[clang] [HLSL][RootSignature] Enable resource range analysis for remaining `RootElement`s (PR #145109)

[Finn Plummer via cfe-commits]

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@@ -1116,6 +1116,52 @@ bool SemaHLSL::handleRootSignatureDecl(HLSLRootSignatureDecl *D,
       Info.Space = Descriptor->Space;
       Info.Visibility = Descriptor->Visibility;
       Infos.push_back(Info);
+    } else if (const auto *Constants =
+                   std::get_if<llvm::hlsl::rootsig::RootConstants>(&Elem)) {
+      RangeInfo Info;
+      Info.LowerBound = Constants->Reg.Number;
+      Info.UpperBound = Info.LowerBound; // use inclusive ranges []
+
+      Info.Class = llvm::dxil::ResourceClass::CBuffer;
+      Info.Space = Constants->Space;
+      Info.Visibility = Constants->Visibility;
+      Infos.push_back(Info);
+    } else if (const auto *Sampler =
+                   std::get_if<llvm::hlsl::rootsig::StaticSampler>(&Elem)) {
+      RangeInfo Info;
+      Info.LowerBound = Sampler->Reg.Number;
+      Info.UpperBound = Info.LowerBound; // use inclusive ranges []
+
+      Info.Class = llvm::dxil::ResourceClass::Sampler;
+      Info.Space = Sampler->Space;
+      Info.Visibility = Sampler->Visibility;
+      Infos.push_back(Info);
+    } else if (const auto *Clause =
+                   std::get_if<llvm::hlsl::rootsig::DescriptorTableClause>(
+                       &Elem)) {
+      RangeInfo Info;
+      Info.LowerBound = Clause->Reg.Number;
+      assert(0 < Clause->NumDescriptors && "Verified as part of TODO(#129940)");
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inbelic wrote:

True, there shouldn't be anything to prevent us from doing so

https://github.com/llvm/llvm-project/pull/145109