FrontendActions.cpp revision 1432569f88c6da4da902df7571621f3ea3f76596 
1//===--- FrontendActions.cpp ----------------------------------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10#include "clang/Frontend/FrontendActions.h"
11#include "clang/AST/ASTConsumer.h"
12#include "clang/Lex/HeaderSearch.h"
13#include "clang/Lex/Pragma.h"
14#include "clang/Lex/Preprocessor.h"
15#include "clang/Parse/Parser.h"
16#include "clang/Basic/FileManager.h"
17#include "clang/Frontend/ASTConsumers.h"
18#include "clang/Frontend/ASTUnit.h"
19#include "clang/Frontend/CompilerInstance.h"
20#include "clang/Frontend/FrontendDiagnostic.h"
21#include "clang/Frontend/Utils.h"
22#include "clang/Serialization/ASTWriter.h"
23#include "llvm/ADT/OwningPtr.h"
24#include "llvm/Support/MemoryBuffer.h"
25#include "llvm/Support/raw_ostream.h"
26#include "llvm/Support/system_error.h"
27
28using namespace clang;
29
30//===----------------------------------------------------------------------===//
31// Custom Actions
32//===----------------------------------------------------------------------===//
33
34ASTConsumer *InitOnlyAction::CreateASTConsumer(CompilerInstance &CI,
35                                               StringRef InFile) {
36  return new ASTConsumer();
37}
38
39void InitOnlyAction::ExecuteAction() {
40}
41
42//===----------------------------------------------------------------------===//
43// AST Consumer Actions
44//===----------------------------------------------------------------------===//
45
46ASTConsumer *ASTPrintAction::CreateASTConsumer(CompilerInstance &CI,
47                                               StringRef InFile) {
48  if (raw_ostream *OS = CI.createDefaultOutputFile(false, InFile))
49    return CreateASTPrinter(OS);
50  return 0;
51}
52
53ASTConsumer *ASTDumpAction::CreateASTConsumer(CompilerInstance &CI,
54                                              StringRef InFile) {
55  return CreateASTDumper();
56}
57
58ASTConsumer *ASTDumpXMLAction::CreateASTConsumer(CompilerInstance &CI,
59                                                 StringRef InFile) {
60  raw_ostream *OS;
61  if (CI.getFrontendOpts().OutputFile.empty())
62    OS = &llvm::outs();
63  else
64    OS = CI.createDefaultOutputFile(false, InFile);
65  if (!OS) return 0;
66  return CreateASTDumperXML(*OS);
67}
68
69ASTConsumer *ASTViewAction::CreateASTConsumer(CompilerInstance &CI,
70                                              StringRef InFile) {
71  return CreateASTViewer();
72}
73
74ASTConsumer *DeclContextPrintAction::CreateASTConsumer(CompilerInstance &CI,
75                                                       StringRef InFile) {
76  return CreateDeclContextPrinter();
77}
78
79ASTConsumer *GeneratePCHAction::CreateASTConsumer(CompilerInstance &CI,
80                                                  StringRef InFile) {
81  std::string Sysroot;
82  std::string OutputFile;
83  raw_ostream *OS = 0;
84  if (ComputeASTConsumerArguments(CI, InFile, Sysroot, OutputFile, OS))
85    return 0;
86
87  if (!CI.getFrontendOpts().RelocatablePCH)
88    Sysroot.clear();
89  return new PCHGenerator(CI.getPreprocessor(), OutputFile, MakeModule,
90                          Sysroot, OS);
91}
92
93bool GeneratePCHAction::ComputeASTConsumerArguments(CompilerInstance &CI,
94                                                    StringRef InFile,
95                                                    std::string &Sysroot,
96                                                    std::string &OutputFile,
97                                                    raw_ostream *&OS) {
98  Sysroot = CI.getHeaderSearchOpts().Sysroot;
99  if (CI.getFrontendOpts().RelocatablePCH && Sysroot.empty()) {
100    CI.getDiagnostics().Report(diag::err_relocatable_without_isysroot);
101    return true;
102  }
103
104  // We use createOutputFile here because this is exposed via libclang, and we
105  // must disable the RemoveFileOnSignal behavior.
106  // We use a temporary to avoid race conditions.
107  OS = CI.createOutputFile(CI.getFrontendOpts().OutputFile, /*Binary=*/true,
108                           /*RemoveFileOnSignal=*/false, InFile,
109                           /*Extension=*/"", /*useTemporary=*/true);
110  if (!OS)
111    return true;
112
113  OutputFile = CI.getFrontendOpts().OutputFile;
114  return false;
115}
116
117ASTConsumer *GenerateModuleAction::CreateASTConsumer(CompilerInstance &CI,
118                                                     StringRef InFile) {
119  std::string Sysroot;
120  std::string OutputFile;
121  raw_ostream *OS = 0;
122  if (ComputeASTConsumerArguments(CI, InFile, Sysroot, OutputFile, OS))
123    return 0;
124
125  return new PCHGenerator(CI.getPreprocessor(), OutputFile, /*MakeModule=*/true,
126                          Sysroot, OS);
127}
128
129bool GenerateModuleAction::BeginSourceFileAction(CompilerInstance &CI,
130                                                 StringRef Filename) {
131  // Find the module map file.
132  const FileEntry *ModuleMap = CI.getFileManager().getFile(Filename);
133  if (!ModuleMap)  {
134    CI.getDiagnostics().Report(diag::err_module_map_not_found)
135      << Filename;
136    return false;
137  }
138
139  // Parse the module map file.
140  HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
141  if (HS.loadModuleMapFile(ModuleMap))
142    return false;
143
144  if (CI.getLangOpts().CurrentModule.empty()) {
145    CI.getDiagnostics().Report(diag::err_missing_module_name);
146
147    // FIXME: Eventually, we could consider asking whether there was just
148    // a single module described in the module map, and use that as a
149    // default. Then it would be fairly trivial to just "compile" a module
150    // map with a single module (the common case).
151    return false;
152  }
153
154  // Dig out the module definition.
155  ModuleMap::Module *Module = HS.getModule(CI.getLangOpts().CurrentModule,
156                                           /*AllowSearch=*/false);
157  if (!Module) {
158    CI.getDiagnostics().Report(diag::err_missing_module)
159      << CI.getLangOpts().CurrentModule << Filename;
160
161    return false;
162  }
163
164  // If there is an umbrella header, use it as our actual input file.
165  if (Module->UmbrellaHeader) {
166    // FIXME: Deal with explicit submodule headers, which won't be contained
167    // within the umbrella header.
168    setCurrentFile(Module->UmbrellaHeader->getName(), getCurrentFileKind());
169  } else {
170    // FIXME: Deal with the non-umbrella case, where we have to synthesize
171    // a header to parse.
172    // FIXME: Diagnose, at least for now.
173    return false;
174  }
175
176  return true;
177}
178
179bool GenerateModuleAction::ComputeASTConsumerArguments(CompilerInstance &CI,
180                                                       StringRef InFile,
181                                                       std::string &Sysroot,
182                                                       std::string &OutputFile,
183                                                       raw_ostream *&OS) {
184  // If no output file was provided, figure out where this module would go
185  // in the module cache.
186  if (CI.getFrontendOpts().OutputFile.empty()) {
187    HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
188    llvm::SmallString<256> ModuleFileName(HS.getModuleCachePath());
189    llvm::sys::path::append(ModuleFileName,
190                            CI.getLangOpts().CurrentModule + ".pcm");
191    CI.getFrontendOpts().OutputFile = ModuleFileName.str();
192  }
193
194  // We use createOutputFile here because this is exposed via libclang, and we
195  // must disable the RemoveFileOnSignal behavior.
196  // We use a temporary to avoid race conditions.
197  OS = CI.createOutputFile(CI.getFrontendOpts().OutputFile, /*Binary=*/true,
198                           /*RemoveFileOnSignal=*/false, InFile,
199                           /*Extension=*/"", /*useTemporary=*/true);
200  if (!OS)
201    return true;
202
203  OutputFile = CI.getFrontendOpts().OutputFile;
204  return false;
205}
206
207ASTConsumer *SyntaxOnlyAction::CreateASTConsumer(CompilerInstance &CI,
208                                                 StringRef InFile) {
209  return new ASTConsumer();
210}
211
212//===----------------------------------------------------------------------===//
213// Preprocessor Actions
214//===----------------------------------------------------------------------===//
215
216void DumpRawTokensAction::ExecuteAction() {
217  Preprocessor &PP = getCompilerInstance().getPreprocessor();
218  SourceManager &SM = PP.getSourceManager();
219
220  // Start lexing the specified input file.
221  const llvm::MemoryBuffer *FromFile = SM.getBuffer(SM.getMainFileID());
222  Lexer RawLex(SM.getMainFileID(), FromFile, SM, PP.getLangOptions());
223  RawLex.SetKeepWhitespaceMode(true);
224
225  Token RawTok;
226  RawLex.LexFromRawLexer(RawTok);
227  while (RawTok.isNot(tok::eof)) {
228    PP.DumpToken(RawTok, true);
229    llvm::errs() << "\n";
230    RawLex.LexFromRawLexer(RawTok);
231  }
232}
233
234void DumpTokensAction::ExecuteAction() {
235  Preprocessor &PP = getCompilerInstance().getPreprocessor();
236  // Start preprocessing the specified input file.
237  Token Tok;
238  PP.EnterMainSourceFile();
239  do {
240    PP.Lex(Tok);
241    PP.DumpToken(Tok, true);
242    llvm::errs() << "\n";
243  } while (Tok.isNot(tok::eof));
244}
245
246void GeneratePTHAction::ExecuteAction() {
247  CompilerInstance &CI = getCompilerInstance();
248  if (CI.getFrontendOpts().OutputFile.empty() ||
249      CI.getFrontendOpts().OutputFile == "-") {
250    // FIXME: Don't fail this way.
251    // FIXME: Verify that we can actually seek in the given file.
252    llvm::report_fatal_error("PTH requires a seekable file for output!");
253  }
254  llvm::raw_fd_ostream *OS =
255    CI.createDefaultOutputFile(true, getCurrentFile());
256  if (!OS) return;
257
258  CacheTokens(CI.getPreprocessor(), OS);
259}
260
261void PreprocessOnlyAction::ExecuteAction() {
262  Preprocessor &PP = getCompilerInstance().getPreprocessor();
263
264  // Ignore unknown pragmas.
265  PP.AddPragmaHandler(new EmptyPragmaHandler());
266
267  Token Tok;
268  // Start parsing the specified input file.
269  PP.EnterMainSourceFile();
270  do {
271    PP.Lex(Tok);
272  } while (Tok.isNot(tok::eof));
273}
274
275void PrintPreprocessedAction::ExecuteAction() {
276  CompilerInstance &CI = getCompilerInstance();
277  // Output file may need to be set to 'Binary', to avoid converting Unix style
278  // line feeds (<LF>) to Microsoft style line feeds (<CR><LF>).
279  //
280  // Look to see what type of line endings the file uses. If there's a
281  // CRLF, then we won't open the file up in binary mode. If there is
282  // just an LF or CR, then we will open the file up in binary mode.
283  // In this fashion, the output format should match the input format, unless
284  // the input format has inconsistent line endings.
285  //
286  // This should be a relatively fast operation since most files won't have
287  // all of their source code on a single line. However, that is still a
288  // concern, so if we scan for too long, we'll just assume the file should
289  // be opened in binary mode.
290  bool BinaryMode = true;
291  bool InvalidFile = false;
292  const SourceManager& SM = CI.getSourceManager();
293  const llvm::MemoryBuffer *Buffer = SM.getBuffer(SM.getMainFileID(),
294                                                     &InvalidFile);
295  if (!InvalidFile) {
296    const char *cur = Buffer->getBufferStart();
297    const char *end = Buffer->getBufferEnd();
298    const char *next = (cur != end) ? cur + 1 : end;
299
300    // Limit ourselves to only scanning 256 characters into the source
301    // file.  This is mostly a sanity check in case the file has no
302    // newlines whatsoever.
303    if (end - cur > 256) end = cur + 256;
304
305    while (next < end) {
306      if (*cur == 0x0D) {  // CR
307        if (*next == 0x0A)  // CRLF
308          BinaryMode = false;
309
310        break;
311      } else if (*cur == 0x0A)  // LF
312        break;
313
314      ++cur, ++next;
315    }
316  }
317
318  raw_ostream *OS = CI.createDefaultOutputFile(BinaryMode, getCurrentFile());
319  if (!OS) return;
320
321  DoPrintPreprocessedInput(CI.getPreprocessor(), OS,
322                           CI.getPreprocessorOutputOpts());
323}
324
325void PrintPreambleAction::ExecuteAction() {
326  switch (getCurrentFileKind()) {
327  case IK_C:
328  case IK_CXX:
329  case IK_ObjC:
330  case IK_ObjCXX:
331  case IK_OpenCL:
332  case IK_CUDA:
333    break;
334
335  case IK_None:
336  case IK_Asm:
337  case IK_PreprocessedC:
338  case IK_PreprocessedCXX:
339  case IK_PreprocessedObjC:
340  case IK_PreprocessedObjCXX:
341  case IK_AST:
342  case IK_LLVM_IR:
343    // We can't do anything with these.
344    return;
345  }
346
347  CompilerInstance &CI = getCompilerInstance();
348  llvm::MemoryBuffer *Buffer
349      = CI.getFileManager().getBufferForFile(getCurrentFile());
350  if (Buffer) {
351    unsigned Preamble = Lexer::ComputePreamble(Buffer, CI.getLangOpts()).first;
352    llvm::outs().write(Buffer->getBufferStart(), Preamble);
353    delete Buffer;
354  }
355}
356