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

[NAKAMURA Takumi via cfe-commits]

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@@ -122,6 +123,18 @@ class CodeGenPGO {
                                 Address MCDCCondBitmapAddr, llvm::Value *Val,
                                 CodeGenFunction &CGF);
 
+  void markStmtAsUsed(bool Skipped, const Stmt *S) {
+    // Do nothing.
+  }
+
+  void markStmtMaybeUsed(const Stmt *S) {
+    // Do nothing.
+  }
+
+  void verifyCounterMap() {
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chapuni wrote:

Done.

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