MCValue: Simplify code with getSubSym

Author: MaskRay

llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp

@@ -3879,9 +3879,9 @@ static void handleIndirectSymViaGOTPCRel(AsmPrinter &AP, const MCExpr **ME,
 
   // Check for a valid base symbol
   const MCSymbol *BaseSym = AP.getSymbol(BaseGV);
-  const MCSymbolRefExpr *SymB = MV.getSymB();
+  const MCSymbol *SymB = MV.getSubSym();
 
-  if (!SymB || BaseSym != &SymB->getSymbol())
+  if (!SymB || BaseSym != SymB)
     return;
 
   // Make sure to match:

llvm/lib/MC/MCAssembler.cpp

@@ -488,10 +488,10 @@ static bool getSymbolOffsetImpl(const MCAssembler &Asm, const MCSymbol &S,
     Offset += ValA;
   }
 
-  const MCSymbolRefExpr *B = Target.getSymB();
+  const MCSymbol *B = Target.getSubSym();
   if (B) {
     uint64_t ValB;
-    if (!getSymbolOffsetImpl(Asm, B->getSymbol(), ReportError, ValB))
+    if (!getSymbolOffsetImpl(Asm, *B, ReportError, ValB))
       return false;
     Offset -= ValB;
   }
@@ -523,11 +523,11 @@ const MCSymbol *MCAssembler::getBaseSymbol(const MCSymbol &Symbol) const {
     return nullptr;
   }
 
-  const MCSymbolRefExpr *RefB = Value.getSymB();
-  if (RefB) {
+  const MCSymbol *SymB = Value.getSubSym();
+  if (SymB) {
     getContext().reportError(
         Expr->getLoc(),
-        Twine("symbol '") + RefB->getSymbol().getName() +
+        Twine("symbol '") + SymB->getName() +
             "' could not be evaluated in a subtraction expression");
     return nullptr;
   }

llvm/lib/MC/MCValue.cpp

@@ -44,12 +44,6 @@ LLVM_DUMP_METHOD void MCValue::dump() const {
 #endif
 
 MCSymbolRefExpr::VariantKind MCValue::getAccessVariant() const {
-  const MCSymbolRefExpr *B = getSymB();
-  if (B) {
-    if (B->getKind() != MCSymbolRefExpr::VK_None)
-      llvm_unreachable("unsupported");
-  }
-
   const MCSymbolRefExpr *A = getSymA();
   if (!A)
     return MCSymbolRefExpr::VK_None;

llvm/lib/MC/XCOFFObjectWriter.cpp

@@ -782,10 +782,9 @@ void XCOFFWriter::recordRelocation(MCAssembler &Asm, const MCFragment *Fragment,
          "Expected containing csect to exist in map.");
   SectionMap[RelocationSec]->Relocations.push_back(Reloc);
 
-  if (!Target.getSymB())
+  const MCSymbol *const SymB = Target.getSubSym();
+  if (!SymB)
     return;
-
-  const MCSymbol *const SymB = &Target.getSymB()->getSymbol();
   if (SymA == SymB)
     report_fatal_error("relocation for opposite term is not yet supported");
 

llvm/lib/Target/AArch64/MCTargetDesc/AArch64MCExpr.cpp

@@ -155,9 +155,6 @@ bool AArch64AuthMCExpr::evaluateAsRelocatableImpl(
   if (!getSubExpr()->evaluateAsRelocatable(Res, Asm))
     return false;
 
-  if (Res.getSymB())
-    report_fatal_error("Auth relocation can't reference two symbols");
-
   Res = MCValue::get(Res.getSymA(), nullptr, Res.getConstant(), getKind());
   return true;
 }

llvm/lib/Target/AArch64/MCTargetDesc/AArch64MachObjectWriter.cpp

@@ -213,11 +213,9 @@ void AArch64MachObjectWriter::recordRelocation(
       // FIXME: x86_64 sets the type to a branch reloc here. Should we do
       // something similar?
     }
-  } else if (Target.getSubSym()) { // A - B + constant
+  } else if (auto *B = Target.getSubSym()) { // A - B + constant
     const MCSymbol *A = &Target.getSymA()->getSymbol();
     const MCSymbol *A_Base = Writer->getAtom(*A);
-
-    const MCSymbol *B = &Target.getSymB()->getSymbol();
     const MCSymbol *B_Base = Writer->getAtom(*B);
 
     // Check for "_foo@got - .", which comes through here as: