clang-tools  11.0.0
PreprocessorTracker.cpp
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1 //===--- PreprocessorTracker.cpp - Preprocessor tracking -*- C++ -*------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===--------------------------------------------------------------------===//
8 //
9 // The Basic Idea (Macro and Conditional Checking)
10 //
11 // Basically we install a PPCallbacks-derived object to track preprocessor
12 // activity, namely when a header file is entered/exited, when a macro
13 // is expanded, when "defined" is used, and when #if, #elif, #ifdef,
14 // and #ifndef are used. We save the state of macro and "defined"
15 // expressions in a map, keyed on a name/file/line/column quadruple.
16 // The map entries store the different states (values) that a macro expansion,
17 // "defined" expression, or condition expression has in the course of
18 // processing for the one location in the one header containing it,
19 // plus a list of the nested include stacks for the states. When a macro
20 // or "defined" expression evaluates to the same value, which is the
21 // desired case, only one state is stored. Similarly, for conditional
22 // directives, we save the condition expression states in a separate map.
23 //
24 // This information is collected as modularize compiles all the headers
25 // given to it to process. After all the compilations are performed,
26 // a check is performed for any entries in the maps that contain more
27 // than one different state, and for these an output message is generated.
28 //
29 // For example:
30 //
31 // (...)/SubHeader.h:11:5:
32 // #if SYMBOL == 1
33 // ^
34 // error: Macro instance 'SYMBOL' has different values in this header,
35 // depending on how it was included.
36 // 'SYMBOL' expanded to: '1' with respect to these inclusion paths:
37 // (...)/Header1.h
38 // (...)/SubHeader.h
39 // (...)/SubHeader.h:3:9:
40 // #define SYMBOL 1
41 // ^
42 // Macro defined here.
43 // 'SYMBOL' expanded to: '2' with respect to these inclusion paths:
44 // (...)/Header2.h
45 // (...)/SubHeader.h
46 // (...)/SubHeader.h:7:9:
47 // #define SYMBOL 2
48 // ^
49 // Macro defined here.
50 //
51 // The Basic Idea ('Extern "C/C++" {}' Or 'namespace {}') With Nested
52 // '#include' Checking)
53 //
54 // To check for '#include' directives nested inside 'Extern "C/C++" {}'
55 // or 'namespace {}' blocks, we keep track of the '#include' directives
56 // while running the preprocessor, and later during a walk of the AST
57 // we call a function to check for any '#include' directives inside
58 // an 'Extern "C/C++" {}' or 'namespace {}' block, given its source
59 // range.
60 //
61 // Design and Implementation Details (Macro and Conditional Checking)
62 //
63 // A PreprocessorTrackerImpl class implements the PreprocessorTracker
64 // interface. It uses a PreprocessorCallbacks class derived from PPCallbacks
65 // to track preprocessor activity, namely entering/exiting a header, macro
66 // expansions, use of "defined" expressions, and #if, #elif, #ifdef, and
67 // #ifndef conditional directives. PreprocessorTrackerImpl stores a map
68 // of MacroExpansionTracker objects keyed on a name/file/line/column
69 // value represented by a light-weight PPItemKey value object. This
70 // is the key top-level data structure tracking the values of macro
71 // expansion instances. Similarly, it stores a map of ConditionalTracker
72 // objects with the same kind of key, for tracking preprocessor conditional
73 // directives.
74 //
75 // The MacroExpansionTracker object represents one macro reference or use
76 // of a "defined" expression in a header file. It stores a handle to a
77 // string representing the unexpanded macro instance, a handle to a string
78 // representing the unpreprocessed source line containing the unexpanded
79 // macro instance, and a vector of one or more MacroExpansionInstance
80 // objects.
81 //
82 // The MacroExpansionInstance object represents one or more expansions
83 // of a macro reference, for the case where the macro expands to the same
84 // value. MacroExpansionInstance stores a handle to a string representing
85 // the expanded macro value, a PPItemKey representing the file/line/column
86 // where the macro was defined, a handle to a string representing the source
87 // line containing the macro definition, and a vector of InclusionPathHandle
88 // values that represents the hierarchies of include files for each case
89 // where the particular header containing the macro reference was referenced
90 // or included.
91 
92 // In the normal case where a macro instance always expands to the same
93 // value, the MacroExpansionTracker object will only contain one
94 // MacroExpansionInstance representing all the macro expansion instances.
95 // If a case was encountered where a macro instance expands to a value
96 // that is different from that seen before, or the macro was defined in
97 // a different place, a new MacroExpansionInstance object representing
98 // that case will be added to the vector in MacroExpansionTracker. If a
99 // macro instance expands to a value already seen before, the
100 // InclusionPathHandle representing that case's include file hierarchy
101 // will be added to the existing MacroExpansionInstance object.
102 
103 // For checking conditional directives, the ConditionalTracker class
104 // functions similarly to MacroExpansionTracker, but tracks an #if,
105 // #elif, #ifdef, or #ifndef directive in a header file. It stores
106 // a vector of one or two ConditionalExpansionInstance objects,
107 // representing the cases where the conditional expression evaluates
108 // to true or false. This latter object stores the evaluated value
109 // of the condition expression (a bool) and a vector of
110 // InclusionPathHandles.
111 //
112 // To reduce the instances of string and object copying, the
113 // PreprocessorTrackerImpl class uses a StringPool to save all stored
114 // strings, and defines a StringHandle type to abstract the references
115 // to the strings.
116 //
117 // PreprocessorTrackerImpl also maintains a list representing the unique
118 // headers, which is just a vector of StringHandle's for the header file
119 // paths. A HeaderHandle abstracts a reference to a header, and is simply
120 // the index of the stored header file path.
121 //
122 // A HeaderInclusionPath class abstracts a unique hierarchy of header file
123 // inclusions. It simply stores a vector of HeaderHandles ordered from the
124 // top-most header (the one from the header list passed to modularize) down
125 // to the header containing the macro reference. PreprocessorTrackerImpl
126 // stores a vector of these objects. An InclusionPathHandle typedef
127 // abstracts a reference to one of the HeaderInclusionPath objects, and is
128 // simply the index of the stored HeaderInclusionPath object. The
129 // MacroExpansionInstance object stores a vector of these handles so that
130 // the reporting function can display the include hierarchies for the macro
131 // expansion instances represented by that object, to help the user
132 // understand how the header was included. (A future enhancement might
133 // be to associate a line number for the #include directives, but I
134 // think not doing so is good enough for the present.)
135 //
136 // A key reason for using these opaque handles was to try to keep all the
137 // internal objects light-weight value objects, in order to reduce string
138 // and object copying overhead, and to abstract this implementation detail.
139 //
140 // The key data structures are built up while modularize runs the headers
141 // through the compilation. A PreprocessorTracker instance is created and
142 // passed down to the AST action and consumer objects in modularize. For
143 // each new compilation instance, the consumer calls the
144 // PreprocessorTracker's handleNewPreprocessorEntry function, which sets
145 // up a PreprocessorCallbacks object for the preprocessor. At the end of
146 // the compilation instance, the PreprocessorTracker's
147 // handleNewPreprocessorExit function handles cleaning up with respect
148 // to the preprocessing instance.
149 //
150 // The PreprocessorCallbacks object uses an overridden FileChanged callback
151 // to determine when a header is entered and exited (including exiting the
152 // header during #include directives). It calls PreprocessorTracker's
153 // handleHeaderEntry and handleHeaderExit functions upon entering and
154 // exiting a header. These functions manage a stack of header handles
155 // representing by a vector, pushing and popping header handles as headers
156 // are entered and exited. When a HeaderInclusionPath object is created,
157 // it simply copies this stack.
158 //
159 // The PreprocessorCallbacks object uses an overridden MacroExpands callback
160 // to track when a macro expansion is performed. It calls a couple of helper
161 // functions to get the unexpanded and expanded macro values as strings, but
162 // then calls PreprocessorTrackerImpl's addMacroExpansionInstance function to
163 // do the rest of the work. The getMacroExpandedString function uses the
164 // preprocessor's getSpelling to convert tokens to strings using the
165 // information passed to the MacroExpands callback, and simply concatenates
166 // them. It makes recursive calls to itself to handle nested macro
167 // definitions, and also handles function-style macros.
168 //
169 // PreprocessorTrackerImpl's addMacroExpansionInstance function looks for
170 // an existing MacroExpansionTracker entry in its map of MacroExampleTracker
171 // objects. If none exists, it adds one with one MacroExpansionInstance and
172 // returns. If a MacroExpansionTracker object already exists, it looks for
173 // an existing MacroExpansionInstance object stored in the
174 // MacroExpansionTracker object, one that matches the macro expanded value
175 // and the macro definition location. If a matching MacroExpansionInstance
176 // object is found, it just adds the current HeaderInclusionPath object to
177 // it. If not found, it creates and stores a new MacroExpansionInstance
178 // object. The addMacroExpansionInstance function calls a couple of helper
179 // functions to get the pre-formatted location and source line strings for
180 // the macro reference and the macro definition stored as string handles.
181 // These helper functions use the current source manager from the
182 // preprocessor. This is done in advance at this point in time because the
183 // source manager doesn't exist at the time of the reporting.
184 //
185 // For conditional check, the PreprocessorCallbacks class overrides the
186 // PPCallbacks handlers for #if, #elif, #ifdef, and #ifndef. These handlers
187 // call the addConditionalExpansionInstance method of
188 // PreprocessorTrackerImpl. The process is similar to that of macros, but
189 // with some different data and error messages. A lookup is performed for
190 // the conditional, and if a ConditionalTracker object doesn't yet exist for
191 // the conditional, a new one is added, including adding a
192 // ConditionalExpansionInstance object to it to represent the condition
193 // expression state. If a ConditionalTracker for the conditional does
194 // exist, a lookup is made for a ConditionalExpansionInstance object
195 // matching the condition expression state. If one exists, a
196 // HeaderInclusionPath is added to it. Otherwise a new
197 // ConditionalExpansionInstance entry is made. If a ConditionalTracker
198 // has two ConditionalExpansionInstance objects, it means there was a
199 // conflict, meaning the conditional expression evaluated differently in
200 // one or more cases.
201 //
202 // After modularize has performed all the compilations, it enters a phase
203 // of error reporting. This new feature adds to this reporting phase calls
204 // to the PreprocessorTracker's reportInconsistentMacros and
205 // reportInconsistentConditionals functions. These functions walk the maps
206 // of MacroExpansionTracker's and ConditionalTracker's respectively. If
207 // any of these objects have more than one MacroExpansionInstance or
208 // ConditionalExpansionInstance objects, it formats and outputs an error
209 // message like the example shown previously, using the stored data.
210 //
211 // A potential issue is that there is some overlap between the #if/#elif
212 // conditional and macro reporting. I could disable the #if and #elif,
213 // leaving just the #ifdef and #ifndef, since these don't overlap. Or,
214 // to make clearer the separate reporting phases, I could add an output
215 // message marking the phases.
216 //
217 // Design and Implementation Details ('Extern "C/C++" {}' Or
218 // 'namespace {}') With Nested '#include' Checking)
219 //
220 // We override the InclusionDirective in PPCallbacks to record information
221 // about each '#include' directive encountered during preprocessing.
222 // We co-opt the PPItemKey class to store the information about each
223 // '#include' directive, including the source file name containing the
224 // directive, the name of the file being included, and the source line
225 // and column of the directive. We store these object in a vector,
226 // after first check to see if an entry already exists.
227 //
228 // Later, while the AST is being walked for other checks, we provide
229 // visit handlers for 'extern "C/C++" {}' and 'namespace (name) {}'
230 // blocks, checking to see if any '#include' directives occurred
231 // within the blocks, reporting errors if any found.
232 //
233 // Future Directions
234 //
235 // We probably should add options to disable any of the checks, in case
236 // there is some problem with them, or the messages get too verbose.
237 //
238 // With the map of all the macro and conditional expansion instances,
239 // it might be possible to add to the existing modularize error messages
240 // (the second part referring to definitions being different), attempting
241 // to tie them to the last macro conflict encountered with respect to the
242 // order of the code encountered.
243 //
244 //===--------------------------------------------------------------------===//
245 
246 #include "PreprocessorTracker.h"
247 #include "ModularizeUtilities.h"
248 #include "clang/Lex/LexDiagnostic.h"
249 #include "clang/Lex/MacroArgs.h"
250 #include "clang/Lex/PPCallbacks.h"
251 #include "llvm/ADT/SmallSet.h"
252 #include "llvm/ADT/StringSet.h"
253 #include "llvm/Support/raw_ostream.h"
254 
255 namespace Modularize {
256 
257 // Some handle types
258 typedef llvm::StringRef StringHandle;
259 
260 typedef int HeaderHandle;
262 
265 
266 // Some utility functions.
267 
268 // Get a "file:line:column" source location string.
269 static std::string getSourceLocationString(clang::Preprocessor &PP,
270  clang::SourceLocation Loc) {
271  if (Loc.isInvalid())
272  return std::string("(none)");
273  else
274  return Loc.printToString(PP.getSourceManager());
275 }
276 
277 // Get just the file name from a source location.
278 static std::string getSourceLocationFile(clang::Preprocessor &PP,
279  clang::SourceLocation Loc) {
280  std::string Source(getSourceLocationString(PP, Loc));
281  size_t Offset = Source.find(':', 2);
282  if (Offset == std::string::npos)
283  return Source;
284  return Source.substr(0, Offset);
285 }
286 
287 // Get just the line and column from a source location.
288 static void getSourceLocationLineAndColumn(clang::Preprocessor &PP,
289  clang::SourceLocation Loc, int &Line,
290  int &Column) {
291  clang::PresumedLoc PLoc = PP.getSourceManager().getPresumedLoc(Loc);
292  if (PLoc.isInvalid()) {
293  Line = 0;
294  Column = 0;
295  return;
296  }
297  Line = PLoc.getLine();
298  Column = PLoc.getColumn();
299 }
300 
301 // Retrieve source snippet from file image.
302 static std::string getSourceString(clang::Preprocessor &PP,
303  clang::SourceRange Range) {
304  clang::SourceLocation BeginLoc = Range.getBegin();
305  clang::SourceLocation EndLoc = Range.getEnd();
306  const char *BeginPtr = PP.getSourceManager().getCharacterData(BeginLoc);
307  const char *EndPtr = PP.getSourceManager().getCharacterData(EndLoc);
308  size_t Length = EndPtr - BeginPtr;
309  return llvm::StringRef(BeginPtr, Length).trim().str();
310 }
311 
312 // Retrieve source line from file image given a location.
313 static std::string getSourceLine(clang::Preprocessor &PP,
314  clang::SourceLocation Loc) {
315  const llvm::MemoryBuffer *MemBuffer =
316  PP.getSourceManager().getBuffer(PP.getSourceManager().getFileID(Loc));
317  const char *Buffer = MemBuffer->getBufferStart();
318  const char *BufferEnd = MemBuffer->getBufferEnd();
319  const char *BeginPtr = PP.getSourceManager().getCharacterData(Loc);
320  const char *EndPtr = BeginPtr;
321  while (BeginPtr > Buffer) {
322  if (*BeginPtr == '\n') {
323  BeginPtr++;
324  break;
325  }
326  BeginPtr--;
327  }
328  while (EndPtr < BufferEnd) {
329  if (*EndPtr == '\n') {
330  break;
331  }
332  EndPtr++;
333  }
334  size_t Length = EndPtr - BeginPtr;
335  return llvm::StringRef(BeginPtr, Length).str();
336 }
337 
338 // Retrieve source line from file image given a file ID and line number.
339 static std::string getSourceLine(clang::Preprocessor &PP, clang::FileID FileID,
340  int Line) {
341  const llvm::MemoryBuffer *MemBuffer = PP.getSourceManager().getBuffer(FileID);
342  const char *Buffer = MemBuffer->getBufferStart();
343  const char *BufferEnd = MemBuffer->getBufferEnd();
344  const char *BeginPtr = Buffer;
345  const char *EndPtr = BufferEnd;
346  int LineCounter = 1;
347  if (Line == 1)
348  BeginPtr = Buffer;
349  else {
350  while (Buffer < BufferEnd) {
351  if (*Buffer == '\n') {
352  if (++LineCounter == Line) {
353  BeginPtr = Buffer++ + 1;
354  break;
355  }
356  }
357  Buffer++;
358  }
359  }
360  while (Buffer < BufferEnd) {
361  if (*Buffer == '\n') {
362  EndPtr = Buffer;
363  break;
364  }
365  Buffer++;
366  }
367  size_t Length = EndPtr - BeginPtr;
368  return llvm::StringRef(BeginPtr, Length).str();
369 }
370 
371 // Get the string for the Unexpanded macro instance.
372 // The sourceRange is expected to end at the last token
373 // for the macro instance, which in the case of a function-style
374 // macro will be a ')', but for an object-style macro, it
375 // will be the macro name itself.
376 static std::string getMacroUnexpandedString(clang::SourceRange Range,
377  clang::Preprocessor &PP,
378  llvm::StringRef MacroName,
379  const clang::MacroInfo *MI) {
380  clang::SourceLocation BeginLoc(Range.getBegin());
381  const char *BeginPtr = PP.getSourceManager().getCharacterData(BeginLoc);
382  size_t Length;
383  std::string Unexpanded;
384  if (MI->isFunctionLike()) {
385  clang::SourceLocation EndLoc(Range.getEnd());
386  const char *EndPtr = PP.getSourceManager().getCharacterData(EndLoc) + 1;
387  Length = (EndPtr - BeginPtr) + 1; // +1 is ')' width.
388  } else
389  Length = MacroName.size();
390  return llvm::StringRef(BeginPtr, Length).trim().str();
391 }
392 
393 // Get the expansion for a macro instance, given the information
394 // provided by PPCallbacks.
395 // FIXME: This doesn't support function-style macro instances
396 // passed as arguments to another function-style macro. However,
397 // since it still expands the inner arguments, it still
398 // allows modularize to effectively work with respect to macro
399 // consistency checking, although it displays the incorrect
400 // expansion in error messages.
401 static std::string getMacroExpandedString(clang::Preprocessor &PP,
402  llvm::StringRef MacroName,
403  const clang::MacroInfo *MI,
404  const clang::MacroArgs *Args) {
405  std::string Expanded;
406  // Walk over the macro Tokens.
407  for (const auto &T : MI->tokens()) {
408  clang::IdentifierInfo *II = T.getIdentifierInfo();
409  int ArgNo = (II && Args ? MI->getParameterNum(II) : -1);
410  if (ArgNo == -1) {
411  // This isn't an argument, just add it.
412  if (II == nullptr)
413  Expanded += PP.getSpelling(T); // Not an identifier.
414  else {
415  // Token is for an identifier.
416  std::string Name = II->getName().str();
417  // Check for nexted macro references.
418  clang::MacroInfo *MacroInfo = PP.getMacroInfo(II);
419  if (MacroInfo && (Name != MacroName))
420  Expanded += getMacroExpandedString(PP, Name, MacroInfo, nullptr);
421  else
422  Expanded += Name;
423  }
424  continue;
425  }
426  // We get here if it's a function-style macro with arguments.
427  const clang::Token *ResultArgToks;
428  const clang::Token *ArgTok = Args->getUnexpArgument(ArgNo);
429  if (Args->ArgNeedsPreexpansion(ArgTok, PP))
430  ResultArgToks = &(const_cast<clang::MacroArgs *>(Args))
431  ->getPreExpArgument(ArgNo, PP)[0];
432  else
433  ResultArgToks = ArgTok; // Use non-preexpanded Tokens.
434  // If the arg token didn't expand into anything, ignore it.
435  if (ResultArgToks->is(clang::tok::eof))
436  continue;
437  unsigned NumToks = clang::MacroArgs::getArgLength(ResultArgToks);
438  // Append the resulting argument expansions.
439  for (unsigned ArgumentIndex = 0; ArgumentIndex < NumToks; ++ArgumentIndex) {
440  const clang::Token &AT = ResultArgToks[ArgumentIndex];
441  clang::IdentifierInfo *II = AT.getIdentifierInfo();
442  if (II == nullptr)
443  Expanded += PP.getSpelling(AT); // Not an identifier.
444  else {
445  // It's an identifier. Check for further expansion.
446  std::string Name = II->getName().str();
447  clang::MacroInfo *MacroInfo = PP.getMacroInfo(II);
448  if (MacroInfo)
449  Expanded += getMacroExpandedString(PP, Name, MacroInfo, nullptr);
450  else
451  Expanded += Name;
452  }
453  }
454  }
455  return Expanded;
456 }
457 
458 namespace {
459 
460 // ConditionValueKind strings.
461 const char *
463  "(not evaluated)", "false", "true"
464 };
465 
466 // Preprocessor item key.
467 //
468 // This class represents a location in a source file, for use
469 // as a key representing a unique name/file/line/column quadruplet,
470 // which in this case is used to identify a macro expansion instance,
471 // but could be used for other things as well.
472 // The file is a header file handle, the line is a line number,
473 // and the column is a column number.
474 class PPItemKey {
475 public:
476  PPItemKey(clang::Preprocessor &PP, StringHandle Name, HeaderHandle File,
477  clang::SourceLocation Loc)
478  : Name(Name), File(File) {
480  }
481  PPItemKey(StringHandle Name, HeaderHandle File, int Line, int Column)
482  : Name(Name), File(File), Line(Line), Column(Column) {}
483  PPItemKey(const PPItemKey &Other)
484  : Name(Other.Name), File(Other.File), Line(Other.Line),
485  Column(Other.Column) {}
486  PPItemKey() : File(HeaderHandleInvalid), Line(0), Column(0) {}
487  bool operator==(const PPItemKey &Other) const {
488  if (Name != Other.Name)
489  return false;
490  if (File != Other.File)
491  return false;
492  if (Line != Other.Line)
493  return false;
494  return Column == Other.Column;
495  }
496  bool operator<(const PPItemKey &Other) const {
497  if (Name < Other.Name)
498  return true;
499  else if (Name > Other.Name)
500  return false;
501  if (File < Other.File)
502  return true;
503  else if (File > Other.File)
504  return false;
505  if (Line < Other.Line)
506  return true;
507  else if (Line > Other.Line)
508  return false;
509  return Column < Other.Column;
510  }
513  int Line;
514  int Column;
515 };
516 
517 // Header inclusion path.
518 class HeaderInclusionPath {
519 public:
520  HeaderInclusionPath(std::vector<HeaderHandle> HeaderInclusionPath)
521  : Path(HeaderInclusionPath) {}
522  HeaderInclusionPath(const HeaderInclusionPath &Other) : Path(Other.Path) {}
523  HeaderInclusionPath() {}
524  std::vector<HeaderHandle> Path;
525 };
526 
527 // Macro expansion instance.
528 //
529 // This class represents an instance of a macro expansion with a
530 // unique value. It also stores the unique header inclusion paths
531 // for use in telling the user the nested include path to the header.
532 class MacroExpansionInstance {
533 public:
534  MacroExpansionInstance(StringHandle MacroExpanded,
535  PPItemKey &DefinitionLocation,
540  InclusionPathHandles.push_back(H);
541  }
542  MacroExpansionInstance() {}
543 
544  // Check for the presence of a header inclusion path handle entry.
545  // Return false if not found.
546  bool haveInclusionPathHandle(InclusionPathHandle H) {
547  for (auto I = InclusionPathHandles.begin(), E = InclusionPathHandles.end();
548  I != E; ++I) {
549  if (*I == H)
550  return true;
551  }
553  }
554  // Add a new header inclusion path entry, if not already present.
555  void addInclusionPathHandle(InclusionPathHandle H) {
556  if (!haveInclusionPathHandle(H))
557  InclusionPathHandles.push_back(H);
558  }
559 
560  // A string representing the macro instance after preprocessing.
562  // A file/line/column triplet representing the macro definition location.
564  // A place to save the macro definition line string.
566  // The header inclusion path handles for all the instances.
567  std::vector<InclusionPathHandle> InclusionPathHandles;
568 };
569 
570 // Macro expansion instance tracker.
571 //
572 // This class represents one macro expansion, keyed by a PPItemKey.
573 // It stores a string representing the macro reference in the source,
574 // and a list of ConditionalExpansionInstances objects representing
575 // the unique values the condition expands to in instances of the header.
576 class MacroExpansionTracker {
577 public:
578  MacroExpansionTracker(StringHandle MacroUnexpanded,
581  PPItemKey &DefinitionLocation,
586  addMacroExpansionInstance(MacroExpanded, DefinitionLocation,
588  }
589  MacroExpansionTracker() {}
590 
591  // Find a matching macro expansion instance.
592  MacroExpansionInstance *
593  findMacroExpansionInstance(StringHandle MacroExpanded,
594  PPItemKey &DefinitionLocation) {
595  for (auto I = MacroExpansionInstances.begin(),
596  E = MacroExpansionInstances.end();
597  I != E; ++I) {
598  if ((I->MacroExpanded == MacroExpanded) &&
599  (I->DefinitionLocation == DefinitionLocation)) {
600  return &*I; // Found.
601  }
602  }
603  return nullptr; // Not found.
604  }
605 
606  // Add a macro expansion instance.
607  void addMacroExpansionInstance(StringHandle MacroExpanded,
608  PPItemKey &DefinitionLocation,
611  MacroExpansionInstances.push_back(
612  MacroExpansionInstance(MacroExpanded, DefinitionLocation,
614  }
615 
616  // Return true if there is a mismatch.
617  bool hasMismatch() { return MacroExpansionInstances.size() > 1; }
618 
619  // A string representing the macro instance without expansion.
621  // A place to save the macro instance source line string.
623  // The macro expansion instances.
624  // If all instances of the macro expansion expand to the same value,
625  // This vector will only have one instance.
626  std::vector<MacroExpansionInstance> MacroExpansionInstances;
627 };
628 
629 // Conditional expansion instance.
630 //
631 // This class represents an instance of a condition exoression result
632 // with a unique value. It also stores the unique header inclusion paths
633 // for use in telling the user the nested include path to the header.
634 class ConditionalExpansionInstance {
635 public:
636  ConditionalExpansionInstance(clang::PPCallbacks::ConditionValueKind ConditionValue, InclusionPathHandle H)
638  InclusionPathHandles.push_back(H);
639  }
640  ConditionalExpansionInstance() {}
641 
642  // Check for the presence of a header inclusion path handle entry.
643  // Return false if not found.
644  bool haveInclusionPathHandle(InclusionPathHandle H) {
645  for (auto I = InclusionPathHandles.begin(), E = InclusionPathHandles.end();
646  I != E; ++I) {
647  if (*I == H)
648  return true;
649  }
651  }
652  // Add a new header inclusion path entry, if not already present.
653  void addInclusionPathHandle(InclusionPathHandle H) {
654  if (!haveInclusionPathHandle(H))
655  InclusionPathHandles.push_back(H);
656  }
657 
658  // A flag representing the evaluated condition value.
659  clang::PPCallbacks::ConditionValueKind ConditionValue;
660  // The header inclusion path handles for all the instances.
661  std::vector<InclusionPathHandle> InclusionPathHandles;
662 };
663 
664 // Conditional directive instance tracker.
665 //
666 // This class represents one conditional directive, keyed by a PPItemKey.
667 // It stores a string representing the macro reference in the source,
668 // and a list of ConditionExpansionInstance objects representing
669 // the unique value the condition expression expands to in instances of
670 // the header.
671 class ConditionalTracker {
672 public:
673  ConditionalTracker(clang::tok::PPKeywordKind DirectiveKind,
674  clang::PPCallbacks::ConditionValueKind ConditionValue,
678  addConditionalExpansionInstance(ConditionValue, InclusionPathHandle);
679  }
680  ConditionalTracker() {}
681 
682  // Find a matching condition expansion instance.
683  ConditionalExpansionInstance *
684  findConditionalExpansionInstance(clang::PPCallbacks::ConditionValueKind ConditionValue) {
685  for (auto I = ConditionalExpansionInstances.begin(),
687  I != E; ++I) {
688  if (I->ConditionValue == ConditionValue) {
689  return &*I; // Found.
690  }
691  }
692  return nullptr; // Not found.
693  }
694 
695  // Add a conditional expansion instance.
696  void
697  addConditionalExpansionInstance(clang::PPCallbacks::ConditionValueKind ConditionValue,
700  ConditionalExpansionInstance(ConditionValue, InclusionPathHandle));
701  }
702 
703  // Return true if there is a mismatch.
704  bool hasMismatch() { return ConditionalExpansionInstances.size() > 1; }
705 
706  // The kind of directive.
707  clang::tok::PPKeywordKind DirectiveKind;
708  // A string representing the macro instance without expansion.
710  // The condition expansion instances.
711  // If all instances of the conditional expression expand to the same value,
712  // This vector will only have one instance.
713  std::vector<ConditionalExpansionInstance> ConditionalExpansionInstances;
714 };
715 
716 class PreprocessorTrackerImpl;
717 
718 // Preprocessor callbacks for modularize.
719 //
720 // This class derives from the Clang PPCallbacks class to track preprocessor
721 // actions, such as changing files and handling preprocessor directives and
722 // macro expansions. It has to figure out when a new header file is entered
723 // and left, as the provided handler is not particularly clear about it.
724 class PreprocessorCallbacks : public clang::PPCallbacks {
725 public:
726  PreprocessorCallbacks(PreprocessorTrackerImpl &ppTracker,
727  clang::Preprocessor &PP, llvm::StringRef rootHeaderFile)
728  : PPTracker(ppTracker), PP(PP), RootHeaderFile(rootHeaderFile) {}
729  ~PreprocessorCallbacks() override {}
730 
731  // Overridden handlers.
732  void InclusionDirective(clang::SourceLocation HashLoc,
733  const clang::Token &IncludeTok,
734  llvm::StringRef FileName, bool IsAngled,
735  clang::CharSourceRange FilenameRange,
736  const clang::FileEntry *File,
737  llvm::StringRef SearchPath,
738  llvm::StringRef RelativePath,
739  const clang::Module *Imported,
740  clang::SrcMgr::CharacteristicKind FileType) override;
741  void FileChanged(clang::SourceLocation Loc,
742  clang::PPCallbacks::FileChangeReason Reason,
743  clang::SrcMgr::CharacteristicKind FileType,
744  clang::FileID PrevFID = clang::FileID()) override;
745  void MacroExpands(const clang::Token &MacroNameTok,
746  const clang::MacroDefinition &MD, clang::SourceRange Range,
747  const clang::MacroArgs *Args) override;
748  void Defined(const clang::Token &MacroNameTok,
749  const clang::MacroDefinition &MD,
750  clang::SourceRange Range) override;
751  void If(clang::SourceLocation Loc, clang::SourceRange ConditionRange,
752  clang::PPCallbacks::ConditionValueKind ConditionResult) override;
753  void Elif(clang::SourceLocation Loc, clang::SourceRange ConditionRange,
754  clang::PPCallbacks::ConditionValueKind ConditionResult,
755  clang::SourceLocation IfLoc) override;
756  void Ifdef(clang::SourceLocation Loc, const clang::Token &MacroNameTok,
757  const clang::MacroDefinition &MD) override;
758  void Ifndef(clang::SourceLocation Loc, const clang::Token &MacroNameTok,
759  const clang::MacroDefinition &MD) override;
760 
761 private:
762  PreprocessorTrackerImpl &PPTracker;
763  clang::Preprocessor &PP;
764  std::string RootHeaderFile;
765 };
766 
767 // Preprocessor macro expansion item map types.
768 typedef std::map<PPItemKey, MacroExpansionTracker> MacroExpansionMap;
769 typedef std::map<PPItemKey, MacroExpansionTracker>::iterator
770 MacroExpansionMapIter;
771 
772 // Preprocessor conditional expansion item map types.
773 typedef std::map<PPItemKey, ConditionalTracker> ConditionalExpansionMap;
774 typedef std::map<PPItemKey, ConditionalTracker>::iterator
775 ConditionalExpansionMapIter;
776 
777 // Preprocessor tracker for modularize.
778 //
779 // This class stores information about all the headers processed in the
780 // course of running modularize.
781 class PreprocessorTrackerImpl : public PreprocessorTracker {
782 public:
783  PreprocessorTrackerImpl(llvm::SmallVector<std::string, 32> &Headers,
784  bool DoBlockCheckHeaderListOnly)
785  : BlockCheckHeaderListOnly(DoBlockCheckHeaderListOnly),
786  CurrentInclusionPathHandle(InclusionPathHandleInvalid),
787  InNestedHeader(false) {
788  // Use canonical header path representation.
789  for (llvm::ArrayRef<std::string>::iterator I = Headers.begin(),
790  E = Headers.end();
791  I != E; ++I) {
792  HeaderList.push_back(getCanonicalPath(*I));
793  }
794  }
795 
796  ~PreprocessorTrackerImpl() override {}
797 
798  // Handle entering a preprocessing session.
799  void handlePreprocessorEntry(clang::Preprocessor &PP,
800  llvm::StringRef rootHeaderFile) override {
801  HeadersInThisCompile.clear();
802  assert((HeaderStack.size() == 0) && "Header stack should be empty.");
803  pushHeaderHandle(addHeader(rootHeaderFile));
804  PP.addPPCallbacks(std::make_unique<PreprocessorCallbacks>(*this, PP,
805  rootHeaderFile));
806  }
807  // Handle exiting a preprocessing session.
808  void handlePreprocessorExit() override { HeaderStack.clear(); }
809 
810  // Handle include directive.
811  // This function is called every time an include directive is seen by the
812  // preprocessor, for the purpose of later checking for 'extern "" {}' or
813  // "namespace {}" blocks containing #include directives.
814  void handleIncludeDirective(llvm::StringRef DirectivePath, int DirectiveLine,
815  int DirectiveColumn,
816  llvm::StringRef TargetPath) override {
817  // If it's not a header in the header list, ignore it with respect to
818  // the check.
819  if (BlockCheckHeaderListOnly && !isHeaderListHeader(TargetPath))
820  return;
821  HeaderHandle CurrentHeaderHandle = findHeaderHandle(DirectivePath);
822  StringHandle IncludeHeaderHandle = addString(TargetPath);
823  for (std::vector<PPItemKey>::const_iterator I = IncludeDirectives.begin(),
824  E = IncludeDirectives.end();
825  I != E; ++I) {
826  // If we already have an entry for this directive, return now.
827  if ((I->File == CurrentHeaderHandle) && (I->Line == DirectiveLine))
828  return;
829  }
830  PPItemKey IncludeDirectiveItem(IncludeHeaderHandle, CurrentHeaderHandle,
831  DirectiveLine, DirectiveColumn);
832  IncludeDirectives.push_back(IncludeDirectiveItem);
833  }
834 
835  // Check for include directives within the given source line range.
836  // Report errors if any found. Returns true if no include directives
837  // found in block.
838  bool checkForIncludesInBlock(clang::Preprocessor &PP,
839  clang::SourceRange BlockSourceRange,
840  const char *BlockIdentifierMessage,
841  llvm::raw_ostream &OS) override {
842  clang::SourceLocation BlockStartLoc = BlockSourceRange.getBegin();
843  clang::SourceLocation BlockEndLoc = BlockSourceRange.getEnd();
844  // Use block location to get FileID of both the include directive
845  // and block statement.
846  clang::FileID FileID = PP.getSourceManager().getFileID(BlockStartLoc);
847  std::string SourcePath = getSourceLocationFile(PP, BlockStartLoc);
848  SourcePath = ModularizeUtilities::getCanonicalPath(SourcePath);
849  HeaderHandle SourceHandle = findHeaderHandle(SourcePath);
850  if (SourceHandle == -1)
851  return true;
852  int BlockStartLine, BlockStartColumn, BlockEndLine, BlockEndColumn;
853  bool returnValue = true;
854  getSourceLocationLineAndColumn(PP, BlockStartLoc, BlockStartLine,
855  BlockStartColumn);
856  getSourceLocationLineAndColumn(PP, BlockEndLoc, BlockEndLine,
857  BlockEndColumn);
858  for (std::vector<PPItemKey>::const_iterator I = IncludeDirectives.begin(),
859  E = IncludeDirectives.end();
860  I != E; ++I) {
861  // If we find an entry within the block, report an error.
862  if ((I->File == SourceHandle) && (I->Line >= BlockStartLine) &&
863  (I->Line < BlockEndLine)) {
864  returnValue = false;
865  OS << SourcePath << ":" << I->Line << ":" << I->Column << ":\n";
866  OS << getSourceLine(PP, FileID, I->Line) << "\n";
867  if (I->Column > 0)
868  OS << std::string(I->Column - 1, ' ') << "^\n";
869  OS << "error: Include directive within " << BlockIdentifierMessage
870  << ".\n";
871  OS << SourcePath << ":" << BlockStartLine << ":" << BlockStartColumn
872  << ":\n";
873  OS << getSourceLine(PP, BlockStartLoc) << "\n";
874  if (BlockStartColumn > 0)
875  OS << std::string(BlockStartColumn - 1, ' ') << "^\n";
876  OS << "The \"" << BlockIdentifierMessage << "\" block is here.\n";
877  }
878  }
879  return returnValue;
880  }
881 
882  // Handle entering a header source file.
883  void handleHeaderEntry(clang::Preprocessor &PP, llvm::StringRef HeaderPath) {
884  // Ignore <built-in> and <command-line> to reduce message clutter.
885  if (HeaderPath.startswith("<"))
886  return;
887  HeaderHandle H = addHeader(HeaderPath);
888  if (H != getCurrentHeaderHandle())
889  pushHeaderHandle(H);
890  // Check for nested header.
891  if (!InNestedHeader)
892  InNestedHeader = !HeadersInThisCompile.insert(H).second;
893  }
894 
895  // Handle exiting a header source file.
896  void handleHeaderExit(llvm::StringRef HeaderPath) {
897  // Ignore <built-in> and <command-line> to reduce message clutter.
898  if (HeaderPath.startswith("<"))
899  return;
900  HeaderHandle H = findHeaderHandle(HeaderPath);
901  HeaderHandle TH;
902  if (isHeaderHandleInStack(H)) {
903  do {
904  TH = getCurrentHeaderHandle();
905  popHeaderHandle();
906  } while ((TH != H) && (HeaderStack.size() != 0));
907  }
908  InNestedHeader = false;
909  }
910 
911  // Lookup/add string.
912  StringHandle addString(llvm::StringRef Str) {
913  return Strings.insert(Str).first->first();
914  }
915 
916  // Convert to a canonical path.
917  std::string getCanonicalPath(llvm::StringRef path) const {
918  std::string CanonicalPath(path);
919  std::replace(CanonicalPath.begin(), CanonicalPath.end(), '\\', '/');
920  return CanonicalPath;
921  }
922 
923  // Return true if the given header is in the header list.
924  bool isHeaderListHeader(llvm::StringRef HeaderPath) const {
925  std::string CanonicalPath = getCanonicalPath(HeaderPath);
926  for (llvm::ArrayRef<std::string>::iterator I = HeaderList.begin(),
927  E = HeaderList.end();
928  I != E; ++I) {
929  if (*I == CanonicalPath)
930  return true;
931  }
932  return false;
933  }
934 
935  // Get the handle of a header file entry.
936  // Return HeaderHandleInvalid if not found.
937  HeaderHandle findHeaderHandle(llvm::StringRef HeaderPath) const {
938  std::string CanonicalPath = getCanonicalPath(HeaderPath);
939  HeaderHandle H = 0;
940  for (auto I = HeaderPaths.begin(), E = HeaderPaths.end(); I != E;
941  ++I, ++H) {
942  if (*I == CanonicalPath)
943  return H;
944  }
945  return HeaderHandleInvalid;
946  }
947 
948  // Add a new header file entry, or return existing handle.
949  // Return the header handle.
950  HeaderHandle addHeader(llvm::StringRef HeaderPath) {
951  std::string CanonicalPath = getCanonicalPath(HeaderPath);
952  HeaderHandle H = findHeaderHandle(CanonicalPath);
953  if (H == HeaderHandleInvalid) {
954  H = HeaderPaths.size();
955  HeaderPaths.push_back(addString(CanonicalPath));
956  }
957  return H;
958  }
959 
960  // Return a header file path string given its handle.
961  StringHandle getHeaderFilePath(HeaderHandle H) const {
962  if ((H >= 0) && (H < (HeaderHandle)HeaderPaths.size()))
963  return HeaderPaths[H];
964  return StringHandle();
965  }
966 
967  // Returns a handle to the inclusion path.
968  InclusionPathHandle pushHeaderHandle(HeaderHandle H) {
969  HeaderStack.push_back(H);
970  return CurrentInclusionPathHandle = addInclusionPathHandle(HeaderStack);
971  }
972  // Pops the last header handle from the stack;
973  void popHeaderHandle() {
974  // assert((HeaderStack.size() != 0) && "Header stack already empty.");
975  if (HeaderStack.size() != 0) {
976  HeaderStack.pop_back();
977  CurrentInclusionPathHandle = addInclusionPathHandle(HeaderStack);
978  }
979  }
980  // Get the top handle on the header stack.
981  HeaderHandle getCurrentHeaderHandle() const {
982  if (HeaderStack.size() != 0)
983  return HeaderStack.back();
984  return HeaderHandleInvalid;
985  }
986 
987  // Check for presence of header handle in the header stack.
988  bool isHeaderHandleInStack(HeaderHandle H) const {
989  for (auto I = HeaderStack.begin(), E = HeaderStack.end(); I != E; ++I) {
990  if (*I == H)
991  return true;
992  }
993  return false;
994  }
995 
996  // Get the handle of a header inclusion path entry.
997  // Return InclusionPathHandleInvalid if not found.
999  findInclusionPathHandle(const std::vector<HeaderHandle> &Path) const {
1000  InclusionPathHandle H = 0;
1001  for (auto I = InclusionPaths.begin(), E = InclusionPaths.end(); I != E;
1002  ++I, ++H) {
1003  if (I->Path == Path)
1004  return H;
1005  }
1006  return HeaderHandleInvalid;
1007  }
1008  // Add a new header inclusion path entry, or return existing handle.
1009  // Return the header inclusion path entry handle.
1011  addInclusionPathHandle(const std::vector<HeaderHandle> &Path) {
1012  InclusionPathHandle H = findInclusionPathHandle(Path);
1013  if (H == HeaderHandleInvalid) {
1014  H = InclusionPaths.size();
1015  InclusionPaths.push_back(HeaderInclusionPath(Path));
1016  }
1017  return H;
1018  }
1019  // Return the current inclusion path handle.
1020  InclusionPathHandle getCurrentInclusionPathHandle() const {
1021  return CurrentInclusionPathHandle;
1022  }
1023 
1024  // Return an inclusion path given its handle.
1025  const std::vector<HeaderHandle> &
1026  getInclusionPath(InclusionPathHandle H) const {
1027  if ((H >= 0) && (H <= (InclusionPathHandle)InclusionPaths.size()))
1028  return InclusionPaths[H].Path;
1029  static std::vector<HeaderHandle> Empty;
1030  return Empty;
1031  }
1032 
1033  // Add a macro expansion instance.
1034  void addMacroExpansionInstance(clang::Preprocessor &PP, HeaderHandle H,
1035  clang::SourceLocation InstanceLoc,
1036  clang::SourceLocation DefinitionLoc,
1037  clang::IdentifierInfo *II,
1038  llvm::StringRef MacroUnexpanded,
1039  llvm::StringRef MacroExpanded,
1041  if (InNestedHeader)
1042  return;
1043  StringHandle MacroName = addString(II->getName());
1044  PPItemKey InstanceKey(PP, MacroName, H, InstanceLoc);
1045  PPItemKey DefinitionKey(PP, MacroName, H, DefinitionLoc);
1046  auto I = MacroExpansions.find(InstanceKey);
1047  // If existing instance of expansion not found, add one.
1048  if (I == MacroExpansions.end()) {
1049  std::string InstanceSourceLine =
1050  getSourceLocationString(PP, InstanceLoc) + ":\n" +
1051  getSourceLine(PP, InstanceLoc) + "\n";
1052  std::string DefinitionSourceLine =
1053  getSourceLocationString(PP, DefinitionLoc) + ":\n" +
1054  getSourceLine(PP, DefinitionLoc) + "\n";
1055  MacroExpansions[InstanceKey] = MacroExpansionTracker(
1056  addString(MacroUnexpanded), addString(MacroExpanded),
1057  addString(InstanceSourceLine), DefinitionKey,
1059  } else {
1060  // We've seen the macro before. Get its tracker.
1061  MacroExpansionTracker &CondTracker = I->second;
1062  // Look up an existing instance value for the macro.
1063  MacroExpansionInstance *MacroInfo =
1064  CondTracker.findMacroExpansionInstance(addString(MacroExpanded),
1065  DefinitionKey);
1066  // If found, just add the inclusion path to the instance.
1067  if (MacroInfo)
1068  MacroInfo->addInclusionPathHandle(InclusionPathHandle);
1069  else {
1070  // Otherwise add a new instance with the unique value.
1071  std::string DefinitionSourceLine =
1072  getSourceLocationString(PP, DefinitionLoc) + ":\n" +
1073  getSourceLine(PP, DefinitionLoc) + "\n";
1074  CondTracker.addMacroExpansionInstance(
1075  addString(MacroExpanded), DefinitionKey,
1077  }
1078  }
1079  }
1080 
1081  // Add a conditional expansion instance.
1082  void
1083  addConditionalExpansionInstance(clang::Preprocessor &PP, HeaderHandle H,
1084  clang::SourceLocation InstanceLoc,
1085  clang::tok::PPKeywordKind DirectiveKind,
1086  clang::PPCallbacks::ConditionValueKind ConditionValue,
1087  llvm::StringRef ConditionUnexpanded,
1089  // Ignore header guards, assuming the header guard is the only conditional.
1090  if (InNestedHeader)
1091  return;
1092  StringHandle ConditionUnexpandedHandle(addString(ConditionUnexpanded));
1093  PPItemKey InstanceKey(PP, ConditionUnexpandedHandle, H, InstanceLoc);
1094  auto I = ConditionalExpansions.find(InstanceKey);
1095  // If existing instance of condition not found, add one.
1096  if (I == ConditionalExpansions.end()) {
1097  std::string InstanceSourceLine =
1098  getSourceLocationString(PP, InstanceLoc) + ":\n" +
1099  getSourceLine(PP, InstanceLoc) + "\n";
1100  ConditionalExpansions[InstanceKey] =
1101  ConditionalTracker(DirectiveKind, ConditionValue,
1102  ConditionUnexpandedHandle, InclusionPathHandle);
1103  } else {
1104  // We've seen the conditional before. Get its tracker.
1105  ConditionalTracker &CondTracker = I->second;
1106  // Look up an existing instance value for the condition.
1107  ConditionalExpansionInstance *MacroInfo =
1108  CondTracker.findConditionalExpansionInstance(ConditionValue);
1109  // If found, just add the inclusion path to the instance.
1110  if (MacroInfo)
1111  MacroInfo->addInclusionPathHandle(InclusionPathHandle);
1112  else {
1113  // Otherwise add a new instance with the unique value.
1114  CondTracker.addConditionalExpansionInstance(ConditionValue,
1116  }
1117  }
1118  }
1119 
1120  // Report on inconsistent macro instances.
1121  // Returns true if any mismatches.
1122  bool reportInconsistentMacros(llvm::raw_ostream &OS) override {
1123  bool ReturnValue = false;
1124  // Walk all the macro expansion trackers in the map.
1125  for (auto I = MacroExpansions.begin(), E = MacroExpansions.end(); I != E;
1126  ++I) {
1127  const PPItemKey &ItemKey = I->first;
1128  MacroExpansionTracker &MacroExpTracker = I->second;
1129  // If no mismatch (only one instance value) continue.
1130  if (!MacroExpTracker.hasMismatch())
1131  continue;
1132  // Tell caller we found one or more errors.
1133  ReturnValue = true;
1134  // Start the error message.
1135  OS << MacroExpTracker.InstanceSourceLine;
1136  if (ItemKey.Column > 0)
1137  OS << std::string(ItemKey.Column - 1, ' ') << "^\n";
1138  OS << "error: Macro instance '" << MacroExpTracker.MacroUnexpanded
1139  << "' has different values in this header, depending on how it was "
1140  "included.\n";
1141  // Walk all the instances.
1142  for (auto IMT = MacroExpTracker.MacroExpansionInstances.begin(),
1143  EMT = MacroExpTracker.MacroExpansionInstances.end();
1144  IMT != EMT; ++IMT) {
1145  MacroExpansionInstance &MacroInfo = *IMT;
1146  OS << " '" << MacroExpTracker.MacroUnexpanded << "' expanded to: '"
1147  << MacroInfo.MacroExpanded
1148  << "' with respect to these inclusion paths:\n";
1149  // Walk all the inclusion path hierarchies.
1150  for (auto IIP = MacroInfo.InclusionPathHandles.begin(),
1151  EIP = MacroInfo.InclusionPathHandles.end();
1152  IIP != EIP; ++IIP) {
1153  const std::vector<HeaderHandle> &ip = getInclusionPath(*IIP);
1154  auto Count = (int)ip.size();
1155  for (int Index = 0; Index < Count; ++Index) {
1156  HeaderHandle H = ip[Index];
1157  OS << std::string((Index * 2) + 4, ' ') << getHeaderFilePath(H)
1158  << "\n";
1159  }
1160  }
1161  // For a macro that wasn't defined, we flag it by using the
1162  // instance location.
1163  // If there is a definition...
1164  if (MacroInfo.DefinitionLocation.Line != ItemKey.Line) {
1165  OS << MacroInfo.DefinitionSourceLine;
1166  if (MacroInfo.DefinitionLocation.Column > 0)
1167  OS << std::string(MacroInfo.DefinitionLocation.Column - 1, ' ')
1168  << "^\n";
1169  OS << "Macro defined here.\n";
1170  } else
1171  OS << "(no macro definition)"
1172  << "\n";
1173  }
1174  }
1175  return ReturnValue;
1176  }
1177 
1178  // Report on inconsistent conditional instances.
1179  // Returns true if any mismatches.
1180  bool reportInconsistentConditionals(llvm::raw_ostream &OS) override {
1181  bool ReturnValue = false;
1182  // Walk all the conditional trackers in the map.
1183  for (auto I = ConditionalExpansions.begin(),
1184  E = ConditionalExpansions.end();
1185  I != E; ++I) {
1186  const PPItemKey &ItemKey = I->first;
1187  ConditionalTracker &CondTracker = I->second;
1188  if (!CondTracker.hasMismatch())
1189  continue;
1190  // Tell caller we found one or more errors.
1191  ReturnValue = true;
1192  // Start the error message.
1193  OS << HeaderPaths[ItemKey.File] << ":" << ItemKey.Line << ":"
1194  << ItemKey.Column << "\n";
1195  OS << "#" << getDirectiveSpelling(CondTracker.DirectiveKind) << " "
1196  << CondTracker.ConditionUnexpanded << "\n";
1197  OS << "^\n";
1198  OS << "error: Conditional expression instance '"
1199  << CondTracker.ConditionUnexpanded
1200  << "' has different values in this header, depending on how it was "
1201  "included.\n";
1202  // Walk all the instances.
1203  for (auto IMT = CondTracker.ConditionalExpansionInstances.begin(),
1204  EMT = CondTracker.ConditionalExpansionInstances.end();
1205  IMT != EMT; ++IMT) {
1206  ConditionalExpansionInstance &MacroInfo = *IMT;
1207  OS << " '" << CondTracker.ConditionUnexpanded << "' expanded to: '"
1208  << ConditionValueKindStrings[MacroInfo.ConditionValue]
1209  << "' with respect to these inclusion paths:\n";
1210  // Walk all the inclusion path hierarchies.
1211  for (auto IIP = MacroInfo.InclusionPathHandles.begin(),
1212  EIP = MacroInfo.InclusionPathHandles.end();
1213  IIP != EIP; ++IIP) {
1214  const std::vector<HeaderHandle> &ip = getInclusionPath(*IIP);
1215  auto Count = (int)ip.size();
1216  for (int Index = 0; Index < Count; ++Index) {
1217  HeaderHandle H = ip[Index];
1218  OS << std::string((Index * 2) + 4, ' ') << getHeaderFilePath(H)
1219  << "\n";
1220  }
1221  }
1222  }
1223  }
1224  return ReturnValue;
1225  }
1226 
1227  // Get directive spelling.
1228  static const char *getDirectiveSpelling(clang::tok::PPKeywordKind kind) {
1229  switch (kind) {
1230  case clang::tok::pp_if:
1231  return "if";
1232  case clang::tok::pp_elif:
1233  return "elif";
1234  case clang::tok::pp_ifdef:
1235  return "ifdef";
1236  case clang::tok::pp_ifndef:
1237  return "ifndef";
1238  default:
1239  return "(unknown)";
1240  }
1241  }
1242 
1243 private:
1244  llvm::SmallVector<std::string, 32> HeaderList;
1245  // Only do extern, namespace check for headers in HeaderList.
1247  llvm::StringSet<> Strings;
1248  std::vector<StringHandle> HeaderPaths;
1249  std::vector<HeaderHandle> HeaderStack;
1250  std::vector<HeaderInclusionPath> InclusionPaths;
1251  InclusionPathHandle CurrentInclusionPathHandle;
1252  llvm::SmallSet<HeaderHandle, 32> HeadersInThisCompile;
1253  std::vector<PPItemKey> IncludeDirectives;
1254  MacroExpansionMap MacroExpansions;
1255  ConditionalExpansionMap ConditionalExpansions;
1256  bool InNestedHeader;
1257 };
1258 
1259 } // namespace
1260 
1261 // PreprocessorTracker functions.
1262 
1263 // PreprocessorTracker destructor.
1265 
1266 // Create instance of PreprocessorTracker.
1268  llvm::SmallVector<std::string, 32> &Headers,
1269  bool DoBlockCheckHeaderListOnly) {
1270  return new PreprocessorTrackerImpl(Headers, DoBlockCheckHeaderListOnly);
1271 }
1272 
1273 // Preprocessor callbacks for modularize.
1274 
1275 // Handle include directive.
1276 void PreprocessorCallbacks::InclusionDirective(
1277  clang::SourceLocation HashLoc, const clang::Token &IncludeTok,
1278  llvm::StringRef FileName, bool IsAngled,
1279  clang::CharSourceRange FilenameRange, const clang::FileEntry *File,
1280  llvm::StringRef SearchPath, llvm::StringRef RelativePath,
1281  const clang::Module *Imported, clang::SrcMgr::CharacteristicKind FileType) {
1282  int DirectiveLine, DirectiveColumn;
1283  std::string HeaderPath = getSourceLocationFile(PP, HashLoc);
1284  getSourceLocationLineAndColumn(PP, HashLoc, DirectiveLine, DirectiveColumn);
1285  PPTracker.handleIncludeDirective(HeaderPath, DirectiveLine, DirectiveColumn,
1286  FileName);
1287 }
1288 
1289 // Handle file entry/exit.
1290 void PreprocessorCallbacks::FileChanged(
1291  clang::SourceLocation Loc, clang::PPCallbacks::FileChangeReason Reason,
1292  clang::SrcMgr::CharacteristicKind FileType, clang::FileID PrevFID) {
1293  switch (Reason) {
1294  case EnterFile:
1295  PPTracker.handleHeaderEntry(PP, getSourceLocationFile(PP, Loc));
1296  break;
1297  case ExitFile: {
1298  const clang::FileEntry *F =
1299  PP.getSourceManager().getFileEntryForID(PrevFID);
1300  if (F)
1301  PPTracker.handleHeaderExit(F->getName());
1302  } break;
1303  case SystemHeaderPragma:
1304  case RenameFile:
1305  break;
1306  }
1307 }
1308 
1309 // Handle macro expansion.
1310 void PreprocessorCallbacks::MacroExpands(const clang::Token &MacroNameTok,
1311  const clang::MacroDefinition &MD,
1312  clang::SourceRange Range,
1313  const clang::MacroArgs *Args) {
1314  clang::SourceLocation Loc = Range.getBegin();
1315  // Ignore macro argument expansions.
1316  if (!Loc.isFileID())
1317  return;
1318  clang::IdentifierInfo *II = MacroNameTok.getIdentifierInfo();
1319  const clang::MacroInfo *MI = MD.getMacroInfo();
1320  std::string MacroName = II->getName().str();
1321  std::string Unexpanded(getMacroUnexpandedString(Range, PP, MacroName, MI));
1322  std::string Expanded(getMacroExpandedString(PP, MacroName, MI, Args));
1323  PPTracker.addMacroExpansionInstance(
1324  PP, PPTracker.getCurrentHeaderHandle(), Loc, MI->getDefinitionLoc(), II,
1325  Unexpanded, Expanded, PPTracker.getCurrentInclusionPathHandle());
1326 }
1327 
1328 void PreprocessorCallbacks::Defined(const clang::Token &MacroNameTok,
1329  const clang::MacroDefinition &MD,
1330  clang::SourceRange Range) {
1331  clang::SourceLocation Loc(Range.getBegin());
1332  clang::IdentifierInfo *II = MacroNameTok.getIdentifierInfo();
1333  const clang::MacroInfo *MI = MD.getMacroInfo();
1334  std::string MacroName = II->getName().str();
1335  std::string Unexpanded(getSourceString(PP, Range));
1336  PPTracker.addMacroExpansionInstance(
1337  PP, PPTracker.getCurrentHeaderHandle(), Loc,
1338  (MI ? MI->getDefinitionLoc() : Loc), II, Unexpanded,
1339  (MI ? "true" : "false"), PPTracker.getCurrentInclusionPathHandle());
1340 }
1341 
1342 void PreprocessorCallbacks::If(clang::SourceLocation Loc,
1343  clang::SourceRange ConditionRange,
1344  clang::PPCallbacks::ConditionValueKind ConditionResult) {
1345  std::string Unexpanded(getSourceString(PP, ConditionRange));
1346  PPTracker.addConditionalExpansionInstance(
1347  PP, PPTracker.getCurrentHeaderHandle(), Loc, clang::tok::pp_if,
1348  ConditionResult, Unexpanded, PPTracker.getCurrentInclusionPathHandle());
1349 }
1350 
1351 void PreprocessorCallbacks::Elif(clang::SourceLocation Loc,
1352  clang::SourceRange ConditionRange,
1353  clang::PPCallbacks::ConditionValueKind ConditionResult,
1354  clang::SourceLocation IfLoc) {
1355  std::string Unexpanded(getSourceString(PP, ConditionRange));
1356  PPTracker.addConditionalExpansionInstance(
1357  PP, PPTracker.getCurrentHeaderHandle(), Loc, clang::tok::pp_elif,
1358  ConditionResult, Unexpanded, PPTracker.getCurrentInclusionPathHandle());
1359 }
1360 
1361 void PreprocessorCallbacks::Ifdef(clang::SourceLocation Loc,
1362  const clang::Token &MacroNameTok,
1363  const clang::MacroDefinition &MD) {
1364  clang::PPCallbacks::ConditionValueKind IsDefined =
1365  (MD ? clang::PPCallbacks::CVK_True : clang::PPCallbacks::CVK_False );
1366  PPTracker.addConditionalExpansionInstance(
1367  PP, PPTracker.getCurrentHeaderHandle(), Loc, clang::tok::pp_ifdef,
1368  IsDefined, PP.getSpelling(MacroNameTok),
1369  PPTracker.getCurrentInclusionPathHandle());
1370 }
1371 
1372 void PreprocessorCallbacks::Ifndef(clang::SourceLocation Loc,
1373  const clang::Token &MacroNameTok,
1374  const clang::MacroDefinition &MD) {
1375  clang::PPCallbacks::ConditionValueKind IsNotDefined =
1376  (!MD ? clang::PPCallbacks::CVK_True : clang::PPCallbacks::CVK_False );
1377  PPTracker.addConditionalExpansionInstance(
1378  PP, PPTracker.getCurrentHeaderHandle(), Loc, clang::tok::pp_ifndef,
1379  IsNotDefined, PP.getSpelling(MacroNameTok),
1380  PPTracker.getCurrentInclusionPathHandle());
1381 }
1382 } // end namespace Modularize
Range
CharSourceRange Range
SourceRange for the file name.
Definition: IncludeOrderCheck.cpp:38
Modularize::PreprocessorTracker::~PreprocessorTracker
virtual ~PreprocessorTracker()
Definition: PreprocessorTracker.cpp:1264
Modularize::getSourceLocationString
static std::string getSourceLocationString(clang::Preprocessor &PP, clang::SourceLocation Loc)
Definition: PreprocessorTracker.cpp:269
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Definition: PreprocessorTracker.cpp:707
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int InclusionPathHandle
Definition: PreprocessorTracker.cpp:263
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Definition: AvoidBindCheck.cpp:88
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static GeneratorRegistry::Add< MDGenerator > MD(MDGenerator::Format, "Generator for MD output.")
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std::vector< MacroExpansionInstance > MacroExpansionInstances
Definition: PreprocessorTracker.cpp:626
PreprocessorTracker.h
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Definition: PreprocessorTracker.cpp:659
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Definition: PreprocessorTracker.cpp:622
ConditionUnexpanded
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Definition: PreprocessorTracker.cpp:709
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Definition: PreprocessorTracker.cpp:563
MacroUnexpanded
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Definition: PreprocessorTracker.cpp:620
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int HeaderHandle
Definition: PreprocessorTracker.cpp:260
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static std::string getMacroUnexpandedString(clang::SourceRange Range, clang::Preprocessor &PP, llvm::StringRef MacroName, const clang::MacroInfo *MI)
Definition: PreprocessorTracker.cpp:376
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static const char *const ConditionValueKindStrings[]
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llvm::Optional< std::string > getCanonicalPath(const FileEntry *F, const SourceManager &SourceMgr)
Get the canonical path of F.
Definition: SourceCode.cpp:512
ModularizeUtilities.h
Modularize::getSourceString
static std::string getSourceString(clang::Preprocessor &PP, clang::SourceRange Range)
Definition: PreprocessorTracker.cpp:302
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StringHandle DefinitionSourceLine
Definition: PreprocessorTracker.cpp:565
Modularize::getSourceLocationFile
static std::string getSourceLocationFile(clang::Preprocessor &PP, clang::SourceLocation Loc)
Definition: PreprocessorTracker.cpp:278
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Definition: TestIndex.cpp:30
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unsigned DirectiveLine
Definition: Preamble.cpp:131
Name
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Definition: PreprocessorTracker.cpp:511
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std::vector< ConditionalExpansionInstance > ConditionalExpansionInstances
Definition: PreprocessorTracker.cpp:713
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Definition: Dexp.cpp:95
IsAngled
bool IsAngled
true if this was an include with angle brackets
Definition: IncludeOrderCheck.cpp:40
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Definition: FuzzyMatch.h:42
Strings
std::vector< llvm::StringRef > Strings
Definition: Serialization.cpp:195
MacroExpanded
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Definition: PreprocessorTracker.cpp:561
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Definition: PreprocessorTracker.cpp:514
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Definition: TraceTests.cpp:162
Modularize
Definition: CoverageChecker.h:32
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bool operator<(const Ref &L, const Ref &R)
Definition: Ref.h:93
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Definition: PreprocessorTracker.cpp:258
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static PreprocessorTracker * create(llvm::SmallVector< std::string, 32 > &Headers, bool DoBlockCheckHeaderListOnly)
Definition: PreprocessorTracker.cpp:1267
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bool operator==(const Inclusion &LHS, const Inclusion &RHS)
Definition: Headers.cpp:273
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'#' location in the include directive
Definition: IncludeOrderCheck.cpp:37
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static std::string getCanonicalPath(llvm::StringRef FilePath)
Convert header path to canonical form.
Definition: ModularizeUtilities.cpp:455
Modularize::PreprocessorTracker
Preprocessor tracker for modularize.
Definition: PreprocessorTracker.h:41
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static std::string getMacroExpandedString(clang::Preprocessor &PP, llvm::StringRef MacroName, const clang::MacroInfo *MI, const clang::MacroArgs *Args)
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Modularize::getSourceLocationLineAndColumn
static void getSourceLocationLineAndColumn(clang::Preprocessor &PP, clang::SourceLocation Loc, int &Line, int &Column)
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const InclusionPathHandle InclusionPathHandleInvalid
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