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