FrontendAction.cpp revision 208954 
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, ASTUnit *AST) {
29  CurrentFile = Value;
30  CurrentASTUnit.reset(AST);
31}
32
33bool FrontendAction::BeginSourceFile(CompilerInstance &CI,
34                                     llvm::StringRef Filename,
35                                     bool IsAST) {
36  assert(!Instance && "Already processing a source file!");
37  assert(!Filename.empty() && "Unexpected empty filename!");
38  setCurrentFile(Filename);
39  setCompilerInstance(&CI);
40
41  // AST files follow a very different path, since they share objects via the
42  // AST unit.
43  if (IsAST) {
44    assert(!usesPreprocessorOnly() &&
45           "Attempt to pass AST file to preprocessor only action!");
46    assert(hasASTSupport() && "This action does not have AST support!");
47
48    llvm::IntrusiveRefCntPtr<Diagnostic> Diags(&CI.getDiagnostics());
49    std::string Error;
50    ASTUnit *AST = ASTUnit::LoadFromPCHFile(Filename, Diags);
51    if (!AST)
52      goto failure;
53
54    setCurrentFile(Filename, AST);
55
56    // Set the shared objects, these are reset when we finish processing the
57    // file, otherwise the CompilerInstance will happily destroy them.
58    CI.setFileManager(&AST->getFileManager());
59    CI.setSourceManager(&AST->getSourceManager());
60    CI.setPreprocessor(&AST->getPreprocessor());
61    CI.setASTContext(&AST->getASTContext());
62
63    // Initialize the action.
64    if (!BeginSourceFileAction(CI, Filename))
65      goto failure;
66
67    /// Create the AST consumer.
68    CI.setASTConsumer(CreateASTConsumer(CI, Filename));
69    if (!CI.hasASTConsumer())
70      goto failure;
71
72    return true;
73  }
74
75  // Inform the diagnostic client we are processing a source file.
76  CI.getDiagnosticClient().BeginSourceFile(CI.getLangOpts(),
77                                           &CI.getPreprocessor());
78
79  // Initialize the action.
80  if (!BeginSourceFileAction(CI, Filename))
81    goto failure;
82
83  /// Create the AST context and consumer unless this is a preprocessor only
84  /// action.
85  if (!usesPreprocessorOnly()) {
86    CI.createASTContext();
87    CI.setASTConsumer(CreateASTConsumer(CI, Filename));
88    if (!CI.hasASTConsumer())
89      goto failure;
90
91    /// Use PCH?
92    if (!CI.getPreprocessorOpts().ImplicitPCHInclude.empty()) {
93      assert(hasPCHSupport() && "This action does not have PCH support!");
94      CI.createPCHExternalASTSource(
95        CI.getPreprocessorOpts().ImplicitPCHInclude);
96      if (!CI.getASTContext().getExternalSource())
97        goto failure;
98    }
99  }
100
101  // Initialize builtin info as long as we aren't using an external AST
102  // source.
103  if (!CI.hasASTContext() || !CI.getASTContext().getExternalSource()) {
104    Preprocessor &PP = CI.getPreprocessor();
105    PP.getBuiltinInfo().InitializeBuiltins(PP.getIdentifierTable(),
106                                           PP.getLangOptions().NoBuiltin);
107  }
108
109  return true;
110
111  // If we failed, reset state since the client will not end up calling the
112  // matching EndSourceFile().
113  failure:
114  if (isCurrentFileAST()) {
115    CI.takeASTContext();
116    CI.takePreprocessor();
117    CI.takeSourceManager();
118    CI.takeFileManager();
119  }
120
121  CI.getDiagnosticClient().EndSourceFile();
122  setCurrentFile("");
123  setCompilerInstance(0);
124  return false;
125}
126
127void FrontendAction::Execute() {
128  CompilerInstance &CI = getCompilerInstance();
129
130  // Initialize the main file entry. This needs to be delayed until after PCH
131  // has loaded.
132  if (isCurrentFileAST()) {
133    // Set the main file ID to an empty file.
134    //
135    // FIXME: We probably shouldn't need this, but for now this is the
136    // simplest way to reuse the logic in ParseAST.
137    const char *EmptyStr = "";
138    llvm::MemoryBuffer *SB =
139      llvm::MemoryBuffer::getMemBuffer(EmptyStr, "<dummy input>");
140    CI.getSourceManager().createMainFileIDForMemBuffer(SB);
141  } else {
142    if (!CI.InitializeSourceManager(getCurrentFile()))
143      return;
144  }
145
146  if (CI.hasFrontendTimer()) {
147    llvm::TimeRegion Timer(CI.getFrontendTimer());
148    ExecuteAction();
149  }
150  else ExecuteAction();
151}
152
153void FrontendAction::EndSourceFile() {
154  CompilerInstance &CI = getCompilerInstance();
155
156  // Finalize the action.
157  EndSourceFileAction();
158
159  // Release the consumer and the AST, in that order since the consumer may
160  // perform actions in its destructor which require the context.
161  //
162  // FIXME: There is more per-file stuff we could just drop here?
163  if (CI.getFrontendOpts().DisableFree) {
164    CI.takeASTConsumer();
165    if (!isCurrentFileAST())
166      CI.takeASTContext();
167  } else {
168    CI.setASTConsumer(0);
169    if (!isCurrentFileAST())
170      CI.setASTContext(0);
171  }
172
173  // Inform the preprocessor we are done.
174  if (CI.hasPreprocessor())
175    CI.getPreprocessor().EndSourceFile();
176
177  if (CI.getFrontendOpts().ShowStats) {
178    llvm::errs() << "\nSTATISTICS FOR '" << getCurrentFile() << "':\n";
179    CI.getPreprocessor().PrintStats();
180    CI.getPreprocessor().getIdentifierTable().PrintStats();
181    CI.getPreprocessor().getHeaderSearchInfo().PrintStats();
182    CI.getSourceManager().PrintStats();
183    llvm::errs() << "\n";
184  }
185
186  // Cleanup the output streams, and erase the output files if we encountered
187  // an error.
188  CI.clearOutputFiles(/*EraseFiles=*/CI.getDiagnostics().getNumErrors());
189
190  // Inform the diagnostic client we are done with this source file.
191  CI.getDiagnosticClient().EndSourceFile();
192
193  if (isCurrentFileAST()) {
194    CI.takeASTContext();
195    CI.takePreprocessor();
196    CI.takeSourceManager();
197    CI.takeFileManager();
198  }
199
200  setCompilerInstance(0);
201  setCurrentFile("");
202}
203
204//===----------------------------------------------------------------------===//
205// Utility Actions
206//===----------------------------------------------------------------------===//
207
208void ASTFrontendAction::ExecuteAction() {
209  CompilerInstance &CI = getCompilerInstance();
210
211  // FIXME: Move the truncation aspect of this into Sema, we delayed this till
212  // here so the source manager would be initialized.
213  if (hasCodeCompletionSupport() &&
214      !CI.getFrontendOpts().CodeCompletionAt.FileName.empty())
215    CI.createCodeCompletionConsumer();
216
217  // Use a code completion consumer?
218  CodeCompleteConsumer *CompletionConsumer = 0;
219  if (CI.hasCodeCompletionConsumer())
220    CompletionConsumer = &CI.getCodeCompletionConsumer();
221
222  ParseAST(CI.getPreprocessor(), &CI.getASTConsumer(), CI.getASTContext(),
223           CI.getFrontendOpts().ShowStats,
224           usesCompleteTranslationUnit(), CompletionConsumer);
225}
226
227ASTConsumer *
228PreprocessorFrontendAction::CreateASTConsumer(CompilerInstance &CI,
229                                              llvm::StringRef InFile) {
230  llvm_unreachable("Invalid CreateASTConsumer on preprocessor action!");
231}
232