1 //===- MCExpr.cpp - Assembly Level Expression Implementation --------------===// 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 #include "llvm/MC/MCExpr.h" 10 #include "llvm/ADT/Statistic.h" 11 #include "llvm/ADT/StringSwitch.h" 12 #include "llvm/Config/llvm-config.h" 13 #include "llvm/MC/MCAsmBackend.h" 14 #include "llvm/MC/MCAsmInfo.h" 15 #include "llvm/MC/MCAssembler.h" 16 #include "llvm/MC/MCContext.h" 17 #include "llvm/MC/MCObjectWriter.h" 18 #include "llvm/MC/MCSymbol.h" 19 #include "llvm/MC/MCValue.h" 20 #include "llvm/Support/Casting.h" 21 #include "llvm/Support/Compiler.h" 22 #include "llvm/Support/Debug.h" 23 #include "llvm/Support/ErrorHandling.h" 24 #include "llvm/Support/raw_ostream.h" 25 #include <cassert> 26 #include <cstdint> 27 28 using namespace llvm; 29 30 #define DEBUG_TYPE "mcexpr" 31 32 namespace { 33 namespace stats { 34 35 STATISTIC(MCExprEvaluate, "Number of MCExpr evaluations"); 36 37 } // end namespace stats 38 } // end anonymous namespace 39 40 void MCExpr::print(raw_ostream &OS, const MCAsmInfo *MAI, bool InParens) const { 41 switch (getKind()) { 42 case MCExpr::Target: 43 return cast<MCTargetExpr>(this)->printImpl(OS, MAI); 44 case MCExpr::Constant: { 45 auto Value = cast<MCConstantExpr>(*this).getValue(); 46 auto PrintInHex = cast<MCConstantExpr>(*this).useHexFormat(); 47 auto SizeInBytes = cast<MCConstantExpr>(*this).getSizeInBytes(); 48 if (Value < 0 && MAI && !MAI->supportsSignedData()) 49 PrintInHex = true; 50 if (PrintInHex) 51 switch (SizeInBytes) { 52 default: 53 OS << "0x" << Twine::utohexstr(Value); 54 break; 55 case 1: 56 OS << format("0x%02" PRIx64, Value); 57 break; 58 case 2: 59 OS << format("0x%04" PRIx64, Value); 60 break; 61 case 4: 62 OS << format("0x%08" PRIx64, Value); 63 break; 64 case 8: 65 OS << format("0x%016" PRIx64, Value); 66 break; 67 } 68 else 69 OS << Value; 70 return; 71 } 72 case MCExpr::SymbolRef: { 73 const MCSymbolRefExpr &SRE = cast<MCSymbolRefExpr>(*this); 74 const MCSymbol &Sym = SRE.getSymbol(); 75 // Parenthesize names that start with $ so that they don't look like 76 // absolute names. 77 bool UseParens = MAI && MAI->useParensForDollarSignNames() && !InParens && 78 Sym.getName().starts_with('$'); 79 80 if (UseParens) { 81 OS << '('; 82 Sym.print(OS, MAI); 83 OS << ')'; 84 } else 85 Sym.print(OS, MAI); 86 87 const MCSymbolRefExpr::VariantKind Kind = SRE.getKind(); 88 if (Kind != MCSymbolRefExpr::VK_None) { 89 if (MAI && MAI->useParensForSymbolVariant()) // ARM 90 OS << '(' << MCSymbolRefExpr::getVariantKindName(Kind) << ')'; 91 else 92 OS << '@' << MCSymbolRefExpr::getVariantKindName(Kind); 93 } 94 95 return; 96 } 97 98 case MCExpr::Unary: { 99 const MCUnaryExpr &UE = cast<MCUnaryExpr>(*this); 100 switch (UE.getOpcode()) { 101 case MCUnaryExpr::LNot: OS << '!'; break; 102 case MCUnaryExpr::Minus: OS << '-'; break; 103 case MCUnaryExpr::Not: OS << '~'; break; 104 case MCUnaryExpr::Plus: OS << '+'; break; 105 } 106 bool Binary = UE.getSubExpr()->getKind() == MCExpr::Binary; 107 if (Binary) OS << "("; 108 UE.getSubExpr()->print(OS, MAI); 109 if (Binary) OS << ")"; 110 return; 111 } 112 113 case MCExpr::Binary: { 114 const MCBinaryExpr &BE = cast<MCBinaryExpr>(*this); 115 116 // Only print parens around the LHS if it is non-trivial. 117 if (isa<MCConstantExpr>(BE.getLHS()) || isa<MCSymbolRefExpr>(BE.getLHS())) { 118 BE.getLHS()->print(OS, MAI); 119 } else { 120 OS << '('; 121 BE.getLHS()->print(OS, MAI); 122 OS << ')'; 123 } 124 125 switch (BE.getOpcode()) { 126 case MCBinaryExpr::Add: 127 // Print "X-42" instead of "X+-42". 128 if (const MCConstantExpr *RHSC = dyn_cast<MCConstantExpr>(BE.getRHS())) { 129 if (RHSC->getValue() < 0) { 130 OS << RHSC->getValue(); 131 return; 132 } 133 } 134 135 OS << '+'; 136 break; 137 case MCBinaryExpr::AShr: OS << ">>"; break; 138 case MCBinaryExpr::And: OS << '&'; break; 139 case MCBinaryExpr::Div: OS << '/'; break; 140 case MCBinaryExpr::EQ: OS << "=="; break; 141 case MCBinaryExpr::GT: OS << '>'; break; 142 case MCBinaryExpr::GTE: OS << ">="; break; 143 case MCBinaryExpr::LAnd: OS << "&&"; break; 144 case MCBinaryExpr::LOr: OS << "||"; break; 145 case MCBinaryExpr::LShr: OS << ">>"; break; 146 case MCBinaryExpr::LT: OS << '<'; break; 147 case MCBinaryExpr::LTE: OS << "<="; break; 148 case MCBinaryExpr::Mod: OS << '%'; break; 149 case MCBinaryExpr::Mul: OS << '*'; break; 150 case MCBinaryExpr::NE: OS << "!="; break; 151 case MCBinaryExpr::Or: OS << '|'; break; 152 case MCBinaryExpr::OrNot: OS << '!'; break; 153 case MCBinaryExpr::Shl: OS << "<<"; break; 154 case MCBinaryExpr::Sub: OS << '-'; break; 155 case MCBinaryExpr::Xor: OS << '^'; break; 156 } 157 158 // Only print parens around the LHS if it is non-trivial. 159 if (isa<MCConstantExpr>(BE.getRHS()) || isa<MCSymbolRefExpr>(BE.getRHS())) { 160 BE.getRHS()->print(OS, MAI); 161 } else { 162 OS << '('; 163 BE.getRHS()->print(OS, MAI); 164 OS << ')'; 165 } 166 return; 167 } 168 } 169 170 llvm_unreachable("Invalid expression kind!"); 171 } 172 173 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) 174 LLVM_DUMP_METHOD void MCExpr::dump() const { 175 dbgs() << *this; 176 dbgs() << '\n'; 177 } 178 #endif 179 180 bool MCExpr::isSymbolUsedInExpression(const MCSymbol *Sym) const { 181 switch (getKind()) { 182 case MCExpr::Binary: { 183 const MCBinaryExpr *BE = static_cast<const MCBinaryExpr *>(this); 184 return BE->getLHS()->isSymbolUsedInExpression(Sym) || 185 BE->getRHS()->isSymbolUsedInExpression(Sym); 186 } 187 case MCExpr::Target: { 188 const MCTargetExpr *TE = static_cast<const MCTargetExpr *>(this); 189 return TE->isSymbolUsedInExpression(Sym); 190 } 191 case MCExpr::Constant: 192 return false; 193 case MCExpr::SymbolRef: { 194 const MCSymbol &S = static_cast<const MCSymbolRefExpr *>(this)->getSymbol(); 195 if (S.isVariable() && !S.isWeakExternal()) 196 return S.getVariableValue()->isSymbolUsedInExpression(Sym); 197 return &S == Sym; 198 } 199 case MCExpr::Unary: { 200 const MCExpr *SubExpr = 201 static_cast<const MCUnaryExpr *>(this)->getSubExpr(); 202 return SubExpr->isSymbolUsedInExpression(Sym); 203 } 204 } 205 206 llvm_unreachable("Unknown expr kind!"); 207 } 208 209 /* *** */ 210 211 const MCBinaryExpr *MCBinaryExpr::create(Opcode Opc, const MCExpr *LHS, 212 const MCExpr *RHS, MCContext &Ctx, 213 SMLoc Loc) { 214 return new (Ctx) MCBinaryExpr(Opc, LHS, RHS, Loc); 215 } 216 217 const MCUnaryExpr *MCUnaryExpr::create(Opcode Opc, const MCExpr *Expr, 218 MCContext &Ctx, SMLoc Loc) { 219 return new (Ctx) MCUnaryExpr(Opc, Expr, Loc); 220 } 221 222 const MCConstantExpr *MCConstantExpr::create(int64_t Value, MCContext &Ctx, 223 bool PrintInHex, 224 unsigned SizeInBytes) { 225 return new (Ctx) MCConstantExpr(Value, PrintInHex, SizeInBytes); 226 } 227 228 /* *** */ 229 230 MCSymbolRefExpr::MCSymbolRefExpr(const MCSymbol *Symbol, VariantKind Kind, 231 const MCAsmInfo *MAI, SMLoc Loc) 232 : MCExpr(MCExpr::SymbolRef, Loc, 233 encodeSubclassData(Kind, MAI->hasSubsectionsViaSymbols())), 234 Symbol(Symbol) { 235 assert(Symbol); 236 } 237 238 const MCSymbolRefExpr *MCSymbolRefExpr::create(const MCSymbol *Sym, 239 VariantKind Kind, 240 MCContext &Ctx, SMLoc Loc) { 241 return new (Ctx) MCSymbolRefExpr(Sym, Kind, Ctx.getAsmInfo(), Loc); 242 } 243 244 const MCSymbolRefExpr *MCSymbolRefExpr::create(StringRef Name, VariantKind Kind, 245 MCContext &Ctx) { 246 return create(Ctx.getOrCreateSymbol(Name), Kind, Ctx); 247 } 248 249 StringRef MCSymbolRefExpr::getVariantKindName(VariantKind Kind) { 250 switch (Kind) { 251 // clang-format off 252 case VK_Invalid: return "<<invalid>>"; 253 case VK_None: return "<<none>>"; 254 255 case VK_DTPOFF: return "DTPOFF"; 256 case VK_DTPREL: return "DTPREL"; 257 case VK_GOT: return "GOT"; 258 case VK_GOTENT: return "GOTENT"; 259 case VK_GOTOFF: return "GOTOFF"; 260 case VK_GOTREL: return "GOTREL"; 261 case VK_PCREL: return "PCREL"; 262 case VK_GOTPCREL: return "GOTPCREL"; 263 case VK_GOTPCREL_NORELAX: return "GOTPCREL_NORELAX"; 264 case VK_GOTTPOFF: return "GOTTPOFF"; 265 case VK_GOTTPOFF_FDPIC: return "gottpoff_fdpic"; 266 case VK_INDNTPOFF: return "INDNTPOFF"; 267 case VK_NTPOFF: return "NTPOFF"; 268 case VK_GOTNTPOFF: return "GOTNTPOFF"; 269 case VK_PLT: return "PLT"; 270 case VK_TLSGD: return "TLSGD"; 271 case VK_TLSGD_FDPIC: return "tlsgd_fdpic"; 272 case VK_TLSLD: return "TLSLD"; 273 case VK_TLSLDM: return "TLSLDM"; 274 case VK_TLSLDM_FDPIC: return "tlsldm_fdpic"; 275 case VK_TPOFF: return "TPOFF"; 276 case VK_TPREL: return "TPREL"; 277 case VK_TLSCALL: return "tlscall"; 278 case VK_TLSDESC: return "tlsdesc"; 279 case VK_TLVP: return "TLVP"; 280 case VK_TLVPPAGE: return "TLVPPAGE"; 281 case VK_TLVPPAGEOFF: return "TLVPPAGEOFF"; 282 case VK_PAGE: return "PAGE"; 283 case VK_PAGEOFF: return "PAGEOFF"; 284 case VK_GOTPAGE: return "GOTPAGE"; 285 case VK_GOTPAGEOFF: return "GOTPAGEOFF"; 286 case VK_SECREL: return "SECREL32"; 287 case VK_SIZE: return "SIZE"; 288 case VK_WEAKREF: return "WEAKREF"; 289 case VK_FUNCDESC: return "FUNCDESC"; 290 case VK_GOTFUNCDESC: return "GOTFUNCDESC"; 291 case VK_GOTOFFFUNCDESC: return "GOTOFFFUNCDESC"; 292 case VK_X86_ABS8: return "ABS8"; 293 case VK_X86_PLTOFF: return "PLTOFF"; 294 case VK_ARM_NONE: return "none"; 295 case VK_ARM_GOT_PREL: return "GOT_PREL"; 296 case VK_ARM_TARGET1: return "target1"; 297 case VK_ARM_TARGET2: return "target2"; 298 case VK_ARM_PREL31: return "prel31"; 299 case VK_ARM_SBREL: return "sbrel"; 300 case VK_ARM_TLSLDO: return "tlsldo"; 301 case VK_ARM_TLSDESCSEQ: return "tlsdescseq"; 302 case VK_AVR_NONE: return "none"; 303 case VK_AVR_LO8: return "lo8"; 304 case VK_AVR_HI8: return "hi8"; 305 case VK_AVR_HLO8: return "hlo8"; 306 case VK_AVR_DIFF8: return "diff8"; 307 case VK_AVR_DIFF16: return "diff16"; 308 case VK_AVR_DIFF32: return "diff32"; 309 case VK_AVR_PM: return "pm"; 310 case VK_PPC_LO: return "l"; 311 case VK_PPC_HI: return "h"; 312 case VK_PPC_HA: return "ha"; 313 case VK_PPC_HIGH: return "high"; 314 case VK_PPC_HIGHA: return "higha"; 315 case VK_PPC_HIGHER: return "higher"; 316 case VK_PPC_HIGHERA: return "highera"; 317 case VK_PPC_HIGHEST: return "highest"; 318 case VK_PPC_HIGHESTA: return "highesta"; 319 case VK_PPC_GOT_LO: return "got@l"; 320 case VK_PPC_GOT_HI: return "got@h"; 321 case VK_PPC_GOT_HA: return "got@ha"; 322 case VK_PPC_TOCBASE: return "tocbase"; 323 case VK_PPC_TOC: return "toc"; 324 case VK_PPC_TOC_LO: return "toc@l"; 325 case VK_PPC_TOC_HI: return "toc@h"; 326 case VK_PPC_TOC_HA: return "toc@ha"; 327 case VK_PPC_U: return "u"; 328 case VK_PPC_L: return "l"; 329 case VK_PPC_DTPMOD: return "dtpmod"; 330 case VK_PPC_TPREL_LO: return "tprel@l"; 331 case VK_PPC_TPREL_HI: return "tprel@h"; 332 case VK_PPC_TPREL_HA: return "tprel@ha"; 333 case VK_PPC_TPREL_HIGH: return "tprel@high"; 334 case VK_PPC_TPREL_HIGHA: return "tprel@higha"; 335 case VK_PPC_TPREL_HIGHER: return "tprel@higher"; 336 case VK_PPC_TPREL_HIGHERA: return "tprel@highera"; 337 case VK_PPC_TPREL_HIGHEST: return "tprel@highest"; 338 case VK_PPC_TPREL_HIGHESTA: return "tprel@highesta"; 339 case VK_PPC_DTPREL_LO: return "dtprel@l"; 340 case VK_PPC_DTPREL_HI: return "dtprel@h"; 341 case VK_PPC_DTPREL_HA: return "dtprel@ha"; 342 case VK_PPC_DTPREL_HIGH: return "dtprel@high"; 343 case VK_PPC_DTPREL_HIGHA: return "dtprel@higha"; 344 case VK_PPC_DTPREL_HIGHER: return "dtprel@higher"; 345 case VK_PPC_DTPREL_HIGHERA: return "dtprel@highera"; 346 case VK_PPC_DTPREL_HIGHEST: return "dtprel@highest"; 347 case VK_PPC_DTPREL_HIGHESTA: return "dtprel@highesta"; 348 case VK_PPC_GOT_TPREL: return "got@tprel"; 349 case VK_PPC_GOT_TPREL_LO: return "got@tprel@l"; 350 case VK_PPC_GOT_TPREL_HI: return "got@tprel@h"; 351 case VK_PPC_GOT_TPREL_HA: return "got@tprel@ha"; 352 case VK_PPC_GOT_DTPREL: return "got@dtprel"; 353 case VK_PPC_GOT_DTPREL_LO: return "got@dtprel@l"; 354 case VK_PPC_GOT_DTPREL_HI: return "got@dtprel@h"; 355 case VK_PPC_GOT_DTPREL_HA: return "got@dtprel@ha"; 356 case VK_PPC_TLS: return "tls"; 357 case VK_PPC_GOT_TLSGD: return "got@tlsgd"; 358 case VK_PPC_GOT_TLSGD_LO: return "got@tlsgd@l"; 359 case VK_PPC_GOT_TLSGD_HI: return "got@tlsgd@h"; 360 case VK_PPC_GOT_TLSGD_HA: return "got@tlsgd@ha"; 361 case VK_PPC_TLSGD: return "tlsgd"; 362 case VK_PPC_AIX_TLSGD: 363 return "gd"; 364 case VK_PPC_AIX_TLSGDM: 365 return "m"; 366 case VK_PPC_AIX_TLSIE: 367 return "ie"; 368 case VK_PPC_AIX_TLSLE: 369 return "le"; 370 case VK_PPC_AIX_TLSLD: 371 return "ld"; 372 case VK_PPC_AIX_TLSML: 373 return "ml"; 374 case VK_PPC_GOT_TLSLD: return "got@tlsld"; 375 case VK_PPC_GOT_TLSLD_LO: return "got@tlsld@l"; 376 case VK_PPC_GOT_TLSLD_HI: return "got@tlsld@h"; 377 case VK_PPC_GOT_TLSLD_HA: return "got@tlsld@ha"; 378 case VK_PPC_GOT_PCREL: 379 return "got@pcrel"; 380 case VK_PPC_GOT_TLSGD_PCREL: 381 return "got@tlsgd@pcrel"; 382 case VK_PPC_GOT_TLSLD_PCREL: 383 return "got@tlsld@pcrel"; 384 case VK_PPC_GOT_TPREL_PCREL: 385 return "got@tprel@pcrel"; 386 case VK_PPC_TLS_PCREL: 387 return "tls@pcrel"; 388 case VK_PPC_TLSLD: return "tlsld"; 389 case VK_PPC_LOCAL: return "local"; 390 case VK_PPC_NOTOC: return "notoc"; 391 case VK_PPC_PCREL_OPT: return "<<invalid>>"; 392 case VK_COFF_IMGREL32: return "IMGREL"; 393 case VK_Hexagon_LO16: return "LO16"; 394 case VK_Hexagon_HI16: return "HI16"; 395 case VK_Hexagon_GPREL: return "GPREL"; 396 case VK_Hexagon_GD_GOT: return "GDGOT"; 397 case VK_Hexagon_LD_GOT: return "LDGOT"; 398 case VK_Hexagon_GD_PLT: return "GDPLT"; 399 case VK_Hexagon_LD_PLT: return "LDPLT"; 400 case VK_Hexagon_IE: return "IE"; 401 case VK_Hexagon_IE_GOT: return "IEGOT"; 402 case VK_WASM_TYPEINDEX: return "TYPEINDEX"; 403 case VK_WASM_MBREL: return "MBREL"; 404 case VK_WASM_TLSREL: return "TLSREL"; 405 case VK_WASM_TBREL: return "TBREL"; 406 case VK_WASM_GOT_TLS: return "GOT@TLS"; 407 case VK_WASM_FUNCINDEX: return "FUNCINDEX"; 408 case VK_AMDGPU_GOTPCREL32_LO: return "gotpcrel32@lo"; 409 case VK_AMDGPU_GOTPCREL32_HI: return "gotpcrel32@hi"; 410 case VK_AMDGPU_REL32_LO: return "rel32@lo"; 411 case VK_AMDGPU_REL32_HI: return "rel32@hi"; 412 case VK_AMDGPU_REL64: return "rel64"; 413 case VK_AMDGPU_ABS32_LO: return "abs32@lo"; 414 case VK_AMDGPU_ABS32_HI: return "abs32@hi"; 415 case VK_VE_HI32: return "hi"; 416 case VK_VE_LO32: return "lo"; 417 case VK_VE_PC_HI32: return "pc_hi"; 418 case VK_VE_PC_LO32: return "pc_lo"; 419 case VK_VE_GOT_HI32: return "got_hi"; 420 case VK_VE_GOT_LO32: return "got_lo"; 421 case VK_VE_GOTOFF_HI32: return "gotoff_hi"; 422 case VK_VE_GOTOFF_LO32: return "gotoff_lo"; 423 case VK_VE_PLT_HI32: return "plt_hi"; 424 case VK_VE_PLT_LO32: return "plt_lo"; 425 case VK_VE_TLS_GD_HI32: return "tls_gd_hi"; 426 case VK_VE_TLS_GD_LO32: return "tls_gd_lo"; 427 case VK_VE_TPOFF_HI32: return "tpoff_hi"; 428 case VK_VE_TPOFF_LO32: return "tpoff_lo"; 429 // clang-format on 430 } 431 llvm_unreachable("Invalid variant kind"); 432 } 433 434 MCSymbolRefExpr::VariantKind 435 MCSymbolRefExpr::getVariantKindForName(StringRef Name) { 436 return StringSwitch<VariantKind>(Name.lower()) 437 .Case("dtprel", VK_DTPREL) 438 .Case("dtpoff", VK_DTPOFF) 439 .Case("got", VK_GOT) 440 .Case("gotent", VK_GOTENT) 441 .Case("gotoff", VK_GOTOFF) 442 .Case("gotrel", VK_GOTREL) 443 .Case("pcrel", VK_PCREL) 444 .Case("gotpcrel", VK_GOTPCREL) 445 .Case("gotpcrel_norelax", VK_GOTPCREL_NORELAX) 446 .Case("gottpoff", VK_GOTTPOFF) 447 .Case("indntpoff", VK_INDNTPOFF) 448 .Case("ntpoff", VK_NTPOFF) 449 .Case("gotntpoff", VK_GOTNTPOFF) 450 .Case("plt", VK_PLT) 451 .Case("tlscall", VK_TLSCALL) 452 .Case("tlsdesc", VK_TLSDESC) 453 .Case("tlsgd", VK_TLSGD) 454 .Case("tlsld", VK_TLSLD) 455 .Case("tlsldm", VK_TLSLDM) 456 .Case("tpoff", VK_TPOFF) 457 .Case("tprel", VK_TPREL) 458 .Case("tlvp", VK_TLVP) 459 .Case("tlvppage", VK_TLVPPAGE) 460 .Case("tlvppageoff", VK_TLVPPAGEOFF) 461 .Case("page", VK_PAGE) 462 .Case("pageoff", VK_PAGEOFF) 463 .Case("gotpage", VK_GOTPAGE) 464 .Case("gotpageoff", VK_GOTPAGEOFF) 465 .Case("imgrel", VK_COFF_IMGREL32) 466 .Case("secrel32", VK_SECREL) 467 .Case("size", VK_SIZE) 468 .Case("abs8", VK_X86_ABS8) 469 .Case("pltoff", VK_X86_PLTOFF) 470 .Case("l", VK_PPC_LO) 471 .Case("h", VK_PPC_HI) 472 .Case("ha", VK_PPC_HA) 473 .Case("high", VK_PPC_HIGH) 474 .Case("higha", VK_PPC_HIGHA) 475 .Case("higher", VK_PPC_HIGHER) 476 .Case("highera", VK_PPC_HIGHERA) 477 .Case("highest", VK_PPC_HIGHEST) 478 .Case("highesta", VK_PPC_HIGHESTA) 479 .Case("got@l", VK_PPC_GOT_LO) 480 .Case("got@h", VK_PPC_GOT_HI) 481 .Case("got@ha", VK_PPC_GOT_HA) 482 .Case("local", VK_PPC_LOCAL) 483 .Case("tocbase", VK_PPC_TOCBASE) 484 .Case("toc", VK_PPC_TOC) 485 .Case("toc@l", VK_PPC_TOC_LO) 486 .Case("toc@h", VK_PPC_TOC_HI) 487 .Case("toc@ha", VK_PPC_TOC_HA) 488 .Case("u", VK_PPC_U) 489 .Case("l", VK_PPC_L) 490 .Case("tls", VK_PPC_TLS) 491 .Case("dtpmod", VK_PPC_DTPMOD) 492 .Case("tprel@l", VK_PPC_TPREL_LO) 493 .Case("tprel@h", VK_PPC_TPREL_HI) 494 .Case("tprel@ha", VK_PPC_TPREL_HA) 495 .Case("tprel@high", VK_PPC_TPREL_HIGH) 496 .Case("tprel@higha", VK_PPC_TPREL_HIGHA) 497 .Case("tprel@higher", VK_PPC_TPREL_HIGHER) 498 .Case("tprel@highera", VK_PPC_TPREL_HIGHERA) 499 .Case("tprel@highest", VK_PPC_TPREL_HIGHEST) 500 .Case("tprel@highesta", VK_PPC_TPREL_HIGHESTA) 501 .Case("dtprel@l", VK_PPC_DTPREL_LO) 502 .Case("dtprel@h", VK_PPC_DTPREL_HI) 503 .Case("dtprel@ha", VK_PPC_DTPREL_HA) 504 .Case("dtprel@high", VK_PPC_DTPREL_HIGH) 505 .Case("dtprel@higha", VK_PPC_DTPREL_HIGHA) 506 .Case("dtprel@higher", VK_PPC_DTPREL_HIGHER) 507 .Case("dtprel@highera", VK_PPC_DTPREL_HIGHERA) 508 .Case("dtprel@highest", VK_PPC_DTPREL_HIGHEST) 509 .Case("dtprel@highesta", VK_PPC_DTPREL_HIGHESTA) 510 .Case("got@tprel", VK_PPC_GOT_TPREL) 511 .Case("got@tprel@l", VK_PPC_GOT_TPREL_LO) 512 .Case("got@tprel@h", VK_PPC_GOT_TPREL_HI) 513 .Case("got@tprel@ha", VK_PPC_GOT_TPREL_HA) 514 .Case("got@dtprel", VK_PPC_GOT_DTPREL) 515 .Case("got@dtprel@l", VK_PPC_GOT_DTPREL_LO) 516 .Case("got@dtprel@h", VK_PPC_GOT_DTPREL_HI) 517 .Case("got@dtprel@ha", VK_PPC_GOT_DTPREL_HA) 518 .Case("got@tlsgd", VK_PPC_GOT_TLSGD) 519 .Case("got@tlsgd@l", VK_PPC_GOT_TLSGD_LO) 520 .Case("got@tlsgd@h", VK_PPC_GOT_TLSGD_HI) 521 .Case("got@tlsgd@ha", VK_PPC_GOT_TLSGD_HA) 522 .Case("got@tlsld", VK_PPC_GOT_TLSLD) 523 .Case("got@tlsld@l", VK_PPC_GOT_TLSLD_LO) 524 .Case("got@tlsld@h", VK_PPC_GOT_TLSLD_HI) 525 .Case("got@tlsld@ha", VK_PPC_GOT_TLSLD_HA) 526 .Case("got@pcrel", VK_PPC_GOT_PCREL) 527 .Case("got@tlsgd@pcrel", VK_PPC_GOT_TLSGD_PCREL) 528 .Case("got@tlsld@pcrel", VK_PPC_GOT_TLSLD_PCREL) 529 .Case("got@tprel@pcrel", VK_PPC_GOT_TPREL_PCREL) 530 .Case("tls@pcrel", VK_PPC_TLS_PCREL) 531 .Case("notoc", VK_PPC_NOTOC) 532 .Case("gdgot", VK_Hexagon_GD_GOT) 533 .Case("gdplt", VK_Hexagon_GD_PLT) 534 .Case("iegot", VK_Hexagon_IE_GOT) 535 .Case("ie", VK_Hexagon_IE) 536 .Case("ldgot", VK_Hexagon_LD_GOT) 537 .Case("ldplt", VK_Hexagon_LD_PLT) 538 .Case("lo8", VK_AVR_LO8) 539 .Case("hi8", VK_AVR_HI8) 540 .Case("hlo8", VK_AVR_HLO8) 541 .Case("typeindex", VK_WASM_TYPEINDEX) 542 .Case("tbrel", VK_WASM_TBREL) 543 .Case("mbrel", VK_WASM_MBREL) 544 .Case("tlsrel", VK_WASM_TLSREL) 545 .Case("got@tls", VK_WASM_GOT_TLS) 546 .Case("funcindex", VK_WASM_FUNCINDEX) 547 .Case("gotpcrel32@lo", VK_AMDGPU_GOTPCREL32_LO) 548 .Case("gotpcrel32@hi", VK_AMDGPU_GOTPCREL32_HI) 549 .Case("rel32@lo", VK_AMDGPU_REL32_LO) 550 .Case("rel32@hi", VK_AMDGPU_REL32_HI) 551 .Case("rel64", VK_AMDGPU_REL64) 552 .Case("abs32@lo", VK_AMDGPU_ABS32_LO) 553 .Case("abs32@hi", VK_AMDGPU_ABS32_HI) 554 .Case("hi", VK_VE_HI32) 555 .Case("lo", VK_VE_LO32) 556 .Case("pc_hi", VK_VE_PC_HI32) 557 .Case("pc_lo", VK_VE_PC_LO32) 558 .Case("got_hi", VK_VE_GOT_HI32) 559 .Case("got_lo", VK_VE_GOT_LO32) 560 .Case("gotoff_hi", VK_VE_GOTOFF_HI32) 561 .Case("gotoff_lo", VK_VE_GOTOFF_LO32) 562 .Case("plt_hi", VK_VE_PLT_HI32) 563 .Case("plt_lo", VK_VE_PLT_LO32) 564 .Case("tls_gd_hi", VK_VE_TLS_GD_HI32) 565 .Case("tls_gd_lo", VK_VE_TLS_GD_LO32) 566 .Case("tpoff_hi", VK_VE_TPOFF_HI32) 567 .Case("tpoff_lo", VK_VE_TPOFF_LO32) 568 .Default(VK_Invalid); 569 } 570 571 /* *** */ 572 573 void MCTargetExpr::anchor() {} 574 575 /* *** */ 576 577 bool MCExpr::evaluateAsAbsolute(int64_t &Res) const { 578 return evaluateAsAbsolute(Res, nullptr, nullptr, false); 579 } 580 581 bool MCExpr::evaluateAsAbsolute(int64_t &Res, const MCAssembler &Asm, 582 const SectionAddrMap &Addrs) const { 583 // Setting InSet causes us to absolutize differences across sections and that 584 // is what the MachO writer uses Addrs for. 585 return evaluateAsAbsolute(Res, &Asm, &Addrs, true); 586 } 587 588 bool MCExpr::evaluateAsAbsolute(int64_t &Res, const MCAssembler &Asm) const { 589 return evaluateAsAbsolute(Res, &Asm, nullptr, false); 590 } 591 592 bool MCExpr::evaluateAsAbsolute(int64_t &Res, const MCAssembler *Asm) const { 593 return evaluateAsAbsolute(Res, Asm, nullptr, false); 594 } 595 596 bool MCExpr::evaluateKnownAbsolute(int64_t &Res, const MCAssembler &Asm) const { 597 return evaluateAsAbsolute(Res, &Asm, nullptr, true); 598 } 599 600 bool MCExpr::evaluateAsAbsolute(int64_t &Res, const MCAssembler *Asm, 601 const SectionAddrMap *Addrs, bool InSet) const { 602 MCValue Value; 603 604 // Fast path constants. 605 if (const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(this)) { 606 Res = CE->getValue(); 607 return true; 608 } 609 610 bool IsRelocatable = 611 evaluateAsRelocatableImpl(Value, Asm, nullptr, Addrs, InSet); 612 613 // Record the current value. 614 Res = Value.getConstant(); 615 616 return IsRelocatable && Value.isAbsolute(); 617 } 618 619 /// Helper method for \see EvaluateSymbolAdd(). 620 static void AttemptToFoldSymbolOffsetDifference( 621 const MCAssembler *Asm, const SectionAddrMap *Addrs, bool InSet, 622 const MCSymbolRefExpr *&A, const MCSymbolRefExpr *&B, int64_t &Addend) { 623 if (!A || !B) 624 return; 625 626 const MCSymbol &SA = A->getSymbol(); 627 const MCSymbol &SB = B->getSymbol(); 628 629 if (SA.isUndefined() || SB.isUndefined()) 630 return; 631 632 if (!Asm->getWriter().isSymbolRefDifferenceFullyResolved(*Asm, A, B, InSet)) 633 return; 634 635 auto FinalizeFolding = [&]() { 636 // Pointers to Thumb symbols need to have their low-bit set to allow 637 // for interworking. 638 if (Asm->isThumbFunc(&SA)) 639 Addend |= 1; 640 641 // Clear the symbol expr pointers to indicate we have folded these 642 // operands. 643 A = B = nullptr; 644 }; 645 646 const MCFragment *FA = SA.getFragment(); 647 const MCFragment *FB = SB.getFragment(); 648 const MCSection &SecA = *FA->getParent(); 649 const MCSection &SecB = *FB->getParent(); 650 if ((&SecA != &SecB) && !Addrs) 651 return; 652 653 // When layout is available, we can generally compute the difference using the 654 // getSymbolOffset path, which also avoids the possible slow fragment walk. 655 // However, linker relaxation may cause incorrect fold of A-B if A and B are 656 // separated by a linker-relaxable instruction. If the section contains 657 // instructions and InSet is false (not expressions in directive like 658 // .size/.fill), disable the fast path. 659 bool Layout = Asm->hasLayout(); 660 if (Layout && (InSet || !SecA.hasInstructions() || 661 !Asm->getBackend().allowLinkerRelaxation())) { 662 // If both symbols are in the same fragment, return the difference of their 663 // offsets. canGetFragmentOffset(FA) may be false. 664 if (FA == FB && !SA.isVariable() && !SB.isVariable()) { 665 Addend += SA.getOffset() - SB.getOffset(); 666 return FinalizeFolding(); 667 } 668 669 // Eagerly evaluate when layout is finalized. 670 Addend += Asm->getSymbolOffset(A->getSymbol()) - 671 Asm->getSymbolOffset(B->getSymbol()); 672 if (Addrs && (&SecA != &SecB)) 673 Addend += (Addrs->lookup(&SecA) - Addrs->lookup(&SecB)); 674 675 FinalizeFolding(); 676 } else { 677 // When layout is not finalized, our ability to resolve differences between 678 // symbols is limited to specific cases where the fragments between two 679 // symbols (including the fragments the symbols are defined in) are 680 // fixed-size fragments so the difference can be calculated. For example, 681 // this is important when the Subtarget is changed and a new MCDataFragment 682 // is created in the case of foo: instr; .arch_extension ext; instr .if . - 683 // foo. 684 if (SA.isVariable() || SB.isVariable()) 685 return; 686 687 // Try to find a constant displacement from FA to FB, add the displacement 688 // between the offset in FA of SA and the offset in FB of SB. 689 bool Reverse = false; 690 if (FA == FB) 691 Reverse = SA.getOffset() < SB.getOffset(); 692 else 693 Reverse = FA->getLayoutOrder() < FB->getLayoutOrder(); 694 695 uint64_t SAOffset = SA.getOffset(), SBOffset = SB.getOffset(); 696 int64_t Displacement = SA.getOffset() - SB.getOffset(); 697 if (Reverse) { 698 std::swap(FA, FB); 699 std::swap(SAOffset, SBOffset); 700 Displacement *= -1; 701 } 702 703 // Track whether B is before a relaxable instruction and whether A is after 704 // a relaxable instruction. If SA and SB are separated by a linker-relaxable 705 // instruction, the difference cannot be resolved as it may be changed by 706 // the linker. 707 bool BBeforeRelax = false, AAfterRelax = false; 708 for (auto FI = FB; FI; FI = FI->getNext()) { 709 auto DF = dyn_cast<MCDataFragment>(FI); 710 if (DF && DF->isLinkerRelaxable()) { 711 if (&*FI != FB || SBOffset != DF->getContents().size()) 712 BBeforeRelax = true; 713 if (&*FI != FA || SAOffset == DF->getContents().size()) 714 AAfterRelax = true; 715 if (BBeforeRelax && AAfterRelax) 716 return; 717 } 718 if (&*FI == FA) { 719 // If FA and FB belong to the same subsection, the loop will find FA and 720 // we can resolve the difference. 721 Addend += Reverse ? -Displacement : Displacement; 722 FinalizeFolding(); 723 return; 724 } 725 726 int64_t Num; 727 unsigned Count; 728 if (DF) { 729 Displacement += DF->getContents().size(); 730 } else if (auto *AF = dyn_cast<MCAlignFragment>(FI); 731 AF && Layout && AF->hasEmitNops() && 732 !Asm->getBackend().shouldInsertExtraNopBytesForCodeAlign( 733 *AF, Count)) { 734 Displacement += Asm->computeFragmentSize(*AF); 735 } else if (auto *FF = dyn_cast<MCFillFragment>(FI); 736 FF && FF->getNumValues().evaluateAsAbsolute(Num)) { 737 Displacement += Num * FF->getValueSize(); 738 } else { 739 return; 740 } 741 } 742 } 743 } 744 745 /// Evaluate the result of an add between (conceptually) two MCValues. 746 /// 747 /// This routine conceptually attempts to construct an MCValue: 748 /// Result = (Result_A - Result_B + Result_Cst) 749 /// from two MCValue's LHS and RHS where 750 /// Result = LHS + RHS 751 /// and 752 /// Result = (LHS_A - LHS_B + LHS_Cst) + (RHS_A - RHS_B + RHS_Cst). 753 /// 754 /// This routine attempts to aggressively fold the operands such that the result 755 /// is representable in an MCValue, but may not always succeed. 756 /// 757 /// \returns True on success, false if the result is not representable in an 758 /// MCValue. 759 760 /// NOTE: It is really important to have both the Asm and Layout arguments. 761 /// They might look redundant, but this function can be used before layout 762 /// is done (see the object streamer for example) and having the Asm argument 763 /// lets us avoid relaxations early. 764 static bool evaluateSymbolicAdd(const MCAssembler *Asm, 765 const SectionAddrMap *Addrs, bool InSet, 766 const MCValue &LHS, const MCValue &RHS, 767 MCValue &Res) { 768 // FIXME: This routine (and other evaluation parts) are *incredibly* sloppy 769 // about dealing with modifiers. This will ultimately bite us, one day. 770 const MCSymbolRefExpr *LHS_A = LHS.getSymA(); 771 const MCSymbolRefExpr *LHS_B = LHS.getSymB(); 772 int64_t LHS_Cst = LHS.getConstant(); 773 774 const MCSymbolRefExpr *RHS_A = RHS.getSymA(); 775 const MCSymbolRefExpr *RHS_B = RHS.getSymB(); 776 int64_t RHS_Cst = RHS.getConstant(); 777 778 if (LHS.getRefKind() != RHS.getRefKind()) 779 return false; 780 781 // Fold the result constant immediately. 782 int64_t Result_Cst = LHS_Cst + RHS_Cst; 783 784 // If we have a layout, we can fold resolved differences. 785 if (Asm) { 786 // First, fold out any differences which are fully resolved. By 787 // reassociating terms in 788 // Result = (LHS_A - LHS_B + LHS_Cst) + (RHS_A - RHS_B + RHS_Cst). 789 // we have the four possible differences: 790 // (LHS_A - LHS_B), 791 // (LHS_A - RHS_B), 792 // (RHS_A - LHS_B), 793 // (RHS_A - RHS_B). 794 // Since we are attempting to be as aggressive as possible about folding, we 795 // attempt to evaluate each possible alternative. 796 AttemptToFoldSymbolOffsetDifference(Asm, Addrs, InSet, LHS_A, LHS_B, 797 Result_Cst); 798 AttemptToFoldSymbolOffsetDifference(Asm, Addrs, InSet, LHS_A, RHS_B, 799 Result_Cst); 800 AttemptToFoldSymbolOffsetDifference(Asm, Addrs, InSet, RHS_A, LHS_B, 801 Result_Cst); 802 AttemptToFoldSymbolOffsetDifference(Asm, Addrs, InSet, RHS_A, RHS_B, 803 Result_Cst); 804 } 805 806 // We can't represent the addition or subtraction of two symbols. 807 if ((LHS_A && RHS_A) || (LHS_B && RHS_B)) 808 return false; 809 810 // At this point, we have at most one additive symbol and one subtractive 811 // symbol -- find them. 812 const MCSymbolRefExpr *A = LHS_A ? LHS_A : RHS_A; 813 const MCSymbolRefExpr *B = LHS_B ? LHS_B : RHS_B; 814 815 Res = MCValue::get(A, B, Result_Cst); 816 return true; 817 } 818 819 bool MCExpr::evaluateAsRelocatable(MCValue &Res, const MCAssembler *Asm, 820 const MCFixup *Fixup) const { 821 return evaluateAsRelocatableImpl(Res, Asm, Fixup, nullptr, false); 822 } 823 824 bool MCExpr::evaluateAsValue(MCValue &Res, const MCAssembler &Asm) const { 825 return evaluateAsRelocatableImpl(Res, &Asm, nullptr, nullptr, true); 826 } 827 828 static bool canExpand(const MCSymbol &Sym, bool InSet) { 829 if (Sym.isWeakExternal()) 830 return false; 831 832 const MCExpr *Expr = Sym.getVariableValue(); 833 const auto *Inner = dyn_cast<MCSymbolRefExpr>(Expr); 834 if (Inner) { 835 if (Inner->getKind() == MCSymbolRefExpr::VK_WEAKREF) 836 return false; 837 } 838 839 if (InSet) 840 return true; 841 return !Sym.isInSection(); 842 } 843 844 bool MCExpr::evaluateAsRelocatableImpl(MCValue &Res, const MCAssembler *Asm, 845 const MCFixup *Fixup, 846 const SectionAddrMap *Addrs, 847 bool InSet) const { 848 ++stats::MCExprEvaluate; 849 switch (getKind()) { 850 case Target: 851 return cast<MCTargetExpr>(this)->evaluateAsRelocatableImpl(Res, Asm, Fixup); 852 853 case Constant: 854 Res = MCValue::get(cast<MCConstantExpr>(this)->getValue()); 855 return true; 856 857 case SymbolRef: { 858 const MCSymbolRefExpr *SRE = cast<MCSymbolRefExpr>(this); 859 const MCSymbol &Sym = SRE->getSymbol(); 860 const auto Kind = SRE->getKind(); 861 bool Layout = Asm && Asm->hasLayout(); 862 863 // Evaluate recursively if this is a variable. 864 if (Sym.isVariable() && (Kind == MCSymbolRefExpr::VK_None || Layout) && 865 canExpand(Sym, InSet)) { 866 bool IsMachO = SRE->hasSubsectionsViaSymbols(); 867 if (Sym.getVariableValue()->evaluateAsRelocatableImpl( 868 Res, Asm, Fixup, Addrs, InSet || IsMachO)) { 869 if (Kind != MCSymbolRefExpr::VK_None) { 870 if (Res.isAbsolute()) { 871 Res = MCValue::get(SRE, nullptr, 0); 872 return true; 873 } 874 // If the reference has a variant kind, we can only handle expressions 875 // which evaluate exactly to a single unadorned symbol. Attach the 876 // original VariantKind to SymA of the result. 877 if (Res.getRefKind() != MCSymbolRefExpr::VK_None || !Res.getSymA() || 878 Res.getSymB() || Res.getConstant()) 879 return false; 880 Res = 881 MCValue::get(MCSymbolRefExpr::create(&Res.getSymA()->getSymbol(), 882 Kind, Asm->getContext()), 883 Res.getSymB(), Res.getConstant(), Res.getRefKind()); 884 } 885 if (!IsMachO) 886 return true; 887 888 const MCSymbolRefExpr *A = Res.getSymA(); 889 const MCSymbolRefExpr *B = Res.getSymB(); 890 // FIXME: This is small hack. Given 891 // a = b + 4 892 // .long a 893 // the OS X assembler will completely drop the 4. We should probably 894 // include it in the relocation or produce an error if that is not 895 // possible. 896 // Allow constant expressions. 897 if (!A && !B) 898 return true; 899 // Allows aliases with zero offset. 900 if (Res.getConstant() == 0 && (!A || !B)) 901 return true; 902 } 903 } 904 905 Res = MCValue::get(SRE, nullptr, 0); 906 return true; 907 } 908 909 case Unary: { 910 const MCUnaryExpr *AUE = cast<MCUnaryExpr>(this); 911 MCValue Value; 912 913 if (!AUE->getSubExpr()->evaluateAsRelocatableImpl(Value, Asm, Fixup, Addrs, 914 InSet)) 915 return false; 916 917 switch (AUE->getOpcode()) { 918 case MCUnaryExpr::LNot: 919 if (!Value.isAbsolute()) 920 return false; 921 Res = MCValue::get(!Value.getConstant()); 922 break; 923 case MCUnaryExpr::Minus: 924 /// -(a - b + const) ==> (b - a - const) 925 if (Value.getSymA() && !Value.getSymB()) 926 return false; 927 928 // The cast avoids undefined behavior if the constant is INT64_MIN. 929 Res = MCValue::get(Value.getSymB(), Value.getSymA(), 930 -(uint64_t)Value.getConstant()); 931 break; 932 case MCUnaryExpr::Not: 933 if (!Value.isAbsolute()) 934 return false; 935 Res = MCValue::get(~Value.getConstant()); 936 break; 937 case MCUnaryExpr::Plus: 938 Res = Value; 939 break; 940 } 941 942 return true; 943 } 944 945 case Binary: { 946 const MCBinaryExpr *ABE = cast<MCBinaryExpr>(this); 947 MCValue LHSValue, RHSValue; 948 949 if (!ABE->getLHS()->evaluateAsRelocatableImpl(LHSValue, Asm, Fixup, Addrs, 950 InSet) || 951 !ABE->getRHS()->evaluateAsRelocatableImpl(RHSValue, Asm, Fixup, Addrs, 952 InSet)) { 953 // Check if both are Target Expressions, see if we can compare them. 954 if (const MCTargetExpr *L = dyn_cast<MCTargetExpr>(ABE->getLHS())) { 955 if (const MCTargetExpr *R = dyn_cast<MCTargetExpr>(ABE->getRHS())) { 956 switch (ABE->getOpcode()) { 957 case MCBinaryExpr::EQ: 958 Res = MCValue::get(L->isEqualTo(R) ? -1 : 0); 959 return true; 960 case MCBinaryExpr::NE: 961 Res = MCValue::get(L->isEqualTo(R) ? 0 : -1); 962 return true; 963 default: 964 break; 965 } 966 } 967 } 968 return false; 969 } 970 971 // We only support a few operations on non-constant expressions, handle 972 // those first. 973 if (!LHSValue.isAbsolute() || !RHSValue.isAbsolute()) { 974 switch (ABE->getOpcode()) { 975 default: 976 return false; 977 case MCBinaryExpr::Sub: 978 // Negate RHS and add. 979 // The cast avoids undefined behavior if the constant is INT64_MIN. 980 return evaluateSymbolicAdd( 981 Asm, Addrs, InSet, LHSValue, 982 MCValue::get(RHSValue.getSymB(), RHSValue.getSymA(), 983 -(uint64_t)RHSValue.getConstant(), 984 RHSValue.getRefKind()), 985 Res); 986 987 case MCBinaryExpr::Add: 988 return evaluateSymbolicAdd( 989 Asm, Addrs, InSet, LHSValue, 990 MCValue::get(RHSValue.getSymA(), RHSValue.getSymB(), 991 RHSValue.getConstant(), RHSValue.getRefKind()), 992 Res); 993 } 994 } 995 996 // FIXME: We need target hooks for the evaluation. It may be limited in 997 // width, and gas defines the result of comparisons differently from 998 // Apple as. 999 int64_t LHS = LHSValue.getConstant(), RHS = RHSValue.getConstant(); 1000 int64_t Result = 0; 1001 auto Op = ABE->getOpcode(); 1002 switch (Op) { 1003 case MCBinaryExpr::AShr: Result = LHS >> RHS; break; 1004 case MCBinaryExpr::Add: Result = LHS + RHS; break; 1005 case MCBinaryExpr::And: Result = LHS & RHS; break; 1006 case MCBinaryExpr::Div: 1007 case MCBinaryExpr::Mod: 1008 // Handle division by zero. gas just emits a warning and keeps going, 1009 // we try to be stricter. 1010 // FIXME: Currently the caller of this function has no way to understand 1011 // we're bailing out because of 'division by zero'. Therefore, it will 1012 // emit a 'expected relocatable expression' error. It would be nice to 1013 // change this code to emit a better diagnostic. 1014 if (RHS == 0) 1015 return false; 1016 if (ABE->getOpcode() == MCBinaryExpr::Div) 1017 Result = LHS / RHS; 1018 else 1019 Result = LHS % RHS; 1020 break; 1021 case MCBinaryExpr::EQ: Result = LHS == RHS; break; 1022 case MCBinaryExpr::GT: Result = LHS > RHS; break; 1023 case MCBinaryExpr::GTE: Result = LHS >= RHS; break; 1024 case MCBinaryExpr::LAnd: Result = LHS && RHS; break; 1025 case MCBinaryExpr::LOr: Result = LHS || RHS; break; 1026 case MCBinaryExpr::LShr: Result = uint64_t(LHS) >> uint64_t(RHS); break; 1027 case MCBinaryExpr::LT: Result = LHS < RHS; break; 1028 case MCBinaryExpr::LTE: Result = LHS <= RHS; break; 1029 case MCBinaryExpr::Mul: Result = LHS * RHS; break; 1030 case MCBinaryExpr::NE: Result = LHS != RHS; break; 1031 case MCBinaryExpr::Or: Result = LHS | RHS; break; 1032 case MCBinaryExpr::OrNot: Result = LHS | ~RHS; break; 1033 case MCBinaryExpr::Shl: Result = uint64_t(LHS) << uint64_t(RHS); break; 1034 case MCBinaryExpr::Sub: Result = LHS - RHS; break; 1035 case MCBinaryExpr::Xor: Result = LHS ^ RHS; break; 1036 } 1037 1038 switch (Op) { 1039 default: 1040 Res = MCValue::get(Result); 1041 break; 1042 case MCBinaryExpr::EQ: 1043 case MCBinaryExpr::GT: 1044 case MCBinaryExpr::GTE: 1045 case MCBinaryExpr::LT: 1046 case MCBinaryExpr::LTE: 1047 case MCBinaryExpr::NE: 1048 // A comparison operator returns a -1 if true and 0 if false. 1049 Res = MCValue::get(Result ? -1 : 0); 1050 break; 1051 } 1052 1053 return true; 1054 } 1055 } 1056 1057 llvm_unreachable("Invalid assembly expression kind!"); 1058 } 1059 1060 MCFragment *MCExpr::findAssociatedFragment() const { 1061 switch (getKind()) { 1062 case Target: 1063 // We never look through target specific expressions. 1064 return cast<MCTargetExpr>(this)->findAssociatedFragment(); 1065 1066 case Constant: 1067 return MCSymbol::AbsolutePseudoFragment; 1068 1069 case SymbolRef: { 1070 const MCSymbolRefExpr *SRE = cast<MCSymbolRefExpr>(this); 1071 const MCSymbol &Sym = SRE->getSymbol(); 1072 return Sym.getFragment(); 1073 } 1074 1075 case Unary: 1076 return cast<MCUnaryExpr>(this)->getSubExpr()->findAssociatedFragment(); 1077 1078 case Binary: { 1079 const MCBinaryExpr *BE = cast<MCBinaryExpr>(this); 1080 MCFragment *LHS_F = BE->getLHS()->findAssociatedFragment(); 1081 MCFragment *RHS_F = BE->getRHS()->findAssociatedFragment(); 1082 1083 // If either is absolute, return the other. 1084 if (LHS_F == MCSymbol::AbsolutePseudoFragment) 1085 return RHS_F; 1086 if (RHS_F == MCSymbol::AbsolutePseudoFragment) 1087 return LHS_F; 1088 1089 // Not always correct, but probably the best we can do without more context. 1090 if (BE->getOpcode() == MCBinaryExpr::Sub) 1091 return MCSymbol::AbsolutePseudoFragment; 1092 1093 // Otherwise, return the first non-null fragment. 1094 return LHS_F ? LHS_F : RHS_F; 1095 } 1096 } 1097 1098 llvm_unreachable("Invalid assembly expression kind!"); 1099 } 1100