[clang] [HLSL] Resource initialization by constructors (PR #135120)

[Ashley Coleman via cfe-commits]

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@@ -3179,6 +3207,67 @@ void SemaHLSL::ActOnVariableDeclarator(VarDecl *VD) {
   }
 }
 
+static bool initVarDeclWithCtor(Sema &S, VarDecl *VD,
+                                MutableArrayRef<Expr *> Args) {
+  InitializedEntity Entity = InitializedEntity::InitializeVariable(VD);
+  InitializationKind Kind = InitializationKind::CreateDirect(
+      VD->getLocation(), SourceLocation(), SourceLocation());
+
+  InitializationSequence InitSeq(S, Entity, Kind, Args);
+  ExprResult Init = InitSeq.Perform(S, Entity, Kind, Args);
+
+  if (!Init.get())
+    return false;
+
+  VD->setInit(S.MaybeCreateExprWithCleanups(Init.get()));
+  VD->setInitStyle(VarDecl::CallInit);
+  S.CheckCompleteVariableDeclaration(VD);
+  return true;
+}
+
+static bool initGlobalResourceDecl(Sema &S, VarDecl *VD) {
+  HLSLResourceBindingAttr *RBA = VD->getAttr<HLSLResourceBindingAttr>();
+  if (!RBA)
+    // FIXME: add support for implicit binding (llvm/llvm-project#110722)
+    return false;
+
+  ASTContext &AST = S.getASTContext();
+  uint64_t UIntTySize = AST.getTypeSize(AST.UnsignedIntTy);
+  uint64_t IntTySize = AST.getTypeSize(AST.IntTy);
+  Expr *Args[] = {
+      IntegerLiteral::Create(AST, llvm::APInt(UIntTySize, RBA->getSlotNumber()),
+                             AST.UnsignedIntTy, SourceLocation()),
+      IntegerLiteral::Create(AST,
+                             llvm::APInt(UIntTySize, RBA->getSpaceNumber()),
+                             AST.UnsignedIntTy, SourceLocation()),
+      IntegerLiteral::Create(AST, llvm::APInt(IntTySize, 1), AST.IntTy,
+                             SourceLocation()),
+      IntegerLiteral::Create(AST, llvm::APInt(UIntTySize, 0), AST.UnsignedIntTy,
+                             SourceLocation())};
+
+  return initVarDeclWithCtor(S, VD, Args);
+}
+
+// Returns true in the initialization has been handled;
+// Return false to let Clang handle the default initializaton.
----------------
V-FEXrt wrote:

nit: Aren't "we" clang? Does it make sense to just say

"Return false to use default initialization"?

https://github.com/llvm/llvm-project/pull/135120