1 //===-- llvm/Target/TargetLoweringObjectFile.cpp - Object File Info -------===// 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 // This file implements classes used to handle lowerings specific to common 11 // object file formats. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #include "llvm/Target/TargetLoweringObjectFile.h" 16 #include "llvm/Constants.h" 17 #include "llvm/DerivedTypes.h" 18 #include "llvm/GlobalVariable.h" 19 #include "llvm/Support/Mangler.h" 20 #include "llvm/Target/TargetMachine.h" 21 #include "llvm/Target/TargetData.h" 22 #include "llvm/Target/TargetOptions.h" 23 #include "llvm/ADT/StringExtras.h" 24 using namespace llvm; 25 26 //===----------------------------------------------------------------------===// 27 // Generic Code 28 //===----------------------------------------------------------------------===// 29 30 TargetLoweringObjectFile::TargetLoweringObjectFile() { 31 TextSection = 0; 32 DataSection = 0; 33 BSSSection_ = 0; 34 ReadOnlySection = 0; 35 TLSDataSection = 0; 36 TLSBSSSection = 0; 37 CStringSection_ = 0; 38 } 39 40 TargetLoweringObjectFile::~TargetLoweringObjectFile() { 41 } 42 43 static bool isSuitableForBSS(const GlobalVariable *GV) { 44 Constant *C = GV->getInitializer(); 45 46 // Must have zero initializer. 47 if (!C->isNullValue()) 48 return false; 49 50 // Leave constant zeros in readonly constant sections, so they can be shared. 51 if (GV->isConstant()) 52 return false; 53 54 // If the global has an explicit section specified, don't put it in BSS. 55 if (!GV->getSection().empty()) 56 return false; 57 58 // If -nozero-initialized-in-bss is specified, don't ever use BSS. 59 if (NoZerosInBSS) 60 return false; 61 62 // Otherwise, put it in BSS! 63 return true; 64 } 65 66 static bool isConstantString(const Constant *C) { 67 // First check: is we have constant array of i8 terminated with zero 68 const ConstantArray *CVA = dyn_cast<ConstantArray>(C); 69 // Check, if initializer is a null-terminated string 70 if (CVA && CVA->isCString()) 71 return true; 72 73 // Another possibility: [1 x i8] zeroinitializer 74 if (isa<ConstantAggregateZero>(C)) 75 if (const ArrayType *Ty = dyn_cast<ArrayType>(C->getType())) 76 return (Ty->getElementType() == Type::Int8Ty && 77 Ty->getNumElements() == 1); 78 79 return false; 80 } 81 82 static SectionKind::Kind SectionKindForGlobal(const GlobalValue *GV, 83 const TargetMachine &TM) { 84 Reloc::Model ReloModel = TM.getRelocationModel(); 85 86 // Early exit - functions should be always in text sections. 87 const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV); 88 if (GVar == 0) 89 return SectionKind::Text; 90 91 92 // Handle thread-local data first. 93 if (GVar->isThreadLocal()) { 94 if (isSuitableForBSS(GVar)) 95 return SectionKind::ThreadBSS; 96 return SectionKind::ThreadData; 97 } 98 99 // Variable can be easily put to BSS section. 100 if (isSuitableForBSS(GVar)) 101 return SectionKind::BSS; 102 103 Constant *C = GVar->getInitializer(); 104 105 // If the global is marked constant, we can put it into a mergable section, 106 // a mergable string section, or general .data if it contains relocations. 107 if (GVar->isConstant()) { 108 // If the initializer for the global contains something that requires a 109 // relocation, then we may have to drop this into a wriable data section 110 // even though it is marked const. 111 switch (C->getRelocationInfo()) { 112 default: llvm_unreachable("unknown relocation info kind"); 113 case Constant::NoRelocation: 114 // If initializer is a null-terminated string, put it in a "cstring" 115 // section if the target has it. 116 if (isConstantString(C)) 117 return SectionKind::MergeableCString; 118 119 // Otherwise, just drop it into a mergable constant section. If we have 120 // a section for this size, use it, otherwise use the arbitrary sized 121 // mergable section. 122 switch (TM.getTargetData()->getTypeAllocSize(C->getType())) { 123 case 4: return SectionKind::MergeableConst4; 124 case 8: return SectionKind::MergeableConst8; 125 case 16: return SectionKind::MergeableConst16; 126 default: return SectionKind::MergeableConst; 127 } 128 129 case Constant::LocalRelocation: 130 // In static relocation model, the linker will resolve all addresses, so 131 // the relocation entries will actually be constants by the time the app 132 // starts up. However, we can't put this into a mergable section, because 133 // the linker doesn't take relocations into consideration when it tries to 134 // merge entries in the section. 135 if (ReloModel == Reloc::Static) 136 return SectionKind::ReadOnly; 137 138 // Otherwise, the dynamic linker needs to fix it up, put it in the 139 // writable data.rel.local section. 140 return SectionKind::ReadOnlyWithRelLocal; 141 142 case Constant::GlobalRelocations: 143 // In static relocation model, the linker will resolve all addresses, so 144 // the relocation entries will actually be constants by the time the app 145 // starts up. However, we can't put this into a mergable section, because 146 // the linker doesn't take relocations into consideration when it tries to 147 // merge entries in the section. 148 if (ReloModel == Reloc::Static) 149 return SectionKind::ReadOnly; 150 151 // Otherwise, the dynamic linker needs to fix it up, put it in the 152 // writable data.rel section. 153 return SectionKind::ReadOnlyWithRel; 154 } 155 } 156 157 // Okay, this isn't a constant. If the initializer for the global is going 158 // to require a runtime relocation by the dynamic linker, put it into a more 159 // specific section to improve startup time of the app. This coalesces these 160 // globals together onto fewer pages, improving the locality of the dynamic 161 // linker. 162 if (ReloModel == Reloc::Static) 163 return SectionKind::DataNoRel; 164 165 switch (C->getRelocationInfo()) { 166 default: llvm_unreachable("unknown relocation info kind"); 167 case Constant::NoRelocation: 168 return SectionKind::DataNoRel; 169 case Constant::LocalRelocation: 170 return SectionKind::DataRelLocal; 171 case Constant::GlobalRelocations: 172 return SectionKind::DataRel; 173 } 174 } 175 176 /// SectionForGlobal - This method computes the appropriate section to emit 177 /// the specified global variable or function definition. This should not 178 /// be passed external (or available externally) globals. 179 const Section *TargetLoweringObjectFile:: 180 SectionForGlobal(const GlobalValue *GV, Mangler *Mang, 181 const TargetMachine &TM) const { 182 assert(!GV->isDeclaration() && !GV->hasAvailableExternallyLinkage() && 183 "Can only be used for global definitions"); 184 185 SectionKind::Kind GVKind = SectionKindForGlobal(GV, TM); 186 187 SectionKind Kind = SectionKind::get(GVKind, GV->isWeakForLinker(), 188 GV->hasSection()); 189 190 191 // Select section name. 192 if (GV->hasSection()) { 193 // If the target has special section hacks for specifically named globals, 194 // return them now. 195 if (const Section *TS = getSpecialCasedSectionGlobals(GV, Mang, Kind)) 196 return TS; 197 198 // If the target has magic semantics for certain section names, make sure to 199 // pick up the flags. This allows the user to write things with attribute 200 // section and still get the appropriate section flags printed. 201 GVKind = getKindForNamedSection(GV->getSection().c_str(), GVKind); 202 203 return getOrCreateSection(GV->getSection().c_str(), false, GVKind); 204 } 205 206 207 // Use default section depending on the 'type' of global 208 return SelectSectionForGlobal(GV, Kind, Mang, TM); 209 } 210 211 // Lame default implementation. Calculate the section name for global. 212 const Section* 213 TargetLoweringObjectFile::SelectSectionForGlobal(const GlobalValue *GV, 214 SectionKind Kind, 215 Mangler *Mang, 216 const TargetMachine &TM) const{ 217 assert(!Kind.isThreadLocal() && "Doesn't support TLS"); 218 219 if (Kind.isText()) 220 return getTextSection(); 221 222 if (Kind.isBSS() && BSSSection_ != 0) 223 return BSSSection_; 224 225 if (Kind.isReadOnly() && ReadOnlySection != 0) 226 return ReadOnlySection; 227 228 return getDataSection(); 229 } 230 231 /// getSectionForMergableConstant - Given a mergable constant with the 232 /// specified size and relocation information, return a section that it 233 /// should be placed in. 234 const Section * 235 TargetLoweringObjectFile:: 236 getSectionForMergeableConstant(SectionKind Kind) const { 237 if (Kind.isReadOnly() && ReadOnlySection != 0) 238 return ReadOnlySection; 239 240 return DataSection; 241 } 242 243 244 const Section *TargetLoweringObjectFile:: 245 getOrCreateSection(const char *Name, bool isDirective, 246 SectionKind::Kind Kind) const { 247 Section &S = Sections[Name]; 248 249 // This is newly-created section, set it up properly. 250 if (S.Name.empty()) { 251 S.Kind = SectionKind::get(Kind, false /*weak*/, !isDirective); 252 S.Name = Name; 253 } 254 255 return &S; 256 } 257 258 259 260 //===----------------------------------------------------------------------===// 261 // ELF 262 //===----------------------------------------------------------------------===// 263 264 TargetLoweringObjectFileELF::TargetLoweringObjectFileELF(bool atIsCommentChar, 265 bool HasCrazyBSS) 266 : AtIsCommentChar(atIsCommentChar) { 267 268 if (!HasCrazyBSS) 269 BSSSection_ = getOrCreateSection("\t.bss", true, SectionKind::BSS); 270 else 271 // PPC/Linux doesn't support the .bss directive, it needs .section .bss. 272 // FIXME: Does .section .bss work everywhere?? 273 BSSSection_ = getOrCreateSection("\t.bss", false, SectionKind::BSS); 274 275 276 TextSection = getOrCreateSection("\t.text", true, SectionKind::Text); 277 DataSection = getOrCreateSection("\t.data", true, SectionKind::DataRel); 278 ReadOnlySection = 279 getOrCreateSection("\t.rodata", false, SectionKind::ReadOnly); 280 TLSDataSection = 281 getOrCreateSection("\t.tdata", false, SectionKind::ThreadData); 282 CStringSection_ = getOrCreateSection("\t.rodata.str", true, 283 SectionKind::MergeableCString); 284 285 TLSBSSSection = getOrCreateSection("\t.tbss", false, SectionKind::ThreadBSS); 286 287 DataRelSection = getOrCreateSection("\t.data.rel", false, 288 SectionKind::DataRel); 289 DataRelLocalSection = getOrCreateSection("\t.data.rel.local", false, 290 SectionKind::DataRelLocal); 291 DataRelROSection = getOrCreateSection("\t.data.rel.ro", false, 292 SectionKind::ReadOnlyWithRel); 293 DataRelROLocalSection = 294 getOrCreateSection("\t.data.rel.ro.local", false, 295 SectionKind::ReadOnlyWithRelLocal); 296 297 MergeableConst4Section = getOrCreateSection(".rodata.cst4", false, 298 SectionKind::MergeableConst4); 299 MergeableConst8Section = getOrCreateSection(".rodata.cst8", false, 300 SectionKind::MergeableConst8); 301 MergeableConst16Section = getOrCreateSection(".rodata.cst16", false, 302 SectionKind::MergeableConst16); 303 } 304 305 306 SectionKind::Kind TargetLoweringObjectFileELF:: 307 getKindForNamedSection(const char *Name, SectionKind::Kind K) const { 308 if (Name[0] != '.') return K; 309 310 // Some lame default implementation based on some magic section names. 311 if (strncmp(Name, ".gnu.linkonce.b.", 16) == 0 || 312 strncmp(Name, ".llvm.linkonce.b.", 17) == 0 || 313 strncmp(Name, ".gnu.linkonce.sb.", 17) == 0 || 314 strncmp(Name, ".llvm.linkonce.sb.", 18) == 0) 315 return SectionKind::BSS; 316 317 if (strcmp(Name, ".tdata") == 0 || 318 strncmp(Name, ".tdata.", 7) == 0 || 319 strncmp(Name, ".gnu.linkonce.td.", 17) == 0 || 320 strncmp(Name, ".llvm.linkonce.td.", 18) == 0) 321 return SectionKind::ThreadData; 322 323 if (strcmp(Name, ".tbss") == 0 || 324 strncmp(Name, ".tbss.", 6) == 0 || 325 strncmp(Name, ".gnu.linkonce.tb.", 17) == 0 || 326 strncmp(Name, ".llvm.linkonce.tb.", 18) == 0) 327 return SectionKind::ThreadBSS; 328 329 return K; 330 } 331 332 void TargetLoweringObjectFileELF:: 333 getSectionFlagsAsString(SectionKind Kind, SmallVectorImpl<char> &Str) const { 334 Str.push_back(','); 335 Str.push_back('"'); 336 337 if (!Kind.isMetadata()) 338 Str.push_back('a'); 339 if (Kind.isText()) 340 Str.push_back('x'); 341 if (Kind.isWriteable()) 342 Str.push_back('w'); 343 if (Kind.isMergeableCString() || 344 Kind.isMergeableConst4() || 345 Kind.isMergeableConst8() || 346 Kind.isMergeableConst16()) 347 Str.push_back('M'); 348 if (Kind.isMergeableCString()) 349 Str.push_back('S'); 350 if (Kind.isThreadLocal()) 351 Str.push_back('T'); 352 353 Str.push_back('"'); 354 Str.push_back(','); 355 356 // If comment string is '@', e.g. as on ARM - use '%' instead 357 if (AtIsCommentChar) 358 Str.push_back('%'); 359 else 360 Str.push_back('@'); 361 362 const char *KindStr; 363 if (Kind.isBSS() || Kind.isThreadBSS()) 364 KindStr = "nobits"; 365 else 366 KindStr = "progbits"; 367 368 Str.append(KindStr, KindStr+strlen(KindStr)); 369 370 if (Kind.isMergeableCString()) { 371 // TODO: Eventually handle multiple byte character strings. For now, all 372 // mergable C strings are single byte. 373 Str.push_back(','); 374 Str.push_back('1'); 375 } else if (Kind.isMergeableConst4()) { 376 Str.push_back(','); 377 Str.push_back('4'); 378 } else if (Kind.isMergeableConst8()) { 379 Str.push_back(','); 380 Str.push_back('8'); 381 } else if (Kind.isMergeableConst16()) { 382 Str.push_back(','); 383 Str.push_back('1'); 384 Str.push_back('6'); 385 } 386 } 387 388 389 static const char *getSectionPrefixForUniqueGlobal(SectionKind Kind) { 390 if (Kind.isText()) return ".gnu.linkonce.t."; 391 if (Kind.isReadOnly()) return ".gnu.linkonce.r."; 392 393 if (Kind.isThreadData()) return ".gnu.linkonce.td."; 394 if (Kind.isThreadBSS()) return ".gnu.linkonce.tb."; 395 396 if (Kind.isBSS()) return ".gnu.linkonce.b."; 397 if (Kind.isDataNoRel()) return ".gnu.linkonce.d."; 398 if (Kind.isDataRelLocal()) return ".gnu.linkonce.d.rel.local."; 399 if (Kind.isDataRel()) return ".gnu.linkonce.d.rel."; 400 if (Kind.isReadOnlyWithRelLocal()) return ".gnu.linkonce.d.rel.ro.local."; 401 402 assert(Kind.isReadOnlyWithRel() && "Unknown section kind"); 403 return ".gnu.linkonce.d.rel.ro."; 404 } 405 406 const Section *TargetLoweringObjectFileELF:: 407 SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind, 408 Mangler *Mang, const TargetMachine &TM) const { 409 410 // If this global is linkonce/weak and the target handles this by emitting it 411 // into a 'uniqued' section name, create and return the section now. 412 if (Kind.isWeak()) { 413 const char *Prefix = getSectionPrefixForUniqueGlobal(Kind); 414 std::string Name = Mang->makeNameProper(GV->getNameStr()); 415 return getOrCreateSection((Prefix+Name).c_str(), false, Kind.getKind()); 416 } 417 418 if (Kind.isText()) return TextSection; 419 420 if (Kind.isMergeableCString()) { 421 assert(CStringSection_ && "Should have string section prefix"); 422 423 // We also need alignment here. 424 // FIXME: this is getting the alignment of the character, not the 425 // alignment of the global! 426 unsigned Align = 427 TM.getTargetData()->getPreferredAlignment(cast<GlobalVariable>(GV)); 428 429 std::string Name = CStringSection_->getName() + "1." + utostr(Align); 430 return getOrCreateSection(Name.c_str(), false, 431 SectionKind::MergeableCString); 432 } 433 434 if (Kind.isMergeableConst()) { 435 if (Kind.isMergeableConst4()) 436 return MergeableConst4Section; 437 if (Kind.isMergeableConst8()) 438 return MergeableConst8Section; 439 if (Kind.isMergeableConst16()) 440 return MergeableConst16Section; 441 return ReadOnlySection; // .const 442 } 443 444 if (Kind.isReadOnly()) return ReadOnlySection; 445 446 if (Kind.isThreadData()) return TLSDataSection; 447 if (Kind.isThreadBSS()) return TLSBSSSection; 448 449 if (Kind.isBSS()) return BSSSection_; 450 451 if (Kind.isDataNoRel()) return DataSection; 452 if (Kind.isDataRelLocal()) return DataRelLocalSection; 453 if (Kind.isDataRel()) return DataRelSection; 454 if (Kind.isReadOnlyWithRelLocal()) return DataRelROLocalSection; 455 456 assert(Kind.isReadOnlyWithRel() && "Unknown section kind"); 457 return DataRelROSection; 458 } 459 460 /// getSectionForMergeableConstant - Given a mergeable constant with the 461 /// specified size and relocation information, return a section that it 462 /// should be placed in. 463 const Section *TargetLoweringObjectFileELF:: 464 getSectionForMergeableConstant(SectionKind Kind) const { 465 if (Kind.isMergeableConst4()) 466 return MergeableConst4Section; 467 if (Kind.isMergeableConst8()) 468 return MergeableConst8Section; 469 if (Kind.isMergeableConst16()) 470 return MergeableConst16Section; 471 if (Kind.isReadOnly()) 472 return ReadOnlySection; 473 474 if (Kind.isReadOnlyWithRelLocal()) return DataRelROLocalSection; 475 assert(Kind.isReadOnlyWithRel() && "Unknown section kind"); 476 return DataRelROSection; 477 } 478 479 //===----------------------------------------------------------------------===// 480 // MachO 481 //===----------------------------------------------------------------------===// 482 483 TargetLoweringObjectFileMachO:: 484 TargetLoweringObjectFileMachO(const TargetMachine &TM) { 485 TextSection = getOrCreateSection("\t.text", true, SectionKind::Text); 486 DataSection = getOrCreateSection("\t.data", true, SectionKind::DataRel); 487 488 CStringSection_ = getOrCreateSection("\t.cstring", true, 489 SectionKind::MergeableCString); 490 FourByteConstantSection = getOrCreateSection("\t.literal4\n", true, 491 SectionKind::MergeableConst4); 492 EightByteConstantSection = getOrCreateSection("\t.literal8\n", true, 493 SectionKind::MergeableConst8); 494 495 // ld_classic doesn't support .literal16 in 32-bit mode, and ld64 falls back 496 // to using it in -static mode. 497 if (TM.getRelocationModel() != Reloc::Static && 498 TM.getTargetData()->getPointerSize() == 32) 499 SixteenByteConstantSection = 500 getOrCreateSection("\t.literal16\n", true, SectionKind::MergeableConst16); 501 else 502 SixteenByteConstantSection = 0; 503 504 ReadOnlySection = getOrCreateSection("\t.const", true, SectionKind::ReadOnly); 505 506 TextCoalSection = 507 getOrCreateSection("\t__TEXT,__textcoal_nt,coalesced,pure_instructions", 508 false, SectionKind::Text); 509 ConstTextCoalSection = getOrCreateSection("\t__TEXT,__const_coal,coalesced", 510 false, SectionKind::Text); 511 ConstDataCoalSection = getOrCreateSection("\t__DATA,__const_coal,coalesced", 512 false, SectionKind::Text); 513 ConstDataSection = getOrCreateSection("\t.const_data", true, 514 SectionKind::ReadOnlyWithRel); 515 DataCoalSection = getOrCreateSection("\t__DATA,__datacoal_nt,coalesced", 516 false, SectionKind::DataRel); 517 } 518 519 const Section *TargetLoweringObjectFileMachO:: 520 SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind, 521 Mangler *Mang, const TargetMachine &TM) const { 522 assert(!Kind.isThreadLocal() && "Darwin doesn't support TLS"); 523 524 if (Kind.isText()) 525 return Kind.isWeak() ? TextCoalSection : TextSection; 526 527 // If this is weak/linkonce, put this in a coalescable section, either in text 528 // or data depending on if it is writable. 529 if (Kind.isWeak()) { 530 if (Kind.isReadOnly()) 531 return ConstTextCoalSection; 532 return DataCoalSection; 533 } 534 535 // FIXME: Alignment check should be handled by section classifier. 536 if (Kind.isMergeableCString()) { 537 Constant *C = cast<GlobalVariable>(GV)->getInitializer(); 538 const Type *Ty = cast<ArrayType>(C->getType())->getElementType(); 539 const TargetData &TD = *TM.getTargetData(); 540 unsigned Size = TD.getTypeAllocSize(Ty); 541 if (Size) { 542 unsigned Align = TD.getPreferredAlignment(cast<GlobalVariable>(GV)); 543 if (Align <= 32) 544 return CStringSection_; 545 } 546 547 return ReadOnlySection; 548 } 549 550 if (Kind.isMergeableConst()) { 551 if (Kind.isMergeableConst4()) 552 return FourByteConstantSection; 553 if (Kind.isMergeableConst8()) 554 return EightByteConstantSection; 555 if (Kind.isMergeableConst16() && SixteenByteConstantSection) 556 return SixteenByteConstantSection; 557 return ReadOnlySection; // .const 558 } 559 560 // FIXME: ROData -> const in -static mode that is relocatable but they happen 561 // by the static linker. Why not mergeable? 562 if (Kind.isReadOnly()) 563 return ReadOnlySection; 564 565 // If this is marked const, put it into a const section. But if the dynamic 566 // linker needs to write to it, put it in the data segment. 567 if (Kind.isReadOnlyWithRel()) 568 return ConstDataSection; 569 570 // Otherwise, just drop the variable in the normal data section. 571 return DataSection; 572 } 573 574 const Section * 575 TargetLoweringObjectFileMachO:: 576 getSectionForMergeableConstant(SectionKind Kind) const { 577 // If this constant requires a relocation, we have to put it in the data 578 // segment, not in the text segment. 579 if (Kind.isDataRel()) 580 return ConstDataSection; 581 582 if (Kind.isMergeableConst4()) 583 return FourByteConstantSection; 584 if (Kind.isMergeableConst8()) 585 return EightByteConstantSection; 586 if (Kind.isMergeableConst16() && SixteenByteConstantSection) 587 return SixteenByteConstantSection; 588 return ReadOnlySection; // .const 589 } 590 591 //===----------------------------------------------------------------------===// 592 // COFF 593 //===----------------------------------------------------------------------===// 594 595 TargetLoweringObjectFileCOFF::TargetLoweringObjectFileCOFF() { 596 TextSection = getOrCreateSection("\t.text", true, SectionKind::Text); 597 DataSection = getOrCreateSection("\t.data", true, SectionKind::DataRel); 598 } 599 600 void TargetLoweringObjectFileCOFF:: 601 getSectionFlagsAsString(SectionKind Kind, SmallVectorImpl<char> &Str) const { 602 // FIXME: Inefficient. 603 std::string Res = ",\""; 604 if (Kind.isText()) 605 Res += 'x'; 606 if (Kind.isWriteable()) 607 Res += 'w'; 608 Res += "\""; 609 610 Str.append(Res.begin(), Res.end()); 611 } 612 613 static const char *getCOFFSectionPrefixForUniqueGlobal(SectionKind Kind) { 614 if (Kind.isText()) 615 return ".text$linkonce"; 616 if (Kind.isWriteable()) 617 return ".data$linkonce"; 618 return ".rdata$linkonce"; 619 } 620 621 622 const Section *TargetLoweringObjectFileCOFF:: 623 SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind, 624 Mangler *Mang, const TargetMachine &TM) const { 625 assert(!Kind.isThreadLocal() && "Doesn't support TLS"); 626 627 // If this global is linkonce/weak and the target handles this by emitting it 628 // into a 'uniqued' section name, create and return the section now. 629 if (Kind.isWeak()) { 630 const char *Prefix = getCOFFSectionPrefixForUniqueGlobal(Kind); 631 // FIXME: Use mangler interface (PR4584). 632 std::string Name = Prefix+GV->getNameStr(); 633 return getOrCreateSection(Name.c_str(), false, Kind.getKind()); 634 } 635 636 if (Kind.isText()) 637 return getTextSection(); 638 639 if (Kind.isBSS()) 640 if (const Section *S = BSSSection_) 641 return S; 642 643 if (Kind.isReadOnly() && ReadOnlySection != 0) 644 return ReadOnlySection; 645 646 return getDataSection(); 647 } 648 649