MCExpr.h revision 34982576a43887e7f062ed0a3571af2cbab003f3
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 MCAsmInfo; 19class MCAsmLayout; 20class MCAssembler; 21class MCContext; 22class MCSection; 23class MCSectionData; 24class MCSymbol; 25class MCValue; 26class raw_ostream; 27class StringRef; 28typedef DenseMap<const MCSectionData*, uint64_t> SectionAddrMap; 29 30/// MCExpr - Base class for the full range of assembler expressions which are 31/// needed for parsing. 32class MCExpr { 33public: 34 enum ExprKind { 35 Binary, ///< Binary expressions. 36 Constant, ///< Constant expressions. 37 SymbolRef, ///< References to labels and assigned expressions. 38 Unary, ///< Unary expressions. 39 Target ///< Target specific expression. 40 }; 41 42private: 43 ExprKind Kind; 44 45 MCExpr(const MCExpr&); // DO NOT IMPLEMENT 46 void operator=(const MCExpr&); // DO NOT IMPLEMENT 47 48 bool EvaluateAsAbsolute(int64_t &Res, const MCAssembler *Asm, 49 const MCAsmLayout *Layout, 50 const SectionAddrMap *Addrs) const; 51protected: 52 explicit MCExpr(ExprKind _Kind) : Kind(_Kind) {} 53 54 bool EvaluateAsRelocatableImpl(MCValue &Res, const MCAssembler *Asm, 55 const MCAsmLayout *Layout, 56 const SectionAddrMap *Addrs, 57 bool InSet) const; 58public: 59 /// @name Accessors 60 /// @{ 61 62 ExprKind getKind() const { return Kind; } 63 64 /// @} 65 /// @name Utility Methods 66 /// @{ 67 68 void print(raw_ostream &OS) const; 69 void dump() const; 70 71 /// @} 72 /// @name Expression Evaluation 73 /// @{ 74 75 /// EvaluateAsAbsolute - Try to evaluate the expression to an absolute value. 76 /// 77 /// @param Res - The absolute value, if evaluation succeeds. 78 /// @param Layout - The assembler layout object to use for evaluating symbol 79 /// values. If not given, then only non-symbolic expressions will be 80 /// evaluated. 81 /// @result - True on success. 82 bool EvaluateAsAbsolute(int64_t &Res) const; 83 bool EvaluateAsAbsolute(int64_t &Res, const MCAssembler &Asm) const; 84 bool EvaluateAsAbsolute(int64_t &Res, const MCAsmLayout &Layout) const; 85 bool EvaluateAsAbsolute(int64_t &Res, const MCAsmLayout &Layout, 86 const SectionAddrMap &Addrs) const; 87 88 /// EvaluateAsRelocatable - Try to evaluate the expression to a relocatable 89 /// value, i.e. an expression of the fixed form (a - b + constant). 90 /// 91 /// @param Res - The relocatable value, if evaluation succeeds. 92 /// @param Layout - The assembler layout object to use for evaluating values. 93 /// @result - True on success. 94 bool EvaluateAsRelocatable(MCValue &Res, const MCAsmLayout &Layout) const; 95 96 /// FindAssociatedSection - Find the "associated section" for this expression, 97 /// which is currently defined as the absolute section for constants, or 98 /// otherwise the section associated with the first defined symbol in the 99 /// expression. 100 const MCSection *FindAssociatedSection() const; 101 102 /// @} 103 104 static bool classof(const MCExpr *) { return true; } 105}; 106 107inline raw_ostream &operator<<(raw_ostream &OS, const MCExpr &E) { 108 E.print(OS); 109 return OS; 110} 111 112//// MCConstantExpr - Represent a constant integer expression. 113class MCConstantExpr : public MCExpr { 114 int64_t Value; 115 116 explicit MCConstantExpr(int64_t _Value) 117 : MCExpr(MCExpr::Constant), Value(_Value) {} 118 119public: 120 /// @name Construction 121 /// @{ 122 123 static const MCConstantExpr *Create(int64_t Value, MCContext &Ctx); 124 125 /// @} 126 /// @name Accessors 127 /// @{ 128 129 int64_t getValue() const { return Value; } 130 131 /// @} 132 133 static bool classof(const MCExpr *E) { 134 return E->getKind() == MCExpr::Constant; 135 } 136 static bool classof(const MCConstantExpr *) { return true; } 137}; 138 139/// MCSymbolRefExpr - Represent a reference to a symbol from inside an 140/// expression. 141/// 142/// A symbol reference in an expression may be a use of a label, a use of an 143/// assembler variable (defined constant), or constitute an implicit definition 144/// of the symbol as external. 145class MCSymbolRefExpr : public MCExpr { 146public: 147 enum VariantKind { 148 VK_None, 149 VK_Invalid, 150 151 VK_GOT, 152 VK_GOTOFF, 153 VK_GOTPCREL, 154 VK_GOTTPOFF, 155 VK_INDNTPOFF, 156 VK_NTPOFF, 157 VK_GOTNTPOFF, 158 VK_PLT, 159 VK_TLSGD, 160 VK_TLSLD, 161 VK_TLSLDM, 162 VK_TPOFF, 163 VK_DTPOFF, 164 VK_TLVP, // Mach-O thread local variable relocation 165 // FIXME: We'd really like to use the generic Kinds listed above for these. 166 VK_ARM_PLT, // ARM-style PLT references. i.e., (PLT) instead of @PLT 167 VK_ARM_TLSGD, // ditto for TLSGD, GOT, GOTOFF, TPOFF and GOTTPOFF 168 VK_ARM_GOT, 169 VK_ARM_GOTOFF, 170 VK_ARM_TPOFF, 171 VK_ARM_GOTTPOFF, 172 VK_ARM_TARGET1, 173 174 VK_PPC_TOC, 175 VK_PPC_DARWIN_HA16, // ha16(symbol) 176 VK_PPC_DARWIN_LO16, // lo16(symbol) 177 VK_PPC_GAS_HA16, // symbol@ha 178 VK_PPC_GAS_LO16, // symbol@l 179 180 VK_Mips_GPREL, 181 VK_Mips_GOT_CALL, 182 VK_Mips_GOT16, 183 VK_Mips_GOT, 184 VK_Mips_ABS_HI, 185 VK_Mips_ABS_LO, 186 VK_Mips_TLSGD, 187 VK_Mips_TLSLDM, 188 VK_Mips_DTPREL_HI, 189 VK_Mips_DTPREL_LO, 190 VK_Mips_GOTTPREL, 191 VK_Mips_TPREL_HI, 192 VK_Mips_TPREL_LO, 193 VK_Mips_GPOFF_HI, 194 VK_Mips_GPOFF_LO, 195 VK_Mips_GOT_DISP, 196 VK_Mips_GOT_PAGE, 197 VK_Mips_GOT_OFST 198 }; 199 200private: 201 /// The symbol being referenced. 202 const MCSymbol *Symbol; 203 204 /// The symbol reference modifier. 205 const VariantKind Kind; 206 207 explicit MCSymbolRefExpr(const MCSymbol *_Symbol, VariantKind _Kind) 208 : MCExpr(MCExpr::SymbolRef), Symbol(_Symbol), Kind(_Kind) { 209 assert(Symbol); 210 } 211 212public: 213 /// @name Construction 214 /// @{ 215 216 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, MCContext &Ctx) { 217 return MCSymbolRefExpr::Create(Symbol, VK_None, Ctx); 218 } 219 220 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, VariantKind Kind, 221 MCContext &Ctx); 222 static const MCSymbolRefExpr *Create(StringRef Name, VariantKind Kind, 223 MCContext &Ctx); 224 225 /// @} 226 /// @name Accessors 227 /// @{ 228 229 const MCSymbol &getSymbol() const { return *Symbol; } 230 231 VariantKind getKind() const { return Kind; } 232 233 /// @} 234 /// @name Static Utility Functions 235 /// @{ 236 237 static StringRef getVariantKindName(VariantKind Kind); 238 239 static VariantKind getVariantKindForName(StringRef Name); 240 241 /// @} 242 243 static bool classof(const MCExpr *E) { 244 return E->getKind() == MCExpr::SymbolRef; 245 } 246 static bool classof(const MCSymbolRefExpr *) { return true; } 247}; 248 249/// MCUnaryExpr - Unary assembler expressions. 250class MCUnaryExpr : public MCExpr { 251public: 252 enum Opcode { 253 LNot, ///< Logical negation. 254 Minus, ///< Unary minus. 255 Not, ///< Bitwise negation. 256 Plus ///< Unary plus. 257 }; 258 259private: 260 Opcode Op; 261 const MCExpr *Expr; 262 263 MCUnaryExpr(Opcode _Op, const MCExpr *_Expr) 264 : MCExpr(MCExpr::Unary), Op(_Op), Expr(_Expr) {} 265 266public: 267 /// @name Construction 268 /// @{ 269 270 static const MCUnaryExpr *Create(Opcode Op, const MCExpr *Expr, 271 MCContext &Ctx); 272 static const MCUnaryExpr *CreateLNot(const MCExpr *Expr, MCContext &Ctx) { 273 return Create(LNot, Expr, Ctx); 274 } 275 static const MCUnaryExpr *CreateMinus(const MCExpr *Expr, MCContext &Ctx) { 276 return Create(Minus, Expr, Ctx); 277 } 278 static const MCUnaryExpr *CreateNot(const MCExpr *Expr, MCContext &Ctx) { 279 return Create(Not, Expr, Ctx); 280 } 281 static const MCUnaryExpr *CreatePlus(const MCExpr *Expr, MCContext &Ctx) { 282 return Create(Plus, Expr, Ctx); 283 } 284 285 /// @} 286 /// @name Accessors 287 /// @{ 288 289 /// getOpcode - Get the kind of this unary expression. 290 Opcode getOpcode() const { return Op; } 291 292 /// getSubExpr - Get the child of this unary expression. 293 const MCExpr *getSubExpr() const { return Expr; } 294 295 /// @} 296 297 static bool classof(const MCExpr *E) { 298 return E->getKind() == MCExpr::Unary; 299 } 300 static bool classof(const MCUnaryExpr *) { return true; } 301}; 302 303/// MCBinaryExpr - Binary assembler expressions. 304class MCBinaryExpr : public MCExpr { 305public: 306 enum Opcode { 307 Add, ///< Addition. 308 And, ///< Bitwise and. 309 Div, ///< Signed division. 310 EQ, ///< Equality comparison. 311 GT, ///< Signed greater than comparison (result is either 0 or some 312 ///< target-specific non-zero value) 313 GTE, ///< Signed greater than or equal comparison (result is either 0 or 314 ///< some target-specific non-zero value). 315 LAnd, ///< Logical and. 316 LOr, ///< Logical or. 317 LT, ///< Signed less than comparison (result is either 0 or 318 ///< some target-specific non-zero value). 319 LTE, ///< Signed less than or equal comparison (result is either 0 or 320 ///< some target-specific non-zero value). 321 Mod, ///< Signed remainder. 322 Mul, ///< Multiplication. 323 NE, ///< Inequality comparison. 324 Or, ///< Bitwise or. 325 Shl, ///< Shift left. 326 Shr, ///< Shift right (arithmetic or logical, depending on target) 327 Sub, ///< Subtraction. 328 Xor ///< Bitwise exclusive or. 329 }; 330 331private: 332 Opcode Op; 333 const MCExpr *LHS, *RHS; 334 335 MCBinaryExpr(Opcode _Op, const MCExpr *_LHS, const MCExpr *_RHS) 336 : MCExpr(MCExpr::Binary), Op(_Op), LHS(_LHS), RHS(_RHS) {} 337 338public: 339 /// @name Construction 340 /// @{ 341 342 static const MCBinaryExpr *Create(Opcode Op, const MCExpr *LHS, 343 const MCExpr *RHS, MCContext &Ctx); 344 static const MCBinaryExpr *CreateAdd(const MCExpr *LHS, const MCExpr *RHS, 345 MCContext &Ctx) { 346 return Create(Add, LHS, RHS, Ctx); 347 } 348 static const MCBinaryExpr *CreateAnd(const MCExpr *LHS, const MCExpr *RHS, 349 MCContext &Ctx) { 350 return Create(And, LHS, RHS, Ctx); 351 } 352 static const MCBinaryExpr *CreateDiv(const MCExpr *LHS, const MCExpr *RHS, 353 MCContext &Ctx) { 354 return Create(Div, LHS, RHS, Ctx); 355 } 356 static const MCBinaryExpr *CreateEQ(const MCExpr *LHS, const MCExpr *RHS, 357 MCContext &Ctx) { 358 return Create(EQ, LHS, RHS, Ctx); 359 } 360 static const MCBinaryExpr *CreateGT(const MCExpr *LHS, const MCExpr *RHS, 361 MCContext &Ctx) { 362 return Create(GT, LHS, RHS, Ctx); 363 } 364 static const MCBinaryExpr *CreateGTE(const MCExpr *LHS, const MCExpr *RHS, 365 MCContext &Ctx) { 366 return Create(GTE, LHS, RHS, Ctx); 367 } 368 static const MCBinaryExpr *CreateLAnd(const MCExpr *LHS, const MCExpr *RHS, 369 MCContext &Ctx) { 370 return Create(LAnd, LHS, RHS, Ctx); 371 } 372 static const MCBinaryExpr *CreateLOr(const MCExpr *LHS, const MCExpr *RHS, 373 MCContext &Ctx) { 374 return Create(LOr, LHS, RHS, Ctx); 375 } 376 static const MCBinaryExpr *CreateLT(const MCExpr *LHS, const MCExpr *RHS, 377 MCContext &Ctx) { 378 return Create(LT, LHS, RHS, Ctx); 379 } 380 static const MCBinaryExpr *CreateLTE(const MCExpr *LHS, const MCExpr *RHS, 381 MCContext &Ctx) { 382 return Create(LTE, LHS, RHS, Ctx); 383 } 384 static const MCBinaryExpr *CreateMod(const MCExpr *LHS, const MCExpr *RHS, 385 MCContext &Ctx) { 386 return Create(Mod, LHS, RHS, Ctx); 387 } 388 static const MCBinaryExpr *CreateMul(const MCExpr *LHS, const MCExpr *RHS, 389 MCContext &Ctx) { 390 return Create(Mul, LHS, RHS, Ctx); 391 } 392 static const MCBinaryExpr *CreateNE(const MCExpr *LHS, const MCExpr *RHS, 393 MCContext &Ctx) { 394 return Create(NE, LHS, RHS, Ctx); 395 } 396 static const MCBinaryExpr *CreateOr(const MCExpr *LHS, const MCExpr *RHS, 397 MCContext &Ctx) { 398 return Create(Or, LHS, RHS, Ctx); 399 } 400 static const MCBinaryExpr *CreateShl(const MCExpr *LHS, const MCExpr *RHS, 401 MCContext &Ctx) { 402 return Create(Shl, LHS, RHS, Ctx); 403 } 404 static const MCBinaryExpr *CreateShr(const MCExpr *LHS, const MCExpr *RHS, 405 MCContext &Ctx) { 406 return Create(Shr, LHS, RHS, Ctx); 407 } 408 static const MCBinaryExpr *CreateSub(const MCExpr *LHS, const MCExpr *RHS, 409 MCContext &Ctx) { 410 return Create(Sub, LHS, RHS, Ctx); 411 } 412 static const MCBinaryExpr *CreateXor(const MCExpr *LHS, const MCExpr *RHS, 413 MCContext &Ctx) { 414 return Create(Xor, LHS, RHS, Ctx); 415 } 416 417 /// @} 418 /// @name Accessors 419 /// @{ 420 421 /// getOpcode - Get the kind of this binary expression. 422 Opcode getOpcode() const { return Op; } 423 424 /// getLHS - Get the left-hand side expression of the binary operator. 425 const MCExpr *getLHS() const { return LHS; } 426 427 /// getRHS - Get the right-hand side expression of the binary operator. 428 const MCExpr *getRHS() const { return RHS; } 429 430 /// @} 431 432 static bool classof(const MCExpr *E) { 433 return E->getKind() == MCExpr::Binary; 434 } 435 static bool classof(const MCBinaryExpr *) { return true; } 436}; 437 438/// MCTargetExpr - This is an extension point for target-specific MCExpr 439/// subclasses to implement. 440/// 441/// NOTE: All subclasses are required to have trivial destructors because 442/// MCExprs are bump pointer allocated and not destructed. 443class MCTargetExpr : public MCExpr { 444 virtual void Anchor(); 445protected: 446 MCTargetExpr() : MCExpr(Target) {} 447 virtual ~MCTargetExpr() {} 448public: 449 450 virtual void PrintImpl(raw_ostream &OS) const = 0; 451 virtual bool EvaluateAsRelocatableImpl(MCValue &Res, 452 const MCAsmLayout *Layout) const = 0; 453 virtual void AddValueSymbols(MCAssembler *) const = 0; 454 virtual const MCSection *FindAssociatedSection() const = 0; 455 456 static bool classof(const MCExpr *E) { 457 return E->getKind() == MCExpr::Target; 458 } 459 static bool classof(const MCTargetExpr *) { return true; } 460}; 461 462} // end namespace llvm 463 464#endif 465