[llvm] [X86Backend] Use GetExternalSymbolSymbol for MO_ExternalSymbol. (PR #133352)

[Nikolay Panchenko via llvm-commits]

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@@ -192,8 +192,15 @@ MCSymbol *X86MCInstLower::GetSymbolFromOperand(const MachineOperand &MO) const {
   }
 
   Name += Suffix;
-  if (!Sym)
-    Sym = Ctx.getOrCreateSymbol(Name);
+  if (!Sym) {
+    // If new MCSymbol needs to be created for
+    // MachineOperand::MO_ExternalSymbol, create it as a symbol
+    // in AsmPrinter's OutContext.
+    if (MO.isSymbol())
+      Sym = AsmPrinter.OutContext.getOrCreateSymbol(Name);
+    else
+      Sym = Ctx.getOrCreateSymbol(Name);
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npanchen wrote:

@efriedma-quic the absence of a fix blocks our pulldown as 50% of tests are failing due to reverted https://github.com/llvm/llvm-project/pull/133291#issuecomment-2759200983 change.

Even though I agree that there might be a better "bulletproof" solution, but is it ok to move forward with Weiwei's fix first and then consider much better solution ? My rationale here is that Weiwei's proposed fix is aligned with what most of the targets are doing now and also there was an interest in community to open source parallel MCLinker. So when it comes to open sourcing there will be more use-cases and we will come back to that topic again.

https://github.com/llvm/llvm-project/pull/133352