[SystemZ] Add indirect reference bit XATTR REFERENCE(INDIRECT) for indirect symbol handling support

llvm/include/llvm/MC/MCGOFFAttributes.h

@@ -82,6 +82,7 @@ struct PRAttr {
 
 // Attributes for ER symbols.
 struct ERAttr {
+  bool IsIndirectReference = false;
   GOFF::ESDExecutable Executable = GOFF::ESD_EXE_Unspecified;
   GOFF::ESDBindingStrength BindingStrength = GOFF::ESD_BST_Strong;
   GOFF::ESDLinkageType Linkage = GOFF::ESD_LT_XPLink;

llvm/include/llvm/MC/MCSymbolGOFF.h

@@ -30,8 +30,9 @@ class MCSymbolGOFF : public MCSymbol {
   GOFF::ESDLinkageType Linkage = GOFF::ESDLinkageType::ESD_LT_XPLink;
 
   enum SymbolFlags : uint16_t {
-    SF_Hidden = 0x01, // Symbol is hidden, aka not exported.
-    SF_Weak = 0x02,   // Symbol is weak.
+    SF_Hidden = 0x01,  // Symbol is hidden, aka not exported.
+    SF_Weak = 0x02,    // Symbol is weak.
+    SF_Indirect = 0x4, // Symbol referenced indirectly.
   };
 
 public:
@@ -53,6 +54,11 @@ class MCSymbolGOFF : public MCSymbol {
   bool isHidden() const { return getFlags() & SF_Hidden; }
   bool isExported() const { return !isHidden(); }
 
+  void setIndirect(bool Value = true) {
+    modifyFlags(Value ? SF_Indirect : 0, SF_Indirect);
+  }
+  bool isIndirect() const { return getFlags() & SF_Indirect; }
+
   void setWeak(bool Value = true) { modifyFlags(Value ? SF_Weak : 0, SF_Weak); }
   bool isWeak() const { return getFlags() & SF_Weak; }
 

llvm/lib/MC/GOFFObjectWriter.cpp

@@ -278,6 +278,7 @@ class GOFFSymbol {
     BehavAttrs.setLinkageType(Attr.Linkage);
     BehavAttrs.setAmode(Attr.Amode);
     BehavAttrs.setBindingScope(Attr.BindingScope);
+    BehavAttrs.setIndirectReference(Attr.IsIndirectReference);
   }
 };
 
@@ -359,9 +360,9 @@ void GOFFWriter::defineLabel(const MCSymbolGOFF &Symbol) {
 
 void GOFFWriter::defineExtern(const MCSymbolGOFF &Symbol) {
   GOFFSymbol ER(Symbol.getName(), Symbol.getIndex(), RootSD->getOrdinal(),
-                GOFF::ERAttr{Symbol.getCodeData(), Symbol.getBindingStrength(),
-                             Symbol.getLinkage(), GOFF::ESD_AMODE_64,
-                             Symbol.getBindingScope()});
+                GOFF::ERAttr{Symbol.isIndirect(), Symbol.getCodeData(),
+                             Symbol.getBindingStrength(), Symbol.getLinkage(),
+                             GOFF::ESD_AMODE_64, Symbol.getBindingScope()});
   writeSymbol(ER);
 }
 

llvm/lib/MC/MCSymbolGOFF.cpp

@@ -24,7 +24,6 @@ bool MCSymbolGOFF::setSymbolAttribute(MCSymbolAttr Attribute) {
   case MCSA_LGlobal:
   case MCSA_Extern:
   case MCSA_Exported:
-  case MCSA_IndirectSymbol:
   case MCSA_Internal:
   case MCSA_LazyReference:
   case MCSA_Local:
@@ -40,6 +39,9 @@ bool MCSymbolGOFF::setSymbolAttribute(MCSymbolAttr Attribute) {
   case MCSA_Memtag:
     return false;
 
+  case MCSA_IndirectSymbol:
+    setIndirect(true);
+    break;
   case MCSA_ELF_TypeFunction:
     setCodeData(GOFF::ESDExecutable::ESD_EXE_CODE);
     break;

llvm/lib/Target/SystemZ/MCTargetDesc/SystemZHLASMAsmStreamer.cpp

@@ -193,17 +193,28 @@ void SystemZHLASMAsmStreamer::emitInstruction(const MCInst &Inst,
   EmitEOL();
 }
 
-static void emitXATTR(raw_ostream &OS, StringRef Name,
+static void emitXATTR(raw_ostream &OS, StringRef Name, bool IsIndirectReference,
                       GOFF::ESDLinkageType Linkage,
                       GOFF::ESDExecutable Executable,
                       GOFF::ESDBindingScope BindingScope) {
   llvm::ListSeparator Sep(",");
   OS << Name << " XATTR ";
   OS << Sep << "LINKAGE(" << (Linkage == GOFF::ESD_LT_OS ? "OS" : "XPLINK")
      << ")";
-  if (Executable != GOFF::ESD_EXE_Unspecified)
-    OS << Sep << "REFERENCE("
-       << (Executable == GOFF::ESD_EXE_CODE ? "CODE" : "DATA") << ")";
+
+  const bool NotUnspecified = (Executable != GOFF::ESD_EXE_Unspecified);
+  if (NotUnspecified || IsIndirectReference) {
+    OS << Sep << "REFERENCE(";
+    llvm::ListSeparator SepRef(",");
+
+    if (NotUnspecified)
+      OS << SepRef << (Executable == GOFF::ESD_EXE_CODE ? "CODE" : "DATA");
+
+    if (IsIndirectReference)
+      OS << SepRef << "INDIRECT";
+
+    OS << ")";
+  }
   if (BindingScope != GOFF::ESD_BSC_Unspecified) {
     OS << Sep << "SCOPE(";
     switch (BindingScope) {
@@ -224,7 +235,6 @@ static void emitXATTR(raw_ostream &OS, StringRef Name,
     }
     OS << ')';
   }
-  OS << '\n';
 }
 
 void SystemZHLASMAsmStreamer::emitLabel(MCSymbol *Symbol, SMLoc Loc) {
@@ -245,8 +255,8 @@ void SystemZHLASMAsmStreamer::emitLabel(MCSymbol *Symbol, SMLoc Loc) {
       EmitEOL();
     }
 
-    emitXATTR(OS, Sym->getName(), Sym->getLinkage(), Sym->getCodeData(),
-              Sym->getBindingScope());
+    emitXATTR(OS, Sym->getName(), Sym->isIndirect(), Sym->getLinkage(),
+              Sym->getCodeData(), Sym->getBindingScope());
     EmitEOL();
   }
 
@@ -355,8 +365,8 @@ void SystemZHLASMAsmStreamer::finishImpl() {
     auto &Sym = static_cast<MCSymbolGOFF &>(const_cast<MCSymbol &>(Symbol));
     OS << " " << (Sym.isWeak() ? "WXTRN" : "EXTRN") << " " << Sym.getName();
     EmitEOL();
-    emitXATTR(OS, Sym.getName(), Sym.getLinkage(), Sym.getCodeData(),
-              Sym.getBindingScope());
+    emitXATTR(OS, Sym.getName(), Sym.isIndirect(), Sym.getLinkage(),
+              Sym.getCodeData(), Sym.getBindingScope());
     EmitEOL();
   }