move IdentifierTable.h from liblex to libbasic.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@42730 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/Basic/IdentifierTable.cpp b/Basic/IdentifierTable.cpp
new file mode 100644
index 0000000..51abcd2
--- /dev/null
+++ b/Basic/IdentifierTable.cpp
@@ -0,0 +1,374 @@
+//===--- IdentifierTable.cpp - Hash table for identifier lookup -----------===//
+//
+// 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 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"
+using namespace clang;
+
+//===----------------------------------------------------------------------===//
+// IdentifierInfo Implementation
+//===----------------------------------------------------------------------===//
+
+IdentifierInfo::IdentifierInfo() {
+ TokenID = tok::identifier;
+ ObjCID = tok::objc_not_keyword;
+ BuiltinID = 0;
+ HasMacro = false;
+ IsExtension = false;
+ IsPoisoned = false;
+ IsOtherTargetMacro = false;
+ IsCPPOperatorKeyword = false;
+ IsNonPortableBuiltin = 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);
+}
+
+//===----------------------------------------------------------------------===//
+// 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,
+ const LangOptions &LangOpts, IdentifierTable &Table) {
+ int Flags = LangOpts.CPlusPlus ? (LangOpts.CPlusPlus0x? CXX0x : CXX)
+ : (LangOpts.C99 ? C99 : 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,
+ 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(AliaseeInfo.getTokenID());
+ 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,
+ 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, LangOpts, *this);
+#define ALIAS(NAME, TOK) \
+ AddAlias(NAME, strlen(NAME), #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();
+ 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);
+ CASE(13, 'd', 'f', define_target);
+ CASE(19, 'd', 'f', define_other_target);
+#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 {
+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);
+}
+
+