MCExpr.cpp revision 36b56886974eae4f9c5ebc96befd3e7bfe5de338
1//===- MCExpr.cpp - Assembly Level Expression Implementation --------------===// 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#define DEBUG_TYPE "mcexpr" 11#include "llvm/MC/MCExpr.h" 12#include "llvm/ADT/Statistic.h" 13#include "llvm/ADT/StringSwitch.h" 14#include "llvm/MC/MCAsmInfo.h" 15#include "llvm/MC/MCAsmLayout.h" 16#include "llvm/MC/MCAssembler.h" 17#include "llvm/MC/MCContext.h" 18#include "llvm/MC/MCObjectWriter.h" 19#include "llvm/MC/MCSymbol.h" 20#include "llvm/MC/MCValue.h" 21#include "llvm/Support/Debug.h" 22#include "llvm/Support/ErrorHandling.h" 23#include "llvm/Support/raw_ostream.h" 24using namespace llvm; 25 26namespace { 27namespace stats { 28STATISTIC(MCExprEvaluate, "Number of MCExpr evaluations"); 29} 30} 31 32void MCExpr::print(raw_ostream &OS) const { 33 switch (getKind()) { 34 case MCExpr::Target: 35 return cast<MCTargetExpr>(this)->PrintImpl(OS); 36 case MCExpr::Constant: 37 OS << cast<MCConstantExpr>(*this).getValue(); 38 return; 39 40 case MCExpr::SymbolRef: { 41 const MCSymbolRefExpr &SRE = cast<MCSymbolRefExpr>(*this); 42 const MCSymbol &Sym = SRE.getSymbol(); 43 // Parenthesize names that start with $ so that they don't look like 44 // absolute names. 45 bool UseParens = Sym.getName()[0] == '$'; 46 if (UseParens) 47 OS << '(' << Sym << ')'; 48 else 49 OS << Sym; 50 51 if (SRE.getKind() != MCSymbolRefExpr::VK_None) { 52 if (SRE.getMCAsmInfo().useParensForSymbolVariant()) 53 OS << '(' << MCSymbolRefExpr::getVariantKindName(SRE.getKind()) << ')'; 54 else 55 OS << '@' << MCSymbolRefExpr::getVariantKindName(SRE.getKind()); 56 } 57 58 return; 59 } 60 61 case MCExpr::Unary: { 62 const MCUnaryExpr &UE = cast<MCUnaryExpr>(*this); 63 switch (UE.getOpcode()) { 64 case MCUnaryExpr::LNot: OS << '!'; break; 65 case MCUnaryExpr::Minus: OS << '-'; break; 66 case MCUnaryExpr::Not: OS << '~'; break; 67 case MCUnaryExpr::Plus: OS << '+'; break; 68 } 69 OS << *UE.getSubExpr(); 70 return; 71 } 72 73 case MCExpr::Binary: { 74 const MCBinaryExpr &BE = cast<MCBinaryExpr>(*this); 75 76 // Only print parens around the LHS if it is non-trivial. 77 if (isa<MCConstantExpr>(BE.getLHS()) || isa<MCSymbolRefExpr>(BE.getLHS())) { 78 OS << *BE.getLHS(); 79 } else { 80 OS << '(' << *BE.getLHS() << ')'; 81 } 82 83 switch (BE.getOpcode()) { 84 case MCBinaryExpr::Add: 85 // Print "X-42" instead of "X+-42". 86 if (const MCConstantExpr *RHSC = dyn_cast<MCConstantExpr>(BE.getRHS())) { 87 if (RHSC->getValue() < 0) { 88 OS << RHSC->getValue(); 89 return; 90 } 91 } 92 93 OS << '+'; 94 break; 95 case MCBinaryExpr::And: OS << '&'; break; 96 case MCBinaryExpr::Div: OS << '/'; break; 97 case MCBinaryExpr::EQ: OS << "=="; break; 98 case MCBinaryExpr::GT: OS << '>'; break; 99 case MCBinaryExpr::GTE: OS << ">="; break; 100 case MCBinaryExpr::LAnd: OS << "&&"; break; 101 case MCBinaryExpr::LOr: OS << "||"; break; 102 case MCBinaryExpr::LT: OS << '<'; break; 103 case MCBinaryExpr::LTE: OS << "<="; break; 104 case MCBinaryExpr::Mod: OS << '%'; break; 105 case MCBinaryExpr::Mul: OS << '*'; break; 106 case MCBinaryExpr::NE: OS << "!="; break; 107 case MCBinaryExpr::Or: OS << '|'; break; 108 case MCBinaryExpr::Shl: OS << "<<"; break; 109 case MCBinaryExpr::Shr: OS << ">>"; break; 110 case MCBinaryExpr::Sub: OS << '-'; break; 111 case MCBinaryExpr::Xor: OS << '^'; break; 112 } 113 114 // Only print parens around the LHS if it is non-trivial. 115 if (isa<MCConstantExpr>(BE.getRHS()) || isa<MCSymbolRefExpr>(BE.getRHS())) { 116 OS << *BE.getRHS(); 117 } else { 118 OS << '(' << *BE.getRHS() << ')'; 119 } 120 return; 121 } 122 } 123 124 llvm_unreachable("Invalid expression kind!"); 125} 126 127#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) 128void MCExpr::dump() const { 129 print(dbgs()); 130 dbgs() << '\n'; 131} 132#endif 133 134/* *** */ 135 136const MCBinaryExpr *MCBinaryExpr::Create(Opcode Opc, const MCExpr *LHS, 137 const MCExpr *RHS, MCContext &Ctx) { 138 return new (Ctx) MCBinaryExpr(Opc, LHS, RHS); 139} 140 141const MCUnaryExpr *MCUnaryExpr::Create(Opcode Opc, const MCExpr *Expr, 142 MCContext &Ctx) { 143 return new (Ctx) MCUnaryExpr(Opc, Expr); 144} 145 146const MCConstantExpr *MCConstantExpr::Create(int64_t Value, MCContext &Ctx) { 147 return new (Ctx) MCConstantExpr(Value); 148} 149 150/* *** */ 151 152const MCSymbolRefExpr *MCSymbolRefExpr::Create(const MCSymbol *Sym, 153 VariantKind Kind, 154 MCContext &Ctx) { 155 return new (Ctx) MCSymbolRefExpr(Sym, Kind, Ctx.getAsmInfo()); 156} 157 158const MCSymbolRefExpr *MCSymbolRefExpr::Create(StringRef Name, VariantKind Kind, 159 MCContext &Ctx) { 160 return Create(Ctx.GetOrCreateSymbol(Name), Kind, Ctx); 161} 162 163StringRef MCSymbolRefExpr::getVariantKindName(VariantKind Kind) { 164 switch (Kind) { 165 case VK_Invalid: return "<<invalid>>"; 166 case VK_None: return "<<none>>"; 167 168 case VK_GOT: return "GOT"; 169 case VK_GOTOFF: return "GOTOFF"; 170 case VK_GOTPCREL: return "GOTPCREL"; 171 case VK_GOTTPOFF: return "GOTTPOFF"; 172 case VK_INDNTPOFF: return "INDNTPOFF"; 173 case VK_NTPOFF: return "NTPOFF"; 174 case VK_GOTNTPOFF: return "GOTNTPOFF"; 175 case VK_PLT: return "PLT"; 176 case VK_TLSGD: return "TLSGD"; 177 case VK_TLSLD: return "TLSLD"; 178 case VK_TLSLDM: return "TLSLDM"; 179 case VK_TPOFF: return "TPOFF"; 180 case VK_DTPOFF: return "DTPOFF"; 181 case VK_TLVP: return "TLVP"; 182 case VK_TLVPPAGE: return "TLVPPAGE"; 183 case VK_TLVPPAGEOFF: return "TLVPPAGEOFF"; 184 case VK_PAGE: return "PAGE"; 185 case VK_PAGEOFF: return "PAGEOFF"; 186 case VK_GOTPAGE: return "GOTPAGE"; 187 case VK_GOTPAGEOFF: return "GOTPAGEOFF"; 188 case VK_SECREL: return "SECREL32"; 189 case VK_WEAKREF: return "WEAKREF"; 190 case VK_ARM_NONE: return "none"; 191 case VK_ARM_TARGET1: return "target1"; 192 case VK_ARM_TARGET2: return "target2"; 193 case VK_ARM_PREL31: return "prel31"; 194 case VK_ARM_TLSLDO: return "tlsldo"; 195 case VK_ARM_TLSCALL: return "tlscall"; 196 case VK_ARM_TLSDESC: return "tlsdesc"; 197 case VK_ARM_TLSDESCSEQ: return "tlsdescseq"; 198 case VK_PPC_LO: return "l"; 199 case VK_PPC_HI: return "h"; 200 case VK_PPC_HA: return "ha"; 201 case VK_PPC_HIGHER: return "higher"; 202 case VK_PPC_HIGHERA: return "highera"; 203 case VK_PPC_HIGHEST: return "highest"; 204 case VK_PPC_HIGHESTA: return "highesta"; 205 case VK_PPC_GOT_LO: return "got@l"; 206 case VK_PPC_GOT_HI: return "got@h"; 207 case VK_PPC_GOT_HA: return "got@ha"; 208 case VK_PPC_TOCBASE: return "tocbase"; 209 case VK_PPC_TOC: return "toc"; 210 case VK_PPC_TOC_LO: return "toc@l"; 211 case VK_PPC_TOC_HI: return "toc@h"; 212 case VK_PPC_TOC_HA: return "toc@ha"; 213 case VK_PPC_DTPMOD: return "dtpmod"; 214 case VK_PPC_TPREL: return "tprel"; 215 case VK_PPC_TPREL_LO: return "tprel@l"; 216 case VK_PPC_TPREL_HI: return "tprel@h"; 217 case VK_PPC_TPREL_HA: return "tprel@ha"; 218 case VK_PPC_TPREL_HIGHER: return "tprel@higher"; 219 case VK_PPC_TPREL_HIGHERA: return "tprel@highera"; 220 case VK_PPC_TPREL_HIGHEST: return "tprel@highest"; 221 case VK_PPC_TPREL_HIGHESTA: return "tprel@highesta"; 222 case VK_PPC_DTPREL: return "dtprel"; 223 case VK_PPC_DTPREL_LO: return "dtprel@l"; 224 case VK_PPC_DTPREL_HI: return "dtprel@h"; 225 case VK_PPC_DTPREL_HA: return "dtprel@ha"; 226 case VK_PPC_DTPREL_HIGHER: return "dtprel@higher"; 227 case VK_PPC_DTPREL_HIGHERA: return "dtprel@highera"; 228 case VK_PPC_DTPREL_HIGHEST: return "dtprel@highest"; 229 case VK_PPC_DTPREL_HIGHESTA: return "dtprel@highesta"; 230 case VK_PPC_GOT_TPREL: return "got@tprel"; 231 case VK_PPC_GOT_TPREL_LO: return "got@tprel@l"; 232 case VK_PPC_GOT_TPREL_HI: return "got@tprel@h"; 233 case VK_PPC_GOT_TPREL_HA: return "got@tprel@ha"; 234 case VK_PPC_GOT_DTPREL: return "got@dtprel"; 235 case VK_PPC_GOT_DTPREL_LO: return "got@dtprel@l"; 236 case VK_PPC_GOT_DTPREL_HI: return "got@dtprel@h"; 237 case VK_PPC_GOT_DTPREL_HA: return "got@dtprel@ha"; 238 case VK_PPC_TLS: return "tls"; 239 case VK_PPC_GOT_TLSGD: return "got@tlsgd"; 240 case VK_PPC_GOT_TLSGD_LO: return "got@tlsgd@l"; 241 case VK_PPC_GOT_TLSGD_HI: return "got@tlsgd@h"; 242 case VK_PPC_GOT_TLSGD_HA: return "got@tlsgd@ha"; 243 case VK_PPC_TLSGD: return "tlsgd"; 244 case VK_PPC_GOT_TLSLD: return "got@tlsld"; 245 case VK_PPC_GOT_TLSLD_LO: return "got@tlsld@l"; 246 case VK_PPC_GOT_TLSLD_HI: return "got@tlsld@h"; 247 case VK_PPC_GOT_TLSLD_HA: return "got@tlsld@ha"; 248 case VK_PPC_TLSLD: return "tlsld"; 249 case VK_Mips_GPREL: return "GPREL"; 250 case VK_Mips_GOT_CALL: return "GOT_CALL"; 251 case VK_Mips_GOT16: return "GOT16"; 252 case VK_Mips_GOT: return "GOT"; 253 case VK_Mips_ABS_HI: return "ABS_HI"; 254 case VK_Mips_ABS_LO: return "ABS_LO"; 255 case VK_Mips_TLSGD: return "TLSGD"; 256 case VK_Mips_TLSLDM: return "TLSLDM"; 257 case VK_Mips_DTPREL_HI: return "DTPREL_HI"; 258 case VK_Mips_DTPREL_LO: return "DTPREL_LO"; 259 case VK_Mips_GOTTPREL: return "GOTTPREL"; 260 case VK_Mips_TPREL_HI: return "TPREL_HI"; 261 case VK_Mips_TPREL_LO: return "TPREL_LO"; 262 case VK_Mips_GPOFF_HI: return "GPOFF_HI"; 263 case VK_Mips_GPOFF_LO: return "GPOFF_LO"; 264 case VK_Mips_GOT_DISP: return "GOT_DISP"; 265 case VK_Mips_GOT_PAGE: return "GOT_PAGE"; 266 case VK_Mips_GOT_OFST: return "GOT_OFST"; 267 case VK_Mips_HIGHER: return "HIGHER"; 268 case VK_Mips_HIGHEST: return "HIGHEST"; 269 case VK_Mips_GOT_HI16: return "GOT_HI16"; 270 case VK_Mips_GOT_LO16: return "GOT_LO16"; 271 case VK_Mips_CALL_HI16: return "CALL_HI16"; 272 case VK_Mips_CALL_LO16: return "CALL_LO16"; 273 case VK_COFF_IMGREL32: return "IMGREL32"; 274 } 275 llvm_unreachable("Invalid variant kind"); 276} 277 278MCSymbolRefExpr::VariantKind 279MCSymbolRefExpr::getVariantKindForName(StringRef Name) { 280 return StringSwitch<VariantKind>(Name) 281 .Case("GOT", VK_GOT) 282 .Case("got", VK_GOT) 283 .Case("GOTOFF", VK_GOTOFF) 284 .Case("gotoff", VK_GOTOFF) 285 .Case("GOTPCREL", VK_GOTPCREL) 286 .Case("gotpcrel", VK_GOTPCREL) 287 .Case("GOTTPOFF", VK_GOTTPOFF) 288 .Case("gottpoff", VK_GOTTPOFF) 289 .Case("INDNTPOFF", VK_INDNTPOFF) 290 .Case("indntpoff", VK_INDNTPOFF) 291 .Case("NTPOFF", VK_NTPOFF) 292 .Case("ntpoff", VK_NTPOFF) 293 .Case("GOTNTPOFF", VK_GOTNTPOFF) 294 .Case("gotntpoff", VK_GOTNTPOFF) 295 .Case("PLT", VK_PLT) 296 .Case("plt", VK_PLT) 297 .Case("TLSGD", VK_TLSGD) 298 .Case("tlsgd", VK_TLSGD) 299 .Case("TLSLD", VK_TLSLD) 300 .Case("tlsld", VK_TLSLD) 301 .Case("TLSLDM", VK_TLSLDM) 302 .Case("tlsldm", VK_TLSLDM) 303 .Case("TPOFF", VK_TPOFF) 304 .Case("tpoff", VK_TPOFF) 305 .Case("DTPOFF", VK_DTPOFF) 306 .Case("dtpoff", VK_DTPOFF) 307 .Case("TLVP", VK_TLVP) 308 .Case("tlvp", VK_TLVP) 309 .Case("TLVPPAGE", VK_TLVPPAGE) 310 .Case("tlvppage", VK_TLVPPAGE) 311 .Case("TLVPPAGEOFF", VK_TLVPPAGEOFF) 312 .Case("tlvppageoff", VK_TLVPPAGEOFF) 313 .Case("PAGE", VK_PAGE) 314 .Case("page", VK_PAGE) 315 .Case("PAGEOFF", VK_PAGEOFF) 316 .Case("pageoff", VK_PAGEOFF) 317 .Case("GOTPAGE", VK_GOTPAGE) 318 .Case("gotpage", VK_GOTPAGE) 319 .Case("GOTPAGEOFF", VK_GOTPAGEOFF) 320 .Case("gotpageoff", VK_GOTPAGEOFF) 321 .Case("IMGREL", VK_COFF_IMGREL32) 322 .Case("imgrel", VK_COFF_IMGREL32) 323 .Case("SECREL32", VK_SECREL) 324 .Case("secrel32", VK_SECREL) 325 .Case("L", VK_PPC_LO) 326 .Case("l", VK_PPC_LO) 327 .Case("H", VK_PPC_HI) 328 .Case("h", VK_PPC_HI) 329 .Case("HA", VK_PPC_HA) 330 .Case("ha", VK_PPC_HA) 331 .Case("HIGHER", VK_PPC_HIGHER) 332 .Case("higher", VK_PPC_HIGHER) 333 .Case("HIGHERA", VK_PPC_HIGHERA) 334 .Case("highera", VK_PPC_HIGHERA) 335 .Case("HIGHEST", VK_PPC_HIGHEST) 336 .Case("highest", VK_PPC_HIGHEST) 337 .Case("HIGHESTA", VK_PPC_HIGHESTA) 338 .Case("highesta", VK_PPC_HIGHESTA) 339 .Case("GOT@L", VK_PPC_GOT_LO) 340 .Case("got@l", VK_PPC_GOT_LO) 341 .Case("GOT@H", VK_PPC_GOT_HI) 342 .Case("got@h", VK_PPC_GOT_HI) 343 .Case("GOT@HA", VK_PPC_GOT_HA) 344 .Case("got@ha", VK_PPC_GOT_HA) 345 .Case("TOCBASE", VK_PPC_TOCBASE) 346 .Case("tocbase", VK_PPC_TOCBASE) 347 .Case("TOC", VK_PPC_TOC) 348 .Case("toc", VK_PPC_TOC) 349 .Case("TOC@L", VK_PPC_TOC_LO) 350 .Case("toc@l", VK_PPC_TOC_LO) 351 .Case("TOC@H", VK_PPC_TOC_HI) 352 .Case("toc@h", VK_PPC_TOC_HI) 353 .Case("TOC@HA", VK_PPC_TOC_HA) 354 .Case("toc@ha", VK_PPC_TOC_HA) 355 .Case("TLS", VK_PPC_TLS) 356 .Case("tls", VK_PPC_TLS) 357 .Case("DTPMOD", VK_PPC_DTPMOD) 358 .Case("dtpmod", VK_PPC_DTPMOD) 359 .Case("TPREL", VK_PPC_TPREL) 360 .Case("tprel", VK_PPC_TPREL) 361 .Case("TPREL@L", VK_PPC_TPREL_LO) 362 .Case("tprel@l", VK_PPC_TPREL_LO) 363 .Case("TPREL@H", VK_PPC_TPREL_HI) 364 .Case("tprel@h", VK_PPC_TPREL_HI) 365 .Case("TPREL@HA", VK_PPC_TPREL_HA) 366 .Case("tprel@ha", VK_PPC_TPREL_HA) 367 .Case("TPREL@HIGHER", VK_PPC_TPREL_HIGHER) 368 .Case("tprel@higher", VK_PPC_TPREL_HIGHER) 369 .Case("TPREL@HIGHERA", VK_PPC_TPREL_HIGHERA) 370 .Case("tprel@highera", VK_PPC_TPREL_HIGHERA) 371 .Case("TPREL@HIGHEST", VK_PPC_TPREL_HIGHEST) 372 .Case("tprel@highest", VK_PPC_TPREL_HIGHEST) 373 .Case("TPREL@HIGHESTA", VK_PPC_TPREL_HIGHESTA) 374 .Case("tprel@highesta", VK_PPC_TPREL_HIGHESTA) 375 .Case("DTPREL", VK_PPC_DTPREL) 376 .Case("dtprel", VK_PPC_DTPREL) 377 .Case("DTPREL@L", VK_PPC_DTPREL_LO) 378 .Case("dtprel@l", VK_PPC_DTPREL_LO) 379 .Case("DTPREL@H", VK_PPC_DTPREL_HI) 380 .Case("dtprel@h", VK_PPC_DTPREL_HI) 381 .Case("DTPREL@HA", VK_PPC_DTPREL_HA) 382 .Case("dtprel@ha", VK_PPC_DTPREL_HA) 383 .Case("DTPREL@HIGHER", VK_PPC_DTPREL_HIGHER) 384 .Case("dtprel@higher", VK_PPC_DTPREL_HIGHER) 385 .Case("DTPREL@HIGHERA", VK_PPC_DTPREL_HIGHERA) 386 .Case("dtprel@highera", VK_PPC_DTPREL_HIGHERA) 387 .Case("DTPREL@HIGHEST", VK_PPC_DTPREL_HIGHEST) 388 .Case("dtprel@highest", VK_PPC_DTPREL_HIGHEST) 389 .Case("DTPREL@HIGHESTA", VK_PPC_DTPREL_HIGHESTA) 390 .Case("dtprel@highesta", VK_PPC_DTPREL_HIGHESTA) 391 .Case("GOT@TPREL", VK_PPC_GOT_TPREL) 392 .Case("got@tprel", VK_PPC_GOT_TPREL) 393 .Case("GOT@TPREL@L", VK_PPC_GOT_TPREL_LO) 394 .Case("got@tprel@l", VK_PPC_GOT_TPREL_LO) 395 .Case("GOT@TPREL@H", VK_PPC_GOT_TPREL_HI) 396 .Case("got@tprel@h", VK_PPC_GOT_TPREL_HI) 397 .Case("GOT@TPREL@HA", VK_PPC_GOT_TPREL_HA) 398 .Case("got@tprel@ha", VK_PPC_GOT_TPREL_HA) 399 .Case("GOT@DTPREL", VK_PPC_GOT_DTPREL) 400 .Case("got@dtprel", VK_PPC_GOT_DTPREL) 401 .Case("GOT@DTPREL@L", VK_PPC_GOT_DTPREL_LO) 402 .Case("got@dtprel@l", VK_PPC_GOT_DTPREL_LO) 403 .Case("GOT@DTPREL@H", VK_PPC_GOT_DTPREL_HI) 404 .Case("got@dtprel@h", VK_PPC_GOT_DTPREL_HI) 405 .Case("GOT@DTPREL@HA", VK_PPC_GOT_DTPREL_HA) 406 .Case("got@dtprel@ha", VK_PPC_GOT_DTPREL_HA) 407 .Case("GOT@TLSGD", VK_PPC_GOT_TLSGD) 408 .Case("got@tlsgd", VK_PPC_GOT_TLSGD) 409 .Case("GOT@TLSGD@L", VK_PPC_GOT_TLSGD_LO) 410 .Case("got@tlsgd@l", VK_PPC_GOT_TLSGD_LO) 411 .Case("GOT@TLSGD@H", VK_PPC_GOT_TLSGD_HI) 412 .Case("got@tlsgd@h", VK_PPC_GOT_TLSGD_HI) 413 .Case("GOT@TLSGD@HA", VK_PPC_GOT_TLSGD_HA) 414 .Case("got@tlsgd@ha", VK_PPC_GOT_TLSGD_HA) 415 .Case("GOT@TLSLD", VK_PPC_GOT_TLSLD) 416 .Case("got@tlsld", VK_PPC_GOT_TLSLD) 417 .Case("GOT@TLSLD@L", VK_PPC_GOT_TLSLD_LO) 418 .Case("got@tlsld@l", VK_PPC_GOT_TLSLD_LO) 419 .Case("GOT@TLSLD@H", VK_PPC_GOT_TLSLD_HI) 420 .Case("got@tlsld@h", VK_PPC_GOT_TLSLD_HI) 421 .Case("GOT@TLSLD@HA", VK_PPC_GOT_TLSLD_HA) 422 .Case("got@tlsld@ha", VK_PPC_GOT_TLSLD_HA) 423 .Case("NONE", VK_ARM_NONE) 424 .Case("none", VK_ARM_NONE) 425 .Case("TARGET1", VK_ARM_TARGET1) 426 .Case("target1", VK_ARM_TARGET1) 427 .Case("TARGET2", VK_ARM_TARGET2) 428 .Case("target2", VK_ARM_TARGET2) 429 .Case("PREL31", VK_ARM_PREL31) 430 .Case("prel31", VK_ARM_PREL31) 431 .Case("TLSLDO", VK_ARM_TLSLDO) 432 .Case("tlsldo", VK_ARM_TLSLDO) 433 .Case("TLSCALL", VK_ARM_TLSCALL) 434 .Case("tlscall", VK_ARM_TLSCALL) 435 .Case("TLSDESC", VK_ARM_TLSDESC) 436 .Case("tlsdesc", VK_ARM_TLSDESC) 437 .Default(VK_Invalid); 438} 439 440/* *** */ 441 442void MCTargetExpr::anchor() {} 443 444/* *** */ 445 446bool MCExpr::EvaluateAsAbsolute(int64_t &Res) const { 447 return EvaluateAsAbsolute(Res, 0, 0, 0); 448} 449 450bool MCExpr::EvaluateAsAbsolute(int64_t &Res, 451 const MCAsmLayout &Layout) const { 452 return EvaluateAsAbsolute(Res, &Layout.getAssembler(), &Layout, 0); 453} 454 455bool MCExpr::EvaluateAsAbsolute(int64_t &Res, 456 const MCAsmLayout &Layout, 457 const SectionAddrMap &Addrs) const { 458 return EvaluateAsAbsolute(Res, &Layout.getAssembler(), &Layout, &Addrs); 459} 460 461bool MCExpr::EvaluateAsAbsolute(int64_t &Res, const MCAssembler &Asm) const { 462 return EvaluateAsAbsolute(Res, &Asm, 0, 0); 463} 464 465bool MCExpr::EvaluateAsAbsolute(int64_t &Res, const MCAssembler *Asm, 466 const MCAsmLayout *Layout, 467 const SectionAddrMap *Addrs) const { 468 MCValue Value; 469 470 // Fast path constants. 471 if (const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(this)) { 472 Res = CE->getValue(); 473 return true; 474 } 475 476 // FIXME: The use if InSet = Addrs is a hack. Setting InSet causes us 477 // absolutize differences across sections and that is what the MachO writer 478 // uses Addrs for. 479 bool IsRelocatable = 480 EvaluateAsRelocatableImpl(Value, Asm, Layout, Addrs, /*InSet*/ Addrs); 481 482 // Record the current value. 483 Res = Value.getConstant(); 484 485 return IsRelocatable && Value.isAbsolute(); 486} 487 488/// \brief Helper method for \see EvaluateSymbolAdd(). 489static void AttemptToFoldSymbolOffsetDifference(const MCAssembler *Asm, 490 const MCAsmLayout *Layout, 491 const SectionAddrMap *Addrs, 492 bool InSet, 493 const MCSymbolRefExpr *&A, 494 const MCSymbolRefExpr *&B, 495 int64_t &Addend) { 496 if (!A || !B) 497 return; 498 499 const MCSymbol &SA = A->getSymbol(); 500 const MCSymbol &SB = B->getSymbol(); 501 502 if (SA.isUndefined() || SB.isUndefined()) 503 return; 504 505 if (!Asm->getWriter().IsSymbolRefDifferenceFullyResolved(*Asm, A, B, InSet)) 506 return; 507 508 MCSymbolData &AD = Asm->getSymbolData(SA); 509 MCSymbolData &BD = Asm->getSymbolData(SB); 510 511 if (AD.getFragment() == BD.getFragment()) { 512 Addend += (AD.getOffset() - BD.getOffset()); 513 514 // Pointers to Thumb symbols need to have their low-bit set to allow 515 // for interworking. 516 if (Asm->isThumbFunc(&SA)) 517 Addend |= 1; 518 519 // Clear the symbol expr pointers to indicate we have folded these 520 // operands. 521 A = B = 0; 522 return; 523 } 524 525 if (!Layout) 526 return; 527 528 const MCSectionData &SecA = *AD.getFragment()->getParent(); 529 const MCSectionData &SecB = *BD.getFragment()->getParent(); 530 531 if ((&SecA != &SecB) && !Addrs) 532 return; 533 534 // Eagerly evaluate. 535 Addend += (Layout->getSymbolOffset(&Asm->getSymbolData(A->getSymbol())) - 536 Layout->getSymbolOffset(&Asm->getSymbolData(B->getSymbol()))); 537 if (Addrs && (&SecA != &SecB)) 538 Addend += (Addrs->lookup(&SecA) - Addrs->lookup(&SecB)); 539 540 // Pointers to Thumb symbols need to have their low-bit set to allow 541 // for interworking. 542 if (Asm->isThumbFunc(&SA)) 543 Addend |= 1; 544 545 // Clear the symbol expr pointers to indicate we have folded these 546 // operands. 547 A = B = 0; 548} 549 550/// \brief Evaluate the result of an add between (conceptually) two MCValues. 551/// 552/// This routine conceptually attempts to construct an MCValue: 553/// Result = (Result_A - Result_B + Result_Cst) 554/// from two MCValue's LHS and RHS where 555/// Result = LHS + RHS 556/// and 557/// Result = (LHS_A - LHS_B + LHS_Cst) + (RHS_A - RHS_B + RHS_Cst). 558/// 559/// This routine attempts to aggresively fold the operands such that the result 560/// is representable in an MCValue, but may not always succeed. 561/// 562/// \returns True on success, false if the result is not representable in an 563/// MCValue. 564 565/// NOTE: It is really important to have both the Asm and Layout arguments. 566/// They might look redundant, but this function can be used before layout 567/// is done (see the object streamer for example) and having the Asm argument 568/// lets us avoid relaxations early. 569static bool EvaluateSymbolicAdd(const MCAssembler *Asm, 570 const MCAsmLayout *Layout, 571 const SectionAddrMap *Addrs, 572 bool InSet, 573 const MCValue &LHS,const MCSymbolRefExpr *RHS_A, 574 const MCSymbolRefExpr *RHS_B, int64_t RHS_Cst, 575 MCValue &Res) { 576 // FIXME: This routine (and other evaluation parts) are *incredibly* sloppy 577 // about dealing with modifiers. This will ultimately bite us, one day. 578 const MCSymbolRefExpr *LHS_A = LHS.getSymA(); 579 const MCSymbolRefExpr *LHS_B = LHS.getSymB(); 580 int64_t LHS_Cst = LHS.getConstant(); 581 582 // Fold the result constant immediately. 583 int64_t Result_Cst = LHS_Cst + RHS_Cst; 584 585 assert((!Layout || Asm) && 586 "Must have an assembler object if layout is given!"); 587 588 // If we have a layout, we can fold resolved differences. 589 if (Asm) { 590 // First, fold out any differences which are fully resolved. By 591 // reassociating terms in 592 // Result = (LHS_A - LHS_B + LHS_Cst) + (RHS_A - RHS_B + RHS_Cst). 593 // we have the four possible differences: 594 // (LHS_A - LHS_B), 595 // (LHS_A - RHS_B), 596 // (RHS_A - LHS_B), 597 // (RHS_A - RHS_B). 598 // Since we are attempting to be as aggressive as possible about folding, we 599 // attempt to evaluate each possible alternative. 600 AttemptToFoldSymbolOffsetDifference(Asm, Layout, Addrs, InSet, LHS_A, LHS_B, 601 Result_Cst); 602 AttemptToFoldSymbolOffsetDifference(Asm, Layout, Addrs, InSet, LHS_A, RHS_B, 603 Result_Cst); 604 AttemptToFoldSymbolOffsetDifference(Asm, Layout, Addrs, InSet, RHS_A, LHS_B, 605 Result_Cst); 606 AttemptToFoldSymbolOffsetDifference(Asm, Layout, Addrs, InSet, RHS_A, RHS_B, 607 Result_Cst); 608 } 609 610 // We can't represent the addition or subtraction of two symbols. 611 if ((LHS_A && RHS_A) || (LHS_B && RHS_B)) 612 return false; 613 614 // At this point, we have at most one additive symbol and one subtractive 615 // symbol -- find them. 616 const MCSymbolRefExpr *A = LHS_A ? LHS_A : RHS_A; 617 const MCSymbolRefExpr *B = LHS_B ? LHS_B : RHS_B; 618 619 // If we have a negated symbol, then we must have also have a non-negated 620 // symbol in order to encode the expression. 621 if (B && !A) 622 return false; 623 624 Res = MCValue::get(A, B, Result_Cst); 625 return true; 626} 627 628bool MCExpr::EvaluateAsRelocatable(MCValue &Res, 629 const MCAsmLayout *Layout) const { 630 MCAssembler *Assembler = Layout ? &Layout->getAssembler() : 0; 631 return EvaluateAsRelocatableImpl(Res, Assembler, Layout, 0, false); 632} 633 634bool MCExpr::EvaluateAsRelocatableImpl(MCValue &Res, 635 const MCAssembler *Asm, 636 const MCAsmLayout *Layout, 637 const SectionAddrMap *Addrs, 638 bool InSet) const { 639 ++stats::MCExprEvaluate; 640 641 switch (getKind()) { 642 case Target: 643 return cast<MCTargetExpr>(this)->EvaluateAsRelocatableImpl(Res, Layout); 644 645 case Constant: 646 Res = MCValue::get(cast<MCConstantExpr>(this)->getValue()); 647 return true; 648 649 case SymbolRef: { 650 const MCSymbolRefExpr *SRE = cast<MCSymbolRefExpr>(this); 651 const MCSymbol &Sym = SRE->getSymbol(); 652 const MCAsmInfo &MCAsmInfo = SRE->getMCAsmInfo(); 653 654 // Evaluate recursively if this is a variable. 655 if (Sym.isVariable()) { 656 if (Sym.getVariableValue()->EvaluateAsRelocatableImpl(Res, Asm, Layout, 657 Addrs, true)) { 658 const MCSymbolRefExpr *A = Res.getSymA(); 659 const MCSymbolRefExpr *B = Res.getSymB(); 660 661 if (MCAsmInfo.hasSubsectionsViaSymbols()) { 662 // FIXME: This is small hack. Given 663 // a = b + 4 664 // .long a 665 // the OS X assembler will completely drop the 4. We should probably 666 // include it in the relocation or produce an error if that is not 667 // possible. 668 if (!A && !B) 669 return true; 670 } else { 671 bool IsSymbol = A && A->getSymbol().isDefined(); 672 bool IsWeakRef = SRE->getKind() == MCSymbolRefExpr::VK_WEAKREF; 673 if (!IsSymbol && !IsWeakRef) 674 return true; 675 } 676 } 677 } 678 679 Res = MCValue::get(SRE, 0, 0); 680 return true; 681 } 682 683 case Unary: { 684 const MCUnaryExpr *AUE = cast<MCUnaryExpr>(this); 685 MCValue Value; 686 687 if (!AUE->getSubExpr()->EvaluateAsRelocatableImpl(Value, Asm, Layout, 688 Addrs, InSet)) 689 return false; 690 691 switch (AUE->getOpcode()) { 692 case MCUnaryExpr::LNot: 693 if (!Value.isAbsolute()) 694 return false; 695 Res = MCValue::get(!Value.getConstant()); 696 break; 697 case MCUnaryExpr::Minus: 698 /// -(a - b + const) ==> (b - a - const) 699 if (Value.getSymA() && !Value.getSymB()) 700 return false; 701 Res = MCValue::get(Value.getSymB(), Value.getSymA(), 702 -Value.getConstant()); 703 break; 704 case MCUnaryExpr::Not: 705 if (!Value.isAbsolute()) 706 return false; 707 Res = MCValue::get(~Value.getConstant()); 708 break; 709 case MCUnaryExpr::Plus: 710 Res = Value; 711 break; 712 } 713 714 return true; 715 } 716 717 case Binary: { 718 const MCBinaryExpr *ABE = cast<MCBinaryExpr>(this); 719 MCValue LHSValue, RHSValue; 720 721 if (!ABE->getLHS()->EvaluateAsRelocatableImpl(LHSValue, Asm, Layout, 722 Addrs, InSet) || 723 !ABE->getRHS()->EvaluateAsRelocatableImpl(RHSValue, Asm, Layout, 724 Addrs, InSet)) 725 return false; 726 727 // We only support a few operations on non-constant expressions, handle 728 // those first. 729 if (!LHSValue.isAbsolute() || !RHSValue.isAbsolute()) { 730 switch (ABE->getOpcode()) { 731 default: 732 return false; 733 case MCBinaryExpr::Sub: 734 // Negate RHS and add. 735 return EvaluateSymbolicAdd(Asm, Layout, Addrs, InSet, LHSValue, 736 RHSValue.getSymB(), RHSValue.getSymA(), 737 -RHSValue.getConstant(), 738 Res); 739 740 case MCBinaryExpr::Add: 741 return EvaluateSymbolicAdd(Asm, Layout, Addrs, InSet, LHSValue, 742 RHSValue.getSymA(), RHSValue.getSymB(), 743 RHSValue.getConstant(), 744 Res); 745 } 746 } 747 748 // FIXME: We need target hooks for the evaluation. It may be limited in 749 // width, and gas defines the result of comparisons and right shifts 750 // differently from Apple as. 751 int64_t LHS = LHSValue.getConstant(), RHS = RHSValue.getConstant(); 752 int64_t Result = 0; 753 switch (ABE->getOpcode()) { 754 case MCBinaryExpr::Add: Result = LHS + RHS; break; 755 case MCBinaryExpr::And: Result = LHS & RHS; break; 756 case MCBinaryExpr::Div: Result = LHS / RHS; break; 757 case MCBinaryExpr::EQ: Result = LHS == RHS; break; 758 case MCBinaryExpr::GT: Result = LHS > RHS; break; 759 case MCBinaryExpr::GTE: Result = LHS >= RHS; break; 760 case MCBinaryExpr::LAnd: Result = LHS && RHS; break; 761 case MCBinaryExpr::LOr: Result = LHS || RHS; break; 762 case MCBinaryExpr::LT: Result = LHS < RHS; break; 763 case MCBinaryExpr::LTE: Result = LHS <= RHS; break; 764 case MCBinaryExpr::Mod: Result = LHS % RHS; break; 765 case MCBinaryExpr::Mul: Result = LHS * RHS; break; 766 case MCBinaryExpr::NE: Result = LHS != RHS; break; 767 case MCBinaryExpr::Or: Result = LHS | RHS; break; 768 case MCBinaryExpr::Shl: Result = LHS << RHS; break; 769 case MCBinaryExpr::Shr: Result = LHS >> RHS; break; 770 case MCBinaryExpr::Sub: Result = LHS - RHS; break; 771 case MCBinaryExpr::Xor: Result = LHS ^ RHS; break; 772 } 773 774 Res = MCValue::get(Result); 775 return true; 776 } 777 } 778 779 llvm_unreachable("Invalid assembly expression kind!"); 780} 781 782const MCSection *MCExpr::FindAssociatedSection() const { 783 switch (getKind()) { 784 case Target: 785 // We never look through target specific expressions. 786 return cast<MCTargetExpr>(this)->FindAssociatedSection(); 787 788 case Constant: 789 return MCSymbol::AbsolutePseudoSection; 790 791 case SymbolRef: { 792 const MCSymbolRefExpr *SRE = cast<MCSymbolRefExpr>(this); 793 const MCSymbol &Sym = SRE->getSymbol(); 794 795 if (Sym.isDefined()) 796 return &Sym.getSection(); 797 798 return 0; 799 } 800 801 case Unary: 802 return cast<MCUnaryExpr>(this)->getSubExpr()->FindAssociatedSection(); 803 804 case Binary: { 805 const MCBinaryExpr *BE = cast<MCBinaryExpr>(this); 806 const MCSection *LHS_S = BE->getLHS()->FindAssociatedSection(); 807 const MCSection *RHS_S = BE->getRHS()->FindAssociatedSection(); 808 809 // If either section is absolute, return the other. 810 if (LHS_S == MCSymbol::AbsolutePseudoSection) 811 return RHS_S; 812 if (RHS_S == MCSymbol::AbsolutePseudoSection) 813 return LHS_S; 814 815 // Otherwise, return the first non-null section. 816 return LHS_S ? LHS_S : RHS_S; 817 } 818 } 819 820 llvm_unreachable("Invalid assembly expression kind!"); 821} 822