Revert "[HLSL][RootSignature] Define and integrate rootsig clang attr and decl"

inbelic · inbelic · commit 2d72752cb9f8 · 2025-05-12T17:35:10.000Z
Reverts llvm#137690 - there is a build warning (treated as erorr) that `SignatureDecl` is unused, which is correct as it was not removed from prototyping
diff --git a/clang/include/clang/AST/Decl.h b/clang/include/clang/AST/Decl.h
@@ -41,7 +41,6 @@
 #include "llvm/ADT/PointerUnion.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/ADT/iterator_range.h"
-#include "llvm/Frontend/HLSL/HLSLRootSignature.h"
 #include "llvm/Support/Casting.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/TrailingObjects.h"
@@ -5179,42 +5178,6 @@ class HLSLBufferDecl final : public NamedDecl, public DeclContext {
   friend class ASTDeclWriter;
 };
 
-class HLSLRootSignatureDecl final
-    : public NamedDecl,
-      private llvm::TrailingObjects<HLSLRootSignatureDecl,
-                                    llvm::hlsl::rootsig::RootElement> {
-  friend TrailingObjects;
-
-  unsigned NumElems;
-
-  llvm::hlsl::rootsig::RootElement *getElems() {
-    return getTrailingObjects<llvm::hlsl::rootsig::RootElement>();
-  }
-
-  const llvm::hlsl::rootsig::RootElement *getElems() const {
-    return getTrailingObjects<llvm::hlsl::rootsig::RootElement>();
-  }
-
-  HLSLRootSignatureDecl(DeclContext *DC, SourceLocation Loc, IdentifierInfo *ID,
-                        unsigned NumElems);
-
-public:
-  static HLSLRootSignatureDecl *
-  Create(ASTContext &C, DeclContext *DC, SourceLocation Loc, IdentifierInfo *ID,
-         ArrayRef<llvm::hlsl::rootsig::RootElement> RootElements);
-
-  static HLSLRootSignatureDecl *CreateDeserialized(ASTContext &C,
-                                                   GlobalDeclID ID);
-
-  ArrayRef<llvm::hlsl::rootsig::RootElement> getRootElements() const {
-    return {getElems(), NumElems};
-  }
-
-  // Implement isa/cast/dyncast/etc.
-  static bool classof(const Decl *D) { return classofKind(D->getKind()); }
-  static bool classofKind(Kind K) { return K == HLSLRootSignature; }
-};
-
 /// Insertion operator for diagnostics.  This allows sending NamedDecl's
 /// into a diagnostic with <<.
 inline const StreamingDiagnostic &operator<<(const StreamingDiagnostic &PD,
diff --git a/clang/include/clang/AST/RecursiveASTVisitor.h b/clang/include/clang/AST/RecursiveASTVisitor.h
@@ -1599,8 +1599,6 @@ DEF_TRAVERSE_DECL(EmptyDecl, {})
 
 DEF_TRAVERSE_DECL(HLSLBufferDecl, {})
 
-DEF_TRAVERSE_DECL(HLSLRootSignatureDecl, {})
-
 DEF_TRAVERSE_DECL(LifetimeExtendedTemporaryDecl, {
   TRY_TO(TraverseStmt(D->getTemporaryExpr()));
 })
diff --git a/clang/include/clang/AST/TextNodeDumper.h b/clang/include/clang/AST/TextNodeDumper.h
@@ -408,7 +408,6 @@ class TextNodeDumper
   void
   VisitLifetimeExtendedTemporaryDecl(const LifetimeExtendedTemporaryDecl *D);
   void VisitHLSLBufferDecl(const HLSLBufferDecl *D);
-  void VisitHLSLRootSignatureDecl(const HLSLRootSignatureDecl *D);
   void VisitHLSLOutArgExpr(const HLSLOutArgExpr *E);
   void VisitOpenACCConstructStmt(const OpenACCConstructStmt *S);
   void VisitOpenACCLoopConstruct(const OpenACCLoopConstruct *S);
diff --git a/clang/include/clang/Basic/Attr.td b/clang/include/clang/Basic/Attr.td
@@ -4735,17 +4735,6 @@ def Error : InheritableAttr {
   let Documentation = [ErrorAttrDocs];
 }
 
-/// HLSL Root Signature Attribute
-def RootSignature : Attr {
-  /// [RootSignature(Signature)]
-  let Spellings = [Microsoft<"RootSignature">];
-  let Args = [IdentifierArgument<"Signature">];
-  let Subjects = SubjectList<[Function],
-                             ErrorDiag, "'function'">;
-  let LangOpts = [HLSL];
-  let Documentation = [RootSignatureDocs];
-}
-
 def HLSLNumThreads: InheritableAttr {
   let Spellings = [Microsoft<"numthreads">];
   let Args = [IntArgument<"X">, IntArgument<"Y">, IntArgument<"Z">];
diff --git a/clang/include/clang/Basic/AttrDocs.td b/clang/include/clang/Basic/AttrDocs.td
@@ -8195,17 +8195,6 @@ and https://microsoft.github.io/hlsl-specs/proposals/0013-wave-size-range.html
   }];
 }
 
-def RootSignatureDocs : Documentation {
-  let Category = DocCatFunction;
-  let Content = [{
-The ``RootSignature`` attribute applies to HLSL entry functions to define what
-types of resources are bound to the graphics pipeline.
-
-For details about the use and specification of Root Signatures please see here:
-https://learn.microsoft.com/en-us/windows/win32/direct3d12/root-signatures
-  }];
-}
-
 def NumThreadsDocs : Documentation {
   let Category = DocCatFunction;
   let Content = [{
diff --git a/clang/include/clang/Basic/DeclNodes.td b/clang/include/clang/Basic/DeclNodes.td
@@ -111,6 +111,5 @@ def Empty : DeclNode<Decl>;
 def RequiresExprBody : DeclNode<Decl>, DeclContext;
 def LifetimeExtendedTemporary : DeclNode<Decl>;
 def HLSLBuffer : DeclNode<Named, "HLSLBuffer">, DeclContext;
-def HLSLRootSignature : DeclNode<Named, "HLSLRootSignature">;
 def OpenACCDeclare : DeclNode<Decl, "#pragma acc declare">;
 def OpenACCRoutine : DeclNode<Decl, "#pragma acc routine">;
diff --git a/clang/include/clang/Parse/Parser.h b/clang/include/clang/Parse/Parser.h
@@ -3093,7 +3093,6 @@ class Parser : public CodeCompletionHandler {
     return AttrsParsed;
   }
   void ParseMicrosoftUuidAttributeArgs(ParsedAttributes &Attrs);
-  void ParseMicrosoftRootSignatureAttributeArgs(ParsedAttributes &Attrs);
   void ParseMicrosoftAttributes(ParsedAttributes &Attrs);
   bool MaybeParseMicrosoftDeclSpecs(ParsedAttributes &Attrs) {
     if (getLangOpts().DeclSpecKeyword && Tok.is(tok::kw___declspec)) {
diff --git a/clang/include/clang/Sema/SemaHLSL.h b/clang/include/clang/Sema/SemaHLSL.h
@@ -119,7 +119,6 @@ class SemaHLSL : public SemaBase {
                                        bool IsCompAssign);
   void emitLogicalOperatorFixIt(Expr *LHS, Expr *RHS, BinaryOperatorKind Opc);
 
-  void handleRootSignatureAttr(Decl *D, const ParsedAttr &AL);
   void handleNumThreadsAttr(Decl *D, const ParsedAttr &AL);
   void handleWaveSizeAttr(Decl *D, const ParsedAttr &AL);
   void handleSV_DispatchThreadIDAttr(Decl *D, const ParsedAttr &AL);
diff --git a/clang/lib/AST/CMakeLists.txt b/clang/lib/AST/CMakeLists.txt
@@ -2,7 +2,6 @@ set(LLVM_LINK_COMPONENTS
   BinaryFormat
   Core
   FrontendOpenMP
-  FrontendHLSL
   Support
   TargetParser
   )
diff --git a/clang/lib/AST/Decl.cpp b/clang/lib/AST/Decl.cpp
@@ -5847,38 +5847,6 @@ bool HLSLBufferDecl::buffer_decls_empty() {
   return DefaultBufferDecls.empty() && decls_empty();
 }
 
-//===----------------------------------------------------------------------===//
-// HLSLRootSignatureDecl Implementation
-//===----------------------------------------------------------------------===//
-
-HLSLRootSignatureDecl::HLSLRootSignatureDecl(DeclContext *DC,
-                                             SourceLocation Loc,
-                                             IdentifierInfo *ID,
-                                             unsigned NumElems)
-    : NamedDecl(Decl::Kind::HLSLRootSignature, DC, Loc, DeclarationName(ID)),
-      NumElems(NumElems) {}
-
-HLSLRootSignatureDecl *HLSLRootSignatureDecl::Create(
-    ASTContext &C, DeclContext *DC, SourceLocation Loc, IdentifierInfo *ID,
-    ArrayRef<llvm::hlsl::rootsig::RootElement> RootElements) {
-  HLSLRootSignatureDecl *RSDecl =
-      new (C, DC,
-           additionalSizeToAlloc<llvm::hlsl::rootsig::RootElement>(
-               RootElements.size()))
-          HLSLRootSignatureDecl(DC, Loc, ID, RootElements.size());
-  auto *StoredElems = RSDecl->getElems();
-  std::uninitialized_copy(RootElements.begin(), RootElements.end(),
-                          StoredElems);
-  return RSDecl;
-}
-
-HLSLRootSignatureDecl *
-HLSLRootSignatureDecl::CreateDeserialized(ASTContext &C, GlobalDeclID ID) {
-  HLSLRootSignatureDecl *Result = new (C, ID)
-      HLSLRootSignatureDecl(nullptr, SourceLocation(), nullptr, /*NumElems=*/0);
-  return Result;
-}
-
 //===----------------------------------------------------------------------===//
 // ImportDecl Implementation
 //===----------------------------------------------------------------------===//
diff --git a/clang/lib/AST/DeclBase.cpp b/clang/lib/AST/DeclBase.cpp
@@ -886,7 +886,6 @@ unsigned Decl::getIdentifierNamespaceForKind(Kind DeclKind) {
     case ObjCProperty:
     case MSProperty:
     case HLSLBuffer:
-    case HLSLRootSignature:
       return IDNS_Ordinary;
     case Label:
       return IDNS_Label;
diff --git a/clang/lib/AST/TextNodeDumper.cpp b/clang/lib/AST/TextNodeDumper.cpp
@@ -24,7 +24,6 @@
 #include "clang/Basic/Specifiers.h"
 #include "clang/Basic/TypeTraits.h"
 #include "llvm/ADT/StringExtras.h"
-#include "llvm/Frontend/HLSL/HLSLRootSignature.h"
 
 #include <algorithm>
 #include <utility>
@@ -3038,12 +3037,6 @@ void TextNodeDumper::VisitHLSLBufferDecl(const HLSLBufferDecl *D) {
   dumpName(D);
 }
 
-void TextNodeDumper::VisitHLSLRootSignatureDecl(
-    const HLSLRootSignatureDecl *D) {
-  dumpName(D);
-  llvm::hlsl::rootsig::dumpRootElements(OS, D->getRootElements());
-}
-
 void TextNodeDumper::VisitHLSLOutArgExpr(const HLSLOutArgExpr *E) {
   OS << (E->isInOut() ? " inout" : " out");
 }
diff --git a/clang/lib/CodeGen/CGDecl.cpp b/clang/lib/CodeGen/CGDecl.cpp
@@ -106,7 +106,6 @@ void CodeGenFunction::EmitDecl(const Decl &D, bool EvaluateConditionDecl) {
   case Decl::Binding:
   case Decl::UnresolvedUsingIfExists:
   case Decl::HLSLBuffer:
-  case Decl::HLSLRootSignature:
     llvm_unreachable("Declaration should not be in declstmts!");
   case Decl::Record:    // struct/union/class X;
   case Decl::CXXRecord: // struct/union/class X; [C++]
diff --git a/clang/lib/Parse/ParseDeclCXX.cpp b/clang/lib/Parse/ParseDeclCXX.cpp
@@ -21,12 +21,10 @@
 #include "clang/Basic/TargetInfo.h"
 #include "clang/Basic/TokenKinds.h"
 #include "clang/Lex/LiteralSupport.h"
-#include "clang/Parse/ParseHLSLRootSignature.h"
 #include "clang/Parse/Parser.h"
 #include "clang/Parse/RAIIObjectsForParser.h"
 #include "clang/Sema/DeclSpec.h"
 #include "clang/Sema/EnterExpressionEvaluationContext.h"
-#include "clang/Sema/Lookup.h"
 #include "clang/Sema/ParsedTemplate.h"
 #include "clang/Sema/Scope.h"
 #include "clang/Sema/SemaCodeCompletion.h"
@@ -5313,90 +5311,6 @@ void Parser::ParseMicrosoftUuidAttributeArgs(ParsedAttributes &Attrs) {
   }
 }
 
-void Parser::ParseMicrosoftRootSignatureAttributeArgs(ParsedAttributes &Attrs) {
-  assert(Tok.is(tok::identifier) &&
-         "Expected an identifier to denote which MS attribute to consider");
-  IdentifierInfo *RootSignatureIdent = Tok.getIdentifierInfo();
-  assert(RootSignatureIdent->getName() == "RootSignature" &&
-         "Expected RootSignature identifier for root signature attribute");
-
-  SourceLocation RootSignatureLoc = Tok.getLocation();
-  ConsumeToken();
-
-  // Ignore the left paren location for now.
-  BalancedDelimiterTracker T(*this, tok::l_paren);
-  if (T.consumeOpen()) {
-    Diag(Tok, diag::err_expected) << tok::l_paren;
-    return;
-  }
-
-  auto ProcessStringLiteral = [this]() -> std::optional<StringLiteral *> {
-    if (!isTokenStringLiteral())
-      return std::nullopt;
-
-    ExprResult StringResult = ParseUnevaluatedStringLiteralExpression();
-    if (StringResult.isInvalid())
-      return std::nullopt;
-
-    if (auto Lit = dyn_cast<StringLiteral>(StringResult.get()))
-      return Lit;
-
-    return std::nullopt;
-  };
-
-  auto StrLiteral = ProcessStringLiteral();
-  if (!StrLiteral.has_value()) {
-    Diag(Tok, diag::err_expected_string_literal)
-        << /*in attributes...*/ 4 << RootSignatureIdent->getName();
-    SkipUntil(tok::r_paren, StopAtSemi | StopBeforeMatch);
-    T.consumeClose();
-    return;
-  }
-
-  // Construct our identifier
-  StringRef Signature = StrLiteral.value()->getString();
-  auto Hash = llvm::hash_value(Signature);
-  std::string IdStr = "__hlsl_rootsig_decl_" + std::to_string(Hash);
-  IdentifierInfo *DeclIdent = &(Actions.getASTContext().Idents.get(IdStr));
-
-  LookupResult R(Actions, DeclIdent, SourceLocation(),
-                 Sema::LookupOrdinaryName);
-  // Check if we have already found a decl of the same name, if we haven't
-  // then parse the root signature string and construct the in-memory elements
-  if (!Actions.LookupQualifiedName(R, Actions.CurContext)) {
-    SourceLocation SignatureLoc =
-        StrLiteral.value()->getExprLoc().getLocWithOffset(
-            1); // offset 1 for '"'
-    // Invoke the root signature parser to construct the in-memory constructs
-    hlsl::RootSignatureLexer Lexer(Signature, SignatureLoc);
-    SmallVector<llvm::hlsl::rootsig::RootElement> RootElements;
-    hlsl::RootSignatureParser Parser(RootElements, Lexer, PP);
-    if (Parser.parse()) {
-      T.consumeClose();
-      return;
-    }
-
-    // Create the Root Signature
-    auto *SignatureDecl = HLSLRootSignatureDecl::Create(
-        Actions.getASTContext(), /*DeclContext=*/Actions.CurContext,
-        RootSignatureLoc, DeclIdent, RootElements);
-    SignatureDecl->setImplicit();
-    Actions.PushOnScopeChains(SignatureDecl, getCurScope());
-  }
-
-  // Create the arg for the ParsedAttr
-  IdentifierLoc *ILoc = ::new (Actions.getASTContext())
-      IdentifierLoc(RootSignatureLoc, DeclIdent);
-
-  ArgsVector Args = {ILoc};
-
-  if (!T.consumeClose())
-    Attrs.addNew(RootSignatureIdent,
-                 SourceRange(RootSignatureLoc, T.getCloseLocation()), nullptr,
-                 SourceLocation(), Args.data(), Args.size(),
-                 ParsedAttr::Form::Microsoft());
-}
-
 /// ParseMicrosoftAttributes - Parse Microsoft attributes [Attr]
 ///
 /// [MS] ms-attribute:
@@ -5431,8 +5345,6 @@ void Parser::ParseMicrosoftAttributes(ParsedAttributes &Attrs) {
         break;
       if (Tok.getIdentifierInfo()->getName() == "uuid")
         ParseMicrosoftUuidAttributeArgs(Attrs);
-      else if (Tok.getIdentifierInfo()->getName() == "RootSignature")
-        ParseMicrosoftRootSignatureAttributeArgs(Attrs);
       else {
         IdentifierInfo *II = Tok.getIdentifierInfo();
         SourceLocation NameLoc = Tok.getLocation();
diff --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp
@@ -7481,9 +7481,6 @@ ProcessDeclAttribute(Sema &S, Scope *scope, Decl *D, const ParsedAttr &AL,
     break;
 
   // HLSL attributes:
-  case ParsedAttr::AT_RootSignature:
-    S.HLSL().handleRootSignatureAttr(D, AL);
-    break;
   case ParsedAttr::AT_HLSLNumThreads:
     S.HLSL().handleNumThreadsAttr(D, AL);
     break;
diff --git a/clang/lib/Sema/SemaHLSL.cpp b/clang/lib/Sema/SemaHLSL.cpp
@@ -29,7 +29,6 @@
 #include "clang/Basic/Specifiers.h"
 #include "clang/Basic/TargetInfo.h"
 #include "clang/Sema/Initialization.h"
-#include "clang/Sema/Lookup.h"
 #include "clang/Sema/ParsedAttr.h"
 #include "clang/Sema/Sema.h"
 #include "clang/Sema/Template.h"
@@ -951,33 +950,6 @@ void SemaHLSL::emitLogicalOperatorFixIt(Expr *LHS, Expr *RHS,
       << NewFnName << FixItHint::CreateReplacement(FullRange, OS.str());
 }
 
-void SemaHLSL::handleRootSignatureAttr(Decl *D, const ParsedAttr &AL) {
-  if (AL.getNumArgs() != 1) {
-    Diag(AL.getLoc(), diag::err_attribute_wrong_number_arguments) << AL << 1;
-    return;
-  }
-
-  IdentifierInfo *Ident = AL.getArgAsIdent(0)->getIdentifierInfo();
-  if (auto *RS = D->getAttr<RootSignatureAttr>()) {
-    if (RS->getSignature() != Ident) {
-      Diag(AL.getLoc(), diag::err_disallowed_duplicate_attribute) << RS;
-      return;
-    }
-
-    Diag(AL.getLoc(), diag::warn_duplicate_attribute_exact) << RS;
-    return;
-  }
-
-  LookupResult R(SemaRef, Ident, SourceLocation(), Sema::LookupOrdinaryName);
-  if (SemaRef.LookupQualifiedName(R, D->getDeclContext()))
-    if (auto *SignatureDecl =
-            dyn_cast<HLSLRootSignatureDecl>(R.getFoundDecl())) {
-      // Perform validation of constructs here
-      D->addAttr(::new (getASTContext())
-                     RootSignatureAttr(getASTContext(), AL, Ident));
-    }
-}
-
 void SemaHLSL::handleNumThreadsAttr(Decl *D, const ParsedAttr &AL) {
   llvm::VersionTuple SMVersion =
       getASTContext().getTargetInfo().getTriple().getOSVersion();
diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -999,11 +999,6 @@ Decl *TemplateDeclInstantiator::VisitHLSLBufferDecl(HLSLBufferDecl *Decl) {
   llvm_unreachable("HLSL buffer declarations cannot be instantiated");
 }
 
-Decl *TemplateDeclInstantiator::VisitHLSLRootSignatureDecl(
-    HLSLRootSignatureDecl *Decl) {
-  llvm_unreachable("HLSL root signature declarations cannot be instantiated");
-}
-
 Decl *
 TemplateDeclInstantiator::VisitPragmaCommentDecl(PragmaCommentDecl *D) {
   llvm_unreachable("pragma comment cannot be instantiated");
diff --git a/clang/lib/Serialization/ASTCommon.cpp b/clang/lib/Serialization/ASTCommon.cpp
@@ -458,7 +458,6 @@ bool serialization::isRedeclarableDeclKind(unsigned Kind) {
   case Decl::RequiresExprBody:
   case Decl::UnresolvedUsingIfExists:
   case Decl::HLSLBuffer:
-  case Decl::HLSLRootSignature:
   case Decl::OpenACCDeclare:
   case Decl::OpenACCRoutine:
     return false;
diff --git a/clang/test/AST/HLSL/RootSignatures-AST.hlsl b/clang/test/AST/HLSL/RootSignatures-AST.hlsl
diff --git a/clang/test/SemaHLSL/RootSignature-err.hlsl b/clang/test/SemaHLSL/RootSignature-err.hlsl
diff --git a/clang/tools/libclang/CIndex.cpp b/clang/tools/libclang/CIndex.cpp
diff --git a/llvm/include/llvm/Frontend/HLSL/HLSLRootSignature.h b/llvm/include/llvm/Frontend/HLSL/HLSLRootSignature.h
diff --git a/llvm/lib/Frontend/HLSL/HLSLRootSignature.cpp b/llvm/lib/Frontend/HLSL/HLSLRootSignature.cpp

Original file line number	Diff line number	Diff line change
`@@ -3093,7 +3093,6 @@ class Parser : public CodeCompletionHandler {`
`3093`	`3093`	`return AttrsParsed;`
`3094`	`3094`	`}`
`3095`	`3095`	`void ParseMicrosoftUuidAttributeArgs(ParsedAttributes &Attrs);`
`3096`		`- void ParseMicrosoftRootSignatureAttributeArgs(ParsedAttributes &Attrs);`
`3097`	`3096`	`void ParseMicrosoftAttributes(ParsedAttributes &Attrs);`
`3098`	`3097`	`bool MaybeParseMicrosoftDeclSpecs(ParsedAttributes &Attrs) {`
`3099`	`3098`	`if (getLangOpts().DeclSpecKeyword && Tok.is(tok::kw___declspec)) {`
Original file line number	Diff line number	Diff line change
`@@ -2,7 +2,6 @@ set(LLVM_LINK_COMPONENTS`
`2`	`2`	`BinaryFormat`
`3`	`3`	`Core`
`4`	`4`	`FrontendOpenMP`
`5`		`- FrontendHLSL`
`6`	`5`	`Support`
`7`	`6`	`TargetParser`
`8`	`7`	`)`