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Diffstat (limited to 'clang/lib/Lex/LiteralSupport.cpp')
| -rw-r--r-- | clang/lib/Lex/LiteralSupport.cpp | 1896 |
1 files changed, 1896 insertions, 0 deletions
diff --git a/clang/lib/Lex/LiteralSupport.cpp b/clang/lib/Lex/LiteralSupport.cpp new file mode 100644 index 000000000000..2108408377fb --- /dev/null +++ b/clang/lib/Lex/LiteralSupport.cpp @@ -0,0 +1,1896 @@ +//===--- LiteralSupport.cpp - Code to parse and process literals ----------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +// +// This file implements the NumericLiteralParser, CharLiteralParser, and +// StringLiteralParser interfaces. +// +//===----------------------------------------------------------------------===// + +#include "clang/Lex/LiteralSupport.h" +#include "clang/Basic/CharInfo.h" +#include "clang/Basic/LangOptions.h" +#include "clang/Basic/SourceLocation.h" +#include "clang/Basic/TargetInfo.h" +#include "clang/Lex/LexDiagnostic.h" +#include "clang/Lex/Lexer.h" +#include "clang/Lex/Preprocessor.h" +#include "clang/Lex/Token.h" +#include "llvm/ADT/APInt.h" +#include "llvm/ADT/SmallVector.h" +#include "llvm/ADT/StringExtras.h" +#include "llvm/ADT/StringSwitch.h" +#include "llvm/Support/ConvertUTF.h" +#include "llvm/Support/ErrorHandling.h" +#include <algorithm> +#include <cassert> +#include <cstddef> +#include <cstdint> +#include <cstring> +#include <string> + +using namespace clang; + +static unsigned getCharWidth(tok::TokenKind kind, const TargetInfo &Target) { + switch (kind) { + default: llvm_unreachable("Unknown token type!"); + case tok::char_constant: + case tok::string_literal: + case tok::utf8_char_constant: + case tok::utf8_string_literal: + return Target.getCharWidth(); + case tok::wide_char_constant: + case tok::wide_string_literal: + return Target.getWCharWidth(); + case tok::utf16_char_constant: + case tok::utf16_string_literal: + return Target.getChar16Width(); + case tok::utf32_char_constant: + case tok::utf32_string_literal: + return Target.getChar32Width(); + } +} + +static CharSourceRange MakeCharSourceRange(const LangOptions &Features, + FullSourceLoc TokLoc, + const char *TokBegin, + const char *TokRangeBegin, + const char *TokRangeEnd) { + SourceLocation Begin = + Lexer::AdvanceToTokenCharacter(TokLoc, TokRangeBegin - TokBegin, + TokLoc.getManager(), Features); + SourceLocation End = + Lexer::AdvanceToTokenCharacter(Begin, TokRangeEnd - TokRangeBegin, + TokLoc.getManager(), Features); + return CharSourceRange::getCharRange(Begin, End); +} + +/// Produce a diagnostic highlighting some portion of a literal. +/// +/// Emits the diagnostic \p DiagID, highlighting the range of characters from +/// \p TokRangeBegin (inclusive) to \p TokRangeEnd (exclusive), which must be +/// a substring of a spelling buffer for the token beginning at \p TokBegin. +static DiagnosticBuilder Diag(DiagnosticsEngine *Diags, + const LangOptions &Features, FullSourceLoc TokLoc, + const char *TokBegin, const char *TokRangeBegin, + const char *TokRangeEnd, unsigned DiagID) { + SourceLocation Begin = + Lexer::AdvanceToTokenCharacter(TokLoc, TokRangeBegin - TokBegin, + TokLoc.getManager(), Features); + return Diags->Report(Begin, DiagID) << + MakeCharSourceRange(Features, TokLoc, TokBegin, TokRangeBegin, TokRangeEnd); +} + +/// ProcessCharEscape - Parse a standard C escape sequence, which can occur in +/// either a character or a string literal. +static unsigned ProcessCharEscape(const char *ThisTokBegin, + const char *&ThisTokBuf, + const char *ThisTokEnd, bool &HadError, + FullSourceLoc Loc, unsigned CharWidth, + DiagnosticsEngine *Diags, + const LangOptions &Features) { + const char *EscapeBegin = ThisTokBuf; + + // Skip the '\' char. + ++ThisTokBuf; + + // We know that this character can't be off the end of the buffer, because + // that would have been \", which would not have been the end of string. + unsigned ResultChar = *ThisTokBuf++; + switch (ResultChar) { + // These map to themselves. + case '\\': case '\'': case '"': case '?': break; + + // These have fixed mappings. + case 'a': + // TODO: K&R: the meaning of '\\a' is different in traditional C + ResultChar = 7; + break; + case 'b': + ResultChar = 8; + break; + case 'e': + if (Diags) + Diag(Diags, Features, Loc, ThisTokBegin, EscapeBegin, ThisTokBuf, + diag::ext_nonstandard_escape) << "e"; + ResultChar = 27; + break; + case 'E': + if (Diags) + Diag(Diags, Features, Loc, ThisTokBegin, EscapeBegin, ThisTokBuf, + diag::ext_nonstandard_escape) << "E"; + ResultChar = 27; + break; + case 'f': + ResultChar = 12; + break; + case 'n': + ResultChar = 10; + break; + case 'r': + ResultChar = 13; + break; + case 't': + ResultChar = 9; + break; + case 'v': + ResultChar = 11; + break; + case 'x': { // Hex escape. + ResultChar = 0; + if (ThisTokBuf == ThisTokEnd || !isHexDigit(*ThisTokBuf)) { + if (Diags) + Diag(Diags, Features, Loc, ThisTokBegin, EscapeBegin, ThisTokBuf, + diag::err_hex_escape_no_digits) << "x"; + HadError = true; + break; + } + + // Hex escapes are a maximal series of hex digits. + bool Overflow = false; + for (; ThisTokBuf != ThisTokEnd; ++ThisTokBuf) { + int CharVal = llvm::hexDigitValue(ThisTokBuf[0]); + if (CharVal == -1) break; + // About to shift out a digit? + if (ResultChar & 0xF0000000) + Overflow = true; + ResultChar <<= 4; + ResultChar |= CharVal; + } + + // See if any bits will be truncated when evaluated as a character. + if (CharWidth != 32 && (ResultChar >> CharWidth) != 0) { + Overflow = true; + ResultChar &= ~0U >> (32-CharWidth); + } + + // Check for overflow. + if (Overflow && Diags) // Too many digits to fit in + Diag(Diags, Features, Loc, ThisTokBegin, EscapeBegin, ThisTokBuf, + diag::err_escape_too_large) << 0; + break; + } + case '0': case '1': case '2': case '3': + case '4': case '5': case '6': case '7': { + // Octal escapes. + --ThisTokBuf; + ResultChar = 0; + + // Octal escapes are a series of octal digits with maximum length 3. + // "\0123" is a two digit sequence equal to "\012" "3". + unsigned NumDigits = 0; + do { + ResultChar <<= 3; + ResultChar |= *ThisTokBuf++ - '0'; + ++NumDigits; + } while (ThisTokBuf != ThisTokEnd && NumDigits < 3 && + ThisTokBuf[0] >= '0' && ThisTokBuf[0] <= '7'); + + // Check for overflow. Reject '\777', but not L'\777'. + if (CharWidth != 32 && (ResultChar >> CharWidth) != 0) { + if (Diags) + Diag(Diags, Features, Loc, ThisTokBegin, EscapeBegin, ThisTokBuf, + diag::err_escape_too_large) << 1; + ResultChar &= ~0U >> (32-CharWidth); + } + break; + } + + // Otherwise, these are not valid escapes. + case '(': case '{': case '[': case '%': + // GCC accepts these as extensions. We warn about them as such though. + if (Diags) + Diag(Diags, Features, Loc, ThisTokBegin, EscapeBegin, ThisTokBuf, + diag::ext_nonstandard_escape) + << std::string(1, ResultChar); + break; + default: + if (!Diags) + break; + + if (isPrintable(ResultChar)) + Diag(Diags, Features, Loc, ThisTokBegin, EscapeBegin, ThisTokBuf, + diag::ext_unknown_escape) + << std::string(1, ResultChar); + else + Diag(Diags, Features, Loc, ThisTokBegin, EscapeBegin, ThisTokBuf, + diag::ext_unknown_escape) + << "x" + llvm::utohexstr(ResultChar); + break; + } + + return ResultChar; +} + +static void appendCodePoint(unsigned Codepoint, + llvm::SmallVectorImpl<char> &Str) { + char ResultBuf[4]; + char *ResultPtr = ResultBuf; + bool Res = llvm::ConvertCodePointToUTF8(Codepoint, ResultPtr); + (void)Res; + assert(Res && "Unexpected conversion failure"); + Str.append(ResultBuf, ResultPtr); +} + +void clang::expandUCNs(SmallVectorImpl<char> &Buf, StringRef Input) { + for (StringRef::iterator I = Input.begin(), E = Input.end(); I != E; ++I) { + if (*I != '\\') { + Buf.push_back(*I); + continue; + } + + ++I; + assert(*I == 'u' || *I == 'U'); + + unsigned NumHexDigits; + if (*I == 'u') + NumHexDigits = 4; + else + NumHexDigits = 8; + + assert(I + NumHexDigits <= E); + + uint32_t CodePoint = 0; + for (++I; NumHexDigits != 0; ++I, --NumHexDigits) { + unsigned Value = llvm::hexDigitValue(*I); + assert(Value != -1U); + + CodePoint <<= 4; + CodePoint += Value; + } + + appendCodePoint(CodePoint, Buf); + --I; + } +} + +/// ProcessUCNEscape - Read the Universal Character Name, check constraints and +/// return the UTF32. +static bool ProcessUCNEscape(const char *ThisTokBegin, const char *&ThisTokBuf, + const char *ThisTokEnd, + uint32_t &UcnVal, unsigned short &UcnLen, + FullSourceLoc Loc, DiagnosticsEngine *Diags, + const LangOptions &Features, + bool in_char_string_literal = false) { + const char *UcnBegin = ThisTokBuf; + + // Skip the '\u' char's. + ThisTokBuf += 2; + + if (ThisTokBuf == ThisTokEnd || !isHexDigit(*ThisTokBuf)) { + if (Diags) + Diag(Diags, Features, Loc, ThisTokBegin, UcnBegin, ThisTokBuf, + diag::err_hex_escape_no_digits) << StringRef(&ThisTokBuf[-1], 1); + return false; + } + UcnLen = (ThisTokBuf[-1] == 'u' ? 4 : 8); + unsigned short UcnLenSave = UcnLen; + for (; ThisTokBuf != ThisTokEnd && UcnLenSave; ++ThisTokBuf, UcnLenSave--) { + int CharVal = llvm::hexDigitValue(ThisTokBuf[0]); + if (CharVal == -1) break; + UcnVal <<= 4; + UcnVal |= CharVal; + } + // If we didn't consume the proper number of digits, there is a problem. + if (UcnLenSave) { + if (Diags) + Diag(Diags, Features, Loc, ThisTokBegin, UcnBegin, ThisTokBuf, + diag::err_ucn_escape_incomplete); + return false; + } + + // Check UCN constraints (C99 6.4.3p2) [C++11 lex.charset p2] + if ((0xD800 <= UcnVal && UcnVal <= 0xDFFF) || // surrogate codepoints + UcnVal > 0x10FFFF) { // maximum legal UTF32 value + if (Diags) + Diag(Diags, Features, Loc, ThisTokBegin, UcnBegin, ThisTokBuf, + diag::err_ucn_escape_invalid); + return false; + } + + // C++11 allows UCNs that refer to control characters and basic source + // characters inside character and string literals + if (UcnVal < 0xa0 && + (UcnVal != 0x24 && UcnVal != 0x40 && UcnVal != 0x60)) { // $, @, ` + bool IsError = (!Features.CPlusPlus11 || !in_char_string_literal); + if (Diags) { + char BasicSCSChar = UcnVal; + if (UcnVal >= 0x20 && UcnVal < 0x7f) + Diag(Diags, Features, Loc, ThisTokBegin, UcnBegin, ThisTokBuf, + IsError ? diag::err_ucn_escape_basic_scs : + diag::warn_cxx98_compat_literal_ucn_escape_basic_scs) + << StringRef(&BasicSCSChar, 1); + else + Diag(Diags, Features, Loc, ThisTokBegin, UcnBegin, ThisTokBuf, + IsError ? diag::err_ucn_control_character : + diag::warn_cxx98_compat_literal_ucn_control_character); + } + if (IsError) + return false; + } + + if (!Features.CPlusPlus && !Features.C99 && Diags) + Diag(Diags, Features, Loc, ThisTokBegin, UcnBegin, ThisTokBuf, + diag::warn_ucn_not_valid_in_c89_literal); + + return true; +} + +/// MeasureUCNEscape - Determine the number of bytes within the resulting string +/// which this UCN will occupy. +static int MeasureUCNEscape(const char *ThisTokBegin, const char *&ThisTokBuf, + const char *ThisTokEnd, unsigned CharByteWidth, + const LangOptions &Features, bool &HadError) { + // UTF-32: 4 bytes per escape. + if (CharByteWidth == 4) + return 4; + + uint32_t UcnVal = 0; + unsigned short UcnLen = 0; + FullSourceLoc Loc; + + if (!ProcessUCNEscape(ThisTokBegin, ThisTokBuf, ThisTokEnd, UcnVal, + UcnLen, Loc, nullptr, Features, true)) { + HadError = true; + return 0; + } + + // UTF-16: 2 bytes for BMP, 4 bytes otherwise. + if (CharByteWidth == 2) + return UcnVal <= 0xFFFF ? 2 : 4; + + // UTF-8. + if (UcnVal < 0x80) + return 1; + if (UcnVal < 0x800) + return 2; + if (UcnVal < 0x10000) + return 3; + return 4; +} + +/// EncodeUCNEscape - Read the Universal Character Name, check constraints and +/// convert the UTF32 to UTF8 or UTF16. This is a subroutine of +/// StringLiteralParser. When we decide to implement UCN's for identifiers, +/// we will likely rework our support for UCN's. +static void EncodeUCNEscape(const char *ThisTokBegin, const char *&ThisTokBuf, + const char *ThisTokEnd, + char *&ResultBuf, bool &HadError, + FullSourceLoc Loc, unsigned CharByteWidth, + DiagnosticsEngine *Diags, + const LangOptions &Features) { + typedef uint32_t UTF32; + UTF32 UcnVal = 0; + unsigned short UcnLen = 0; + if (!ProcessUCNEscape(ThisTokBegin, ThisTokBuf, ThisTokEnd, UcnVal, UcnLen, + Loc, Diags, Features, true)) { + HadError = true; + return; + } + + assert((CharByteWidth == 1 || CharByteWidth == 2 || CharByteWidth == 4) && + "only character widths of 1, 2, or 4 bytes supported"); + + (void)UcnLen; + assert((UcnLen== 4 || UcnLen== 8) && "only ucn length of 4 or 8 supported"); + + if (CharByteWidth == 4) { + // FIXME: Make the type of the result buffer correct instead of + // using reinterpret_cast. + llvm::UTF32 *ResultPtr = reinterpret_cast<llvm::UTF32*>(ResultBuf); + *ResultPtr = UcnVal; + ResultBuf += 4; + return; + } + + if (CharByteWidth == 2) { + // FIXME: Make the type of the result buffer correct instead of + // using reinterpret_cast. + llvm::UTF16 *ResultPtr = reinterpret_cast<llvm::UTF16*>(ResultBuf); + + if (UcnVal <= (UTF32)0xFFFF) { + *ResultPtr = UcnVal; + ResultBuf += 2; + return; + } + + // Convert to UTF16. + UcnVal -= 0x10000; + *ResultPtr = 0xD800 + (UcnVal >> 10); + *(ResultPtr+1) = 0xDC00 + (UcnVal & 0x3FF); + ResultBuf += 4; + return; + } + + assert(CharByteWidth == 1 && "UTF-8 encoding is only for 1 byte characters"); + + // Now that we've parsed/checked the UCN, we convert from UTF32->UTF8. + // The conversion below was inspired by: + // http://www.unicode.org/Public/PROGRAMS/CVTUTF/ConvertUTF.c + // First, we determine how many bytes the result will require. + typedef uint8_t UTF8; + + unsigned short bytesToWrite = 0; + if (UcnVal < (UTF32)0x80) + bytesToWrite = 1; + else if (UcnVal < (UTF32)0x800) + bytesToWrite = 2; + else if (UcnVal < (UTF32)0x10000) + bytesToWrite = 3; + else + bytesToWrite = 4; + + const unsigned byteMask = 0xBF; + const unsigned byteMark = 0x80; + + // Once the bits are split out into bytes of UTF8, this is a mask OR-ed + // into the first byte, depending on how many bytes follow. + static const UTF8 firstByteMark[5] = { + 0x00, 0x00, 0xC0, 0xE0, 0xF0 + }; + // Finally, we write the bytes into ResultBuf. + ResultBuf += bytesToWrite; + switch (bytesToWrite) { // note: everything falls through. + case 4: + *--ResultBuf = (UTF8)((UcnVal | byteMark) & byteMask); UcnVal >>= 6; + LLVM_FALLTHROUGH; + case 3: + *--ResultBuf = (UTF8)((UcnVal | byteMark) & byteMask); UcnVal >>= 6; + LLVM_FALLTHROUGH; + case 2: + *--ResultBuf = (UTF8)((UcnVal | byteMark) & byteMask); UcnVal >>= 6; + LLVM_FALLTHROUGH; + case 1: + *--ResultBuf = (UTF8) (UcnVal | firstByteMark[bytesToWrite]); + } + // Update the buffer. + ResultBuf += bytesToWrite; +} + +/// integer-constant: [C99 6.4.4.1] +/// decimal-constant integer-suffix +/// octal-constant integer-suffix +/// hexadecimal-constant integer-suffix +/// binary-literal integer-suffix [GNU, C++1y] +/// user-defined-integer-literal: [C++11 lex.ext] +/// decimal-literal ud-suffix +/// octal-literal ud-suffix +/// hexadecimal-literal ud-suffix +/// binary-literal ud-suffix [GNU, C++1y] +/// decimal-constant: +/// nonzero-digit +/// decimal-constant digit +/// octal-constant: +/// 0 +/// octal-constant octal-digit +/// hexadecimal-constant: +/// hexadecimal-prefix hexadecimal-digit +/// hexadecimal-constant hexadecimal-digit +/// hexadecimal-prefix: one of +/// 0x 0X +/// binary-literal: +/// 0b binary-digit +/// 0B binary-digit +/// binary-literal binary-digit +/// integer-suffix: +/// unsigned-suffix [long-suffix] +/// unsigned-suffix [long-long-suffix] +/// long-suffix [unsigned-suffix] +/// long-long-suffix [unsigned-sufix] +/// nonzero-digit: +/// 1 2 3 4 5 6 7 8 9 +/// octal-digit: +/// 0 1 2 3 4 5 6 7 +/// hexadecimal-digit: +/// 0 1 2 3 4 5 6 7 8 9 +/// a b c d e f +/// A B C D E F +/// binary-digit: +/// 0 +/// 1 +/// unsigned-suffix: one of +/// u U +/// long-suffix: one of +/// l L +/// long-long-suffix: one of +/// ll LL +/// +/// floating-constant: [C99 6.4.4.2] +/// TODO: add rules... +/// +NumericLiteralParser::NumericLiteralParser(StringRef TokSpelling, + SourceLocation TokLoc, + Preprocessor &PP) + : PP(PP), ThisTokBegin(TokSpelling.begin()), ThisTokEnd(TokSpelling.end()) { + + // This routine assumes that the range begin/end matches the regex for integer + // and FP constants (specifically, the 'pp-number' regex), and assumes that + // the byte at "*end" is both valid and not part of the regex. Because of + // this, it doesn't have to check for 'overscan' in various places. + assert(!isPreprocessingNumberBody(*ThisTokEnd) && "didn't maximally munch?"); + + s = DigitsBegin = ThisTokBegin; + saw_exponent = false; + saw_period = false; + saw_ud_suffix = false; + saw_fixed_point_suffix = false; + isLong = false; + isUnsigned = false; + isLongLong = false; + isHalf = false; + isFloat = false; + isImaginary = false; + isFloat16 = false; + isFloat128 = false; + MicrosoftInteger = 0; + isFract = false; + isAccum = false; + hadError = false; + + if (*s == '0') { // parse radix + ParseNumberStartingWithZero(TokLoc); + if (hadError) + return; + } else { // the first digit is non-zero + radix = 10; + s = SkipDigits(s); + if (s == ThisTokEnd) { + // Done. + } else { + ParseDecimalOrOctalCommon(TokLoc); + if (hadError) + return; + } + } + + SuffixBegin = s; + checkSeparator(TokLoc, s, CSK_AfterDigits); + + // Initial scan to lookahead for fixed point suffix. + if (PP.getLangOpts().FixedPoint) { + for (const char *c = s; c != ThisTokEnd; ++c) { + if (*c == 'r' || *c == 'k' || *c == 'R' || *c == 'K') { + saw_fixed_point_suffix = true; + break; + } + } + } + + // Parse the suffix. At this point we can classify whether we have an FP or + // integer constant. + bool isFPConstant = isFloatingLiteral(); + + // Loop over all of the characters of the suffix. If we see something bad, + // we break out of the loop. + for (; s != ThisTokEnd; ++s) { + switch (*s) { + case 'R': + case 'r': + if (!PP.getLangOpts().FixedPoint) break; + if (isFract || isAccum) break; + if (!(saw_period || saw_exponent)) break; + isFract = true; + continue; + case 'K': + case 'k': + if (!PP.getLangOpts().FixedPoint) break; + if (isFract || isAccum) break; + if (!(saw_period || saw_exponent)) break; + isAccum = true; + continue; + case 'h': // FP Suffix for "half". + case 'H': + // OpenCL Extension v1.2 s9.5 - h or H suffix for half type. + if (!(PP.getLangOpts().Half || PP.getLangOpts().FixedPoint)) break; + if (isIntegerLiteral()) break; // Error for integer constant. + if (isHalf || isFloat || isLong) break; // HH, FH, LH invalid. + isHalf = true; + continue; // Success. + case 'f': // FP Suffix for "float" + case 'F': + if (!isFPConstant) break; // Error for integer constant. + if (isHalf || isFloat || isLong || isFloat128) + break; // HF, FF, LF, QF invalid. + + // CUDA host and device may have different _Float16 support, therefore + // allows f16 literals to avoid false alarm. + // ToDo: more precise check for CUDA. + if ((PP.getTargetInfo().hasFloat16Type() || PP.getLangOpts().CUDA) && + s + 2 < ThisTokEnd && s[1] == '1' && s[2] == '6') { + s += 2; // success, eat up 2 characters. + isFloat16 = true; + continue; + } + + isFloat = true; + continue; // Success. + case 'q': // FP Suffix for "__float128" + case 'Q': + if (!isFPConstant) break; // Error for integer constant. + if (isHalf || isFloat || isLong || isFloat128) + break; // HQ, FQ, LQ, QQ invalid. + isFloat128 = true; + continue; // Success. + case 'u': + case 'U': + if (isFPConstant) break; // Error for floating constant. + if (isUnsigned) break; // Cannot be repeated. + isUnsigned = true; + continue; // Success. + case 'l': + case 'L': + if (isLong || isLongLong) break; // Cannot be repeated. + if (isHalf || isFloat || isFloat128) break; // LH, LF, LQ invalid. + + // Check for long long. The L's need to be adjacent and the same case. + if (s[1] == s[0]) { + assert(s + 1 < ThisTokEnd && "didn't maximally munch?"); + if (isFPConstant) break; // long long invalid for floats. + isLongLong = true; + ++s; // Eat both of them. + } else { + isLong = true; + } + continue; // Success. + case 'i': + case 'I': + if (PP.getLangOpts().MicrosoftExt) { + if (isLong || isLongLong || MicrosoftInteger) + break; + + if (!isFPConstant) { + // Allow i8, i16, i32, and i64. + switch (s[1]) { + case '8': + s += 2; // i8 suffix + MicrosoftInteger = 8; + break; + case '1': + if (s[2] == '6') { + s += 3; // i16 suffix + MicrosoftInteger = 16; + } + break; + case '3': + if (s[2] == '2') { + s += 3; // i32 suffix + MicrosoftInteger = 32; + } + break; + case '6': + if (s[2] == '4') { + s += 3; // i64 suffix + MicrosoftInteger = 64; + } + break; + default: + break; + } + } + if (MicrosoftInteger) { + assert(s <= ThisTokEnd && "didn't maximally munch?"); + break; + } + } + LLVM_FALLTHROUGH; + case 'j': + case 'J': + if (isImaginary) break; // Cannot be repeated. + isImaginary = true; + continue; // Success. + } + // If we reached here, there was an error or a ud-suffix. + break; + } + + // "i", "if", and "il" are user-defined suffixes in C++1y. + if (s != ThisTokEnd || isImaginary) { + // FIXME: Don't bother expanding UCNs if !tok.hasUCN(). + expandUCNs(UDSuffixBuf, StringRef(SuffixBegin, ThisTokEnd - SuffixBegin)); + if (isValidUDSuffix(PP.getLangOpts(), UDSuffixBuf)) { + if (!isImaginary) { + // Any suffix pieces we might have parsed are actually part of the + // ud-suffix. + isLong = false; + isUnsigned = false; + isLongLong = false; + isFloat = false; + isFloat16 = false; + isHalf = false; + isImaginary = false; + MicrosoftInteger = 0; + saw_fixed_point_suffix = false; + isFract = false; + isAccum = false; + } + + saw_ud_suffix = true; + return; + } + + if (s != ThisTokEnd) { + // Report an error if there are any. + PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, SuffixBegin - ThisTokBegin), + diag::err_invalid_suffix_constant) + << StringRef(SuffixBegin, ThisTokEnd - SuffixBegin) << isFPConstant; + hadError = true; + } + } + + if (!hadError && saw_fixed_point_suffix) { + assert(isFract || isAccum); + } +} + +/// ParseDecimalOrOctalCommon - This method is called for decimal or octal +/// numbers. It issues an error for illegal digits, and handles floating point +/// parsing. If it detects a floating point number, the radix is set to 10. +void NumericLiteralParser::ParseDecimalOrOctalCommon(SourceLocation TokLoc){ + assert((radix == 8 || radix == 10) && "Unexpected radix"); + + // If we have a hex digit other than 'e' (which denotes a FP exponent) then + // the code is using an incorrect base. + if (isHexDigit(*s) && *s != 'e' && *s != 'E' && + !isValidUDSuffix(PP.getLangOpts(), StringRef(s, ThisTokEnd - s))) { + PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, s-ThisTokBegin), + diag::err_invalid_digit) << StringRef(s, 1) << (radix == 8 ? 1 : 0); + hadError = true; + return; + } + + if (*s == '.') { + checkSeparator(TokLoc, s, CSK_AfterDigits); + s++; + radix = 10; + saw_period = true; + checkSeparator(TokLoc, s, CSK_BeforeDigits); + s = SkipDigits(s); // Skip suffix. + } + if (*s == 'e' || *s == 'E') { // exponent + checkSeparator(TokLoc, s, CSK_AfterDigits); + const char *Exponent = s; + s++; + radix = 10; + saw_exponent = true; + if (s != ThisTokEnd && (*s == '+' || *s == '-')) s++; // sign + const char *first_non_digit = SkipDigits(s); + if (containsDigits(s, first_non_digit)) { + checkSeparator(TokLoc, s, CSK_BeforeDigits); + s = first_non_digit; + } else { + if (!hadError) { + PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, Exponent-ThisTokBegin), + diag::err_exponent_has_no_digits); + hadError = true; + } + return; + } + } +} + +/// Determine whether a suffix is a valid ud-suffix. We avoid treating reserved +/// suffixes as ud-suffixes, because the diagnostic experience is better if we +/// treat it as an invalid suffix. +bool NumericLiteralParser::isValidUDSuffix(const LangOptions &LangOpts, + StringRef Suffix) { + if (!LangOpts.CPlusPlus11 || Suffix.empty()) + return false; + + // By C++11 [lex.ext]p10, ud-suffixes starting with an '_' are always valid. + if (Suffix[0] == '_') + return true; + + // In C++11, there are no library suffixes. + if (!LangOpts.CPlusPlus14) + return false; + + // In C++14, "s", "h", "min", "ms", "us", and "ns" are used in the library. + // Per tweaked N3660, "il", "i", and "if" are also used in the library. + // In C++2a "d" and "y" are used in the library. + return llvm::StringSwitch<bool>(Suffix) + .Cases("h", "min", "s", true) + .Cases("ms", "us", "ns", true) + .Cases("il", "i", "if", true) + .Cases("d", "y", LangOpts.CPlusPlus2a) + .Default(false); +} + +void NumericLiteralParser::checkSeparator(SourceLocation TokLoc, + const char *Pos, + CheckSeparatorKind IsAfterDigits) { + if (IsAfterDigits == CSK_AfterDigits) { + if (Pos == ThisTokBegin) + return; + --Pos; + } else if (Pos == ThisTokEnd) + return; + + if (isDigitSeparator(*Pos)) { + PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, Pos - ThisTokBegin), + diag::err_digit_separator_not_between_digits) + << IsAfterDigits; + hadError = true; + } +} + +/// ParseNumberStartingWithZero - This method is called when the first character +/// of the number is found to be a zero. This means it is either an octal +/// number (like '04') or a hex number ('0x123a') a binary number ('0b1010') or +/// a floating point number (01239.123e4). Eat the prefix, determining the +/// radix etc. +void NumericLiteralParser::ParseNumberStartingWithZero(SourceLocation TokLoc) { + assert(s[0] == '0' && "Invalid method call"); + s++; + + int c1 = s[0]; + + // Handle a hex number like 0x1234. + if ((c1 == 'x' || c1 == 'X') && (isHexDigit(s[1]) || s[1] == '.')) { + s++; + assert(s < ThisTokEnd && "didn't maximally munch?"); + radix = 16; + DigitsBegin = s; + s = SkipHexDigits(s); + bool HasSignificandDigits = containsDigits(DigitsBegin, s); + if (s == ThisTokEnd) { + // Done. + } else if (*s == '.') { + s++; + saw_period = true; + const char *floatDigitsBegin = s; + s = SkipHexDigits(s); + if (containsDigits(floatDigitsBegin, s)) + HasSignificandDigits = true; + if (HasSignificandDigits) + checkSeparator(TokLoc, floatDigitsBegin, CSK_BeforeDigits); + } + + if (!HasSignificandDigits) { + PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, s - ThisTokBegin), + diag::err_hex_constant_requires) + << PP.getLangOpts().CPlusPlus << 1; + hadError = true; + return; + } + + // A binary exponent can appear with or with a '.'. If dotted, the + // binary exponent is required. + if (*s == 'p' || *s == 'P') { + checkSeparator(TokLoc, s, CSK_AfterDigits); + const char *Exponent = s; + s++; + saw_exponent = true; + if (s != ThisTokEnd && (*s == '+' || *s == '-')) s++; // sign + const char *first_non_digit = SkipDigits(s); + if (!containsDigits(s, first_non_digit)) { + if (!hadError) { + PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, Exponent-ThisTokBegin), + diag::err_exponent_has_no_digits); + hadError = true; + } + return; + } + checkSeparator(TokLoc, s, CSK_BeforeDigits); + s = first_non_digit; + + if (!PP.getLangOpts().HexFloats) + PP.Diag(TokLoc, PP.getLangOpts().CPlusPlus + ? diag::ext_hex_literal_invalid + : diag::ext_hex_constant_invalid); + else if (PP.getLangOpts().CPlusPlus17) + PP.Diag(TokLoc, diag::warn_cxx17_hex_literal); + } else if (saw_period) { + PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, s - ThisTokBegin), + diag::err_hex_constant_requires) + << PP.getLangOpts().CPlusPlus << 0; + hadError = true; + } + return; + } + + // Handle simple binary numbers 0b01010 + if ((c1 == 'b' || c1 == 'B') && (s[1] == '0' || s[1] == '1')) { + // 0b101010 is a C++1y / GCC extension. + PP.Diag(TokLoc, + PP.getLangOpts().CPlusPlus14 + ? diag::warn_cxx11_compat_binary_literal + : PP.getLangOpts().CPlusPlus + ? diag::ext_binary_literal_cxx14 + : diag::ext_binary_literal); + ++s; + assert(s < ThisTokEnd && "didn't maximally munch?"); + radix = 2; + DigitsBegin = s; + s = SkipBinaryDigits(s); + if (s == ThisTokEnd) { + // Done. + } else if (isHexDigit(*s) && + !isValidUDSuffix(PP.getLangOpts(), + StringRef(s, ThisTokEnd - s))) { + PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, s-ThisTokBegin), + diag::err_invalid_digit) << StringRef(s, 1) << 2; + hadError = true; + } + // Other suffixes will be diagnosed by the caller. + return; + } + + // For now, the radix is set to 8. If we discover that we have a + // floating point constant, the radix will change to 10. Octal floating + // point constants are not permitted (only decimal and hexadecimal). + radix = 8; + DigitsBegin = s; + s = SkipOctalDigits(s); + if (s == ThisTokEnd) + return; // Done, simple octal number like 01234 + + // If we have some other non-octal digit that *is* a decimal digit, see if + // this is part of a floating point number like 094.123 or 09e1. + if (isDigit(*s)) { + const char *EndDecimal = SkipDigits(s); + if (EndDecimal[0] == '.' || EndDecimal[0] == 'e' || EndDecimal[0] == 'E') { + s = EndDecimal; + radix = 10; + } + } + + ParseDecimalOrOctalCommon(TokLoc); +} + +static bool alwaysFitsInto64Bits(unsigned Radix, unsigned NumDigits) { + switch (Radix) { + case 2: + return NumDigits <= 64; + case 8: + return NumDigits <= 64 / 3; // Digits are groups of 3 bits. + case 10: + return NumDigits <= 19; // floor(log10(2^64)) + case 16: + return NumDigits <= 64 / 4; // Digits are groups of 4 bits. + default: + llvm_unreachable("impossible Radix"); + } +} + +/// GetIntegerValue - Convert this numeric literal value to an APInt that +/// matches Val's input width. If there is an overflow, set Val to the low bits +/// of the result and return true. Otherwise, return false. +bool NumericLiteralParser::GetIntegerValue(llvm::APInt &Val) { + // Fast path: Compute a conservative bound on the maximum number of + // bits per digit in this radix. If we can't possibly overflow a + // uint64 based on that bound then do the simple conversion to + // integer. This avoids the expensive overflow checking below, and + // handles the common cases that matter (small decimal integers and + // hex/octal values which don't overflow). + const unsigned NumDigits = SuffixBegin - DigitsBegin; + if (alwaysFitsInto64Bits(radix, NumDigits)) { + uint64_t N = 0; + for (const char *Ptr = DigitsBegin; Ptr != SuffixBegin; ++Ptr) + if (!isDigitSeparator(*Ptr)) + N = N * radix + llvm::hexDigitValue(*Ptr); + + // This will truncate the value to Val's input width. Simply check + // for overflow by comparing. + Val = N; + return Val.getZExtValue() != N; + } + + Val = 0; + const char *Ptr = DigitsBegin; + + llvm::APInt RadixVal(Val.getBitWidth(), radix); + llvm::APInt CharVal(Val.getBitWidth(), 0); + llvm::APInt OldVal = Val; + + bool OverflowOccurred = false; + while (Ptr < SuffixBegin) { + if (isDigitSeparator(*Ptr)) { + ++Ptr; + continue; + } + + unsigned C = llvm::hexDigitValue(*Ptr++); + + // If this letter is out of bound for this radix, reject it. + assert(C < radix && "NumericLiteralParser ctor should have rejected this"); + + CharVal = C; + + // Add the digit to the value in the appropriate radix. If adding in digits + // made the value smaller, then this overflowed. + OldVal = Val; + + // Multiply by radix, did overflow occur on the multiply? + Val *= RadixVal; + OverflowOccurred |= Val.udiv(RadixVal) != OldVal; + + // Add value, did overflow occur on the value? + // (a + b) ult b <=> overflow + Val += CharVal; + OverflowOccurred |= Val.ult(CharVal); + } + return OverflowOccurred; +} + +llvm::APFloat::opStatus +NumericLiteralParser::GetFloatValue(llvm::APFloat &Result) { + using llvm::APFloat; + + unsigned n = std::min(SuffixBegin - ThisTokBegin, ThisTokEnd - ThisTokBegin); + + llvm::SmallString<16> Buffer; + StringRef Str(ThisTokBegin, n); + if (Str.find('\'') != StringRef::npos) { + Buffer.reserve(n); + std::remove_copy_if(Str.begin(), Str.end(), std::back_inserter(Buffer), + &isDigitSeparator); + Str = Buffer; + } + + return Result.convertFromString(Str, APFloat::rmNearestTiesToEven); +} + +static inline bool IsExponentPart(char c) { + return c == 'p' || c == 'P' || c == 'e' || c == 'E'; +} + +bool NumericLiteralParser::GetFixedPointValue(llvm::APInt &StoreVal, unsigned Scale) { + assert(radix == 16 || radix == 10); + + // Find how many digits are needed to store the whole literal. + unsigned NumDigits = SuffixBegin - DigitsBegin; + if (saw_period) --NumDigits; + + // Initial scan of the exponent if it exists + bool ExpOverflowOccurred = false; + bool NegativeExponent = false; + const char *ExponentBegin; + uint64_t Exponent = 0; + int64_t BaseShift = 0; + if (saw_exponent) { + const char *Ptr = DigitsBegin; + + while (!IsExponentPart(*Ptr)) ++Ptr; + ExponentBegin = Ptr; + ++Ptr; + NegativeExponent = *Ptr == '-'; + if (NegativeExponent) ++Ptr; + + unsigned NumExpDigits = SuffixBegin - Ptr; + if (alwaysFitsInto64Bits(radix, NumExpDigits)) { + llvm::StringRef ExpStr(Ptr, NumExpDigits); + llvm::APInt ExpInt(/*numBits=*/64, ExpStr, /*radix=*/10); + Exponent = ExpInt.getZExtValue(); + } else { + ExpOverflowOccurred = true; + } + + if (NegativeExponent) BaseShift -= Exponent; + else BaseShift += Exponent; + } + + // Number of bits needed for decimal literal is + // ceil(NumDigits * log2(10)) Integral part + // + Scale Fractional part + // + ceil(Exponent * log2(10)) Exponent + // -------------------------------------------------- + // ceil((NumDigits + Exponent) * log2(10)) + Scale + // + // But for simplicity in handling integers, we can round up log2(10) to 4, + // making: + // 4 * (NumDigits + Exponent) + Scale + // + // Number of digits needed for hexadecimal literal is + // 4 * NumDigits Integral part + // + Scale Fractional part + // + Exponent Exponent + // -------------------------------------------------- + // (4 * NumDigits) + Scale + Exponent + uint64_t NumBitsNeeded; + if (radix == 10) + NumBitsNeeded = 4 * (NumDigits + Exponent) + Scale; + else + NumBitsNeeded = 4 * NumDigits + Exponent + Scale; + + if (NumBitsNeeded > std::numeric_limits<unsigned>::max()) + ExpOverflowOccurred = true; + llvm::APInt Val(static_cast<unsigned>(NumBitsNeeded), 0, /*isSigned=*/false); + + bool FoundDecimal = false; + + int64_t FractBaseShift = 0; + const char *End = saw_exponent ? ExponentBegin : SuffixBegin; + for (const char *Ptr = DigitsBegin; Ptr < End; ++Ptr) { + if (*Ptr == '.') { + FoundDecimal = true; + continue; + } + + // Normal reading of an integer + unsigned C = llvm::hexDigitValue(*Ptr); + assert(C < radix && "NumericLiteralParser ctor should have rejected this"); + + Val *= radix; + Val += C; + + if (FoundDecimal) + // Keep track of how much we will need to adjust this value by from the + // number of digits past the radix point. + --FractBaseShift; + } + + // For a radix of 16, we will be multiplying by 2 instead of 16. + if (radix == 16) FractBaseShift *= 4; + BaseShift += FractBaseShift; + + Val <<= Scale; + + uint64_t Base = (radix == 16) ? 2 : 10; + if (BaseShift > 0) { + for (int64_t i = 0; i < BaseShift; ++i) { + Val *= Base; + } + } else if (BaseShift < 0) { + for (int64_t i = BaseShift; i < 0 && !Val.isNullValue(); ++i) + Val = Val.udiv(Base); + } + + bool IntOverflowOccurred = false; + auto MaxVal = llvm::APInt::getMaxValue(StoreVal.getBitWidth()); + if (Val.getBitWidth() > StoreVal.getBitWidth()) { + IntOverflowOccurred |= Val.ugt(MaxVal.zext(Val.getBitWidth())); + StoreVal = Val.trunc(StoreVal.getBitWidth()); + } else if (Val.getBitWidth() < StoreVal.getBitWidth()) { + IntOverflowOccurred |= Val.zext(MaxVal.getBitWidth()).ugt(MaxVal); + StoreVal = Val.zext(StoreVal.getBitWidth()); + } else { + StoreVal = Val; + } + + return IntOverflowOccurred || ExpOverflowOccurred; +} + +/// \verbatim +/// user-defined-character-literal: [C++11 lex.ext] +/// character-literal ud-suffix +/// ud-suffix: +/// identifier +/// character-literal: [C++11 lex.ccon] +/// ' c-char-sequence ' +/// u' c-char-sequence ' +/// U' c-char-sequence ' +/// L' c-char-sequence ' +/// u8' c-char-sequence ' [C++1z lex.ccon] +/// c-char-sequence: +/// c-char +/// c-char-sequence c-char +/// c-char: +/// any member of the source character set except the single-quote ', +/// backslash \, or new-line character +/// escape-sequence +/// universal-character-name +/// escape-sequence: +/// simple-escape-sequence +/// octal-escape-sequence +/// hexadecimal-escape-sequence +/// simple-escape-sequence: +/// one of \' \" \? \\ \a \b \f \n \r \t \v +/// octal-escape-sequence: +/// \ octal-digit +/// \ octal-digit octal-digit +/// \ octal-digit octal-digit octal-digit +/// hexadecimal-escape-sequence: +/// \x hexadecimal-digit +/// hexadecimal-escape-sequence hexadecimal-digit +/// universal-character-name: [C++11 lex.charset] +/// \u hex-quad +/// \U hex-quad hex-quad +/// hex-quad: +/// hex-digit hex-digit hex-digit hex-digit +/// \endverbatim +/// +CharLiteralParser::CharLiteralParser(const char *begin, const char *end, + SourceLocation Loc, Preprocessor &PP, + tok::TokenKind kind) { + // At this point we know that the character matches the regex "(L|u|U)?'.*'". + HadError = false; + + Kind = kind; + + const char *TokBegin = begin; + + // Skip over wide character determinant. + if (Kind != tok::char_constant) + ++begin; + if (Kind == tok::utf8_char_constant) + ++begin; + + // Skip over the entry quote. + assert(begin[0] == '\'' && "Invalid token lexed"); + ++begin; + + // Remove an optional ud-suffix. + if (end[-1] != '\'') { + const char *UDSuffixEnd = end; + do { + --end; + } while (end[-1] != '\''); + // FIXME: Don't bother with this if !tok.hasUCN(). + expandUCNs(UDSuffixBuf, StringRef(end, UDSuffixEnd - end)); + UDSuffixOffset = end - TokBegin; + } + + // Trim the ending quote. + assert(end != begin && "Invalid token lexed"); + --end; + + // FIXME: The "Value" is an uint64_t so we can handle char literals of + // up to 64-bits. + // FIXME: This extensively assumes that 'char' is 8-bits. + assert(PP.getTargetInfo().getCharWidth() == 8 && + "Assumes char is 8 bits"); + assert(PP.getTargetInfo().getIntWidth() <= 64 && + (PP.getTargetInfo().getIntWidth() & 7) == 0 && + "Assumes sizeof(int) on target is <= 64 and a multiple of char"); + assert(PP.getTargetInfo().getWCharWidth() <= 64 && + "Assumes sizeof(wchar) on target is <= 64"); + + SmallVector<uint32_t, 4> codepoint_buffer; + codepoint_buffer.resize(end - begin); + uint32_t *buffer_begin = &codepoint_buffer.front(); + uint32_t *buffer_end = buffer_begin + codepoint_buffer.size(); + + // Unicode escapes representing characters that cannot be correctly + // represented in a single code unit are disallowed in character literals + // by this implementation. + uint32_t largest_character_for_kind; + if (tok::wide_char_constant == Kind) { + largest_character_for_kind = + 0xFFFFFFFFu >> (32-PP.getTargetInfo().getWCharWidth()); + } else if (tok::utf8_char_constant == Kind) { + largest_character_for_kind = 0x7F; + } else if (tok::utf16_char_constant == Kind) { + largest_character_for_kind = 0xFFFF; + } else if (tok::utf32_char_constant == Kind) { + largest_character_for_kind = 0x10FFFF; + } else { + largest_character_for_kind = 0x7Fu; + } + + while (begin != end) { + // Is this a span of non-escape characters? + if (begin[0] != '\\') { + char const *start = begin; + do { + ++begin; + } while (begin != end && *begin != '\\'); + + char const *tmp_in_start = start; + uint32_t *tmp_out_start = buffer_begin; + llvm::ConversionResult res = + llvm::ConvertUTF8toUTF32(reinterpret_cast<llvm::UTF8 const **>(&start), + reinterpret_cast<llvm::UTF8 const *>(begin), + &buffer_begin, buffer_end, llvm::strictConversion); + if (res != llvm::conversionOK) { + // If we see bad encoding for unprefixed character literals, warn and + // simply copy the byte values, for compatibility with gcc and + // older versions of clang. + bool NoErrorOnBadEncoding = isAscii(); + unsigned Msg = diag::err_bad_character_encoding; + if (NoErrorOnBadEncoding) + Msg = diag::warn_bad_character_encoding; + PP.Diag(Loc, Msg); + if (NoErrorOnBadEncoding) { + start = tmp_in_start; + buffer_begin = tmp_out_start; + for (; start != begin; ++start, ++buffer_begin) + *buffer_begin = static_cast<uint8_t>(*start); + } else { + HadError = true; + } + } else { + for (; tmp_out_start < buffer_begin; ++tmp_out_start) { + if (*tmp_out_start > largest_character_for_kind) { + HadError = true; + PP.Diag(Loc, diag::err_character_too_large); + } + } + } + + continue; + } + // Is this a Universal Character Name escape? + if (begin[1] == 'u' || begin[1] == 'U') { + unsigned short UcnLen = 0; + if (!ProcessUCNEscape(TokBegin, begin, end, *buffer_begin, UcnLen, + FullSourceLoc(Loc, PP.getSourceManager()), + &PP.getDiagnostics(), PP.getLangOpts(), true)) { + HadError = true; + } else if (*buffer_begin > largest_character_for_kind) { + HadError = true; + PP.Diag(Loc, diag::err_character_too_large); + } + + ++buffer_begin; + continue; + } + unsigned CharWidth = getCharWidth(Kind, PP.getTargetInfo()); + uint64_t result = + ProcessCharEscape(TokBegin, begin, end, HadError, + FullSourceLoc(Loc,PP.getSourceManager()), + CharWidth, &PP.getDiagnostics(), PP.getLangOpts()); + *buffer_begin++ = result; + } + + unsigned NumCharsSoFar = buffer_begin - &codepoint_buffer.front(); + + if (NumCharsSoFar > 1) { + if (isWide()) + PP.Diag(Loc, diag::warn_extraneous_char_constant); + else if (isAscii() && NumCharsSoFar == 4) + PP.Diag(Loc, diag::ext_four_char_character_literal); + else if (isAscii()) + PP.Diag(Loc, diag::ext_multichar_character_literal); + else + PP.Diag(Loc, diag::err_multichar_utf_character_literal); + IsMultiChar = true; + } else { + IsMultiChar = false; + } + + llvm::APInt LitVal(PP.getTargetInfo().getIntWidth(), 0); + + // Narrow character literals act as though their value is concatenated + // in this implementation, but warn on overflow. + bool multi_char_too_long = false; + if (isAscii() && isMultiChar()) { + LitVal = 0; + for (size_t i = 0; i < NumCharsSoFar; ++i) { + // check for enough leading zeros to shift into + multi_char_too_long |= (LitVal.countLeadingZeros() < 8); + LitVal <<= 8; + LitVal = LitVal + (codepoint_buffer[i] & 0xFF); + } + } else if (NumCharsSoFar > 0) { + // otherwise just take the last character + LitVal = buffer_begin[-1]; + } + + if (!HadError && multi_char_too_long) { + PP.Diag(Loc, diag::warn_char_constant_too_large); + } + + // Transfer the value from APInt to uint64_t + Value = LitVal.getZExtValue(); + + // If this is a single narrow character, sign extend it (e.g. '\xFF' is "-1") + // if 'char' is signed for this target (C99 6.4.4.4p10). Note that multiple + // character constants are not sign extended in the this implementation: + // '\xFF\xFF' = 65536 and '\x0\xFF' = 255, which matches GCC. + if (isAscii() && NumCharsSoFar == 1 && (Value & 128) && + PP.getLangOpts().CharIsSigned) + Value = (signed char)Value; +} + +/// \verbatim +/// string-literal: [C++0x lex.string] +/// encoding-prefix " [s-char-sequence] " +/// encoding-prefix R raw-string +/// encoding-prefix: +/// u8 +/// u +/// U +/// L +/// s-char-sequence: +/// s-char +/// s-char-sequence s-char +/// s-char: +/// any member of the source character set except the double-quote ", +/// backslash \, or new-line character +/// escape-sequence +/// universal-character-name +/// raw-string: +/// " d-char-sequence ( r-char-sequence ) d-char-sequence " +/// r-char-sequence: +/// r-char +/// r-char-sequence r-char +/// r-char: +/// any member of the source character set, except a right parenthesis ) +/// followed by the initial d-char-sequence (which may be empty) +/// followed by a double quote ". +/// d-char-sequence: +/// d-char +/// d-char-sequence d-char +/// d-char: +/// any member of the basic source character set except: +/// space, the left parenthesis (, the right parenthesis ), +/// the backslash \, and the control characters representing horizontal +/// tab, vertical tab, form feed, and newline. +/// escape-sequence: [C++0x lex.ccon] +/// simple-escape-sequence +/// octal-escape-sequence +/// hexadecimal-escape-sequence +/// simple-escape-sequence: +/// one of \' \" \? \\ \a \b \f \n \r \t \v +/// octal-escape-sequence: +/// \ octal-digit +/// \ octal-digit octal-digit +/// \ octal-digit octal-digit octal-digit +/// hexadecimal-escape-sequence: +/// \x hexadecimal-digit +/// hexadecimal-escape-sequence hexadecimal-digit +/// universal-character-name: +/// \u hex-quad +/// \U hex-quad hex-quad +/// hex-quad: +/// hex-digit hex-digit hex-digit hex-digit +/// \endverbatim +/// +StringLiteralParser:: +StringLiteralParser(ArrayRef<Token> StringToks, + Preprocessor &PP, bool Complain) + : SM(PP.getSourceManager()), Features(PP.getLangOpts()), + Target(PP.getTargetInfo()), Diags(Complain ? &PP.getDiagnostics() :nullptr), + MaxTokenLength(0), SizeBound(0), CharByteWidth(0), Kind(tok::unknown), + ResultPtr(ResultBuf.data()), hadError(false), Pascal(false) { + init(StringToks); +} + +void StringLiteralParser::init(ArrayRef<Token> StringToks){ + // The literal token may have come from an invalid source location (e.g. due + // to a PCH error), in which case the token length will be 0. + if (StringToks.empty() || StringToks[0].getLength() < 2) + return DiagnoseLexingError(SourceLocation()); + + // Scan all of the string portions, remember the max individual token length, + // computing a bound on the concatenated string length, and see whether any + // piece is a wide-string. If any of the string portions is a wide-string + // literal, the result is a wide-string literal [C99 6.4.5p4]. + assert(!StringToks.empty() && "expected at least one token"); + MaxTokenLength = StringToks[0].getLength(); + assert(StringToks[0].getLength() >= 2 && "literal token is invalid!"); + SizeBound = StringToks[0].getLength()-2; // -2 for "". + Kind = StringToks[0].getKind(); + + hadError = false; + + // Implement Translation Phase #6: concatenation of string literals + /// (C99 5.1.1.2p1). The common case is only one string fragment. + for (unsigned i = 1; i != StringToks.size(); ++i) { + if (StringToks[i].getLength() < 2) + return DiagnoseLexingError(StringToks[i].getLocation()); + + // The string could be shorter than this if it needs cleaning, but this is a + // reasonable bound, which is all we need. + assert(StringToks[i].getLength() >= 2 && "literal token is invalid!"); + SizeBound += StringToks[i].getLength()-2; // -2 for "". + + // Remember maximum string piece length. + if (StringToks[i].getLength() > MaxTokenLength) + MaxTokenLength = StringToks[i].getLength(); + + // Remember if we see any wide or utf-8/16/32 strings. + // Also check for illegal concatenations. + if (StringToks[i].isNot(Kind) && StringToks[i].isNot(tok::string_literal)) { + if (isAscii()) { + Kind = StringToks[i].getKind(); + } else { + if (Diags) + Diags->Report(StringToks[i].getLocation(), + diag::err_unsupported_string_concat); + hadError = true; + } + } + } + + // Include space for the null terminator. + ++SizeBound; + + // TODO: K&R warning: "traditional C rejects string constant concatenation" + + // Get the width in bytes of char/wchar_t/char16_t/char32_t + CharByteWidth = getCharWidth(Kind, Target); + assert((CharByteWidth & 7) == 0 && "Assumes character size is byte multiple"); + CharByteWidth /= 8; + + // The output buffer size needs to be large enough to hold wide characters. + // This is a worst-case assumption which basically corresponds to L"" "long". + SizeBound *= CharByteWidth; + + // Size the temporary buffer to hold the result string data. + ResultBuf.resize(SizeBound); + + // Likewise, but for each string piece. + SmallString<512> TokenBuf; + TokenBuf.resize(MaxTokenLength); + + // Loop over all the strings, getting their spelling, and expanding them to + // wide strings as appropriate. + ResultPtr = &ResultBuf[0]; // Next byte to fill in. + + Pascal = false; + + SourceLocation UDSuffixTokLoc; + + for (unsigned i = 0, e = StringToks.size(); i != e; ++i) { + const char *ThisTokBuf = &TokenBuf[0]; + // Get the spelling of the token, which eliminates trigraphs, etc. We know + // that ThisTokBuf points to a buffer that is big enough for the whole token + // and 'spelled' tokens can only shrink. + bool StringInvalid = false; + unsigned ThisTokLen = + Lexer::getSpelling(StringToks[i], ThisTokBuf, SM, Features, + &StringInvalid); + if (StringInvalid) + return DiagnoseLexingError(StringToks[i].getLocation()); + + const char *ThisTokBegin = ThisTokBuf; + const char *ThisTokEnd = ThisTokBuf+ThisTokLen; + + // Remove an optional ud-suffix. + if (ThisTokEnd[-1] != '"') { + const char *UDSuffixEnd = ThisTokEnd; + do { + --ThisTokEnd; + } while (ThisTokEnd[-1] != '"'); + + StringRef UDSuffix(ThisTokEnd, UDSuffixEnd - ThisTokEnd); + + if (UDSuffixBuf.empty()) { + if (StringToks[i].hasUCN()) + expandUCNs(UDSuffixBuf, UDSuffix); + else + UDSuffixBuf.assign(UDSuffix); + UDSuffixToken = i; + UDSuffixOffset = ThisTokEnd - ThisTokBuf; + UDSuffixTokLoc = StringToks[i].getLocation(); + } else { + SmallString<32> ExpandedUDSuffix; + if (StringToks[i].hasUCN()) { + expandUCNs(ExpandedUDSuffix, UDSuffix); + UDSuffix = ExpandedUDSuffix; + } + + // C++11 [lex.ext]p8: At the end of phase 6, if a string literal is the + // result of a concatenation involving at least one user-defined-string- + // literal, all the participating user-defined-string-literals shall + // have the same ud-suffix. + if (UDSuffixBuf != UDSuffix) { + if (Diags) { + SourceLocation TokLoc = StringToks[i].getLocation(); + Diags->Report(TokLoc, diag::err_string_concat_mixed_suffix) + << UDSuffixBuf << UDSuffix + << SourceRange(UDSuffixTokLoc, UDSuffixTokLoc) + << SourceRange(TokLoc, TokLoc); + } + hadError = true; + } + } + } + + // Strip the end quote. + --ThisTokEnd; + + // TODO: Input character set mapping support. + + // Skip marker for wide or unicode strings. + if (ThisTokBuf[0] == 'L' || ThisTokBuf[0] == 'u' || ThisTokBuf[0] == 'U') { + ++ThisTokBuf; + // Skip 8 of u8 marker for utf8 strings. + if (ThisTokBuf[0] == '8') + ++ThisTokBuf; + } + + // Check for raw string + if (ThisTokBuf[0] == 'R') { + ThisTokBuf += 2; // skip R" + + const char *Prefix = ThisTokBuf; + while (ThisTokBuf[0] != '(') + ++ThisTokBuf; + ++ThisTokBuf; // skip '(' + + // Remove same number of characters from the end + ThisTokEnd -= ThisTokBuf - Prefix; + assert(ThisTokEnd >= ThisTokBuf && "malformed raw string literal"); + + // C++14 [lex.string]p4: A source-file new-line in a raw string literal + // results in a new-line in the resulting execution string-literal. + StringRef RemainingTokenSpan(ThisTokBuf, ThisTokEnd - ThisTokBuf); + while (!RemainingTokenSpan.empty()) { + // Split the string literal on \r\n boundaries. + size_t CRLFPos = RemainingTokenSpan.find("\r\n"); + StringRef BeforeCRLF = RemainingTokenSpan.substr(0, CRLFPos); + StringRef AfterCRLF = RemainingTokenSpan.substr(CRLFPos); + + // Copy everything before the \r\n sequence into the string literal. + if (CopyStringFragment(StringToks[i], ThisTokBegin, BeforeCRLF)) + hadError = true; + + // Point into the \n inside the \r\n sequence and operate on the + // remaining portion of the literal. + RemainingTokenSpan = AfterCRLF.substr(1); + } + } else { + if (ThisTokBuf[0] != '"') { + // The file may have come from PCH and then changed after loading the + // PCH; Fail gracefully. + return DiagnoseLexingError(StringToks[i].getLocation()); + } + ++ThisTokBuf; // skip " + + // Check if this is a pascal string + if (Features.PascalStrings && ThisTokBuf + 1 != ThisTokEnd && + ThisTokBuf[0] == '\\' && ThisTokBuf[1] == 'p') { + + // If the \p sequence is found in the first token, we have a pascal string + // Otherwise, if we already have a pascal string, ignore the first \p + if (i == 0) { + ++ThisTokBuf; + Pascal = true; + } else if (Pascal) + ThisTokBuf += 2; + } + + while (ThisTokBuf != ThisTokEnd) { + // Is this a span of non-escape characters? + if (ThisTokBuf[0] != '\\') { + const char *InStart = ThisTokBuf; + do { + ++ThisTokBuf; + } while (ThisTokBuf != ThisTokEnd && ThisTokBuf[0] != '\\'); + + // Copy the character span over. + if (CopyStringFragment(StringToks[i], ThisTokBegin, + StringRef(InStart, ThisTokBuf - InStart))) + hadError = true; + continue; + } + // Is this a Universal Character Name escape? + if (ThisTokBuf[1] == 'u' || ThisTokBuf[1] == 'U') { + EncodeUCNEscape(ThisTokBegin, ThisTokBuf, ThisTokEnd, + ResultPtr, hadError, + FullSourceLoc(StringToks[i].getLocation(), SM), + CharByteWidth, Diags, Features); + continue; + } + // Otherwise, this is a non-UCN escape character. Process it. + unsigned ResultChar = + ProcessCharEscape(ThisTokBegin, ThisTokBuf, ThisTokEnd, hadError, + FullSourceLoc(StringToks[i].getLocation(), SM), + CharByteWidth*8, Diags, Features); + + if (CharByteWidth == 4) { + // FIXME: Make the type of the result buffer correct instead of + // using reinterpret_cast. + llvm::UTF32 *ResultWidePtr = reinterpret_cast<llvm::UTF32*>(ResultPtr); + *ResultWidePtr = ResultChar; + ResultPtr += 4; + } else if (CharByteWidth == 2) { + // FIXME: Make the type of the result buffer correct instead of + // using reinterpret_cast. + llvm::UTF16 *ResultWidePtr = reinterpret_cast<llvm::UTF16*>(ResultPtr); + *ResultWidePtr = ResultChar & 0xFFFF; + ResultPtr += 2; + } else { + assert(CharByteWidth == 1 && "Unexpected char width"); + *ResultPtr++ = ResultChar & 0xFF; + } + } + } + } + + if (Pascal) { + if (CharByteWidth == 4) { + // FIXME: Make the type of the result buffer correct instead of + // using reinterpret_cast. + llvm::UTF32 *ResultWidePtr = reinterpret_cast<llvm::UTF32*>(ResultBuf.data()); + ResultWidePtr[0] = GetNumStringChars() - 1; + } else if (CharByteWidth == 2) { + // FIXME: Make the type of the result buffer correct instead of + // using reinterpret_cast. + llvm::UTF16 *ResultWidePtr = reinterpret_cast<llvm::UTF16*>(ResultBuf.data()); + ResultWidePtr[0] = GetNumStringChars() - 1; + } else { + assert(CharByteWidth == 1 && "Unexpected char width"); + ResultBuf[0] = GetNumStringChars() - 1; + } + + // Verify that pascal strings aren't too large. + if (GetStringLength() > 256) { + if (Diags) + Diags->Report(StringToks.front().getLocation(), + diag::err_pascal_string_too_long) + << SourceRange(StringToks.front().getLocation(), + StringToks.back().getLocation()); + hadError = true; + return; + } + } else if (Diags) { + // Complain if this string literal has too many characters. + unsigned MaxChars = Features.CPlusPlus? 65536 : Features.C99 ? 4095 : 509; + + if (GetNumStringChars() > MaxChars) + Diags->Report(StringToks.front().getLocation(), + diag::ext_string_too_long) + << GetNumStringChars() << MaxChars + << (Features.CPlusPlus ? 2 : Features.C99 ? 1 : 0) + << SourceRange(StringToks.front().getLocation(), + StringToks.back().getLocation()); + } +} + +static const char *resyncUTF8(const char *Err, const char *End) { + if (Err == End) + return End; + End = Err + std::min<unsigned>(llvm::getNumBytesForUTF8(*Err), End-Err); + while (++Err != End && (*Err & 0xC0) == 0x80) + ; + return Err; +} + +/// This function copies from Fragment, which is a sequence of bytes +/// within Tok's contents (which begin at TokBegin) into ResultPtr. +/// Performs widening for multi-byte characters. +bool StringLiteralParser::CopyStringFragment(const Token &Tok, + const char *TokBegin, + StringRef Fragment) { + const llvm::UTF8 *ErrorPtrTmp; + if (ConvertUTF8toWide(CharByteWidth, Fragment, ResultPtr, ErrorPtrTmp)) + return false; + + // If we see bad encoding for unprefixed string literals, warn and + // simply copy the byte values, for compatibility with gcc and older + // versions of clang. + bool NoErrorOnBadEncoding = isAscii(); + if (NoErrorOnBadEncoding) { + memcpy(ResultPtr, Fragment.data(), Fragment.size()); + ResultPtr += Fragment.size(); + } + + if (Diags) { + const char *ErrorPtr = reinterpret_cast<const char *>(ErrorPtrTmp); + + FullSourceLoc SourceLoc(Tok.getLocation(), SM); + const DiagnosticBuilder &Builder = + Diag(Diags, Features, SourceLoc, TokBegin, + ErrorPtr, resyncUTF8(ErrorPtr, Fragment.end()), + NoErrorOnBadEncoding ? diag::warn_bad_string_encoding + : diag::err_bad_string_encoding); + + const char *NextStart = resyncUTF8(ErrorPtr, Fragment.end()); + StringRef NextFragment(NextStart, Fragment.end()-NextStart); + + // Decode into a dummy buffer. + SmallString<512> Dummy; + Dummy.reserve(Fragment.size() * CharByteWidth); + char *Ptr = Dummy.data(); + + while (!ConvertUTF8toWide(CharByteWidth, NextFragment, Ptr, ErrorPtrTmp)) { + const char *ErrorPtr = reinterpret_cast<const char *>(ErrorPtrTmp); + NextStart = resyncUTF8(ErrorPtr, Fragment.end()); + Builder << MakeCharSourceRange(Features, SourceLoc, TokBegin, + ErrorPtr, NextStart); + NextFragment = StringRef(NextStart, Fragment.end()-NextStart); + } + } + return !NoErrorOnBadEncoding; +} + +void StringLiteralParser::DiagnoseLexingError(SourceLocation Loc) { + hadError = true; + if (Diags) + Diags->Report(Loc, diag::err_lexing_string); +} + +/// getOffsetOfStringByte - This function returns the offset of the +/// specified byte of the string data represented by Token. This handles +/// advancing over escape sequences in the string. +unsigned StringLiteralParser::getOffsetOfStringByte(const Token &Tok, + unsigned ByteNo) const { + // Get the spelling of the token. + SmallString<32> SpellingBuffer; + SpellingBuffer.resize(Tok.getLength()); + + bool StringInvalid = false; + const char *SpellingPtr = &SpellingBuffer[0]; + unsigned TokLen = Lexer::getSpelling(Tok, SpellingPtr, SM, Features, + &StringInvalid); + if (StringInvalid) + return 0; + + const char *SpellingStart = SpellingPtr; + const char *SpellingEnd = SpellingPtr+TokLen; + + // Handle UTF-8 strings just like narrow strings. + if (SpellingPtr[0] == 'u' && SpellingPtr[1] == '8') + SpellingPtr += 2; + + assert(SpellingPtr[0] != 'L' && SpellingPtr[0] != 'u' && + SpellingPtr[0] != 'U' && "Doesn't handle wide or utf strings yet"); + + // For raw string literals, this is easy. + if (SpellingPtr[0] == 'R') { + assert(SpellingPtr[1] == '"' && "Should be a raw string literal!"); + // Skip 'R"'. + SpellingPtr += 2; + while (*SpellingPtr != '(') { + ++SpellingPtr; + assert(SpellingPtr < SpellingEnd && "Missing ( for raw string literal"); + } + // Skip '('. + ++SpellingPtr; + return SpellingPtr - SpellingStart + ByteNo; + } + + // Skip over the leading quote + assert(SpellingPtr[0] == '"' && "Should be a string literal!"); + ++SpellingPtr; + + // Skip over bytes until we find the offset we're looking for. + while (ByteNo) { + assert(SpellingPtr < SpellingEnd && "Didn't find byte offset!"); + + // Step over non-escapes simply. + if (*SpellingPtr != '\\') { + ++SpellingPtr; + --ByteNo; + continue; + } + + // Otherwise, this is an escape character. Advance over it. + bool HadError = false; + if (SpellingPtr[1] == 'u' || SpellingPtr[1] == 'U') { + const char *EscapePtr = SpellingPtr; + unsigned Len = MeasureUCNEscape(SpellingStart, SpellingPtr, SpellingEnd, + 1, Features, HadError); + if (Len > ByteNo) { + // ByteNo is somewhere within the escape sequence. + SpellingPtr = EscapePtr; + break; + } + ByteNo -= Len; + } else { + ProcessCharEscape(SpellingStart, SpellingPtr, SpellingEnd, HadError, + FullSourceLoc(Tok.getLocation(), SM), + CharByteWidth*8, Diags, Features); + --ByteNo; + } + assert(!HadError && "This method isn't valid on erroneous strings"); + } + + return SpellingPtr-SpellingStart; +} + +/// Determine whether a suffix is a valid ud-suffix. We avoid treating reserved +/// suffixes as ud-suffixes, because the diagnostic experience is better if we +/// treat it as an invalid suffix. +bool StringLiteralParser::isValidUDSuffix(const LangOptions &LangOpts, + StringRef Suffix) { + return NumericLiteralParser::isValidUDSuffix(LangOpts, Suffix) || + Suffix == "sv"; +} |