Merge branch 'amd-staging' of ssh://gerrit-git.amd.com:29418/lightnin…

…g/ec/llvm-project into amd-staging

clang/docs/LanguageExtensions.rst

@@ -1493,6 +1493,7 @@ Conditional ``explicit``                     __cpp_conditional_explicit       C+
 ``if consteval``                             __cpp_if_consteval               C++23         C++20
 ``static operator()``                        __cpp_static_call_operator       C++23         C++03
 Attributes on Lambda-Expressions                                              C++23         C++11
+Attributes on Structured Bindings            __cpp_structured_bindings        C++26         C++03
 ``= delete ("should have a reason");``       __cpp_deleted_function           C++26         C++03
 -------------------------------------------- -------------------------------- ------------- -------------
 Designated initializers (N494)                                                C99           C89

clang/docs/ReleaseNotes.rst

@@ -148,6 +148,8 @@ C++2c Feature Support
 
 - Implemented `P2573R2: = delete("should have a reason"); <https://wg21.link/P2573R2>`_
 
+- Implemented `P0609R3: Attributes for Structured Bindings <https://wg21.link/P0609R3>`_
+
 
 Resolutions to C++ Defect Reports
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

clang/include/clang/Basic/Attr.td

@@ -3211,7 +3211,7 @@ def ObjCRequiresPropertyDefs : InheritableAttr {
 def Unused : InheritableAttr {
   let Spellings = [CXX11<"", "maybe_unused", 201603>, GCC<"unused">,
                    C23<"", "maybe_unused", 202106>];
-  let Subjects = SubjectList<[Var, ObjCIvar, Type, Enum, EnumConstant, Label,
+  let Subjects = SubjectList<[Var, Binding, ObjCIvar, Type, Enum, EnumConstant, Label,
                               Field, ObjCMethod, FunctionLike]>;
   let Documentation = [WarnMaybeUnusedDocs];
 }

clang/include/clang/Basic/DiagnosticParseKinds.td

@@ -478,6 +478,15 @@ def ext_decomp_decl_empty : ExtWarn<
   "ISO C++17 does not allow a decomposition group to be empty">,
   InGroup<DiagGroup<"empty-decomposition">>;
 
+// C++26 structured bindings
+def ext_decl_attrs_on_binding : ExtWarn<
+  "an attribute specifier sequence attached to a structured binding declaration "
+  "is a C++2c extension">, InGroup<CXX26>;
+def warn_cxx23_compat_decl_attrs_on_binding : Warning<
+  "an attribute specifier sequence attached to a structured binding declaration "
+  "is incompatible with C++ standards before C++2c">,
+  InGroup<CXXPre26Compat>, DefaultIgnore;
+
 /// Objective-C parser diagnostics
 def err_expected_minus_or_plus : Error<
   "method type specifier must start with '-' or '+'">;

clang/include/clang/Sema/DeclSpec.h

@@ -36,6 +36,7 @@
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/ErrorHandling.h"
+#include <optional>
 
 namespace clang {
   class ASTContext;
@@ -1790,6 +1791,7 @@ class DecompositionDeclarator {
   struct Binding {
     IdentifierInfo *Name;
     SourceLocation NameLoc;
+    std::optional<ParsedAttributes> Attrs;
   };
 
 private:
@@ -2339,10 +2341,10 @@ class Declarator {
   }
 
   /// Set the decomposition bindings for this declarator.
-  void
-  setDecompositionBindings(SourceLocation LSquareLoc,
-                           ArrayRef<DecompositionDeclarator::Binding> Bindings,
-                           SourceLocation RSquareLoc);
+  void setDecompositionBindings(
+      SourceLocation LSquareLoc,
+      MutableArrayRef<DecompositionDeclarator::Binding> Bindings,
+      SourceLocation RSquareLoc);
 
   /// AddTypeInfo - Add a chunk to this declarator. Also extend the range to
   /// EndLoc, which should be the last token of the chunk.

clang/include/clang/Sema/ParsedAttr.h

@@ -948,6 +948,7 @@ class ParsedAttributes : public ParsedAttributesView {
   ParsedAttributes(AttributeFactory &factory) : pool(factory) {}
   ParsedAttributes(const ParsedAttributes &) = delete;
   ParsedAttributes &operator=(const ParsedAttributes &) = delete;
+  ParsedAttributes(ParsedAttributes &&G) = default;
 
   AttributePool &getPool() const { return pool; }
 

clang/lib/AST/DeclBase.cpp

@@ -1115,7 +1115,9 @@ int64_t Decl::getID() const {
 
 const FunctionType *Decl::getFunctionType(bool BlocksToo) const {
   QualType Ty;
-  if (const auto *D = dyn_cast<ValueDecl>(this))
+  if (const auto *D = dyn_cast<BindingDecl>(this))
+    return nullptr;
+  else if (const auto *D = dyn_cast<ValueDecl>(this))
     Ty = D->getType();
   else if (const auto *D = dyn_cast<TypedefNameDecl>(this))
     Ty = D->getUnderlyingType();

clang/lib/Format/FormatToken.h

@@ -1623,10 +1623,10 @@ struct AdditionalKeywords {
   IdentifierInfo *kw_then;
 
   /// Returns \c true if \p Tok is a keyword or an identifier.
-  bool isWordLike(const FormatToken &Tok) const {
+  bool isWordLike(const FormatToken &Tok, bool IsVerilog = true) const {
     // getIdentifierinfo returns non-null for keywords as well as identifiers.
     return Tok.Tok.getIdentifierInfo() &&
-           !Tok.isOneOf(kw_verilogHash, kw_verilogHashHash, kw_apostrophe);
+           (!IsVerilog || !isVerilogKeywordSymbol(Tok));
   }
 
   /// Returns \c true if \p Tok is a true JavaScript identifier, returns
@@ -1755,6 +1755,10 @@ struct AdditionalKeywords {
     }
   }
 
+  bool isVerilogKeywordSymbol(const FormatToken &Tok) const {
+    return Tok.isOneOf(kw_verilogHash, kw_verilogHashHash, kw_apostrophe);
+  }
+
   bool isVerilogWordOperator(const FormatToken &Tok) const {
     return Tok.isOneOf(kw_before, kw_intersect, kw_dist, kw_iff, kw_inside,
                        kw_with);

clang/lib/Format/TokenAnnotator.cpp

@@ -4780,9 +4780,14 @@ bool TokenAnnotator::spaceRequiredBefore(const AnnotatedLine &Line,
   if (Left.Finalized)
     return Right.hasWhitespaceBefore();
 
+  const bool IsVerilog = Style.isVerilog();
+  assert(!IsVerilog || !IsCpp);
+
   // Never ever merge two words.
-  if (Keywords.isWordLike(Right) && Keywords.isWordLike(Left))
+  if (Keywords.isWordLike(Right, IsVerilog) &&
+      Keywords.isWordLike(Left, IsVerilog)) {
     return true;
+  }
 
   // Leave a space between * and /* to avoid C4138 `comment end` found outside
   // of comment.
@@ -5063,12 +5068,10 @@ bool TokenAnnotator::spaceRequiredBefore(const AnnotatedLine &Line,
         Right.is(TT_TemplateOpener)) {
       return true;
     }
-  } else if (Style.isVerilog()) {
+  } else if (IsVerilog) {
     // An escaped identifier ends with whitespace.
-    if (Style.isVerilog() && Left.is(tok::identifier) &&
-        Left.TokenText[0] == '\\') {
+    if (Left.is(tok::identifier) && Left.TokenText[0] == '\\')
       return true;
-    }
     // Add space between things in a primitive's state table unless in a
     // transition like `(0?)`.
     if ((Left.is(TT_VerilogTableItem) &&

clang/lib/Format/WhitespaceManager.cpp

@@ -131,6 +131,7 @@ void WhitespaceManager::calculateLineBreakInformation() {
   for (unsigned I = 1, e = Changes.size(); I != e; ++I) {
     auto &C = Changes[I];
     auto &P = Changes[I - 1];
+    auto &PrevTokLength = P.TokenLength;
     SourceLocation OriginalWhitespaceStart =
         C.OriginalWhitespaceRange.getBegin();
     SourceLocation PreviousOriginalWhitespaceEnd =
@@ -169,21 +170,23 @@ void WhitespaceManager::calculateLineBreakInformation() {
     // line of the token.
     auto NewlinePos = Text.find_first_of('\n');
     if (NewlinePos == StringRef::npos) {
-      P.TokenLength = OriginalWhitespaceStartOffset -
+      PrevTokLength = OriginalWhitespaceStartOffset -
                       PreviousOriginalWhitespaceEndOffset +
                       C.PreviousLinePostfix.size() + P.CurrentLinePrefix.size();
+      if (!P.IsInsideToken)
+        PrevTokLength = std::min(PrevTokLength, P.Tok->ColumnWidth);
     } else {
-      P.TokenLength = NewlinePos + P.CurrentLinePrefix.size();
+      PrevTokLength = NewlinePos + P.CurrentLinePrefix.size();
     }
 
     // If there are multiple changes in this token, sum up all the changes until
     // the end of the line.
     if (P.IsInsideToken && P.NewlinesBefore == 0)
-      LastOutsideTokenChange->TokenLength += P.TokenLength + P.Spaces;
+      LastOutsideTokenChange->TokenLength += PrevTokLength + P.Spaces;
     else
       LastOutsideTokenChange = &P;
 
-    C.PreviousEndOfTokenColumn = P.StartOfTokenColumn + P.TokenLength;
+    C.PreviousEndOfTokenColumn = P.StartOfTokenColumn + PrevTokLength;
 
     P.IsTrailingComment =
         (C.NewlinesBefore > 0 || C.Tok->is(tok::eof) ||

clang/lib/Frontend/InitPreprocessor.cpp

@@ -703,7 +703,7 @@ static void InitializeCPlusPlusFeatureTestMacros(const LangOptions &LangOpts,
     Builder.defineMacro("__cpp_nested_namespace_definitions", "201411L");
     Builder.defineMacro("__cpp_variadic_using", "201611L");
     Builder.defineMacro("__cpp_aggregate_bases", "201603L");
-    Builder.defineMacro("__cpp_structured_bindings", "201606L");
+    Builder.defineMacro("__cpp_structured_bindings", "202403L");
     Builder.defineMacro("__cpp_nontype_template_args",
                         "201411L"); // (not latest)
     Builder.defineMacro("__cpp_fold_expressions", "201603L");

clang/lib/Parse/ParseDecl.cpp

@@ -7038,18 +7038,23 @@ void Parser::ParseDirectDeclarator(Declarator &D) {
 void Parser::ParseDecompositionDeclarator(Declarator &D) {
   assert(Tok.is(tok::l_square));
 
+  TentativeParsingAction PA(*this);
+  BalancedDelimiterTracker T(*this, tok::l_square);
+  T.consumeOpen();
+
+  if (isCXX11AttributeSpecifier())
+    DiagnoseAndSkipCXX11Attributes();
+
   // If this doesn't look like a structured binding, maybe it's a misplaced
   // array declarator.
-  // FIXME: Consume the l_square first so we don't need extra lookahead for
-  // this.
-  if (!(NextToken().is(tok::identifier) &&
-        GetLookAheadToken(2).isOneOf(tok::comma, tok::r_square)) &&
-      !(NextToken().is(tok::r_square) &&
-        GetLookAheadToken(2).isOneOf(tok::equal, tok::l_brace)))
+  if (!(Tok.is(tok::identifier) &&
+        NextToken().isOneOf(tok::comma, tok::r_square, tok::kw_alignas,
+                            tok::l_square)) &&
+      !(Tok.is(tok::r_square) &&
+        NextToken().isOneOf(tok::equal, tok::l_brace))) {
+    PA.Revert();
     return ParseMisplacedBracketDeclarator(D);
-
-  BalancedDelimiterTracker T(*this, tok::l_square);
-  T.consumeOpen();
+  }
 
   SmallVector<DecompositionDeclarator::Binding, 32> Bindings;
   while (Tok.isNot(tok::r_square)) {
@@ -7074,13 +7079,27 @@ void Parser::ParseDecompositionDeclarator(Declarator &D) {
       }
     }
 
+    if (isCXX11AttributeSpecifier())
+      DiagnoseAndSkipCXX11Attributes();
+
     if (Tok.isNot(tok::identifier)) {
       Diag(Tok, diag::err_expected) << tok::identifier;
       break;
     }
 
-    Bindings.push_back({Tok.getIdentifierInfo(), Tok.getLocation()});
+    IdentifierInfo *II = Tok.getIdentifierInfo();
+    SourceLocation Loc = Tok.getLocation();
     ConsumeToken();
+
+    ParsedAttributes Attrs(AttrFactory);
+    if (isCXX11AttributeSpecifier()) {
+      Diag(Tok, getLangOpts().CPlusPlus26
+                    ? diag::warn_cxx23_compat_decl_attrs_on_binding
+                    : diag::ext_decl_attrs_on_binding);
+      MaybeParseCXX11Attributes(Attrs);
+    }
+
+    Bindings.push_back({II, Loc, std::move(Attrs)});
   }
 
   if (Tok.isNot(tok::r_square))
@@ -7095,6 +7114,8 @@ void Parser::ParseDecompositionDeclarator(Declarator &D) {
     T.consumeClose();
   }
 
+  PA.Commit();
+
   return D.setDecompositionBindings(T.getOpenLocation(), Bindings,
                                     T.getCloseLocation());
 }

clang/lib/Sema/DeclSpec.cpp

@@ -293,7 +293,7 @@ DeclaratorChunk DeclaratorChunk::getFunction(bool hasProto,
 
 void Declarator::setDecompositionBindings(
     SourceLocation LSquareLoc,
-    ArrayRef<DecompositionDeclarator::Binding> Bindings,
+    MutableArrayRef<DecompositionDeclarator::Binding> Bindings,
     SourceLocation RSquareLoc) {
   assert(!hasName() && "declarator given multiple names!");
 
@@ -317,7 +317,7 @@ void Declarator::setDecompositionBindings(
           new DecompositionDeclarator::Binding[Bindings.size()];
       BindingGroup.DeleteBindings = true;
     }
-    std::uninitialized_copy(Bindings.begin(), Bindings.end(),
+    std::uninitialized_move(Bindings.begin(), Bindings.end(),
                             BindingGroup.Bindings);
   }
 }

clang/lib/Sema/SemaDecl.cpp

@@ -1974,7 +1974,7 @@ static bool ShouldDiagnoseUnusedDecl(const LangOptions &LangOpts,
     // it is, by the bindings' expressions).
     bool IsAllPlaceholders = true;
     for (const auto *BD : DD->bindings()) {
-      if (BD->isReferenced())
+      if (BD->isReferenced() || BD->hasAttr<UnusedAttr>())
         return false;
       IsAllPlaceholders = IsAllPlaceholders && BD->isPlaceholderVar(LangOpts);
     }

clang/lib/Sema/SemaDeclCXX.cpp

@@ -910,6 +910,8 @@ Sema::ActOnDecompositionDeclarator(Scope *S, Declarator &D,
 
     auto *BD = BindingDecl::Create(Context, DC, B.NameLoc, VarName);
 
+    ProcessDeclAttributeList(S, BD, *B.Attrs);
+
     // Find the shadowed declaration before filtering for scope.
     NamedDecl *ShadowedDecl = D.getCXXScopeSpec().isEmpty()
                                   ? getShadowedDeclaration(BD, Previous)

clang/test/Driver/amdgpu-toolchain.c

@@ -27,4 +27,4 @@
 
 // RUN: %clang -### --target=amdgcn-amd-amdhsa -mcpu=gfx906 -nogpulib \
 // RUN:   -fuse-ld=ld %s 2>&1 | FileCheck -check-prefixes=LD %s
-// LD: ld.lld"
+// LD: ld.lld

clang/test/Lexer/cxx-features.cpp

@@ -222,7 +222,7 @@
 #error "wrong value for __cpp_aggregate_bases"
 #endif
 
-#if check(structured_bindings, 0, 0, 0, 201606, 201606, 201606, 201606)
+#if check(structured_bindings, 0, 0, 0, 202403L, 202403L, 202403L, 202403L)
 #error "wrong value for __cpp_structured_bindings"
 #endif
 

clang/test/Misc/cc1as-relax-all.s

@@ -0,0 +1,13 @@
+// REQUIRES: x86-registered-target
+// RUN: %clang -cc1as -triple x86_64 -filetype obj -mrelax-all %s -o %t.o
+// RUN: llvm-objdump -d %t.o | FileCheck %s
+
+// CHECK:      <.text>:
+// CHECK-NEXT:   0: e9 06 00 00 00                jmp     0xb <foo>
+// CHECK-NEXT:   5: 0f 84 00 00 00 00             je      0xb <foo>
+// CHECK-EMPTY:
+
+jmp foo
+je foo
+
+foo: ret