MCExpr.h revision 3faac0a78c7a70d3dcd2af102a132bb9da2d639c
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, 172 173 VK_PPC_TOC, 174 VK_PPC_DARWIN_HA16, // ha16(symbol) 175 VK_PPC_DARWIN_LO16, // lo16(symbol) 176 VK_PPC_GAS_HA16, // symbol@ha 177 VK_PPC_GAS_LO16, // symbol@l 178 179 VK_Mips_None, 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 210public: 211 /// @name Construction 212 /// @{ 213 214 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, MCContext &Ctx) { 215 return MCSymbolRefExpr::Create(Symbol, VK_None, Ctx); 216 } 217 218 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, VariantKind Kind, 219 MCContext &Ctx); 220 static const MCSymbolRefExpr *Create(StringRef Name, VariantKind Kind, 221 MCContext &Ctx); 222 223 /// @} 224 /// @name Accessors 225 /// @{ 226 227 const MCSymbol &getSymbol() const { return *Symbol; } 228 229 VariantKind getKind() const { return Kind; } 230 231 /// @} 232 /// @name Static Utility Functions 233 /// @{ 234 235 static StringRef getVariantKindName(VariantKind Kind); 236 237 static VariantKind getVariantKindForName(StringRef Name); 238 239 /// @} 240 241 static bool classof(const MCExpr *E) { 242 return E->getKind() == MCExpr::SymbolRef; 243 } 244 static bool classof(const MCSymbolRefExpr *) { return true; } 245}; 246 247/// MCUnaryExpr - Unary assembler expressions. 248class MCUnaryExpr : public MCExpr { 249public: 250 enum Opcode { 251 LNot, ///< Logical negation. 252 Minus, ///< Unary minus. 253 Not, ///< Bitwise negation. 254 Plus ///< Unary plus. 255 }; 256 257private: 258 Opcode Op; 259 const MCExpr *Expr; 260 261 MCUnaryExpr(Opcode _Op, const MCExpr *_Expr) 262 : MCExpr(MCExpr::Unary), Op(_Op), Expr(_Expr) {} 263 264public: 265 /// @name Construction 266 /// @{ 267 268 static const MCUnaryExpr *Create(Opcode Op, const MCExpr *Expr, 269 MCContext &Ctx); 270 static const MCUnaryExpr *CreateLNot(const MCExpr *Expr, MCContext &Ctx) { 271 return Create(LNot, Expr, Ctx); 272 } 273 static const MCUnaryExpr *CreateMinus(const MCExpr *Expr, MCContext &Ctx) { 274 return Create(Minus, Expr, Ctx); 275 } 276 static const MCUnaryExpr *CreateNot(const MCExpr *Expr, MCContext &Ctx) { 277 return Create(Not, Expr, Ctx); 278 } 279 static const MCUnaryExpr *CreatePlus(const MCExpr *Expr, MCContext &Ctx) { 280 return Create(Plus, Expr, Ctx); 281 } 282 283 /// @} 284 /// @name Accessors 285 /// @{ 286 287 /// getOpcode - Get the kind of this unary expression. 288 Opcode getOpcode() const { return Op; } 289 290 /// getSubExpr - Get the child of this unary expression. 291 const MCExpr *getSubExpr() const { return Expr; } 292 293 /// @} 294 295 static bool classof(const MCExpr *E) { 296 return E->getKind() == MCExpr::Unary; 297 } 298 static bool classof(const MCUnaryExpr *) { return true; } 299}; 300 301/// MCBinaryExpr - Binary assembler expressions. 302class MCBinaryExpr : public MCExpr { 303public: 304 enum Opcode { 305 Add, ///< Addition. 306 And, ///< Bitwise and. 307 Div, ///< Signed division. 308 EQ, ///< Equality comparison. 309 GT, ///< Signed greater than comparison (result is either 0 or some 310 ///< target-specific non-zero value) 311 GTE, ///< Signed greater than or equal comparison (result is either 0 or 312 ///< some target-specific non-zero value). 313 LAnd, ///< Logical and. 314 LOr, ///< Logical or. 315 LT, ///< Signed less than comparison (result is either 0 or 316 ///< some target-specific non-zero value). 317 LTE, ///< Signed less than or equal comparison (result is either 0 or 318 ///< some target-specific non-zero value). 319 Mod, ///< Signed remainder. 320 Mul, ///< Multiplication. 321 NE, ///< Inequality comparison. 322 Or, ///< Bitwise or. 323 Shl, ///< Shift left. 324 Shr, ///< Shift right (arithmetic or logical, depending on target) 325 Sub, ///< Subtraction. 326 Xor ///< Bitwise exclusive or. 327 }; 328 329private: 330 Opcode Op; 331 const MCExpr *LHS, *RHS; 332 333 MCBinaryExpr(Opcode _Op, const MCExpr *_LHS, const MCExpr *_RHS) 334 : MCExpr(MCExpr::Binary), Op(_Op), LHS(_LHS), RHS(_RHS) {} 335 336public: 337 /// @name Construction 338 /// @{ 339 340 static const MCBinaryExpr *Create(Opcode Op, const MCExpr *LHS, 341 const MCExpr *RHS, MCContext &Ctx); 342 static const MCBinaryExpr *CreateAdd(const MCExpr *LHS, const MCExpr *RHS, 343 MCContext &Ctx) { 344 return Create(Add, LHS, RHS, Ctx); 345 } 346 static const MCBinaryExpr *CreateAnd(const MCExpr *LHS, const MCExpr *RHS, 347 MCContext &Ctx) { 348 return Create(And, LHS, RHS, Ctx); 349 } 350 static const MCBinaryExpr *CreateDiv(const MCExpr *LHS, const MCExpr *RHS, 351 MCContext &Ctx) { 352 return Create(Div, LHS, RHS, Ctx); 353 } 354 static const MCBinaryExpr *CreateEQ(const MCExpr *LHS, const MCExpr *RHS, 355 MCContext &Ctx) { 356 return Create(EQ, LHS, RHS, Ctx); 357 } 358 static const MCBinaryExpr *CreateGT(const MCExpr *LHS, const MCExpr *RHS, 359 MCContext &Ctx) { 360 return Create(GT, LHS, RHS, Ctx); 361 } 362 static const MCBinaryExpr *CreateGTE(const MCExpr *LHS, const MCExpr *RHS, 363 MCContext &Ctx) { 364 return Create(GTE, LHS, RHS, Ctx); 365 } 366 static const MCBinaryExpr *CreateLAnd(const MCExpr *LHS, const MCExpr *RHS, 367 MCContext &Ctx) { 368 return Create(LAnd, LHS, RHS, Ctx); 369 } 370 static const MCBinaryExpr *CreateLOr(const MCExpr *LHS, const MCExpr *RHS, 371 MCContext &Ctx) { 372 return Create(LOr, LHS, RHS, Ctx); 373 } 374 static const MCBinaryExpr *CreateLT(const MCExpr *LHS, const MCExpr *RHS, 375 MCContext &Ctx) { 376 return Create(LT, LHS, RHS, Ctx); 377 } 378 static const MCBinaryExpr *CreateLTE(const MCExpr *LHS, const MCExpr *RHS, 379 MCContext &Ctx) { 380 return Create(LTE, LHS, RHS, Ctx); 381 } 382 static const MCBinaryExpr *CreateMod(const MCExpr *LHS, const MCExpr *RHS, 383 MCContext &Ctx) { 384 return Create(Mod, LHS, RHS, Ctx); 385 } 386 static const MCBinaryExpr *CreateMul(const MCExpr *LHS, const MCExpr *RHS, 387 MCContext &Ctx) { 388 return Create(Mul, LHS, RHS, Ctx); 389 } 390 static const MCBinaryExpr *CreateNE(const MCExpr *LHS, const MCExpr *RHS, 391 MCContext &Ctx) { 392 return Create(NE, LHS, RHS, Ctx); 393 } 394 static const MCBinaryExpr *CreateOr(const MCExpr *LHS, const MCExpr *RHS, 395 MCContext &Ctx) { 396 return Create(Or, LHS, RHS, Ctx); 397 } 398 static const MCBinaryExpr *CreateShl(const MCExpr *LHS, const MCExpr *RHS, 399 MCContext &Ctx) { 400 return Create(Shl, LHS, RHS, Ctx); 401 } 402 static const MCBinaryExpr *CreateShr(const MCExpr *LHS, const MCExpr *RHS, 403 MCContext &Ctx) { 404 return Create(Shr, LHS, RHS, Ctx); 405 } 406 static const MCBinaryExpr *CreateSub(const MCExpr *LHS, const MCExpr *RHS, 407 MCContext &Ctx) { 408 return Create(Sub, LHS, RHS, Ctx); 409 } 410 static const MCBinaryExpr *CreateXor(const MCExpr *LHS, const MCExpr *RHS, 411 MCContext &Ctx) { 412 return Create(Xor, LHS, RHS, Ctx); 413 } 414 415 /// @} 416 /// @name Accessors 417 /// @{ 418 419 /// getOpcode - Get the kind of this binary expression. 420 Opcode getOpcode() const { return Op; } 421 422 /// getLHS - Get the left-hand side expression of the binary operator. 423 const MCExpr *getLHS() const { return LHS; } 424 425 /// getRHS - Get the right-hand side expression of the binary operator. 426 const MCExpr *getRHS() const { return RHS; } 427 428 /// @} 429 430 static bool classof(const MCExpr *E) { 431 return E->getKind() == MCExpr::Binary; 432 } 433 static bool classof(const MCBinaryExpr *) { return true; } 434}; 435 436/// MCTargetExpr - This is an extension point for target-specific MCExpr 437/// subclasses to implement. 438/// 439/// NOTE: All subclasses are required to have trivial destructors because 440/// MCExprs are bump pointer allocated and not destructed. 441class MCTargetExpr : public MCExpr { 442 virtual void Anchor(); 443protected: 444 MCTargetExpr() : MCExpr(Target) {} 445 virtual ~MCTargetExpr() {} 446public: 447 448 virtual void PrintImpl(raw_ostream &OS) const = 0; 449 virtual bool EvaluateAsRelocatableImpl(MCValue &Res, 450 const MCAsmLayout *Layout) const = 0; 451 virtual void AddValueSymbols(MCAssembler *) const = 0; 452 virtual const MCSection *FindAssociatedSection() const = 0; 453 454 static bool classof(const MCExpr *E) { 455 return E->getKind() == MCExpr::Target; 456 } 457 static bool classof(const MCTargetExpr *) { return true; } 458}; 459 460} // end namespace llvm 461 462#endif 463