[llvm] [NFC] Move DroppedVariableStats to its own file and redesign it to be extensible. (PR #115563)

[Adrian Prantl via llvm-commits]

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@@ -70,36 +83,131 @@ class DroppedVariableStats {
   /// DenseMap of VarIDs and their inlinedAt locations before an optimization
   /// pass has run.
   SmallVector<DenseMap<StringRef, DenseMap<VarID, DILocation *>>> InlinedAts;
+  /// Remove a dropped #dbg_value VarID from all Sets in the
+  /// DroppedVariablesBefore stack.
+  void removeVarFromAllSets(VarID Var, const Function *F) {
+    // Do not remove Var from the last element, it will be popped from the
+    // stack.
+    for (auto &DebugVariablesMap : llvm::drop_end(DebugVariablesStack))
+      DebugVariablesMap[F].DebugVariablesBefore.erase(Var);
+  }
+  /// Return true if \p Scope is the same as \p DbgValScope or a child scope of
+  /// \p DbgValScope, return false otherwise.
+  bool isScopeChildOfOrEqualTo(const DIScope *Scope,
+                               const DIScope *DbgValScope);
+  /// Return true if \p InlinedAt is the same as \p DbgValInlinedAt or part of
+  /// the InlinedAt chain, return false otherwise.
+  bool isInlinedAtChildOfOrEqualTo(const DILocation *InlinedAt,
+                                   const DILocation *DbgValInlinedAt);
 
-  /// Iterate over all Functions in a Module and report any dropped debug
-  /// information. Will call calculateDroppedVarStatsOnFunction on every
-  /// Function.
-  void calculateDroppedVarStatsOnModule(const Module *M, StringRef PassID,
-                                        std::string FuncOrModName,
-                                        std::string PassLevel);
-  /// Iterate over all Instructions in a Function and report any dropped debug
-  /// information.
-  void calculateDroppedVarStatsOnFunction(const Function *F, StringRef PassID,
-                                          std::string FuncOrModName,
-                                          std::string PassLevel);
+  /// Calculate the number of dropped variables in an llvm::Function or
+  /// llvm::MachineFunction and print the relevant information to stdout.
+  void calculateDroppedStatsAndPrint(DebugVariables &DbgVariables,
+                                     StringRef FuncName, StringRef PassID,
+                                     StringRef FuncOrModName,
+                                     StringRef PassLevel);
+
+  /// Check if a \p Var has been dropped or is a false positive.
+  bool checkDroppedStatus(DILocation *DbgLoc, const DIScope *Scope,
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adrian-prantl wrote:

wasDropped()?

https://github.com/llvm/llvm-project/pull/115563