[llvm] Centralize prefetch target storage in MachineFunction. (PR #184194)

[Matt Arsenault via llvm-commits]

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@@ -2017,6 +2017,39 @@ void AsmPrinter::handleCallsiteForCallgraph(
   }
 }
 
+/// Helper to emit a symbol for the prefetch target associated with the given
+/// BBID and callsite index.
+void AsmPrinter::emitPrefetchTargetSymbol(unsigned BaseID,
+                                          unsigned CallsiteIndex) {
+  MCSymbol *PrefetchTargetSymbol = OutContext.getOrCreateSymbol(
+      Twine("__llvm_prefetch_target_") + MF->getName() + Twine("_") +
+      Twine(BaseID) + Twine("_") + Twine(static_cast<unsigned>(CallsiteIndex)));
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arsenm wrote:

Unnecessary cast from unsigned to unsigned 

https://github.com/llvm/llvm-project/pull/184194