1 //===-- llvm/CodeGen/MachineModuleInfo.cpp ----------------------*- C++ -*-===// 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 #include "llvm/CodeGen/MachineModuleInfo.h" 11 12 #include "llvm/Constants.h" 13 #include "llvm/DerivedTypes.h" 14 #include "llvm/GlobalVariable.h" 15 #include "llvm/Intrinsics.h" 16 #include "llvm/Instructions.h" 17 #include "llvm/Module.h" 18 #include "llvm/Analysis/ValueTracking.h" 19 #include "llvm/CodeGen/MachineFunctionPass.h" 20 #include "llvm/CodeGen/MachineFunction.h" 21 #include "llvm/CodeGen/Passes.h" 22 #include "llvm/Target/TargetInstrInfo.h" 23 #include "llvm/Target/TargetMachine.h" 24 #include "llvm/Target/TargetOptions.h" 25 #include "llvm/MC/MCSymbol.h" 26 #include "llvm/Support/Dwarf.h" 27 #include "llvm/Support/ErrorHandling.h" 28 using namespace llvm; 29 using namespace llvm::dwarf; 30 31 // Handle the Pass registration stuff necessary to use TargetData's. 32 static RegisterPass<MachineModuleInfo> 33 X("machinemoduleinfo", "Machine Module Information"); 34 char MachineModuleInfo::ID = 0; 35 36 // Out of line virtual method. 37 MachineModuleInfoImpl::~MachineModuleInfoImpl() {} 38 39 //===----------------------------------------------------------------------===// 40 41 MachineModuleInfo::MachineModuleInfo(const MCAsmInfo &MAI) 42 : ImmutablePass(&ID), Context(MAI), 43 ObjFileMMI(0), 44 CurCallSite(0), CallsEHReturn(0), CallsUnwindInit(0), DbgInfoAvailable(false){ 45 // Always emit some info, by default "no personality" info. 46 Personalities.push_back(NULL); 47 } 48 49 MachineModuleInfo::MachineModuleInfo() 50 : ImmutablePass(&ID), Context(*(MCAsmInfo*)0) { 51 assert(0 && "This MachineModuleInfo constructor should never be called, MMI " 52 "should always be explicitly constructed by LLVMTargetMachine"); 53 abort(); 54 } 55 56 MachineModuleInfo::~MachineModuleInfo() { 57 delete ObjFileMMI; 58 } 59 60 /// doInitialization - Initialize the state for a new module. 61 /// 62 bool MachineModuleInfo::doInitialization() { 63 return false; 64 } 65 66 /// doFinalization - Tear down the state after completion of a module. 67 /// 68 bool MachineModuleInfo::doFinalization() { 69 return false; 70 } 71 72 /// EndFunction - Discard function meta information. 73 /// 74 void MachineModuleInfo::EndFunction() { 75 // Clean up frame info. 76 FrameMoves.clear(); 77 78 // Clean up exception info. 79 LandingPads.clear(); 80 CallSiteMap.clear(); 81 TypeInfos.clear(); 82 FilterIds.clear(); 83 FilterEnds.clear(); 84 CallsEHReturn = 0; 85 CallsUnwindInit = 0; 86 VariableDbgInfo.clear(); 87 } 88 89 /// AnalyzeModule - Scan the module for global debug information. 90 /// 91 void MachineModuleInfo::AnalyzeModule(Module &M) { 92 // Insert functions in the llvm.used array (but not llvm.compiler.used) into 93 // UsedFunctions. 94 GlobalVariable *GV = M.getGlobalVariable("llvm.used"); 95 if (!GV || !GV->hasInitializer()) return; 96 97 // Should be an array of 'i8*'. 98 ConstantArray *InitList = dyn_cast<ConstantArray>(GV->getInitializer()); 99 if (InitList == 0) return; 100 101 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) 102 if (Function *F = 103 dyn_cast<Function>(InitList->getOperand(i)->stripPointerCasts())) 104 UsedFunctions.insert(F); 105 } 106 107 //===-EH-------------------------------------------------------------------===// 108 109 /// getOrCreateLandingPadInfo - Find or create an LandingPadInfo for the 110 /// specified MachineBasicBlock. 111 LandingPadInfo &MachineModuleInfo::getOrCreateLandingPadInfo 112 (MachineBasicBlock *LandingPad) { 113 unsigned N = LandingPads.size(); 114 for (unsigned i = 0; i < N; ++i) { 115 LandingPadInfo &LP = LandingPads[i]; 116 if (LP.LandingPadBlock == LandingPad) 117 return LP; 118 } 119 120 LandingPads.push_back(LandingPadInfo(LandingPad)); 121 return LandingPads[N]; 122 } 123 124 /// addInvoke - Provide the begin and end labels of an invoke style call and 125 /// associate it with a try landing pad block. 126 void MachineModuleInfo::addInvoke(MachineBasicBlock *LandingPad, 127 MCSymbol *BeginLabel, MCSymbol *EndLabel) { 128 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad); 129 LP.BeginLabels.push_back(BeginLabel); 130 LP.EndLabels.push_back(EndLabel); 131 } 132 133 /// addLandingPad - Provide the label of a try LandingPad block. 134 /// 135 MCSymbol *MachineModuleInfo::addLandingPad(MachineBasicBlock *LandingPad) { 136 MCSymbol *LandingPadLabel = Context.CreateTempSymbol(); 137 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad); 138 LP.LandingPadLabel = LandingPadLabel; 139 return LandingPadLabel; 140 } 141 142 /// addPersonality - Provide the personality function for the exception 143 /// information. 144 void MachineModuleInfo::addPersonality(MachineBasicBlock *LandingPad, 145 Function *Personality) { 146 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad); 147 LP.Personality = Personality; 148 149 for (unsigned i = 0; i < Personalities.size(); ++i) 150 if (Personalities[i] == Personality) 151 return; 152 153 // If this is the first personality we're adding go 154 // ahead and add it at the beginning. 155 if (Personalities[0] == NULL) 156 Personalities[0] = Personality; 157 else 158 Personalities.push_back(Personality); 159 } 160 161 /// addCatchTypeInfo - Provide the catch typeinfo for a landing pad. 162 /// 163 void MachineModuleInfo::addCatchTypeInfo(MachineBasicBlock *LandingPad, 164 std::vector<GlobalVariable *> &TyInfo) { 165 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad); 166 for (unsigned N = TyInfo.size(); N; --N) 167 LP.TypeIds.push_back(getTypeIDFor(TyInfo[N - 1])); 168 } 169 170 /// addFilterTypeInfo - Provide the filter typeinfo for a landing pad. 171 /// 172 void MachineModuleInfo::addFilterTypeInfo(MachineBasicBlock *LandingPad, 173 std::vector<GlobalVariable *> &TyInfo) { 174 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad); 175 std::vector<unsigned> IdsInFilter(TyInfo.size()); 176 for (unsigned I = 0, E = TyInfo.size(); I != E; ++I) 177 IdsInFilter[I] = getTypeIDFor(TyInfo[I]); 178 LP.TypeIds.push_back(getFilterIDFor(IdsInFilter)); 179 } 180 181 /// addCleanup - Add a cleanup action for a landing pad. 182 /// 183 void MachineModuleInfo::addCleanup(MachineBasicBlock *LandingPad) { 184 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad); 185 LP.TypeIds.push_back(0); 186 } 187 188 /// TidyLandingPads - Remap landing pad labels and remove any deleted landing 189 /// pads. 190 void MachineModuleInfo::TidyLandingPads() { 191 for (unsigned i = 0; i != LandingPads.size(); ) { 192 LandingPadInfo &LandingPad = LandingPads[i]; 193 if (LandingPad.LandingPadLabel && !LandingPad.LandingPadLabel->isDefined()) 194 LandingPad.LandingPadLabel = 0; 195 196 // Special case: we *should* emit LPs with null LP MBB. This indicates 197 // "nounwind" case. 198 if (!LandingPad.LandingPadLabel && LandingPad.LandingPadBlock) { 199 LandingPads.erase(LandingPads.begin() + i); 200 continue; 201 } 202 203 for (unsigned j = 0, e = LandingPads[i].BeginLabels.size(); j != e; ++j) { 204 MCSymbol *BeginLabel = LandingPad.BeginLabels[j]; 205 MCSymbol *EndLabel = LandingPad.EndLabels[j]; 206 if (BeginLabel->isDefined() && EndLabel->isDefined()) continue; 207 208 LandingPad.BeginLabels.erase(LandingPad.BeginLabels.begin() + j); 209 LandingPad.EndLabels.erase(LandingPad.EndLabels.begin() + j); 210 --j, --e; 211 } 212 213 // Remove landing pads with no try-ranges. 214 if (LandingPads[i].BeginLabels.empty()) { 215 LandingPads.erase(LandingPads.begin() + i); 216 continue; 217 } 218 219 // If there is no landing pad, ensure that the list of typeids is empty. 220 // If the only typeid is a cleanup, this is the same as having no typeids. 221 if (!LandingPad.LandingPadBlock || 222 (LandingPad.TypeIds.size() == 1 && !LandingPad.TypeIds[0])) 223 LandingPad.TypeIds.clear(); 224 ++i; 225 } 226 } 227 228 /// getTypeIDFor - Return the type id for the specified typeinfo. This is 229 /// function wide. 230 unsigned MachineModuleInfo::getTypeIDFor(GlobalVariable *TI) { 231 for (unsigned i = 0, N = TypeInfos.size(); i != N; ++i) 232 if (TypeInfos[i] == TI) return i + 1; 233 234 TypeInfos.push_back(TI); 235 return TypeInfos.size(); 236 } 237 238 /// getFilterIDFor - Return the filter id for the specified typeinfos. This is 239 /// function wide. 240 int MachineModuleInfo::getFilterIDFor(std::vector<unsigned> &TyIds) { 241 // If the new filter coincides with the tail of an existing filter, then 242 // re-use the existing filter. Folding filters more than this requires 243 // re-ordering filters and/or their elements - probably not worth it. 244 for (std::vector<unsigned>::iterator I = FilterEnds.begin(), 245 E = FilterEnds.end(); I != E; ++I) { 246 unsigned i = *I, j = TyIds.size(); 247 248 while (i && j) 249 if (FilterIds[--i] != TyIds[--j]) 250 goto try_next; 251 252 if (!j) 253 // The new filter coincides with range [i, end) of the existing filter. 254 return -(1 + i); 255 256 try_next:; 257 } 258 259 // Add the new filter. 260 int FilterID = -(1 + FilterIds.size()); 261 FilterIds.reserve(FilterIds.size() + TyIds.size() + 1); 262 for (unsigned I = 0, N = TyIds.size(); I != N; ++I) 263 FilterIds.push_back(TyIds[I]); 264 FilterEnds.push_back(FilterIds.size()); 265 FilterIds.push_back(0); // terminator 266 return FilterID; 267 } 268 269 /// getPersonality - Return the personality function for the current function. 270 Function *MachineModuleInfo::getPersonality() const { 271 // FIXME: Until PR1414 will be fixed, we're using 1 personality function per 272 // function 273 return !LandingPads.empty() ? LandingPads[0].Personality : NULL; 274 } 275 276 /// getPersonalityIndex - Return unique index for current personality 277 /// function. NULL/first personality function should always get zero index. 278 unsigned MachineModuleInfo::getPersonalityIndex() const { 279 const Function* Personality = NULL; 280 281 // Scan landing pads. If there is at least one non-NULL personality - use it. 282 for (unsigned i = 0; i != LandingPads.size(); ++i) 283 if (LandingPads[i].Personality) { 284 Personality = LandingPads[i].Personality; 285 break; 286 } 287 288 for (unsigned i = 0; i < Personalities.size(); ++i) { 289 if (Personalities[i] == Personality) 290 return i; 291 } 292 293 // This will happen if the current personality function is 294 // in the zero index. 295 return 0; 296 } 297 298