[HLSL] Collect explicit resource binding information

clang/include/clang/Basic/Attr.td

@@ -4588,6 +4588,35 @@ def HLSLResourceBinding: InheritableAttr {
   let LangOpts = [HLSL];
   let Args = [StringArgument<"Slot">, StringArgument<"Space", 1>];
   let Documentation = [HLSLResourceBindingDocs];
+  let AdditionalMembers = [{
+      enum class RegisterType : unsigned { SRV, UAV, CBuffer, Sampler, C, I, Invalid };
+
+      const FieldDecl *ResourceField = nullptr;
+      RegisterType RegType;
+      unsigned SlotNumber;
+      unsigned SpaceNumber;
+
+      void setBinding(RegisterType RT, unsigned SlotNum, unsigned SpaceNum) {
+        RegType = RT;
+        SlotNumber = SlotNum;
+        SpaceNumber = SpaceNum;
+      }
+      void setResourceField(const FieldDecl *FD) {
+        ResourceField = FD;
+      }
+      const FieldDecl *getResourceField() {
+        return ResourceField;
+      }
+      RegisterType getRegisterType() {
+        return RegType;
+      }
+      unsigned getSlotNumber() {
+        return SlotNumber;
+      }
+      unsigned getSpaceNumber() {
+        return SpaceNumber;
+      }
+  }];
 }
 
 def HLSLPackOffset: HLSLAnnotationAttr {

clang/include/clang/Sema/SemaHLSL.h

@@ -28,6 +28,7 @@ class AttributeCommonInfo;
 class IdentifierInfo;
 class ParsedAttr;
 class Scope;
+class VarDecl;
 
 // FIXME: This can be hidden (as static function in SemaHLSL.cpp) once we no
 // longer need to create builtin buffer types in HLSLExternalSemaSource.
@@ -62,6 +63,7 @@ class SemaHLSL : public SemaBase {
       const Attr *A, llvm::Triple::EnvironmentType Stage,
       std::initializer_list<llvm::Triple::EnvironmentType> AllowedStages);
   void DiagnoseAvailabilityViolations(TranslationUnitDecl *TU);
+  void ProcessResourceBindingOnDecl(VarDecl *D);
 
   QualType handleVectorBinOpConversion(ExprResult &LHS, ExprResult &RHS,
                                        QualType LHSType, QualType RHSType,

clang/lib/Sema/SemaDecl.cpp

@@ -7876,6 +7876,9 @@ NamedDecl *Sema::ActOnVariableDeclarator(
   // Handle attributes prior to checking for duplicates in MergeVarDecl
   ProcessDeclAttributes(S, NewVD, D);
 
+  if (getLangOpts().HLSL)
+    HLSL().ProcessResourceBindingOnDecl(NewVD);
+
   // FIXME: This is probably the wrong location to be doing this and we should
   // probably be doing this for more attributes (especially for function
   // pointer attributes such as format, warn_unused_result, etc.). Ideally