maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity
llvm-project/clang/lib/Lex/PPLexerChange.cpp

575 lines
22 KiB
C++
Raw Blame History

//===--- PPLexerChange.cpp - Handle changing lexers in the preprocessor ---===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements pieces of the Preprocessor interface that manage the
// current lexer stack.
//
//===----------------------------------------------------------------------===//
#include "clang/Lex/Preprocessor.h"
#include "clang/Basic/FileManager.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Lex/HeaderSearch.h"
#include "clang/Lex/LexDiagnostic.h"
#include "clang/Lex/MacroInfo.h"
#include "llvm/ADT/StringSwitch.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/Path.h"
using namespace clang;
PPCallbacks::~PPCallbacks() {}
//===----------------------------------------------------------------------===//
// Miscellaneous Methods.
//===----------------------------------------------------------------------===//
/// isInPrimaryFile - Return true if we're in the top-level file, not in a
/// \#include. This looks through macro expansions and active _Pragma lexers.
bool Preprocessor::isInPrimaryFile() const {
if (IsFileLexer())
return IncludeMacroStack.empty();
// If there are any stacked lexers, we're in a #include.
assert(IsFileLexer(IncludeMacroStack[0]) &&
"Top level include stack isn't our primary lexer?");
for (unsigned i = 1, e = IncludeMacroStack.size(); i != e; ++i)
if (IsFileLexer(IncludeMacroStack[i]))
return false;
return true;
}
/// 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.
PreprocessorLexer *Preprocessor::getCurrentFileLexer() const {
if (IsFileLexer())
return CurPPLexer;
// Look for a stacked lexer.
for (unsigned i = IncludeMacroStack.size(); i != 0; --i) {
const IncludeStackInfo& ISI = IncludeMacroStack[i-1];
if (IsFileLexer(ISI))
return ISI.ThePPLexer;
}
return 0;
}
//===----------------------------------------------------------------------===//
// Methods for Entering and Callbacks for leaving various contexts
//===----------------------------------------------------------------------===//
/// 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::EnterSourceFile(FileID FID, const DirectoryLookup *CurDir,
SourceLocation Loc) {
assert(!CurTokenLexer && "Cannot #include a file inside a macro!");
++NumEnteredSourceFiles;
if (MaxIncludeStackDepth < IncludeMacroStack.size())
MaxIncludeStackDepth = IncludeMacroStack.size();
if (PTH) {
if (PTHLexer *PL = PTH->CreateLexer(FID)) {
EnterSourceFileWithPTH(PL, CurDir);
return;
}
}
// Get the MemoryBuffer for this FID, if it fails, we fail.
bool Invalid = false;
const llvm::MemoryBuffer *InputFile =
getSourceManager().getBuffer(FID, Loc, &Invalid);
if (Invalid) {
SourceLocation FileStart = SourceMgr.getLocForStartOfFile(FID);
Diag(Loc, diag::err_pp_error_opening_file)
<< std::string(SourceMgr.getBufferName(FileStart)) << "";
return;
}
if (isCodeCompletionEnabled() &&
SourceMgr.getFileEntryForID(FID) == CodeCompletionFile) {
CodeCompletionFileLoc = SourceMgr.getLocForStartOfFile(FID);
CodeCompletionLoc =
CodeCompletionFileLoc.getLocWithOffset(CodeCompletionOffset);
}
EnterSourceFileWithLexer(new Lexer(FID, InputFile, *this), CurDir);
return;
}
/// EnterSourceFileWithLexer - 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 (CurPPLexer || CurTokenLexer)
PushIncludeMacroStack();
CurLexer.reset(TheLexer);
CurPPLexer = TheLexer;
CurDirLookup = CurDir;
if (CurLexerKind != CLK_LexAfterModuleImport)
CurLexerKind = CLK_Lexer;
// Notify the client, if desired, that we are in a new source file.
if (Callbacks && !CurLexer->Is_PragmaLexer) {
SrcMgr::CharacteristicKind FileType =
SourceMgr.getFileCharacteristic(CurLexer->getFileLoc());
Callbacks->FileChanged(CurLexer->getFileLoc(),
PPCallbacks::EnterFile, FileType);
}
}
/// EnterSourceFileWithPTH - Add a source file to the top of the include stack
/// and start getting tokens from it using the PTH cache.
void Preprocessor::EnterSourceFileWithPTH(PTHLexer *PL,
const DirectoryLookup *CurDir) {
if (CurPPLexer || CurTokenLexer)
PushIncludeMacroStack();
CurDirLookup = CurDir;
CurPTHLexer.reset(PL);
CurPPLexer = CurPTHLexer.get();
if (CurLexerKind != CLK_LexAfterModuleImport)
CurLexerKind = CLK_PTHLexer;
// Notify the client, if desired, that we are in a new source file.
if (Callbacks) {
FileID FID = CurPPLexer->getFileID();
SourceLocation EnterLoc = SourceMgr.getLocForStartOfFile(FID);
SrcMgr::CharacteristicKind FileType =
SourceMgr.getFileCharacteristic(EnterLoc);
Callbacks->FileChanged(EnterLoc, PPCallbacks::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(Token &Tok, SourceLocation ILEnd,
MacroInfo *Macro, MacroArgs *Args) {
TokenLexer *TokLexer;
if (NumCachedTokenLexers == 0) {
TokLexer = new TokenLexer(Tok, ILEnd, Macro, Args, *this);
} else {
TokLexer = TokenLexerCache[--NumCachedTokenLexers];
TokLexer->Init(Tok, ILEnd, Macro, Args);
}
PushIncludeMacroStack();
CurDirLookup = 0;
CurTokenLexer.reset(TokLexer);
if (CurLexerKind != CLK_LexAfterModuleImport)
CurLexerKind = CLK_TokenLexer;
}
/// EnterTokenStream - Add a "macro" context to the top of the include stack,
/// which will cause the lexer to start returning the specified tokens.
///
/// If DisableMacroExpansion is true, tokens lexed from the token stream will
/// not be subject to further macro expansion. Otherwise, these tokens will
/// be re-macro-expanded when/if expansion is enabled.
///
/// If OwnsTokens is false, this method assumes that the specified stream of
/// tokens has a permanent owner somewhere, so they do not need to be copied.
/// If it is true, it assumes the array of tokens is allocated with new[] and
/// must be freed.
///
void Preprocessor::EnterTokenStream(const Token *Toks, unsigned NumToks,
bool DisableMacroExpansion,
bool OwnsTokens) {
// Create a macro expander to expand from the specified token stream.
TokenLexer *TokLexer;
if (NumCachedTokenLexers == 0) {
TokLexer = new TokenLexer(Toks, NumToks, DisableMacroExpansion,
OwnsTokens, *this);
} else {
TokLexer = TokenLexerCache[--NumCachedTokenLexers];
TokLexer->Init(Toks, NumToks, DisableMacroExpansion, OwnsTokens);
}
// Save our current state.
PushIncludeMacroStack();
CurDirLookup = 0;
CurTokenLexer.reset(TokLexer);
if (CurLexerKind != CLK_LexAfterModuleImport)
CurLexerKind = CLK_TokenLexer;
}
/// \brief Compute the relative path that names the given file relative to
/// the given directory.
static void computeRelativePath(FileManager &FM, const DirectoryEntry *Dir,
const FileEntry *File,
SmallString<128> &Result) {
Result.clear();
StringRef FilePath = File->getDir()->getName();
StringRef Path = FilePath;
while (!Path.empty()) {
if (const DirectoryEntry *CurDir = FM.getDirectory(Path)) {
if (CurDir == Dir) {
Result = FilePath.substr(Path.size());
llvm::sys::path::append(Result,
llvm::sys::path::filename(File->getName()));
return;
}
}
Path = llvm::sys::path::parent_path(Path);
}
Result = File->getName();
}
void Preprocessor::PropagateLineStartLeadingSpaceInfo(Token &Result) {
if (CurTokenLexer) {
CurTokenLexer->PropagateLineStartLeadingSpaceInfo(Result);
return;
}
if (CurLexer) {
CurLexer->PropagateLineStartLeadingSpaceInfo(Result);
return;
}
// FIXME: Handle other kinds of lexers? It generally shouldn't matter,
// but it might if they're empty?
}
/// 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.
bool Preprocessor::HandleEndOfFile(Token &Result, bool isEndOfMacro) {
assert(!CurTokenLexer &&
"Ending a file when currently in a macro!");
// See if this file had a controlling macro.
if (CurPPLexer) { // Not ending a macro, ignore it.
if (const IdentifierInfo *ControllingMacro =
CurPPLexer->MIOpt.GetControllingMacroAtEndOfFile()) {
// Okay, this has a controlling macro, remember in HeaderFileInfo.
if (const FileEntry *FE =
SourceMgr.getFileEntryForID(CurPPLexer->getFileID())) {
HeaderInfo.SetFileControllingMacro(FE, ControllingMacro);
if (const IdentifierInfo *DefinedMacro =
CurPPLexer->MIOpt.GetDefinedMacro()) {
if (!ControllingMacro->hasMacroDefinition() &&
DefinedMacro != ControllingMacro &&
HeaderInfo.FirstTimeLexingFile(FE)) {
// Emit a warning for a bad header guard.
Diag(CurPPLexer->MIOpt.GetMacroLocation(),
diag::warn_header_guard)
<< CurPPLexer->MIOpt.GetMacroLocation()
<< ControllingMacro;
Diag(CurPPLexer->MIOpt.GetDefinedLocation(),
diag::note_header_guard)
<< CurPPLexer->MIOpt.GetDefinedLocation()
<< DefinedMacro
<< ControllingMacro
<< FixItHint::CreateReplacement(
CurPPLexer->MIOpt.GetDefinedLocation(),
ControllingMacro->getName());
}
}
}
}
}
// Complain about reaching a true EOF within arc_cf_code_audited.
// We don't want to complain about reaching the end of a macro
// instantiation or a _Pragma.
if (PragmaARCCFCodeAuditedLoc.isValid() &&
!isEndOfMacro && !(CurLexer && CurLexer->Is_PragmaLexer)) {
Diag(PragmaARCCFCodeAuditedLoc, diag::err_pp_eof_in_arc_cf_code_audited);
// Recover by leaving immediately.
PragmaARCCFCodeAuditedLoc = SourceLocation();
}
// If this is a #include'd file, pop it off the include stack and continue
// lexing the #includer file.
if (!IncludeMacroStack.empty()) {
// If we lexed the code-completion file, act as if we reached EOF.
if (isCodeCompletionEnabled() && CurPPLexer &&
SourceMgr.getLocForStartOfFile(CurPPLexer->getFileID()) ==
CodeCompletionFileLoc) {
if (CurLexer) {
Result.startToken();
CurLexer->FormTokenWithChars(Result, CurLexer->BufferEnd, tok::eof);
CurLexer.reset();
} else {
assert(CurPTHLexer && "Got EOF but no current lexer set!");
CurPTHLexer->getEOF(Result);
CurPTHLexer.reset();
}
CurPPLexer = 0;
return true;
}
if (!isEndOfMacro && CurPPLexer &&
SourceMgr.getIncludeLoc(CurPPLexer->getFileID()).isValid()) {
// Notify SourceManager to record the number of FileIDs that were created
// during lexing of the #include'd file.
unsigned NumFIDs =
SourceMgr.local_sloc_entry_size() -
CurPPLexer->getInitialNumSLocEntries() + 1/*#include'd file*/;
SourceMgr.setNumCreatedFIDsForFileID(CurPPLexer->getFileID(), NumFIDs);
}
FileID ExitedFID;
if (Callbacks && !isEndOfMacro && CurPPLexer)
ExitedFID = CurPPLexer->getFileID();
// We're done with the #included file.
RemoveTopOfLexerStack();
// Propagate info about start-of-line/leading white-space/etc.
PropagateLineStartLeadingSpaceInfo(Result);
// Notify the client, if desired, that we are in a new source file.
if (Callbacks && !isEndOfMacro && CurPPLexer) {
SrcMgr::CharacteristicKind FileType =
SourceMgr.getFileCharacteristic(CurPPLexer->getSourceLocation());
Callbacks->FileChanged(CurPPLexer->getSourceLocation(),
PPCallbacks::ExitFile, FileType, ExitedFID);
}
// Client should lex another token.
return false;
}
// If the file ends with a newline, form the EOF token on the newline itself,
// rather than "on the line following it", which doesn't exist. This makes
// diagnostics relating to the end of file include the last file that the user
// actually typed, which is goodness.
if (CurLexer) {
const char *EndPos = CurLexer->BufferEnd;
if (EndPos != CurLexer->BufferStart &&
(EndPos[-1] == '\n' || EndPos[-1] == '\r')) {
--EndPos;
// Handle \n\r and \r\n:
if (EndPos != CurLexer->BufferStart &&
(EndPos[-1] == '\n' || EndPos[-1] == '\r') &&
EndPos[-1] != EndPos[0])
--EndPos;
}
Result.startToken();
CurLexer->BufferPtr = EndPos;
CurLexer->FormTokenWithChars(Result, EndPos, tok::eof);
if (isCodeCompletionEnabled()) {
// Inserting the code-completion point increases the source buffer by 1,
// but the main FileID was created before inserting the point.
// Compensate by reducing the EOF location by 1, otherwise the location
// will point to the next FileID.
// FIXME: This is hacky, the code-completion point should probably be
// inserted before the main FileID is created.
if (CurLexer->getFileLoc() == CodeCompletionFileLoc)
Result.setLocation(Result.getLocation().getLocWithOffset(-1));
}
if (!isIncrementalProcessingEnabled())
// We're done with lexing.
CurLexer.reset();
} else {
assert(CurPTHLexer && "Got EOF but no current lexer set!");
CurPTHLexer->getEOF(Result);
CurPTHLexer.reset();
}
if (!isIncrementalProcessingEnabled())
CurPPLexer = 0;
// This is the end of the top-level file. 'WarnUnusedMacroLocs' has collected
// all macro locations that we need to warn because they are not used.
for (WarnUnusedMacroLocsTy::iterator
I=WarnUnusedMacroLocs.begin(), E=WarnUnusedMacroLocs.end(); I!=E; ++I)
Diag(*I, diag::pp_macro_not_used);
// If we are building a module that has an umbrella header, make sure that
// each of the headers within the directory covered by the umbrella header
// was actually included by the umbrella header.
if (Module *Mod = getCurrentModule()) {
if (Mod->getUmbrellaHeader()) {
SourceLocation StartLoc
= SourceMgr.getLocForStartOfFile(SourceMgr.getMainFileID());
if (getDiagnostics().getDiagnosticLevel(
diag::warn_uncovered_module_header,
StartLoc) != DiagnosticsEngine::Ignored) {
ModuleMap &ModMap = getHeaderSearchInfo().getModuleMap();
typedef llvm::sys::fs::recursive_directory_iterator
recursive_directory_iterator;
const DirectoryEntry *Dir = Mod->getUmbrellaDir();
llvm::error_code EC;
for (recursive_directory_iterator Entry(Dir->getName(), EC), End;
Entry != End && !EC; Entry.increment(EC)) {
using llvm::StringSwitch;
// Check whether this entry has an extension typically associated with
// headers.
if (!StringSwitch<bool>(llvm::sys::path::extension(Entry->path()))
.Cases(".h", ".H", ".hh", ".hpp", true)
.Default(false))
continue;
if (const FileEntry *Header = getFileManager().getFile(Entry->path()))
if (!getSourceManager().hasFileInfo(Header)) {
if (!ModMap.isHeaderInUnavailableModule(Header)) {
// Find the relative path that would access this header.
SmallString<128> RelativePath;
computeRelativePath(FileMgr, Dir, Header, RelativePath);
Diag(StartLoc, diag::warn_uncovered_module_header)
<< Mod->getFullModuleName() << RelativePath;
}
}
}
}
}
// Check whether there are any headers that were included, but not
// mentioned at all in the module map. Such headers
SourceLocation StartLoc
= SourceMgr.getLocForStartOfFile(SourceMgr.getMainFileID());
if (getDiagnostics().getDiagnosticLevel(diag::warn_forgotten_module_header,
StartLoc)
!= DiagnosticsEngine::Ignored) {
ModuleMap &ModMap = getHeaderSearchInfo().getModuleMap();
for (unsigned I = 0, N = SourceMgr.local_sloc_entry_size(); I != N; ++I) {
// We only care about file entries.
const SrcMgr::SLocEntry &Entry = SourceMgr.getLocalSLocEntry(I);
if (!Entry.isFile())
continue;
// Dig out the actual file.
const FileEntry *File = Entry.getFile().getContentCache()->OrigEntry;
if (!File)
continue;
// If it's not part of a module and not unknown, complain.
if (!ModMap.findModuleForHeader(File) &&
!ModMap.isHeaderInUnavailableModule(File)) {
Diag(StartLoc, diag::warn_forgotten_module_header)
<< File->getName() << Mod->getFullModuleName();
}
}
}
}
return true;
}
/// HandleEndOfTokenLexer - This callback is invoked when the current TokenLexer
/// hits the end of its token stream.
bool Preprocessor::HandleEndOfTokenLexer(Token &Result) {
assert(CurTokenLexer && !CurPPLexer &&
"Ending a macro when currently in a #include file!");
if (!MacroExpandingLexersStack.empty() &&
MacroExpandingLexersStack.back().first == CurTokenLexer.get())
removeCachedMacroExpandedTokensOfLastLexer();
// Delete or cache the now-dead macro expander.
if (NumCachedTokenLexers == TokenLexerCacheSize)
CurTokenLexer.reset();
else
TokenLexerCache[NumCachedTokenLexers++] = CurTokenLexer.take();
// Handle this like a #include file being popped off the stack.
return HandleEndOfFile(Result, true);
}
/// RemoveTopOfLexerStack - Pop the current lexer/macro exp off the top of the
/// lexer stack. This should only be used in situations where the current
/// state of the top-of-stack lexer is unknown.
void Preprocessor::RemoveTopOfLexerStack() {
assert(!IncludeMacroStack.empty() && "Ran out of stack entries to load");
if (CurTokenLexer) {
// Delete or cache the now-dead macro expander.
if (NumCachedTokenLexers == TokenLexerCacheSize)
CurTokenLexer.reset();
else
TokenLexerCache[NumCachedTokenLexers++] = CurTokenLexer.take();
}
PopIncludeMacroStack();
}
/// HandleMicrosoftCommentPaste - When the macro expander pastes together a
/// comment (/##/) in microsoft mode, this method handles updating the current
/// state, returning the token on the next source line.
void Preprocessor::HandleMicrosoftCommentPaste(Token &Tok) {
assert(CurTokenLexer && !CurPPLexer &&
"Pasted comment can only be formed from macro");
// We handle this by scanning for the closest real lexer, switching it to
// raw mode and preprocessor mode. This will cause it to return \n as an
// explicit EOD token.
PreprocessorLexer *FoundLexer = 0;
bool LexerWasInPPMode = false;
for (unsigned i = 0, e = IncludeMacroStack.size(); i != e; ++i) {
IncludeStackInfo &ISI = *(IncludeMacroStack.end()-i-1);
if (ISI.ThePPLexer == 0) continue; // Scan for a real lexer.
// Once we find a real lexer, mark it as raw mode (disabling macro
// expansions) and preprocessor mode (return EOD). We know that the lexer
// was *not* in raw mode before, because the macro that the comment came
// from was expanded. However, it could have already been in preprocessor
// mode (#if COMMENT) in which case we have to return it to that mode and
// return EOD.
FoundLexer = ISI.ThePPLexer;
FoundLexer->LexingRawMode = true;
LexerWasInPPMode = FoundLexer->ParsingPreprocessorDirective;
FoundLexer->ParsingPreprocessorDirective = true;
break;
}
// Okay, we either found and switched over the lexer, or we didn't find a
// lexer. In either case, finish off the macro the comment came from, getting
// the next token.
if (!HandleEndOfTokenLexer(Tok)) Lex(Tok);
// Discarding comments as long as we don't have EOF or EOD. This 'comments
// out' the rest of the line, including any tokens that came from other macros
// that were active, as in:
// #define submacro a COMMENT b
// submacro c
// which should lex to 'a' only: 'b' and 'c' should be removed.
while (Tok.isNot(tok::eod) && Tok.isNot(tok::eof))
Lex(Tok);
// If we got an eod token, then we successfully found the end of the line.
if (Tok.is(tok::eod)) {
assert(FoundLexer && "Can't get end of line without an active lexer");
// Restore the lexer back to normal mode instead of raw mode.
FoundLexer->LexingRawMode = false;
// If the lexer was already in preprocessor mode, just return the EOD token
// to finish the preprocessor line.
if (LexerWasInPPMode) return;
// Otherwise, switch out of PP mode and return the next lexed token.
FoundLexer->ParsingPreprocessorDirective = false;
return Lex(Tok);
}
// If we got an EOF token, then we reached the end of the token stream but
// didn't find an explicit \n. This can only happen if there was no lexer
// active (an active lexer would return EOD at EOF if there was no \n in
// preprocessor directive mode), so just return EOF as our token.
assert(!FoundLexer && "Lexer should return EOD before EOF in PP mode");
}
Reference in New Issue View Git Blame Copy Permalink