lib/CompilerDriver/CompilationGraph.cpp

   1 //===--- CompilationGraph.cpp - The LLVM Compiler Driver --------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open
   6 // Source License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 //  Compilation graph - implementation.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/CompilerDriver/BuiltinOptions.h"
  15 #include "llvm/CompilerDriver/CompilationGraph.h"
  16 #include "llvm/CompilerDriver/Error.h"
  17
  18 #include "llvm/ADT/STLExtras.h"
  19 #include "llvm/Support/DOTGraphTraits.h"
  20 #include "llvm/Support/GraphWriter.h"
  21 #include "llvm/Support/raw_ostream.h"
  22
  23 #include <algorithm>
  24 #include <cstring>
  25 #include <iterator>
  26 #include <limits>
  27 #include <queue>
  28
  29 using namespace llvm;
  30 using namespace llvmc;
  31
  32 namespace llvmc {
  33
  34   const std::string* LanguageMap::GetLanguage(const sys::Path& File) const {
  35     // Remove the '.'.
  36     StringRef suf = sys::path::extension(File.str()).substr(1);
  37     LanguageMap::const_iterator Lang =
  38       this->find(suf.empty() ? "*empty*" : suf);
  39     if (Lang == this->end()) {
  40       PrintError("File '" + File.str() + "' has unknown suffix '"
  41                  + suf.str() + '\'');
  42       return 0;
  43     }
  44     return &Lang->second;
  45   }
  46 }
  47
  48 namespace {
  49
  50   /// ChooseEdge - Return the edge with the maximum weight. Returns 0 on error.
  51   template <class C>
  52   const Edge* ChooseEdge(const C& EdgesContainer,
  53                          const InputLanguagesSet& InLangs,
  54                          const std::string& NodeName = "root") {
  55     const Edge* MaxEdge = 0;
  56     int MaxWeight = 0;
  57     bool SingleMax = true;
  58
  59     // TODO: fix calculation of SingleMax.
  60     for (typename C::const_iterator B = EdgesContainer.begin(),
  61            E = EdgesContainer.end(); B != E; ++B) {
  62       const Edge* e = B->getPtr();
  63       int EW = e->Weight(InLangs);
  64       if (EW < 0) {
  65         // (error) invocation in TableGen -> we don't need to print an error
  66         // message.
  67         return 0;
  68       }
  69       if (EW > MaxWeight) {
  70         MaxEdge = e;
  71         MaxWeight = EW;
  72         SingleMax = true;
  73       } else if (EW == MaxWeight) {
  74         SingleMax = false;
  75       }
  76     }
  77
  78     if (!SingleMax) {
  79       PrintError("Node " + NodeName + ": multiple maximal outward edges found!"
  80                  " Most probably a specification error.");
  81       return 0;
  82     }
  83     if (!MaxEdge) {
  84       PrintError("Node " + NodeName + ": no maximal outward edge found!"
  85                  " Most probably a specification error.");
  86       return 0;
  87     }
  88     return MaxEdge;
  89   }
  90
  91 }
  92
  93 void Node::AddEdge(Edge* Edg) {
  94   // If there already was an edge between two nodes, modify it instead
  95   // of adding a new edge.
  96   const std::string& ToolName = Edg->ToolName();
  97   for (container_type::iterator B = OutEdges.begin(), E = OutEdges.end();
  98        B != E; ++B) {
  99     if ((*B)->ToolName() == ToolName) {
 100       llvm::IntrusiveRefCntPtr<Edge>(Edg).swap(*B);
 101       return;
 102     }
 103   }
 104   OutEdges.push_back(llvm::IntrusiveRefCntPtr<Edge>(Edg));
 105 }
 106
 107 CompilationGraph::CompilationGraph() {
 108   NodesMap["root"] = Node(this);
 109 }
 110
 111 Node* CompilationGraph::getNode(const std::string& ToolName) {
 112   nodes_map_type::iterator I = NodesMap.find(ToolName);
 113   if (I == NodesMap.end()) {
 114     PrintError("Node " + ToolName + " is not in the graph");
 115     return 0;
 116   }
 117   return &I->second;
 118 }
 119
 120 const Node* CompilationGraph::getNode(const std::string& ToolName) const {
 121   nodes_map_type::const_iterator I = NodesMap.find(ToolName);
 122   if (I == NodesMap.end()) {
 123     PrintError("Node " + ToolName + " is not in the graph!");
 124     return 0;
 125   }
 126   return &I->second;
 127 }
 128
 129 // Find the tools list corresponding to the given language name.
 130 const CompilationGraph::tools_vector_type*
 131 CompilationGraph::getToolsVector(const std::string& LangName) const
 132 {
 133   tools_map_type::const_iterator I = ToolsMap.find(LangName);
 134   if (I == ToolsMap.end()) {
 135     PrintError("No tool corresponding to the language " + LangName + " found");
 136     return 0;
 137   }
 138   return &I->second;
 139 }
 140
 141 void CompilationGraph::insertNode(Tool* V) {
 142   if (NodesMap.count(V->Name()) == 0)
 143     NodesMap[V->Name()] = Node(this, V);
 144 }
 145
 146 int CompilationGraph::insertEdge(const std::string& A, Edge* Edg) {
 147   Node* B = getNode(Edg->ToolName());
 148   if (B == 0)
 149     return 1;
 150
 151   if (A == "root") {
 152     const char** InLangs = B->ToolPtr->InputLanguages();
 153     for (;*InLangs; ++InLangs)
 154       ToolsMap[*InLangs].push_back(IntrusiveRefCntPtr<Edge>(Edg));
 155     NodesMap["root"].AddEdge(Edg);
 156   }
 157   else {
 158     Node* N = getNode(A);
 159     if (N == 0)
 160       return 1;
 161
 162     N->AddEdge(Edg);
 163   }
 164   // Increase the inward edge counter.
 165   B->IncrInEdges();
 166
 167   return 0;
 168 }
 169
 170 // Pass input file through the chain until we bump into a Join node or
 171 // a node that says that it is the last.
 172 int CompilationGraph::PassThroughGraph (const sys::Path& InFile,
 173                                         const Node* StartNode,
 174                                         const InputLanguagesSet& InLangs,
 175                                         const sys::Path& TempDir,
 176                                         const LanguageMap& LangMap) const {
 177   sys::Path In = InFile;
 178   const Node* CurNode = StartNode;
 179
 180   while(true) {
 181     Tool* CurTool = CurNode->ToolPtr.getPtr();
 182
 183     if (CurTool->IsJoin()) {
 184       JoinTool& JT = static_cast<JoinTool&>(*CurTool);
 185       JT.AddToJoinList(In);
 186       break;
 187     }
 188
 189     Action CurAction;
 190     if (int ret = CurTool->GenerateAction(CurAction, In, CurNode->HasChildren(),
 191                                           TempDir, InLangs, LangMap)) {
 192       return ret;
 193     }
 194
 195     if (int ret = CurAction.Execute())
 196       return ret;
 197
 198     if (CurAction.StopCompilation())
 199       return 0;
 200
 201     const Edge* Edg = ChooseEdge(CurNode->OutEdges, InLangs, CurNode->Name());
 202     if (Edg == 0)
 203       return 1;
 204
 205     CurNode = getNode(Edg->ToolName());
 206     if (CurNode == 0)
 207       return 1;
 208
 209     In = CurAction.OutFile();
 210   }
 211
 212   return 0;
 213 }
 214
 215 // Find the head of the toolchain corresponding to the given file.
 216 // Also, insert an input language into InLangs.
 217 const Node* CompilationGraph::
 218 FindToolChain(const sys::Path& In, const std::string* ForceLanguage,
 219               InputLanguagesSet& InLangs, const LanguageMap& LangMap) const {
 220
 221   // Determine the input language.
 222   const std::string* InLang = (ForceLanguage ? ForceLanguage
 223                                : LangMap.GetLanguage(In));
 224   if (InLang == 0)
 225     return 0;
 226   const std::string& InLanguage = *InLang;
 227
 228   // Add the current input language to the input language set.
 229   InLangs.insert(InLanguage);
 230
 231   // Find the toolchain for the input language.
 232   const tools_vector_type* pTV = getToolsVector(InLanguage);
 233   if (pTV == 0)
 234     return 0;
 235
 236   const tools_vector_type& TV = *pTV;
 237   if (TV.empty()) {
 238     PrintError("No toolchain corresponding to language "
 239                + InLanguage + " found");
 240     return 0;
 241   }
 242
 243   const Edge* Edg = ChooseEdge(TV, InLangs);
 244   if (Edg == 0)
 245     return 0;
 246
 247   return getNode(Edg->ToolName());
 248 }
 249
 250 // Helper function used by Build().
 251 // Traverses initial portions of the toolchains (up to the first Join node).
 252 // This function is also responsible for handling the -x option.
 253 int CompilationGraph::BuildInitial (InputLanguagesSet& InLangs,
 254                                     const sys::Path& TempDir,
 255                                     const LanguageMap& LangMap) {
 256   // This is related to -x option handling.
 257   cl::list<std::string>::const_iterator xIter = Languages.begin(),
 258     xBegin = xIter, xEnd = Languages.end();
 259   bool xEmpty = true;
 260   const std::string* xLanguage = 0;
 261   unsigned xPos = 0, xPosNext = 0, filePos = 0;
 262
 263   if (xIter != xEnd) {
 264     xEmpty = false;
 265     xPos = Languages.getPosition(xIter - xBegin);
 266     cl::list<std::string>::const_iterator xNext = llvm::next(xIter);
 267     xPosNext = (xNext == xEnd) ? std::numeric_limits<unsigned>::max()
 268       : Languages.getPosition(xNext - xBegin);
 269     xLanguage = (*xIter == "none") ? 0 : &(*xIter);
 270   }
 271
 272   // For each input file:
 273   for (cl::list<std::string>::const_iterator B = InputFilenames.begin(),
 274          CB = B, E = InputFilenames.end(); B != E; ++B) {
 275     sys::Path In = sys::Path(*B);
 276
 277     // Code for handling the -x option.
 278     // Output: std::string* xLanguage (can be NULL).
 279     if (!xEmpty) {
 280       filePos = InputFilenames.getPosition(B - CB);
 281
 282       if (xPos < filePos) {
 283         if (filePos < xPosNext) {
 284           xLanguage = (*xIter == "none") ? 0 : &(*xIter);
 285         }
 286         else { // filePos >= xPosNext
 287           // Skip xIters while filePos > xPosNext
 288           while (filePos > xPosNext) {
 289             ++xIter;
 290             xPos = xPosNext;
 291
 292             cl::list<std::string>::const_iterator xNext = llvm::next(xIter);
 293             if (xNext == xEnd)
 294               xPosNext = std::numeric_limits<unsigned>::max();
 295             else
 296               xPosNext = Languages.getPosition(xNext - xBegin);
 297             xLanguage = (*xIter == "none") ? 0 : &(*xIter);
 298           }
 299         }
 300       }
 301     }
 302
 303     // Find the toolchain corresponding to this file.
 304     const Node* N = FindToolChain(In, xLanguage, InLangs, LangMap);
 305     if (N == 0)
 306       return 1;
 307     // Pass file through the chain starting at head.
 308     if (int ret = PassThroughGraph(In, N, InLangs, TempDir, LangMap))
 309       return ret;
 310   }
 311
 312   return 0;
 313 }
 314
 315 // Sort the nodes in topological order.
 316 int CompilationGraph::TopologicalSort(std::vector<const Node*>& Out) {
 317   std::queue<const Node*> Q;
 318
 319   Node* Root = getNode("root");
 320   if (Root == 0)
 321     return 1;
 322
 323   Q.push(Root);
 324
 325   while (!Q.empty()) {
 326     const Node* A = Q.front();
 327     Q.pop();
 328     Out.push_back(A);
 329     for (Node::const_iterator EB = A->EdgesBegin(), EE = A->EdgesEnd();
 330          EB != EE; ++EB) {
 331       Node* B = getNode((*EB)->ToolName());
 332       if (B == 0)
 333         return 1;
 334
 335       B->DecrInEdges();
 336       if (B->HasNoInEdges())
 337         Q.push(B);
 338     }
 339   }
 340
 341   return 0;
 342 }
 343
 344 namespace {
 345   bool NotJoinNode(const Node* N) {
 346     return N->ToolPtr ? !N->ToolPtr->IsJoin() : true;
 347   }
 348 }
 349
 350 // Call TopologicalSort and filter the resulting list to include
 351 // only Join nodes.
 352 int CompilationGraph::
 353 TopologicalSortFilterJoinNodes(std::vector<const Node*>& Out) {
 354   std::vector<const Node*> TopSorted;
 355   if (int ret = TopologicalSort(TopSorted))
 356     return ret;
 357   std::remove_copy_if(TopSorted.begin(), TopSorted.end(),
 358                       std::back_inserter(Out), NotJoinNode);
 359
 360   return 0;
 361 }
 362
 363 int CompilationGraph::Build (const sys::Path& TempDir,
 364                              const LanguageMap& LangMap) {
 365   InputLanguagesSet InLangs;
 366   bool WasSomeActionGenerated = !InputFilenames.empty();
 367
 368   // Traverse initial parts of the toolchains and fill in InLangs.
 369   if (int ret = BuildInitial(InLangs, TempDir, LangMap))
 370     return ret;
 371
 372   std::vector<const Node*> JTV;
 373   if (int ret = TopologicalSortFilterJoinNodes(JTV))
 374     return ret;
 375
 376   // For all join nodes in topological order:
 377   for (std::vector<const Node*>::iterator B = JTV.begin(), E = JTV.end();
 378        B != E; ++B) {
 379
 380     const Node* CurNode = *B;
 381     JoinTool* JT = &static_cast<JoinTool&>(*CurNode->ToolPtr.getPtr());
 382
 383     // Are there any files in the join list?
 384     if (JT->JoinListEmpty() && !(JT->WorksOnEmpty() && InputFilenames.empty()))
 385       continue;
 386
 387     WasSomeActionGenerated = true;
 388     Action CurAction;
 389     if (int ret = JT->GenerateAction(CurAction, CurNode->HasChildren(),
 390                                      TempDir, InLangs, LangMap)) {
 391       return ret;
 392     }
 393
 394     if (int ret = CurAction.Execute())
 395       return ret;
 396
 397     if (CurAction.StopCompilation())
 398       return 0;
 399
 400     const Edge* Edg = ChooseEdge(CurNode->OutEdges, InLangs, CurNode->Name());
 401     if (Edg == 0)
 402       return 1;
 403
 404     const Node* NextNode = getNode(Edg->ToolName());
 405     if (NextNode == 0)
 406       return 1;
 407
 408     if (int ret = PassThroughGraph(sys::Path(CurAction.OutFile()), NextNode,
 409                                    InLangs, TempDir, LangMap)) {
 410       return ret;
 411     }
 412   }
 413
 414   if (!WasSomeActionGenerated) {
 415     PrintError("no input files");
 416     return 1;
 417   }
 418
 419   return 0;
 420 }
 421
 422 int CompilationGraph::CheckLanguageNames() const {
 423   int ret = 0;
 424
 425   // Check that names for output and input languages on all edges do match.
 426   for (const_nodes_iterator B = this->NodesMap.begin(),
 427          E = this->NodesMap.end(); B != E; ++B) {
 428
 429     const Node & N1 = B->second;
 430     if (N1.ToolPtr) {
 431       for (Node::const_iterator EB = N1.EdgesBegin(), EE = N1.EdgesEnd();
 432            EB != EE; ++EB) {
 433         const Node* N2 = this->getNode((*EB)->ToolName());
 434         if (N2 == 0)
 435           return 1;
 436
 437         if (!N2->ToolPtr) {
 438           ++ret;
 439           errs() << "Error: there is an edge from '" << N1.ToolPtr->Name()
 440                  << "' back to the root!\n\n";
 441           continue;
 442         }
 443
 444         const char** OutLangs = N1.ToolPtr->OutputLanguages();
 445         const char** InLangs = N2->ToolPtr->InputLanguages();
 446         bool eq = false;
 447         const char* OutLang = 0;
 448         for (;*OutLangs; ++OutLangs) {
 449           OutLang = *OutLangs;
 450           for (;*InLangs; ++InLangs) {
 451             if (std::strcmp(OutLang, *InLangs) == 0) {
 452               eq = true;
 453               break;
 454             }
 455           }
 456         }
 457
 458         if (!eq) {
 459           ++ret;
 460           errs() << "Error: Output->input language mismatch in the edge '"
 461                  << N1.ToolPtr->Name() << "' -> '" << N2->ToolPtr->Name()
 462                  << "'!\n"
 463                  << "Expected one of { ";
 464
 465           InLangs = N2->ToolPtr->InputLanguages();
 466           for (;*InLangs; ++InLangs) {
 467             errs() << '\'' << *InLangs << (*(InLangs+1) ? "', " : "'");
 468           }
 469
 470           errs() << " }, but got '" << OutLang << "'!\n\n";
 471         }
 472
 473       }
 474     }
 475   }
 476
 477   return ret;
 478 }
 479
 480 int CompilationGraph::CheckMultipleDefaultEdges() const {
 481   int ret = 0;
 482   InputLanguagesSet Dummy;
 483
 484   // For all nodes, just iterate over the outgoing edges and check if there is
 485   // more than one edge with maximum weight.
 486   for (const_nodes_iterator B = this->NodesMap.begin(),
 487          E = this->NodesMap.end(); B != E; ++B) {
 488     const Node& N = B->second;
 489     int MaxWeight = -1024;
 490
 491     // Ignore the root node.
 492     if (!N.ToolPtr)
 493       continue;
 494
 495     for (Node::const_iterator EB = N.EdgesBegin(), EE = N.EdgesEnd();
 496          EB != EE; ++EB) {
 497       int EdgeWeight = (*EB)->Weight(Dummy);
 498       if (EdgeWeight > MaxWeight) {
 499         MaxWeight = EdgeWeight;
 500       }
 501       else if (EdgeWeight == MaxWeight) {
 502         ++ret;
 503         errs() << "Error: there are multiple maximal edges stemming from the '"
 504                << N.ToolPtr->Name() << "' node!\n\n";
 505         break;
 506       }
 507     }
 508   }
 509
 510   return ret;
 511 }
 512
 513 int CompilationGraph::CheckCycles() {
 514   unsigned deleted = 0;
 515   std::queue<Node*> Q;
 516
 517   Node* Root = getNode("root");
 518   if (Root == 0)
 519     return 1;
 520
 521   Q.push(Root);
 522
 523   // Try to delete all nodes that have no ingoing edges, starting from the
 524   // root. If there are any nodes left after this operation, then we have a
 525   // cycle. This relies on '--check-graph' not performing the topological sort.
 526   while (!Q.empty()) {
 527     Node* A = Q.front();
 528     Q.pop();
 529     ++deleted;
 530
 531     for (Node::iterator EB = A->EdgesBegin(), EE = A->EdgesEnd();
 532          EB != EE; ++EB) {
 533       Node* B = getNode((*EB)->ToolName());
 534       if (B == 0)
 535         return 1;
 536
 537       B->DecrInEdges();
 538       if (B->HasNoInEdges())
 539         Q.push(B);
 540     }
 541   }
 542
 543   if (deleted != NodesMap.size()) {
 544     errs() << "Error: there are cycles in the compilation graph!\n"
 545            << "Try inspecting the diagram produced by "
 546            << "'llvmc --view-graph'.\n\n";
 547     return 1;
 548   }
 549
 550   return 0;
 551 }
 552
 553 int CompilationGraph::Check () {
 554   // We try to catch as many errors as we can in one go.
 555   int errs = 0;
 556   int ret = 0;
 557
 558   // Check that output/input language names match.
 559   ret = this->CheckLanguageNames();
 560   if (ret < 0)
 561     return 1;
 562   errs += ret;
 563
 564   // Check for multiple default edges.
 565   ret = this->CheckMultipleDefaultEdges();
 566   if (ret < 0)
 567     return 1;
 568   errs += ret;
 569
 570   // Check for cycles.
 571   ret = this->CheckCycles();
 572   if (ret < 0)
 573     return 1;
 574   errs += ret;
 575
 576   return errs;
 577 }
 578
 579 // Code related to graph visualization.
 580
 581 namespace {
 582
 583 std::string SquashStrArray (const char** StrArr) {
 584   std::string ret;
 585
 586   for (; *StrArr; ++StrArr) {
 587     if (*(StrArr + 1)) {
 588       ret += *StrArr;
 589       ret +=  ", ";
 590     }
 591     else {
 592       ret += *StrArr;
 593     }
 594   }
 595
 596   return ret;
 597 }
 598
 599 } // End anonymous namespace.
 600
 601 namespace llvm {
 602   template <>
 603   struct DOTGraphTraits<llvmc::CompilationGraph*>
 604     : public DefaultDOTGraphTraits
 605   {
 606     DOTGraphTraits (bool isSimple=false) : DefaultDOTGraphTraits(isSimple) {}
 607
 608     template<typename GraphType>
 609     static std::string getNodeLabel(const Node* N, const GraphType&)
 610     {
 611       if (N->ToolPtr)
 612         if (N->ToolPtr->IsJoin())
 613           return N->Name() + "\n (join" +
 614             (N->HasChildren() ? ")"
 615              : std::string(": ") +
 616              SquashStrArray(N->ToolPtr->OutputLanguages()) + ')');
 617         else
 618           return N->Name();
 619       else
 620         return "root";
 621     }
 622
 623     template<typename EdgeIter>
 624     static std::string getEdgeSourceLabel(const Node* N, EdgeIter I) {
 625       if (N->ToolPtr) {
 626         return SquashStrArray(N->ToolPtr->OutputLanguages());
 627       }
 628       else {
 629         return SquashStrArray(I->ToolPtr->InputLanguages());
 630       }
 631     }
 632   };
 633
 634 } // End namespace llvm
 635
 636 int CompilationGraph::writeGraph(const std::string& OutputFilename) {
 637   std::string ErrorInfo;
 638   raw_fd_ostream O(OutputFilename.c_str(), ErrorInfo);
 639
 640   if (ErrorInfo.empty()) {
 641     errs() << "Writing '"<< OutputFilename << "' file...";
 642     llvm::WriteGraph(O, this);
 643     errs() << "done.\n";
 644   }
 645   else {
 646     PrintError("Error opening file '" + OutputFilename + "' for writing!");
 647     return 1;
 648   }
 649
 650   return 0;
 651 }
 652
 653 void CompilationGraph::viewGraph() {
 654   llvm::ViewGraph(this, "compilation-graph");
 655 }