1 //===- PassRegistry.cpp - Pass Registration Implementation ----------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the PassRegistry, with which passes are registered on
11 // initialization, and supports the PassManager in dependency resolution.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "llvm/PassRegistry.h"
16 #include "llvm/ADT/STLExtras.h"
17 #include "llvm/PassInfo.h"
18 #include "llvm/PassSupport.h"
19 #include "llvm/Support/ManagedStatic.h"
20 #include <cassert>
21 #include <memory>
22 #include <utility>
23 
24 using namespace llvm;
25 
26 // FIXME: We use ManagedStatic to erase the pass registrar on shutdown.
27 // Unfortunately, passes are registered with static ctors, and having
28 // llvm_shutdown clear this map prevents successful resurrection after
29 // llvm_shutdown is run.  Ideally we should find a solution so that we don't
30 // leak the map, AND can still resurrect after shutdown.
31 static ManagedStatic<PassRegistry> PassRegistryObj;
32 PassRegistry *PassRegistry::getPassRegistry() {
33   return &*PassRegistryObj;
34 }
35 
36 //===----------------------------------------------------------------------===//
37 // Accessors
38 //
39 
40 PassRegistry::~PassRegistry() = default;
41 
42 const PassInfo *PassRegistry::getPassInfo(const void *TI) const {
43   sys::SmartScopedReader<true> Guard(Lock);
44   MapType::const_iterator I = PassInfoMap.find(TI);
45   return I != PassInfoMap.end() ? I->second : nullptr;
46 }
47 
48 const PassInfo *PassRegistry::getPassInfo(StringRef Arg) const {
49   sys::SmartScopedReader<true> Guard(Lock);
50   StringMapType::const_iterator I = PassInfoStringMap.find(Arg);
51   return I != PassInfoStringMap.end() ? I->second : nullptr;
52 }
53 
54 //===----------------------------------------------------------------------===//
55 // Pass Registration mechanism
56 //
57 
58 void PassRegistry::registerPass(const PassInfo &PI, bool ShouldFree) {
59   sys::SmartScopedWriter<true> Guard(Lock);
60   bool Inserted =
61       PassInfoMap.insert(std::make_pair(PI.getTypeInfo(), &PI)).second;
62   assert(Inserted && "Pass registered multiple times!");
63   (void)Inserted;
64   PassInfoStringMap[PI.getPassArgument()] = &PI;
65 
66   // Notify any listeners.
67   for (auto *Listener : Listeners)
68     Listener->passRegistered(&PI);
69 
70   if (ShouldFree)
71     ToFree.push_back(std::unique_ptr<const PassInfo>(&PI));
72 }
73 
74 void PassRegistry::enumerateWith(PassRegistrationListener *L) {
75   sys::SmartScopedReader<true> Guard(Lock);
76   for (auto PassInfoPair : PassInfoMap)
77     L->passEnumerate(PassInfoPair.second);
78 }
79 
80 /// Analysis Group Mechanisms.
81 void PassRegistry::registerAnalysisGroup(const void *InterfaceID,
82                                          const void *PassID,
83                                          PassInfo &Registeree, bool isDefault,
84                                          bool ShouldFree) {
85   PassInfo *InterfaceInfo = const_cast<PassInfo *>(getPassInfo(InterfaceID));
86   if (!InterfaceInfo) {
87     // First reference to Interface, register it now.
88     registerPass(Registeree);
89     InterfaceInfo = &Registeree;
90   }
91   assert(Registeree.isAnalysisGroup() &&
92          "Trying to join an analysis group that is a normal pass!");
93 
94   if (PassID) {
95     PassInfo *ImplementationInfo = const_cast<PassInfo *>(getPassInfo(PassID));
96     assert(ImplementationInfo &&
97            "Must register pass before adding to AnalysisGroup!");
98 
99     sys::SmartScopedWriter<true> Guard(Lock);
100 
101     // Make sure we keep track of the fact that the implementation implements
102     // the interface.
103     ImplementationInfo->addInterfaceImplemented(InterfaceInfo);
104 
105     if (isDefault) {
106       assert(InterfaceInfo->getNormalCtor() == nullptr &&
107              "Default implementation for analysis group already specified!");
108       assert(
109           ImplementationInfo->getNormalCtor() &&
110           "Cannot specify pass as default if it does not have a default ctor");
111       InterfaceInfo->setNormalCtor(ImplementationInfo->getNormalCtor());
112     }
113   }
114 
115   if (ShouldFree)
116     ToFree.push_back(std::unique_ptr<const PassInfo>(&Registeree));
117 }
118 
119 void PassRegistry::addRegistrationListener(PassRegistrationListener *L) {
120   sys::SmartScopedWriter<true> Guard(Lock);
121   Listeners.push_back(L);
122 }
123 
124 void PassRegistry::removeRegistrationListener(PassRegistrationListener *L) {
125   sys::SmartScopedWriter<true> Guard(Lock);
126 
127   auto I = llvm::find(Listeners, L);
128   Listeners.erase(I);
129 }
130