[llvm] Move a lot of symbol code to use the symbol string pool (PR #115796)

[Lang Hames via llvm-commits]

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@@ -893,14 +893,14 @@ Error MachOPlatform::MachOPlatformPlugin::
 
   for (auto *Sym : G.defined_symbols()) {
     for (auto &RTSym : RuntimeSymbols) {
-      if (Sym->hasName() && Sym->getName() == RTSym.first) {
+      if (Sym->hasName() && *Sym->getName() == RTSym.first) {
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lhames wrote:

Should be `Sym->getName() == RTSym.first` (assuming we can `SymbolStringPtr`ify RTSym).

https://github.com/llvm/llvm-project/pull/115796