[llvm] Clean up external users of GlobalValue::getGUID(StringRef) (PR #129644)

[Owen Rodley via llvm-commits]

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@@ -176,7 +176,7 @@ void MipsSEDAGToDAGISel::processFunctionAfterISel(MachineFunction &MF) {
       case Mips::JAL:
       case Mips::JAL_MM:
         if (MI.getOperand(0).isGlobal() &&
-            MI.getOperand(0).getGlobal()->getGlobalIdentifier() == "_mcount")
+            MI.getOperand(0).getGlobal()->getName() == "_mcount")
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orodley wrote:

Thanks, you're right, this isn't equivalent. I've added a check that it's external before the check on the name, which should make it equivalent now.

By the way, I notice that the other references to `"_mcount"` in this file just check the symbol name, which IIUC would also have the issue of matching a locally defined `"_mcount"` symbol. Not sure if that's a problem here.

> Is there a plan to move way from std::string GlobalValue::getGlobalIdentifier() to getName()?

We want to move away from `getGlobalIdentifier()` insofar as it's used to uniquely identify a global, and towards `getGUID()` instead. Cases like this which care about matching a specific global symbol aren't such a problem.

https://github.com/llvm/llvm-project/pull/129644