| Current Path : /compat/linux/proc/68247/root/usr/src/contrib/llvm/tools/clang/lib/Frontend/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //compat/linux/proc/68247/root/usr/src/contrib/llvm/tools/clang/lib/Frontend/CacheTokens.cpp |
//===--- CacheTokens.cpp - Caching of lexer tokens for PTH support --------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This provides a possible implementation of PTH support for Clang that is
// based on caching lexed tokens and identifiers.
//
//===----------------------------------------------------------------------===//
#include "clang/Frontend/Utils.h"
#include "clang/Basic/Diagnostic.h"
#include "clang/Basic/FileManager.h"
#include "clang/Basic/FileSystemStatCache.h"
#include "clang/Basic/IdentifierTable.h"
#include "clang/Basic/OnDiskHashTable.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Lex/Lexer.h"
#include "clang/Lex/Preprocessor.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/Path.h"
// FIXME: put this somewhere else?
#ifndef S_ISDIR
#define S_ISDIR(x) (((x)&_S_IFDIR)!=0)
#endif
using namespace clang;
using namespace clang::io;
//===----------------------------------------------------------------------===//
// PTH-specific stuff.
//===----------------------------------------------------------------------===//
namespace {
class PTHEntry {
Offset TokenData, PPCondData;
public:
PTHEntry() {}
PTHEntry(Offset td, Offset ppcd)
: TokenData(td), PPCondData(ppcd) {}
Offset getTokenOffset() const { return TokenData; }
Offset getPPCondTableOffset() const { return PPCondData; }
};
class PTHEntryKeyVariant {
union { const FileEntry* FE; const char* Path; };
enum { IsFE = 0x1, IsDE = 0x2, IsNoExist = 0x0 } Kind;
struct stat *StatBuf;
public:
PTHEntryKeyVariant(const FileEntry *fe)
: FE(fe), Kind(IsFE), StatBuf(0) {}
PTHEntryKeyVariant(struct stat* statbuf, const char* path)
: Path(path), Kind(IsDE), StatBuf(new struct stat(*statbuf)) {}
explicit PTHEntryKeyVariant(const char* path)
: Path(path), Kind(IsNoExist), StatBuf(0) {}
bool isFile() const { return Kind == IsFE; }
StringRef getString() const {
return Kind == IsFE ? FE->getName() : Path;
}
unsigned getKind() const { return (unsigned) Kind; }
void EmitData(raw_ostream& Out) {
switch (Kind) {
case IsFE:
// Emit stat information.
::Emit32(Out, FE->getInode());
::Emit32(Out, FE->getDevice());
::Emit16(Out, FE->getFileMode());
::Emit64(Out, FE->getModificationTime());
::Emit64(Out, FE->getSize());
break;
case IsDE:
// Emit stat information.
::Emit32(Out, (uint32_t) StatBuf->st_ino);
::Emit32(Out, (uint32_t) StatBuf->st_dev);
::Emit16(Out, (uint16_t) StatBuf->st_mode);
::Emit64(Out, (uint64_t) StatBuf->st_mtime);
::Emit64(Out, (uint64_t) StatBuf->st_size);
delete StatBuf;
break;
default:
break;
}
}
unsigned getRepresentationLength() const {
return Kind == IsNoExist ? 0 : 4 + 4 + 2 + 8 + 8;
}
};
class FileEntryPTHEntryInfo {
public:
typedef PTHEntryKeyVariant key_type;
typedef key_type key_type_ref;
typedef PTHEntry data_type;
typedef const PTHEntry& data_type_ref;
static unsigned ComputeHash(PTHEntryKeyVariant V) {
return llvm::HashString(V.getString());
}
static std::pair<unsigned,unsigned>
EmitKeyDataLength(raw_ostream& Out, PTHEntryKeyVariant V,
const PTHEntry& E) {
unsigned n = V.getString().size() + 1 + 1;
::Emit16(Out, n);
unsigned m = V.getRepresentationLength() + (V.isFile() ? 4 + 4 : 0);
::Emit8(Out, m);
return std::make_pair(n, m);
}
static void EmitKey(raw_ostream& Out, PTHEntryKeyVariant V, unsigned n){
// Emit the entry kind.
::Emit8(Out, (unsigned) V.getKind());
// Emit the string.
Out.write(V.getString().data(), n - 1);
}
static void EmitData(raw_ostream& Out, PTHEntryKeyVariant V,
const PTHEntry& E, unsigned) {
// For file entries emit the offsets into the PTH file for token data
// and the preprocessor blocks table.
if (V.isFile()) {
::Emit32(Out, E.getTokenOffset());
::Emit32(Out, E.getPPCondTableOffset());
}
// Emit any other data associated with the key (i.e., stat information).
V.EmitData(Out);
}
};
class OffsetOpt {
bool valid;
Offset off;
public:
OffsetOpt() : valid(false) {}
bool hasOffset() const { return valid; }
Offset getOffset() const { assert(valid); return off; }
void setOffset(Offset o) { off = o; valid = true; }
};
} // end anonymous namespace
typedef OnDiskChainedHashTableGenerator<FileEntryPTHEntryInfo> PTHMap;
namespace {
class PTHWriter {
typedef llvm::DenseMap<const IdentifierInfo*,uint32_t> IDMap;
typedef llvm::StringMap<OffsetOpt, llvm::BumpPtrAllocator> CachedStrsTy;
IDMap IM;
llvm::raw_fd_ostream& Out;
Preprocessor& PP;
uint32_t idcount;
PTHMap PM;
CachedStrsTy CachedStrs;
Offset CurStrOffset;
std::vector<llvm::StringMapEntry<OffsetOpt>*> StrEntries;
//// Get the persistent id for the given IdentifierInfo*.
uint32_t ResolveID(const IdentifierInfo* II);
/// Emit a token to the PTH file.
void EmitToken(const Token& T);
void Emit8(uint32_t V) { ::Emit8(Out, V); }
void Emit16(uint32_t V) { ::Emit16(Out, V); }
void Emit32(uint32_t V) { ::Emit32(Out, V); }
void EmitBuf(const char *Ptr, unsigned NumBytes) {
Out.write(Ptr, NumBytes);
}
void EmitString(StringRef V) {
::Emit16(Out, V.size());
EmitBuf(V.data(), V.size());
}
/// EmitIdentifierTable - Emits two tables to the PTH file. The first is
/// a hashtable mapping from identifier strings to persistent IDs.
/// The second is a straight table mapping from persistent IDs to string data
/// (the keys of the first table).
std::pair<Offset, Offset> EmitIdentifierTable();
/// EmitFileTable - Emit a table mapping from file name strings to PTH
/// token data.
Offset EmitFileTable() { return PM.Emit(Out); }
PTHEntry LexTokens(Lexer& L);
Offset EmitCachedSpellings();
public:
PTHWriter(llvm::raw_fd_ostream& out, Preprocessor& pp)
: Out(out), PP(pp), idcount(0), CurStrOffset(0) {}
PTHMap &getPM() { return PM; }
void GeneratePTH(const std::string &MainFile);
};
} // end anonymous namespace
uint32_t PTHWriter::ResolveID(const IdentifierInfo* II) {
// Null IdentifierInfo's map to the persistent ID 0.
if (!II)
return 0;
IDMap::iterator I = IM.find(II);
if (I != IM.end())
return I->second; // We've already added 1.
IM[II] = ++idcount; // Pre-increment since '0' is reserved for NULL.
return idcount;
}
void PTHWriter::EmitToken(const Token& T) {
// Emit the token kind, flags, and length.
Emit32(((uint32_t) T.getKind()) | ((((uint32_t) T.getFlags())) << 8)|
(((uint32_t) T.getLength()) << 16));
if (!T.isLiteral()) {
Emit32(ResolveID(T.getIdentifierInfo()));
} else {
// We cache *un-cleaned* spellings. This gives us 100% fidelity with the
// source code.
StringRef s(T.getLiteralData(), T.getLength());
// Get the string entry.
llvm::StringMapEntry<OffsetOpt> *E = &CachedStrs.GetOrCreateValue(s);
// If this is a new string entry, bump the PTH offset.
if (!E->getValue().hasOffset()) {
E->getValue().setOffset(CurStrOffset);
StrEntries.push_back(E);
CurStrOffset += s.size() + 1;
}
// Emit the relative offset into the PTH file for the spelling string.
Emit32(E->getValue().getOffset());
}
// Emit the offset into the original source file of this token so that we
// can reconstruct its SourceLocation.
Emit32(PP.getSourceManager().getFileOffset(T.getLocation()));
}
PTHEntry PTHWriter::LexTokens(Lexer& L) {
// Pad 0's so that we emit tokens to a 4-byte alignment.
// This speed up reading them back in.
Pad(Out, 4);
Offset TokenOff = (Offset) Out.tell();
// Keep track of matching '#if' ... '#endif'.
typedef std::vector<std::pair<Offset, unsigned> > PPCondTable;
PPCondTable PPCond;
std::vector<unsigned> PPStartCond;
bool ParsingPreprocessorDirective = false;
Token Tok;
do {
L.LexFromRawLexer(Tok);
NextToken:
if ((Tok.isAtStartOfLine() || Tok.is(tok::eof)) &&
ParsingPreprocessorDirective) {
// Insert an eod token into the token cache. It has the same
// position as the next token that is not on the same line as the
// preprocessor directive. Observe that we continue processing
// 'Tok' when we exit this branch.
Token Tmp = Tok;
Tmp.setKind(tok::eod);
Tmp.clearFlag(Token::StartOfLine);
Tmp.setIdentifierInfo(0);
EmitToken(Tmp);
ParsingPreprocessorDirective = false;
}
if (Tok.is(tok::raw_identifier)) {
PP.LookUpIdentifierInfo(Tok);
EmitToken(Tok);
continue;
}
if (Tok.is(tok::hash) && Tok.isAtStartOfLine()) {
// Special processing for #include. Store the '#' token and lex
// the next token.
assert(!ParsingPreprocessorDirective);
Offset HashOff = (Offset) Out.tell();
// Get the next token.
Token NextTok;
L.LexFromRawLexer(NextTok);
// If we see the start of line, then we had a null directive "#". In
// this case, discard both tokens.
if (NextTok.isAtStartOfLine())
goto NextToken;
// The token is the start of a directive. Emit it.
EmitToken(Tok);
Tok = NextTok;
// Did we see 'include'/'import'/'include_next'?
if (Tok.isNot(tok::raw_identifier)) {
EmitToken(Tok);
continue;
}
IdentifierInfo* II = PP.LookUpIdentifierInfo(Tok);
tok::PPKeywordKind K = II->getPPKeywordID();
ParsingPreprocessorDirective = true;
switch (K) {
case tok::pp_not_keyword:
// Invalid directives "#foo" can occur in #if 0 blocks etc, just pass
// them through.
default:
break;
case tok::pp_include:
case tok::pp_import:
case tok::pp_include_next: {
// Save the 'include' token.
EmitToken(Tok);
// Lex the next token as an include string.
L.setParsingPreprocessorDirective(true);
L.LexIncludeFilename(Tok);
L.setParsingPreprocessorDirective(false);
assert(!Tok.isAtStartOfLine());
if (Tok.is(tok::raw_identifier))
PP.LookUpIdentifierInfo(Tok);
break;
}
case tok::pp_if:
case tok::pp_ifdef:
case tok::pp_ifndef: {
// Add an entry for '#if' and friends. We initially set the target
// index to 0. This will get backpatched when we hit #endif.
PPStartCond.push_back(PPCond.size());
PPCond.push_back(std::make_pair(HashOff, 0U));
break;
}
case tok::pp_endif: {
// Add an entry for '#endif'. We set the target table index to itself.
// This will later be set to zero when emitting to the PTH file. We
// use 0 for uninitialized indices because that is easier to debug.
unsigned index = PPCond.size();
// Backpatch the opening '#if' entry.
assert(!PPStartCond.empty());
assert(PPCond.size() > PPStartCond.back());
assert(PPCond[PPStartCond.back()].second == 0);
PPCond[PPStartCond.back()].second = index;
PPStartCond.pop_back();
// Add the new entry to PPCond.
PPCond.push_back(std::make_pair(HashOff, index));
EmitToken(Tok);
// Some files have gibberish on the same line as '#endif'.
// Discard these tokens.
do
L.LexFromRawLexer(Tok);
while (Tok.isNot(tok::eof) && !Tok.isAtStartOfLine());
// We have the next token in hand.
// Don't immediately lex the next one.
goto NextToken;
}
case tok::pp_elif:
case tok::pp_else: {
// Add an entry for #elif or #else.
// This serves as both a closing and opening of a conditional block.
// This means that its entry will get backpatched later.
unsigned index = PPCond.size();
// Backpatch the previous '#if' entry.
assert(!PPStartCond.empty());
assert(PPCond.size() > PPStartCond.back());
assert(PPCond[PPStartCond.back()].second == 0);
PPCond[PPStartCond.back()].second = index;
PPStartCond.pop_back();
// Now add '#elif' as a new block opening.
PPCond.push_back(std::make_pair(HashOff, 0U));
PPStartCond.push_back(index);
break;
}
}
}
EmitToken(Tok);
}
while (Tok.isNot(tok::eof));
assert(PPStartCond.empty() && "Error: imblanced preprocessor conditionals.");
// Next write out PPCond.
Offset PPCondOff = (Offset) Out.tell();
// Write out the size of PPCond so that clients can identifer empty tables.
Emit32(PPCond.size());
for (unsigned i = 0, e = PPCond.size(); i!=e; ++i) {
Emit32(PPCond[i].first - TokenOff);
uint32_t x = PPCond[i].second;
assert(x != 0 && "PPCond entry not backpatched.");
// Emit zero for #endifs. This allows us to do checking when
// we read the PTH file back in.
Emit32(x == i ? 0 : x);
}
return PTHEntry(TokenOff, PPCondOff);
}
Offset PTHWriter::EmitCachedSpellings() {
// Write each cached strings to the PTH file.
Offset SpellingsOff = Out.tell();
for (std::vector<llvm::StringMapEntry<OffsetOpt>*>::iterator
I = StrEntries.begin(), E = StrEntries.end(); I!=E; ++I)
EmitBuf((*I)->getKeyData(), (*I)->getKeyLength()+1 /*nul included*/);
return SpellingsOff;
}
void PTHWriter::GeneratePTH(const std::string &MainFile) {
// Generate the prologue.
Out << "cfe-pth";
Emit32(PTHManager::Version);
// Leave 4 words for the prologue.
Offset PrologueOffset = Out.tell();
for (unsigned i = 0; i < 4; ++i)
Emit32(0);
// Write the name of the MainFile.
if (!MainFile.empty()) {
EmitString(MainFile);
} else {
// String with 0 bytes.
Emit16(0);
}
Emit8(0);
// Iterate over all the files in SourceManager. Create a lexer
// for each file and cache the tokens.
SourceManager &SM = PP.getSourceManager();
const LangOptions &LOpts = PP.getLangOpts();
for (SourceManager::fileinfo_iterator I = SM.fileinfo_begin(),
E = SM.fileinfo_end(); I != E; ++I) {
const SrcMgr::ContentCache &C = *I->second;
const FileEntry *FE = C.OrigEntry;
// FIXME: Handle files with non-absolute paths.
if (llvm::sys::path::is_relative(FE->getName()))
continue;
const llvm::MemoryBuffer *B = C.getBuffer(PP.getDiagnostics(), SM);
if (!B) continue;
FileID FID = SM.createFileID(FE, SourceLocation(), SrcMgr::C_User);
const llvm::MemoryBuffer *FromFile = SM.getBuffer(FID);
Lexer L(FID, FromFile, SM, LOpts);
PM.insert(FE, LexTokens(L));
}
// Write out the identifier table.
const std::pair<Offset,Offset> &IdTableOff = EmitIdentifierTable();
// Write out the cached strings table.
Offset SpellingOff = EmitCachedSpellings();
// Write out the file table.
Offset FileTableOff = EmitFileTable();
// Finally, write the prologue.
Out.seek(PrologueOffset);
Emit32(IdTableOff.first);
Emit32(IdTableOff.second);
Emit32(FileTableOff);
Emit32(SpellingOff);
}
namespace {
/// StatListener - A simple "interpose" object used to monitor stat calls
/// invoked by FileManager while processing the original sources used
/// as input to PTH generation. StatListener populates the PTHWriter's
/// file map with stat information for directories as well as negative stats.
/// Stat information for files are populated elsewhere.
class StatListener : public FileSystemStatCache {
PTHMap &PM;
public:
StatListener(PTHMap &pm) : PM(pm) {}
~StatListener() {}
LookupResult getStat(const char *Path, struct stat &StatBuf,
int *FileDescriptor) {
LookupResult Result = statChained(Path, StatBuf, FileDescriptor);
if (Result == CacheMissing) // Failed 'stat'.
PM.insert(PTHEntryKeyVariant(Path), PTHEntry());
else if (S_ISDIR(StatBuf.st_mode)) {
// Only cache directories with absolute paths.
if (llvm::sys::path::is_relative(Path))
return Result;
PM.insert(PTHEntryKeyVariant(&StatBuf, Path), PTHEntry());
}
return Result;
}
};
} // end anonymous namespace
void clang::CacheTokens(Preprocessor &PP, llvm::raw_fd_ostream* OS) {
// Get the name of the main file.
const SourceManager &SrcMgr = PP.getSourceManager();
const FileEntry *MainFile = SrcMgr.getFileEntryForID(SrcMgr.getMainFileID());
SmallString<128> MainFilePath(MainFile->getName());
llvm::sys::fs::make_absolute(MainFilePath);
// Create the PTHWriter.
PTHWriter PW(*OS, PP);
// Install the 'stat' system call listener in the FileManager.
StatListener *StatCache = new StatListener(PW.getPM());
PP.getFileManager().addStatCache(StatCache, /*AtBeginning=*/true);
// Lex through the entire file. This will populate SourceManager with
// all of the header information.
Token Tok;
PP.EnterMainSourceFile();
do { PP.Lex(Tok); } while (Tok.isNot(tok::eof));
// Generate the PTH file.
PP.getFileManager().removeStatCache(StatCache);
PW.GeneratePTH(MainFilePath.str());
}
//===----------------------------------------------------------------------===//
namespace {
class PTHIdKey {
public:
const IdentifierInfo* II;
uint32_t FileOffset;
};
class PTHIdentifierTableTrait {
public:
typedef PTHIdKey* key_type;
typedef key_type key_type_ref;
typedef uint32_t data_type;
typedef data_type data_type_ref;
static unsigned ComputeHash(PTHIdKey* key) {
return llvm::HashString(key->II->getName());
}
static std::pair<unsigned,unsigned>
EmitKeyDataLength(raw_ostream& Out, const PTHIdKey* key, uint32_t) {
unsigned n = key->II->getLength() + 1;
::Emit16(Out, n);
return std::make_pair(n, sizeof(uint32_t));
}
static void EmitKey(raw_ostream& Out, PTHIdKey* key, unsigned n) {
// Record the location of the key data. This is used when generating
// the mapping from persistent IDs to strings.
key->FileOffset = Out.tell();
Out.write(key->II->getNameStart(), n);
}
static void EmitData(raw_ostream& Out, PTHIdKey*, uint32_t pID,
unsigned) {
::Emit32(Out, pID);
}
};
} // end anonymous namespace
/// EmitIdentifierTable - Emits two tables to the PTH file. The first is
/// a hashtable mapping from identifier strings to persistent IDs. The second
/// is a straight table mapping from persistent IDs to string data (the
/// keys of the first table).
///
std::pair<Offset,Offset> PTHWriter::EmitIdentifierTable() {
// Build two maps:
// (1) an inverse map from persistent IDs -> (IdentifierInfo*,Offset)
// (2) a map from (IdentifierInfo*, Offset)* -> persistent IDs
// Note that we use 'calloc', so all the bytes are 0.
PTHIdKey *IIDMap = (PTHIdKey*)calloc(idcount, sizeof(PTHIdKey));
// Create the hashtable.
OnDiskChainedHashTableGenerator<PTHIdentifierTableTrait> IIOffMap;
// Generate mapping from persistent IDs -> IdentifierInfo*.
for (IDMap::iterator I = IM.begin(), E = IM.end(); I != E; ++I) {
// Decrement by 1 because we are using a vector for the lookup and
// 0 is reserved for NULL.
assert(I->second > 0);
assert(I->second-1 < idcount);
unsigned idx = I->second-1;
// Store the mapping from persistent ID to IdentifierInfo*
IIDMap[idx].II = I->first;
// Store the reverse mapping in a hashtable.
IIOffMap.insert(&IIDMap[idx], I->second);
}
// Write out the inverse map first. This causes the PCIDKey entries to
// record PTH file offsets for the string data. This is used to write
// the second table.
Offset StringTableOffset = IIOffMap.Emit(Out);
// Now emit the table mapping from persistent IDs to PTH file offsets.
Offset IDOff = Out.tell();
Emit32(idcount); // Emit the number of identifiers.
for (unsigned i = 0 ; i < idcount; ++i)
Emit32(IIDMap[i].FileOffset);
// Finally, release the inverse map.
free(IIDMap);
return std::make_pair(IDOff, StringTableOffset);
}