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Diffstat (limited to 'contrib/llvm/tools/clang/lib/Lex/Preprocessor.cpp')
| -rw-r--r-- | contrib/llvm/tools/clang/lib/Lex/Preprocessor.cpp | 640 |
1 files changed, 640 insertions, 0 deletions
diff --git a/contrib/llvm/tools/clang/lib/Lex/Preprocessor.cpp b/contrib/llvm/tools/clang/lib/Lex/Preprocessor.cpp new file mode 100644 index 0000000..ce6d9ab --- /dev/null +++ b/contrib/llvm/tools/clang/lib/Lex/Preprocessor.cpp @@ -0,0 +1,640 @@ +//===--- Preprocess.cpp - C Language Family Preprocessor Implementation ---===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file implements the Preprocessor interface. +// +//===----------------------------------------------------------------------===// +// +// Options to support: +// -H - Print the name of each header file used. +// -d[DNI] - Dump various things. +// -fworking-directory - #line's with preprocessor's working dir. +// -fpreprocessed +// -dependency-file,-M,-MM,-MF,-MG,-MP,-MT,-MQ,-MD,-MMD +// -W* +// -w +// +// Messages to emit: +// "Multiple include guards may be useful for:\n" +// +//===----------------------------------------------------------------------===// + +#include "clang/Lex/Preprocessor.h" +#include "MacroArgs.h" +#include "clang/Lex/ExternalPreprocessorSource.h" +#include "clang/Lex/HeaderSearch.h" +#include "clang/Lex/MacroInfo.h" +#include "clang/Lex/Pragma.h" +#include "clang/Lex/PreprocessingRecord.h" +#include "clang/Lex/ScratchBuffer.h" +#include "clang/Lex/LexDiagnostic.h" +#include "clang/Basic/SourceManager.h" +#include "clang/Basic/FileManager.h" +#include "clang/Basic/TargetInfo.h" +#include "llvm/ADT/APFloat.h" +#include "llvm/ADT/SmallVector.h" +#include "llvm/Support/MemoryBuffer.h" +#include "llvm/Support/raw_ostream.h" +using namespace clang; + +//===----------------------------------------------------------------------===// +ExternalPreprocessorSource::~ExternalPreprocessorSource() { } + +Preprocessor::Preprocessor(Diagnostic &diags, const LangOptions &opts, + const TargetInfo &target, SourceManager &SM, + HeaderSearch &Headers, + IdentifierInfoLookup* IILookup, + bool OwnsHeaders) + : Diags(&diags), Features(opts), Target(target),FileMgr(Headers.getFileMgr()), + SourceMgr(SM), HeaderInfo(Headers), ExternalSource(0), + Identifiers(opts, IILookup), BuiltinInfo(Target), CodeCompletionFile(0), + CurPPLexer(0), CurDirLookup(0), Callbacks(0), MacroArgCache(0), Record(0) { + ScratchBuf = new ScratchBuffer(SourceMgr); + CounterValue = 0; // __COUNTER__ starts at 0. + OwnsHeaderSearch = OwnsHeaders; + + // Clear stats. + NumDirectives = NumDefined = NumUndefined = NumPragma = 0; + NumIf = NumElse = NumEndif = 0; + NumEnteredSourceFiles = 0; + NumMacroExpanded = NumFnMacroExpanded = NumBuiltinMacroExpanded = 0; + NumFastMacroExpanded = NumTokenPaste = NumFastTokenPaste = 0; + MaxIncludeStackDepth = 0; + NumSkipped = 0; + + // Default to discarding comments. + KeepComments = false; + KeepMacroComments = false; + + // Macro expansion is enabled. + DisableMacroExpansion = false; + InMacroArgs = false; + NumCachedTokenLexers = 0; + + CachedLexPos = 0; + + // We haven't read anything from the external source. + ReadMacrosFromExternalSource = false; + + // "Poison" __VA_ARGS__, which can only appear in the expansion of a macro. + // This gets unpoisoned where it is allowed. + (Ident__VA_ARGS__ = getIdentifierInfo("__VA_ARGS__"))->setIsPoisoned(); + + // Initialize the pragma handlers. + PragmaHandlers = new PragmaNamespace(0); + RegisterBuiltinPragmas(); + + // Initialize builtin macros like __LINE__ and friends. + RegisterBuiltinMacros(); +} + +Preprocessor::~Preprocessor() { + assert(BacktrackPositions.empty() && "EnableBacktrack/Backtrack imbalance!"); + + while (!IncludeMacroStack.empty()) { + delete IncludeMacroStack.back().TheLexer; + delete IncludeMacroStack.back().TheTokenLexer; + IncludeMacroStack.pop_back(); + } + + // Free any macro definitions. + for (llvm::DenseMap<IdentifierInfo*, MacroInfo*>::iterator I = + Macros.begin(), E = Macros.end(); I != E; ++I) { + // We don't need to free the MacroInfo objects directly. These + // will be released when the BumpPtrAllocator 'BP' object gets + // destroyed. We still need to run the dtor, however, to free + // memory alocated by MacroInfo. + I->second->Destroy(BP); + I->first->setHasMacroDefinition(false); + } + + // Free any cached macro expanders. + for (unsigned i = 0, e = NumCachedTokenLexers; i != e; ++i) + delete TokenLexerCache[i]; + + // Free any cached MacroArgs. + for (MacroArgs *ArgList = MacroArgCache; ArgList; ) + ArgList = ArgList->deallocate(); + + // Release pragma information. + delete PragmaHandlers; + + // Delete the scratch buffer info. + delete ScratchBuf; + + // Delete the header search info, if we own it. + if (OwnsHeaderSearch) + delete &HeaderInfo; + + delete Callbacks; +} + +void Preprocessor::setPTHManager(PTHManager* pm) { + PTH.reset(pm); + FileMgr.addStatCache(PTH->createStatCache()); +} + +void Preprocessor::DumpToken(const Token &Tok, bool DumpFlags) const { + llvm::errs() << tok::getTokenName(Tok.getKind()) << " '" + << getSpelling(Tok) << "'"; + + if (!DumpFlags) return; + + llvm::errs() << "\t"; + if (Tok.isAtStartOfLine()) + llvm::errs() << " [StartOfLine]"; + if (Tok.hasLeadingSpace()) + llvm::errs() << " [LeadingSpace]"; + if (Tok.isExpandDisabled()) + llvm::errs() << " [ExpandDisabled]"; + if (Tok.needsCleaning()) { + const char *Start = SourceMgr.getCharacterData(Tok.getLocation()); + llvm::errs() << " [UnClean='" << std::string(Start, Start+Tok.getLength()) + << "']"; + } + + llvm::errs() << "\tLoc=<"; + DumpLocation(Tok.getLocation()); + llvm::errs() << ">"; +} + +void Preprocessor::DumpLocation(SourceLocation Loc) const { + Loc.dump(SourceMgr); +} + +void Preprocessor::DumpMacro(const MacroInfo &MI) const { + llvm::errs() << "MACRO: "; + for (unsigned i = 0, e = MI.getNumTokens(); i != e; ++i) { + DumpToken(MI.getReplacementToken(i)); + llvm::errs() << " "; + } + llvm::errs() << "\n"; +} + +void Preprocessor::PrintStats() { + llvm::errs() << "\n*** Preprocessor Stats:\n"; + llvm::errs() << NumDirectives << " directives found:\n"; + llvm::errs() << " " << NumDefined << " #define.\n"; + llvm::errs() << " " << NumUndefined << " #undef.\n"; + llvm::errs() << " #include/#include_next/#import:\n"; + llvm::errs() << " " << NumEnteredSourceFiles << " source files entered.\n"; + llvm::errs() << " " << MaxIncludeStackDepth << " max include stack depth\n"; + llvm::errs() << " " << NumIf << " #if/#ifndef/#ifdef.\n"; + llvm::errs() << " " << NumElse << " #else/#elif.\n"; + llvm::errs() << " " << NumEndif << " #endif.\n"; + llvm::errs() << " " << NumPragma << " #pragma.\n"; + llvm::errs() << NumSkipped << " #if/#ifndef#ifdef regions skipped\n"; + + llvm::errs() << NumMacroExpanded << "/" << NumFnMacroExpanded << "/" + << NumBuiltinMacroExpanded << " obj/fn/builtin macros expanded, " + << NumFastMacroExpanded << " on the fast path.\n"; + llvm::errs() << (NumFastTokenPaste+NumTokenPaste) + << " token paste (##) operations performed, " + << NumFastTokenPaste << " on the fast path.\n"; +} + +Preprocessor::macro_iterator +Preprocessor::macro_begin(bool IncludeExternalMacros) const { + if (IncludeExternalMacros && ExternalSource && + !ReadMacrosFromExternalSource) { + ReadMacrosFromExternalSource = true; + ExternalSource->ReadDefinedMacros(); + } + + return Macros.begin(); +} + +Preprocessor::macro_iterator +Preprocessor::macro_end(bool IncludeExternalMacros) const { + if (IncludeExternalMacros && ExternalSource && + !ReadMacrosFromExternalSource) { + ReadMacrosFromExternalSource = true; + ExternalSource->ReadDefinedMacros(); + } + + return Macros.end(); +} + +bool Preprocessor::SetCodeCompletionPoint(const FileEntry *File, + unsigned TruncateAtLine, + unsigned TruncateAtColumn) { + using llvm::MemoryBuffer; + + CodeCompletionFile = File; + + // Okay to clear out the code-completion point by passing NULL. + if (!CodeCompletionFile) + return false; + + // Load the actual file's contents. + bool Invalid = false; + const MemoryBuffer *Buffer = SourceMgr.getMemoryBufferForFile(File, &Invalid); + if (Invalid) + return true; + + // Find the byte position of the truncation point. + const char *Position = Buffer->getBufferStart(); + for (unsigned Line = 1; Line < TruncateAtLine; ++Line) { + for (; *Position; ++Position) { + if (*Position != '\r' && *Position != '\n') + continue; + + // Eat \r\n or \n\r as a single line. + if ((Position[1] == '\r' || Position[1] == '\n') && + Position[0] != Position[1]) + ++Position; + ++Position; + break; + } + } + + Position += TruncateAtColumn - 1; + + // Truncate the buffer. + if (Position < Buffer->getBufferEnd()) { + llvm::StringRef Data(Buffer->getBufferStart(), + Position-Buffer->getBufferStart()); + MemoryBuffer *TruncatedBuffer + = MemoryBuffer::getMemBufferCopy(Data, Buffer->getBufferIdentifier()); + SourceMgr.overrideFileContents(File, TruncatedBuffer); + } + + return false; +} + +bool Preprocessor::isCodeCompletionFile(SourceLocation FileLoc) const { + return CodeCompletionFile && FileLoc.isFileID() && + SourceMgr.getFileEntryForID(SourceMgr.getFileID(FileLoc)) + == CodeCompletionFile; +} + +//===----------------------------------------------------------------------===// +// Token Spelling +//===----------------------------------------------------------------------===// + +/// getSpelling() - Return the 'spelling' of this token. The spelling of a +/// token are the characters used to represent the token in the source file +/// after trigraph expansion and escaped-newline folding. In particular, this +/// wants to get the true, uncanonicalized, spelling of things like digraphs +/// UCNs, etc. +std::string Preprocessor::getSpelling(const Token &Tok, + const SourceManager &SourceMgr, + const LangOptions &Features, + bool *Invalid) { + assert((int)Tok.getLength() >= 0 && "Token character range is bogus!"); + + // If this token contains nothing interesting, return it directly. + bool CharDataInvalid = false; + const char* TokStart = SourceMgr.getCharacterData(Tok.getLocation(), + &CharDataInvalid); + if (Invalid) + *Invalid = CharDataInvalid; + if (CharDataInvalid) + return std::string(); + + if (!Tok.needsCleaning()) + return std::string(TokStart, TokStart+Tok.getLength()); + + std::string Result; + Result.reserve(Tok.getLength()); + + // Otherwise, hard case, relex the characters into the string. + for (const char *Ptr = TokStart, *End = TokStart+Tok.getLength(); + Ptr != End; ) { + unsigned CharSize; + Result.push_back(Lexer::getCharAndSizeNoWarn(Ptr, CharSize, Features)); + Ptr += CharSize; + } + assert(Result.size() != unsigned(Tok.getLength()) && + "NeedsCleaning flag set on something that didn't need cleaning!"); + return Result; +} + +/// getSpelling() - Return the 'spelling' of this token. The spelling of a +/// token are the characters used to represent the token in the source file +/// after trigraph expansion and escaped-newline folding. In particular, this +/// wants to get the true, uncanonicalized, spelling of things like digraphs +/// UCNs, etc. +std::string Preprocessor::getSpelling(const Token &Tok, bool *Invalid) const { + return getSpelling(Tok, SourceMgr, Features, Invalid); +} + +/// getSpelling - This method is used to get the spelling of a token into a +/// preallocated buffer, instead of as an std::string. The caller is required +/// to allocate enough space for the token, which is guaranteed to be at least +/// Tok.getLength() bytes long. The actual length of the token is returned. +/// +/// Note that this method may do two possible things: it may either fill in +/// the buffer specified with characters, or it may *change the input pointer* +/// to point to a constant buffer with the data already in it (avoiding a +/// copy). The caller is not allowed to modify the returned buffer pointer +/// if an internal buffer is returned. +unsigned Preprocessor::getSpelling(const Token &Tok, + const char *&Buffer, bool *Invalid) const { + assert((int)Tok.getLength() >= 0 && "Token character range is bogus!"); + + // If this token is an identifier, just return the string from the identifier + // table, which is very quick. + if (const IdentifierInfo *II = Tok.getIdentifierInfo()) { + Buffer = II->getNameStart(); + return II->getLength(); + } + + // Otherwise, compute the start of the token in the input lexer buffer. + const char *TokStart = 0; + + if (Tok.isLiteral()) + TokStart = Tok.getLiteralData(); + + if (TokStart == 0) { + bool CharDataInvalid = false; + TokStart = SourceMgr.getCharacterData(Tok.getLocation(), &CharDataInvalid); + if (Invalid) + *Invalid = CharDataInvalid; + if (CharDataInvalid) { + Buffer = ""; + return 0; + } + } + + // If this token contains nothing interesting, return it directly. + if (!Tok.needsCleaning()) { + Buffer = TokStart; + return Tok.getLength(); + } + + // Otherwise, hard case, relex the characters into the string. + char *OutBuf = const_cast<char*>(Buffer); + for (const char *Ptr = TokStart, *End = TokStart+Tok.getLength(); + Ptr != End; ) { + unsigned CharSize; + *OutBuf++ = Lexer::getCharAndSizeNoWarn(Ptr, CharSize, Features); + Ptr += CharSize; + } + assert(unsigned(OutBuf-Buffer) != Tok.getLength() && + "NeedsCleaning flag set on something that didn't need cleaning!"); + + return OutBuf-Buffer; +} + +/// getSpelling - This method is used to get the spelling of a token into a +/// SmallVector. Note that the returned StringRef may not point to the +/// supplied buffer if a copy can be avoided. +llvm::StringRef Preprocessor::getSpelling(const Token &Tok, + llvm::SmallVectorImpl<char> &Buffer, + bool *Invalid) const { + // Try the fast path. + if (const IdentifierInfo *II = Tok.getIdentifierInfo()) + return II->getName(); + + // Resize the buffer if we need to copy into it. + if (Tok.needsCleaning()) + Buffer.resize(Tok.getLength()); + + const char *Ptr = Buffer.data(); + unsigned Len = getSpelling(Tok, Ptr, Invalid); + return llvm::StringRef(Ptr, Len); +} + +/// CreateString - Plop the specified string into a scratch buffer and return a +/// location for it. If specified, the source location provides a source +/// location for the token. +void Preprocessor::CreateString(const char *Buf, unsigned Len, Token &Tok, + SourceLocation InstantiationLoc) { + Tok.setLength(Len); + + const char *DestPtr; + SourceLocation Loc = ScratchBuf->getToken(Buf, Len, DestPtr); + + if (InstantiationLoc.isValid()) + Loc = SourceMgr.createInstantiationLoc(Loc, InstantiationLoc, + InstantiationLoc, Len); + Tok.setLocation(Loc); + + // If this is a literal token, set the pointer data. + if (Tok.isLiteral()) + Tok.setLiteralData(DestPtr); +} + + +/// AdvanceToTokenCharacter - Given a location that specifies the start of a +/// token, return a new location that specifies a character within the token. +SourceLocation Preprocessor::AdvanceToTokenCharacter(SourceLocation TokStart, + unsigned CharNo) { + // Figure out how many physical characters away the specified instantiation + // character is. This needs to take into consideration newlines and + // trigraphs. + bool Invalid = false; + const char *TokPtr = SourceMgr.getCharacterData(TokStart, &Invalid); + + // If they request the first char of the token, we're trivially done. + if (Invalid || (CharNo == 0 && Lexer::isObviouslySimpleCharacter(*TokPtr))) + return TokStart; + + unsigned PhysOffset = 0; + + // The usual case is that tokens don't contain anything interesting. Skip + // over the uninteresting characters. If a token only consists of simple + // chars, this method is extremely fast. + while (Lexer::isObviouslySimpleCharacter(*TokPtr)) { + if (CharNo == 0) + return TokStart.getFileLocWithOffset(PhysOffset); + ++TokPtr, --CharNo, ++PhysOffset; + } + + // If we have a character that may be a trigraph or escaped newline, use a + // lexer to parse it correctly. + for (; CharNo; --CharNo) { + unsigned Size; + Lexer::getCharAndSizeNoWarn(TokPtr, Size, Features); + TokPtr += Size; + PhysOffset += Size; + } + + // Final detail: if we end up on an escaped newline, we want to return the + // location of the actual byte of the token. For example foo\<newline>bar + // advanced by 3 should return the location of b, not of \\. One compounding + // detail of this is that the escape may be made by a trigraph. + if (!Lexer::isObviouslySimpleCharacter(*TokPtr)) + PhysOffset += Lexer::SkipEscapedNewLines(TokPtr)-TokPtr; + + return TokStart.getFileLocWithOffset(PhysOffset); +} + +SourceLocation Preprocessor::getLocForEndOfToken(SourceLocation Loc, + unsigned Offset) { + if (Loc.isInvalid() || !Loc.isFileID()) + return SourceLocation(); + + unsigned Len = Lexer::MeasureTokenLength(Loc, getSourceManager(), Features); + if (Len > Offset) + Len = Len - Offset; + else + return Loc; + + return AdvanceToTokenCharacter(Loc, Len); +} + + + +//===----------------------------------------------------------------------===// +// Preprocessor Initialization Methods +//===----------------------------------------------------------------------===// + + +/// EnterMainSourceFile - Enter the specified FileID as the main source file, +/// which implicitly adds the builtin defines etc. +void Preprocessor::EnterMainSourceFile() { + // We do not allow the preprocessor to reenter the main file. Doing so will + // cause FileID's to accumulate information from both runs (e.g. #line + // information) and predefined macros aren't guaranteed to be set properly. + assert(NumEnteredSourceFiles == 0 && "Cannot reenter the main file!"); + FileID MainFileID = SourceMgr.getMainFileID(); + + // Enter the main file source buffer. + EnterSourceFile(MainFileID, 0, SourceLocation()); + + // Tell the header info that the main file was entered. If the file is later + // #imported, it won't be re-entered. + if (const FileEntry *FE = SourceMgr.getFileEntryForID(MainFileID)) + HeaderInfo.IncrementIncludeCount(FE); + + // Preprocess Predefines to populate the initial preprocessor state. + llvm::MemoryBuffer *SB = + llvm::MemoryBuffer::getMemBufferCopy(Predefines, "<built-in>"); + assert(SB && "Cannot fail to create predefined source buffer"); + FileID FID = SourceMgr.createFileIDForMemBuffer(SB); + assert(!FID.isInvalid() && "Could not create FileID for predefines?"); + + // Start parsing the predefines. + EnterSourceFile(FID, 0, SourceLocation()); +} + +void Preprocessor::EndSourceFile() { + // Notify the client that we reached the end of the source file. + if (Callbacks) + Callbacks->EndOfMainFile(); +} + +//===----------------------------------------------------------------------===// +// Lexer Event Handling. +//===----------------------------------------------------------------------===// + +/// LookUpIdentifierInfo - Given a tok::identifier token, look up the +/// identifier information for the token and install it into the token. +IdentifierInfo *Preprocessor::LookUpIdentifierInfo(Token &Identifier, + const char *BufPtr) const { + assert(Identifier.is(tok::identifier) && "Not an identifier!"); + assert(Identifier.getIdentifierInfo() == 0 && "Identinfo already exists!"); + + // Look up this token, see if it is a macro, or if it is a language keyword. + IdentifierInfo *II; + if (BufPtr && !Identifier.needsCleaning()) { + // No cleaning needed, just use the characters from the lexed buffer. + II = getIdentifierInfo(llvm::StringRef(BufPtr, Identifier.getLength())); + } else { + // Cleaning needed, alloca a buffer, clean into it, then use the buffer. + llvm::SmallString<64> IdentifierBuffer; + llvm::StringRef CleanedStr = getSpelling(Identifier, IdentifierBuffer); + II = getIdentifierInfo(CleanedStr); + } + Identifier.setIdentifierInfo(II); + return II; +} + + +/// HandleIdentifier - This callback is invoked when the lexer reads an +/// identifier. This callback looks up the identifier in the map and/or +/// potentially macro expands it or turns it into a named token (like 'for'). +/// +/// Note that callers of this method are guarded by checking the +/// IdentifierInfo's 'isHandleIdentifierCase' bit. If this method changes, the +/// IdentifierInfo methods that compute these properties will need to change to +/// match. +void Preprocessor::HandleIdentifier(Token &Identifier) { + assert(Identifier.getIdentifierInfo() && + "Can't handle identifiers without identifier info!"); + + IdentifierInfo &II = *Identifier.getIdentifierInfo(); + + // If this identifier was poisoned, and if it was not produced from a macro + // expansion, emit an error. + if (II.isPoisoned() && CurPPLexer) { + if (&II != Ident__VA_ARGS__) // We warn about __VA_ARGS__ with poisoning. + Diag(Identifier, diag::err_pp_used_poisoned_id); + else + Diag(Identifier, diag::ext_pp_bad_vaargs_use); + } + + // If this is a macro to be expanded, do it. + if (MacroInfo *MI = getMacroInfo(&II)) { + if (!DisableMacroExpansion && !Identifier.isExpandDisabled()) { + if (MI->isEnabled()) { + if (!HandleMacroExpandedIdentifier(Identifier, MI)) + return; + } else { + // C99 6.10.3.4p2 says that a disabled macro may never again be + // expanded, even if it's in a context where it could be expanded in the + // future. + Identifier.setFlag(Token::DisableExpand); + } + } + } + + // C++ 2.11p2: If this is an alternative representation of a C++ operator, + // then we act as if it is the actual operator and not the textual + // representation of it. + if (II.isCPlusPlusOperatorKeyword()) + Identifier.setIdentifierInfo(0); + + // If this is an extension token, diagnose its use. + // We avoid diagnosing tokens that originate from macro definitions. + // FIXME: This warning is disabled in cases where it shouldn't be, + // like "#define TY typeof", "TY(1) x". + if (II.isExtensionToken() && !DisableMacroExpansion) + Diag(Identifier, diag::ext_token_used); +} + +void Preprocessor::AddCommentHandler(CommentHandler *Handler) { + assert(Handler && "NULL comment handler"); + assert(std::find(CommentHandlers.begin(), CommentHandlers.end(), Handler) == + CommentHandlers.end() && "Comment handler already registered"); + CommentHandlers.push_back(Handler); +} + +void Preprocessor::RemoveCommentHandler(CommentHandler *Handler) { + std::vector<CommentHandler *>::iterator Pos + = std::find(CommentHandlers.begin(), CommentHandlers.end(), Handler); + assert(Pos != CommentHandlers.end() && "Comment handler not registered"); + CommentHandlers.erase(Pos); +} + +bool Preprocessor::HandleComment(Token &result, SourceRange Comment) { + bool AnyPendingTokens = false; + for (std::vector<CommentHandler *>::iterator H = CommentHandlers.begin(), + HEnd = CommentHandlers.end(); + H != HEnd; ++H) { + if ((*H)->HandleComment(*this, Comment)) + AnyPendingTokens = true; + } + if (!AnyPendingTokens || getCommentRetentionState()) + return false; + Lex(result); + return true; +} + +CommentHandler::~CommentHandler() { } + +void Preprocessor::createPreprocessingRecord() { + if (Record) + return; + + Record = new PreprocessingRecord; + addPPCallbacks(Record); +} |
