1 //===- MCExpr.h - Assembly Level Expressions --------------------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef LLVM_MC_MCEXPR_H 10 #define LLVM_MC_MCEXPR_H 11 12 #include "llvm/ADT/DenseMap.h" 13 #include "llvm/Support/SMLoc.h" 14 #include <cstdint> 15 16 namespace llvm { 17 18 class MCAsmInfo; 19 class MCAsmLayout; 20 class MCAssembler; 21 class MCContext; 22 class MCFixup; 23 class MCFragment; 24 class MCSection; 25 class MCStreamer; 26 class MCSymbol; 27 class MCValue; 28 class raw_ostream; 29 class StringRef; 30 31 using SectionAddrMap = DenseMap<const MCSection *, uint64_t>; 32 33 /// Base class for the full range of assembler expressions which are 34 /// needed for parsing. 35 class MCExpr { 36 public: 37 enum ExprKind { 38 Binary, ///< Binary expressions. 39 Constant, ///< Constant expressions. 40 SymbolRef, ///< References to labels and assigned expressions. 41 Unary, ///< Unary expressions. 42 Target ///< Target specific expression. 43 }; 44 45 private: 46 ExprKind Kind; 47 SMLoc Loc; 48 49 bool evaluateAsAbsolute(int64_t &Res, const MCAssembler *Asm, 50 const MCAsmLayout *Layout, 51 const SectionAddrMap *Addrs, bool InSet) const; 52 53 protected: MCExpr(ExprKind Kind,SMLoc Loc)54 explicit MCExpr(ExprKind Kind, SMLoc Loc) : Kind(Kind), Loc(Loc) {} 55 56 bool evaluateAsRelocatableImpl(MCValue &Res, const MCAssembler *Asm, 57 const MCAsmLayout *Layout, 58 const MCFixup *Fixup, 59 const SectionAddrMap *Addrs, bool InSet) const; 60 61 public: 62 MCExpr(const MCExpr &) = delete; 63 MCExpr &operator=(const MCExpr &) = delete; 64 65 /// \name Accessors 66 /// @{ 67 getKind()68 ExprKind getKind() const { return Kind; } getLoc()69 SMLoc getLoc() const { return Loc; } 70 71 /// @} 72 /// \name Utility Methods 73 /// @{ 74 75 void print(raw_ostream &OS, const MCAsmInfo *MAI, 76 bool InParens = false) const; 77 void dump() const; 78 79 /// @} 80 /// \name Expression Evaluation 81 /// @{ 82 83 /// Try to evaluate the expression to an absolute value. 84 /// 85 /// \param Res - The absolute value, if evaluation succeeds. 86 /// \param Layout - The assembler layout object to use for evaluating symbol 87 /// values. If not given, then only non-symbolic expressions will be 88 /// evaluated. 89 /// \return - True on success. 90 bool evaluateAsAbsolute(int64_t &Res, const MCAsmLayout &Layout, 91 const SectionAddrMap &Addrs) const; 92 bool evaluateAsAbsolute(int64_t &Res) const; 93 bool evaluateAsAbsolute(int64_t &Res, const MCAssembler &Asm) const; 94 bool evaluateAsAbsolute(int64_t &Res, const MCAssembler *Asm) const; 95 bool evaluateAsAbsolute(int64_t &Res, const MCAsmLayout &Layout) const; 96 97 bool evaluateKnownAbsolute(int64_t &Res, const MCAsmLayout &Layout) const; 98 99 /// Try to evaluate the expression to a relocatable value, i.e. an 100 /// expression of the fixed form (a - b + constant). 101 /// 102 /// \param Res - The relocatable value, if evaluation succeeds. 103 /// \param Layout - The assembler layout object to use for evaluating values. 104 /// \param Fixup - The Fixup object if available. 105 /// \return - True on success. 106 bool evaluateAsRelocatable(MCValue &Res, const MCAsmLayout *Layout, 107 const MCFixup *Fixup) const; 108 109 /// Try to evaluate the expression to the form (a - b + constant) where 110 /// neither a nor b are variables. 111 /// 112 /// This is a more aggressive variant of evaluateAsRelocatable. The intended 113 /// use is for when relocations are not available, like the .size directive. 114 bool evaluateAsValue(MCValue &Res, const MCAsmLayout &Layout) const; 115 116 /// Find the "associated section" for this expression, which is 117 /// currently defined as the absolute section for constants, or 118 /// otherwise the section associated with the first defined symbol in the 119 /// expression. 120 MCFragment *findAssociatedFragment() const; 121 122 /// @} 123 }; 124 125 inline raw_ostream &operator<<(raw_ostream &OS, const MCExpr &E) { 126 E.print(OS, nullptr); 127 return OS; 128 } 129 130 //// Represent a constant integer expression. 131 class MCConstantExpr : public MCExpr { 132 int64_t Value; 133 bool PrintInHex = false; 134 MCConstantExpr(int64_t Value)135 explicit MCConstantExpr(int64_t Value) 136 : MCExpr(MCExpr::Constant, SMLoc()), Value(Value) {} 137 MCConstantExpr(int64_t Value,bool PrintInHex)138 MCConstantExpr(int64_t Value, bool PrintInHex) 139 : MCExpr(MCExpr::Constant, SMLoc()), Value(Value), 140 PrintInHex(PrintInHex) {} 141 142 public: 143 /// \name Construction 144 /// @{ 145 146 static const MCConstantExpr *create(int64_t Value, MCContext &Ctx, 147 bool PrintInHex = false); 148 149 /// @} 150 /// \name Accessors 151 /// @{ 152 getValue()153 int64_t getValue() const { return Value; } 154 useHexFormat()155 bool useHexFormat() const { return PrintInHex; } 156 157 /// @} 158 classof(const MCExpr * E)159 static bool classof(const MCExpr *E) { 160 return E->getKind() == MCExpr::Constant; 161 } 162 }; 163 164 /// Represent a reference to a symbol from inside an expression. 165 /// 166 /// A symbol reference in an expression may be a use of a label, a use of an 167 /// assembler variable (defined constant), or constitute an implicit definition 168 /// of the symbol as external. 169 class MCSymbolRefExpr : public MCExpr { 170 public: 171 enum VariantKind : uint16_t { 172 VK_None, 173 VK_Invalid, 174 175 VK_GOT, 176 VK_GOTOFF, 177 VK_GOTREL, 178 VK_GOTPCREL, 179 VK_GOTTPOFF, 180 VK_INDNTPOFF, 181 VK_NTPOFF, 182 VK_GOTNTPOFF, 183 VK_PLT, 184 VK_TLSGD, 185 VK_TLSLD, 186 VK_TLSLDM, 187 VK_TPOFF, 188 VK_DTPOFF, 189 VK_TLSCALL, // symbol(tlscall) 190 VK_TLSDESC, // symbol(tlsdesc) 191 VK_TLVP, // Mach-O thread local variable relocations 192 VK_TLVPPAGE, 193 VK_TLVPPAGEOFF, 194 VK_PAGE, 195 VK_PAGEOFF, 196 VK_GOTPAGE, 197 VK_GOTPAGEOFF, 198 VK_SECREL, 199 VK_SIZE, // symbol@SIZE 200 VK_WEAKREF, // The link between the symbols in .weakref foo, bar 201 202 VK_X86_ABS8, 203 204 VK_ARM_NONE, 205 VK_ARM_GOT_PREL, 206 VK_ARM_TARGET1, 207 VK_ARM_TARGET2, 208 VK_ARM_PREL31, 209 VK_ARM_SBREL, // symbol(sbrel) 210 VK_ARM_TLSLDO, // symbol(tlsldo) 211 VK_ARM_TLSDESCSEQ, 212 213 VK_AVR_NONE, 214 VK_AVR_LO8, 215 VK_AVR_HI8, 216 VK_AVR_HLO8, 217 VK_AVR_DIFF8, 218 VK_AVR_DIFF16, 219 VK_AVR_DIFF32, 220 221 VK_PPC_LO, // symbol@l 222 VK_PPC_HI, // symbol@h 223 VK_PPC_HA, // symbol@ha 224 VK_PPC_HIGH, // symbol@high 225 VK_PPC_HIGHA, // symbol@higha 226 VK_PPC_HIGHER, // symbol@higher 227 VK_PPC_HIGHERA, // symbol@highera 228 VK_PPC_HIGHEST, // symbol@highest 229 VK_PPC_HIGHESTA, // symbol@highesta 230 VK_PPC_GOT_LO, // symbol@got@l 231 VK_PPC_GOT_HI, // symbol@got@h 232 VK_PPC_GOT_HA, // symbol@got@ha 233 VK_PPC_TOCBASE, // symbol@tocbase 234 VK_PPC_TOC, // symbol@toc 235 VK_PPC_TOC_LO, // symbol@toc@l 236 VK_PPC_TOC_HI, // symbol@toc@h 237 VK_PPC_TOC_HA, // symbol@toc@ha 238 VK_PPC_U, // symbol@u 239 VK_PPC_L, // symbol@l 240 VK_PPC_DTPMOD, // symbol@dtpmod 241 VK_PPC_TPREL_LO, // symbol@tprel@l 242 VK_PPC_TPREL_HI, // symbol@tprel@h 243 VK_PPC_TPREL_HA, // symbol@tprel@ha 244 VK_PPC_TPREL_HIGH, // symbol@tprel@high 245 VK_PPC_TPREL_HIGHA, // symbol@tprel@higha 246 VK_PPC_TPREL_HIGHER, // symbol@tprel@higher 247 VK_PPC_TPREL_HIGHERA, // symbol@tprel@highera 248 VK_PPC_TPREL_HIGHEST, // symbol@tprel@highest 249 VK_PPC_TPREL_HIGHESTA, // symbol@tprel@highesta 250 VK_PPC_DTPREL_LO, // symbol@dtprel@l 251 VK_PPC_DTPREL_HI, // symbol@dtprel@h 252 VK_PPC_DTPREL_HA, // symbol@dtprel@ha 253 VK_PPC_DTPREL_HIGH, // symbol@dtprel@high 254 VK_PPC_DTPREL_HIGHA, // symbol@dtprel@higha 255 VK_PPC_DTPREL_HIGHER, // symbol@dtprel@higher 256 VK_PPC_DTPREL_HIGHERA, // symbol@dtprel@highera 257 VK_PPC_DTPREL_HIGHEST, // symbol@dtprel@highest 258 VK_PPC_DTPREL_HIGHESTA,// symbol@dtprel@highesta 259 VK_PPC_GOT_TPREL, // symbol@got@tprel 260 VK_PPC_GOT_TPREL_LO, // symbol@got@tprel@l 261 VK_PPC_GOT_TPREL_HI, // symbol@got@tprel@h 262 VK_PPC_GOT_TPREL_HA, // symbol@got@tprel@ha 263 VK_PPC_GOT_DTPREL, // symbol@got@dtprel 264 VK_PPC_GOT_DTPREL_LO, // symbol@got@dtprel@l 265 VK_PPC_GOT_DTPREL_HI, // symbol@got@dtprel@h 266 VK_PPC_GOT_DTPREL_HA, // symbol@got@dtprel@ha 267 VK_PPC_TLS, // symbol@tls 268 VK_PPC_GOT_TLSGD, // symbol@got@tlsgd 269 VK_PPC_GOT_TLSGD_LO, // symbol@got@tlsgd@l 270 VK_PPC_GOT_TLSGD_HI, // symbol@got@tlsgd@h 271 VK_PPC_GOT_TLSGD_HA, // symbol@got@tlsgd@ha 272 VK_PPC_TLSGD, // symbol@tlsgd 273 VK_PPC_GOT_TLSLD, // symbol@got@tlsld 274 VK_PPC_GOT_TLSLD_LO, // symbol@got@tlsld@l 275 VK_PPC_GOT_TLSLD_HI, // symbol@got@tlsld@h 276 VK_PPC_GOT_TLSLD_HA, // symbol@got@tlsld@ha 277 VK_PPC_TLSLD, // symbol@tlsld 278 VK_PPC_LOCAL, // symbol@local 279 280 VK_COFF_IMGREL32, // symbol@imgrel (image-relative) 281 282 VK_Hexagon_PCREL, 283 VK_Hexagon_LO16, 284 VK_Hexagon_HI16, 285 VK_Hexagon_GPREL, 286 VK_Hexagon_GD_GOT, 287 VK_Hexagon_LD_GOT, 288 VK_Hexagon_GD_PLT, 289 VK_Hexagon_LD_PLT, 290 VK_Hexagon_IE, 291 VK_Hexagon_IE_GOT, 292 293 VK_WASM_TYPEINDEX, // Reference to a symbol's type (signature) 294 VK_WASM_MBREL, // Memory address relative to memory base 295 VK_WASM_TBREL, // Table index relative to table bare 296 297 VK_AMDGPU_GOTPCREL32_LO, // symbol@gotpcrel32@lo 298 VK_AMDGPU_GOTPCREL32_HI, // symbol@gotpcrel32@hi 299 VK_AMDGPU_REL32_LO, // symbol@rel32@lo 300 VK_AMDGPU_REL32_HI, // symbol@rel32@hi 301 VK_AMDGPU_REL64, // symbol@rel64 302 VK_AMDGPU_ABS32_LO, // symbol@abs32@lo 303 VK_AMDGPU_ABS32_HI, // symbol@abs32@hi 304 305 VK_TPREL, 306 VK_DTPREL 307 }; 308 309 private: 310 /// The symbol reference modifier. 311 const VariantKind Kind; 312 313 /// Specifies how the variant kind should be printed. 314 const unsigned UseParensForSymbolVariant : 1; 315 316 // FIXME: Remove this bit. 317 const unsigned HasSubsectionsViaSymbols : 1; 318 319 /// The symbol being referenced. 320 const MCSymbol *Symbol; 321 322 explicit MCSymbolRefExpr(const MCSymbol *Symbol, VariantKind Kind, 323 const MCAsmInfo *MAI, SMLoc Loc = SMLoc()); 324 325 public: 326 /// \name Construction 327 /// @{ 328 create(const MCSymbol * Symbol,MCContext & Ctx)329 static const MCSymbolRefExpr *create(const MCSymbol *Symbol, MCContext &Ctx) { 330 return MCSymbolRefExpr::create(Symbol, VK_None, Ctx); 331 } 332 333 static const MCSymbolRefExpr *create(const MCSymbol *Symbol, VariantKind Kind, 334 MCContext &Ctx, SMLoc Loc = SMLoc()); 335 static const MCSymbolRefExpr *create(StringRef Name, VariantKind Kind, 336 MCContext &Ctx); 337 338 /// @} 339 /// \name Accessors 340 /// @{ 341 getSymbol()342 const MCSymbol &getSymbol() const { return *Symbol; } 343 getKind()344 VariantKind getKind() const { return Kind; } 345 346 void printVariantKind(raw_ostream &OS) const; 347 hasSubsectionsViaSymbols()348 bool hasSubsectionsViaSymbols() const { return HasSubsectionsViaSymbols; } 349 350 /// @} 351 /// \name Static Utility Functions 352 /// @{ 353 354 static StringRef getVariantKindName(VariantKind Kind); 355 356 static VariantKind getVariantKindForName(StringRef Name); 357 358 /// @} 359 classof(const MCExpr * E)360 static bool classof(const MCExpr *E) { 361 return E->getKind() == MCExpr::SymbolRef; 362 } 363 }; 364 365 /// Unary assembler expressions. 366 class MCUnaryExpr : public MCExpr { 367 public: 368 enum Opcode { 369 LNot, ///< Logical negation. 370 Minus, ///< Unary minus. 371 Not, ///< Bitwise negation. 372 Plus ///< Unary plus. 373 }; 374 375 private: 376 Opcode Op; 377 const MCExpr *Expr; 378 MCUnaryExpr(Opcode Op,const MCExpr * Expr,SMLoc Loc)379 MCUnaryExpr(Opcode Op, const MCExpr *Expr, SMLoc Loc) 380 : MCExpr(MCExpr::Unary, Loc), Op(Op), Expr(Expr) {} 381 382 public: 383 /// \name Construction 384 /// @{ 385 386 static const MCUnaryExpr *create(Opcode Op, const MCExpr *Expr, 387 MCContext &Ctx, SMLoc Loc = SMLoc()); 388 389 static const MCUnaryExpr *createLNot(const MCExpr *Expr, MCContext &Ctx, SMLoc Loc = SMLoc()) { 390 return create(LNot, Expr, Ctx, Loc); 391 } 392 393 static const MCUnaryExpr *createMinus(const MCExpr *Expr, MCContext &Ctx, SMLoc Loc = SMLoc()) { 394 return create(Minus, Expr, Ctx, Loc); 395 } 396 397 static const MCUnaryExpr *createNot(const MCExpr *Expr, MCContext &Ctx, SMLoc Loc = SMLoc()) { 398 return create(Not, Expr, Ctx, Loc); 399 } 400 401 static const MCUnaryExpr *createPlus(const MCExpr *Expr, MCContext &Ctx, SMLoc Loc = SMLoc()) { 402 return create(Plus, Expr, Ctx, Loc); 403 } 404 405 /// @} 406 /// \name Accessors 407 /// @{ 408 409 /// Get the kind of this unary expression. getOpcode()410 Opcode getOpcode() const { return Op; } 411 412 /// Get the child of this unary expression. getSubExpr()413 const MCExpr *getSubExpr() const { return Expr; } 414 415 /// @} 416 classof(const MCExpr * E)417 static bool classof(const MCExpr *E) { 418 return E->getKind() == MCExpr::Unary; 419 } 420 }; 421 422 /// Binary assembler expressions. 423 class MCBinaryExpr : public MCExpr { 424 public: 425 enum Opcode { 426 Add, ///< Addition. 427 And, ///< Bitwise and. 428 Div, ///< Signed division. 429 EQ, ///< Equality comparison. 430 GT, ///< Signed greater than comparison (result is either 0 or some 431 ///< target-specific non-zero value) 432 GTE, ///< Signed greater than or equal comparison (result is either 0 or 433 ///< some target-specific non-zero value). 434 LAnd, ///< Logical and. 435 LOr, ///< Logical or. 436 LT, ///< Signed less than comparison (result is either 0 or 437 ///< some target-specific non-zero value). 438 LTE, ///< Signed less than or equal comparison (result is either 0 or 439 ///< some target-specific non-zero value). 440 Mod, ///< Signed remainder. 441 Mul, ///< Multiplication. 442 NE, ///< Inequality comparison. 443 Or, ///< Bitwise or. 444 Shl, ///< Shift left. 445 AShr, ///< Arithmetic shift right. 446 LShr, ///< Logical shift right. 447 Sub, ///< Subtraction. 448 Xor ///< Bitwise exclusive or. 449 }; 450 451 private: 452 Opcode Op; 453 const MCExpr *LHS, *RHS; 454 455 MCBinaryExpr(Opcode Op, const MCExpr *LHS, const MCExpr *RHS, 456 SMLoc Loc = SMLoc()) MCExpr(MCExpr::Binary,Loc)457 : MCExpr(MCExpr::Binary, Loc), Op(Op), LHS(LHS), RHS(RHS) {} 458 459 public: 460 /// \name Construction 461 /// @{ 462 463 static const MCBinaryExpr *create(Opcode Op, const MCExpr *LHS, 464 const MCExpr *RHS, MCContext &Ctx, 465 SMLoc Loc = SMLoc()); 466 createAdd(const MCExpr * LHS,const MCExpr * RHS,MCContext & Ctx)467 static const MCBinaryExpr *createAdd(const MCExpr *LHS, const MCExpr *RHS, 468 MCContext &Ctx) { 469 return create(Add, LHS, RHS, Ctx); 470 } 471 createAnd(const MCExpr * LHS,const MCExpr * RHS,MCContext & Ctx)472 static const MCBinaryExpr *createAnd(const MCExpr *LHS, const MCExpr *RHS, 473 MCContext &Ctx) { 474 return create(And, LHS, RHS, Ctx); 475 } 476 createDiv(const MCExpr * LHS,const MCExpr * RHS,MCContext & Ctx)477 static const MCBinaryExpr *createDiv(const MCExpr *LHS, const MCExpr *RHS, 478 MCContext &Ctx) { 479 return create(Div, LHS, RHS, Ctx); 480 } 481 createEQ(const MCExpr * LHS,const MCExpr * RHS,MCContext & Ctx)482 static const MCBinaryExpr *createEQ(const MCExpr *LHS, const MCExpr *RHS, 483 MCContext &Ctx) { 484 return create(EQ, LHS, RHS, Ctx); 485 } 486 createGT(const MCExpr * LHS,const MCExpr * RHS,MCContext & Ctx)487 static const MCBinaryExpr *createGT(const MCExpr *LHS, const MCExpr *RHS, 488 MCContext &Ctx) { 489 return create(GT, LHS, RHS, Ctx); 490 } 491 createGTE(const MCExpr * LHS,const MCExpr * RHS,MCContext & Ctx)492 static const MCBinaryExpr *createGTE(const MCExpr *LHS, const MCExpr *RHS, 493 MCContext &Ctx) { 494 return create(GTE, LHS, RHS, Ctx); 495 } 496 createLAnd(const MCExpr * LHS,const MCExpr * RHS,MCContext & Ctx)497 static const MCBinaryExpr *createLAnd(const MCExpr *LHS, const MCExpr *RHS, 498 MCContext &Ctx) { 499 return create(LAnd, LHS, RHS, Ctx); 500 } 501 createLOr(const MCExpr * LHS,const MCExpr * RHS,MCContext & Ctx)502 static const MCBinaryExpr *createLOr(const MCExpr *LHS, const MCExpr *RHS, 503 MCContext &Ctx) { 504 return create(LOr, LHS, RHS, Ctx); 505 } 506 createLT(const MCExpr * LHS,const MCExpr * RHS,MCContext & Ctx)507 static const MCBinaryExpr *createLT(const MCExpr *LHS, const MCExpr *RHS, 508 MCContext &Ctx) { 509 return create(LT, LHS, RHS, Ctx); 510 } 511 createLTE(const MCExpr * LHS,const MCExpr * RHS,MCContext & Ctx)512 static const MCBinaryExpr *createLTE(const MCExpr *LHS, const MCExpr *RHS, 513 MCContext &Ctx) { 514 return create(LTE, LHS, RHS, Ctx); 515 } 516 createMod(const MCExpr * LHS,const MCExpr * RHS,MCContext & Ctx)517 static const MCBinaryExpr *createMod(const MCExpr *LHS, const MCExpr *RHS, 518 MCContext &Ctx) { 519 return create(Mod, LHS, RHS, Ctx); 520 } 521 createMul(const MCExpr * LHS,const MCExpr * RHS,MCContext & Ctx)522 static const MCBinaryExpr *createMul(const MCExpr *LHS, const MCExpr *RHS, 523 MCContext &Ctx) { 524 return create(Mul, LHS, RHS, Ctx); 525 } 526 createNE(const MCExpr * LHS,const MCExpr * RHS,MCContext & Ctx)527 static const MCBinaryExpr *createNE(const MCExpr *LHS, const MCExpr *RHS, 528 MCContext &Ctx) { 529 return create(NE, LHS, RHS, Ctx); 530 } 531 createOr(const MCExpr * LHS,const MCExpr * RHS,MCContext & Ctx)532 static const MCBinaryExpr *createOr(const MCExpr *LHS, const MCExpr *RHS, 533 MCContext &Ctx) { 534 return create(Or, LHS, RHS, Ctx); 535 } 536 createShl(const MCExpr * LHS,const MCExpr * RHS,MCContext & Ctx)537 static const MCBinaryExpr *createShl(const MCExpr *LHS, const MCExpr *RHS, 538 MCContext &Ctx) { 539 return create(Shl, LHS, RHS, Ctx); 540 } 541 createAShr(const MCExpr * LHS,const MCExpr * RHS,MCContext & Ctx)542 static const MCBinaryExpr *createAShr(const MCExpr *LHS, const MCExpr *RHS, 543 MCContext &Ctx) { 544 return create(AShr, LHS, RHS, Ctx); 545 } 546 createLShr(const MCExpr * LHS,const MCExpr * RHS,MCContext & Ctx)547 static const MCBinaryExpr *createLShr(const MCExpr *LHS, const MCExpr *RHS, 548 MCContext &Ctx) { 549 return create(LShr, LHS, RHS, Ctx); 550 } 551 createSub(const MCExpr * LHS,const MCExpr * RHS,MCContext & Ctx)552 static const MCBinaryExpr *createSub(const MCExpr *LHS, const MCExpr *RHS, 553 MCContext &Ctx) { 554 return create(Sub, LHS, RHS, Ctx); 555 } 556 createXor(const MCExpr * LHS,const MCExpr * RHS,MCContext & Ctx)557 static const MCBinaryExpr *createXor(const MCExpr *LHS, const MCExpr *RHS, 558 MCContext &Ctx) { 559 return create(Xor, LHS, RHS, Ctx); 560 } 561 562 /// @} 563 /// \name Accessors 564 /// @{ 565 566 /// Get the kind of this binary expression. getOpcode()567 Opcode getOpcode() const { return Op; } 568 569 /// Get the left-hand side expression of the binary operator. getLHS()570 const MCExpr *getLHS() const { return LHS; } 571 572 /// Get the right-hand side expression of the binary operator. getRHS()573 const MCExpr *getRHS() const { return RHS; } 574 575 /// @} 576 classof(const MCExpr * E)577 static bool classof(const MCExpr *E) { 578 return E->getKind() == MCExpr::Binary; 579 } 580 }; 581 582 /// This is an extension point for target-specific MCExpr subclasses to 583 /// implement. 584 /// 585 /// NOTE: All subclasses are required to have trivial destructors because 586 /// MCExprs are bump pointer allocated and not destructed. 587 class MCTargetExpr : public MCExpr { 588 virtual void anchor(); 589 590 protected: MCTargetExpr()591 MCTargetExpr() : MCExpr(Target, SMLoc()) {} 592 virtual ~MCTargetExpr() = default; 593 594 public: 595 virtual void printImpl(raw_ostream &OS, const MCAsmInfo *MAI) const = 0; 596 virtual bool evaluateAsRelocatableImpl(MCValue &Res, 597 const MCAsmLayout *Layout, 598 const MCFixup *Fixup) const = 0; 599 // allow Target Expressions to be checked for equality isEqualTo(const MCExpr * x)600 virtual bool isEqualTo(const MCExpr *x) const { return false; } 601 // This should be set when assigned expressions are not valid ".set" 602 // expressions, e.g. registers, and must be inlined. inlineAssignedExpr()603 virtual bool inlineAssignedExpr() const { return false; } 604 virtual void visitUsedExpr(MCStreamer& Streamer) const = 0; 605 virtual MCFragment *findAssociatedFragment() const = 0; 606 607 virtual void fixELFSymbolsInTLSFixups(MCAssembler &) const = 0; 608 classof(const MCExpr * E)609 static bool classof(const MCExpr *E) { 610 return E->getKind() == MCExpr::Target; 611 } 612 }; 613 614 } // end namespace llvm 615 616 #endif // LLVM_MC_MCEXPR_H 617