MCExpr.h revision 349c2787cf9e174c8aa955bf8e3b09a405b2aece
1//===- MCExpr.h - Assembly Level Expressions --------------------*- 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#ifndef LLVM_MC_MCEXPR_H 11#define LLVM_MC_MCEXPR_H 12 13#include "llvm/ADT/DenseMap.h" 14#include "llvm/Support/Casting.h" 15#include "llvm/Support/DataTypes.h" 16 17namespace llvm { 18class MCAsmLayout; 19class MCAssembler; 20class MCContext; 21class MCSection; 22class MCSectionData; 23class MCSymbol; 24class MCValue; 25class raw_ostream; 26class StringRef; 27typedef DenseMap<const MCSectionData*, uint64_t> SectionAddrMap; 28 29/// MCExpr - Base class for the full range of assembler expressions which are 30/// needed for parsing. 31class MCExpr { 32public: 33 enum ExprKind { 34 Binary, ///< Binary expressions. 35 Constant, ///< Constant expressions. 36 SymbolRef, ///< References to labels and assigned expressions. 37 Unary, ///< Unary expressions. 38 Target ///< Target specific expression. 39 }; 40 41private: 42 ExprKind Kind; 43 44 MCExpr(const MCExpr&) LLVM_DELETED_FUNCTION; 45 void operator=(const MCExpr&) LLVM_DELETED_FUNCTION; 46 47 bool EvaluateAsAbsolute(int64_t &Res, const MCAssembler *Asm, 48 const MCAsmLayout *Layout, 49 const SectionAddrMap *Addrs) const; 50protected: 51 explicit MCExpr(ExprKind _Kind) : Kind(_Kind) {} 52 53 bool EvaluateAsRelocatableImpl(MCValue &Res, const MCAssembler *Asm, 54 const MCAsmLayout *Layout, 55 const SectionAddrMap *Addrs, 56 bool InSet) const; 57public: 58 /// @name Accessors 59 /// @{ 60 61 ExprKind getKind() const { return Kind; } 62 63 /// @} 64 /// @name Utility Methods 65 /// @{ 66 67 void print(raw_ostream &OS) const; 68 void dump() const; 69 70 /// @} 71 /// @name Expression Evaluation 72 /// @{ 73 74 /// EvaluateAsAbsolute - Try to evaluate the expression to an absolute value. 75 /// 76 /// @param Res - The absolute value, if evaluation succeeds. 77 /// @param Layout - The assembler layout object to use for evaluating symbol 78 /// values. If not given, then only non-symbolic expressions will be 79 /// evaluated. 80 /// @result - True on success. 81 bool EvaluateAsAbsolute(int64_t &Res, const MCAsmLayout &Layout, 82 const SectionAddrMap &Addrs) const; 83 bool EvaluateAsAbsolute(int64_t &Res) const; 84 bool EvaluateAsAbsolute(int64_t &Res, const MCAssembler &Asm) const; 85 bool EvaluateAsAbsolute(int64_t &Res, const MCAsmLayout &Layout) const; 86 87 /// EvaluateAsRelocatable - Try to evaluate the expression to a relocatable 88 /// value, i.e. an expression of the fixed form (a - b + constant). 89 /// 90 /// @param Res - The relocatable value, if evaluation succeeds. 91 /// @param Layout - The assembler layout object to use for evaluating values. 92 /// @result - True on success. 93 bool EvaluateAsRelocatable(MCValue &Res, const MCAsmLayout &Layout) const; 94 95 /// FindAssociatedSection - Find the "associated section" for this expression, 96 /// which is currently defined as the absolute section for constants, or 97 /// otherwise the section associated with the first defined symbol in the 98 /// expression. 99 const MCSection *FindAssociatedSection() const; 100 101 /// @} 102}; 103 104inline raw_ostream &operator<<(raw_ostream &OS, const MCExpr &E) { 105 E.print(OS); 106 return OS; 107} 108 109//// MCConstantExpr - Represent a constant integer expression. 110class MCConstantExpr : public MCExpr { 111 int64_t Value; 112 113 explicit MCConstantExpr(int64_t _Value) 114 : MCExpr(MCExpr::Constant), Value(_Value) {} 115 116public: 117 /// @name Construction 118 /// @{ 119 120 static const MCConstantExpr *Create(int64_t Value, MCContext &Ctx); 121 122 /// @} 123 /// @name Accessors 124 /// @{ 125 126 int64_t getValue() const { return Value; } 127 128 /// @} 129 130 static bool classof(const MCExpr *E) { 131 return E->getKind() == MCExpr::Constant; 132 } 133}; 134 135/// MCSymbolRefExpr - Represent a reference to a symbol from inside an 136/// expression. 137/// 138/// A symbol reference in an expression may be a use of a label, a use of an 139/// assembler variable (defined constant), or constitute an implicit definition 140/// of the symbol as external. 141class MCSymbolRefExpr : public MCExpr { 142public: 143 enum VariantKind { 144 VK_None, 145 VK_Invalid, 146 147 VK_GOT, 148 VK_GOTOFF, 149 VK_GOTPCREL, 150 VK_GOTTPOFF, 151 VK_INDNTPOFF, 152 VK_NTPOFF, 153 VK_GOTNTPOFF, 154 VK_PLT, 155 VK_TLSGD, 156 VK_TLSLD, 157 VK_TLSLDM, 158 VK_TPOFF, 159 VK_DTPOFF, 160 VK_TLVP, // Mach-O thread local variable relocation 161 VK_SECREL, 162 // FIXME: We'd really like to use the generic Kinds listed above for these. 163 VK_ARM_NONE, 164 VK_ARM_PLT, // ARM-style PLT references. i.e., (PLT) instead of @PLT 165 VK_ARM_TLSGD, // ditto for TLSGD, GOT, GOTOFF, TPOFF and GOTTPOFF 166 VK_ARM_GOT, 167 VK_ARM_GOTOFF, 168 VK_ARM_TPOFF, 169 VK_ARM_GOTTPOFF, 170 VK_ARM_TARGET1, 171 VK_ARM_TARGET2, 172 VK_ARM_PREL31, 173 174 VK_PPC_TOC, // TOC base 175 VK_PPC_TOC_ENTRY, // TOC entry 176 VK_PPC_DARWIN_HA16, // ha16(symbol) 177 VK_PPC_DARWIN_LO16, // lo16(symbol) 178 VK_PPC_GAS_HA16, // symbol@ha 179 VK_PPC_GAS_LO16, // symbol@l 180 VK_PPC_TPREL16_HA, // symbol@tprel@ha 181 VK_PPC_TPREL16_LO, // symbol@tprel@l 182 VK_PPC_DTPREL16_HA, // symbol@dtprel@ha 183 VK_PPC_DTPREL16_LO, // symbol@dtprel@l 184 VK_PPC_TOC16_HA, // symbol@toc@ha 185 VK_PPC_TOC16_LO, // symbol@toc@l 186 VK_PPC_GOT_TPREL16_DS, // symbol@got@tprel 187 VK_PPC_TLS, // symbol@tls 188 VK_PPC_GOT_TLSGD16_HA, // symbol@got@tlsgd@ha 189 VK_PPC_GOT_TLSGD16_LO, // symbol@got@tlsgd@l 190 VK_PPC_TLSGD, // symbol@tlsgd 191 VK_PPC_GOT_TLSLD16_HA, // symbol@got@tlsld@ha 192 VK_PPC_GOT_TLSLD16_LO, // symbol@got@tlsld@l 193 VK_PPC_TLSLD, // symbol@tlsld 194 195 VK_Mips_GPREL, 196 VK_Mips_GOT_CALL, 197 VK_Mips_GOT16, 198 VK_Mips_GOT, 199 VK_Mips_ABS_HI, 200 VK_Mips_ABS_LO, 201 VK_Mips_TLSGD, 202 VK_Mips_TLSLDM, 203 VK_Mips_DTPREL_HI, 204 VK_Mips_DTPREL_LO, 205 VK_Mips_GOTTPREL, 206 VK_Mips_TPREL_HI, 207 VK_Mips_TPREL_LO, 208 VK_Mips_GPOFF_HI, 209 VK_Mips_GPOFF_LO, 210 VK_Mips_GOT_DISP, 211 VK_Mips_GOT_PAGE, 212 VK_Mips_GOT_OFST, 213 VK_Mips_HIGHER, 214 VK_Mips_HIGHEST, 215 VK_Mips_GOT_HI16, 216 VK_Mips_GOT_LO16, 217 VK_Mips_CALL_HI16, 218 VK_Mips_CALL_LO16 219 }; 220 221private: 222 /// The symbol being referenced. 223 const MCSymbol *Symbol; 224 225 /// The symbol reference modifier. 226 const VariantKind Kind; 227 228 explicit MCSymbolRefExpr(const MCSymbol *_Symbol, VariantKind _Kind) 229 : MCExpr(MCExpr::SymbolRef), Symbol(_Symbol), Kind(_Kind) { 230 assert(Symbol); 231 } 232 233public: 234 /// @name Construction 235 /// @{ 236 237 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, MCContext &Ctx) { 238 return MCSymbolRefExpr::Create(Symbol, VK_None, Ctx); 239 } 240 241 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, VariantKind Kind, 242 MCContext &Ctx); 243 static const MCSymbolRefExpr *Create(StringRef Name, VariantKind Kind, 244 MCContext &Ctx); 245 246 /// @} 247 /// @name Accessors 248 /// @{ 249 250 const MCSymbol &getSymbol() const { return *Symbol; } 251 252 VariantKind getKind() const { return Kind; } 253 254 /// @} 255 /// @name Static Utility Functions 256 /// @{ 257 258 static StringRef getVariantKindName(VariantKind Kind); 259 260 static VariantKind getVariantKindForName(StringRef Name); 261 262 /// @} 263 264 static bool classof(const MCExpr *E) { 265 return E->getKind() == MCExpr::SymbolRef; 266 } 267}; 268 269/// MCUnaryExpr - Unary assembler expressions. 270class MCUnaryExpr : public MCExpr { 271public: 272 enum Opcode { 273 LNot, ///< Logical negation. 274 Minus, ///< Unary minus. 275 Not, ///< Bitwise negation. 276 Plus ///< Unary plus. 277 }; 278 279private: 280 Opcode Op; 281 const MCExpr *Expr; 282 283 MCUnaryExpr(Opcode _Op, const MCExpr *_Expr) 284 : MCExpr(MCExpr::Unary), Op(_Op), Expr(_Expr) {} 285 286public: 287 /// @name Construction 288 /// @{ 289 290 static const MCUnaryExpr *Create(Opcode Op, const MCExpr *Expr, 291 MCContext &Ctx); 292 static const MCUnaryExpr *CreateLNot(const MCExpr *Expr, MCContext &Ctx) { 293 return Create(LNot, Expr, Ctx); 294 } 295 static const MCUnaryExpr *CreateMinus(const MCExpr *Expr, MCContext &Ctx) { 296 return Create(Minus, Expr, Ctx); 297 } 298 static const MCUnaryExpr *CreateNot(const MCExpr *Expr, MCContext &Ctx) { 299 return Create(Not, Expr, Ctx); 300 } 301 static const MCUnaryExpr *CreatePlus(const MCExpr *Expr, MCContext &Ctx) { 302 return Create(Plus, Expr, Ctx); 303 } 304 305 /// @} 306 /// @name Accessors 307 /// @{ 308 309 /// getOpcode - Get the kind of this unary expression. 310 Opcode getOpcode() const { return Op; } 311 312 /// getSubExpr - Get the child of this unary expression. 313 const MCExpr *getSubExpr() const { return Expr; } 314 315 /// @} 316 317 static bool classof(const MCExpr *E) { 318 return E->getKind() == MCExpr::Unary; 319 } 320}; 321 322/// MCBinaryExpr - Binary assembler expressions. 323class MCBinaryExpr : public MCExpr { 324public: 325 enum Opcode { 326 Add, ///< Addition. 327 And, ///< Bitwise and. 328 Div, ///< Signed division. 329 EQ, ///< Equality comparison. 330 GT, ///< Signed greater than comparison (result is either 0 or some 331 ///< target-specific non-zero value) 332 GTE, ///< Signed greater than or equal comparison (result is either 0 or 333 ///< some target-specific non-zero value). 334 LAnd, ///< Logical and. 335 LOr, ///< Logical or. 336 LT, ///< Signed less than comparison (result is either 0 or 337 ///< some target-specific non-zero value). 338 LTE, ///< Signed less than or equal comparison (result is either 0 or 339 ///< some target-specific non-zero value). 340 Mod, ///< Signed remainder. 341 Mul, ///< Multiplication. 342 NE, ///< Inequality comparison. 343 Or, ///< Bitwise or. 344 Shl, ///< Shift left. 345 Shr, ///< Shift right (arithmetic or logical, depending on target) 346 Sub, ///< Subtraction. 347 Xor ///< Bitwise exclusive or. 348 }; 349 350private: 351 Opcode Op; 352 const MCExpr *LHS, *RHS; 353 354 MCBinaryExpr(Opcode _Op, const MCExpr *_LHS, const MCExpr *_RHS) 355 : MCExpr(MCExpr::Binary), Op(_Op), LHS(_LHS), RHS(_RHS) {} 356 357public: 358 /// @name Construction 359 /// @{ 360 361 static const MCBinaryExpr *Create(Opcode Op, const MCExpr *LHS, 362 const MCExpr *RHS, MCContext &Ctx); 363 static const MCBinaryExpr *CreateAdd(const MCExpr *LHS, const MCExpr *RHS, 364 MCContext &Ctx) { 365 return Create(Add, LHS, RHS, Ctx); 366 } 367 static const MCBinaryExpr *CreateAnd(const MCExpr *LHS, const MCExpr *RHS, 368 MCContext &Ctx) { 369 return Create(And, LHS, RHS, Ctx); 370 } 371 static const MCBinaryExpr *CreateDiv(const MCExpr *LHS, const MCExpr *RHS, 372 MCContext &Ctx) { 373 return Create(Div, LHS, RHS, Ctx); 374 } 375 static const MCBinaryExpr *CreateEQ(const MCExpr *LHS, const MCExpr *RHS, 376 MCContext &Ctx) { 377 return Create(EQ, LHS, RHS, Ctx); 378 } 379 static const MCBinaryExpr *CreateGT(const MCExpr *LHS, const MCExpr *RHS, 380 MCContext &Ctx) { 381 return Create(GT, LHS, RHS, Ctx); 382 } 383 static const MCBinaryExpr *CreateGTE(const MCExpr *LHS, const MCExpr *RHS, 384 MCContext &Ctx) { 385 return Create(GTE, LHS, RHS, Ctx); 386 } 387 static const MCBinaryExpr *CreateLAnd(const MCExpr *LHS, const MCExpr *RHS, 388 MCContext &Ctx) { 389 return Create(LAnd, LHS, RHS, Ctx); 390 } 391 static const MCBinaryExpr *CreateLOr(const MCExpr *LHS, const MCExpr *RHS, 392 MCContext &Ctx) { 393 return Create(LOr, LHS, RHS, Ctx); 394 } 395 static const MCBinaryExpr *CreateLT(const MCExpr *LHS, const MCExpr *RHS, 396 MCContext &Ctx) { 397 return Create(LT, LHS, RHS, Ctx); 398 } 399 static const MCBinaryExpr *CreateLTE(const MCExpr *LHS, const MCExpr *RHS, 400 MCContext &Ctx) { 401 return Create(LTE, LHS, RHS, Ctx); 402 } 403 static const MCBinaryExpr *CreateMod(const MCExpr *LHS, const MCExpr *RHS, 404 MCContext &Ctx) { 405 return Create(Mod, LHS, RHS, Ctx); 406 } 407 static const MCBinaryExpr *CreateMul(const MCExpr *LHS, const MCExpr *RHS, 408 MCContext &Ctx) { 409 return Create(Mul, LHS, RHS, Ctx); 410 } 411 static const MCBinaryExpr *CreateNE(const MCExpr *LHS, const MCExpr *RHS, 412 MCContext &Ctx) { 413 return Create(NE, LHS, RHS, Ctx); 414 } 415 static const MCBinaryExpr *CreateOr(const MCExpr *LHS, const MCExpr *RHS, 416 MCContext &Ctx) { 417 return Create(Or, LHS, RHS, Ctx); 418 } 419 static const MCBinaryExpr *CreateShl(const MCExpr *LHS, const MCExpr *RHS, 420 MCContext &Ctx) { 421 return Create(Shl, LHS, RHS, Ctx); 422 } 423 static const MCBinaryExpr *CreateShr(const MCExpr *LHS, const MCExpr *RHS, 424 MCContext &Ctx) { 425 return Create(Shr, LHS, RHS, Ctx); 426 } 427 static const MCBinaryExpr *CreateSub(const MCExpr *LHS, const MCExpr *RHS, 428 MCContext &Ctx) { 429 return Create(Sub, LHS, RHS, Ctx); 430 } 431 static const MCBinaryExpr *CreateXor(const MCExpr *LHS, const MCExpr *RHS, 432 MCContext &Ctx) { 433 return Create(Xor, LHS, RHS, Ctx); 434 } 435 436 /// @} 437 /// @name Accessors 438 /// @{ 439 440 /// getOpcode - Get the kind of this binary expression. 441 Opcode getOpcode() const { return Op; } 442 443 /// getLHS - Get the left-hand side expression of the binary operator. 444 const MCExpr *getLHS() const { return LHS; } 445 446 /// getRHS - Get the right-hand side expression of the binary operator. 447 const MCExpr *getRHS() const { return RHS; } 448 449 /// @} 450 451 static bool classof(const MCExpr *E) { 452 return E->getKind() == MCExpr::Binary; 453 } 454}; 455 456/// MCTargetExpr - This is an extension point for target-specific MCExpr 457/// subclasses to implement. 458/// 459/// NOTE: All subclasses are required to have trivial destructors because 460/// MCExprs are bump pointer allocated and not destructed. 461class MCTargetExpr : public MCExpr { 462 virtual void anchor(); 463protected: 464 MCTargetExpr() : MCExpr(Target) {} 465 virtual ~MCTargetExpr() {} 466public: 467 468 virtual void PrintImpl(raw_ostream &OS) const = 0; 469 virtual bool EvaluateAsRelocatableImpl(MCValue &Res, 470 const MCAsmLayout *Layout) const = 0; 471 virtual void AddValueSymbols(MCAssembler *) const = 0; 472 virtual const MCSection *FindAssociatedSection() const = 0; 473 474 static bool classof(const MCExpr *E) { 475 return E->getKind() == MCExpr::Target; 476 } 477}; 478 479} // end namespace llvm 480 481#endif 482