1 //===-- LLVMTargetMachine.cpp - Implement the LLVMTargetMachine class -----===// 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 LLVMTargetMachine class. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "llvm/Target/TargetMachine.h" 15 #include "llvm/ADT/OwningPtr.h" 16 #include "llvm/Assembly/PrintModulePass.h" 17 #include "llvm/CodeGen/AsmPrinter.h" 18 #include "llvm/CodeGen/MachineFunctionAnalysis.h" 19 #include "llvm/CodeGen/MachineModuleInfo.h" 20 #include "llvm/CodeGen/Passes.h" 21 #include "llvm/MC/MCAsmInfo.h" 22 #include "llvm/MC/MCContext.h" 23 #include "llvm/MC/MCInstrInfo.h" 24 #include "llvm/MC/MCStreamer.h" 25 #include "llvm/MC/MCSubtargetInfo.h" 26 #include "llvm/PassManager.h" 27 #include "llvm/Support/CommandLine.h" 28 #include "llvm/Support/ErrorHandling.h" 29 #include "llvm/Support/FormattedStream.h" 30 #include "llvm/Support/TargetRegistry.h" 31 #include "llvm/Target/TargetInstrInfo.h" 32 #include "llvm/Target/TargetLowering.h" 33 #include "llvm/Target/TargetLoweringObjectFile.h" 34 #include "llvm/Target/TargetOptions.h" 35 #include "llvm/Target/TargetRegisterInfo.h" 36 #include "llvm/Target/TargetSubtargetInfo.h" 37 #include "llvm/Transforms/Scalar.h" 38 using namespace llvm; 39 40 // Enable or disable FastISel. Both options are needed, because 41 // FastISel is enabled by default with -fast, and we wish to be 42 // able to enable or disable fast-isel independently from -O0. 43 static cl::opt<cl::boolOrDefault> 44 EnableFastISelOption("fast-isel", cl::Hidden, 45 cl::desc("Enable the \"fast\" instruction selector")); 46 47 static cl::opt<bool> ShowMCEncoding("show-mc-encoding", cl::Hidden, 48 cl::desc("Show encoding in .s output")); 49 static cl::opt<bool> ShowMCInst("show-mc-inst", cl::Hidden, 50 cl::desc("Show instruction structure in .s output")); 51 52 static cl::opt<cl::boolOrDefault> 53 AsmVerbose("asm-verbose", cl::desc("Add comments to directives."), 54 cl::init(cl::BOU_UNSET)); 55 56 static bool getVerboseAsm() { 57 switch (AsmVerbose) { 58 case cl::BOU_UNSET: return TargetMachine::getAsmVerbosityDefault(); 59 case cl::BOU_TRUE: return true; 60 case cl::BOU_FALSE: return false; 61 } 62 llvm_unreachable("Invalid verbose asm state"); 63 } 64 65 void LLVMTargetMachine::initAsmInfo() { 66 AsmInfo = TheTarget.createMCAsmInfo(*getRegisterInfo(), TargetTriple); 67 // TargetSelect.h moved to a different directory between LLVM 2.9 and 3.0, 68 // and if the old one gets included then MCAsmInfo will be NULL and 69 // we'll crash later. 70 // Provide the user with a useful error message about what's wrong. 71 assert(AsmInfo && "MCAsmInfo not initialized. " 72 "Make sure you include the correct TargetSelect.h" 73 "and that InitializeAllTargetMCs() is being invoked!"); 74 } 75 76 LLVMTargetMachine::LLVMTargetMachine(const Target &T, StringRef Triple, 77 StringRef CPU, StringRef FS, 78 TargetOptions Options, 79 Reloc::Model RM, CodeModel::Model CM, 80 CodeGenOpt::Level OL) 81 : TargetMachine(T, Triple, CPU, FS, Options) { 82 CodeGenInfo = T.createMCCodeGenInfo(Triple, RM, CM, OL); 83 } 84 85 void LLVMTargetMachine::addAnalysisPasses(PassManagerBase &PM) { 86 PM.add(createBasicTargetTransformInfoPass(this)); 87 } 88 89 /// addPassesToX helper drives creation and initialization of TargetPassConfig. 90 static MCContext *addPassesToGenerateCode(LLVMTargetMachine *TM, 91 PassManagerBase &PM, 92 bool DisableVerify, 93 AnalysisID StartAfter, 94 AnalysisID StopAfter) { 95 // Targets may override createPassConfig to provide a target-specific sublass. 96 TargetPassConfig *PassConfig = TM->createPassConfig(PM); 97 PassConfig->setStartStopPasses(StartAfter, StopAfter); 98 99 // Set PassConfig options provided by TargetMachine. 100 PassConfig->setDisableVerify(DisableVerify); 101 102 PM.add(PassConfig); 103 104 PassConfig->addIRPasses(); 105 106 PassConfig->addCodeGenPrepare(); 107 108 PassConfig->addPassesToHandleExceptions(); 109 110 PassConfig->addISelPrepare(); 111 112 // Install a MachineModuleInfo class, which is an immutable pass that holds 113 // all the per-module stuff we're generating, including MCContext. 114 MachineModuleInfo *MMI = 115 new MachineModuleInfo(*TM->getMCAsmInfo(), *TM->getRegisterInfo(), 116 &TM->getTargetLowering()->getObjFileLowering()); 117 PM.add(MMI); 118 119 // Set up a MachineFunction for the rest of CodeGen to work on. 120 PM.add(new MachineFunctionAnalysis(*TM)); 121 122 // Enable FastISel with -fast, but allow that to be overridden. 123 if (EnableFastISelOption == cl::BOU_TRUE || 124 (TM->getOptLevel() == CodeGenOpt::None && 125 EnableFastISelOption != cl::BOU_FALSE)) 126 TM->setFastISel(true); 127 128 // Ask the target for an isel. 129 if (PassConfig->addInstSelector()) 130 return NULL; 131 132 PassConfig->addMachinePasses(); 133 134 PassConfig->setInitialized(); 135 136 return &MMI->getContext(); 137 } 138 139 bool LLVMTargetMachine::addPassesToEmitFile(PassManagerBase &PM, 140 formatted_raw_ostream &Out, 141 CodeGenFileType FileType, 142 bool DisableVerify, 143 AnalysisID StartAfter, 144 AnalysisID StopAfter) { 145 // Add common CodeGen passes. 146 MCContext *Context = addPassesToGenerateCode(this, PM, DisableVerify, 147 StartAfter, StopAfter); 148 if (!Context) 149 return true; 150 151 if (StopAfter) { 152 // FIXME: The intent is that this should eventually write out a YAML file, 153 // containing the LLVM IR, the machine-level IR (when stopping after a 154 // machine-level pass), and whatever other information is needed to 155 // deserialize the code and resume compilation. For now, just write the 156 // LLVM IR. 157 PM.add(createPrintModulePass(&Out)); 158 return false; 159 } 160 161 if (hasMCSaveTempLabels()) 162 Context->setAllowTemporaryLabels(false); 163 164 const MCAsmInfo &MAI = *getMCAsmInfo(); 165 const MCRegisterInfo &MRI = *getRegisterInfo(); 166 const MCInstrInfo &MII = *getInstrInfo(); 167 const MCSubtargetInfo &STI = getSubtarget<MCSubtargetInfo>(); 168 OwningPtr<MCStreamer> AsmStreamer; 169 170 switch (FileType) { 171 case CGFT_AssemblyFile: { 172 MCInstPrinter *InstPrinter = 173 getTarget().createMCInstPrinter(MAI.getAssemblerDialect(), MAI, 174 MII, MRI, STI); 175 176 // Create a code emitter if asked to show the encoding. 177 MCCodeEmitter *MCE = 0; 178 MCAsmBackend *MAB = 0; 179 if (ShowMCEncoding) { 180 MCE = getTarget().createMCCodeEmitter(MII, MRI, STI, *Context); 181 MAB = getTarget().createMCAsmBackend(getTargetTriple(), TargetCPU); 182 } 183 184 MCStreamer *S = getTarget().createAsmStreamer(*Context, Out, 185 getVerboseAsm(), 186 hasMCUseLoc(), 187 hasMCUseCFI(), 188 hasMCUseDwarfDirectory(), 189 InstPrinter, 190 MCE, MAB, 191 ShowMCInst); 192 AsmStreamer.reset(S); 193 break; 194 } 195 case CGFT_ObjectFile: { 196 // Create the code emitter for the target if it exists. If not, .o file 197 // emission fails. 198 MCCodeEmitter *MCE = getTarget().createMCCodeEmitter(MII, MRI, STI, 199 *Context); 200 MCAsmBackend *MAB = getTarget().createMCAsmBackend(getTargetTriple(), 201 TargetCPU); 202 if (MCE == 0 || MAB == 0) 203 return true; 204 205 AsmStreamer.reset(getTarget().createMCObjectStreamer(getTargetTriple(), 206 *Context, *MAB, Out, 207 MCE, hasMCRelaxAll(), 208 hasMCNoExecStack())); 209 AsmStreamer.get()->setAutoInitSections(true); 210 break; 211 } 212 case CGFT_Null: 213 // The Null output is intended for use for performance analysis and testing, 214 // not real users. 215 AsmStreamer.reset(createNullStreamer(*Context)); 216 break; 217 } 218 219 // Create the AsmPrinter, which takes ownership of AsmStreamer if successful. 220 FunctionPass *Printer = getTarget().createAsmPrinter(*this, *AsmStreamer); 221 if (Printer == 0) 222 return true; 223 224 // If successful, createAsmPrinter took ownership of AsmStreamer. 225 AsmStreamer.take(); 226 227 PM.add(Printer); 228 229 return false; 230 } 231 232 /// addPassesToEmitMachineCode - Add passes to the specified pass manager to 233 /// get machine code emitted. This uses a JITCodeEmitter object to handle 234 /// actually outputting the machine code and resolving things like the address 235 /// of functions. This method should returns true if machine code emission is 236 /// not supported. 237 /// 238 bool LLVMTargetMachine::addPassesToEmitMachineCode(PassManagerBase &PM, 239 JITCodeEmitter &JCE, 240 bool DisableVerify) { 241 // Add common CodeGen passes. 242 MCContext *Context = addPassesToGenerateCode(this, PM, DisableVerify, 0, 0); 243 if (!Context) 244 return true; 245 246 addCodeEmitter(PM, JCE); 247 248 return false; // success! 249 } 250 251 /// addPassesToEmitMC - Add passes to the specified pass manager to get 252 /// machine code emitted with the MCJIT. This method returns true if machine 253 /// code is not supported. It fills the MCContext Ctx pointer which can be 254 /// used to build custom MCStreamer. 255 /// 256 bool LLVMTargetMachine::addPassesToEmitMC(PassManagerBase &PM, 257 MCContext *&Ctx, 258 raw_ostream &Out, 259 bool DisableVerify) { 260 // Add common CodeGen passes. 261 Ctx = addPassesToGenerateCode(this, PM, DisableVerify, 0, 0); 262 if (!Ctx) 263 return true; 264 265 if (hasMCSaveTempLabels()) 266 Ctx->setAllowTemporaryLabels(false); 267 268 // Create the code emitter for the target if it exists. If not, .o file 269 // emission fails. 270 const MCRegisterInfo &MRI = *getRegisterInfo(); 271 const MCSubtargetInfo &STI = getSubtarget<MCSubtargetInfo>(); 272 MCCodeEmitter *MCE = getTarget().createMCCodeEmitter(*getInstrInfo(), MRI, 273 STI, *Ctx); 274 MCAsmBackend *MAB = getTarget().createMCAsmBackend(getTargetTriple(), TargetCPU); 275 if (MCE == 0 || MAB == 0) 276 return true; 277 278 OwningPtr<MCStreamer> AsmStreamer; 279 AsmStreamer.reset(getTarget().createMCObjectStreamer(getTargetTriple(), *Ctx, 280 *MAB, Out, MCE, 281 hasMCRelaxAll(), 282 hasMCNoExecStack())); 283 AsmStreamer.get()->InitSections(); 284 285 // Create the AsmPrinter, which takes ownership of AsmStreamer if successful. 286 FunctionPass *Printer = getTarget().createAsmPrinter(*this, *AsmStreamer); 287 if (Printer == 0) 288 return true; 289 290 // If successful, createAsmPrinter took ownership of AsmStreamer. 291 AsmStreamer.take(); 292 293 PM.add(Printer); 294 295 return false; // success! 296 } 297