FrontendAction.cpp revision 204962 
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    std::string Error;
49    ASTUnit *AST = ASTUnit::LoadFromPCHFile(Filename, CI.getDiagnostics());
50    if (!AST)
51      goto failure;
52
53    setCurrentFile(Filename, AST);
54
55    // Set the shared objects, these are reset when we finish processing the
56    // file, otherwise the CompilerInstance will happily destroy them.
57    CI.setFileManager(&AST->getFileManager());
58    CI.setSourceManager(&AST->getSourceManager());
59    CI.setPreprocessor(&AST->getPreprocessor());
60    CI.setASTContext(&AST->getASTContext());
61
62    // Initialize the action.
63    if (!BeginSourceFileAction(CI, Filename))
64      goto failure;
65
66    /// Create the AST consumer.
67    CI.setASTConsumer(CreateASTConsumer(CI, Filename));
68    if (!CI.hasASTConsumer())
69      goto failure;
70
71    return true;
72  }
73
74  // Inform the diagnostic client we are processing a source file.
75  CI.getDiagnosticClient().BeginSourceFile(CI.getLangOpts(),
76                                           &CI.getPreprocessor());
77
78  // Initialize the action.
79  if (!BeginSourceFileAction(CI, Filename))
80    goto failure;
81
82  /// Create the AST context and consumer unless this is a preprocessor only
83  /// action.
84  if (!usesPreprocessorOnly()) {
85    CI.createASTContext();
86    CI.setASTConsumer(CreateASTConsumer(CI, Filename));
87    if (!CI.hasASTConsumer())
88      goto failure;
89
90    /// Use PCH?
91    if (!CI.getPreprocessorOpts().ImplicitPCHInclude.empty()) {
92      assert(hasPCHSupport() && "This action does not have PCH support!");
93      CI.createPCHExternalASTSource(
94        CI.getPreprocessorOpts().ImplicitPCHInclude);
95      if (!CI.getASTContext().getExternalSource())
96        goto failure;
97    }
98  }
99
100  // Initialize builtin info as long as we aren't using an external AST
101  // source.
102  if (!CI.hasASTContext() || !CI.getASTContext().getExternalSource()) {
103    Preprocessor &PP = CI.getPreprocessor();
104    PP.getBuiltinInfo().InitializeBuiltins(PP.getIdentifierTable(),
105                                           PP.getLangOptions().NoBuiltin);
106  }
107
108  return true;
109
110  // If we failed, reset state since the client will not end up calling the
111  // matching EndSourceFile().
112  failure:
113  if (isCurrentFileAST()) {
114    CI.takeASTContext();
115    CI.takePreprocessor();
116    CI.takeSourceManager();
117    CI.takeFileManager();
118  }
119
120  CI.getDiagnosticClient().EndSourceFile();
121  setCurrentFile("");
122  setCompilerInstance(0);
123  return false;
124}
125
126void FrontendAction::Execute() {
127  CompilerInstance &CI = getCompilerInstance();
128
129  // Initialize the main file entry. This needs to be delayed until after PCH
130  // has loaded.
131  if (isCurrentFileAST()) {
132    // Set the main file ID to an empty file.
133    //
134    // FIXME: We probably shouldn't need this, but for now this is the
135    // simplest way to reuse the logic in ParseAST.
136    const char *EmptyStr = "";
137    llvm::MemoryBuffer *SB =
138      llvm::MemoryBuffer::getMemBuffer(EmptyStr, EmptyStr, "<dummy input>");
139    CI.getSourceManager().createMainFileIDForMemBuffer(SB);
140  } else {
141    if (!CI.InitializeSourceManager(getCurrentFile()))
142      return;
143  }
144
145  if (CI.hasFrontendTimer()) {
146    llvm::TimeRegion Timer(CI.getFrontendTimer());
147    ExecuteAction();
148  }
149  else ExecuteAction();
150}
151
152void FrontendAction::EndSourceFile() {
153  CompilerInstance &CI = getCompilerInstance();
154
155  // Finalize the action.
156  EndSourceFileAction();
157
158  // Release the consumer and the AST, in that order since the consumer may
159  // perform actions in its destructor which require the context.
160  //
161  // FIXME: There is more per-file stuff we could just drop here?
162  if (CI.getFrontendOpts().DisableFree) {
163    CI.takeASTConsumer();
164    if (!isCurrentFileAST())
165      CI.takeASTContext();
166  } else {
167    CI.setASTConsumer(0);
168    if (!isCurrentFileAST())
169      CI.setASTContext(0);
170  }
171
172  if (CI.getFrontendOpts().ShowStats) {
173    llvm::errs() << "\nSTATISTICS FOR '" << getCurrentFile() << "':\n";
174    CI.getPreprocessor().PrintStats();
175    CI.getPreprocessor().getIdentifierTable().PrintStats();
176    CI.getPreprocessor().getHeaderSearchInfo().PrintStats();
177    CI.getSourceManager().PrintStats();
178    llvm::errs() << "\n";
179  }
180
181  // Cleanup the output streams, and erase the output files if we encountered
182  // an error.
183  CI.clearOutputFiles(/*EraseFiles=*/CI.getDiagnostics().getNumErrors());
184
185  // Inform the diagnostic client we are done with this source file.
186  CI.getDiagnosticClient().EndSourceFile();
187
188  if (isCurrentFileAST()) {
189    CI.takeASTContext();
190    CI.takePreprocessor();
191    CI.takeSourceManager();
192    CI.takeFileManager();
193  }
194
195  setCompilerInstance(0);
196  setCurrentFile("");
197}
198
199//===----------------------------------------------------------------------===//
200// Utility Actions
201//===----------------------------------------------------------------------===//
202
203void ASTFrontendAction::ExecuteAction() {
204  CompilerInstance &CI = getCompilerInstance();
205
206  // FIXME: Move the truncation aspect of this into Sema, we delayed this till
207  // here so the source manager would be initialized.
208  if (hasCodeCompletionSupport() &&
209      !CI.getFrontendOpts().CodeCompletionAt.FileName.empty())
210    CI.createCodeCompletionConsumer();
211
212  // Use a code completion consumer?
213  CodeCompleteConsumer *CompletionConsumer = 0;
214  if (CI.hasCodeCompletionConsumer())
215    CompletionConsumer = &CI.getCodeCompletionConsumer();
216
217  ParseAST(CI.getPreprocessor(), &CI.getASTConsumer(), CI.getASTContext(),
218           CI.getFrontendOpts().ShowStats,
219           usesCompleteTranslationUnit(), CompletionConsumer);
220}
221
222ASTConsumer *
223PreprocessorFrontendAction::CreateASTConsumer(CompilerInstance &CI,
224                                              llvm::StringRef InFile) {
225  llvm_unreachable("Invalid CreateASTConsumer on preprocessor action!");
226}
227