1 //===--- PrintPreprocessedOutput.cpp - Implement the -E mode --------------===//
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 // This code simply runs the preprocessor on the input file and prints out the
10 // result. This is the traditional behavior of the -E option.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "clang/Frontend/Utils.h"
15 #include "clang/Basic/CharInfo.h"
16 #include "clang/Basic/Diagnostic.h"
17 #include "clang/Basic/SourceManager.h"
18 #include "clang/Frontend/PreprocessorOutputOptions.h"
19 #include "clang/Lex/MacroInfo.h"
20 #include "clang/Lex/PPCallbacks.h"
21 #include "clang/Lex/Pragma.h"
22 #include "clang/Lex/Preprocessor.h"
23 #include "clang/Lex/TokenConcatenation.h"
24 #include "llvm/ADT/STLExtras.h"
25 #include "llvm/ADT/SmallString.h"
26 #include "llvm/ADT/StringRef.h"
27 #include "llvm/Support/ErrorHandling.h"
28 #include "llvm/Support/raw_ostream.h"
29 #include <cstdio>
30 using namespace clang;
31
32 /// PrintMacroDefinition - Print a macro definition in a form that will be
33 /// properly accepted back as a definition.
PrintMacroDefinition(const IdentifierInfo & II,const MacroInfo & MI,Preprocessor & PP,raw_ostream & OS)34 static void PrintMacroDefinition(const IdentifierInfo &II, const MacroInfo &MI,
35 Preprocessor &PP, raw_ostream &OS) {
36 OS << "#define " << II.getName();
37
38 if (MI.isFunctionLike()) {
39 OS << '(';
40 if (!MI.param_empty()) {
41 MacroInfo::param_iterator AI = MI.param_begin(), E = MI.param_end();
42 for (; AI+1 != E; ++AI) {
43 OS << (*AI)->getName();
44 OS << ',';
45 }
46
47 // Last argument.
48 if ((*AI)->getName() == "__VA_ARGS__")
49 OS << "...";
50 else
51 OS << (*AI)->getName();
52 }
53
54 if (MI.isGNUVarargs())
55 OS << "..."; // #define foo(x...)
56
57 OS << ')';
58 }
59
60 // GCC always emits a space, even if the macro body is empty. However, do not
61 // want to emit two spaces if the first token has a leading space.
62 if (MI.tokens_empty() || !MI.tokens_begin()->hasLeadingSpace())
63 OS << ' ';
64
65 SmallString<128> SpellingBuffer;
66 for (const auto &T : MI.tokens()) {
67 if (T.hasLeadingSpace())
68 OS << ' ';
69
70 OS << PP.getSpelling(T, SpellingBuffer);
71 }
72 }
73
74 //===----------------------------------------------------------------------===//
75 // Preprocessed token printer
76 //===----------------------------------------------------------------------===//
77
78 namespace {
79 class PrintPPOutputPPCallbacks : public PPCallbacks {
80 Preprocessor &PP;
81 SourceManager &SM;
82 TokenConcatenation ConcatInfo;
83 public:
84 raw_ostream &OS;
85 private:
86 unsigned CurLine;
87
88 bool EmittedTokensOnThisLine;
89 bool EmittedDirectiveOnThisLine;
90 SrcMgr::CharacteristicKind FileType;
91 SmallString<512> CurFilename;
92 bool Initialized;
93 bool DisableLineMarkers;
94 bool DumpDefines;
95 bool DumpIncludeDirectives;
96 bool UseLineDirectives;
97 bool IsFirstFileEntered;
98 public:
PrintPPOutputPPCallbacks(Preprocessor & pp,raw_ostream & os,bool lineMarkers,bool defines,bool DumpIncludeDirectives,bool UseLineDirectives)99 PrintPPOutputPPCallbacks(Preprocessor &pp, raw_ostream &os, bool lineMarkers,
100 bool defines, bool DumpIncludeDirectives,
101 bool UseLineDirectives)
102 : PP(pp), SM(PP.getSourceManager()), ConcatInfo(PP), OS(os),
103 DisableLineMarkers(lineMarkers), DumpDefines(defines),
104 DumpIncludeDirectives(DumpIncludeDirectives),
105 UseLineDirectives(UseLineDirectives) {
106 CurLine = 0;
107 CurFilename += "<uninit>";
108 EmittedTokensOnThisLine = false;
109 EmittedDirectiveOnThisLine = false;
110 FileType = SrcMgr::C_User;
111 Initialized = false;
112 IsFirstFileEntered = false;
113 }
114
setEmittedTokensOnThisLine()115 void setEmittedTokensOnThisLine() { EmittedTokensOnThisLine = true; }
hasEmittedTokensOnThisLine() const116 bool hasEmittedTokensOnThisLine() const { return EmittedTokensOnThisLine; }
117
setEmittedDirectiveOnThisLine()118 void setEmittedDirectiveOnThisLine() { EmittedDirectiveOnThisLine = true; }
hasEmittedDirectiveOnThisLine() const119 bool hasEmittedDirectiveOnThisLine() const {
120 return EmittedDirectiveOnThisLine;
121 }
122
123 bool startNewLineIfNeeded(bool ShouldUpdateCurrentLine = true);
124
125 void FileChanged(SourceLocation Loc, FileChangeReason Reason,
126 SrcMgr::CharacteristicKind FileType,
127 FileID PrevFID) override;
128 void InclusionDirective(SourceLocation HashLoc, const Token &IncludeTok,
129 StringRef FileName, bool IsAngled,
130 CharSourceRange FilenameRange, const FileEntry *File,
131 StringRef SearchPath, StringRef RelativePath,
132 const Module *Imported,
133 SrcMgr::CharacteristicKind FileType) override;
134 void Ident(SourceLocation Loc, StringRef str) override;
135 void PragmaMessage(SourceLocation Loc, StringRef Namespace,
136 PragmaMessageKind Kind, StringRef Str) override;
137 void PragmaDebug(SourceLocation Loc, StringRef DebugType) override;
138 void PragmaDiagnosticPush(SourceLocation Loc, StringRef Namespace) override;
139 void PragmaDiagnosticPop(SourceLocation Loc, StringRef Namespace) override;
140 void PragmaDiagnostic(SourceLocation Loc, StringRef Namespace,
141 diag::Severity Map, StringRef Str) override;
142 void PragmaWarning(SourceLocation Loc, StringRef WarningSpec,
143 ArrayRef<int> Ids) override;
144 void PragmaWarningPush(SourceLocation Loc, int Level) override;
145 void PragmaWarningPop(SourceLocation Loc) override;
146 void PragmaExecCharsetPush(SourceLocation Loc, StringRef Str) override;
147 void PragmaExecCharsetPop(SourceLocation Loc) override;
148 void PragmaAssumeNonNullBegin(SourceLocation Loc) override;
149 void PragmaAssumeNonNullEnd(SourceLocation Loc) override;
150
151 bool HandleFirstTokOnLine(Token &Tok);
152
153 /// Move to the line of the provided source location. This will
154 /// return true if the output stream required adjustment or if
155 /// the requested location is on the first line.
MoveToLine(SourceLocation Loc)156 bool MoveToLine(SourceLocation Loc) {
157 PresumedLoc PLoc = SM.getPresumedLoc(Loc);
158 if (PLoc.isInvalid())
159 return false;
160 return MoveToLine(PLoc.getLine()) || (PLoc.getLine() == 1);
161 }
162 bool MoveToLine(unsigned LineNo);
163
AvoidConcat(const Token & PrevPrevTok,const Token & PrevTok,const Token & Tok)164 bool AvoidConcat(const Token &PrevPrevTok, const Token &PrevTok,
165 const Token &Tok) {
166 return ConcatInfo.AvoidConcat(PrevPrevTok, PrevTok, Tok);
167 }
168 void WriteLineInfo(unsigned LineNo, const char *Extra=nullptr,
169 unsigned ExtraLen=0);
LineMarkersAreDisabled() const170 bool LineMarkersAreDisabled() const { return DisableLineMarkers; }
171 void HandleNewlinesInToken(const char *TokStr, unsigned Len);
172
173 /// MacroDefined - This hook is called whenever a macro definition is seen.
174 void MacroDefined(const Token &MacroNameTok,
175 const MacroDirective *MD) override;
176
177 /// MacroUndefined - This hook is called whenever a macro #undef is seen.
178 void MacroUndefined(const Token &MacroNameTok,
179 const MacroDefinition &MD,
180 const MacroDirective *Undef) override;
181
182 void BeginModule(const Module *M);
183 void EndModule(const Module *M);
184 };
185 } // end anonymous namespace
186
WriteLineInfo(unsigned LineNo,const char * Extra,unsigned ExtraLen)187 void PrintPPOutputPPCallbacks::WriteLineInfo(unsigned LineNo,
188 const char *Extra,
189 unsigned ExtraLen) {
190 startNewLineIfNeeded(/*ShouldUpdateCurrentLine=*/false);
191
192 // Emit #line directives or GNU line markers depending on what mode we're in.
193 if (UseLineDirectives) {
194 OS << "#line" << ' ' << LineNo << ' ' << '"';
195 OS.write_escaped(CurFilename);
196 OS << '"';
197 } else {
198 OS << '#' << ' ' << LineNo << ' ' << '"';
199 OS.write_escaped(CurFilename);
200 OS << '"';
201
202 if (ExtraLen)
203 OS.write(Extra, ExtraLen);
204
205 if (FileType == SrcMgr::C_System)
206 OS.write(" 3", 2);
207 else if (FileType == SrcMgr::C_ExternCSystem)
208 OS.write(" 3 4", 4);
209 }
210 OS << '\n';
211 }
212
213 /// MoveToLine - Move the output to the source line specified by the location
214 /// object. We can do this by emitting some number of \n's, or be emitting a
215 /// #line directive. This returns false if already at the specified line, true
216 /// if some newlines were emitted.
MoveToLine(unsigned LineNo)217 bool PrintPPOutputPPCallbacks::MoveToLine(unsigned LineNo) {
218 // If this line is "close enough" to the original line, just print newlines,
219 // otherwise print a #line directive.
220 if (LineNo-CurLine <= 8) {
221 if (LineNo-CurLine == 1)
222 OS << '\n';
223 else if (LineNo == CurLine)
224 return false; // Spelling line moved, but expansion line didn't.
225 else {
226 const char *NewLines = "\n\n\n\n\n\n\n\n";
227 OS.write(NewLines, LineNo-CurLine);
228 }
229 } else if (!DisableLineMarkers) {
230 // Emit a #line or line marker.
231 WriteLineInfo(LineNo, nullptr, 0);
232 } else {
233 // Okay, we're in -P mode, which turns off line markers. However, we still
234 // need to emit a newline between tokens on different lines.
235 startNewLineIfNeeded(/*ShouldUpdateCurrentLine=*/false);
236 }
237
238 CurLine = LineNo;
239 return true;
240 }
241
242 bool
startNewLineIfNeeded(bool ShouldUpdateCurrentLine)243 PrintPPOutputPPCallbacks::startNewLineIfNeeded(bool ShouldUpdateCurrentLine) {
244 if (EmittedTokensOnThisLine || EmittedDirectiveOnThisLine) {
245 OS << '\n';
246 EmittedTokensOnThisLine = false;
247 EmittedDirectiveOnThisLine = false;
248 if (ShouldUpdateCurrentLine)
249 ++CurLine;
250 return true;
251 }
252
253 return false;
254 }
255
256 /// FileChanged - Whenever the preprocessor enters or exits a #include file
257 /// it invokes this handler. Update our conception of the current source
258 /// position.
FileChanged(SourceLocation Loc,FileChangeReason Reason,SrcMgr::CharacteristicKind NewFileType,FileID PrevFID)259 void PrintPPOutputPPCallbacks::FileChanged(SourceLocation Loc,
260 FileChangeReason Reason,
261 SrcMgr::CharacteristicKind NewFileType,
262 FileID PrevFID) {
263 // Unless we are exiting a #include, make sure to skip ahead to the line the
264 // #include directive was at.
265 SourceManager &SourceMgr = SM;
266
267 PresumedLoc UserLoc = SourceMgr.getPresumedLoc(Loc);
268 if (UserLoc.isInvalid())
269 return;
270
271 unsigned NewLine = UserLoc.getLine();
272
273 if (Reason == PPCallbacks::EnterFile) {
274 SourceLocation IncludeLoc = UserLoc.getIncludeLoc();
275 if (IncludeLoc.isValid())
276 MoveToLine(IncludeLoc);
277 } else if (Reason == PPCallbacks::SystemHeaderPragma) {
278 // GCC emits the # directive for this directive on the line AFTER the
279 // directive and emits a bunch of spaces that aren't needed. This is because
280 // otherwise we will emit a line marker for THIS line, which requires an
281 // extra blank line after the directive to avoid making all following lines
282 // off by one. We can do better by simply incrementing NewLine here.
283 NewLine += 1;
284 }
285
286 CurLine = NewLine;
287
288 CurFilename.clear();
289 CurFilename += UserLoc.getFilename();
290 FileType = NewFileType;
291
292 if (DisableLineMarkers) {
293 startNewLineIfNeeded(/*ShouldUpdateCurrentLine=*/false);
294 return;
295 }
296
297 if (!Initialized) {
298 WriteLineInfo(CurLine);
299 Initialized = true;
300 }
301
302 // Do not emit an enter marker for the main file (which we expect is the first
303 // entered file). This matches gcc, and improves compatibility with some tools
304 // which track the # line markers as a way to determine when the preprocessed
305 // output is in the context of the main file.
306 if (Reason == PPCallbacks::EnterFile && !IsFirstFileEntered) {
307 IsFirstFileEntered = true;
308 return;
309 }
310
311 switch (Reason) {
312 case PPCallbacks::EnterFile:
313 WriteLineInfo(CurLine, " 1", 2);
314 break;
315 case PPCallbacks::ExitFile:
316 WriteLineInfo(CurLine, " 2", 2);
317 break;
318 case PPCallbacks::SystemHeaderPragma:
319 case PPCallbacks::RenameFile:
320 WriteLineInfo(CurLine);
321 break;
322 }
323 }
324
InclusionDirective(SourceLocation HashLoc,const Token & IncludeTok,StringRef FileName,bool IsAngled,CharSourceRange FilenameRange,const FileEntry * File,StringRef SearchPath,StringRef RelativePath,const Module * Imported,SrcMgr::CharacteristicKind FileType)325 void PrintPPOutputPPCallbacks::InclusionDirective(
326 SourceLocation HashLoc,
327 const Token &IncludeTok,
328 StringRef FileName,
329 bool IsAngled,
330 CharSourceRange FilenameRange,
331 const FileEntry *File,
332 StringRef SearchPath,
333 StringRef RelativePath,
334 const Module *Imported,
335 SrcMgr::CharacteristicKind FileType) {
336 // In -dI mode, dump #include directives prior to dumping their content or
337 // interpretation.
338 if (DumpIncludeDirectives) {
339 startNewLineIfNeeded();
340 MoveToLine(HashLoc);
341 const std::string TokenText = PP.getSpelling(IncludeTok);
342 assert(!TokenText.empty());
343 OS << "#" << TokenText << " "
344 << (IsAngled ? '<' : '"') << FileName << (IsAngled ? '>' : '"')
345 << " /* clang -E -dI */";
346 setEmittedDirectiveOnThisLine();
347 startNewLineIfNeeded();
348 }
349
350 // When preprocessing, turn implicit imports into module import pragmas.
351 if (Imported) {
352 switch (IncludeTok.getIdentifierInfo()->getPPKeywordID()) {
353 case tok::pp_include:
354 case tok::pp_import:
355 case tok::pp_include_next:
356 startNewLineIfNeeded();
357 MoveToLine(HashLoc);
358 OS << "#pragma clang module import " << Imported->getFullModuleName(true)
359 << " /* clang -E: implicit import for "
360 << "#" << PP.getSpelling(IncludeTok) << " "
361 << (IsAngled ? '<' : '"') << FileName << (IsAngled ? '>' : '"')
362 << " */";
363 // Since we want a newline after the pragma, but not a #<line>, start a
364 // new line immediately.
365 EmittedTokensOnThisLine = true;
366 startNewLineIfNeeded();
367 break;
368
369 case tok::pp___include_macros:
370 // #__include_macros has no effect on a user of a preprocessed source
371 // file; the only effect is on preprocessing.
372 //
373 // FIXME: That's not *quite* true: it causes the module in question to
374 // be loaded, which can affect downstream diagnostics.
375 break;
376
377 default:
378 llvm_unreachable("unknown include directive kind");
379 break;
380 }
381 }
382 }
383
384 /// Handle entering the scope of a module during a module compilation.
BeginModule(const Module * M)385 void PrintPPOutputPPCallbacks::BeginModule(const Module *M) {
386 startNewLineIfNeeded();
387 OS << "#pragma clang module begin " << M->getFullModuleName(true);
388 setEmittedDirectiveOnThisLine();
389 }
390
391 /// Handle leaving the scope of a module during a module compilation.
EndModule(const Module * M)392 void PrintPPOutputPPCallbacks::EndModule(const Module *M) {
393 startNewLineIfNeeded();
394 OS << "#pragma clang module end /*" << M->getFullModuleName(true) << "*/";
395 setEmittedDirectiveOnThisLine();
396 }
397
398 /// Ident - Handle #ident directives when read by the preprocessor.
399 ///
Ident(SourceLocation Loc,StringRef S)400 void PrintPPOutputPPCallbacks::Ident(SourceLocation Loc, StringRef S) {
401 MoveToLine(Loc);
402
403 OS.write("#ident ", strlen("#ident "));
404 OS.write(S.begin(), S.size());
405 EmittedTokensOnThisLine = true;
406 }
407
408 /// MacroDefined - This hook is called whenever a macro definition is seen.
MacroDefined(const Token & MacroNameTok,const MacroDirective * MD)409 void PrintPPOutputPPCallbacks::MacroDefined(const Token &MacroNameTok,
410 const MacroDirective *MD) {
411 const MacroInfo *MI = MD->getMacroInfo();
412 // Only print out macro definitions in -dD mode.
413 if (!DumpDefines ||
414 // Ignore __FILE__ etc.
415 MI->isBuiltinMacro()) return;
416
417 MoveToLine(MI->getDefinitionLoc());
418 PrintMacroDefinition(*MacroNameTok.getIdentifierInfo(), *MI, PP, OS);
419 setEmittedDirectiveOnThisLine();
420 }
421
MacroUndefined(const Token & MacroNameTok,const MacroDefinition & MD,const MacroDirective * Undef)422 void PrintPPOutputPPCallbacks::MacroUndefined(const Token &MacroNameTok,
423 const MacroDefinition &MD,
424 const MacroDirective *Undef) {
425 // Only print out macro definitions in -dD mode.
426 if (!DumpDefines) return;
427
428 MoveToLine(MacroNameTok.getLocation());
429 OS << "#undef " << MacroNameTok.getIdentifierInfo()->getName();
430 setEmittedDirectiveOnThisLine();
431 }
432
outputPrintable(raw_ostream & OS,StringRef Str)433 static void outputPrintable(raw_ostream &OS, StringRef Str) {
434 for (unsigned char Char : Str) {
435 if (isPrintable(Char) && Char != '\\' && Char != '"')
436 OS << (char)Char;
437 else // Output anything hard as an octal escape.
438 OS << '\\'
439 << (char)('0' + ((Char >> 6) & 7))
440 << (char)('0' + ((Char >> 3) & 7))
441 << (char)('0' + ((Char >> 0) & 7));
442 }
443 }
444
PragmaMessage(SourceLocation Loc,StringRef Namespace,PragmaMessageKind Kind,StringRef Str)445 void PrintPPOutputPPCallbacks::PragmaMessage(SourceLocation Loc,
446 StringRef Namespace,
447 PragmaMessageKind Kind,
448 StringRef Str) {
449 startNewLineIfNeeded();
450 MoveToLine(Loc);
451 OS << "#pragma ";
452 if (!Namespace.empty())
453 OS << Namespace << ' ';
454 switch (Kind) {
455 case PMK_Message:
456 OS << "message(\"";
457 break;
458 case PMK_Warning:
459 OS << "warning \"";
460 break;
461 case PMK_Error:
462 OS << "error \"";
463 break;
464 }
465
466 outputPrintable(OS, Str);
467 OS << '"';
468 if (Kind == PMK_Message)
469 OS << ')';
470 setEmittedDirectiveOnThisLine();
471 }
472
PragmaDebug(SourceLocation Loc,StringRef DebugType)473 void PrintPPOutputPPCallbacks::PragmaDebug(SourceLocation Loc,
474 StringRef DebugType) {
475 startNewLineIfNeeded();
476 MoveToLine(Loc);
477
478 OS << "#pragma clang __debug ";
479 OS << DebugType;
480
481 setEmittedDirectiveOnThisLine();
482 }
483
484 void PrintPPOutputPPCallbacks::
PragmaDiagnosticPush(SourceLocation Loc,StringRef Namespace)485 PragmaDiagnosticPush(SourceLocation Loc, StringRef Namespace) {
486 startNewLineIfNeeded();
487 MoveToLine(Loc);
488 OS << "#pragma " << Namespace << " diagnostic push";
489 setEmittedDirectiveOnThisLine();
490 }
491
492 void PrintPPOutputPPCallbacks::
PragmaDiagnosticPop(SourceLocation Loc,StringRef Namespace)493 PragmaDiagnosticPop(SourceLocation Loc, StringRef Namespace) {
494 startNewLineIfNeeded();
495 MoveToLine(Loc);
496 OS << "#pragma " << Namespace << " diagnostic pop";
497 setEmittedDirectiveOnThisLine();
498 }
499
PragmaDiagnostic(SourceLocation Loc,StringRef Namespace,diag::Severity Map,StringRef Str)500 void PrintPPOutputPPCallbacks::PragmaDiagnostic(SourceLocation Loc,
501 StringRef Namespace,
502 diag::Severity Map,
503 StringRef Str) {
504 startNewLineIfNeeded();
505 MoveToLine(Loc);
506 OS << "#pragma " << Namespace << " diagnostic ";
507 switch (Map) {
508 case diag::Severity::Remark:
509 OS << "remark";
510 break;
511 case diag::Severity::Warning:
512 OS << "warning";
513 break;
514 case diag::Severity::Error:
515 OS << "error";
516 break;
517 case diag::Severity::Ignored:
518 OS << "ignored";
519 break;
520 case diag::Severity::Fatal:
521 OS << "fatal";
522 break;
523 }
524 OS << " \"" << Str << '"';
525 setEmittedDirectiveOnThisLine();
526 }
527
PragmaWarning(SourceLocation Loc,StringRef WarningSpec,ArrayRef<int> Ids)528 void PrintPPOutputPPCallbacks::PragmaWarning(SourceLocation Loc,
529 StringRef WarningSpec,
530 ArrayRef<int> Ids) {
531 startNewLineIfNeeded();
532 MoveToLine(Loc);
533 OS << "#pragma warning(" << WarningSpec << ':';
534 for (ArrayRef<int>::iterator I = Ids.begin(), E = Ids.end(); I != E; ++I)
535 OS << ' ' << *I;
536 OS << ')';
537 setEmittedDirectiveOnThisLine();
538 }
539
PragmaWarningPush(SourceLocation Loc,int Level)540 void PrintPPOutputPPCallbacks::PragmaWarningPush(SourceLocation Loc,
541 int Level) {
542 startNewLineIfNeeded();
543 MoveToLine(Loc);
544 OS << "#pragma warning(push";
545 if (Level >= 0)
546 OS << ", " << Level;
547 OS << ')';
548 setEmittedDirectiveOnThisLine();
549 }
550
PragmaWarningPop(SourceLocation Loc)551 void PrintPPOutputPPCallbacks::PragmaWarningPop(SourceLocation Loc) {
552 startNewLineIfNeeded();
553 MoveToLine(Loc);
554 OS << "#pragma warning(pop)";
555 setEmittedDirectiveOnThisLine();
556 }
557
PragmaExecCharsetPush(SourceLocation Loc,StringRef Str)558 void PrintPPOutputPPCallbacks::PragmaExecCharsetPush(SourceLocation Loc,
559 StringRef Str) {
560 startNewLineIfNeeded();
561 MoveToLine(Loc);
562 OS << "#pragma character_execution_set(push";
563 if (!Str.empty())
564 OS << ", " << Str;
565 OS << ')';
566 setEmittedDirectiveOnThisLine();
567 }
568
PragmaExecCharsetPop(SourceLocation Loc)569 void PrintPPOutputPPCallbacks::PragmaExecCharsetPop(SourceLocation Loc) {
570 startNewLineIfNeeded();
571 MoveToLine(Loc);
572 OS << "#pragma character_execution_set(pop)";
573 setEmittedDirectiveOnThisLine();
574 }
575
576 void PrintPPOutputPPCallbacks::
PragmaAssumeNonNullBegin(SourceLocation Loc)577 PragmaAssumeNonNullBegin(SourceLocation Loc) {
578 startNewLineIfNeeded();
579 MoveToLine(Loc);
580 OS << "#pragma clang assume_nonnull begin";
581 setEmittedDirectiveOnThisLine();
582 }
583
584 void PrintPPOutputPPCallbacks::
PragmaAssumeNonNullEnd(SourceLocation Loc)585 PragmaAssumeNonNullEnd(SourceLocation Loc) {
586 startNewLineIfNeeded();
587 MoveToLine(Loc);
588 OS << "#pragma clang assume_nonnull end";
589 setEmittedDirectiveOnThisLine();
590 }
591
592 /// HandleFirstTokOnLine - When emitting a preprocessed file in -E mode, this
593 /// is called for the first token on each new line. If this really is the start
594 /// of a new logical line, handle it and return true, otherwise return false.
595 /// This may not be the start of a logical line because the "start of line"
596 /// marker is set for spelling lines, not expansion ones.
HandleFirstTokOnLine(Token & Tok)597 bool PrintPPOutputPPCallbacks::HandleFirstTokOnLine(Token &Tok) {
598 // Figure out what line we went to and insert the appropriate number of
599 // newline characters.
600 if (!MoveToLine(Tok.getLocation()))
601 return false;
602
603 // Print out space characters so that the first token on a line is
604 // indented for easy reading.
605 unsigned ColNo = SM.getExpansionColumnNumber(Tok.getLocation());
606
607 // The first token on a line can have a column number of 1, yet still expect
608 // leading white space, if a macro expansion in column 1 starts with an empty
609 // macro argument, or an empty nested macro expansion. In this case, move the
610 // token to column 2.
611 if (ColNo == 1 && Tok.hasLeadingSpace())
612 ColNo = 2;
613
614 // This hack prevents stuff like:
615 // #define HASH #
616 // HASH define foo bar
617 // From having the # character end up at column 1, which makes it so it
618 // is not handled as a #define next time through the preprocessor if in
619 // -fpreprocessed mode.
620 if (ColNo <= 1 && Tok.is(tok::hash))
621 OS << ' ';
622
623 // Otherwise, indent the appropriate number of spaces.
624 for (; ColNo > 1; --ColNo)
625 OS << ' ';
626
627 return true;
628 }
629
HandleNewlinesInToken(const char * TokStr,unsigned Len)630 void PrintPPOutputPPCallbacks::HandleNewlinesInToken(const char *TokStr,
631 unsigned Len) {
632 unsigned NumNewlines = 0;
633 for (; Len; --Len, ++TokStr) {
634 if (*TokStr != '\n' &&
635 *TokStr != '\r')
636 continue;
637
638 ++NumNewlines;
639
640 // If we have \n\r or \r\n, skip both and count as one line.
641 if (Len != 1 &&
642 (TokStr[1] == '\n' || TokStr[1] == '\r') &&
643 TokStr[0] != TokStr[1]) {
644 ++TokStr;
645 --Len;
646 }
647 }
648
649 if (NumNewlines == 0) return;
650
651 CurLine += NumNewlines;
652 }
653
654
655 namespace {
656 struct UnknownPragmaHandler : public PragmaHandler {
657 const char *Prefix;
658 PrintPPOutputPPCallbacks *Callbacks;
659
660 // Set to true if tokens should be expanded
661 bool ShouldExpandTokens;
662
UnknownPragmaHandler__anon8bd0831c0211::UnknownPragmaHandler663 UnknownPragmaHandler(const char *prefix, PrintPPOutputPPCallbacks *callbacks,
664 bool RequireTokenExpansion)
665 : Prefix(prefix), Callbacks(callbacks),
666 ShouldExpandTokens(RequireTokenExpansion) {}
HandlePragma__anon8bd0831c0211::UnknownPragmaHandler667 void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer,
668 Token &PragmaTok) override {
669 // Figure out what line we went to and insert the appropriate number of
670 // newline characters.
671 Callbacks->startNewLineIfNeeded();
672 Callbacks->MoveToLine(PragmaTok.getLocation());
673 Callbacks->OS.write(Prefix, strlen(Prefix));
674
675 if (ShouldExpandTokens) {
676 // The first token does not have expanded macros. Expand them, if
677 // required.
678 auto Toks = std::make_unique<Token[]>(1);
679 Toks[0] = PragmaTok;
680 PP.EnterTokenStream(std::move(Toks), /*NumToks=*/1,
681 /*DisableMacroExpansion=*/false,
682 /*IsReinject=*/false);
683 PP.Lex(PragmaTok);
684 }
685 Token PrevToken;
686 Token PrevPrevToken;
687 PrevToken.startToken();
688 PrevPrevToken.startToken();
689
690 // Read and print all of the pragma tokens.
691 while (PragmaTok.isNot(tok::eod)) {
692 if (PragmaTok.hasLeadingSpace() ||
693 Callbacks->AvoidConcat(PrevPrevToken, PrevToken, PragmaTok))
694 Callbacks->OS << ' ';
695 std::string TokSpell = PP.getSpelling(PragmaTok);
696 Callbacks->OS.write(&TokSpell[0], TokSpell.size());
697
698 PrevPrevToken = PrevToken;
699 PrevToken = PragmaTok;
700
701 if (ShouldExpandTokens)
702 PP.Lex(PragmaTok);
703 else
704 PP.LexUnexpandedToken(PragmaTok);
705 }
706 Callbacks->setEmittedDirectiveOnThisLine();
707 }
708 };
709 } // end anonymous namespace
710
711
PrintPreprocessedTokens(Preprocessor & PP,Token & Tok,PrintPPOutputPPCallbacks * Callbacks,raw_ostream & OS)712 static void PrintPreprocessedTokens(Preprocessor &PP, Token &Tok,
713 PrintPPOutputPPCallbacks *Callbacks,
714 raw_ostream &OS) {
715 bool DropComments = PP.getLangOpts().TraditionalCPP &&
716 !PP.getCommentRetentionState();
717
718 char Buffer[256];
719 Token PrevPrevTok, PrevTok;
720 PrevPrevTok.startToken();
721 PrevTok.startToken();
722 while (1) {
723 if (Callbacks->hasEmittedDirectiveOnThisLine()) {
724 Callbacks->startNewLineIfNeeded();
725 Callbacks->MoveToLine(Tok.getLocation());
726 }
727
728 // If this token is at the start of a line, emit newlines if needed.
729 if (Tok.isAtStartOfLine() && Callbacks->HandleFirstTokOnLine(Tok)) {
730 // done.
731 } else if (Tok.hasLeadingSpace() ||
732 // If we haven't emitted a token on this line yet, PrevTok isn't
733 // useful to look at and no concatenation could happen anyway.
734 (Callbacks->hasEmittedTokensOnThisLine() &&
735 // Don't print "-" next to "-", it would form "--".
736 Callbacks->AvoidConcat(PrevPrevTok, PrevTok, Tok))) {
737 OS << ' ';
738 }
739
740 if (DropComments && Tok.is(tok::comment)) {
741 // Skip comments. Normally the preprocessor does not generate
742 // tok::comment nodes at all when not keeping comments, but under
743 // -traditional-cpp the lexer keeps /all/ whitespace, including comments.
744 SourceLocation StartLoc = Tok.getLocation();
745 Callbacks->MoveToLine(StartLoc.getLocWithOffset(Tok.getLength()));
746 } else if (Tok.is(tok::eod)) {
747 // Don't print end of directive tokens, since they are typically newlines
748 // that mess up our line tracking. These come from unknown pre-processor
749 // directives or hash-prefixed comments in standalone assembly files.
750 PP.Lex(Tok);
751 continue;
752 } else if (Tok.is(tok::annot_module_include)) {
753 // PrintPPOutputPPCallbacks::InclusionDirective handles producing
754 // appropriate output here. Ignore this token entirely.
755 PP.Lex(Tok);
756 continue;
757 } else if (Tok.is(tok::annot_module_begin)) {
758 // FIXME: We retrieve this token after the FileChanged callback, and
759 // retrieve the module_end token before the FileChanged callback, so
760 // we render this within the file and render the module end outside the
761 // file, but this is backwards from the token locations: the module_begin
762 // token is at the include location (outside the file) and the module_end
763 // token is at the EOF location (within the file).
764 Callbacks->BeginModule(
765 reinterpret_cast<Module *>(Tok.getAnnotationValue()));
766 PP.Lex(Tok);
767 continue;
768 } else if (Tok.is(tok::annot_module_end)) {
769 Callbacks->EndModule(
770 reinterpret_cast<Module *>(Tok.getAnnotationValue()));
771 PP.Lex(Tok);
772 continue;
773 } else if (Tok.is(tok::annot_header_unit)) {
774 // This is a header-name that has been (effectively) converted into a
775 // module-name.
776 // FIXME: The module name could contain non-identifier module name
777 // components. We don't have a good way to round-trip those.
778 Module *M = reinterpret_cast<Module *>(Tok.getAnnotationValue());
779 std::string Name = M->getFullModuleName();
780 OS.write(Name.data(), Name.size());
781 Callbacks->HandleNewlinesInToken(Name.data(), Name.size());
782 } else if (Tok.isAnnotation()) {
783 // Ignore annotation tokens created by pragmas - the pragmas themselves
784 // will be reproduced in the preprocessed output.
785 PP.Lex(Tok);
786 continue;
787 } else if (IdentifierInfo *II = Tok.getIdentifierInfo()) {
788 OS << II->getName();
789 } else if (Tok.isLiteral() && !Tok.needsCleaning() &&
790 Tok.getLiteralData()) {
791 OS.write(Tok.getLiteralData(), Tok.getLength());
792 } else if (Tok.getLength() < llvm::array_lengthof(Buffer)) {
793 const char *TokPtr = Buffer;
794 unsigned Len = PP.getSpelling(Tok, TokPtr);
795 OS.write(TokPtr, Len);
796
797 // Tokens that can contain embedded newlines need to adjust our current
798 // line number.
799 if (Tok.getKind() == tok::comment || Tok.getKind() == tok::unknown)
800 Callbacks->HandleNewlinesInToken(TokPtr, Len);
801 } else {
802 std::string S = PP.getSpelling(Tok);
803 OS.write(S.data(), S.size());
804
805 // Tokens that can contain embedded newlines need to adjust our current
806 // line number.
807 if (Tok.getKind() == tok::comment || Tok.getKind() == tok::unknown)
808 Callbacks->HandleNewlinesInToken(S.data(), S.size());
809 }
810 Callbacks->setEmittedTokensOnThisLine();
811
812 if (Tok.is(tok::eof)) break;
813
814 PrevPrevTok = PrevTok;
815 PrevTok = Tok;
816 PP.Lex(Tok);
817 }
818 }
819
820 typedef std::pair<const IdentifierInfo *, MacroInfo *> id_macro_pair;
MacroIDCompare(const id_macro_pair * LHS,const id_macro_pair * RHS)821 static int MacroIDCompare(const id_macro_pair *LHS, const id_macro_pair *RHS) {
822 return LHS->first->getName().compare(RHS->first->getName());
823 }
824
DoPrintMacros(Preprocessor & PP,raw_ostream * OS)825 static void DoPrintMacros(Preprocessor &PP, raw_ostream *OS) {
826 // Ignore unknown pragmas.
827 PP.IgnorePragmas();
828
829 // -dM mode just scans and ignores all tokens in the files, then dumps out
830 // the macro table at the end.
831 PP.EnterMainSourceFile();
832
833 Token Tok;
834 do PP.Lex(Tok);
835 while (Tok.isNot(tok::eof));
836
837 SmallVector<id_macro_pair, 128> MacrosByID;
838 for (Preprocessor::macro_iterator I = PP.macro_begin(), E = PP.macro_end();
839 I != E; ++I) {
840 auto *MD = I->second.getLatest();
841 if (MD && MD->isDefined())
842 MacrosByID.push_back(id_macro_pair(I->first, MD->getMacroInfo()));
843 }
844 llvm::array_pod_sort(MacrosByID.begin(), MacrosByID.end(), MacroIDCompare);
845
846 for (unsigned i = 0, e = MacrosByID.size(); i != e; ++i) {
847 MacroInfo &MI = *MacrosByID[i].second;
848 // Ignore computed macros like __LINE__ and friends.
849 if (MI.isBuiltinMacro()) continue;
850
851 PrintMacroDefinition(*MacrosByID[i].first, MI, PP, *OS);
852 *OS << '\n';
853 }
854 }
855
856 /// DoPrintPreprocessedInput - This implements -E mode.
857 ///
DoPrintPreprocessedInput(Preprocessor & PP,raw_ostream * OS,const PreprocessorOutputOptions & Opts)858 void clang::DoPrintPreprocessedInput(Preprocessor &PP, raw_ostream *OS,
859 const PreprocessorOutputOptions &Opts) {
860 // Show macros with no output is handled specially.
861 if (!Opts.ShowCPP) {
862 assert(Opts.ShowMacros && "Not yet implemented!");
863 DoPrintMacros(PP, OS);
864 return;
865 }
866
867 // Inform the preprocessor whether we want it to retain comments or not, due
868 // to -C or -CC.
869 PP.SetCommentRetentionState(Opts.ShowComments, Opts.ShowMacroComments);
870
871 PrintPPOutputPPCallbacks *Callbacks = new PrintPPOutputPPCallbacks(
872 PP, *OS, !Opts.ShowLineMarkers, Opts.ShowMacros,
873 Opts.ShowIncludeDirectives, Opts.UseLineDirectives);
874
875 // Expand macros in pragmas with -fms-extensions. The assumption is that
876 // the majority of pragmas in such a file will be Microsoft pragmas.
877 // Remember the handlers we will add so that we can remove them later.
878 std::unique_ptr<UnknownPragmaHandler> MicrosoftExtHandler(
879 new UnknownPragmaHandler(
880 "#pragma", Callbacks,
881 /*RequireTokenExpansion=*/PP.getLangOpts().MicrosoftExt));
882
883 std::unique_ptr<UnknownPragmaHandler> GCCHandler(new UnknownPragmaHandler(
884 "#pragma GCC", Callbacks,
885 /*RequireTokenExpansion=*/PP.getLangOpts().MicrosoftExt));
886
887 std::unique_ptr<UnknownPragmaHandler> ClangHandler(new UnknownPragmaHandler(
888 "#pragma clang", Callbacks,
889 /*RequireTokenExpansion=*/PP.getLangOpts().MicrosoftExt));
890
891 PP.AddPragmaHandler(MicrosoftExtHandler.get());
892 PP.AddPragmaHandler("GCC", GCCHandler.get());
893 PP.AddPragmaHandler("clang", ClangHandler.get());
894
895 // The tokens after pragma omp need to be expanded.
896 //
897 // OpenMP [2.1, Directive format]
898 // Preprocessing tokens following the #pragma omp are subject to macro
899 // replacement.
900 std::unique_ptr<UnknownPragmaHandler> OpenMPHandler(
901 new UnknownPragmaHandler("#pragma omp", Callbacks,
902 /*RequireTokenExpansion=*/true));
903 PP.AddPragmaHandler("omp", OpenMPHandler.get());
904
905 PP.addPPCallbacks(std::unique_ptr<PPCallbacks>(Callbacks));
906
907 // After we have configured the preprocessor, enter the main file.
908 PP.EnterMainSourceFile();
909
910 // Consume all of the tokens that come from the predefines buffer. Those
911 // should not be emitted into the output and are guaranteed to be at the
912 // start.
913 const SourceManager &SourceMgr = PP.getSourceManager();
914 Token Tok;
915 do {
916 PP.Lex(Tok);
917 if (Tok.is(tok::eof) || !Tok.getLocation().isFileID())
918 break;
919
920 PresumedLoc PLoc = SourceMgr.getPresumedLoc(Tok.getLocation());
921 if (PLoc.isInvalid())
922 break;
923
924 if (strcmp(PLoc.getFilename(), "<built-in>"))
925 break;
926 } while (true);
927
928 // Read all the preprocessed tokens, printing them out to the stream.
929 PrintPreprocessedTokens(PP, Tok, Callbacks, *OS);
930 *OS << '\n';
931
932 // Remove the handlers we just added to leave the preprocessor in a sane state
933 // so that it can be reused (for example by a clang::Parser instance).
934 PP.RemovePragmaHandler(MicrosoftExtHandler.get());
935 PP.RemovePragmaHandler("GCC", GCCHandler.get());
936 PP.RemovePragmaHandler("clang", ClangHandler.get());
937 PP.RemovePragmaHandler("omp", OpenMPHandler.get());
938 }
939