FrontendAction.cpp revision fae3b2f4743dad616623c4df2fdb0f5128bd36d9 
1//===--- FrontendAction.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/FrontendAction.h"
11#include "clang/AST/ASTContext.h"
12#include "clang/Lex/HeaderSearch.h"
13#include "clang/Lex/Preprocessor.h"
14#include "clang/Frontend/ASTUnit.h"
15#include "clang/Frontend/CompilerInstance.h"
16#include "clang/Frontend/FrontendDiagnostic.h"
17#include "clang/Sema/ParseAST.h"
18#include "llvm/Support/MemoryBuffer.h"
19#include "llvm/Support/Timer.h"
20#include "llvm/Support/ErrorHandling.h"
21#include "llvm/Support/raw_ostream.h"
22using namespace clang;
23
24FrontendAction::FrontendAction() : Instance(0) {}
25
26FrontendAction::~FrontendAction() {}
27
28void FrontendAction::setCurrentFile(llvm::StringRef Value, InputKind Kind,
29                                    ASTUnit *AST) {
30  CurrentFile = Value;
31  CurrentFileKind = Kind;
32  CurrentASTUnit.reset(AST);
33}
34
35bool FrontendAction::BeginSourceFile(CompilerInstance &CI,
36                                     llvm::StringRef Filename,
37                                     InputKind InputKind) {
38  assert(!Instance && "Already processing a source file!");
39  assert(!Filename.empty() && "Unexpected empty filename!");
40  setCurrentFile(Filename, InputKind);
41  setCompilerInstance(&CI);
42
43  // AST files follow a very different path, since they share objects via the
44  // AST unit.
45  if (InputKind == IK_AST) {
46    assert(!usesPreprocessorOnly() &&
47           "Attempt to pass AST file to preprocessor only action!");
48    assert(hasASTFileSupport() &&
49           "This action does not have AST file support!");
50
51    llvm::IntrusiveRefCntPtr<Diagnostic> Diags(&CI.getDiagnostics());
52    std::string Error;
53    ASTUnit *AST = ASTUnit::LoadFromPCHFile(Filename, Diags);
54    if (!AST)
55      goto failure;
56
57    setCurrentFile(Filename, InputKind, AST);
58
59    // Set the shared objects, these are reset when we finish processing the
60    // file, otherwise the CompilerInstance will happily destroy them.
61    CI.setFileManager(&AST->getFileManager());
62    CI.setSourceManager(&AST->getSourceManager());
63    CI.setPreprocessor(&AST->getPreprocessor());
64    CI.setASTContext(&AST->getASTContext());
65
66    // Initialize the action.
67    if (!BeginSourceFileAction(CI, Filename))
68      goto failure;
69
70    /// Create the AST consumer.
71    CI.setASTConsumer(CreateASTConsumer(CI, Filename));
72    if (!CI.hasASTConsumer())
73      goto failure;
74
75    return true;
76  }
77
78  // Set up the file and source managers, if needed.
79  if (!CI.hasFileManager())
80    CI.createFileManager();
81  if (!CI.hasSourceManager())
82    CI.createSourceManager();
83
84  // IR files bypass the rest of initialization.
85  if (InputKind == IK_LLVM_IR) {
86    assert(hasIRSupport() &&
87           "This action does not have IR file support!");
88
89    // Inform the diagnostic client we are processing a source file.
90    CI.getDiagnosticClient().BeginSourceFile(CI.getLangOpts(), 0);
91
92    // Initialize the action.
93    if (!BeginSourceFileAction(CI, Filename))
94      goto failure;
95
96    return true;
97  }
98
99  // Set up the preprocessor.
100  CI.createPreprocessor();
101
102  // Inform the diagnostic client we are processing a source file.
103  CI.getDiagnosticClient().BeginSourceFile(CI.getLangOpts(),
104                                           &CI.getPreprocessor());
105
106  // Initialize the action.
107  if (!BeginSourceFileAction(CI, Filename))
108    goto failure;
109
110  /// Create the AST context and consumer unless this is a preprocessor only
111  /// action.
112  if (!usesPreprocessorOnly()) {
113    CI.createASTContext();
114
115    /// Use PCH? If so, we want the PCHReader active before the consumer
116    /// is created, because the consumer might be interested in the reader
117    /// (e.g. the PCH writer for chaining).
118    if (!CI.getPreprocessorOpts().ImplicitPCHInclude.empty()) {
119      assert(hasPCHSupport() && "This action does not have PCH support!");
120      CI.createPCHExternalASTSource(
121                                CI.getPreprocessorOpts().ImplicitPCHInclude,
122                                CI.getPreprocessorOpts().DisablePCHValidation);
123      if (!CI.getASTContext().getExternalSource())
124        goto failure;
125    }
126
127    CI.setASTConsumer(CreateASTConsumer(CI, Filename));
128    if (!CI.hasASTConsumer())
129      goto failure;
130  }
131
132  // Initialize builtin info as long as we aren't using an external AST
133  // source.
134  if (!CI.hasASTContext() || !CI.getASTContext().getExternalSource()) {
135    Preprocessor &PP = CI.getPreprocessor();
136    PP.getBuiltinInfo().InitializeBuiltins(PP.getIdentifierTable(),
137                                           PP.getLangOptions().NoBuiltin);
138  }
139
140  return true;
141
142  // If we failed, reset state since the client will not end up calling the
143  // matching EndSourceFile().
144  failure:
145  if (isCurrentFileAST()) {
146    CI.takeASTContext();
147    CI.takePreprocessor();
148    CI.takeSourceManager();
149    CI.takeFileManager();
150  }
151
152  CI.getDiagnosticClient().EndSourceFile();
153  setCurrentFile("", IK_None);
154  setCompilerInstance(0);
155  return false;
156}
157
158void FrontendAction::Execute() {
159  CompilerInstance &CI = getCompilerInstance();
160
161  // Initialize the main file entry. This needs to be delayed until after PCH
162  // has loaded.
163  if (isCurrentFileAST()) {
164    // Set the main file ID to an empty file.
165    //
166    // FIXME: We probably shouldn't need this, but for now this is the
167    // simplest way to reuse the logic in ParseAST.
168    const char *EmptyStr = "";
169    llvm::MemoryBuffer *SB =
170      llvm::MemoryBuffer::getMemBuffer(EmptyStr, "<dummy input>");
171    CI.getSourceManager().createMainFileIDForMemBuffer(SB);
172  } else {
173    if (!CI.InitializeSourceManager(getCurrentFile()))
174      return;
175  }
176
177  if (CI.hasFrontendTimer()) {
178    llvm::TimeRegion Timer(CI.getFrontendTimer());
179    ExecuteAction();
180  }
181  else ExecuteAction();
182}
183
184void FrontendAction::EndSourceFile() {
185  CompilerInstance &CI = getCompilerInstance();
186
187  // Finalize the action.
188  EndSourceFileAction();
189
190  // Release the consumer and the AST, in that order since the consumer may
191  // perform actions in its destructor which require the context.
192  //
193  // FIXME: There is more per-file stuff we could just drop here?
194  if (CI.getFrontendOpts().DisableFree) {
195    CI.takeASTConsumer();
196    if (!isCurrentFileAST())
197      CI.takeASTContext();
198  } else {
199    CI.setASTConsumer(0);
200    if (!isCurrentFileAST())
201      CI.setASTContext(0);
202  }
203
204  // Inform the preprocessor we are done.
205  if (CI.hasPreprocessor())
206    CI.getPreprocessor().EndSourceFile();
207
208  if (CI.getFrontendOpts().ShowStats) {
209    llvm::errs() << "\nSTATISTICS FOR '" << getCurrentFile() << "':\n";
210    CI.getPreprocessor().PrintStats();
211    CI.getPreprocessor().getIdentifierTable().PrintStats();
212    CI.getPreprocessor().getHeaderSearchInfo().PrintStats();
213    CI.getSourceManager().PrintStats();
214    llvm::errs() << "\n";
215  }
216
217  // Cleanup the output streams, and erase the output files if we encountered
218  // an error.
219  CI.clearOutputFiles(/*EraseFiles=*/CI.getDiagnostics().getNumErrors());
220
221  // Inform the diagnostic client we are done with this source file.
222  CI.getDiagnosticClient().EndSourceFile();
223
224  if (isCurrentFileAST()) {
225    CI.takeASTContext();
226    CI.takePreprocessor();
227    CI.takeSourceManager();
228    CI.takeFileManager();
229  }
230
231  setCompilerInstance(0);
232  setCurrentFile("", IK_None);
233}
234
235//===----------------------------------------------------------------------===//
236// Utility Actions
237//===----------------------------------------------------------------------===//
238
239void ASTFrontendAction::ExecuteAction() {
240  CompilerInstance &CI = getCompilerInstance();
241
242  // FIXME: Move the truncation aspect of this into Sema, we delayed this till
243  // here so the source manager would be initialized.
244  if (hasCodeCompletionSupport() &&
245      !CI.getFrontendOpts().CodeCompletionAt.FileName.empty())
246    CI.createCodeCompletionConsumer();
247
248  // Use a code completion consumer?
249  CodeCompleteConsumer *CompletionConsumer = 0;
250  if (CI.hasCodeCompletionConsumer())
251    CompletionConsumer = &CI.getCodeCompletionConsumer();
252
253  ParseAST(CI.getPreprocessor(), &CI.getASTConsumer(), CI.getASTContext(),
254           CI.getFrontendOpts().ShowStats,
255           usesCompleteTranslationUnit(), CompletionConsumer);
256}
257
258ASTConsumer *
259PreprocessorFrontendAction::CreateASTConsumer(CompilerInstance &CI,
260                                              llvm::StringRef InFile) {
261  llvm_unreachable("Invalid CreateASTConsumer on preprocessor action!");
262}
263