[llvm] Insert symbols for prefetch targets read from basic blocks section profile. (PR #168439)

[Matt Arsenault via llvm-commits]

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@@ -1985,7 +1985,33 @@ void AsmPrinter::emitFunctionBody() {
     // Print a label for the basic block.
     emitBasicBlockStart(MBB);
     DenseMap<StringRef, unsigned> MnemonicCounts;
+
+    // Helper to emit a symbol for the prefetch target associated with the given
+    // callsite index in the current MBB.
+    auto EmitPrefetchTargetSymbol = [&](unsigned CallsiteIndex) {
+      MCSymbol *PrefetchTargetSymbol = OutContext.getOrCreateSymbol(
+          Twine("__llvm_prefetch_target_") + MF->getName() + Twine("_") +
+          utostr(MBB.getBBID()->BaseID) + Twine("_") +
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arsenm wrote:

Twine directly supports integer -> string, don't need the utostrs

https://github.com/llvm/llvm-project/pull/168439