src/ld/passes/order.cpp

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  24
  25
  26 #include <stdint.h>
  27 #include <math.h>
  28 #include <unistd.h>
  29 #include <dlfcn.h>
  30 #include <mach/machine.h>
  31
  32 #include <vector>
  33 #include <map>
  34
  35 #include "ld.hpp"
  36 #include "order.h"
  37
  38 namespace ld {
  39 namespace passes {
  40 namespace order {
  41
  42 //
  43 // The purpose of this pass is to take the graph of all Atoms and produce an ordered
  44 // sequence of atoms.  The constraints are that: 1) all Atoms of the same Segment must
  45 // be contiguous, 2)  all Atoms of the same Section must be contigous, 3) Atoms specified
  46 // in an order are sequenced as in the order file and before Atoms not specified,
  47 // 4) Atoms in the same section from the same .o file should be contiguous and sequenced
  48 // in the same order they were in the .o file, 5) Atoms in the same Section but which came
  49 // from different .o files should be sequenced in the same order that the .o files
  50 // were passed to the linker (i.e. command line order).
  51 //
  52 // The way this is implemented is that the linker passes a "base ordinal" to each File
  53 // as it is constructed. Add each atom has an objectAddress() method. Then
  54 // sorting is just sorting by section, then by file ordinal, then by object address.
  55 //
  56 // If an -order_file is specified, it gets more complicated.  First, an override-ordinal map
  57 // is created.  It causes the sort routine to ignore the value returned by ordinal() and objectAddress()
  58 // and use the override value instead.  Next some Atoms must be laid out consecutively
  59 // (e.g. hand written assembly that does not end with return, but rather falls into
  60 // the next label).  This is modeled in via a kindNoneFollowOn fixup.  The use of
  61 // kindNoneFollowOn fixups produces "clusters" of atoms that must stay together.
  62 // If an order_file tries to move one atom, it may need to move a whole cluster.  The
  63 // algorithm to do this models clusters using two maps.  The "starts" maps maps any
  64 // atom in a cluster to the first Atom in the cluster.  The "nexts" maps an Atom in a
  65 // cluster to the next Atom in the cluster.  With this in place, while processing an
  66 // order_file, if any entry is in a cluster (in "starts" map), then the entire cluster is
  67 // given ordinal overrides.
  68 //
  69
  70 class Layout
  71 {
  72 public:
  73                                 Layout(const Options& opts, ld::Internal& state);
  74         void            doPass();
  75 private:
  76
  77         class Comparer {
  78         public:
  79                                         Comparer(const Layout& l) : _layout(l) {}
  80                 bool            operator()(const ld::Atom* left, const ld::Atom* right);
  81         private:
  82                 const Layout&   _layout;
  83         };
  84
  85         class CStringEquals {
  86         public:
  87                 bool operator()(const char* left, const char* right) const { return (strcmp(left, right) == 0); }
  88         };
  89         typedef __gnu_cxx::hash_map<const char*, const ld::Atom*, __gnu_cxx::hash<const char*>, CStringEquals> NameToAtom;
  90
  91         typedef std::map<const ld::Atom*, const ld::Atom*> AtomToAtom;
  92
  93         typedef std::map<const ld::Atom*, uint32_t> AtomToOrdinal;
  94
  95         const ld::Atom*         findAtom(const Options::OrderedSymbol& orderedSymbol);
  96         void                            buildNameTable();
  97         void                            buildFollowOnTables();
  98         void                            buildOrdinalOverrideMap();
  99         const ld::Atom*         follower(const ld::Atom* atom);
 100         static bool                     matchesObjectFile(const ld::Atom* atom, const char* objectFileLeafName);
 101                         bool            possibleToOrder(const ld::Internal::FinalSection*);
 102
 103         const Options&                                          _options;
 104         ld::Internal&                                           _state;
 105         AtomToAtom                                                      _followOnStarts;
 106         AtomToAtom                                                      _followOnNexts;
 107         NameToAtom                                                      _nameTable;
 108         std::vector<const ld::Atom*>            _nameCollisionAtoms;
 109         AtomToOrdinal                                           _ordinalOverrideMap;
 110         Comparer                                                        _comparer;
 111         bool                                                            _haveOrderFile;
 112
 113         static bool                                                     _s_log;
 114 };
 115
 116 bool Layout::_s_log = false;
 117
 118 Layout::Layout(const Options& opts, ld::Internal& state)
 119         : _options(opts), _state(state), _comparer(*this), _haveOrderFile(opts.orderedSymbolsCount() != 0)
 120 {
 121 }
 122
 123
 124 bool Layout::Comparer::operator()(const ld::Atom* left, const ld::Atom* right)
 125 {
 126         if ( left == right )
 127                 return false;
 128
 129         // magic section$start symbol always sorts to the start of its section
 130         if ( left->contentType() == ld::Atom::typeSectionStart )
 131                 return true;
 132         if ( right->contentType() == ld::Atom::typeSectionStart )
 133                 return false;
 134
 135         // if an -order_file is specified, then sorting is altered to sort those symbols first
 136         if ( _layout._haveOrderFile ) {
 137                 AtomToOrdinal::const_iterator leftPos  = _layout._ordinalOverrideMap.find(left);
 138                 AtomToOrdinal::const_iterator rightPos = _layout._ordinalOverrideMap.find(right);
 139                 AtomToOrdinal::const_iterator end = _layout._ordinalOverrideMap.end();
 140                 if ( leftPos != end ) {
 141                         if ( rightPos != end ) {
 142                                 // both left and right are overridden, so compare overridden ordinals
 143                                 return leftPos->second < rightPos->second;
 144                         }
 145                         else {
 146                                 // left is overridden and right is not, so left < right
 147                                 return true;
 148                         }
 149                 }
 150                 else {
 151                         if ( rightPos != end ) {
 152                                 // right is overridden and left is not, so right < left
 153                                 return false;
 154                         }
 155                         else {
 156                                 // neither are overridden,
 157                                 // fall into default sorting below
 158                         }
 159                 }
 160         }
 161
 162         // magic section$end symbol always sorts to the end of its section
 163         if ( left->contentType() == ld::Atom::typeSectionEnd )
 164                 return false;
 165         if ( right->contentType() == ld::Atom::typeSectionEnd )
 166                 return true;
 167
 168         // the __common section can have real or tentative definitions
 169         // we want the real ones to sort before tentative ones
 170         bool leftIsTent  =  (left->definition() == ld::Atom::definitionTentative);
 171         bool rightIsTent =  (right->definition() == ld::Atom::definitionTentative);
 172         if ( leftIsTent != rightIsTent )
 173                 return rightIsTent;
 174
 175 #if 0
 176         // initializers are auto sorted to start of section
 177         if ( !fInitializerSet.empty() ) {
 178                 bool leftFirst  = (fInitializerSet.count(left) != 0);
 179                 bool rightFirst = (fInitializerSet.count(right) != 0);
 180                 if ( leftFirst != rightFirst )
 181                         return leftFirst;
 182         }
 183
 184         // terminators are auto sorted to end of section
 185         if ( !fTerminatorSet.empty() ) {
 186                 bool leftLast  = (fTerminatorSet.count(left) != 0);
 187                 bool rightLast = (fTerminatorSet.count(right) != 0);
 188                 if ( leftLast != rightLast )
 189                         return rightLast;
 190         }
 191 #endif
 192
 193         // sort by .o order
 194         const ld::File* leftFile = left->file();
 195         const ld::File* rightFile = right->file();
 196         // <rdar://problem/10830126> properly sort if on file is NULL and the other is not
 197         ld::File::Ordinal leftFileOrdinal = (leftFile != NULL) ? leftFile->ordinal() : ld::File::Ordinal::NullOrdinal();
 198         ld::File::Ordinal rightFileOrdinal = (rightFile != NULL) ? rightFile->ordinal() : ld::File::Ordinal::NullOrdinal();
 199         if ( leftFileOrdinal != rightFileOrdinal )
 200                 return leftFileOrdinal< rightFileOrdinal;
 201
 202         // tentative defintions have no address in .o file, they are traditionally laid out by name
 203         if ( leftIsTent && rightIsTent )
 204                 return (strcmp(left->name(), right->name()) < 0);
 205
 206         // lastly sort by atom address
 207         int64_t addrDiff = left->objectAddress() - right->objectAddress();
 208         if ( addrDiff == 0 ) {
 209                 // have same address so one might be an alias, and aliases need to sort before target
 210                 bool leftIsAlias = left->isAlias();
 211                 bool rightIsAlias = right->isAlias();
 212                 if ( leftIsAlias != rightIsAlias )
 213                         return leftIsAlias;
 214
 215                 // both at same address, sort by name
 216                 return (strcmp(left->name(), right->name()) < 0);
 217         }
 218         return (addrDiff < 0);
 219 }
 220
 221 bool Layout::matchesObjectFile(const ld::Atom* atom, const char* objectFileLeafName)
 222 {
 223         if ( objectFileLeafName == NULL )
 224                 return true;
 225         const char* atomFullPath = atom->file()->path();
 226         const char* lastSlash = strrchr(atomFullPath, '/');
 227         if ( lastSlash != NULL ) {
 228                 if ( strcmp(&lastSlash[1], objectFileLeafName) == 0 )
 229                         return true;
 230         }
 231         else {
 232                 if ( strcmp(atomFullPath, objectFileLeafName) == 0 )
 233                         return true;
 234         }
 235         return false;
 236 }
 237
 238
 239 bool Layout::possibleToOrder(const ld::Internal::FinalSection* sect)
 240 {
 241         // atoms in only some sections can have order_file applied
 242         switch ( sect->type() ) {
 243                 case ld::Section::typeUnclassified:
 244                 case ld::Section::typeCode:
 245                 case ld::Section::typeZeroFill:
 246                         return true;
 247                 case ld::Section::typeImportProxies:
 248                         return false;
 249                 default:
 250                         // if section has command line aliases, then we must apply ordering so aliases layout before targets
 251                         if ( _options.haveCmdLineAliases() ) {
 252                                 for (std::vector<const ld::Atom*>::const_iterator ait=sect->atoms.begin(); ait != sect->atoms.end(); ++ait) {
 253                                         const ld::Atom* atom = *ait;
 254                                         if ( atom->isAlias() )
 255                                                 return true;
 256                                 }
 257                         }
 258                         break;
 259         }
 260         return false;
 261 }
 262
 263 void Layout::buildNameTable()
 264 {
 265         for (std::vector<ld::Internal::FinalSection*>::iterator sit=_state.sections.begin(); sit != _state.sections.end(); ++sit) {
 266                 ld::Internal::FinalSection* sect = *sit;
 267                 // some sections are not worth scanning for names
 268                 if ( ! possibleToOrder(sect) )
 269                         continue;
 270                 for (std::vector<const ld::Atom*>::iterator ait=sect->atoms.begin(); ait != sect->atoms.end(); ++ait) {
 271                         const ld::Atom* atom = *ait;
 272                         if ( atom->symbolTableInclusion() == ld::Atom::symbolTableIn ) {
 273                                 const char* name = atom->name();
 274                                 if ( name != NULL) {
 275                                         // static function or data
 276                                         NameToAtom::iterator pos = _nameTable.find(name);
 277                                         if ( pos == _nameTable.end() )
 278                                                 _nameTable[name] = atom;
 279                                         else {
 280                                                 const ld::Atom* existing = _nameTable[name];
 281                                                 if ( existing != NULL ) {
 282                                                         _nameCollisionAtoms.push_back(existing);
 283                                                         _nameTable[name] = NULL;        // collision, denote with NULL
 284                                                 }
 285                                                 _nameCollisionAtoms.push_back(atom);
 286                                         }
 287                                 }
 288                         }
 289                 }
 290         }
 291         if ( _s_log ) {
 292                 fprintf(stderr, "buildNameTable() _nameTable:\n");
 293                 for(NameToAtom::iterator it=_nameTable.begin(); it != _nameTable.end(); ++it)
 294                         fprintf(stderr, "  %p <- %s\n", it->second, it->first);
 295                 fprintf(stderr, "buildNameTable() _nameCollisionAtoms:\n");
 296                 for(std::vector<const ld::Atom*>::iterator it=_nameCollisionAtoms.begin(); it != _nameCollisionAtoms.end(); ++it)
 297                         fprintf(stderr, "  %p, %s\n", *it, (*it)->name());
 298         }
 299 }
 300
 301
 302 const ld::Atom* Layout::findAtom(const Options::OrderedSymbol& orderedSymbol)
 303 {
 304         // look for name in _nameTable
 305         NameToAtom::iterator pos = _nameTable.find(orderedSymbol.symbolName);
 306         if ( pos != _nameTable.end() ) {
 307                 if ( (pos->second != NULL) && matchesObjectFile(pos->second, orderedSymbol.objectFileName) ) {
 308                         //fprintf(stderr, "found %s in hash table\n", orderedSymbol.symbolName);
 309                         return pos->second;
 310                 }
 311                 if ( pos->second == NULL ) {
 312                         // name is in hash table, but atom is NULL, so that means there are duplicates, so we use super slow way
 313                         if ( ( orderedSymbol.objectFileName == NULL) && _options.printOrderFileStatistics() ) {
 314                                 warning("%s specified in order_file but it exists in multiple .o files. "
 315                                                 "Prefix symbol with .o filename in order_file to disambiguate", orderedSymbol.symbolName);
 316                         }
 317                         for (std::vector<const ld::Atom*>::iterator it=_nameCollisionAtoms.begin(); it != _nameCollisionAtoms.end(); it++) {
 318                                 const ld::Atom* atom = *it;
 319                                 if ( strcmp(atom->name(), orderedSymbol.symbolName) == 0 ) {
 320                                         if ( matchesObjectFile(atom, orderedSymbol.objectFileName) ) {
 321                                                 return atom;
 322                                         }
 323                                 }
 324                         }
 325                 }
 326         }
 327
 328         return NULL;
 329 }
 330
 331 const ld::Atom* Layout::follower(const ld::Atom* atom)
 332 {
 333         for (const ld::Atom* a = _followOnStarts[atom]; a != NULL; a = _followOnNexts[a]) {
 334                 assert(a != NULL);
 335                 if ( _followOnNexts[a] == atom ) {
 336                         return a;
 337                 }
 338         }
 339         // no follower, first in chain
 340         return NULL;
 341 }
 342
 343 void Layout::buildFollowOnTables()
 344 {
 345         // if no -order_file, then skip building follow on table
 346         if ( ! _haveOrderFile )
 347                 return;
 348
 349         // first make a pass to find all follow-on references and build start/next maps
 350         // which are a way to represent clusters of atoms that must layout together
 351         for (std::vector<ld::Internal::FinalSection*>::iterator sit=_state.sections.begin(); sit != _state.sections.end(); ++sit) {
 352                 ld::Internal::FinalSection* sect = *sit;
 353                 if ( !possibleToOrder(sect) )
 354                         continue;
 355                 for (std::vector<const ld::Atom*>::iterator ait=sect->atoms.begin(); ait != sect->atoms.end(); ++ait) {
 356                         const ld::Atom* atom = *ait;
 357                         for (ld::Fixup::iterator fit = atom->fixupsBegin(), end=atom->fixupsEnd(); fit != end; ++fit) {
 358                                 if ( fit->kind == ld::Fixup::kindNoneFollowOn ) {
 359                                         assert(fit->binding == ld::Fixup::bindingDirectlyBound);
 360                                         const ld::Atom* followOnAtom = fit->u.target;
 361                                         if ( _s_log ) fprintf(stderr, "ref %p %s -> %p %s\n", atom, atom->name(), followOnAtom, followOnAtom->name());
 362                                         assert(_followOnNexts.count(atom) == 0);
 363                                         _followOnNexts[atom] = followOnAtom;
 364                                         if ( _followOnStarts.count(atom) == 0 ) {
 365                                                 // first time atom has been seen, make it start of chain
 366                                                 _followOnStarts[atom] = atom;
 367                                                 if ( _s_log ) fprintf(stderr, "  start %s -> %s\n", atom->name(), atom->name());
 368                                         }
 369                                         if ( _followOnStarts.count(followOnAtom) == 0 ) {
 370                                                 // first time followOnAtom has been seen, make atom start of chain
 371                                                 _followOnStarts[followOnAtom] = _followOnStarts[atom];
 372                                                 if ( _s_log ) fprintf(stderr, "  start %s -> %s\n", followOnAtom->name(), _followOnStarts[atom]->name());
 373                                         }
 374                                         else {
 375                                                 if ( _followOnStarts[followOnAtom] == followOnAtom ) {
 376                                                         // followOnAtom atom already start of another chain, hook together
 377                                                         // and change all to use atom as start
 378                                                         const ld::Atom* a = followOnAtom;
 379                                                         while ( true ) {
 380                                                                 assert(_followOnStarts[a] == followOnAtom);
 381                                                                 _followOnStarts[a] = _followOnStarts[atom];
 382                                                                 if ( _s_log ) fprintf(stderr, "  adjust start for %s -> %s\n", a->name(), _followOnStarts[atom]->name());
 383                                                                 AtomToAtom::iterator pos = _followOnNexts.find(a);
 384                                                                 if ( pos != _followOnNexts.end() )
 385                                                                         a = pos->second;
 386                                                                 else
 387                                                                         break;
 388                                                         }
 389                                                 }
 390                                                 else {
 391                                                         // attempt to insert atom into existing followOn chain
 392                                                         const ld::Atom* curPrevToFollowOnAtom = this->follower(followOnAtom);
 393                                                         assert(curPrevToFollowOnAtom != NULL);
 394                                                         assert((atom->size() == 0) || (curPrevToFollowOnAtom->size() == 0));
 395                                                         if ( atom->size() == 0 ) {
 396                                                                 // insert alias into existing chain right before followOnAtom
 397                                                                 _followOnNexts[curPrevToFollowOnAtom] = atom;
 398                                                                 _followOnNexts[atom] = followOnAtom;
 399                                                                 _followOnStarts[atom] = _followOnStarts[followOnAtom];
 400                                                         }
 401                                                         else {
 402                                                                 // insert real atom into existing chain right before alias of followOnAtom
 403                                                                 const ld::Atom* curPrevPrevToFollowOn = this->follower(curPrevToFollowOnAtom);
 404                                                                 if ( curPrevPrevToFollowOn == NULL ) {
 405                                                                         // nothing previous, so make this a start of a new chain
 406                                                                         _followOnNexts[atom] = curPrevToFollowOnAtom;
 407                                                                         for (const ld::Atom* a = atom; a != NULL; a = _followOnNexts[a]) {
 408                                                                                 if ( _s_log ) fprintf(stderr, "  adjust start for %s -> %s\n", a->name(), atom->name());
 409                                                                                 _followOnStarts[a] = atom;
 410                                                                         }
 411                                                                 }
 412                                                                 else {
 413                                                                         // is previous, insert into existing chain before previous
 414                                                                         _followOnNexts[curPrevPrevToFollowOn] = atom;
 415                                                                         _followOnNexts[atom] = curPrevToFollowOnAtom;
 416                                                                         _followOnStarts[atom] = _followOnStarts[curPrevToFollowOnAtom];
 417                                                                 }
 418                                                         }
 419                                                 }
 420                                         }
 421                                 }
 422                         }
 423                 }
 424         }
 425
 426         if ( _s_log ) {
 427                 for(AtomToAtom::iterator it = _followOnStarts.begin(); it != _followOnStarts.end(); ++it)
 428                         fprintf(stderr, "start %s -> %s\n", it->first->name(), it->second->name());
 429
 430                 for(AtomToAtom::iterator it = _followOnNexts.begin(); it != _followOnNexts.end(); ++it)
 431                         fprintf(stderr, "next %s -> %s\n", it->first->name(), (it->second != NULL) ? it->second->name() : "null");
 432         }
 433 }
 434
 435
 436 class InSet
 437 {
 438 public:
 439         InSet(const std::set<const ld::Atom*>& theSet) : _set(theSet)  {}
 440
 441         bool operator()(const ld::Atom* atom) const {
 442                 return ( _set.count(atom) != 0 );
 443         }
 444 private:
 445         const std::set<const ld::Atom*>&  _set;
 446 };
 447
 448
 449 void Layout::buildOrdinalOverrideMap()
 450 {
 451         // if no -order_file, then skip building override map
 452         if ( ! _haveOrderFile )
 453                 return;
 454
 455         // build fast name->atom table
 456         this->buildNameTable();
 457
 458         // handle .o files that cannot have their atoms rearranged
 459         // with the start/next maps of follow-on atoms we can process the order file and produce override ordinals
 460         uint32_t index = 0;
 461         uint32_t matchCount = 0;
 462         std::set<const ld::Atom*> moveToData;
 463         for(Options::OrderedSymbolsIterator it = _options.orderedSymbolsBegin(); it != _options.orderedSymbolsEnd(); ++it) {
 464                 const ld::Atom* atom = this->findAtom(*it);
 465                 if ( atom != NULL ) {
 466                         // <rdar://problem/8612550> When order file used on data, turn ordered zero fill symbols into zero data
 467                         switch ( atom->section().type() ) {
 468                                 case ld::Section::typeZeroFill:
 469                                 case ld::Section::typeTentativeDefs:
 470                                         if ( atom->size() <= 512 )
 471                                                 moveToData.insert(atom);
 472                                         break;
 473                                 default:
 474                                         break;
 475                         }
 476
 477                         AtomToAtom::iterator start = _followOnStarts.find(atom);
 478                         if ( start != _followOnStarts.end() ) {
 479                                 // this symbol for the order file corresponds to an atom that is in a cluster that must lay out together
 480                                 for(const ld::Atom* nextAtom = start->second; nextAtom != NULL; nextAtom = _followOnNexts[nextAtom]) {
 481                                         AtomToOrdinal::iterator pos = _ordinalOverrideMap.find(nextAtom);
 482                                         if ( pos == _ordinalOverrideMap.end() ) {
 483                                                 _ordinalOverrideMap[nextAtom] = index++;
 484                                                 if (_s_log ) fprintf(stderr, "override ordinal %u assigned to %s in cluster from %s\n", index, nextAtom->name(), nextAtom->file()->path());
 485                                         }
 486                                         else {
 487                                                 if (_s_log ) fprintf(stderr, "could not order %s as %u because it was already laid out earlier by %s as %u\n",
 488                                                                                 atom->name(), index, _followOnStarts[atom]->name(), _ordinalOverrideMap[atom] );
 489                                         }
 490                                 }
 491                         }
 492                         else {
 493                                 _ordinalOverrideMap[atom] = index;
 494                                 if (_s_log ) fprintf(stderr, "override ordinal %u assigned to %s from %s\n", index, atom->name(), atom->file()->path());
 495                         }
 496                         ++matchCount;
 497                 }
 498                 else {
 499                         if ( _options.printOrderFileStatistics() ) {
 500                                 if ( it->objectFileName == NULL )
 501                                         warning("can't find match for order_file entry: %s", it->symbolName);
 502                                 else
 503                                         warning("can't find match for order_file entry: %s/%s", it->objectFileName, it->symbolName);
 504                         }
 505                 }
 506                  ++index;
 507         }
 508         if ( _options.printOrderFileStatistics() && (_options.orderedSymbolsCount() != matchCount) ) {
 509                 warning("only %u out of %lu order_file symbols were applicable", matchCount, _options.orderedSymbolsCount() );
 510         }
 511
 512
 513         // <rdar://problem/8612550> When order file used on data, turn ordered zero fill symbols into zeroed data
 514         if ( ! moveToData.empty() ) {
 515                 for (std::vector<ld::Internal::FinalSection*>::iterator sit=_state.sections.begin(); sit != _state.sections.end(); ++sit) {
 516                         ld::Internal::FinalSection* sect = *sit;
 517                         switch ( sect->type() ) {
 518                                 case ld::Section::typeZeroFill:
 519                                 case ld::Section::typeTentativeDefs:
 520                                         sect->atoms.erase(std::remove_if(sect->atoms.begin(), sect->atoms.end(), InSet(moveToData)), sect->atoms.end());
 521                                         break;
 522                                 case ld::Section::typeUnclassified:
 523                                         if ( (strcmp(sect->sectionName(), "__data") == 0) && (strcmp(sect->segmentName(), "__DATA") == 0) )
 524                                                 sect->atoms.insert(sect->atoms.end(), moveToData.begin(), moveToData.end());
 525                                         break;
 526                                 default:
 527                                         break;
 528                         }
 529                 }
 530         }
 531
 532 }
 533
 534 void Layout::doPass()
 535 {
 536         // handle .o files that cannot have their atoms rearranged
 537         this->buildFollowOnTables();
 538
 539         // assign new ordinal value to all ordered atoms
 540         this->buildOrdinalOverrideMap();
 541
 542         // sort atoms in each section
 543         for (std::vector<ld::Internal::FinalSection*>::iterator sit=_state.sections.begin(); sit != _state.sections.end(); ++sit) {
 544                 ld::Internal::FinalSection* sect = *sit;
 545                 std::sort(sect->atoms.begin(), sect->atoms.end(), _comparer);
 546         }
 547
 548         //fprintf(stderr, "Sorted atoms:\n");
 549         //for (std::vector<ld::Internal::FinalSection*>::iterator sit=_state.sections.begin(); sit != _state.sections.end(); ++sit) {
 550         //      ld::Internal::FinalSection* sect = *sit;
 551         //      for (std::vector<const ld::Atom*>::iterator ait=sect->atoms.begin(); ait != sect->atoms.end(); ++ait) {
 552         //              const ld::Atom* atom = *ait;
 553         //              fprintf(stderr, "\t%s\t%s\n", sect->sectionName(), atom->name());
 554         //      }
 555         //}
 556
 557 }
 558
 559
 560 void doPass(const Options& opts, ld::Internal& state)
 561 {
 562         Layout layout(opts, state);
 563         layout.doPass();
 564 }
 565
 566
 567 } // namespace order_file
 568 } // namespace passes
 569 } // namespace ld