Example #1
0
/// EvaluateDefined - Process a 'defined(sym)' expression.
static bool EvaluateDefined(PPValue &Result, Token &PeekTok, DefinedTracker &DT,
                            bool ValueLive, Preprocessor &PP) {
  IdentifierInfo *II;
  Result.setBegin(PeekTok.getLocation());

  // Get the next token, don't expand it.
  PP.LexUnexpandedNonComment(PeekTok);

  // Two options, it can either be a pp-identifier or a (.
  SourceLocation LParenLoc;
  if (PeekTok.is(tok::l_paren)) {
    // Found a paren, remember we saw it and skip it.
    LParenLoc = PeekTok.getLocation();
    PP.LexUnexpandedNonComment(PeekTok);
  }

  if (PeekTok.is(tok::code_completion)) {
    if (PP.getCodeCompletionHandler())
      PP.getCodeCompletionHandler()->CodeCompleteMacroName(false);
    PP.setCodeCompletionReached();
    PP.LexUnexpandedNonComment(PeekTok);
  }
  
  // If we don't have a pp-identifier now, this is an error.
  if ((II = PeekTok.getIdentifierInfo()) == 0) {
    PP.Diag(PeekTok, diag::err_pp_defined_requires_identifier);
    return true;
  }

  // Otherwise, we got an identifier, is it defined to something?
  Result.Val = II->hasMacroDefinition();
  Result.Val.setIsUnsigned(false);  // Result is signed intmax_t.

  MacroInfo *Macro = 0;
  // If there is a macro, mark it used.
  if (Result.Val != 0 && ValueLive) {
    Macro = PP.getMacroInfo(II);
    PP.markMacroAsUsed(Macro);
  }

  // Invoke the 'defined' callback.
  if (PPCallbacks *Callbacks = PP.getPPCallbacks()) {
    MacroInfo *MI = Macro;
    // Pass the MacroInfo for the macro name even if the value is dead.
    if (!MI && Result.Val != 0)
      MI = PP.getMacroInfo(II);
    Callbacks->Defined(PeekTok, MI);
  }

  // If we are in parens, ensure we have a trailing ).
  if (LParenLoc.isValid()) {
    // Consume identifier.
    Result.setEnd(PeekTok.getLocation());
    PP.LexUnexpandedNonComment(PeekTok);

    if (PeekTok.isNot(tok::r_paren)) {
      PP.Diag(PeekTok.getLocation(), diag::err_pp_missing_rparen) << "defined";
      PP.Diag(LParenLoc, diag::note_matching) << "(";
      return true;
    }
    // Consume the ).
    Result.setEnd(PeekTok.getLocation());
    PP.LexNonComment(PeekTok);
  } else {
    // Consume identifier.
    Result.setEnd(PeekTok.getLocation());
    PP.LexNonComment(PeekTok);
  }

  // Success, remember that we saw defined(X).
  DT.State = DefinedTracker::DefinedMacro;
  DT.TheMacro = II;
  return false;
}
Example #2
0
/// EvaluateDefined - Process a 'defined(sym)' expression.
static bool EvaluateDefined(PPValue &Result, Token &PeekTok, DefinedTracker &DT,
                            bool ValueLive, Preprocessor &PP) {
  SourceLocation beginLoc(PeekTok.getLocation());
  Result.setBegin(beginLoc);

  // Get the next token, don't expand it.
  PP.LexUnexpandedNonComment(PeekTok);

  // Two options, it can either be a pp-identifier or a (.
  SourceLocation LParenLoc;
  if (PeekTok.is(tok::l_paren)) {
    // Found a paren, remember we saw it and skip it.
    LParenLoc = PeekTok.getLocation();
    PP.LexUnexpandedNonComment(PeekTok);
  }

  if (PeekTok.is(tok::code_completion)) {
    if (PP.getCodeCompletionHandler())
      PP.getCodeCompletionHandler()->CodeCompleteMacroName(false);
    PP.setCodeCompletionReached();
    PP.LexUnexpandedNonComment(PeekTok);
  }

  // If we don't have a pp-identifier now, this is an error.
  if (PP.CheckMacroName(PeekTok, MU_Other))
    return true;

  // Otherwise, we got an identifier, is it defined to something?
  IdentifierInfo *II = PeekTok.getIdentifierInfo();
  MacroDefinition Macro = PP.getMacroDefinition(II);
  Result.Val = !!Macro;
  Result.Val.setIsUnsigned(false); // Result is signed intmax_t.

  // If there is a macro, mark it used.
  if (Result.Val != 0 && ValueLive)
    PP.markMacroAsUsed(Macro.getMacroInfo());

  // Save macro token for callback.
  Token macroToken(PeekTok);

  // If we are in parens, ensure we have a trailing ).
  if (LParenLoc.isValid()) {
    // Consume identifier.
    Result.setEnd(PeekTok.getLocation());
    PP.LexUnexpandedNonComment(PeekTok);

    if (PeekTok.isNot(tok::r_paren)) {
      PP.Diag(PeekTok.getLocation(), diag::err_pp_expected_after)
          << "'defined'" << tok::r_paren;
      PP.Diag(LParenLoc, diag::note_matching) << tok::l_paren;
      return true;
    }
    // Consume the ).
    Result.setEnd(PeekTok.getLocation());
    PP.LexNonComment(PeekTok);
  } else {
    // Consume identifier.
    Result.setEnd(PeekTok.getLocation());
    PP.LexNonComment(PeekTok);
  }

  // Invoke the 'defined' callback.
  if (PPCallbacks *Callbacks = PP.getPPCallbacks()) {
    Callbacks->Defined(macroToken, Macro,
                       SourceRange(beginLoc, PeekTok.getLocation()));
  }

  // Success, remember that we saw defined(X).
  DT.State = DefinedTracker::DefinedMacro;
  DT.TheMacro = II;
  return false;
}
Example #3
0
/// EvaluateValue - Evaluate the token PeekTok (and any others needed) and
/// return the computed value in Result.  Return true if there was an error
/// parsing.  This function also returns information about the form of the
/// expression in DT.  See above for information on what DT means.
///
/// If ValueLive is false, then this value is being evaluated in a context where
/// the result is not used.  As such, avoid diagnostics that relate to
/// evaluation.
static bool EvaluateValue(PPValue &Result, Token &PeekTok, DefinedTracker &DT,
                          bool ValueLive, Preprocessor &PP) {
  DT.State = DefinedTracker::Unknown;

  if (PeekTok.is(tok::code_completion)) {
    if (PP.getCodeCompletionHandler())
      PP.getCodeCompletionHandler()->CodeCompletePreprocessorExpression();
    PP.setCodeCompletionReached();
    PP.LexNonComment(PeekTok);
  }
      
  // If this token's spelling is a pp-identifier, check to see if it is
  // 'defined' or if it is a macro.  Note that we check here because many
  // keywords are pp-identifiers, so we can't check the kind.
  if (IdentifierInfo *II = PeekTok.getIdentifierInfo()) {
    // Handle "defined X" and "defined(X)".
    if (II->isStr("defined"))
      return(EvaluateDefined(Result, PeekTok, DT, ValueLive, PP));
    
    // If this identifier isn't 'defined' or one of the special
    // preprocessor keywords and it wasn't macro expanded, it turns
    // into a simple 0, unless it is the C++ keyword "true", in which case it
    // turns into "1".
    if (ValueLive &&
        II->getTokenID() != tok::kw_true &&
        II->getTokenID() != tok::kw_false)
      PP.Diag(PeekTok, diag::warn_pp_undef_identifier) << II;
    Result.Val = II->getTokenID() == tok::kw_true;
    Result.Val.setIsUnsigned(false);  // "0" is signed intmax_t 0.
    Result.setRange(PeekTok.getLocation());
    PP.LexNonComment(PeekTok);
    return false;
  }

  switch (PeekTok.getKind()) {
  default:  // Non-value token.
    PP.Diag(PeekTok, diag::err_pp_expr_bad_token_start_expr);
    return true;
  case tok::eod:
  case tok::r_paren:
    // If there is no expression, report and exit.
    PP.Diag(PeekTok, diag::err_pp_expected_value_in_expr);
    return true;
  case tok::numeric_constant: {
    SmallString<64> IntegerBuffer;
    bool NumberInvalid = false;
    StringRef Spelling = PP.getSpelling(PeekTok, IntegerBuffer, 
                                              &NumberInvalid);
    if (NumberInvalid)
      return true; // a diagnostic was already reported

    NumericLiteralParser Literal(Spelling, PeekTok.getLocation(), PP);
    if (Literal.hadError)
      return true; // a diagnostic was already reported.

    if (Literal.isFloatingLiteral() || Literal.isImaginary) {
      PP.Diag(PeekTok, diag::err_pp_illegal_floating_literal);
      return true;
    }
    assert(Literal.isIntegerLiteral() && "Unknown ppnumber");

    // Complain about, and drop, any ud-suffix.
    if (Literal.hasUDSuffix())
      PP.Diag(PeekTok, diag::err_pp_invalid_udl) << /*integer*/1;

    // 'long long' is a C99 or C++11 feature.
    if (!PP.getLangOpts().C99 && Literal.isLongLong) {
      if (PP.getLangOpts().CPlusPlus)
        PP.Diag(PeekTok,
             PP.getLangOpts().CPlusPlus0x ?
             diag::warn_cxx98_compat_longlong : diag::ext_cxx11_longlong);
      else
        PP.Diag(PeekTok, diag::ext_c99_longlong);
    }

    // Parse the integer literal into Result.
    if (Literal.GetIntegerValue(Result.Val)) {
      // Overflow parsing integer literal.
      if (ValueLive) PP.Diag(PeekTok, diag::warn_integer_too_large);
      Result.Val.setIsUnsigned(true);
    } else {
      // Set the signedness of the result to match whether there was a U suffix
      // or not.
      Result.Val.setIsUnsigned(Literal.isUnsigned);

      // Detect overflow based on whether the value is signed.  If signed
      // and if the value is too large, emit a warning "integer constant is so
      // large that it is unsigned" e.g. on 12345678901234567890 where intmax_t
      // is 64-bits.
      if (!Literal.isUnsigned && Result.Val.isNegative()) {
        // Don't warn for a hex literal: 0x8000..0 shouldn't warn.
        if (ValueLive && Literal.getRadix() != 16)
          PP.Diag(PeekTok, diag::warn_integer_too_large_for_signed);
        Result.Val.setIsUnsigned(true);
      }
    }

    // Consume the token.
    Result.setRange(PeekTok.getLocation());
    PP.LexNonComment(PeekTok);
    return false;
  }
  case tok::char_constant:          // 'x'
  case tok::wide_char_constant: {   // L'x'
  case tok::utf16_char_constant:    // u'x'
  case tok::utf32_char_constant:    // U'x'
    // Complain about, and drop, any ud-suffix.
    if (PeekTok.hasUDSuffix())
      PP.Diag(PeekTok, diag::err_pp_invalid_udl) << /*character*/0;

    SmallString<32> CharBuffer;
    bool CharInvalid = false;
    StringRef ThisTok = PP.getSpelling(PeekTok, CharBuffer, &CharInvalid);
    if (CharInvalid)
      return true;

    CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(),
                              PeekTok.getLocation(), PP, PeekTok.getKind());
    if (Literal.hadError())
      return true;  // A diagnostic was already emitted.

    // Character literals are always int or wchar_t, expand to intmax_t.
    const TargetInfo &TI = PP.getTargetInfo();
    unsigned NumBits;
    if (Literal.isMultiChar())
      NumBits = TI.getIntWidth();
    else if (Literal.isWide())
      NumBits = TI.getWCharWidth();
    else if (Literal.isUTF16())
      NumBits = TI.getChar16Width();
    else if (Literal.isUTF32())
      NumBits = TI.getChar32Width();
    else
      NumBits = TI.getCharWidth();

    // Set the width.
    llvm::APSInt Val(NumBits);
    // Set the value.
    Val = Literal.getValue();
    // Set the signedness. UTF-16 and UTF-32 are always unsigned
    if (!Literal.isUTF16() && !Literal.isUTF32())
      Val.setIsUnsigned(!PP.getLangOpts().CharIsSigned);

    if (Result.Val.getBitWidth() > Val.getBitWidth()) {
      Result.Val = Val.extend(Result.Val.getBitWidth());
    } else {
      assert(Result.Val.getBitWidth() == Val.getBitWidth() &&
             "intmax_t smaller than char/wchar_t?");
      Result.Val = Val;
    }

    // Consume the token.
    Result.setRange(PeekTok.getLocation());
    PP.LexNonComment(PeekTok);
    return false;
  }
  case tok::l_paren: {
    SourceLocation Start = PeekTok.getLocation();
    PP.LexNonComment(PeekTok);  // Eat the (.
    // Parse the value and if there are any binary operators involved, parse
    // them.
    if (EvaluateValue(Result, PeekTok, DT, ValueLive, PP)) return true;

    // If this is a silly value like (X), which doesn't need parens, check for
    // !(defined X).
    if (PeekTok.is(tok::r_paren)) {
      // Just use DT unmodified as our result.
    } else {
      // Otherwise, we have something like (x+y), and we consumed '(x'.
      if (EvaluateDirectiveSubExpr(Result, 1, PeekTok, ValueLive, PP))
        return true;

      if (PeekTok.isNot(tok::r_paren)) {
        PP.Diag(PeekTok.getLocation(), diag::err_pp_expected_rparen)
          << Result.getRange();
        PP.Diag(Start, diag::note_matching) << "(";
        return true;
      }
      DT.State = DefinedTracker::Unknown;
    }
    Result.setRange(Start, PeekTok.getLocation());
    PP.LexNonComment(PeekTok);  // Eat the ).
    return false;
  }
  case tok::plus: {
    SourceLocation Start = PeekTok.getLocation();
    // Unary plus doesn't modify the value.
    PP.LexNonComment(PeekTok);
    if (EvaluateValue(Result, PeekTok, DT, ValueLive, PP)) return true;
    Result.setBegin(Start);
    return false;
  }
  case tok::minus: {
    SourceLocation Loc = PeekTok.getLocation();
    PP.LexNonComment(PeekTok);
    if (EvaluateValue(Result, PeekTok, DT, ValueLive, PP)) return true;
    Result.setBegin(Loc);

    // C99 6.5.3.3p3: The sign of the result matches the sign of the operand.
    Result.Val = -Result.Val;

    // -MININT is the only thing that overflows.  Unsigned never overflows.
    bool Overflow = !Result.isUnsigned() && Result.Val.isMinSignedValue();

    // If this operator is live and overflowed, report the issue.
    if (Overflow && ValueLive)
      PP.Diag(Loc, diag::warn_pp_expr_overflow) << Result.getRange();

    DT.State = DefinedTracker::Unknown;
    return false;
  }

  case tok::tilde: {
    SourceLocation Start = PeekTok.getLocation();
    PP.LexNonComment(PeekTok);
    if (EvaluateValue(Result, PeekTok, DT, ValueLive, PP)) return true;
    Result.setBegin(Start);

    // C99 6.5.3.3p4: The sign of the result matches the sign of the operand.
    Result.Val = ~Result.Val;
    DT.State = DefinedTracker::Unknown;
    return false;
  }

  case tok::exclaim: {
    SourceLocation Start = PeekTok.getLocation();
    PP.LexNonComment(PeekTok);
    if (EvaluateValue(Result, PeekTok, DT, ValueLive, PP)) return true;
    Result.setBegin(Start);
    Result.Val = !Result.Val;
    // C99 6.5.3.3p5: The sign of the result is 'int', aka it is signed.
    Result.Val.setIsUnsigned(false);

    if (DT.State == DefinedTracker::DefinedMacro)
      DT.State = DefinedTracker::NotDefinedMacro;
    else if (DT.State == DefinedTracker::NotDefinedMacro)
      DT.State = DefinedTracker::DefinedMacro;
    return false;
  }

  // FIXME: Handle #assert
  }
}
Example #4
0
/// EvaluateDefined - Process a 'defined(sym)' expression.
static bool EvaluateDefined(PPValue &Result, Token &PeekTok, DefinedTracker &DT,
                            bool ValueLive, Preprocessor &PP) {
  SourceLocation beginLoc(PeekTok.getLocation());
  Result.setBegin(beginLoc);

  // Get the next token, don't expand it.
  PP.LexUnexpandedNonComment(PeekTok);

  // Two options, it can either be a pp-identifier or a (.
  SourceLocation LParenLoc;
  if (PeekTok.is(tok::l_paren)) {
    // Found a paren, remember we saw it and skip it.
    LParenLoc = PeekTok.getLocation();
    PP.LexUnexpandedNonComment(PeekTok);
  }

  if (PeekTok.is(tok::code_completion)) {
    if (PP.getCodeCompletionHandler())
      PP.getCodeCompletionHandler()->CodeCompleteMacroName(false);
    PP.setCodeCompletionReached();
    PP.LexUnexpandedNonComment(PeekTok);
  }

  // If we don't have a pp-identifier now, this is an error.
  if (PP.CheckMacroName(PeekTok, MU_Other))
    return true;

  // Otherwise, we got an identifier, is it defined to something?
  IdentifierInfo *II = PeekTok.getIdentifierInfo();
  MacroDefinition Macro = PP.getMacroDefinition(II);
  Result.Val = !!Macro;
  Result.Val.setIsUnsigned(false); // Result is signed intmax_t.

  // If there is a macro, mark it used.
  if (Result.Val != 0 && ValueLive)
    PP.markMacroAsUsed(Macro.getMacroInfo());

  // Save macro token for callback.
  Token macroToken(PeekTok);

  // If we are in parens, ensure we have a trailing ).
  if (LParenLoc.isValid()) {
    // Consume identifier.
    Result.setEnd(PeekTok.getLocation());
    PP.LexUnexpandedNonComment(PeekTok);

    if (PeekTok.isNot(tok::r_paren)) {
      PP.Diag(PeekTok.getLocation(), diag::err_pp_expected_after)
          << "'defined'" << tok::r_paren;
      PP.Diag(LParenLoc, diag::note_matching) << tok::l_paren;
      return true;
    }
    // Consume the ).
    Result.setEnd(PeekTok.getLocation());
    PP.LexNonComment(PeekTok);
  } else {
    // Consume identifier.
    Result.setEnd(PeekTok.getLocation());
    PP.LexNonComment(PeekTok);
  }

  // [cpp.cond]p4:
  //   Prior to evaluation, macro invocations in the list of preprocessing
  //   tokens that will become the controlling constant expression are replaced
  //   (except for those macro names modified by the 'defined' unary operator),
  //   just as in normal text. If the token 'defined' is generated as a result
  //   of this replacement process or use of the 'defined' unary operator does
  //   not match one of the two specified forms prior to macro replacement, the
  //   behavior is undefined.
  // This isn't an idle threat, consider this program:
  //   #define FOO
  //   #define BAR defined(FOO)
  //   #if BAR
  //   ...
  //   #else
  //   ...
  //   #endif
  // clang and gcc will pick the #if branch while Visual Studio will take the
  // #else branch.  Emit a warning about this undefined behavior.
  if (beginLoc.isMacroID()) {
    bool IsFunctionTypeMacro =
        PP.getSourceManager()
            .getSLocEntry(PP.getSourceManager().getFileID(beginLoc))
            .getExpansion()
            .isFunctionMacroExpansion();
    // For object-type macros, it's easy to replace
    //   #define FOO defined(BAR)
    // with
    //   #if defined(BAR)
    //   #define FOO 1
    //   #else
    //   #define FOO 0
    //   #endif
    // and doing so makes sense since compilers handle this differently in
    // practice (see example further up).  But for function-type macros,
    // there is no good way to write
    //   # define FOO(x) (defined(M_ ## x) && M_ ## x)
    // in a different way, and compilers seem to agree on how to behave here.
    // So warn by default on object-type macros, but only warn in -pedantic
    // mode on function-type macros.
    if (IsFunctionTypeMacro)
      PP.Diag(beginLoc, diag::warn_defined_in_function_type_macro);
    else
      PP.Diag(beginLoc, diag::warn_defined_in_object_type_macro);
  }

  // Invoke the 'defined' callback.
  if (PPCallbacks *Callbacks = PP.getPPCallbacks()) {
    Callbacks->Defined(macroToken, Macro,
                       SourceRange(beginLoc, PeekTok.getLocation()));
  }

  // Success, remember that we saw defined(X).
  DT.State = DefinedTracker::DefinedMacro;
  DT.TheMacro = II;
  return false;
}