[clang] [Coverage] Introduce the type `CounterPair` for RegionCounterMap. NFC. (PR #112724)

[Jessica Paquette via cfe-commits]

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@@ -1869,7 +1871,10 @@ void CodeGenFunction::EmitAutoVarInit(const AutoVarEmission &emission) {
   // If we are at an unreachable point, we don't need to emit the initializer
   // unless it contains a label.
   if (!HaveInsertPoint()) {
-    if (!Init || !ContainsLabel(Init)) return;
+    if (!Init || !ContainsLabel(Init)) {
+      PGO.markStmtMaybeUsed(Init);
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ornata wrote:

why?

https://github.com/llvm/llvm-project/pull/112724