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Diffstat (limited to 'lib/Basic/IdentifierTable.cpp')
| -rw-r--r-- | lib/Basic/IdentifierTable.cpp | 551 |
1 files changed, 551 insertions, 0 deletions
diff --git a/lib/Basic/IdentifierTable.cpp b/lib/Basic/IdentifierTable.cpp new file mode 100644 index 0000000000..65e984a0f7 --- /dev/null +++ b/lib/Basic/IdentifierTable.cpp @@ -0,0 +1,551 @@ +//===--- IdentifierTable.cpp - Hash table for identifier lookup -----------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file implements the IdentifierInfo, IdentifierVisitor, and +// IdentifierTable interfaces. +// +//===----------------------------------------------------------------------===// + +#include "clang/Basic/IdentifierTable.h" +#include "clang/Basic/LangOptions.h" +#include "llvm/ADT/FoldingSet.h" +#include "llvm/ADT/DenseMap.h" +#include "llvm/Bitcode/Serialize.h" +#include "llvm/Bitcode/Deserialize.h" + +using namespace clang; + +//===----------------------------------------------------------------------===// +// IdentifierInfo Implementation +//===----------------------------------------------------------------------===// + +IdentifierInfo::IdentifierInfo() { + TokenID = tok::identifier; + ObjCID = tok::objc_not_keyword; + BuiltinID = 0; + HasMacro = false; + IsExtension = false; + IsPoisoned = false; + IsCPPOperatorKeyword = false; + FETokenInfo = 0; +} + +//===----------------------------------------------------------------------===// +// IdentifierTable Implementation +//===----------------------------------------------------------------------===// + +IdentifierTable::IdentifierTable(const LangOptions &LangOpts) + // Start with space for 8K identifiers. + : HashTable(8192) { + + // Populate the identifier table with info about keywords for the current + // language. + AddKeywords(LangOpts); +} + +// This cstor is intended to be used only for serialization. +IdentifierTable::IdentifierTable() : HashTable(8192) {} + +//===----------------------------------------------------------------------===// +// Language Keyword Implementation +//===----------------------------------------------------------------------===// + +/// AddKeyword - This method is used to associate a token ID with specific +/// identifiers because they are language keywords. This causes the lexer to +/// automatically map matching identifiers to specialized token codes. +/// +/// The C90/C99/CPP/CPP0x flags are set to 0 if the token should be +/// enabled in the specified langauge, set to 1 if it is an extension +/// in the specified language, and set to 2 if disabled in the +/// specified language. +static void AddKeyword(const char *Keyword, unsigned KWLen, + tok::TokenKind TokenCode, + int C90, int C99, int CXX, int CXX0x, int BoolSupport, + const LangOptions &LangOpts, IdentifierTable &Table) { + int Flags = 0; + if (BoolSupport != 0) { + Flags = LangOpts.Boolean ? BoolSupport : 2; + } else if (LangOpts.CPlusPlus) { + Flags = LangOpts.CPlusPlus0x ? CXX0x : CXX; + } else if (LangOpts.C99) { + Flags = C99; + } else { + Flags = C90; + } + + // Don't add this keyword if disabled in this language or if an extension + // and extensions are disabled. + if (Flags + LangOpts.NoExtensions >= 2) return; + + IdentifierInfo &Info = Table.get(Keyword, Keyword+KWLen); + Info.setTokenID(TokenCode); + Info.setIsExtensionToken(Flags == 1); +} + +static void AddAlias(const char *Keyword, unsigned KWLen, + tok::TokenKind AliaseeID, + const char *AliaseeKeyword, unsigned AliaseeKWLen, + const LangOptions &LangOpts, IdentifierTable &Table) { + IdentifierInfo &AliasInfo = Table.get(Keyword, Keyword+KWLen); + IdentifierInfo &AliaseeInfo = Table.get(AliaseeKeyword, + AliaseeKeyword+AliaseeKWLen); + AliasInfo.setTokenID(AliaseeID); + AliasInfo.setIsExtensionToken(AliaseeInfo.isExtensionToken()); +} + +/// AddCXXOperatorKeyword - Register a C++ operator keyword alternative +/// representations. +static void AddCXXOperatorKeyword(const char *Keyword, unsigned KWLen, + tok::TokenKind TokenCode, + IdentifierTable &Table) { + IdentifierInfo &Info = Table.get(Keyword, Keyword + KWLen); + Info.setTokenID(TokenCode); + Info.setIsCPlusPlusOperatorKeyword(); +} + +/// AddObjCKeyword - Register an Objective-C @keyword like "class" "selector" or +/// "property". +static void AddObjCKeyword(tok::ObjCKeywordKind ObjCID, + const char *Name, unsigned NameLen, + IdentifierTable &Table) { + Table.get(Name, Name+NameLen).setObjCKeywordID(ObjCID); +} + +/// AddKeywords - Add all keywords to the symbol table. +/// +void IdentifierTable::AddKeywords(const LangOptions &LangOpts) { + 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, + CPP0xShift = 6, + EXTCPP0x = 1 << CPP0xShift, + NOTCPP0x = 2 << CPP0xShift, + BoolShift = 8, + BOOLSUPPORT = 1 << BoolShift, + Mask = 3 + }; + + // Add keywords and tokens for the current language. +#define KEYWORD(NAME, FLAGS) \ + AddKeyword(#NAME, strlen(#NAME), tok::kw_ ## NAME, \ + ((FLAGS) >> C90Shift) & Mask, \ + ((FLAGS) >> C99Shift) & Mask, \ + ((FLAGS) >> CPPShift) & Mask, \ + ((FLAGS) >> CPP0xShift) & Mask, \ + ((FLAGS) >> BoolShift) & Mask, LangOpts, *this); +#define ALIAS(NAME, TOK) \ + AddAlias(NAME, strlen(NAME), tok::kw_ ## TOK, #TOK, strlen(#TOK), \ + LangOpts, *this); +#define CXX_KEYWORD_OPERATOR(NAME, ALIAS) \ + if (LangOpts.CXXOperatorNames) \ + AddCXXOperatorKeyword(#NAME, strlen(#NAME), tok::ALIAS, *this); +#define OBJC1_AT_KEYWORD(NAME) \ + if (LangOpts.ObjC1) \ + AddObjCKeyword(tok::objc_##NAME, #NAME, strlen(#NAME), *this); +#define OBJC2_AT_KEYWORD(NAME) \ + if (LangOpts.ObjC2) \ + AddObjCKeyword(tok::objc_##NAME, #NAME, strlen(#NAME), *this); +#include "clang/Basic/TokenKinds.def" +} + +tok::PPKeywordKind IdentifierInfo::getPPKeywordID() const { + // We use a perfect hash function here involving the length of the keyword, + // the first and third character. For preprocessor ID's there are no + // collisions (if there were, the switch below would complain about duplicate + // case values). Note that this depends on 'if' being null terminated. + +#define HASH(LEN, FIRST, THIRD) \ + (LEN << 5) + (((FIRST-'a') + (THIRD-'a')) & 31) +#define CASE(LEN, FIRST, THIRD, NAME) \ + case HASH(LEN, FIRST, THIRD): \ + return memcmp(Name, #NAME, LEN) ? tok::pp_not_keyword : tok::pp_ ## NAME + + unsigned Len = getLength(); + if (Len < 2) return tok::pp_not_keyword; + const char *Name = getName(); + switch (HASH(Len, Name[0], Name[2])) { + default: return tok::pp_not_keyword; + CASE( 2, 'i', '\0', if); + CASE( 4, 'e', 'i', elif); + CASE( 4, 'e', 's', else); + CASE( 4, 'l', 'n', line); + CASE( 4, 's', 'c', sccs); + CASE( 5, 'e', 'd', endif); + CASE( 5, 'e', 'r', error); + CASE( 5, 'i', 'e', ident); + CASE( 5, 'i', 'd', ifdef); + CASE( 5, 'u', 'd', undef); + + CASE( 6, 'a', 's', assert); + CASE( 6, 'd', 'f', define); + CASE( 6, 'i', 'n', ifndef); + CASE( 6, 'i', 'p', import); + CASE( 6, 'p', 'a', pragma); + + CASE( 7, 'd', 'f', defined); + CASE( 7, 'i', 'c', include); + CASE( 7, 'w', 'r', warning); + + CASE( 8, 'u', 'a', unassert); + CASE(12, 'i', 'c', include_next); +#undef CASE +#undef HASH + } +} + +//===----------------------------------------------------------------------===// +// Stats Implementation +//===----------------------------------------------------------------------===// + +/// PrintStats - Print statistics about how well the identifier table is doing +/// at hashing identifiers. +void IdentifierTable::PrintStats() const { + unsigned NumBuckets = HashTable.getNumBuckets(); + unsigned NumIdentifiers = HashTable.getNumItems(); + unsigned NumEmptyBuckets = NumBuckets-NumIdentifiers; + unsigned AverageIdentifierSize = 0; + unsigned MaxIdentifierLength = 0; + + // TODO: Figure out maximum times an identifier had to probe for -stats. + for (llvm::StringMap<IdentifierInfo, llvm::BumpPtrAllocator>::const_iterator + I = HashTable.begin(), E = HashTable.end(); I != E; ++I) { + unsigned IdLen = I->getKeyLength(); + AverageIdentifierSize += IdLen; + if (MaxIdentifierLength < IdLen) + MaxIdentifierLength = IdLen; + } + + fprintf(stderr, "\n*** Identifier Table Stats:\n"); + fprintf(stderr, "# Identifiers: %d\n", NumIdentifiers); + fprintf(stderr, "# Empty Buckets: %d\n", NumEmptyBuckets); + fprintf(stderr, "Hash density (#identifiers per bucket): %f\n", + NumIdentifiers/(double)NumBuckets); + fprintf(stderr, "Ave identifier length: %f\n", + (AverageIdentifierSize/(double)NumIdentifiers)); + fprintf(stderr, "Max identifier length: %d\n", MaxIdentifierLength); + + // Compute statistics about the memory allocated for identifiers. + HashTable.getAllocator().PrintStats(); +} + +//===----------------------------------------------------------------------===// +// SelectorTable Implementation +//===----------------------------------------------------------------------===// + +unsigned llvm::DenseMapInfo<clang::Selector>::getHashValue(clang::Selector S) { + return DenseMapInfo<void*>::getHashValue(S.getAsOpaquePtr()); +} + + +/// MultiKeywordSelector - One of these variable length records is kept for each +/// selector containing more than one keyword. We use a folding set +/// to unique aggregate names (keyword selectors in ObjC parlance). Access to +/// this class is provided strictly through Selector. +namespace clang { +class MultiKeywordSelector : public llvm::FoldingSetNode { + friend SelectorTable* SelectorTable::CreateAndRegister(llvm::Deserializer&); + MultiKeywordSelector(unsigned nKeys) : NumArgs(nKeys) {} +public: + unsigned NumArgs; + + // Constructor for keyword selectors. + MultiKeywordSelector(unsigned nKeys, IdentifierInfo **IIV) { + assert((nKeys > 1) && "not a multi-keyword selector"); + NumArgs = nKeys; + + // Fill in the trailing keyword array. + IdentifierInfo **KeyInfo = reinterpret_cast<IdentifierInfo **>(this+1); + for (unsigned i = 0; i != nKeys; ++i) + KeyInfo[i] = IIV[i]; + } + + // getName - Derive the full selector name and return it. + std::string getName() const; + + unsigned getNumArgs() const { return NumArgs; } + + typedef IdentifierInfo *const *keyword_iterator; + keyword_iterator keyword_begin() const { + return reinterpret_cast<keyword_iterator>(this+1); + } + keyword_iterator keyword_end() const { + return keyword_begin()+NumArgs; + } + IdentifierInfo *getIdentifierInfoForSlot(unsigned i) const { + assert(i < NumArgs && "getIdentifierInfoForSlot(): illegal index"); + return keyword_begin()[i]; + } + static void Profile(llvm::FoldingSetNodeID &ID, + keyword_iterator ArgTys, unsigned NumArgs) { + ID.AddInteger(NumArgs); + for (unsigned i = 0; i != NumArgs; ++i) + ID.AddPointer(ArgTys[i]); + } + void Profile(llvm::FoldingSetNodeID &ID) { + Profile(ID, keyword_begin(), NumArgs); + } +}; +} // end namespace clang. + +unsigned Selector::getNumArgs() const { + unsigned IIF = getIdentifierInfoFlag(); + if (IIF == ZeroArg) + return 0; + if (IIF == OneArg) + return 1; + // We point to a MultiKeywordSelector (pointer doesn't contain any flags). + MultiKeywordSelector *SI = reinterpret_cast<MultiKeywordSelector *>(InfoPtr); + return SI->getNumArgs(); +} + +IdentifierInfo *Selector::getIdentifierInfoForSlot(unsigned argIndex) const { + if (IdentifierInfo *II = getAsIdentifierInfo()) { + assert(argIndex == 0 && "illegal keyword index"); + return II; + } + // We point to a MultiKeywordSelector (pointer doesn't contain any flags). + MultiKeywordSelector *SI = reinterpret_cast<MultiKeywordSelector *>(InfoPtr); + return SI->getIdentifierInfoForSlot(argIndex); +} + +std::string MultiKeywordSelector::getName() const { + std::string Result; + unsigned Length = 0; + for (keyword_iterator I = keyword_begin(), E = keyword_end(); I != E; ++I) { + if (*I) + Length += (*I)->getLength(); + ++Length; // : + } + + Result.reserve(Length); + + for (keyword_iterator I = keyword_begin(), E = keyword_end(); I != E; ++I) { + if (*I) + Result.insert(Result.end(), (*I)->getName(), + (*I)->getName()+(*I)->getLength()); + Result.push_back(':'); + } + + return Result; +} + +std::string Selector::getName() const { + if (IdentifierInfo *II = getAsIdentifierInfo()) { + if (getNumArgs() == 0) + return II->getName(); + + std::string Res = II->getName(); + Res += ":"; + return Res; + } + + // We have a multiple keyword selector (no embedded flags). + return reinterpret_cast<MultiKeywordSelector *>(InfoPtr)->getName(); +} + + +Selector SelectorTable::getSelector(unsigned nKeys, IdentifierInfo **IIV) { + if (nKeys < 2) + return Selector(IIV[0], nKeys); + + llvm::FoldingSet<MultiKeywordSelector> *SelTab; + + SelTab = static_cast<llvm::FoldingSet<MultiKeywordSelector> *>(Impl); + + // Unique selector, to guarantee there is one per name. + llvm::FoldingSetNodeID ID; + MultiKeywordSelector::Profile(ID, IIV, nKeys); + + void *InsertPos = 0; + if (MultiKeywordSelector *SI = SelTab->FindNodeOrInsertPos(ID, InsertPos)) + return Selector(SI); + + // MultiKeywordSelector objects are not allocated with new because they have a + // variable size array (for parameter types) at the end of them. + MultiKeywordSelector *SI = + (MultiKeywordSelector*)malloc(sizeof(MultiKeywordSelector) + + nKeys*sizeof(IdentifierInfo *)); + new (SI) MultiKeywordSelector(nKeys, IIV); + SelTab->InsertNode(SI, InsertPos); + return Selector(SI); +} + +SelectorTable::SelectorTable() { + Impl = new llvm::FoldingSet<MultiKeywordSelector>; +} + +SelectorTable::~SelectorTable() { + delete static_cast<llvm::FoldingSet<MultiKeywordSelector> *>(Impl); +} + +//===----------------------------------------------------------------------===// +// Serialization for IdentifierInfo and IdentifierTable. +//===----------------------------------------------------------------------===// + +void IdentifierInfo::Emit(llvm::Serializer& S) const { + S.EmitInt(getTokenID()); + S.EmitInt(getBuiltinID()); + S.EmitInt(getObjCKeywordID()); + S.EmitBool(hasMacroDefinition()); + S.EmitBool(isExtensionToken()); + S.EmitBool(isPoisoned()); + S.EmitBool(isCPlusPlusOperatorKeyword()); + // FIXME: FETokenInfo +} + +void IdentifierInfo::Read(llvm::Deserializer& D) { + setTokenID((tok::TokenKind) D.ReadInt()); + setBuiltinID(D.ReadInt()); + setObjCKeywordID((tok::ObjCKeywordKind) D.ReadInt()); + setHasMacroDefinition(D.ReadBool()); + setIsExtensionToken(D.ReadBool()); + setIsPoisoned(D.ReadBool()); + setIsCPlusPlusOperatorKeyword(D.ReadBool()); + // FIXME: FETokenInfo +} + +void IdentifierTable::Emit(llvm::Serializer& S) const { + S.EnterBlock(); + + S.EmitPtr(this); + + for (iterator I=begin(), E=end(); I != E; ++I) { + const char* Key = I->getKeyData(); + const IdentifierInfo* Info = &I->getValue(); + + bool KeyRegistered = S.isRegistered(Key); + bool InfoRegistered = S.isRegistered(Info); + + if (KeyRegistered || InfoRegistered) { + // These acrobatics are so that we don't incur the cost of registering + // a pointer with the backpatcher during deserialization if nobody + // references the object. + S.EmitPtr(InfoRegistered ? Info : NULL); + S.EmitPtr(KeyRegistered ? Key : NULL); + S.EmitCStr(Key); + S.Emit(*Info); + } + } + + S.ExitBlock(); +} + +IdentifierTable* IdentifierTable::CreateAndRegister(llvm::Deserializer& D) { + llvm::Deserializer::Location BLoc = D.getCurrentBlockLocation(); + + std::vector<char> buff; + buff.reserve(200); + + IdentifierTable* t = new IdentifierTable(); + D.RegisterPtr(t); + + while (!D.FinishedBlock(BLoc)) { + llvm::SerializedPtrID InfoPtrID = D.ReadPtrID(); + llvm::SerializedPtrID KeyPtrID = D.ReadPtrID(); + + D.ReadCStr(buff); + + llvm::StringMapEntry<IdentifierInfo>& Entry = + t->HashTable.GetOrCreateValue(&buff[0],&buff[0]+buff.size()); + + D.Read(Entry.getValue()); + + if (InfoPtrID) + D.RegisterRef(InfoPtrID,Entry.getValue()); + + if (KeyPtrID) + D.RegisterPtr(KeyPtrID,Entry.getKeyData()); + } + + return t; +} + +//===----------------------------------------------------------------------===// +// Serialization for Selector and SelectorTable. +//===----------------------------------------------------------------------===// + +void Selector::Emit(llvm::Serializer& S) const { + S.EmitInt(getIdentifierInfoFlag()); + S.EmitPtr(reinterpret_cast<void*>(InfoPtr & ~ArgFlags)); +} + +Selector Selector::ReadVal(llvm::Deserializer& D) { + unsigned flag = D.ReadInt(); + + uintptr_t ptr; + D.ReadUIntPtr(ptr,false); // No backpatching. + + return Selector(ptr | flag); +} + +void SelectorTable::Emit(llvm::Serializer& S) const { + typedef llvm::FoldingSet<MultiKeywordSelector>::iterator iterator; + llvm::FoldingSet<MultiKeywordSelector> *SelTab; + SelTab = static_cast<llvm::FoldingSet<MultiKeywordSelector> *>(Impl); + + S.EnterBlock(); + + S.EmitPtr(this); + + for (iterator I=SelTab->begin(), E=SelTab->end(); I != E; ++I) { + if (!S.isRegistered(&*I)) + continue; + + S.FlushRecord(); // Start a new record. + + S.EmitPtr(&*I); + S.EmitInt(I->getNumArgs()); + + for (MultiKeywordSelector::keyword_iterator KI = I->keyword_begin(), + KE = I->keyword_end(); KI != KE; ++KI) + S.EmitPtr(*KI); + } + + S.ExitBlock(); +} + +SelectorTable* SelectorTable::CreateAndRegister(llvm::Deserializer& D) { + llvm::Deserializer::Location BLoc = D.getCurrentBlockLocation(); + + SelectorTable* t = new SelectorTable(); + D.RegisterPtr(t); + + llvm::FoldingSet<MultiKeywordSelector>& SelTab = + *static_cast<llvm::FoldingSet<MultiKeywordSelector>*>(t->Impl); + + while (!D.FinishedBlock(BLoc)) { + + llvm::SerializedPtrID PtrID = D.ReadPtrID(); + unsigned nKeys = D.ReadInt(); + + MultiKeywordSelector *SI = + (MultiKeywordSelector*)malloc(sizeof(MultiKeywordSelector) + + nKeys*sizeof(IdentifierInfo *)); + + new (SI) MultiKeywordSelector(nKeys); + + D.RegisterPtr(PtrID,SI); + + IdentifierInfo **KeyInfo = reinterpret_cast<IdentifierInfo **>(SI+1); + + for (unsigned i = 0; i != nKeys; ++i) + D.ReadPtr(KeyInfo[i],false); + + SelTab.GetOrInsertNode(SI); + } + + return t; +} |