TargetMachine.h revision 48814681d72242e0179d7100f263952fdf4f51d6
1//===-- llvm/Target/TargetMachine.h - Target Information --------*- 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// This file defines the TargetMachine and LLVMTargetMachine classes. 11// 12//===----------------------------------------------------------------------===// 13 14#ifndef LLVM_TARGET_TARGETMACHINE_H 15#define LLVM_TARGET_TARGETMACHINE_H 16 17#include "llvm/Target/TargetInstrItineraries.h" 18#include <cassert> 19#include <string> 20 21namespace llvm { 22 23class Target; 24class MCAsmInfo; 25class TargetData; 26class TargetSubtarget; 27class TargetInstrInfo; 28class TargetIntrinsicInfo; 29class TargetJITInfo; 30class TargetLowering; 31class TargetFrameInfo; 32class MachineCodeEmitter; 33class JITCodeEmitter; 34class ObjectCodeEmitter; 35class TargetRegisterInfo; 36class PassManagerBase; 37class PassManager; 38class Pass; 39class TargetMachOWriterInfo; 40class TargetELFWriterInfo; 41class formatted_raw_ostream; 42 43// Relocation model types. 44namespace Reloc { 45 enum Model { 46 Default, 47 Static, 48 PIC_, // Cannot be named PIC due to collision with -DPIC 49 DynamicNoPIC 50 }; 51} 52 53// Code model types. 54namespace CodeModel { 55 enum Model { 56 Default, 57 Small, 58 Kernel, 59 Medium, 60 Large 61 }; 62} 63 64namespace FileModel { 65 enum Model { 66 Error, 67 None, 68 AsmFile, 69 MachOFile, 70 ElfFile 71 }; 72} 73 74// Code generation optimization level. 75namespace CodeGenOpt { 76 enum Level { 77 None, // -O0 78 Less, // -O1 79 Default, // -O2, -Os 80 Aggressive // -O3 81 }; 82} 83 84// Specify if we should encode the LSDA pointer in the FDE as 4- or 8-bytes. 85namespace DwarfLSDAEncoding { 86 enum Encoding { 87 Default, 88 FourByte, 89 EightByte 90 }; 91} 92 93//===----------------------------------------------------------------------===// 94/// 95/// TargetMachine - Primary interface to the complete machine description for 96/// the target machine. All target-specific information should be accessible 97/// through this interface. 98/// 99class TargetMachine { 100 TargetMachine(const TargetMachine &); // DO NOT IMPLEMENT 101 void operator=(const TargetMachine &); // DO NOT IMPLEMENT 102protected: // Can only create subclasses. 103 TargetMachine(const Target &); 104 105 /// getSubtargetImpl - virtual method implemented by subclasses that returns 106 /// a reference to that target's TargetSubtarget-derived member variable. 107 virtual const TargetSubtarget *getSubtargetImpl() const { return 0; } 108 109 /// TheTarget - The Target that this machine was created for. 110 const Target &TheTarget; 111 112 /// AsmInfo - Contains target specific asm information. 113 /// 114 const MCAsmInfo *AsmInfo; 115 116public: 117 virtual ~TargetMachine(); 118 119 const Target &getTarget() const { return TheTarget; } 120 121 // Interfaces to the major aspects of target machine information: 122 // -- Instruction opcode and operand information 123 // -- Pipelines and scheduling information 124 // -- Stack frame information 125 // -- Selection DAG lowering information 126 // 127 virtual const TargetInstrInfo *getInstrInfo() const { return 0; } 128 virtual const TargetFrameInfo *getFrameInfo() const { return 0; } 129 virtual TargetLowering *getTargetLowering() const { return 0; } 130 virtual const TargetData *getTargetData() const { return 0; } 131 132 /// getMCAsmInfo - Return target specific asm information. 133 /// 134 const MCAsmInfo *getMCAsmInfo() const { return AsmInfo; } 135 136 /// getSubtarget - This method returns a pointer to the specified type of 137 /// TargetSubtarget. In debug builds, it verifies that the object being 138 /// returned is of the correct type. 139 template<typename STC> const STC &getSubtarget() const { 140 const TargetSubtarget *TST = getSubtargetImpl(); 141 assert(TST && dynamic_cast<const STC*>(TST) && 142 "Not the right kind of subtarget!"); 143 return *static_cast<const STC*>(TST); 144 } 145 146 /// getRegisterInfo - If register information is available, return it. If 147 /// not, return null. This is kept separate from RegInfo until RegInfo has 148 /// details of graph coloring register allocation removed from it. 149 /// 150 virtual const TargetRegisterInfo *getRegisterInfo() const { return 0; } 151 152 /// getIntrinsicInfo - If intrinsic information is available, return it. If 153 /// not, return null. 154 /// 155 virtual const TargetIntrinsicInfo *getIntrinsicInfo() const { return 0; } 156 157 /// getJITInfo - If this target supports a JIT, return information for it, 158 /// otherwise return null. 159 /// 160 virtual TargetJITInfo *getJITInfo() { return 0; } 161 162 /// getInstrItineraryData - Returns instruction itinerary data for the target 163 /// or specific subtarget. 164 /// 165 virtual const InstrItineraryData getInstrItineraryData() const { 166 return InstrItineraryData(); 167 } 168 169 /// getMachOWriterInfo - If this target supports a Mach-O writer, return 170 /// information for it, otherwise return null. 171 /// 172 virtual const TargetMachOWriterInfo *getMachOWriterInfo() const { return 0; } 173 174 /// getELFWriterInfo - If this target supports an ELF writer, return 175 /// information for it, otherwise return null. 176 /// 177 virtual const TargetELFWriterInfo *getELFWriterInfo() const { return 0; } 178 179 /// getRelocationModel - Returns the code generation relocation model. The 180 /// choices are static, PIC, and dynamic-no-pic, and target default. 181 static Reloc::Model getRelocationModel(); 182 183 /// setRelocationModel - Sets the code generation relocation model. 184 /// 185 static void setRelocationModel(Reloc::Model Model); 186 187 /// getCodeModel - Returns the code model. The choices are small, kernel, 188 /// medium, large, and target default. 189 static CodeModel::Model getCodeModel(); 190 191 /// setCodeModel - Sets the code model. 192 /// 193 static void setCodeModel(CodeModel::Model Model); 194 195 /// getAsmVerbosityDefault - Returns the default value of asm verbosity. 196 /// 197 static bool getAsmVerbosityDefault(); 198 199 /// setAsmVerbosityDefault - Set the default value of asm verbosity. Default 200 /// is false. 201 static void setAsmVerbosityDefault(bool); 202 203 /// getLSDAEncoding - Returns the LSDA pointer encoding. The choices are 204 /// 4-byte, 8-byte, and target default. The CIE is hard-coded to indicate that 205 /// the LSDA pointer in the FDE section is an "sdata4", and should be encoded 206 /// as a 4-byte pointer by default. However, some systems may require a 207 /// different size due to bugs or other conditions. We will default to a 208 /// 4-byte encoding unless the system tells us otherwise. 209 /// 210 /// FIXME: This call-back isn't good! We should be using the correct encoding 211 /// regardless of the system. However, there are some systems which have bugs 212 /// that prevent this from occuring. 213 virtual DwarfLSDAEncoding::Encoding getLSDAEncoding() const { 214 return DwarfLSDAEncoding::Default; 215 } 216 217 /// CodeGenFileType - These enums are meant to be passed into 218 /// addPassesToEmitFile to indicate what type of file to emit. 219 enum CodeGenFileType { 220 AssemblyFile, ObjectFile, DynamicLibrary 221 }; 222 223 /// getEnableTailMergeDefault - the default setting for -enable-tail-merge 224 /// on this target. User flag overrides. 225 virtual bool getEnableTailMergeDefault() const { return true; } 226 227 /// addPassesToEmitFile - Add passes to the specified pass manager to get the 228 /// specified file emitted. Typically this will involve several steps of code 229 /// generation. 230 /// This method should return FileModel::Error if emission of this file type 231 /// is not supported. 232 /// 233 virtual FileModel::Model addPassesToEmitFile(PassManagerBase &, 234 formatted_raw_ostream &, 235 CodeGenFileType, 236 CodeGenOpt::Level) { 237 return FileModel::None; 238 } 239 240 /// addPassesToEmitFileFinish - If the passes to emit the specified file had 241 /// to be split up (e.g., to add an object writer pass), this method can be 242 /// used to finish up adding passes to emit the file, if necessary. 243 /// 244 virtual bool addPassesToEmitFileFinish(PassManagerBase &, 245 MachineCodeEmitter *, 246 CodeGenOpt::Level) { 247 return true; 248 } 249 250 /// addPassesToEmitFileFinish - If the passes to emit the specified file had 251 /// to be split up (e.g., to add an object writer pass), this method can be 252 /// used to finish up adding passes to emit the file, if necessary. 253 /// 254 virtual bool addPassesToEmitFileFinish(PassManagerBase &, 255 JITCodeEmitter *, 256 CodeGenOpt::Level) { 257 return true; 258 } 259 260 /// addPassesToEmitFileFinish - If the passes to emit the specified file had 261 /// to be split up (e.g., to add an object writer pass), this method can be 262 /// used to finish up adding passes to emit the file, if necessary. 263 /// 264 virtual bool addPassesToEmitFileFinish(PassManagerBase &, 265 ObjectCodeEmitter *, 266 CodeGenOpt::Level) { 267 return true; 268 } 269 270 /// addPassesToEmitMachineCode - Add passes to the specified pass manager to 271 /// get machine code emitted. This uses a MachineCodeEmitter object to handle 272 /// actually outputting the machine code and resolving things like the address 273 /// of functions. This method returns true if machine code emission is 274 /// not supported. 275 /// 276 virtual bool addPassesToEmitMachineCode(PassManagerBase &, 277 MachineCodeEmitter &, 278 CodeGenOpt::Level) { 279 return true; 280 } 281 282 /// addPassesToEmitMachineCode - Add passes to the specified pass manager to 283 /// get machine code emitted. This uses a MachineCodeEmitter object to handle 284 /// actually outputting the machine code and resolving things like the address 285 /// of functions. This method returns true if machine code emission is 286 /// not supported. 287 /// 288 virtual bool addPassesToEmitMachineCode(PassManagerBase &, 289 JITCodeEmitter &, 290 CodeGenOpt::Level) { 291 return true; 292 } 293 294 /// addPassesToEmitWholeFile - This method can be implemented by targets that 295 /// require having the entire module at once. This is not recommended, do not 296 /// use this. 297 virtual bool WantsWholeFile() const { return false; } 298 virtual bool addPassesToEmitWholeFile(PassManager &, formatted_raw_ostream &, 299 CodeGenFileType, 300 CodeGenOpt::Level) { 301 return true; 302 } 303}; 304 305/// LLVMTargetMachine - This class describes a target machine that is 306/// implemented with the LLVM target-independent code generator. 307/// 308class LLVMTargetMachine : public TargetMachine { 309protected: // Can only create subclasses. 310 LLVMTargetMachine(const Target &T, const std::string &TargetTriple); 311 312 /// addCommonCodeGenPasses - Add standard LLVM codegen passes used for 313 /// both emitting to assembly files or machine code output. 314 /// 315 bool addCommonCodeGenPasses(PassManagerBase &, CodeGenOpt::Level); 316 317private: 318 // These routines are used by addPassesToEmitFileFinish and 319 // addPassesToEmitMachineCode to set the CodeModel if it's still marked 320 // as default. 321 virtual void setCodeModelForJIT(); 322 virtual void setCodeModelForStatic(); 323 324public: 325 326 /// addPassesToEmitFile - Add passes to the specified pass manager to get the 327 /// specified file emitted. Typically this will involve several steps of code 328 /// generation. If OptLevel is None, the code generator should emit code as fast 329 /// as possible, though the generated code may be less efficient. This method 330 /// should return FileModel::Error if emission of this file type is not 331 /// supported. 332 /// 333 /// The default implementation of this method adds components from the 334 /// LLVM retargetable code generator, invoking the methods below to get 335 /// target-specific passes in standard locations. 336 /// 337 virtual FileModel::Model addPassesToEmitFile(PassManagerBase &PM, 338 formatted_raw_ostream &Out, 339 CodeGenFileType FileType, 340 CodeGenOpt::Level); 341 342 /// addPassesToEmitFileFinish - If the passes to emit the specified file had 343 /// to be split up (e.g., to add an object writer pass), this method can be 344 /// used to finish up adding passes to emit the file, if necessary. 345 /// 346 virtual bool addPassesToEmitFileFinish(PassManagerBase &PM, 347 MachineCodeEmitter *MCE, 348 CodeGenOpt::Level); 349 350 /// addPassesToEmitFileFinish - If the passes to emit the specified file had 351 /// to be split up (e.g., to add an object writer pass), this method can be 352 /// used to finish up adding passes to emit the file, if necessary. 353 /// 354 virtual bool addPassesToEmitFileFinish(PassManagerBase &PM, 355 JITCodeEmitter *JCE, 356 CodeGenOpt::Level); 357 358 /// addPassesToEmitFileFinish - If the passes to emit the specified file had 359 /// to be split up (e.g., to add an object writer pass), this method can be 360 /// used to finish up adding passes to emit the file, if necessary. 361 /// 362 virtual bool addPassesToEmitFileFinish(PassManagerBase &PM, 363 ObjectCodeEmitter *OCE, 364 CodeGenOpt::Level); 365 366 /// addPassesToEmitMachineCode - Add passes to the specified pass manager to 367 /// get machine code emitted. This uses a MachineCodeEmitter object to handle 368 /// actually outputting the machine code and resolving things like the address 369 /// of functions. This method returns true if machine code emission is 370 /// not supported. 371 /// 372 virtual bool addPassesToEmitMachineCode(PassManagerBase &PM, 373 MachineCodeEmitter &MCE, 374 CodeGenOpt::Level); 375 376 /// addPassesToEmitMachineCode - Add passes to the specified pass manager to 377 /// get machine code emitted. This uses a MachineCodeEmitter object to handle 378 /// actually outputting the machine code and resolving things like the address 379 /// of functions. This method returns true if machine code emission is 380 /// not supported. 381 /// 382 virtual bool addPassesToEmitMachineCode(PassManagerBase &PM, 383 JITCodeEmitter &MCE, 384 CodeGenOpt::Level); 385 386 /// Target-Independent Code Generator Pass Configuration Options. 387 388 /// addInstSelector - This method should add any "last minute" LLVM->LLVM 389 /// passes, then install an instruction selector pass, which converts from 390 /// LLVM code to machine instructions. 391 virtual bool addInstSelector(PassManagerBase &, CodeGenOpt::Level) { 392 return true; 393 } 394 395 /// addPreRegAlloc - This method may be implemented by targets that want to 396 /// run passes immediately before register allocation. This should return 397 /// true if -print-machineinstrs should print after these passes. 398 virtual bool addPreRegAlloc(PassManagerBase &, CodeGenOpt::Level) { 399 return false; 400 } 401 402 /// addPostRegAlloc - This method may be implemented by targets that want 403 /// to run passes after register allocation but before prolog-epilog 404 /// insertion. This should return true if -print-machineinstrs should print 405 /// after these passes. 406 virtual bool addPostRegAlloc(PassManagerBase &, CodeGenOpt::Level) { 407 return false; 408 } 409 410 /// addPreSched2 - This method may be implemented by targets that want to 411 /// run passes after prolog-epilog insertion and before the second instruction 412 /// scheduling pass. This should return true if -print-machineinstrs should 413 /// print after these passes. 414 virtual bool addPreSched2(PassManagerBase &, CodeGenOpt::Level) { 415 return false; 416 } 417 418 /// addPreEmitPass - This pass may be implemented by targets that want to run 419 /// passes immediately before machine code is emitted. This should return 420 /// true if -print-machineinstrs should print out the code after the passes. 421 virtual bool addPreEmitPass(PassManagerBase &, CodeGenOpt::Level) { 422 return false; 423 } 424 425 426 /// addCodeEmitter - This pass should be overridden by the target to add a 427 /// code emitter, if supported. If this is not supported, 'true' should be 428 /// returned. 429 virtual bool addCodeEmitter(PassManagerBase &, CodeGenOpt::Level, 430 MachineCodeEmitter &) { 431 return true; 432 } 433 434 /// addCodeEmitter - This pass should be overridden by the target to add a 435 /// code emitter, if supported. If this is not supported, 'true' should be 436 /// returned. 437 virtual bool addCodeEmitter(PassManagerBase &, CodeGenOpt::Level, 438 JITCodeEmitter &) { 439 return true; 440 } 441 442 /// addSimpleCodeEmitter - This pass should be overridden by the target to add 443 /// a code emitter (without setting flags), if supported. If this is not 444 /// supported, 'true' should be returned. 445 virtual bool addSimpleCodeEmitter(PassManagerBase &, CodeGenOpt::Level, 446 MachineCodeEmitter &) { 447 return true; 448 } 449 450 /// addSimpleCodeEmitter - This pass should be overridden by the target to add 451 /// a code emitter (without setting flags), if supported. If this is not 452 /// supported, 'true' should be returned. 453 virtual bool addSimpleCodeEmitter(PassManagerBase &, CodeGenOpt::Level, 454 JITCodeEmitter &) { 455 return true; 456 } 457 458 /// addSimpleCodeEmitter - This pass should be overridden by the target to add 459 /// a code emitter (without setting flags), if supported. If this is not 460 /// supported, 'true' should be returned. 461 virtual bool addSimpleCodeEmitter(PassManagerBase &, CodeGenOpt::Level, 462 ObjectCodeEmitter &) { 463 return true; 464 } 465 466 /// getEnableTailMergeDefault - the default setting for -enable-tail-merge 467 /// on this target. User flag overrides. 468 virtual bool getEnableTailMergeDefault() const { return true; } 469 470 /// addAssemblyEmitter - Helper function which creates a target specific 471 /// assembly printer, if available. 472 /// 473 /// \return Returns 'false' on success. 474 bool addAssemblyEmitter(PassManagerBase &, CodeGenOpt::Level, 475 bool /* VerboseAsmDefault */, 476 formatted_raw_ostream &); 477 478 /// addObjectFileEmitter - Helper function which creates a target specific 479 /// object files emitter, if available. This interface is temporary, for 480 /// bringing up MCAssembler-based object file emitters. 481 /// 482 /// \return Returns 'false' on success. 483 bool addObjectFileEmitter(PassManagerBase &, CodeGenOpt::Level, 484 formatted_raw_ostream &); 485}; 486 487} // End llvm namespace 488 489#endif 490