Move vtordisp mode from Attr class to LangOptions.h, NFC

This removes one of the two uses of Attr.h in DeclCXX.h, reducing the
need to include Attr.h as widely. LangOptions is already very popular.

clang/include/clang/AST/DeclCXX.h

@@ -1755,7 +1755,7 @@ public:
 
   /// Controls when vtordisps will be emitted if this record is used as a
   /// virtual base.
-  MSVtorDispAttr::Mode getMSVtorDispMode() const;
+  MSVtorDispMode getMSVtorDispMode() const;
 
   /// Determine whether this lambda expression was known to be dependent
   /// at the time it was created, even if its context does not appear to be

clang/include/clang/Basic/Attr.td

@@ -3021,13 +3021,7 @@ def MSVtorDisp : InheritableAttr {
   let SemaHandler = 0;
 
   let AdditionalMembers = [{
-  enum Mode {
-    Never,
-    ForVBaseOverride,
-    ForVFTable
-  };
-
-  Mode getVtorDispMode() const { return Mode(vdm); }
+  MSVtorDispMode getVtorDispMode() const { return MSVtorDispMode(vdm); }
   }];
   let Documentation = [Undocumented];
 }

clang/include/clang/Basic/LangOptions.def

@@ -304,7 +304,8 @@ BENIGN_LANGOPT(BracketDepth, 32, 256,
 BENIGN_LANGOPT(NumLargeByValueCopy, 32, 0,
         "if non-zero, warn about parameter or return Warn if parameter/return value is larger in bytes than this setting. 0 is no check.")
 VALUE_LANGOPT(MSCompatibilityVersion, 32, 0, "Microsoft Visual C/C++ Version")
-VALUE_LANGOPT(VtorDispMode, 2, 1, "How many vtordisps to insert")
+ENUM_LANGOPT(VtorDispMode, MSVtorDispMode, 2, MSVtorDispMode::ForVBaseOverride,
+             "How many vtordisps to insert")
 
 LANGOPT(ApplePragmaPack, 1, 0, "Apple gcc-compatible #pragma pack handling")
 

clang/include/clang/Basic/LangOptions.h

@@ -44,6 +44,10 @@ protected:
 #include "clang/Basic/LangOptions.def"
 };
 
+/// In the Microsoft ABI, this controls the placement of virtual displacement
+/// members used to implement virtual inheritance.
+enum class MSVtorDispMode { Never, ForVBaseOverride, ForVFTable };
+
 /// Keeps track of the various options that can be
 /// enabled, which controls the dialect of C or C++ that is accepted.
 class LangOptions : public LangOptionsBase {
@@ -91,6 +95,8 @@ public:
     PPTMK_FullGeneralityVirtualInheritance
   };
 
+  using MSVtorDispMode = clang::MSVtorDispMode;
+
   enum DefaultCallingConvention {
     DCC_None,
     DCC_CDecl,

clang/include/clang/Sema/Sema.h

@@ -518,7 +518,7 @@ public:
   ///    structors
   /// 2: Always insert vtordisps to support RTTI on partially constructed
   ///    objects
-  PragmaStack<MSVtorDispAttr::Mode> VtorDispStack;
+  PragmaStack<MSVtorDispMode> VtorDispStack;
   // #pragma pack.
   // Sentinel to represent when the stack is set to mac68k alignment.
   static const unsigned kMac68kAlignmentSentinel = ~0U;
@@ -8960,7 +8960,7 @@ public:
   /// Called on well formed \#pragma vtordisp().
   void ActOnPragmaMSVtorDisp(PragmaMsStackAction Action,
                              SourceLocation PragmaLoc,
-                             MSVtorDispAttr::Mode Value);
+                             MSVtorDispMode Value);
 
   enum PragmaSectionKind {
     PSK_DataSeg,

clang/lib/AST/MicrosoftCXXABI.cpp

@@ -171,10 +171,10 @@ CXXRecordDecl::getMSInheritanceModel() const {
   return IA->getSemanticSpelling();
 }
 
-MSVtorDispAttr::Mode CXXRecordDecl::getMSVtorDispMode() const {
+MSVtorDispMode CXXRecordDecl::getMSVtorDispMode() const {
   if (MSVtorDispAttr *VDA = getAttr<MSVtorDispAttr>())
     return VDA->getVtorDispMode();
-  return MSVtorDispAttr::Mode(getASTContext().getLangOpts().VtorDispMode);
+  return getASTContext().getLangOpts().getVtorDispMode();
 }
 
 // Returns the number of pointer and integer slots used to represent a member

clang/lib/AST/RecordLayoutBuilder.cpp

@@ -2956,7 +2956,7 @@ void MicrosoftRecordLayoutBuilder::computeVtorDispSet(
     const CXXRecordDecl *RD) const {
   // /vd2 or #pragma vtordisp(2): Always use vtordisps for virtual bases with
   // vftables.
-  if (RD->getMSVtorDispMode() == MSVtorDispAttr::ForVFTable) {
+  if (RD->getMSVtorDispMode() == MSVtorDispMode::ForVFTable) {
     for (const CXXBaseSpecifier &Base : RD->vbases()) {
       const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
       const ASTRecordLayout &Layout = Context.getASTRecordLayout(BaseDecl);
@@ -2979,12 +2979,12 @@ void MicrosoftRecordLayoutBuilder::computeVtorDispSet(
   // * A user declared constructor or destructor aren't declared.
   // * #pragma vtordisp(0) or the /vd0 flag are in use.
   if ((!RD->hasUserDeclaredConstructor() && !RD->hasUserDeclaredDestructor()) ||
-      RD->getMSVtorDispMode() == MSVtorDispAttr::Never)
+      RD->getMSVtorDispMode() == MSVtorDispMode::Never)
     return;
   // /vd1 or #pragma vtordisp(1): Try to guess based on whether we think it's
   // possible for a partially constructed object with virtual base overrides to
   // escape a non-trivial constructor.
-  assert(RD->getMSVtorDispMode() == MSVtorDispAttr::ForVBaseOverride);
+  assert(RD->getMSVtorDispMode() == MSVtorDispMode::ForVBaseOverride);
   // Compute a set of base classes which define methods we override.  A virtual
   // base in this set will require a vtordisp.  A virtual base that transitively
   // contains one of these bases as a non-virtual base will also require a

clang/lib/Frontend/CompilerInvocation.cpp

@@ -2716,7 +2716,8 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
                                    OPT_fno_dollars_in_identifiers,
                                    Opts.DollarIdents);
   Opts.PascalStrings = Args.hasArg(OPT_fpascal_strings);
-  Opts.VtorDispMode = getLastArgIntValue(Args, OPT_vtordisp_mode_EQ, 1, Diags);
+  Opts.setVtorDispMode(
+      MSVtorDispMode(getLastArgIntValue(Args, OPT_vtordisp_mode_EQ, 1, Diags)));
   Opts.Borland = Args.hasArg(OPT_fborland_extensions);
   Opts.WritableStrings = Args.hasArg(OPT_fwritable_strings);
   Opts.ConstStrings = Args.hasFlag(OPT_fconst_strings, OPT_fno_const_strings,

clang/lib/Parse/ParsePragma.cpp

@@ -734,7 +734,7 @@ void Parser::HandlePragmaMSVtorDisp() {
   uintptr_t Value = reinterpret_cast<uintptr_t>(Tok.getAnnotationValue());
   Sema::PragmaMsStackAction Action =
       static_cast<Sema::PragmaMsStackAction>((Value >> 16) & 0xFFFF);
-  MSVtorDispAttr::Mode Mode = MSVtorDispAttr::Mode(Value & 0xFFFF);
+  MSVtorDispMode Mode = MSVtorDispMode(Value & 0xFFFF);
   SourceLocation PragmaLoc = ConsumeAnnotationToken();
   Actions.ActOnPragmaMSVtorDisp(Action, PragmaLoc, Mode);
 }

clang/lib/Sema/Sema.cpp

@@ -137,7 +137,7 @@ Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer,
       OriginalLexicalContext(nullptr), MSStructPragmaOn(false),
       MSPointerToMemberRepresentationMethod(
           LangOpts.getMSPointerToMemberRepresentationMethod()),
-      VtorDispStack(MSVtorDispAttr::Mode(LangOpts.VtorDispMode)), PackStack(0),
+      VtorDispStack(LangOpts.getVtorDispMode()), PackStack(0),
       DataSegStack(nullptr), BSSSegStack(nullptr), ConstSegStack(nullptr),
       CodeSegStack(nullptr), CurInitSeg(nullptr), VisContext(nullptr),
       PragmaAttributeCurrentTargetDecl(nullptr),

clang/lib/Sema/SemaAttr.cpp

@@ -80,9 +80,9 @@ void Sema::AddMsStructLayoutForRecord(RecordDecl *RD) {
   // FIXME: We should merge AddAlignmentAttributesForRecord with
   // AddMsStructLayoutForRecord into AddPragmaAttributesForRecord, which takes
   // all active pragmas and applies them as attributes to class definitions.
-  if (VtorDispStack.CurrentValue != getLangOpts().VtorDispMode)
-    RD->addAttr(
-        MSVtorDispAttr::CreateImplicit(Context, VtorDispStack.CurrentValue));
+  if (VtorDispStack.CurrentValue != getLangOpts().getVtorDispMode())
+    RD->addAttr(MSVtorDispAttr::CreateImplicit(
+        Context, unsigned(VtorDispStack.CurrentValue)));
 }
 
 template <typename Attribute>
@@ -416,7 +416,7 @@ void Sema::ActOnPragmaMSPointersToMembers(
 
 void Sema::ActOnPragmaMSVtorDisp(PragmaMsStackAction Action,
                                  SourceLocation PragmaLoc,
-                                 MSVtorDispAttr::Mode Mode) {
+                                 MSVtorDispMode Mode) {
   if (Action & PSK_Pop && VtorDispStack.Stack.empty())
     Diag(PragmaLoc, diag::warn_pragma_pop_failed) << "vtordisp"
                                                   << "stack empty";