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llvm / llvm-project / clang / 650599371b8ccb3750becc342c567474fe95b0d5 / . / Lex / Preprocessor.cpp
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//===--- Preprocess.cpp - C Language Family Preprocessor Implementation ---===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Chris Lattner and 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.
// -C -CC - Do not discard comments for cpp.
// -d[MDNI] - 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 "clang/Lex/MacroInfo.h"
#include "clang/Lex/Pragma.h"
#include "clang/Lex/ScratchBuffer.h"
#include "clang/Basic/Diagnostic.h"
#include "clang/Basic/FileManager.h"
#include "clang/Basic/SourceManager.h"
#include <iostream>
using namespace llvm;
using namespace clang;
//===----------------------------------------------------------------------===//
Preprocessor::Preprocessor(Diagnostic &diags, const LangOptions &opts,
FileManager &FM, SourceManager &SM)
: Diags(diags), Features(opts), FileMgr(FM), SourceMgr(SM),
SystemDirIdx(0), NoCurDirSearch(false),
CurLexer(0), CurDirLookup(0), CurMacroExpander(0) {
ScratchBuf = new ScratchBuffer(SourceMgr);
// Clear stats.
NumDirectives = NumIncluded = NumDefined = NumUndefined = NumPragma = 0;
NumIf = NumElse = NumEndif = 0;
NumEnteredSourceFiles = 0;
NumMacroExpanded = NumFnMacroExpanded = NumBuiltinMacroExpanded = 0;
NumFastMacroExpanded = 0;
MaxIncludeStackDepth = 0; NumMultiIncludeFileOptzn = 0;
NumSkipped = 0;
// Macro expansion is enabled.
DisableMacroExpansion = false;
SkippingContents = false;
InMacroFormalArgs = false;
// There is no file-change handler yet.
FileChangeHandler = 0;
IdentHandler = 0;
// "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() {
// Free any active lexers.
delete CurLexer;
while (!IncludeMacroStack.empty()) {
delete IncludeMacroStack.back().TheLexer;
delete IncludeMacroStack.back().TheMacroExpander;
IncludeMacroStack.pop_back();
}
// Release pragma information.
delete PragmaHandlers;
// Delete the scratch buffer info.
delete ScratchBuf;
}
/// getFileInfo - Return the PerFileInfo structure for the specified
/// FileEntry.
Preprocessor::PerFileInfo &Preprocessor::getFileInfo(const FileEntry *FE) {
if (FE->getUID() >= FileInfo.size())
FileInfo.resize(FE->getUID()+1);
return FileInfo[FE->getUID()];
}
/// AddKeywords - Add all keywords to the symbol table.
///
void Preprocessor::AddKeywords() {
enum {
C90Shift = 0,
EXTC90 = 1 << C90Shift,
NOTC90 = 2 << C90Shift,
C99Shift = 2,
EXTC99 = 1 << C99Shift,
NOTC99 = 2 << C99Shift,
CPPShift = 4,
EXTCPP = 1 << CPPShift,
NOTCPP = 2 << CPPShift,
Mask = 3
};
// Add keywords and tokens for the current language.
#define KEYWORD(NAME, FLAGS) \
AddKeyword(#NAME+1, tok::kw##NAME, \
(FLAGS >> C90Shift) & Mask, \
(FLAGS >> C99Shift) & Mask, \
(FLAGS >> CPPShift) & Mask);
#define ALIAS(NAME, TOK) \
AddKeyword(NAME, tok::kw_ ## TOK, 0, 0, 0);
#include "clang/Basic/TokenKinds.def"
}
/// Diag - Forwarding function for diagnostics. This emits a diagnostic at
/// the specified LexerToken's location, translating the token's start
/// position in the current buffer into a SourcePosition object for rendering.
void Preprocessor::Diag(SourceLocation Loc, unsigned DiagID,
const std::string &Msg) {
// If we are in a '#if 0' block, don't emit any diagnostics for notes,
// warnings or extensions.
if (isSkipping() && Diagnostic::isNoteWarningOrExtension(DiagID))
return;
Diags.Report(Loc, DiagID, Msg);
}
void Preprocessor::DumpToken(const LexerToken &Tok, bool DumpFlags) const {
std::cerr << tok::getTokenName(Tok.getKind()) << " '"
<< getSpelling(Tok) << "'";
if (!DumpFlags) return;
std::cerr << "\t";
if (Tok.isAtStartOfLine())
std::cerr << " [StartOfLine]";
if (Tok.hasLeadingSpace())
std::cerr << " [LeadingSpace]";
if (Tok.needsCleaning()) {
const char *Start = SourceMgr.getCharacterData(Tok.getLocation());
std::cerr << " [UnClean='" << std::string(Start, Start+Tok.getLength())
<< "']";
}
}
void Preprocessor::DumpMacro(const MacroInfo &MI) const {
std::cerr << "MACRO: ";
for (unsigned i = 0, e = MI.getNumTokens(); i != e; ++i) {
DumpToken(MI.getReplacementToken(i));
std::cerr << " ";
}
std::cerr << "\n";
}
void Preprocessor::PrintStats() {
std::cerr << "\n*** Preprocessor Stats:\n";
std::cerr << FileInfo.size() << " files tracked.\n";
unsigned NumOnceOnlyFiles = 0, MaxNumIncludes = 0, NumSingleIncludedFiles = 0;
for (unsigned i = 0, e = FileInfo.size(); i != e; ++i) {
NumOnceOnlyFiles += FileInfo[i].isImport;
if (MaxNumIncludes < FileInfo[i].NumIncludes)
MaxNumIncludes = FileInfo[i].NumIncludes;
NumSingleIncludedFiles += FileInfo[i].NumIncludes == 1;
}
std::cerr << " " << NumOnceOnlyFiles << " #import/#pragma once files.\n";
std::cerr << " " << NumSingleIncludedFiles << " included exactly once.\n";
std::cerr << " " << MaxNumIncludes << " max times a file is included.\n";
std::cerr << NumDirectives << " directives found:\n";
std::cerr << " " << NumDefined << " #define.\n";
std::cerr << " " << NumUndefined << " #undef.\n";
std::cerr << " " << NumIncluded << " #include/#include_next/#import.\n";
std::cerr << " " << NumMultiIncludeFileOptzn << " #includes skipped due to"
<< " the multi-include optimization.\n";
std::cerr << " " << NumEnteredSourceFiles << " source files entered.\n";
std::cerr << " " << MaxIncludeStackDepth << " max include stack depth\n";
std::cerr << " " << NumIf << " #if/#ifndef/#ifdef.\n";
std::cerr << " " << NumElse << " #else/#elif.\n";
std::cerr << " " << NumEndif << " #endif.\n";
std::cerr << " " << NumPragma << " #pragma.\n";
std::cerr << NumSkipped << " #if/#ifndef#ifdef regions skipped\n";
std::cerr << NumMacroExpanded << "/" << NumFnMacroExpanded << "/"
<< NumBuiltinMacroExpanded << " obj/fn/builtin macros expanded, "
<< NumFastMacroExpanded << " on the fast path.\n";
}
//===----------------------------------------------------------------------===//
// 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 LexerToken &Tok) const {
assert((int)Tok.getLength() >= 0 && "Token character range is bogus!");
// If this token contains nothing interesting, return it directly.
const char *TokStart = SourceMgr.getCharacterData(Tok.getLocation());
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 - 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 LexerToken &Tok,
const char *&Buffer) 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->getName();
return Tok.getLength();
}
// Otherwise, compute the start of the token in the input lexer buffer.
const char *TokStart = SourceMgr.getCharacterData(Tok.getLocation());
// 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;
}
//===----------------------------------------------------------------------===//
// Source File Location Methods.
//===----------------------------------------------------------------------===//
/// LookupFile - Given a "foo" or <foo> reference, look up the indicated file,
/// return null on failure. isAngled indicates whether the file reference is
/// for system #include's or not (i.e. using <> instead of "").
const FileEntry *Preprocessor::LookupFile(const std::string &Filename,
bool isAngled,
const DirectoryLookup *FromDir,
const DirectoryLookup *&CurDir) {
assert(CurLexer && "Cannot enter a #include inside a macro expansion!");
CurDir = 0;
// If 'Filename' is absolute, check to see if it exists and no searching.
// FIXME: Portability. This should be a sys::Path interface, this doesn't
// handle things like C:\foo.txt right, nor win32 \\network\device\blah.
if (Filename[0] == '/') {
// If this was an #include_next "/absolute/file", fail.
if (FromDir) return 0;
// Otherwise, just return the file.
return FileMgr.getFile(Filename);
}
// Step #0, unless disabled, check to see if the file is in the #includer's
// directory. This search is not done for <> headers.
if (!isAngled && !FromDir && !NoCurDirSearch) {
unsigned TheFileID = getCurrentFileLexer()->getCurFileID();
const FileEntry *CurFE = SourceMgr.getFileEntryForFileID(TheFileID);
if (CurFE) {
// Concatenate the requested file onto the directory.
// FIXME: Portability. Should be in sys::Path.
if (const FileEntry *FE =
FileMgr.getFile(CurFE->getDir()->getName()+"/"+Filename)) {
if (CurDirLookup)
CurDir = CurDirLookup;
else
CurDir = 0;
// This file is a system header or C++ unfriendly if the old file is.
getFileInfo(FE).DirInfo = getFileInfo(CurFE).DirInfo;
return FE;
}
}
}
// If this is a system #include, ignore the user #include locs.
unsigned i = isAngled ? SystemDirIdx : 0;
// If this is a #include_next request, start searching after the directory the
// file was found in.
if (FromDir)
i = FromDir-&SearchDirs[0];
// Check each directory in sequence to see if it contains this file.
for (; i != SearchDirs.size(); ++i) {
// Concatenate the requested file onto the directory.
// FIXME: Portability. Adding file to dir should be in sys::Path.
std::string SearchDir = SearchDirs[i].getDir()->getName()+"/"+Filename;
if (const FileEntry *FE = FileMgr.getFile(SearchDir)) {
CurDir = &SearchDirs[i];
// This file is a system header or C++ unfriendly if the dir is.
getFileInfo(FE).DirInfo = CurDir->getDirCharacteristic();
return FE;
}
}
// Otherwise, didn't find it.
return 0;
}
/// isInPrimaryFile - Return true if we're in the top-level file, not in a
/// #include.
bool Preprocessor::isInPrimaryFile() const {
if (CurLexer && !CurLexer->Is_PragmaLexer)
return CurLexer->isMainFile();
// If there are any stacked lexers, we're in a #include.
for (unsigned i = 0, e = IncludeMacroStack.size(); i != e; ++i)
if (IncludeMacroStack[i].TheLexer &&
!IncludeMacroStack[i].TheLexer->Is_PragmaLexer)
return IncludeMacroStack[i].TheLexer->isMainFile();
return false;
}
/// getCurrentLexer - Return the current file lexer being lexed from. Note
/// that this ignores any potentially active macro expansions and _Pragma
/// expansions going on at the time.
Lexer *Preprocessor::getCurrentFileLexer() const {
if (CurLexer && !CurLexer->Is_PragmaLexer) return CurLexer;
// Look for a stacked lexer.
for (unsigned i = IncludeMacroStack.size(); i != 0; --i) {
Lexer *L = IncludeMacroStack[i-1].TheLexer;
if (L && !L->Is_PragmaLexer) // Ignore macro & _Pragma expansions.
return L;
}
return 0;
}
/// EnterSourceFile - Add a source file to the top of the include stack and
/// start lexing tokens from it instead of the current buffer. Return true
/// on failure.
void Preprocessor::EnterSourceFile(unsigned FileID,
const DirectoryLookup *CurDir,
bool isMainFile) {
assert(CurMacroExpander == 0 && "Cannot #include a file inside a macro!");
++NumEnteredSourceFiles;
if (MaxIncludeStackDepth < IncludeMacroStack.size())
MaxIncludeStackDepth = IncludeMacroStack.size();
const SourceBuffer *Buffer = SourceMgr.getBuffer(FileID);
Lexer *TheLexer = new Lexer(Buffer, FileID, *this);
if (isMainFile) TheLexer->setIsMainFile();
EnterSourceFileWithLexer(TheLexer, CurDir);
}
/// EnterSourceFile - Add a source file to the top of the include stack and
/// start lexing tokens from it instead of the current buffer.
void Preprocessor::EnterSourceFileWithLexer(Lexer *TheLexer,
const DirectoryLookup *CurDir) {
// Add the current lexer to the include stack.
if (CurLexer || CurMacroExpander)
IncludeMacroStack.push_back(IncludeStackInfo(CurLexer, CurDirLookup,
CurMacroExpander));
CurLexer = TheLexer;
CurDirLookup = CurDir;
CurMacroExpander = 0;
// Notify the client, if desired, that we are in a new source file.
if (FileChangeHandler && !CurLexer->Is_PragmaLexer) {
DirectoryLookup::DirType FileType = DirectoryLookup::NormalHeaderDir;
// Get the file entry for the current file.
if (const FileEntry *FE =
SourceMgr.getFileEntryForFileID(CurLexer->getCurFileID()))
FileType = getFileInfo(FE).DirInfo;
FileChangeHandler(SourceLocation(CurLexer->getCurFileID(), 0),
EnterFile, FileType);
}
}
/// EnterMacro - Add a Macro to the top of the include stack and start lexing
/// tokens from it instead of the current buffer.
void Preprocessor::EnterMacro(LexerToken &Tok, MacroFormalArgs *Formals) {
IdentifierInfo *Identifier = Tok.getIdentifierInfo();
MacroInfo &MI = *Identifier->getMacroInfo();
IncludeMacroStack.push_back(IncludeStackInfo(CurLexer, CurDirLookup,
CurMacroExpander));
CurLexer = 0;
CurDirLookup = 0;
// Mark the macro as currently disabled, so that it is not recursively
// expanded.
MI.DisableMacro();
CurMacroExpander = new MacroExpander(Tok, Formals, *this);
}
//===----------------------------------------------------------------------===//
// Macro Expansion Handling.
//===----------------------------------------------------------------------===//
/// RegisterBuiltinMacro - Register the specified identifier in the identifier
/// table and mark it as a builtin macro to be expanded.
IdentifierInfo *Preprocessor::RegisterBuiltinMacro(const char *Name) {
// Get the identifier.
IdentifierInfo *Id = getIdentifierInfo(Name);
// Mark it as being a macro that is builtin.
MacroInfo *MI = new MacroInfo(SourceLocation());
MI->setIsBuiltinMacro();
Id->setMacroInfo(MI);
return Id;
}
/// RegisterBuiltinMacros - Register builtin macros, such as __LINE__ with the
/// identifier table.
void Preprocessor::RegisterBuiltinMacros() {
Ident__LINE__ = RegisterBuiltinMacro("__LINE__");
Ident__FILE__ = RegisterBuiltinMacro("__FILE__");
Ident__DATE__ = RegisterBuiltinMacro("__DATE__");
Ident__TIME__ = RegisterBuiltinMacro("__TIME__");
Ident_Pragma = RegisterBuiltinMacro("_Pragma");
// GCC Extensions.
Ident__BASE_FILE__ = RegisterBuiltinMacro("__BASE_FILE__");
Ident__INCLUDE_LEVEL__ = RegisterBuiltinMacro("__INCLUDE_LEVEL__");
Ident__TIMESTAMP__ = RegisterBuiltinMacro("__TIMESTAMP__");
}
/// isTrivialSingleTokenExpansion - Return true if MI, which has a single token
/// in its expansion, currently expands to that token literally.
static bool isTrivialSingleTokenExpansion(const MacroInfo *MI,
const IdentifierInfo *MacroIdent) {
IdentifierInfo *II = MI->getReplacementToken(0).getIdentifierInfo();
// If the token isn't an identifier, it's always literally expanded.
if (II == 0) return true;
// If the identifier is a macro, and if that macro is enabled, it may be
// expanded so it's not a trivial expansion.
if (II->getMacroInfo() && II->getMacroInfo()->isEnabled() &&
// Fast expanding "#define X X" is ok, because X would be disabled.
II != MacroIdent)
return false;
// If this is an object-like macro invocation, it is safe to trivially expand
// it.
if (MI->isObjectLike()) return true;
// If this is a function-like macro invocation, it's safe to trivially expand
// as long as the identifier is not a macro argument.
for (MacroInfo::arg_iterator I = MI->arg_begin(), E = MI->arg_end();
I != E; ++I)
if (*I == II)
return false; // Identifier is a macro argument.
return true;
}
/// HandleMacroExpandedIdentifier - If an identifier token is read that is to be
/// expanded as a macro, handle it and return the next token as 'Identifier'.
bool Preprocessor::HandleMacroExpandedIdentifier(LexerToken &Identifier,
MacroInfo *MI) {
// If this is a builtin macro, like __LINE__ or _Pragma, handle it specially.
if (MI->isBuiltinMacro()) {
ExpandBuiltinMacro(Identifier);
return false;
}
/// FormalArgs - If this is a function-like macro expansion, this contains,
/// for each macro argument, the list of tokens that were provided to the
/// invocation.
MacroFormalArgs *FormalArgs = 0;
// If this is a function-like macro, read the arguments.
if (MI->isFunctionLike()) {
// FIXME: We need to query to see if the ( exists without reading it.
// C99 6.10.3p10: If the preprocessing token immediately after the the macro
// name isn't a '(', this macro should not be expanded.
bool isFunctionInvocation = true;
if (!isFunctionInvocation)
return true;
LexerToken Tok;
LexUnexpandedToken(Tok);
assert(Tok.getKind() == tok::l_paren &&
"not a function-like macro invocation!");
// Remember that we are now parsing the arguments to a macro invocation.
// Preprocessor directives used inside macro arguments are not portable, and
// this enables the warning.
InMacroFormalArgs = true;
FormalArgs = ReadFunctionLikeMacroFormalArgs(Identifier, MI);
// Finished parsing args.
InMacroFormalArgs = false;
// If there was an error parsing the arguments, bail out.
if (FormalArgs == 0) return false;
++NumFnMacroExpanded;
} else {
++NumMacroExpanded;
}
// Notice that this macro has been used.
MI->setIsUsed(true);
// If we started lexing a macro, enter the macro expansion body.
// If this macro expands to no tokens, don't bother to push it onto the
// expansion stack, only to take it right back off.
if (MI->getNumTokens() == 0) {
// No need for formal arg info.
delete FormalArgs;
// Ignore this macro use, just return the next token in the current
// buffer.
bool HadLeadingSpace = Identifier.hasLeadingSpace();
bool IsAtStartOfLine = Identifier.isAtStartOfLine();
Lex(Identifier);
// If the identifier isn't on some OTHER line, inherit the leading
// whitespace/first-on-a-line property of this token. This handles
// stuff like "! XX," -> "! ," and " XX," -> " ,", when XX is
// empty.
if (!Identifier.isAtStartOfLine()) {
if (IsAtStartOfLine) Identifier.SetFlag(LexerToken::StartOfLine);
if (HadLeadingSpace) Identifier.SetFlag(LexerToken::LeadingSpace);
}
++NumFastMacroExpanded;
return false;
} else if (MI->getNumTokens() == 1 &&
isTrivialSingleTokenExpansion(MI, Identifier.getIdentifierInfo())){
// Otherwise, if this macro expands into a single trivially-expanded
// token: expand it now. This handles common cases like
// "#define VAL 42".
// Propagate the isAtStartOfLine/hasLeadingSpace markers of the macro
// identifier to the expanded token.
bool isAtStartOfLine = Identifier.isAtStartOfLine();
bool hasLeadingSpace = Identifier.hasLeadingSpace();
// Remember where the token is instantiated.
SourceLocation InstantiateLoc = Identifier.getLocation();
// Replace the result token.
Identifier = MI->getReplacementToken(0);
// Restore the StartOfLine/LeadingSpace markers.
Identifier.SetFlagValue(LexerToken::StartOfLine , isAtStartOfLine);
Identifier.SetFlagValue(LexerToken::LeadingSpace, hasLeadingSpace);
// Update the tokens location to include both its logical and physical
// locations.
SourceLocation Loc =
SourceMgr.getInstantiationLoc(Identifier.getLocation(), InstantiateLoc);
Identifier.SetLocation(Loc);
// Since this is not an identifier token, it can't be macro expanded, so
// we're done.
++NumFastMacroExpanded;
return false;
}
// Start expanding the macro.
EnterMacro(Identifier, FormalArgs);
// Now that the macro is at the top of the include stack, ask the
// preprocessor to read the next token from it.
Lex(Identifier);
return false;
}
/// ReadFunctionLikeMacroFormalArgs - After reading "MACRO(", this method is
/// invoked to read all of the formal arguments specified for the macro
/// invocation. This returns null on error.
MacroFormalArgs *Preprocessor::
ReadFunctionLikeMacroFormalArgs(LexerToken &MacroName, MacroInfo *MI) {
// Use an auto_ptr here so that the MacroFormalArgs object is deleted on
// all error paths.
std::auto_ptr<MacroFormalArgs> Args(new MacroFormalArgs(MI));
// The number of fixed arguments to parse.
unsigned NumFixedArgsLeft = MI->getNumArgs();
bool isVariadic = MI->isVariadic();
// If this is a C99-style varargs macro invocation, add an extra expected
// argument, which will catch all of the varargs formals in one argument.
if (MI->isC99Varargs())
++NumFixedArgsLeft;
// Outer loop, while there are more arguments, keep reading them.
LexerToken Tok;
Tok.SetKind(tok::comma);
--NumFixedArgsLeft; // Start reading the first arg.
while (Tok.getKind() == tok::comma) {
// ArgTokens - Build up a list of tokens that make up this argument.
std::vector<LexerToken> ArgTokens;
// C99 6.10.3p11: Keep track of the number of l_parens we have seen.
unsigned NumParens = 0;
while (1) {
LexUnexpandedToken(Tok);
if (Tok.getKind() == tok::eof) {
Diag(MacroName, diag::err_unterm_macro_invoc);
// Do not lose the EOF. Return it to the client.
MacroName = Tok;
return 0;
} else if (Tok.getKind() == tok::r_paren) {
// If we found the ) token, the macro arg list is done.
if (NumParens-- == 0)
break;
} else if (Tok.getKind() == tok::l_paren) {
++NumParens;
} else if (Tok.getKind() == tok::comma && NumParens == 0) {
// Comma ends this argument if there are more fixed arguments expected.
if (NumFixedArgsLeft)
break;
// If this is not a variadic macro, too many formals were specified.
if (!isVariadic) {
// Emit the diagnostic at the macro name in case there is a missing ).
// Emitting it at the , could be far away from the macro name.
Diag(MacroName, diag::err_too_many_formals_in_macro_invoc);
return 0;
}
// Otherwise, continue to add the tokens to this variable argument.
}
ArgTokens.push_back(Tok);
}
// Remember the tokens that make up this argument. This destroys ArgTokens.
Args->addArgument(ArgTokens);
--NumFixedArgsLeft;
};
// Okay, we either found the r_paren. Check to see if we parsed too few
// arguments.
unsigned NumFormals = Args->getNumArguments();
unsigned MinArgsExpected = MI->getNumArgs();
// C99 expects us to pass at least one vararg arg (but as an extension, we
// don't require this). GNU-style varargs already include the 'rest' name in
// the count.
MinArgsExpected += MI->isC99Varargs();
if (NumFormals < MinArgsExpected) {
// There are several cases where too few arguments is ok, handle them now.
if (NumFormals+1 == MinArgsExpected && MI->isVariadic()) {
// Varargs where the named vararg parameter is missing: ok as extension.
// #define A(x, ...)
// A("blah")
Diag(Tok, diag::ext_missing_varargs_arg);
} else if (MI->getNumArgs() == 1) {
// #define A(x)
// A()
// is ok. Add an empty argument.
std::vector<LexerToken> ArgTokens;
Args->addArgument(ArgTokens);
} else {
// Otherwise, emit the error.
Diag(Tok, diag::err_too_few_formals_in_macro_invoc);
return 0;
}
}
return Args.release();
}
/// ComputeDATE_TIME - Compute the current time, enter it into the specified
/// scratch buffer, then return DATELoc/TIMELoc locations with the position of
/// the identifier tokens inserted.
static void ComputeDATE_TIME(SourceLocation &DATELoc, SourceLocation &TIMELoc,
ScratchBuffer *ScratchBuf) {
time_t TT = time(0);
struct tm *TM = localtime(&TT);
static const char * const Months[] = {
"Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"
};
char TmpBuffer[100];
sprintf(TmpBuffer, "\"%s %2d %4d\"", Months[TM->tm_mon], TM->tm_mday,
TM->tm_year+1900);
DATELoc = ScratchBuf->getToken(TmpBuffer, strlen(TmpBuffer));
sprintf(TmpBuffer, "\"%02d:%02d:%02d\"", TM->tm_hour, TM->tm_min, TM->tm_sec);
TIMELoc = ScratchBuf->getToken(TmpBuffer, strlen(TmpBuffer));
}
/// ExpandBuiltinMacro - If an identifier token is read that is to be expanded
/// as a builtin macro, handle it and return the next token as 'Tok'.
void Preprocessor::ExpandBuiltinMacro(LexerToken &Tok) {
// Figure out which token this is.
IdentifierInfo *II = Tok.getIdentifierInfo();
assert(II && "Can't be a macro without id info!");
// If this is an _Pragma directive, expand it, invoke the pragma handler, then
// lex the token after it.
if (II == Ident_Pragma)
return Handle_Pragma(Tok);
++NumBuiltinMacroExpanded;
char TmpBuffer[100];
// Set up the return result.
Tok.SetIdentifierInfo(0);
Tok.ClearFlag(LexerToken::NeedsCleaning);
if (II == Ident__LINE__) {
// __LINE__ expands to a simple numeric value.
sprintf(TmpBuffer, "%u", SourceMgr.getLineNumber(Tok.getLocation()));
unsigned Length = strlen(TmpBuffer);
Tok.SetKind(tok::numeric_constant);
Tok.SetLength(Length);
Tok.SetLocation(ScratchBuf->getToken(TmpBuffer, Length, Tok.getLocation()));
} else if (II == Ident__FILE__ || II == Ident__BASE_FILE__) {
SourceLocation Loc = Tok.getLocation();
if (II == Ident__BASE_FILE__) {
Diag(Tok, diag::ext_pp_base_file);
SourceLocation NextLoc = SourceMgr.getIncludeLoc(Loc.getFileID());
while (NextLoc.getFileID() != 0) {
Loc = NextLoc;
NextLoc = SourceMgr.getIncludeLoc(Loc.getFileID());
}
}
// Escape this filename. Turn '\' -> '\\' '"' -> '\"'
std::string FN = SourceMgr.getSourceName(Loc);
FN = Lexer::Stringify(FN);
Tok.SetKind(tok::string_literal);
Tok.SetLength(FN.size());
Tok.SetLocation(ScratchBuf->getToken(&FN[0], FN.size(), Tok.getLocation()));
} else if (II == Ident__DATE__) {
if (!DATELoc.isValid())
ComputeDATE_TIME(DATELoc, TIMELoc, ScratchBuf);
Tok.SetKind(tok::string_literal);
Tok.SetLength(strlen("\"Mmm dd yyyy\""));
Tok.SetLocation(SourceMgr.getInstantiationLoc(DATELoc, Tok.getLocation()));
} else if (II == Ident__TIME__) {
if (!TIMELoc.isValid())
ComputeDATE_TIME(DATELoc, TIMELoc, ScratchBuf);
Tok.SetKind(tok::string_literal);
Tok.SetLength(strlen("\"hh:mm:ss\""));
Tok.SetLocation(SourceMgr.getInstantiationLoc(TIMELoc, Tok.getLocation()));
} else if (II == Ident__INCLUDE_LEVEL__) {
Diag(Tok, diag::ext_pp_include_level);
// Compute the include depth of this token.
unsigned Depth = 0;
SourceLocation Loc = SourceMgr.getIncludeLoc(Tok.getLocation().getFileID());
for (; Loc.getFileID() != 0; ++Depth)
Loc = SourceMgr.getIncludeLoc(Loc.getFileID());
// __INCLUDE_LEVEL__ expands to a simple numeric value.
sprintf(TmpBuffer, "%u", Depth);
unsigned Length = strlen(TmpBuffer);
Tok.SetKind(tok::numeric_constant);
Tok.SetLength(Length);
Tok.SetLocation(ScratchBuf->getToken(TmpBuffer, Length, Tok.getLocation()));
} else if (II == Ident__TIMESTAMP__) {
// MSVC, ICC, GCC, VisualAge C++ extension. The generated string should be
// of the form "Ddd Mmm dd hh::mm::ss yyyy", which is returned by asctime.
Diag(Tok, diag::ext_pp_timestamp);
// Get the file that we are lexing out of. If we're currently lexing from
// a macro, dig into the include stack.
const FileEntry *CurFile = 0;
Lexer *TheLexer = getCurrentFileLexer();
if (TheLexer)
CurFile = SourceMgr.getFileEntryForFileID(TheLexer->getCurFileID());
// If this file is older than the file it depends on, emit a diagnostic.
const char *Result;
if (CurFile) {
time_t TT = CurFile->getModificationTime();
struct tm *TM = localtime(&TT);
Result = asctime(TM);
} else {
Result = "??? ??? ?? ??:??:?? ????\n";
}
TmpBuffer[0] = '"';
strcpy(TmpBuffer+1, Result);
unsigned Len = strlen(TmpBuffer);
TmpBuffer[Len-1] = '"'; // Replace the newline with a quote.
Tok.SetKind(tok::string_literal);
Tok.SetLength(Len);
Tok.SetLocation(ScratchBuf->getToken(TmpBuffer, Len, Tok.getLocation()));
} else {
assert(0 && "Unknown identifier!");
}
}
namespace {
struct UnusedIdentifierReporter : public IdentifierVisitor {
Preprocessor &PP;
UnusedIdentifierReporter(Preprocessor &pp) : PP(pp) {}
void VisitIdentifier(IdentifierInfo &II) const {
if (II.getMacroInfo() && !II.getMacroInfo()->isUsed())
PP.Diag(II.getMacroInfo()->getDefinitionLoc(), diag::pp_macro_not_used);
}
};
}
//===----------------------------------------------------------------------===//
// 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(LexerToken &Identifier,
const char *BufPtr) {
assert(Identifier.getKind() == 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(BufPtr, BufPtr+Identifier.getLength());
} else {
// Cleaning needed, alloca a buffer, clean into it, then use the buffer.
const char *TmpBuf = (char*)alloca(Identifier.getLength());
unsigned Size = getSpelling(Identifier, TmpBuf);
II = getIdentifierInfo(TmpBuf, TmpBuf+Size);
}
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').
void Preprocessor::HandleIdentifier(LexerToken &Identifier) {
if (Identifier.getIdentifierInfo() == 0) {
// If we are skipping tokens (because we are in a #if 0 block), there will
// be no identifier info, just return the token.
assert(isSkipping() && "Token isn't an identifier?");
return;
}
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() && CurLexer) {
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 = II.getMacroInfo())
if (MI->isEnabled() && !DisableMacroExpansion)
if (!HandleMacroExpandedIdentifier(Identifier, MI))
return;
// Change the kind of this identifier to the appropriate token kind, e.g.
// turning "for" into a keyword.
Identifier.SetKind(II.getTokenID());
// If this is an extension token, diagnose its use.
if (II.isExtensionToken()) Diag(Identifier, diag::ext_token_used);
}
/// HandleEndOfFile - This callback is invoked when the lexer hits the end of
/// the current file. This either returns the EOF token or pops a level off
/// the include stack and keeps going.
void Preprocessor::HandleEndOfFile(LexerToken &Result, bool isEndOfMacro) {
assert(!CurMacroExpander &&
"Ending a file when currently in a macro!");
// If we are in a #if 0 block skipping tokens, and we see the end of the file,
// this is an error condition. Just return the EOF token up to
// SkipExcludedConditionalBlock. The Lexer will have already have issued
// errors for the unterminated #if's on the conditional stack.
if (isSkipping()) {
Result.StartToken();
CurLexer->BufferPtr = CurLexer->BufferEnd;
CurLexer->FormTokenWithChars(Result, CurLexer->BufferEnd);
Result.SetKind(tok::eof);
return;
}
// See if this file had a controlling macro.
if (CurLexer) { // Not ending a macro, ignore it.
if (const IdentifierInfo *ControllingMacro =
CurLexer->MIOpt.GetControllingMacroAtEndOfFile()) {
// Okay, this has a controlling macro, remember in PerFileInfo.
if (const FileEntry *FE =
SourceMgr.getFileEntryForFileID(CurLexer->getCurFileID()))
getFileInfo(FE).ControllingMacro = ControllingMacro;
}
}
// If this is a #include'd file, pop it off the include stack and continue
// lexing the #includer file.
if (!IncludeMacroStack.empty()) {
// We're done with the #included file.
delete CurLexer;
CurLexer = IncludeMacroStack.back().TheLexer;
CurDirLookup = IncludeMacroStack.back().TheDirLookup;
CurMacroExpander = IncludeMacroStack.back().TheMacroExpander;
IncludeMacroStack.pop_back();
// Notify the client, if desired, that we are in a new source file.
if (FileChangeHandler && !isEndOfMacro && CurLexer) {
DirectoryLookup::DirType FileType = DirectoryLookup::NormalHeaderDir;
// Get the file entry for the current file.
if (const FileEntry *FE =
SourceMgr.getFileEntryForFileID(CurLexer->getCurFileID()))
FileType = getFileInfo(FE).DirInfo;
FileChangeHandler(CurLexer->getSourceLocation(CurLexer->BufferPtr),
ExitFile, FileType);
}
return Lex(Result);
}
Result.StartToken();
CurLexer->BufferPtr = CurLexer->BufferEnd;
CurLexer->FormTokenWithChars(Result, CurLexer->BufferEnd);
Result.SetKind(tok::eof);
// We're done with the #included file.
delete CurLexer;
CurLexer = 0;
// This is the end of the top-level file.
Identifiers.VisitIdentifiers(UnusedIdentifierReporter(*this));
}
/// HandleEndOfMacro - This callback is invoked when the lexer hits the end of
/// the current macro line.
void Preprocessor::HandleEndOfMacro(LexerToken &Result) {
assert(CurMacroExpander && !CurLexer &&
"Ending a macro when currently in a #include file!");
// Mark macro not ignored now that it is no longer being expanded.
CurMacroExpander->getMacro().EnableMacro();
delete CurMacroExpander;
// Handle this like a #include file being popped off the stack.
CurMacroExpander = 0;
return HandleEndOfFile(Result, true);
}
//===----------------------------------------------------------------------===//
// Utility Methods for Preprocessor Directive Handling.
//===----------------------------------------------------------------------===//
/// DiscardUntilEndOfDirective - Read and discard all tokens remaining on the
/// current line until the tok::eom token is found.
void Preprocessor::DiscardUntilEndOfDirective() {
LexerToken Tmp;
do {
LexUnexpandedToken(Tmp);
} while (Tmp.getKind() != tok::eom);
}
/// ReadMacroName - Lex and validate a macro name, which occurs after a
/// #define or #undef. This sets the token kind to eom and discards the rest
/// of the macro line if the macro name is invalid. isDefineUndef is 1 if
/// this is due to a a #define, 2 if #undef directive, 0 if it is something
/// else (e.g. #ifdef).
void Preprocessor::ReadMacroName(LexerToken &MacroNameTok, char isDefineUndef) {
// Read the token, don't allow macro expansion on it.
LexUnexpandedToken(MacroNameTok);
// Missing macro name?
if (MacroNameTok.getKind() == tok::eom)
return Diag(MacroNameTok, diag::err_pp_missing_macro_name);
IdentifierInfo *II = MacroNameTok.getIdentifierInfo();
if (II == 0) {
Diag(MacroNameTok, diag::err_pp_macro_not_identifier);
// Fall through on error.
} else if (0) {
// FIXME: C++. Error if defining a C++ named operator.
} else if (isDefineUndef && II->getName()[0] == 'd' && // defined
!strcmp(II->getName()+1, "efined")) {
// Error if defining "defined": C99 6.10.8.4.
Diag(MacroNameTok, diag::err_defined_macro_name);
} else if (isDefineUndef && II->getMacroInfo() &&
II->getMacroInfo()->isBuiltinMacro()) {
// Error if defining "__LINE__" and other builtins: C99 6.10.8.4.
if (isDefineUndef == 1)
Diag(MacroNameTok, diag::pp_redef_builtin_macro);
else
Diag(MacroNameTok, diag::pp_undef_builtin_macro);
} else {
// Okay, we got a good identifier node. Return it.
return;
}
// Invalid macro name, read and discard the rest of the line. Then set the
// token kind to tok::eom.
MacroNameTok.SetKind(tok::eom);
return DiscardUntilEndOfDirective();
}
/// CheckEndOfDirective - Ensure that the next token is a tok::eom token. If
/// not, emit a diagnostic and consume up until the eom.
void Preprocessor::CheckEndOfDirective(const char *DirType) {
LexerToken Tmp;
Lex(Tmp);
// There should be no tokens after the directive, but we allow them as an
// extension.
if (Tmp.getKind() != tok::eom) {
Diag(Tmp, diag::ext_pp_extra_tokens_at_eol, DirType);
DiscardUntilEndOfDirective();
}
}
/// SkipExcludedConditionalBlock - We just read a #if or related directive and
/// decided that the subsequent tokens are in the #if'd out portion of the
/// file. Lex the rest of the file, until we see an #endif. If
/// FoundNonSkipPortion is true, then we have already emitted code for part of
/// this #if directive, so #else/#elif blocks should never be entered. If ElseOk
/// is true, then #else directives are ok, if not, then we have already seen one
/// so a #else directive is a duplicate. When this returns, the caller can lex
/// the first valid token.
void Preprocessor::SkipExcludedConditionalBlock(SourceLocation IfTokenLoc,
bool FoundNonSkipPortion,
bool FoundElse) {
++NumSkipped;
assert(CurMacroExpander == 0 && CurLexer &&
"Lexing a macro, not a file?");
CurLexer->pushConditionalLevel(IfTokenLoc, /*isSkipping*/false,
FoundNonSkipPortion, FoundElse);
// Know that we are going to be skipping tokens. Set this flag to indicate
// this, which has a couple of effects:
// 1. If EOF of the current lexer is found, the include stack isn't popped.
// 2. Identifier information is not looked up for identifier tokens. As an
// effect of this, implicit macro expansion is naturally disabled.
// 3. "#" tokens at the start of a line are treated as normal tokens, not
// implicitly transformed by the lexer.
// 4. All notes, warnings, and extension messages are disabled.
//
SkippingContents = true;
LexerToken Tok;
while (1) {
CurLexer->Lex(Tok);
// If this is the end of the buffer, we have an error. The lexer will have
// already handled this error condition, so just return and let the caller
// lex after this #include.
if (Tok.getKind() == tok::eof) break;
// If this token is not a preprocessor directive, just skip it.
if (Tok.getKind() != tok::hash || !Tok.isAtStartOfLine())
continue;
// We just parsed a # character at the start of a line, so we're in
// directive mode. Tell the lexer this so any newlines we see will be
// converted into an EOM token (this terminates the macro).
CurLexer->ParsingPreprocessorDirective = true;
// Read the next token, the directive flavor.
LexUnexpandedToken(Tok);
// If this isn't an identifier directive (e.g. is "# 1\n" or "#\n", or
// something bogus), skip it.
if (Tok.getKind() != tok::identifier) {
CurLexer->ParsingPreprocessorDirective = false;
continue;
}
// If the first letter isn't i or e, it isn't intesting to us. We know that
// this is safe in the face of spelling differences, because there is no way
// to spell an i/e in a strange way that is another letter. Skipping this
// allows us to avoid looking up the identifier info for #define/#undef and
// other common directives.
const char *RawCharData = SourceMgr.getCharacterData(Tok.getLocation());
char FirstChar = RawCharData[0];
if (FirstChar >= 'a' && FirstChar <= 'z' &&
FirstChar != 'i' && FirstChar != 'e') {
CurLexer->ParsingPreprocessorDirective = false;
continue;
}
// Get the identifier name without trigraphs or embedded newlines. Note
// that we can't use Tok.getIdentifierInfo() because its lookup is disabled
// when skipping.
// TODO: could do this with zero copies in the no-clean case by using
// strncmp below.
char Directive[20];
unsigned IdLen;
if (!Tok.needsCleaning() && Tok.getLength() < 20) {
IdLen = Tok.getLength();
memcpy(Directive, RawCharData, IdLen);
Directive[IdLen] = 0;
} else {
std::string DirectiveStr = getSpelling(Tok);
IdLen = DirectiveStr.size();
if (IdLen >= 20) {
CurLexer->ParsingPreprocessorDirective = false;
continue;
}
memcpy(Directive, &DirectiveStr[0], IdLen);
Directive[IdLen] = 0;
}
if (FirstChar == 'i' && Directive[1] == 'f') {
if ((IdLen == 2) || // "if"
(IdLen == 5 && !strcmp(Directive+2, "def")) || // "ifdef"
(IdLen == 6 && !strcmp(Directive+2, "ndef"))) { // "ifndef"
// We know the entire #if/#ifdef/#ifndef block will be skipped, don't
// bother parsing the condition.
DiscardUntilEndOfDirective();
CurLexer->pushConditionalLevel(Tok.getLocation(), /*wasskipping*/true,
/*foundnonskip*/false,
/*fnddelse*/false);
}
} else if (FirstChar == 'e') {
if (IdLen == 5 && !strcmp(Directive+1, "ndif")) { // "endif"
CheckEndOfDirective("#endif");
PPConditionalInfo CondInfo;
CondInfo.WasSkipping = true; // Silence bogus warning.
bool InCond = CurLexer->popConditionalLevel(CondInfo);
assert(!InCond && "Can't be skipping if not in a conditional!");
// If we popped the outermost skipping block, we're done skipping!
if (!CondInfo.WasSkipping)
break;
} else if (IdLen == 4 && !strcmp(Directive+1, "lse")) { // "else".
// #else directive in a skipping conditional. If not in some other
// skipping conditional, and if #else hasn't already been seen, enter it
// as a non-skipping conditional.
CheckEndOfDirective("#else");
PPConditionalInfo &CondInfo = CurLexer->peekConditionalLevel();
// If this is a #else with a #else before it, report the error.
if (CondInfo.FoundElse) Diag(Tok, diag::pp_err_else_after_else);
// Note that we've seen a #else in this conditional.
CondInfo.FoundElse = true;
// If the conditional is at the top level, and the #if block wasn't
// entered, enter the #else block now.
if (!CondInfo.WasSkipping && !CondInfo.FoundNonSkip) {
CondInfo.FoundNonSkip = true;
break;
}
} else if (IdLen == 4 && !strcmp(Directive+1, "lif")) { // "elif".
PPConditionalInfo &CondInfo = CurLexer->peekConditionalLevel();
bool ShouldEnter;
// If this is in a skipping block or if we're already handled this #if
// block, don't bother parsing the condition.
if (CondInfo.WasSkipping || CondInfo.FoundNonSkip) {
DiscardUntilEndOfDirective();
ShouldEnter = false;
} else {
// Restore the value of SkippingContents so that identifiers are
// looked up, etc, inside the #elif expression.
assert(SkippingContents && "We have to be skipping here!");
SkippingContents = false;
IdentifierInfo *IfNDefMacro = 0;
ShouldEnter = EvaluateDirectiveExpression(IfNDefMacro);
SkippingContents = true;
}
// If this is a #elif with a #else before it, report the error.
if (CondInfo.FoundElse) Diag(Tok, diag::pp_err_elif_after_else);
// If this condition is true, enter it!
if (ShouldEnter) {
CondInfo.FoundNonSkip = true;
break;
}
}
}
CurLexer->ParsingPreprocessorDirective = false;
}
// Finally, if we are out of the conditional (saw an #endif or ran off the end
// of the file, just stop skipping and return to lexing whatever came after
// the #if block.
SkippingContents = false;
}
//===----------------------------------------------------------------------===//
// Preprocessor Directive Handling.
//===----------------------------------------------------------------------===//
/// HandleDirective - This callback is invoked when the lexer sees a # token
/// at the start of a line. This consumes the directive, modifies the
/// lexer/preprocessor state, and advances the lexer(s) so that the next token
/// read is the correct one.
void Preprocessor::HandleDirective(LexerToken &Result) {
// FIXME: Traditional: # with whitespace before it not recognized by K&R?
// We just parsed a # character at the start of a line, so we're in directive
// mode. Tell the lexer this so any newlines we see will be converted into an
// EOM token (which terminates the directive).
CurLexer->ParsingPreprocessorDirective = true;
++NumDirectives;
// We are about to read a token. For the multiple-include optimization FA to
// work, we have to remember if we had read any tokens *before* this
// pp-directive.
bool ReadAnyTokensBeforeDirective = CurLexer->MIOpt.getHasReadAnyTokensVal();
// Read the next token, the directive flavor. This isn't expanded due to
// C99 6.10.3p8.
LexUnexpandedToken(Result);
// C99 6.10.3p11: Is this preprocessor directive in macro invocation? e.g.:
// #define A(x) #x
// A(abc
// #warning blah
// def)
// If so, the user is relying on non-portable behavior, emit a diagnostic.
if (InMacroFormalArgs)
Diag(Result, diag::ext_embedded_directive);
switch (Result.getKind()) {
default: break;
case tok::eom:
return; // null directive.
#if 0
case tok::numeric_constant:
// FIXME: implement # 7 line numbers!
break;
#endif
case tok::kw_else:
return HandleElseDirective(Result);
case tok::kw_if:
return HandleIfDirective(Result, ReadAnyTokensBeforeDirective);
case tok::identifier:
// Get the identifier name without trigraphs or embedded newlines.
const char *Directive = Result.getIdentifierInfo()->getName();
bool isExtension = false;
switch (Result.getIdentifierInfo()->getNameLength()) {
case 4:
if (Directive[0] == 'l' && !strcmp(Directive, "line"))
; // FIXME: implement #line
if (Directive[0] == 'e' && !strcmp(Directive, "elif"))
return HandleElifDirective(Result);
if (Directive[0] == 's' && !strcmp(Directive, "sccs"))
return HandleIdentSCCSDirective(Result);
break;
case 5:
if (Directive[0] == 'e' && !strcmp(Directive, "endif"))
return HandleEndifDirective(Result);
if (Directive[0] == 'i' && !strcmp(Directive, "ifdef"))
return HandleIfdefDirective(Result, false, true/*not valid for miopt*/);
if (Directive[0] == 'u' && !strcmp(Directive, "undef"))
return HandleUndefDirective(Result);
if (Directive[0] == 'e' && !strcmp(Directive, "error"))
return HandleUserDiagnosticDirective(Result, false);
if (Directive[0] == 'i' && !strcmp(Directive, "ident"))
return HandleIdentSCCSDirective(Result);
break;
case 6:
if (Directive[0] == 'd' && !strcmp(Directive, "define"))
return HandleDefineDirective(Result);
if (Directive[0] == 'i' && !strcmp(Directive, "ifndef"))
return HandleIfdefDirective(Result, true, ReadAnyTokensBeforeDirective);
if (Directive[0] == 'i' && !strcmp(Directive, "import"))
return HandleImportDirective(Result);
if (Directive[0] == 'p' && !strcmp(Directive, "pragma"))
return HandlePragmaDirective();
if (Directive[0] == 'a' && !strcmp(Directive, "assert"))
isExtension = true; // FIXME: implement #assert
break;
case 7:
if (Directive[0] == 'i' && !strcmp(Directive, "include"))
return HandleIncludeDirective(Result); // Handle #include.
if (Directive[0] == 'w' && !strcmp(Directive, "warning")) {
Diag(Result, diag::ext_pp_warning_directive);
return HandleUserDiagnosticDirective(Result, true);
}
break;
case 8:
if (Directive[0] == 'u' && !strcmp(Directive, "unassert")) {
isExtension = true; // FIXME: implement #unassert
}
break;
case 12:
if (Directive[0] == 'i' && !strcmp(Directive, "include_next"))
return HandleIncludeNextDirective(Result); // Handle #include_next.
break;
}
break;
}
// If we reached here, the preprocessing token is not valid!
Diag(Result, diag::err_pp_invalid_directive);
// Read the rest of the PP line.
DiscardUntilEndOfDirective();
// Okay, we're done parsing the directive.
}
void Preprocessor::HandleUserDiagnosticDirective(LexerToken &Tok,
bool isWarning) {
// Read the rest of the line raw. We do this because we don't want macros
// to be expanded and we don't require that the tokens be valid preprocessing
// tokens. For example, this is allowed: "#warning ` 'foo". GCC does
// collapse multiple consequtive white space between tokens, but this isn't
// specified by the standard.
std::string Message = CurLexer->ReadToEndOfLine();
unsigned DiagID = isWarning ? diag::pp_hash_warning : diag::err_pp_hash_error;
return Diag(Tok, DiagID, Message);
}
/// HandleIdentSCCSDirective - Handle a #ident/#sccs directive.
///
void Preprocessor::HandleIdentSCCSDirective(LexerToken &Tok) {
// Yes, this directive is an extension.
Diag(Tok, diag::ext_pp_ident_directive);
// Read the string argument.
LexerToken StrTok;
Lex(StrTok);
// If the token kind isn't a string, it's a malformed directive.
if (StrTok.getKind() != tok::string_literal)
return Diag(StrTok, diag::err_pp_malformed_ident);
// Verify that there is nothing after the string, other than EOM.
CheckEndOfDirective("#ident");
if (IdentHandler)
IdentHandler(Tok.getLocation(), getSpelling(StrTok));
}
//===----------------------------------------------------------------------===//
// Preprocessor Include Directive Handling.
//===----------------------------------------------------------------------===//
/// HandleIncludeDirective - The "#include" tokens have just been read, read the
/// file to be included from the lexer, then include it! This is a common
/// routine with functionality shared between #include, #include_next and
/// #import.
void Preprocessor::HandleIncludeDirective(LexerToken &IncludeTok,
const DirectoryLookup *LookupFrom,
bool isImport) {
++NumIncluded;
LexerToken FilenameTok;
std::string Filename = CurLexer->LexIncludeFilename(FilenameTok);
// If the token kind is EOM, the error has already been diagnosed.
if (FilenameTok.getKind() == tok::eom)
return;
// Verify that there is nothing after the filename, other than EOM. Use the
// preprocessor to lex this in case lexing the filename entered a macro.
CheckEndOfDirective("#include");
// Check that we don't have infinite #include recursion.
if (IncludeMacroStack.size() == MaxAllowedIncludeStackDepth-1)
return Diag(FilenameTok, diag::err_pp_include_too_deep);
// Find out whether the filename is <x> or "x".
bool isAngled = Filename[0] == '<';
// Remove the quotes.
Filename = std::string(Filename.begin()+1, Filename.end()-1);
// Search include directories.
const DirectoryLookup *CurDir;
const FileEntry *File = LookupFile(Filename, isAngled, LookupFrom, CurDir);
if (File == 0)
return Diag(FilenameTok, diag::err_pp_file_not_found);
// Get information about this file.
PerFileInfo &FileInfo = getFileInfo(File);
// If this is a #import directive, check that we have not already imported
// this header.
if (isImport) {
// If this has already been imported, don't import it again.
FileInfo.isImport = true;
// Has this already been #import'ed or #include'd?
if (FileInfo.NumIncludes) return;
} else {
// Otherwise, if this is a #include of a file that was previously #import'd
// or if this is the second #include of a #pragma once file, ignore it.
if (FileInfo.isImport)
return;
}
// Next, check to see if the file is wrapped with #ifndef guards. If so, and
// if the macro that guards it is defined, we know the #include has no effect.
if (FileInfo.ControllingMacro && FileInfo.ControllingMacro->getMacroInfo()) {
++NumMultiIncludeFileOptzn;
return;
}
// Look up the file, create a File ID for it.
unsigned FileID = SourceMgr.createFileID(File, FilenameTok.getLocation());
if (FileID == 0)
return Diag(FilenameTok, diag::err_pp_file_not_found);
// Finally, if all is good, enter the new file!
EnterSourceFile(FileID, CurDir);
// Increment the number of times this file has been included.
++FileInfo.NumIncludes;
}
/// HandleIncludeNextDirective - Implements #include_next.
///
void Preprocessor::HandleIncludeNextDirective(LexerToken &IncludeNextTok) {
Diag(IncludeNextTok, diag::ext_pp_include_next_directive);
// #include_next is like #include, except that we start searching after
// the current found directory. If we can't do this, issue a
// diagnostic.
const DirectoryLookup *Lookup = CurDirLookup;
if (isInPrimaryFile()) {
Lookup = 0;
Diag(IncludeNextTok, diag::pp_include_next_in_primary);
} else if (Lookup == 0) {
Diag(IncludeNextTok, diag::pp_include_next_absolute_path);
} else {
// Start looking up in the next directory.
++Lookup;
}
return HandleIncludeDirective(IncludeNextTok, Lookup);
}
/// HandleImportDirective - Implements #import.
///
void Preprocessor::HandleImportDirective(LexerToken &ImportTok) {
Diag(ImportTok, diag::ext_pp_import_directive);
return HandleIncludeDirective(ImportTok, 0, true);
}
//===----------------------------------------------------------------------===//
// Preprocessor Macro Directive Handling.
//===----------------------------------------------------------------------===//
/// ReadMacroDefinitionArgList - The ( starting an argument list of a macro
/// definition has just been read. Lex the rest of the arguments and the
/// closing ), updating MI with what we learn. Return true if an error occurs
/// parsing the arg list.
bool Preprocessor::ReadMacroDefinitionArgList(MacroInfo *MI) {
LexerToken Tok;
while (1) {
LexUnexpandedToken(Tok);
switch (Tok.getKind()) {
case tok::r_paren:
// Found the end of the argument list.
if (MI->arg_begin() == MI->arg_end()) return false; // #define FOO()
// Otherwise we have #define FOO(A,)
Diag(Tok, diag::err_pp_expected_ident_in_arg_list);
return true;
case tok::ellipsis: // #define X(... -> C99 varargs
// Warn if use of C99 feature in non-C99 mode.
if (!Features.C99) Diag(Tok, diag::ext_variadic_macro);
// Lex the token after the identifier.
LexUnexpandedToken(Tok);
if (Tok.getKind() != tok::r_paren) {
Diag(Tok, diag::err_pp_missing_rparen_in_macro_def);
return true;
}
MI->setIsC99Varargs();
return false;
case tok::eom: // #define X(
Diag(Tok, diag::err_pp_missing_rparen_in_macro_def);
return true;
default: // #define X(1
Diag(Tok, diag::err_pp_invalid_tok_in_arg_list);
return true;
case tok::identifier:
IdentifierInfo *II = Tok.getIdentifierInfo();
// If this is already used as an argument, it is used multiple times (e.g.
// #define X(A,A.
if (II->isMacroArg()) { // C99 6.10.3p6
Diag(Tok, diag::err_pp_duplicate_name_in_arg_list, II->getName());
return true;
}
// Add the argument to the macro info.
MI->addArgument(II);
// Remember it is an argument now.
II->setIsMacroArg(true);
// Lex the token after the identifier.
LexUnexpandedToken(Tok);
switch (Tok.getKind()) {
default: // #define X(A B
Diag(Tok, diag::err_pp_expected_comma_in_arg_list);
return true;
case tok::r_paren: // #define X(A)
return false;
case tok::comma: // #define X(A,
break;
case tok::ellipsis: // #define X(A... -> GCC extension
// Diagnose extension.
Diag(Tok, diag::ext_named_variadic_macro);
// Lex the token after the identifier.
LexUnexpandedToken(Tok);
if (Tok.getKind() != tok::r_paren) {
Diag(Tok, diag::err_pp_missing_rparen_in_macro_def);
return true;
}
MI->setIsGNUVarargs();
return false;
}
}
}
}
/// HandleDefineDirective - Implements #define. This consumes the entire macro
/// line then lets the caller lex the next real token.
///
void Preprocessor::HandleDefineDirective(LexerToken &DefineTok) {
++NumDefined;
LexerToken MacroNameTok;
ReadMacroName(MacroNameTok, 1);
// Error reading macro name? If so, diagnostic already issued.
if (MacroNameTok.getKind() == tok::eom)
return;
MacroInfo *MI = new MacroInfo(MacroNameTok.getLocation());
LexerToken Tok;
LexUnexpandedToken(Tok);
// FIXME: Enable __VA_ARGS__.
// If this is a function-like macro definition, parse the argument list,
// marking each of the identifiers as being used as macro arguments. Also,
// check other constraints on the first token of the macro body.
if (Tok.getKind() == tok::eom) {
// If there is no body to this macro, we have no special handling here.
} else if (Tok.getKind() == tok::l_paren && !Tok.hasLeadingSpace()) {
// This is a function-like macro definition. Read the argument list.
MI->setIsFunctionLike();
if (ReadMacroDefinitionArgList(MI)) {
// Clear the "isMacroArg" flags from all the macro arguments parsed.
MI->SetIdentifierIsMacroArgFlags(false);
// Forget about MI.
delete MI;
// Throw away the rest of the line.
if (CurLexer->ParsingPreprocessorDirective)
DiscardUntilEndOfDirective();
return;
}
// Read the first token after the arg list for down below.
LexUnexpandedToken(Tok);
} else if (!Tok.hasLeadingSpace()) {
// C99 requires whitespace between the macro definition and the body. Emit
// a diagnostic for something like "#define X+".
if (Features.C99) {
Diag(Tok, diag::ext_c99_whitespace_required_after_macro_name);
} else {
// FIXME: C90/C++ do not get this diagnostic, but it does get a similar
// one in some cases!
}
} else {
// This is a normal token with leading space. Clear the leading space
// marker on the first token to get proper expansion.
Tok.ClearFlag(LexerToken::LeadingSpace);
}
// Read the rest of the macro body.
while (Tok.getKind() != tok::eom) {
MI->AddTokenToBody(Tok);
// Check C99 6.10.3.2p1: ensure that # operators are followed by macro
// parameters.
if (Tok.getKind() != tok::hash) {
// Get the next token of the macro.
LexUnexpandedToken(Tok);
continue;
}
// Get the next token of the macro.
LexUnexpandedToken(Tok);
// Not a macro arg identifier?
if (!Tok.getIdentifierInfo() || !Tok.getIdentifierInfo()->isMacroArg()) {
Diag(Tok, diag::err_pp_stringize_not_parameter);
// Clear the "isMacroArg" flags from all the macro arguments.
MI->SetIdentifierIsMacroArgFlags(false);
delete MI;
return;
}
// Things look ok, add the param name token to the macro.
MI->AddTokenToBody(Tok);
// Get the next token of the macro.
LexUnexpandedToken(Tok);
}
// Clear the "isMacroArg" flags from all the macro arguments.
MI->SetIdentifierIsMacroArgFlags(false);
// Check that there is no paste (##) operator at the begining or end of the
// replacement list.
unsigned NumTokens = MI->getNumTokens();
if (NumTokens != 0) {
if (MI->getReplacementToken(0).getKind() == tok::hashhash) {
Diag(MI->getReplacementToken(0), diag::err_paste_at_start);
delete MI;
return;
}
if (MI->getReplacementToken(NumTokens-1).getKind() == tok::hashhash) {
Diag(MI->getReplacementToken(NumTokens-1), diag::err_paste_at_end);
delete MI;
return;
}
}
// If this is the primary source file, remember that this macro hasn't been
// used yet.
if (isInPrimaryFile())
MI->setIsUsed(false);
// Finally, if this identifier already had a macro defined for it, verify that
// the macro bodies are identical and free the old definition.
if (MacroInfo *OtherMI = MacroNameTok.getIdentifierInfo()->getMacroInfo()) {
if (!OtherMI->isUsed())
Diag(OtherMI->getDefinitionLoc(), diag::pp_macro_not_used);
// Macros must be identical. This means all tokes and whitespace separation
// must be the same. C99 6.10.3.2.
if (!MI->isIdenticalTo(*OtherMI, *this)) {
Diag(MI->getDefinitionLoc(), diag::ext_pp_macro_redef,
MacroNameTok.getIdentifierInfo()->getName());
Diag(OtherMI->getDefinitionLoc(), diag::ext_pp_macro_redef2);
}
delete OtherMI;
}
MacroNameTok.getIdentifierInfo()->setMacroInfo(MI);
}
/// HandleUndefDirective - Implements #undef.
///
void Preprocessor::HandleUndefDirective(LexerToken &UndefTok) {
++NumUndefined;
LexerToken MacroNameTok;
ReadMacroName(MacroNameTok, 2);
// Error reading macro name? If so, diagnostic already issued.
if (MacroNameTok.getKind() == tok::eom)
return;
// Check to see if this is the last token on the #undef line.
CheckEndOfDirective("#undef");
// Okay, we finally have a valid identifier to undef.
MacroInfo *MI = MacroNameTok.getIdentifierInfo()->getMacroInfo();
// If the macro is not defined, this is a noop undef, just return.
if (MI == 0) return;
if (!MI->isUsed())
Diag(MI->getDefinitionLoc(), diag::pp_macro_not_used);
// Free macro definition.
delete MI;
MacroNameTok.getIdentifierInfo()->setMacroInfo(0);
}
//===----------------------------------------------------------------------===//
// Preprocessor Conditional Directive Handling.
//===----------------------------------------------------------------------===//
/// HandleIfdefDirective - Implements the #ifdef/#ifndef directive. isIfndef is
/// true when this is a #ifndef directive. ReadAnyTokensBeforeDirective is true
/// if any tokens have been returned or pp-directives activated before this
/// #ifndef has been lexed.
///
void Preprocessor::HandleIfdefDirective(LexerToken &Result, bool isIfndef,
bool ReadAnyTokensBeforeDirective) {
++NumIf;
LexerToken DirectiveTok = Result;
LexerToken MacroNameTok;
ReadMacroName(MacroNameTok);
// Error reading macro name? If so, diagnostic already issued.
if (MacroNameTok.getKind() == tok::eom)
return;
// Check to see if this is the last token on the #if[n]def line.
CheckEndOfDirective(isIfndef ? "#ifndef" : "#ifdef");
// If the start of a top-level #ifdef, inform MIOpt.
if (!ReadAnyTokensBeforeDirective &&
CurLexer->getConditionalStackDepth() == 0) {
assert(isIfndef && "#ifdef shouldn't reach here");
CurLexer->MIOpt.EnterTopLevelIFNDEF(MacroNameTok.getIdentifierInfo());
}
MacroInfo *MI = MacroNameTok.getIdentifierInfo()->getMacroInfo();
// If there is a macro, mark it used.
if (MI) MI->setIsUsed(true);
// Should we include the stuff contained by this directive?
if (!MI == isIfndef) {
// Yes, remember that we are inside a conditional, then lex the next token.
CurLexer->pushConditionalLevel(DirectiveTok.getLocation(), /*wasskip*/false,
/*foundnonskip*/true, /*foundelse*/false);
} else {
// No, skip the contents of this block and return the first token after it.
SkipExcludedConditionalBlock(DirectiveTok.getLocation(),
/*Foundnonskip*/false,
/*FoundElse*/false);
}
}
/// HandleIfDirective - Implements the #if directive.
///
void Preprocessor::HandleIfDirective(LexerToken &IfToken,
bool ReadAnyTokensBeforeDirective) {
++NumIf;
// Parse and evaluation the conditional expression.
IdentifierInfo *IfNDefMacro = 0;
bool ConditionalTrue = EvaluateDirectiveExpression(IfNDefMacro);
// Should we include the stuff contained by this directive?
if (ConditionalTrue) {
// If this condition is equivalent to #ifndef X, and if this is the first
// directive seen, handle it for the multiple-include optimization.
if (!ReadAnyTokensBeforeDirective &&
CurLexer->getConditionalStackDepth() == 0 && IfNDefMacro)
CurLexer->MIOpt.EnterTopLevelIFNDEF(IfNDefMacro);
// Yes, remember that we are inside a conditional, then lex the next token.
CurLexer->pushConditionalLevel(IfToken.getLocation(), /*wasskip*/false,
/*foundnonskip*/true, /*foundelse*/false);
} else {
// No, skip the contents of this block and return the first token after it.
SkipExcludedConditionalBlock(IfToken.getLocation(), /*Foundnonskip*/false,
/*FoundElse*/false);
}
}
/// HandleEndifDirective - Implements the #endif directive.
///
void Preprocessor::HandleEndifDirective(LexerToken &EndifToken) {
++NumEndif;
// Check that this is the whole directive.
CheckEndOfDirective("#endif");
PPConditionalInfo CondInfo;
if (CurLexer->popConditionalLevel(CondInfo)) {
// No conditionals on the stack: this is an #endif without an #if.
return Diag(EndifToken, diag::err_pp_endif_without_if);
}
// If this the end of a top-level #endif, inform MIOpt.
if (CurLexer->getConditionalStackDepth() == 0)
CurLexer->MIOpt.ExitTopLevelConditional();
assert(!CondInfo.WasSkipping && !isSkipping() &&
"This code should only be reachable in the non-skipping case!");
}
void Preprocessor::HandleElseDirective(LexerToken &Result) {
++NumElse;
// #else directive in a non-skipping conditional... start skipping.
CheckEndOfDirective("#else");
PPConditionalInfo CI;
if (CurLexer->popConditionalLevel(CI))
return Diag(Result, diag::pp_err_else_without_if);
// If this is a top-level #else, inform the MIOpt.
if (CurLexer->getConditionalStackDepth() == 0)
CurLexer->MIOpt.FoundTopLevelElse();
// If this is a #else with a #else before it, report the error.
if (CI.FoundElse) Diag(Result, diag::pp_err_else_after_else);
// Finally, skip the rest of the contents of this block and return the first
// token after it.
return SkipExcludedConditionalBlock(CI.IfLoc, /*Foundnonskip*/true,
/*FoundElse*/true);
}
void Preprocessor::HandleElifDirective(LexerToken &ElifToken) {
++NumElse;
// #elif directive in a non-skipping conditional... start skipping.
// We don't care what the condition is, because we will always skip it (since
// the block immediately before it was included).
DiscardUntilEndOfDirective();
PPConditionalInfo CI;
if (CurLexer->popConditionalLevel(CI))
return Diag(ElifToken, diag::pp_err_elif_without_if);
// If this is a top-level #elif, inform the MIOpt.
if (CurLexer->getConditionalStackDepth() == 0)
CurLexer->MIOpt.FoundTopLevelElse();
// If this is a #elif with a #else before it, report the error.
if (CI.FoundElse) Diag(ElifToken, diag::pp_err_elif_after_else);
// Finally, skip the rest of the contents of this block and return the first
// token after it.
return SkipExcludedConditionalBlock(CI.IfLoc, /*Foundnonskip*/true,
/*FoundElse*/CI.FoundElse);
}