diff options
Diffstat (limited to 'lib/Lex/Lexer.cpp')
| -rw-r--r-- | lib/Lex/Lexer.cpp | 288 |
1 files changed, 275 insertions, 13 deletions
diff --git a/lib/Lex/Lexer.cpp b/lib/Lex/Lexer.cpp index 2bd95ab1d7..e6ffca9554 100644 --- a/lib/Lex/Lexer.cpp +++ b/lib/Lex/Lexer.cpp @@ -25,11 +25,13 @@ //===----------------------------------------------------------------------===// #include "clang/Lex/Lexer.h" +#include "clang/Basic/ConvertUTF.h" #include "clang/Basic/SourceManager.h" #include "clang/Lex/CodeCompletionHandler.h" #include "clang/Lex/LexDiagnostic.h" #include "clang/Lex/Preprocessor.h" #include "llvm/ADT/STLExtras.h" +#include "llvm/ADT/StringExtras.h" #include "llvm/ADT/StringSwitch.h" #include "llvm/Support/Compiler.h" #include "llvm/Support/MemoryBuffer.h" @@ -371,10 +373,12 @@ unsigned Lexer::getSpelling(const Token &Tok, const char *&Buffer, // NOTE: this has to be checked *before* testing for an IdentifierInfo. if (Tok.is(tok::raw_identifier)) TokStart = Tok.getRawIdentifierData(); - else if (const IdentifierInfo *II = Tok.getIdentifierInfo()) { - // Just return the string from the identifier table, which is very quick. - Buffer = II->getNameStart(); - return II->getLength(); + else if (!Tok.hasUCN()) { + if (const IdentifierInfo *II = Tok.getIdentifierInfo()) { + // Just return the string from the identifier table, which is very quick. + Buffer = II->getNameStart(); + return II->getLength(); + } } // NOTE: this can be checked even after testing for an IdentifierInfo. @@ -1376,7 +1380,6 @@ SourceLocation Lexer::findLocationAfterToken(SourceLocation Loc, /// 2. If this is an escaped newline (potentially with whitespace between /// the backslash and newline), implicitly skip the newline and return /// the char after it. -/// 3. If this is a UCN, return it. FIXME: C++ UCN's? /// /// This handles the slow/uncommon case of the getCharAndSize method. Here we /// know that we can accumulate into Size, and that we have already incremented @@ -1509,6 +1512,77 @@ void Lexer::SkipBytes(unsigned Bytes, bool StartOfLine) { IsAtStartOfLine = StartOfLine; } +namespace { + struct UCNCharRange { + uint32_t Lower; + uint32_t Upper; + }; + + // C11 D.1, C++11 [charname.allowed] + // FIXME: C99 and C++03 each have a different set of allowed UCNs. + const UCNCharRange UCNAllowedCharRanges[] = { + // 1 + { 0x00A8, 0x00A8 }, { 0x00AA, 0x00AA }, { 0x00AD, 0x00AD }, + { 0x00AF, 0x00AF }, { 0x00B2, 0x00B5 }, { 0x00B7, 0x00BA }, + { 0x00BC, 0x00BE }, { 0x00C0, 0x00D6 }, { 0x00D8, 0x00F6 }, + { 0x00F8, 0x00FF }, + // 2 + { 0x0100, 0x167F }, { 0x1681, 0x180D }, { 0x180F, 0x1FFF }, + // 3 + { 0x200B, 0x200D }, { 0x202A, 0x202E }, { 0x203F, 0x2040 }, + { 0x2054, 0x2054 }, { 0x2060, 0x206F }, + // 4 + { 0x2070, 0x218F }, { 0x2460, 0x24FF }, { 0x2776, 0x2793 }, + { 0x2C00, 0x2DFF }, { 0x2E80, 0x2FFF }, + // 5 + { 0x3004, 0x3007 }, { 0x3021, 0x302F }, { 0x3031, 0x303F }, + // 6 + { 0x3040, 0xD7FF }, + // 7 + { 0xF900, 0xFD3D }, { 0xFD40, 0xFDCF }, { 0xFDF0, 0xFE44 }, + { 0xFE47, 0xFFFD }, + // 8 + { 0x10000, 0x1FFFD }, { 0x20000, 0x2FFFD }, { 0x30000, 0x3FFFD }, + { 0x40000, 0x4FFFD }, { 0x50000, 0x5FFFD }, { 0x60000, 0x6FFFD }, + { 0x70000, 0x7FFFD }, { 0x80000, 0x8FFFD }, { 0x90000, 0x9FFFD }, + { 0xA0000, 0xAFFFD }, { 0xB0000, 0xBFFFD }, { 0xC0000, 0xCFFFD }, + { 0xD0000, 0xDFFFD }, { 0xE0000, 0xEFFFD } + }; +} + +static bool isAllowedIDChar(uint32_t c) { + unsigned LowPoint = 0; + unsigned HighPoint = llvm::array_lengthof(UCNAllowedCharRanges); + + // Binary search the UCNAllowedCharRanges set. + while (HighPoint != LowPoint) { + unsigned MidPoint = (HighPoint + LowPoint) / 2; + if (c < UCNAllowedCharRanges[MidPoint].Lower) + HighPoint = MidPoint; + else if (c > UCNAllowedCharRanges[MidPoint].Upper) + LowPoint = MidPoint + 1; + else + return true; + } + + return false; +} + +static bool isAllowedInitiallyIDChar(uint32_t c) { + // C11 D.2, C++11 [charname.disallowed] + // FIXME: C99 only forbids "digits", presumably as described in C99 Annex D. + // FIXME: C++03 does not forbid any initial characters. + return !(0x0300 <= c && c <= 0x036F) && + !(0x1DC0 <= c && c <= 0x1DFF) && + !(0x20D0 <= c && c <= 0x20FF) && + !(0xFE20 <= c && c <= 0xFE2F); +} + +static inline bool isASCII(char C) { + return static_cast<signed char>(C) >= 0; +} + + void Lexer::LexIdentifier(Token &Result, const char *CurPtr) { // Match [_A-Za-z0-9]*, we have already matched [_A-Za-z$] unsigned Size; @@ -1520,11 +1594,11 @@ void Lexer::LexIdentifier(Token &Result, const char *CurPtr) { // Fast path, no $,\,? in identifier found. '\' might be an escaped newline // or UCN, and ? might be a trigraph for '\', an escaped newline or UCN. - // FIXME: UCNs. // // TODO: Could merge these checks into a CharInfo flag to make the comparison // cheaper - if (C != '\\' && C != '?' && (C != '$' || !LangOpts.DollarIdents)) { + if (isASCII(C) && C != '\\' && C != '?' && + (C != '$' || !LangOpts.DollarIdents)) { FinishIdentifier: const char *IdStart = BufferPtr; FormTokenWithChars(Result, CurPtr, tok::raw_identifier); @@ -1561,8 +1635,38 @@ FinishIdentifier: CurPtr = ConsumeChar(CurPtr, Size, Result); C = getCharAndSize(CurPtr, Size); continue; - } else if (!isIdentifierBody(C)) { // FIXME: UCNs. - // Found end of identifier. + + } else if (C == '\\') { + const char *UCNPtr = CurPtr + Size; + uint32_t CodePoint = tryReadUCN(UCNPtr, CurPtr, /*Token=*/0); + if (CodePoint == 0 || !isAllowedIDChar(CodePoint)) + goto FinishIdentifier; + + Result.setFlag(Token::HasUCN); + if ((UCNPtr - CurPtr == 6 && CurPtr[1] == 'u') || + (UCNPtr - CurPtr == 10 && CurPtr[1] == 'U')) + CurPtr = UCNPtr; + else + while (CurPtr != UCNPtr) + (void)getAndAdvanceChar(CurPtr, Result); + + C = getCharAndSize(CurPtr, Size); + continue; + } else if (!isASCII(C)) { + const char *UnicodePtr = CurPtr; + UTF32 CodePoint; + ConversionResult Result = convertUTF8Sequence((const UTF8 **)&UnicodePtr, + (const UTF8 *)BufferEnd, + &CodePoint, + strictConversion); + if (Result != conversionOK || + !isAllowedIDChar(static_cast<uint32_t>(CodePoint))) + goto FinishIdentifier; + + CurPtr = UnicodePtr; + C = getCharAndSize(CurPtr, Size); + continue; + } else if (!isIdentifierBody(C)) { goto FinishIdentifier; } @@ -1570,7 +1674,7 @@ FinishIdentifier: CurPtr = ConsumeChar(CurPtr, Size, Result); C = getCharAndSize(CurPtr, Size); - while (isIdentifierBody(C)) { // FIXME: UCNs. + while (isIdentifierBody(C)) { CurPtr = ConsumeChar(CurPtr, Size, Result); C = getCharAndSize(CurPtr, Size); } @@ -2592,6 +2696,135 @@ bool Lexer::isCodeCompletionPoint(const char *CurPtr) const { return false; } +uint32_t Lexer::tryReadUCN(const char *&StartPtr, const char *SlashLoc, + Token *Result) { + assert(LangOpts.CPlusPlus || LangOpts.C99); + + unsigned CharSize; + char Kind = getCharAndSize(StartPtr, CharSize); + + unsigned NumHexDigits; + if (Kind == 'u') + NumHexDigits = 4; + else if (Kind == 'U') + NumHexDigits = 8; + else + return 0; + + const char *CurPtr = StartPtr + CharSize; + const char *KindLoc = &CurPtr[-1]; + + uint32_t CodePoint = 0; + for (unsigned i = 0; i < NumHexDigits; ++i) { + char C = getCharAndSize(CurPtr, CharSize); + + unsigned Value = llvm::hexDigitValue(C); + if (Value == -1U) { + if (Result && !isLexingRawMode()) { + if (i == 0) { + Diag(BufferPtr, diag::warn_ucn_escape_no_digits) + << StringRef(KindLoc, 1); + } else { + // FIXME: if i == 4 and NumHexDigits == 8, suggest a fixit to \u. + Diag(BufferPtr, diag::warn_ucn_escape_incomplete); + } + } + + return 0; + } + + CodePoint <<= 4; + CodePoint += Value; + + CurPtr += CharSize; + } + + if (Result) { + Result->setFlag(Token::HasUCN); + if (CurPtr - StartPtr == NumHexDigits + 2) + StartPtr = CurPtr; + else + while (StartPtr != CurPtr) + (void)getAndAdvanceChar(StartPtr, *Result); + } else { + StartPtr = CurPtr; + } + + // C99 6.4.3p2: A universal character name shall not specify a character whose + // short identifier is less than 00A0 other than 0024 ($), 0040 (@), or + // 0060 (`), nor one in the range D800 through DFFF inclusive.) + // C++11 [lex.charset]p2: If the hexadecimal value for a + // universal-character-name corresponds to a surrogate code point (in the + // range 0xD800-0xDFFF, inclusive), the program is ill-formed. Additionally, + // if the hexadecimal value for a universal-character-name outside the + // c-char-sequence, s-char-sequence, or r-char-sequence of a character or + // string literal corresponds to a control character (in either of the + // ranges 0x00-0x1F or 0x7F-0x9F, both inclusive) or to a character in the + // basic source character set, the program is ill-formed. + if (CodePoint < 0xA0) { + if (CodePoint == 0x24 || CodePoint == 0x40 || CodePoint == 0x60) + return CodePoint; + + // We don't use isLexingRawMode() here because we need to warn about bad + // UCNs even when skipping preprocessing tokens in a #if block. + if (Result && PP) { + if (CodePoint < 0x20 || CodePoint >= 0x7F) + Diag(BufferPtr, diag::err_ucn_control_character); + else { + char C = static_cast<char>(CodePoint); + Diag(BufferPtr, diag::err_ucn_escape_basic_scs) << StringRef(&C, 1); + } + } + + return 0; + + } else if ((!LangOpts.CPlusPlus || LangOpts.CPlusPlus11) && + (CodePoint >= 0xD800 && CodePoint <= 0xDFFF)) { + // C++03 allows UCNs representing surrogate characters. C99 and C++11 don't. + // We don't use isLexingRawMode() here because we need to warn about bad + // UCNs even when skipping preprocessing tokens in a #if block. + if (Result && PP) + Diag(BufferPtr, diag::err_ucn_escape_invalid); + return 0; + } + + return CodePoint; +} + +void Lexer::LexUnicode(Token &Result, uint32_t C, const char *CurPtr) { + if (isAllowedIDChar(C) && isAllowedInitiallyIDChar(C)) { + MIOpt.ReadToken(); + return LexIdentifier(Result, CurPtr); + } + + if (!isASCII(*BufferPtr) && !isAllowedIDChar(C)) { + // Non-ASCII characters tend to creep into source code unintentionally. + // Instead of letting the parser complain about the unknown token, + // just drop the character. + // Note that we can /only/ do this when the non-ASCII character is actually + // spelled as Unicode, not written as a UCN. The standard requires that + // we not throw away any possible preprocessor tokens, but there's a + // loophole in the mapping of Unicode characters to basic character set + // characters that allows us to map these particular characters to, say, + // whitespace. + if (!isLexingRawMode()) { + CharSourceRange CharRange = + CharSourceRange::getCharRange(getSourceLocation(), + getSourceLocation(CurPtr)); + Diag(BufferPtr, diag::err_non_ascii) + << FixItHint::CreateRemoval(CharRange); + } + + BufferPtr = CurPtr; + return LexTokenInternal(Result); + } + + // Otherwise, we have an explicit UCN or a character that's unlikely to show + // up by accident. + MIOpt.ReadToken(); + FormTokenWithChars(Result, CurPtr, tok::unknown); +} + /// LexTokenInternal - This implements a simple C family lexer. It is an /// extremely performance critical piece of code. This assumes that the buffer @@ -3243,12 +3476,41 @@ LexNextToken: Kind = tok::unknown; break; + // UCNs (C99 6.4.3, C++11 [lex.charset]p2) case '\\': - // FIXME: UCN's. - // FALL THROUGH. - default: + if (uint32_t CodePoint = tryReadUCN(CurPtr, BufferPtr, &Result)) + return LexUnicode(Result, CodePoint, CurPtr); + Kind = tok::unknown; break; + + default: { + if (isASCII(Char)) { + Kind = tok::unknown; + break; + } + + UTF32 CodePoint; + + // We can't just reset CurPtr to BufferPtr because BufferPtr may point to + // an escaped newline. + --CurPtr; + ConversionResult Status = convertUTF8Sequence((const UTF8 **)&CurPtr, + (const UTF8 *)BufferEnd, + &CodePoint, + strictConversion); + if (Status == conversionOK) + return LexUnicode(Result, CodePoint, CurPtr); + + // Non-ASCII characters tend to creep into source code unintentionally. + // Instead of letting the parser complain about the unknown token, + // just warn that we don't have valid UTF-8, then drop the character. + if (!isLexingRawMode()) + Diag(CurPtr, diag::err_invalid_utf8); + + BufferPtr = CurPtr+1; + goto LexNextToken; + } } // Notify MIOpt that we read a non-whitespace/non-comment token. |