1 //===--- ParseAST.cpp - Provide the clang::ParseAST method ----------------===//
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 // This file implements the clang::ParseAST method.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "clang/Parse/ParseAST.h"
15 #include "clang/AST/ASTConsumer.h"
16 #include "clang/AST/ASTContext.h"
17 #include "clang/AST/DeclCXX.h"
18 #include "clang/AST/ExternalASTSource.h"
19 #include "clang/AST/Stmt.h"
20 #include "clang/Parse/ParseDiagnostic.h"
21 #include "clang/Parse/Parser.h"
22 #include "clang/Sema/CodeCompleteConsumer.h"
23 #include "clang/Sema/ExternalSemaSource.h"
24 #include "clang/Sema/Sema.h"
25 #include "clang/Sema/SemaConsumer.h"
26 #include "llvm/Support/CrashRecoveryContext.h"
27 #include <cstdio>
28 #include <memory>
29
30 using namespace clang;
31
32 namespace {
33
34 /// If a crash happens while the parser is active, an entry is printed for it.
35 class PrettyStackTraceParserEntry : public llvm::PrettyStackTraceEntry {
36 const Parser &P;
37 public:
PrettyStackTraceParserEntry(const Parser & p)38 PrettyStackTraceParserEntry(const Parser &p) : P(p) {}
39 void print(raw_ostream &OS) const override;
40 };
41
42 /// If a crash happens while the parser is active, print out a line indicating
43 /// what the current token is.
print(raw_ostream & OS) const44 void PrettyStackTraceParserEntry::print(raw_ostream &OS) const {
45 const Token &Tok = P.getCurToken();
46 if (Tok.is(tok::eof)) {
47 OS << "<eof> parser at end of file\n";
48 return;
49 }
50
51 if (Tok.getLocation().isInvalid()) {
52 OS << "<unknown> parser at unknown location\n";
53 return;
54 }
55
56 const Preprocessor &PP = P.getPreprocessor();
57 Tok.getLocation().print(OS, PP.getSourceManager());
58 if (Tok.isAnnotation()) {
59 OS << ": at annotation token\n";
60 } else {
61 // Do the equivalent of PP.getSpelling(Tok) except for the parts that would
62 // allocate memory.
63 bool Invalid = false;
64 const SourceManager &SM = P.getPreprocessor().getSourceManager();
65 unsigned Length = Tok.getLength();
66 const char *Spelling = SM.getCharacterData(Tok.getLocation(), &Invalid);
67 if (Invalid) {
68 OS << ": unknown current parser token\n";
69 return;
70 }
71 OS << ": current parser token '" << StringRef(Spelling, Length) << "'\n";
72 }
73 }
74
75 } // namespace
76
77 //===----------------------------------------------------------------------===//
78 // Public interface to the file
79 //===----------------------------------------------------------------------===//
80
81 /// ParseAST - Parse the entire file specified, notifying the ASTConsumer as
82 /// the file is parsed. This inserts the parsed decls into the translation unit
83 /// held by Ctx.
84 ///
ParseAST(Preprocessor & PP,ASTConsumer * Consumer,ASTContext & Ctx,bool PrintStats,TranslationUnitKind TUKind,CodeCompleteConsumer * CompletionConsumer,bool SkipFunctionBodies)85 void clang::ParseAST(Preprocessor &PP, ASTConsumer *Consumer,
86 ASTContext &Ctx, bool PrintStats,
87 TranslationUnitKind TUKind,
88 CodeCompleteConsumer *CompletionConsumer,
89 bool SkipFunctionBodies) {
90
91 std::unique_ptr<Sema> S(
92 new Sema(PP, Ctx, *Consumer, TUKind, CompletionConsumer));
93
94 // Recover resources if we crash before exiting this method.
95 llvm::CrashRecoveryContextCleanupRegistrar<Sema> CleanupSema(S.get());
96
97 ParseAST(*S.get(), PrintStats, SkipFunctionBodies);
98 }
99
ParseAST(Sema & S,bool PrintStats,bool SkipFunctionBodies)100 void clang::ParseAST(Sema &S, bool PrintStats, bool SkipFunctionBodies) {
101 // Collect global stats on Decls/Stmts (until we have a module streamer).
102 if (PrintStats) {
103 Decl::EnableStatistics();
104 Stmt::EnableStatistics();
105 }
106
107 // Also turn on collection of stats inside of the Sema object.
108 bool OldCollectStats = PrintStats;
109 std::swap(OldCollectStats, S.CollectStats);
110
111 ASTConsumer *Consumer = &S.getASTConsumer();
112
113 std::unique_ptr<Parser> ParseOP(
114 new Parser(S.getPreprocessor(), S, SkipFunctionBodies));
115 Parser &P = *ParseOP.get();
116
117 PrettyStackTraceParserEntry CrashInfo(P);
118
119 // Recover resources if we crash before exiting this method.
120 llvm::CrashRecoveryContextCleanupRegistrar<Parser>
121 CleanupParser(ParseOP.get());
122
123 S.getPreprocessor().EnterMainSourceFile();
124 P.Initialize();
125
126 // C11 6.9p1 says translation units must have at least one top-level
127 // declaration. C++ doesn't have this restriction. We also don't want to
128 // complain if we have a precompiled header, although technically if the PCH
129 // is empty we should still emit the (pedantic) diagnostic.
130 Parser::DeclGroupPtrTy ADecl;
131 ExternalASTSource *External = S.getASTContext().getExternalSource();
132 if (External)
133 External->StartTranslationUnit(Consumer);
134
135 if (P.ParseTopLevelDecl(ADecl)) {
136 if (!External && !S.getLangOpts().CPlusPlus)
137 P.Diag(diag::ext_empty_translation_unit);
138 } else {
139 do {
140 // If we got a null return and something *was* parsed, ignore it. This
141 // is due to a top-level semicolon, an action override, or a parse error
142 // skipping something.
143 if (ADecl && !Consumer->HandleTopLevelDecl(ADecl.get()))
144 return;
145 } while (!P.ParseTopLevelDecl(ADecl));
146 }
147
148 // Process any TopLevelDecls generated by #pragma weak.
149 for (SmallVectorImpl<Decl *>::iterator
150 I = S.WeakTopLevelDecls().begin(),
151 E = S.WeakTopLevelDecls().end(); I != E; ++I)
152 Consumer->HandleTopLevelDecl(DeclGroupRef(*I));
153
154 Consumer->HandleTranslationUnit(S.getASTContext());
155
156 std::swap(OldCollectStats, S.CollectStats);
157 if (PrintStats) {
158 llvm::errs() << "\nSTATISTICS:\n";
159 P.getActions().PrintStats();
160 S.getASTContext().PrintStats();
161 Decl::PrintStats();
162 Stmt::PrintStats();
163 Consumer->PrintStats();
164 }
165 }
166