MCSymbolXOFF: Remove classof

The object file format specific derived classes are used in context
where the type is statically known. We don't use isa/dyn_cast and we
want to eliminate MCSymbol::Kind in the base class.

Author: MaskRay

llvm/include/llvm/MC/MCSymbolXCOFF.h

@@ -25,8 +25,6 @@ class MCSymbolXCOFF : public MCSymbol {
   MCSymbolXCOFF(const MCSymbolTableEntry *Name, bool isTemporary)
       : MCSymbol(SymbolKindXCOFF, Name, isTemporary) {}
 
-  static bool classof(const MCSymbol *S) { return S->isXCOFF(); }
-
   enum CodeModel : uint8_t { CM_Small, CM_Large };
 
   static StringRef getUnqualifiedName(StringRef Name) {

llvm/lib/MC/MCAsmStreamer.cpp

@@ -1069,9 +1069,11 @@ void MCAsmStreamer::emitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
 
   // Print symbol's rename (original name contains invalid character(s)) if
   // there is one.
-  MCSymbolXCOFF *XSym = dyn_cast<MCSymbolXCOFF>(Symbol);
-  if (XSym && XSym->hasRename())
-    emitXCOFFRenameDirective(XSym, XSym->getSymbolTableName());
+  if (getContext().isXCOFF()) {
+    auto *XSym = static_cast<MCSymbolXCOFF *>(Symbol);
+    if (XSym && XSym->hasRename())
+      emitXCOFFRenameDirective(XSym, XSym->getSymbolTableName());
+  }
 }
 
 void MCAsmStreamer::emitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,

llvm/lib/MC/MCParser/AsmParser.cpp

@@ -1865,7 +1865,7 @@ bool AsmParser::parseStatement(ParseStatementInfo &Info,
     }
 
     if (MAI.hasSubsectionsViaSymbols() && CFIStartProcLoc &&
-        Sym->isExternal() && !cast<MCSymbolMachO>(Sym)->isAltEntry())
+        Sym->isExternal() && !static_cast<MCSymbolMachO *>(Sym)->isAltEntry())
       return Error(StartTokLoc, "non-private labels cannot appear between "
                                 ".cfi_startproc / .cfi_endproc pairs") &&
              Error(*CFIStartProcLoc, "previous .cfi_startproc was here");

llvm/lib/MC/MCXCOFFStreamer.cpp

@@ -109,7 +109,7 @@ void MCXCOFFStreamer::emitXCOFFRefDirective(const MCSymbol *Symbol) {
 
 void MCXCOFFStreamer::emitXCOFFRenameDirective(const MCSymbol *Name,
                                                StringRef Rename) {
-  const MCSymbolXCOFF *Symbol = cast<const MCSymbolXCOFF>(Name);
+  auto *Symbol = static_cast<const MCSymbolXCOFF *>(Name);
   if (!Symbol->hasRename())
     report_fatal_error("Only explicit .rename is supported for XCOFF.");
 }

llvm/lib/MC/XCOFFObjectWriter.cpp

@@ -690,7 +690,8 @@ void XCOFFWriter::recordRelocation(const MCFragment &F, const MCFixup &Fixup,
   std::tie(Type, SignAndSize) = TargetObjectWriter->getRelocTypeAndSignSize(
       Target, Fixup, Fixup.isPCRel());
 
-  const MCSectionXCOFF *SymASec = getContainingCsect(cast<MCSymbolXCOFF>(SymA));
+  const MCSectionXCOFF *SymASec =
+      getContainingCsect(static_cast<const MCSymbolXCOFF *>(SymA));
   assert(SectionMap.contains(SymASec) &&
          "Expected containing csect to exist in map.");
 
@@ -773,13 +774,13 @@ void XCOFFWriter::recordRelocation(const MCFragment &F, const MCFixup &Fixup,
          "Expected containing csect to exist in map.");
   SectionMap[RelocationSec]->Relocations.push_back(Reloc);
 
-  const MCSymbol *const SymB = Target.getSubSym();
+  auto SymB = static_cast<const MCSymbolXCOFF *>(Target.getSubSym());
   if (!SymB)
     return;
   if (SymA == SymB)
     report_fatal_error("relocation for opposite term is not yet supported");
 
-  const MCSectionXCOFF *SymBSec = getContainingCsect(cast<MCSymbolXCOFF>(SymB));
+  const MCSectionXCOFF *SymBSec = getContainingCsect(SymB);
   assert(SectionMap.contains(SymBSec) &&
          "Expected containing csect to exist in map.");
   if (SymASec == SymBSec)

llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.cpp

@@ -211,7 +211,7 @@ class PPCTargetAsmStreamer : public PPCTargetStreamer {
       : PPCTargetStreamer(S), OS(OS) {}
 
   void emitTCEntry(const MCSymbol &S, PPCMCExpr::Specifier Kind) override {
-    if (const MCSymbolXCOFF *XSym = dyn_cast<MCSymbolXCOFF>(&S)) {
+    if (getContext().isXCOFF()) {
       MCSymbolXCOFF *TCSym =
           static_cast<const MCSectionXCOFF *>(Streamer.getCurrentSectionOnly())
               ->getQualNameSymbol();
@@ -225,10 +225,10 @@ class PPCTargetAsmStreamer : public PPCTargetStreamer {
       if (Kind == PPC::S_AIX_TLSGD || Kind == PPC::S_AIX_TLSGDM ||
           Kind == PPC::S_AIX_TLSIE || Kind == PPC::S_AIX_TLSLE ||
           Kind == PPC::S_AIX_TLSLD || Kind == PPC::S_AIX_TLSML)
-        OS << "\t.tc " << TCSym->getName() << "," << XSym->getName() << "@"
+        OS << "\t.tc " << TCSym->getName() << "," << S.getName() << "@"
            << getContext().getAsmInfo()->getSpecifierName(Kind) << '\n';
       else
-        OS << "\t.tc " << TCSym->getName() << "," << XSym->getName() << '\n';
+        OS << "\t.tc " << TCSym->getName() << "," << S.getName() << '\n';
 
       if (TCSym->hasRename())
         Streamer.emitXCOFFRenameDirective(TCSym, TCSym->getSymbolTableName());

llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp

@@ -3114,7 +3114,7 @@ bool PPCAIXAsmPrinter::doInitialization(Module &M) {
     setCsectAlignment(&G);
     std::optional<CodeModel::Model> OptionalCodeModel = G.getCodeModel();
     if (OptionalCodeModel)
-      setOptionalCodeModel(cast<MCSymbolXCOFF>(getSymbol(&G)),
+      setOptionalCodeModel(static_cast<MCSymbolXCOFF *>(getSymbol(&G)),
                            *OptionalCodeModel);
   }
 
@@ -3141,7 +3141,7 @@ bool PPCAIXAsmPrinter::doInitialization(Module &M) {
     if (GVar) {
       std::optional<CodeModel::Model> OptionalCodeModel = GVar->getCodeModel();
       if (OptionalCodeModel)
-        setOptionalCodeModel(cast<MCSymbolXCOFF>(getSymbol(&Alias)),
+        setOptionalCodeModel(static_cast<MCSymbolXCOFF *>(getSymbol(&Alias)),
                              *OptionalCodeModel);
     }