1 //===-- GCMetadata.cpp - Garbage collector metadata -----------------------===//
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 GCFunctionInfo class and GCModuleInfo pass.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm/CodeGen/GCMetadata.h"
15 #include "llvm/CodeGen/GCStrategy.h"
16 #include "llvm/CodeGen/MachineFrameInfo.h"
17 #include "llvm/Pass.h"
18 #include "llvm/CodeGen/Passes.h"
19 #include "llvm/Function.h"
20 #include "llvm/MC/MCSymbol.h"
21 #include "llvm/Support/Debug.h"
22 #include "llvm/Support/ErrorHandling.h"
23 #include "llvm/Support/raw_ostream.h"
24 using namespace llvm;
25 
26 namespace {
27 
28   class Printer : public FunctionPass {
29     static char ID;
30     raw_ostream &OS;
31 
32   public:
33     Printer() : FunctionPass(&ID), OS(errs()) {}
34     explicit Printer(raw_ostream &OS) : FunctionPass(&ID), OS(OS) {}
35 
36 
37     const char *getPassName() const;
38     void getAnalysisUsage(AnalysisUsage &AU) const;
39 
40     bool runOnFunction(Function &F);
41   };
42 
43   class Deleter : public FunctionPass {
44     static char ID;
45 
46   public:
47     Deleter();
48 
49     const char *getPassName() const;
50     void getAnalysisUsage(AnalysisUsage &AU) const;
51 
52     bool runOnFunction(Function &F);
53     bool doFinalization(Module &M);
54   };
55 
56 }
57 
58 static RegisterPass<GCModuleInfo>
59 X("collector-metadata", "Create Garbage Collector Module Metadata");
60 
61 // -----------------------------------------------------------------------------
62 
63 GCFunctionInfo::GCFunctionInfo(const Function &F, GCStrategy &S)
64   : F(F), S(S), FrameSize(~0LL) {}
65 
66 GCFunctionInfo::~GCFunctionInfo() {}
67 
68 // -----------------------------------------------------------------------------
69 
70 char GCModuleInfo::ID = 0;
71 
72 GCModuleInfo::GCModuleInfo()
73   : ImmutablePass(&ID) {}
74 
75 GCModuleInfo::~GCModuleInfo() {
76   clear();
77 }
78 
79 GCStrategy *GCModuleInfo::getOrCreateStrategy(const Module *M,
80                                               const std::string &Name) {
81   strategy_map_type::iterator NMI = StrategyMap.find(Name);
82   if (NMI != StrategyMap.end())
83     return NMI->getValue();
84 
85   for (GCRegistry::iterator I = GCRegistry::begin(),
86                             E = GCRegistry::end(); I != E; ++I) {
87     if (Name == I->getName()) {
88       GCStrategy *S = I->instantiate();
89       S->M = M;
90       S->Name = Name;
91       StrategyMap.GetOrCreateValue(Name).setValue(S);
92       StrategyList.push_back(S);
93       return S;
94     }
95   }
96 
97   dbgs() << "unsupported GC: " << Name << "\n";
98   llvm_unreachable(0);
99 }
100 
101 GCFunctionInfo &GCModuleInfo::getFunctionInfo(const Function &F) {
102   assert(!F.isDeclaration() && "Can only get GCFunctionInfo for a definition!");
103   assert(F.hasGC());
104 
105   finfo_map_type::iterator I = FInfoMap.find(&F);
106   if (I != FInfoMap.end())
107     return *I->second;
108 
109   GCStrategy *S = getOrCreateStrategy(F.getParent(), F.getGC());
110   GCFunctionInfo *GFI = S->insertFunctionInfo(F);
111   FInfoMap[&F] = GFI;
112   return *GFI;
113 }
114 
115 void GCModuleInfo::clear() {
116   FInfoMap.clear();
117   StrategyMap.clear();
118 
119   for (iterator I = begin(), E = end(); I != E; ++I)
120     delete *I;
121   StrategyList.clear();
122 }
123 
124 // -----------------------------------------------------------------------------
125 
126 char Printer::ID = 0;
127 
128 FunctionPass *llvm::createGCInfoPrinter(raw_ostream &OS) {
129   return new Printer(OS);
130 }
131 
132 
133 const char *Printer::getPassName() const {
134   return "Print Garbage Collector Information";
135 }
136 
137 void Printer::getAnalysisUsage(AnalysisUsage &AU) const {
138   FunctionPass::getAnalysisUsage(AU);
139   AU.setPreservesAll();
140   AU.addRequired<GCModuleInfo>();
141 }
142 
143 static const char *DescKind(GC::PointKind Kind) {
144   switch (Kind) {
145     default: llvm_unreachable("Unknown GC point kind");
146     case GC::Loop:     return "loop";
147     case GC::Return:   return "return";
148     case GC::PreCall:  return "pre-call";
149     case GC::PostCall: return "post-call";
150   }
151 }
152 
153 bool Printer::runOnFunction(Function &F) {
154   if (F.hasGC()) return false;
155 
156   GCFunctionInfo *FD = &getAnalysis<GCModuleInfo>().getFunctionInfo(F);
157 
158   OS << "GC roots for " << FD->getFunction().getNameStr() << ":\n";
159   for (GCFunctionInfo::roots_iterator RI = FD->roots_begin(),
160                                       RE = FD->roots_end(); RI != RE; ++RI)
161     OS << "\t" << RI->Num << "\t" << RI->StackOffset << "[sp]\n";
162 
163   OS << "GC safe points for " << FD->getFunction().getNameStr() << ":\n";
164   for (GCFunctionInfo::iterator PI = FD->begin(),
165                                 PE = FD->end(); PI != PE; ++PI) {
166 
167     OS << "\t" << PI->Label->getName() << ": "
168        << DescKind(PI->Kind) << ", live = {";
169 
170     for (GCFunctionInfo::live_iterator RI = FD->live_begin(PI),
171                                        RE = FD->live_end(PI);;) {
172       OS << " " << RI->Num;
173       if (++RI == RE)
174         break;
175       OS << ",";
176     }
177 
178     OS << " }\n";
179   }
180 
181   return false;
182 }
183 
184 // -----------------------------------------------------------------------------
185 
186 char Deleter::ID = 0;
187 
188 FunctionPass *llvm::createGCInfoDeleter() {
189   return new Deleter();
190 }
191 
192 Deleter::Deleter() : FunctionPass(&ID) {}
193 
194 const char *Deleter::getPassName() const {
195   return "Delete Garbage Collector Information";
196 }
197 
198 void Deleter::getAnalysisUsage(AnalysisUsage &AU) const {
199   AU.setPreservesAll();
200   AU.addRequired<GCModuleInfo>();
201 }
202 
203 bool Deleter::runOnFunction(Function &MF) {
204   return false;
205 }
206 
207 bool Deleter::doFinalization(Module &M) {
208   GCModuleInfo *GMI = getAnalysisIfAvailable<GCModuleInfo>();
209   assert(GMI && "Deleter didn't require GCModuleInfo?!");
210   GMI->clear();
211   return false;
212 }
213