[clang] [HLSL] Collect explicit resource binding information (PR #111203)

[Justin Bogner via cfe-commits]

================
@@ -2235,3 +2280,107 @@ QualType SemaHLSL::getInoutParameterType(QualType Ty) {
   Ty.addRestrict();
   return Ty;
 }
+
+void SemaHLSL::ActOnVariableDeclarator(VarDecl *VD) {
+  if (VD->hasGlobalStorage()) {
+    // make sure the declaration has a complete type
+    if (SemaRef.RequireCompleteType(
+            VD->getLocation(),
+            SemaRef.getASTContext().getBaseElementType(VD->getType()),
+            diag::err_typecheck_decl_incomplete_type)) {
+      VD->setInvalidDecl();
+      return;
+    }
+
+    // find all resources on decl
+    if (IsIntangibleType(VD->getType()))
+      FindResourcesOnVarDecl(VD);
+
+    // process explicit bindings
+    ProcessExplicitBindingsOnDecl(VD);
+  }
+}
+
+// Walks though the global variable declaration, collects all resource binding
+// requirements and adds them to Bindings
+void SemaHLSL::FindResourcesOnVarDecl(VarDecl *VD) {
+  assert(VD->hasGlobalStorage() && IsIntangibleType(VD->getType()) &&
+         "expected global variable that contains HLSL resource");
+
+  // Cbuffers and Tbuffers are HLSLBufferDecl types
+  if (const HLSLBufferDecl *CBufferOrTBuffer = dyn_cast<HLSLBufferDecl>(VD)) {
+    Bindings.addDeclBindingInfo(VD,
+                                CBufferOrTBuffer->isCBuffer()
+                                    ? ResourceClass::CBuffer
+                                    : ResourceClass::SRV,
+                                1);
+    return;
+  }
+
+  // Calculate size of array and unwrap
+  int Size = 1;
+  const Type *Ty = VD->getType()->getUnqualifiedDesugaredType();
+  if (Ty->isIncompleteArrayType())
+    Size = -1;
+  while (Ty->isConstantArrayType()) {
+    const ConstantArrayType *CAT = cast<ConstantArrayType>(Ty);
+    Size *= CAT->getSize().getSExtValue();
+    Ty = CAT->getElementType()->getUnqualifiedDesugaredType();
+  }
----------------
bogner wrote:

Is it possible to have an incomplete array type on one of the nested arrays here?

https://github.com/llvm/llvm-project/pull/111203