Type safe version of MachinePassRegistry

Previous version used type erasure through a `void* (*)()` pointer,
which triggered gcc warning and implied a lot of reinterpret_cast.

This version should make it harder to hit ourselves in the foot.

Differential revision: https://reviews.llvm.org/D54203

(cherry picked from commit 86f8b70f1b7c3f92266197d580f6d86414650997)

Author: serge-sans-paille-qb

include/llvm/CodeGen/MachinePassRegistry.h

@@ -23,21 +23,19 @@
 
 namespace llvm {
 
-typedef void *(*MachinePassCtor)();
-
-
 //===----------------------------------------------------------------------===//
 ///
 /// MachinePassRegistryListener - Listener to adds and removals of nodes in
 /// registration list.
 ///
 //===----------------------------------------------------------------------===//
-class MachinePassRegistryListener {
-  virtual void anchor();
+template <class PassCtorTy> class MachinePassRegistryListener {
+  virtual void anchor() {}
+
 public:
   MachinePassRegistryListener() {}
   virtual ~MachinePassRegistryListener() {}
-  virtual void NotifyAdd(const char *N, MachinePassCtor C, const char *D) = 0;
+  virtual void NotifyAdd(const char *N, PassCtorTy C, const char *D) = 0;
   virtual void NotifyRemove(const char *N) = 0;
 };
 
@@ -47,18 +45,17 @@ class MachinePassRegistryListener {
 /// MachinePassRegistryNode - Machine pass node stored in registration list.
 ///
 //===----------------------------------------------------------------------===//
-class MachinePassRegistryNode {
-
+template <typename PassCtorTy> class MachinePassRegistryNode {
 private:
 
   MachinePassRegistryNode *Next;        // Next function pass in list.
   const char *Name;                     // Name of function pass.
   const char *Description;              // Description string.
-  MachinePassCtor Ctor;                 // Function pass creator.
+  PassCtorTy Ctor;                      // Pass creator.
 
 public:
 
-  MachinePassRegistryNode(const char *N, const char *D, MachinePassCtor C)
+  MachinePassRegistryNode(const char *N, const char *D, PassCtorTy C)
   : Next(nullptr)
   , Name(N)
   , Description(D)
@@ -70,7 +67,7 @@ class MachinePassRegistryNode {
   MachinePassRegistryNode **getNextAddress()    { return &Next; }
   const char *getName()                   const { return Name; }
   const char *getDescription()            const { return Description; }
-  MachinePassCtor getCtor()               const { return Ctor; }
+  PassCtorTy getCtor() const { return Ctor; }
   void setNext(MachinePassRegistryNode *N)      { Next = N; }
 
 };
@@ -81,13 +78,12 @@ class MachinePassRegistryNode {
 /// MachinePassRegistry - Track the registration of machine passes.
 ///
 //===----------------------------------------------------------------------===//
-class MachinePassRegistry {
-
+template <typename PassCtorTy> class MachinePassRegistry {
 private:
-
-  MachinePassRegistryNode *List;        // List of registry nodes.
-  MachinePassCtor Default;              // Default function pass creator.
-  MachinePassRegistryListener* Listener;// Listener for list adds are removes.
+  MachinePassRegistryNode<PassCtorTy> *List; // List of registry nodes.
+  PassCtorTy Default;                        // Default function pass creator.
+  MachinePassRegistryListener<PassCtorTy>
+      *Listener; // Listener for list adds are removes.
 
 public:
 
@@ -96,32 +92,60 @@ class MachinePassRegistry {
 
   // Accessors.
   //
-  MachinePassRegistryNode *getList()                    { return List; }
-  MachinePassCtor getDefault()                          { return Default; }
-  void setDefault(MachinePassCtor C)                    { Default = C; }
-  void setDefault(StringRef Name);
-  void setListener(MachinePassRegistryListener *L)      { Listener = L; }
+  MachinePassRegistryNode<PassCtorTy> *getList() { return List; }
+  PassCtorTy getDefault() { return Default; }
+  void setDefault(PassCtorTy C) { Default = C; }
+  /// setDefault - Set the default constructor by name.
+  void setDefault(StringRef Name) {
+    PassCtorTy Ctor = nullptr;
+    for (MachinePassRegistryNode<PassCtorTy> *R = getList(); R;
+         R = R->getNext()) {
+      if (R->getName() == Name) {
+        Ctor = R->getCtor();
+        break;
+      }
+    }
+    assert(Ctor && "Unregistered pass name");
+    setDefault(Ctor);
+  }
+  void setListener(MachinePassRegistryListener<PassCtorTy> *L) { Listener = L; }
 
   /// Add - Adds a function pass to the registration list.
   ///
-  void Add(MachinePassRegistryNode *Node);
+  void Add(MachinePassRegistryNode<PassCtorTy> *Node) {
+    Node->setNext(List);
+    List = Node;
+    if (Listener)
+      Listener->NotifyAdd(Node->getName(), Node->getCtor(),
+                          Node->getDescription());
+  }
 
   /// Remove - Removes a function pass from the registration list.
   ///
-  void Remove(MachinePassRegistryNode *Node);
-
+  void Remove(MachinePassRegistryNode<PassCtorTy> *Node) {
+    for (MachinePassRegistryNode<PassCtorTy> **I = &List; *I;
+         I = (*I)->getNextAddress()) {
+      if (*I == Node) {
+        if (Listener)
+          Listener->NotifyRemove(Node->getName());
+        *I = (*I)->getNext();
+        break;
+      }
+    }
+  }
 };
 
 
 //===----------------------------------------------------------------------===//
 ///
 /// RegisterPassParser class - Handle the addition of new machine passes.
 ///
-//                                                                           //
-///////////////////////////////////////////////////////////////////////////////
-template<class RegistryClass>
-class RegisterPassParser : public MachinePassRegistryListener,
-                   public cl::parser<typename RegistryClass::FunctionPassCtor> {
+//===----------------------------------------------------------------------===//
+template <class RegistryClass>
+class RegisterPassParser
+    : public MachinePassRegistryListener<
+          typename RegistryClass::FunctionPassCtor>,
+      public cl::parser<typename RegistryClass::FunctionPassCtor> {
 public:
   RegisterPassParser(cl::Option &O)
       : cl::parser<typename RegistryClass::FunctionPassCtor>(O) {}
@@ -144,8 +168,9 @@ class RegisterPassParser : public MachinePassRegistryListener,
 
   // Implement the MachinePassRegistryListener callbacks.
   //
-  void NotifyAdd(const char *N, MachinePassCtor C, const char *D) override {
-    this->addLiteralOption(N, (typename RegistryClass::FunctionPassCtor)C, D);
+  void NotifyAdd(const char *N, typename RegistryClass::FunctionPassCtor C,
+                 const char *D) override {
+    this->addLiteralOption(N, C, D);
   }
   void NotifyRemove(const char *N) override {
     this->removeLiteralOption(N);

include/llvm/CodeGen/MachineScheduler.h

@@ -114,17 +114,19 @@ struct MachineSchedContext {
 
 /// MachineSchedRegistry provides a selection of available machine instruction
 /// schedulers.
-class MachineSchedRegistry : public MachinePassRegistryNode {
+class MachineSchedRegistry
+    : public MachinePassRegistryNode<
+          ScheduleDAGInstrs *(*)(MachineSchedContext *)> {
 public:
   typedef ScheduleDAGInstrs *(*ScheduleDAGCtor)(MachineSchedContext *);
 
   // RegisterPassParser requires a (misnamed) FunctionPassCtor type.
   typedef ScheduleDAGCtor FunctionPassCtor;
 
-  static MachinePassRegistry Registry;
+  static MachinePassRegistry<ScheduleDAGCtor> Registry;
 
   MachineSchedRegistry(const char *N, const char *D, ScheduleDAGCtor C)
-    : MachinePassRegistryNode(N, D, (MachinePassCtor)C) {
+      : MachinePassRegistryNode(N, D, C) {
     Registry.Add(this);
   }
   ~MachineSchedRegistry() { Registry.Remove(this); }
@@ -137,7 +139,8 @@ class MachineSchedRegistry : public MachinePassRegistryNode {
   static MachineSchedRegistry *getList() {
     return (MachineSchedRegistry *)Registry.getList();
   }
-  static void setListener(MachinePassRegistryListener *L) {
+
+  static void setListener(MachinePassRegistryListener<FunctionPassCtor> *L) {
     Registry.setListener(L);
   }
 };

include/llvm/CodeGen/RegAllocRegistry.h

@@ -23,23 +23,20 @@ namespace llvm {
 ///
 /// RegisterRegAlloc class - Track the registration of register allocators.
 ///
-//                                                                           //
-///////////////////////////////////////////////////////////////////////////////
-class RegisterRegAlloc : public MachinePassRegistryNode {
-
+//===----------------------------------------------------------------------===//
+class RegisterRegAlloc : public MachinePassRegistryNode<FunctionPass *(*)()> {
 public:
 
   typedef FunctionPass *(*FunctionPassCtor)();
 
-  static MachinePassRegistry Registry;
+  static MachinePassRegistry<FunctionPassCtor> Registry;
 
   RegisterRegAlloc(const char *N, const char *D, FunctionPassCtor C)
-  : MachinePassRegistryNode(N, D, (MachinePassCtor)C)
-  { 
-     Registry.Add(this); 
+      : MachinePassRegistryNode(N, D, C) {
+    Registry.Add(this);
   }
   ~RegisterRegAlloc() { Registry.Remove(this); }
-  
+
 
   // Accessors.
   //
@@ -49,16 +46,15 @@ class RegisterRegAlloc : public MachinePassRegistryNode {
   static RegisterRegAlloc *getList() {
     return (RegisterRegAlloc *)Registry.getList();
   }
-  static FunctionPassCtor getDefault() {
-    return (FunctionPassCtor)Registry.getDefault();
-  }
-  static void setDefault(FunctionPassCtor C) {
-    Registry.setDefault((MachinePassCtor)C);
-  }
-  static void setListener(MachinePassRegistryListener *L) {
+
+  static FunctionPassCtor getDefault() { return Registry.getDefault(); }
+
+  static void setDefault(FunctionPassCtor C) { Registry.setDefault(C); }
+
+  static void setListener(MachinePassRegistryListener<FunctionPassCtor> *L) {
     Registry.setListener(L);
   }
-  
+
 };
 
 } // end namespace llvm

include/llvm/CodeGen/SchedulerRegistry.h

@@ -32,16 +32,19 @@ class ScheduleDAGSDNodes;
 class SelectionDAG;
 class MachineBasicBlock;
 
-class RegisterScheduler : public MachinePassRegistryNode {
+class RegisterScheduler
+    : public MachinePassRegistryNode<
+          ScheduleDAGSDNodes *(*)(SelectionDAGISel *, CodeGenOpt::Level)> {
 public:
   typedef ScheduleDAGSDNodes *(*FunctionPassCtor)(SelectionDAGISel*,
                                                   CodeGenOpt::Level);
 
-  static MachinePassRegistry Registry;
+  static MachinePassRegistry<FunctionPassCtor> Registry;
 
   RegisterScheduler(const char *N, const char *D, FunctionPassCtor C)
-  : MachinePassRegistryNode(N, D, (MachinePassCtor)C)
-  { Registry.Add(this); }
+      : MachinePassRegistryNode(N, D, C) {
+    Registry.Add(this);
+  }
   ~RegisterScheduler() { Registry.Remove(this); }
 
 
@@ -53,13 +56,8 @@ class RegisterScheduler : public MachinePassRegistryNode {
   static RegisterScheduler *getList() {
     return (RegisterScheduler *)Registry.getList();
   }
-  static FunctionPassCtor getDefault() {
-    return (FunctionPassCtor)Registry.getDefault();
-  }
-  static void setDefault(FunctionPassCtor C) {
-    Registry.setDefault((MachinePassCtor)C);
-  }
-  static void setListener(MachinePassRegistryListener *L) {
+
+  static void setListener(MachinePassRegistryListener<FunctionPassCtor> *L) {
     Registry.setListener(L);
   }
 };

lib/CodeGen/MachinePassRegistry.cpp

@@ -15,41 +15,3 @@
 #include "llvm/CodeGen/MachinePassRegistry.h"
 
 using namespace llvm;
-
-void MachinePassRegistryListener::anchor() { }
-
-/// setDefault - Set the default constructor by name.
-void MachinePassRegistry::setDefault(StringRef Name) {
-  MachinePassCtor Ctor = nullptr;
-  for(MachinePassRegistryNode *R = getList(); R; R = R->getNext()) {
-    if (R->getName() == Name) {
-      Ctor = R->getCtor();
-      break;
-    }
-  }
-  assert(Ctor && "Unregistered pass name");
-  setDefault(Ctor);
-}
-
-/// Add - Adds a function pass to the registration list.
-///
-void MachinePassRegistry::Add(MachinePassRegistryNode *Node) {
-  Node->setNext(List);
-  List = Node;
-  if (Listener) Listener->NotifyAdd(Node->getName(),
-                                    Node->getCtor(),
-                                    Node->getDescription());
-}
-
-
-/// Remove - Removes a function pass from the registration list.
-///
-void MachinePassRegistry::Remove(MachinePassRegistryNode *Node) {
-  for (MachinePassRegistryNode **I = &List; *I; I = (*I)->getNextAddress()) {
-    if (*I == Node) {
-      if (Listener) Listener->NotifyRemove(Node->getName());
-      *I = (*I)->getNext();
-      break;
-    }
-  }
-}

lib/CodeGen/MachineScheduler.cpp

@@ -190,7 +190,8 @@ void PostMachineScheduler::getAnalysisUsage(AnalysisUsage &AU) const {
   MachineFunctionPass::getAnalysisUsage(AU);
 }
 
-MachinePassRegistry MachineSchedRegistry::Registry;
+MachinePassRegistry<MachineSchedRegistry::ScheduleDAGCtor>
+    MachineSchedRegistry::Registry;
 
 /// A dummy default scheduler factory indicates whether the scheduler
 /// is overridden on the command line.

lib/CodeGen/Passes.cpp

@@ -648,7 +648,8 @@ bool TargetPassConfig::getOptimizeRegAlloc() const {
 }
 
 /// RegisterRegAlloc's global Registry tracks allocator registration.
-MachinePassRegistry RegisterRegAlloc::Registry;
+MachinePassRegistry<RegisterRegAlloc::FunctionPassCtor>
+    RegisterRegAlloc::Registry;
 
 /// A dummy default pass factory indicates whether the register allocator is
 /// overridden on the command line.

lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp

@@ -228,7 +228,8 @@ static const bool ViewDAGCombine1 = false,
 /// RegisterScheduler class - Track the registration of instruction schedulers.
 ///
 //===---------------------------------------------------------------------===//
-MachinePassRegistry RegisterScheduler::Registry;
+MachinePassRegistry<RegisterScheduler::FunctionPassCtor>
+    RegisterScheduler::Registry;
 
 //===---------------------------------------------------------------------===//
 ///