[llvm] [AArch64] Transition from MCSymbolRefExpr::VariantKind constants (PR #133214)

[Fangrui Song via llvm-commits]

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@@ -117,13 +117,9 @@ unsigned AArch64ELFObjectWriter::getRelocType(MCContext &Ctx,
   bool IsNC = AArch64MCExpr::isNotChecked(RefKind);
 
   assert((!Target.getSymA() ||
-          Target.getSymA()->getKind() == MCSymbolRefExpr::VK_None ||
-          Target.getSymA()->getKind() == MCSymbolRefExpr::VK_PLT ||
-          Target.getSymA()->getKind() == MCSymbolRefExpr::VK_GOTPCREL) &&
-         "Should only be expression-level modifiers here");
-
-  assert((!Target.getSymB() ||
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MaskRay wrote:

A relocatable expression (`specifier(SymA-SymB+C)`) cannot have a legacy VariantKind on SymB.
Such an expression would have been rejected by `MCAssembler::evaluateFixup` "unsupported subtraction of qualified symbol".

I am actually changing MCValue::SymB from MCSymbolRefExpr to MCSymbol * so that `getSpecifier(Target.getSymB())` would be impossible per the data representation.

https://github.com/llvm/llvm-project/pull/133214