back(buildSignature(M, OutputSig, "dx.osg1", "OSG1"));
 }
 
+void DXContainerGlobals::addRootSignature(Module &M,
+                                          SmallVector<GlobalValue *> &Globals) {
+
+  dxil::ModuleMetadataInfo &MMI =
+      getAnalysis<DXILMetadataAnalysisWrapperPass>().getModuleMetadata();
+
+  // Root Signature in Library shaders are different,
+  // since they don't use DXContainer to share it.
+  if (MMI.ShaderProfile == llvm::Triple::Library)
+    return;
+
+  assert(MMI.EntryPropertyVec.size() == 1);
+
+  auto &RSA = getAnalysis<RootSignatureAnalysisWrapper>();
+  const Function *&EntryFunction = MMI.EntryPropertyVec[0].Entry;
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bogner wrote:

A const ref to a pointer is pretty strange. Is this what we really want here? I suspect just copying the pointer is fine.

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