include/llvm/CodeGen/MachinePassRegistry.h

   1 //===- llvm/CodeGen/MachinePassRegistry.h -----------------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file contains the mechanics for machine function pass registries.  A
  10 // function pass registry (MachinePassRegistry) is auto filled by the static
  11 // constructors of MachinePassRegistryNode.  Further there is a command line
  12 // parser (RegisterPassParser) which listens to each registry for additions
  13 // and deletions, so that the appropriate command option is updated.
  14 //
  15 //===----------------------------------------------------------------------===//
  16
  17 #ifndef LLVM_CODEGEN_MACHINEPASSREGISTRY_H
  18 #define LLVM_CODEGEN_MACHINEPASSREGISTRY_H
  19
  20 #include "llvm/ADT/StringRef.h"
  21 #include "llvm/CodeGen/Passes.h"
  22 #include "llvm/Support/CommandLine.h"
  23
  24 namespace llvm {
  25
  26 //===----------------------------------------------------------------------===//
  27 ///
  28 /// MachinePassRegistryListener - Listener to adds and removals of nodes in
  29 /// registration list.
  30 ///
  31 //===----------------------------------------------------------------------===//
  32 template <class PassCtorTy> class MachinePassRegistryListener {
  33   virtual void anchor() {}
  34
  35 public:
  36   MachinePassRegistryListener() = default;
  37   virtual ~MachinePassRegistryListener() = default;
  38
  39   virtual void NotifyAdd(StringRef N, PassCtorTy C, StringRef D) = 0;
  40   virtual void NotifyRemove(StringRef N) = 0;
  41 };
  42
  43 //===----------------------------------------------------------------------===//
  44 ///
  45 /// MachinePassRegistryNode - Machine pass node stored in registration list.
  46 ///
  47 //===----------------------------------------------------------------------===//
  48 template <typename PassCtorTy> class MachinePassRegistryNode {
  49 private:
  50   MachinePassRegistryNode *Next = nullptr; // Next function pass in list.
  51   StringRef Name;                       // Name of function pass.
  52   StringRef Description;                // Description string.
  53   PassCtorTy Ctor;                      // Pass creator.
  54
  55 public:
  56   MachinePassRegistryNode(const char *N, const char *D, PassCtorTy C)
  57       : Name(N), Description(D), Ctor(C) {}
  58
  59   // Accessors
  60   MachinePassRegistryNode *getNext()      const { return Next; }
  61   MachinePassRegistryNode **getNextAddress()    { return &Next; }
  62   StringRef getName()                   const { return Name; }
  63   StringRef getDescription()            const { return Description; }
  64   PassCtorTy getCtor() const { return Ctor; }
  65   void setNext(MachinePassRegistryNode *N)      { Next = N; }
  66 };
  67
  68 //===----------------------------------------------------------------------===//
  69 ///
  70 /// MachinePassRegistry - Track the registration of machine passes.
  71 ///
  72 //===----------------------------------------------------------------------===//
  73 template <typename PassCtorTy> class MachinePassRegistry {
  74 private:
  75   MachinePassRegistryNode<PassCtorTy> *List; // List of registry nodes.
  76   PassCtorTy Default;                        // Default function pass creator.
  77   MachinePassRegistryListener<PassCtorTy>
  78       *Listener; // Listener for list adds are removes.
  79
  80 public:
  81   // NO CONSTRUCTOR - we don't want static constructor ordering to mess
  82   // with the registry.
  83
  84   // Accessors.
  85   //
  86   MachinePassRegistryNode<PassCtorTy> *getList() { return List; }
  87   PassCtorTy getDefault() { return Default; }
  88   void setDefault(PassCtorTy C) { Default = C; }
  89   /// setDefault - Set the default constructor by name.
  90   void setDefault(StringRef Name) {
  91     PassCtorTy Ctor = nullptr;
  92     for (MachinePassRegistryNode<PassCtorTy> *R = getList(); R;
  93          R = R->getNext()) {
  94       if (R->getName() == Name) {
  95         Ctor = R->getCtor();
  96         break;
  97       }
  98     }
  99     assert(Ctor && "Unregistered pass name");
 100     setDefault(Ctor);
 101   }
 102   void setListener(MachinePassRegistryListener<PassCtorTy> *L) { Listener = L; }
 103
 104   /// Add - Adds a function pass to the registration list.
 105   ///
 106   void Add(MachinePassRegistryNode<PassCtorTy> *Node) {
 107     Node->setNext(List);
 108     List = Node;
 109     if (Listener)
 110       Listener->NotifyAdd(Node->getName(), Node->getCtor(),
 111                           Node->getDescription());
 112   }
 113
 114   /// Remove - Removes a function pass from the registration list.
 115   ///
 116   void Remove(MachinePassRegistryNode<PassCtorTy> *Node) {
 117     for (MachinePassRegistryNode<PassCtorTy> **I = &List; *I;
 118          I = (*I)->getNextAddress()) {
 119       if (*I == Node) {
 120         if (Listener)
 121           Listener->NotifyRemove(Node->getName());
 122         *I = (*I)->getNext();
 123         break;
 124       }
 125     }
 126   }
 127 };
 128
 129 //===----------------------------------------------------------------------===//
 130 ///
 131 /// RegisterPassParser class - Handle the addition of new machine passes.
 132 ///
 133 //===----------------------------------------------------------------------===//
 134 template <class RegistryClass>
 135 class RegisterPassParser
 136     : public MachinePassRegistryListener<
 137           typename RegistryClass::FunctionPassCtor>,
 138       public cl::parser<typename RegistryClass::FunctionPassCtor> {
 139 public:
 140   RegisterPassParser(cl::Option &O)
 141       : cl::parser<typename RegistryClass::FunctionPassCtor>(O) {}
 142   ~RegisterPassParser() override { RegistryClass::setListener(nullptr); }
 143
 144   void initialize() {
 145     cl::parser<typename RegistryClass::FunctionPassCtor>::initialize();
 146
 147     // Add existing passes to option.
 148     for (RegistryClass *Node = RegistryClass::getList();
 149          Node; Node = Node->getNext()) {
 150       this->addLiteralOption(Node->getName(),
 151                       (typename RegistryClass::FunctionPassCtor)Node->getCtor(),
 152                              Node->getDescription());
 153     }
 154
 155     // Make sure we listen for list changes.
 156     RegistryClass::setListener(this);
 157   }
 158
 159   // Implement the MachinePassRegistryListener callbacks.
 160   void NotifyAdd(StringRef N, typename RegistryClass::FunctionPassCtor C,
 161                  StringRef D) override {
 162     this->addLiteralOption(N, C, D);
 163   }
 164   void NotifyRemove(StringRef N) override {
 165     this->removeLiteralOption(N);
 166   }
 167 };
 168
 169 } // end namespace llvm
 170
 171 #endif // LLVM_CODEGEN_MACHINEPASSREGISTRY_H