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Diffstat (limited to 'gnu/llvm/tools/clang/lib/Lex/PPExpressions.cpp')
| -rw-r--r-- | gnu/llvm/tools/clang/lib/Lex/PPExpressions.cpp | 892 |
1 files changed, 0 insertions, 892 deletions
diff --git a/gnu/llvm/tools/clang/lib/Lex/PPExpressions.cpp b/gnu/llvm/tools/clang/lib/Lex/PPExpressions.cpp deleted file mode 100644 index ac01efad9bf..00000000000 --- a/gnu/llvm/tools/clang/lib/Lex/PPExpressions.cpp +++ /dev/null @@ -1,892 +0,0 @@ -//===--- PPExpressions.cpp - Preprocessor Expression Evaluation -----------===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file implements the Preprocessor::EvaluateDirectiveExpression method, -// which parses and evaluates integer constant expressions for #if directives. -// -//===----------------------------------------------------------------------===// -// -// FIXME: implement testing for #assert's. -// -//===----------------------------------------------------------------------===// - -#include "clang/Lex/Preprocessor.h" -#include "clang/Basic/IdentifierTable.h" -#include "clang/Basic/SourceLocation.h" -#include "clang/Basic/SourceManager.h" -#include "clang/Basic/TargetInfo.h" -#include "clang/Basic/TokenKinds.h" -#include "clang/Lex/CodeCompletionHandler.h" -#include "clang/Lex/LexDiagnostic.h" -#include "clang/Lex/LiteralSupport.h" -#include "clang/Lex/MacroInfo.h" -#include "clang/Lex/PPCallbacks.h" -#include "clang/Lex/Token.h" -#include "llvm/ADT/APSInt.h" -#include "llvm/ADT/SmallString.h" -#include "llvm/ADT/StringRef.h" -#include "llvm/Support/ErrorHandling.h" -#include "llvm/Support/SaveAndRestore.h" -#include <cassert> - -using namespace clang; - -namespace { - -/// PPValue - Represents the value of a subexpression of a preprocessor -/// conditional and the source range covered by it. -class PPValue { - SourceRange Range; - IdentifierInfo *II; - -public: - llvm::APSInt Val; - - // Default ctor - Construct an 'invalid' PPValue. - PPValue(unsigned BitWidth) : Val(BitWidth) {} - - // If this value was produced by directly evaluating an identifier, produce - // that identifier. - IdentifierInfo *getIdentifier() const { return II; } - void setIdentifier(IdentifierInfo *II) { this->II = II; } - - unsigned getBitWidth() const { return Val.getBitWidth(); } - bool isUnsigned() const { return Val.isUnsigned(); } - - SourceRange getRange() const { return Range; } - - void setRange(SourceLocation L) { Range.setBegin(L); Range.setEnd(L); } - void setRange(SourceLocation B, SourceLocation E) { - Range.setBegin(B); Range.setEnd(E); - } - void setBegin(SourceLocation L) { Range.setBegin(L); } - void setEnd(SourceLocation L) { Range.setEnd(L); } -}; - -} // end anonymous namespace - -static bool EvaluateDirectiveSubExpr(PPValue &LHS, unsigned MinPrec, - Token &PeekTok, bool ValueLive, - bool &IncludedUndefinedIds, - Preprocessor &PP); - -/// DefinedTracker - This struct is used while parsing expressions to keep track -/// of whether !defined(X) has been seen. -/// -/// With this simple scheme, we handle the basic forms: -/// !defined(X) and !defined X -/// but we also trivially handle (silly) stuff like: -/// !!!defined(X) and +!defined(X) and !+!+!defined(X) and !(defined(X)). -struct DefinedTracker { - /// Each time a Value is evaluated, it returns information about whether the - /// parsed value is of the form defined(X), !defined(X) or is something else. - enum TrackerState { - DefinedMacro, // defined(X) - NotDefinedMacro, // !defined(X) - Unknown // Something else. - } State; - /// TheMacro - When the state is DefinedMacro or NotDefinedMacro, this - /// indicates the macro that was checked. - IdentifierInfo *TheMacro; - bool IncludedUndefinedIds = false; -}; - -/// 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. - DT.IncludedUndefinedIds = !Macro; - - // 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; -} - -/// 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; - - Result.setIdentifier(nullptr); - - if (PeekTok.is(tok::code_completion)) { - if (PP.getCodeCompletionHandler()) - PP.getCodeCompletionHandler()->CodeCompletePreprocessorExpression(); - PP.setCodeCompletionReached(); - PP.LexNonComment(PeekTok); - } - - switch (PeekTok.getKind()) { - default: - // 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 (!II->isCPlusPlusOperatorKeyword()) { - // 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 - if (ValueLive) - PP.Diag(PeekTok, diag::warn_pp_undef_identifier) << II; - Result.Val = 0; - Result.Val.setIsUnsigned(false); // "0" is signed intmax_t 0. - Result.setIdentifier(II); - Result.setRange(PeekTok.getLocation()); - DT.IncludedUndefinedIds = true; - PP.LexNonComment(PeekTok); - return false; - } - } - 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().CPlusPlus11 ? - 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::err_integer_literal_too_large) - << /* Unsigned */ 1; - 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()) { - // Octal, hexadecimal, and binary literals are implicitly unsigned if - // the value does not fit into a signed integer type. - if (ValueLive && Literal.getRadix() == 10) - PP.Diag(PeekTok, diag::ext_integer_literal_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::utf8_char_constant: // u8'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 // char or char8_t - 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.isWide()) - Val.setIsUnsigned(!TargetInfo::isTypeSigned(TI.getWCharType())); - else 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, - DT.IncludedUndefinedIds, 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) << tok::l_paren; - return true; - } - DT.State = DefinedTracker::Unknown; - } - Result.setRange(Start, PeekTok.getLocation()); - Result.setIdentifier(nullptr); - 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); - Result.setIdentifier(nullptr); - return false; - } - case tok::minus: { - SourceLocation Loc = PeekTok.getLocation(); - PP.LexNonComment(PeekTok); - if (EvaluateValue(Result, PeekTok, DT, ValueLive, PP)) return true; - Result.setBegin(Loc); - Result.setIdentifier(nullptr); - - // 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); - Result.setIdentifier(nullptr); - - // 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); - Result.setIdentifier(nullptr); - - if (DT.State == DefinedTracker::DefinedMacro) - DT.State = DefinedTracker::NotDefinedMacro; - else if (DT.State == DefinedTracker::NotDefinedMacro) - DT.State = DefinedTracker::DefinedMacro; - return false; - } - case tok::kw_true: - case tok::kw_false: - Result.Val = PeekTok.getKind() == tok::kw_true; - Result.Val.setIsUnsigned(false); // "0" is signed intmax_t 0. - Result.setIdentifier(PeekTok.getIdentifierInfo()); - Result.setRange(PeekTok.getLocation()); - PP.LexNonComment(PeekTok); - return false; - - // FIXME: Handle #assert - } -} - -/// getPrecedence - Return the precedence of the specified binary operator -/// token. This returns: -/// ~0 - Invalid token. -/// 14 -> 3 - various operators. -/// 0 - 'eod' or ')' -static unsigned getPrecedence(tok::TokenKind Kind) { - switch (Kind) { - default: return ~0U; - case tok::percent: - case tok::slash: - case tok::star: return 14; - case tok::plus: - case tok::minus: return 13; - case tok::lessless: - case tok::greatergreater: return 12; - case tok::lessequal: - case tok::less: - case tok::greaterequal: - case tok::greater: return 11; - case tok::exclaimequal: - case tok::equalequal: return 10; - case tok::amp: return 9; - case tok::caret: return 8; - case tok::pipe: return 7; - case tok::ampamp: return 6; - case tok::pipepipe: return 5; - case tok::question: return 4; - case tok::comma: return 3; - case tok::colon: return 2; - case tok::r_paren: return 0;// Lowest priority, end of expr. - case tok::eod: return 0;// Lowest priority, end of directive. - } -} - -static void diagnoseUnexpectedOperator(Preprocessor &PP, PPValue &LHS, - Token &Tok) { - if (Tok.is(tok::l_paren) && LHS.getIdentifier()) - PP.Diag(LHS.getRange().getBegin(), diag::err_pp_expr_bad_token_lparen) - << LHS.getIdentifier(); - else - PP.Diag(Tok.getLocation(), diag::err_pp_expr_bad_token_binop) - << LHS.getRange(); -} - -/// EvaluateDirectiveSubExpr - Evaluate the subexpression whose first token is -/// PeekTok, and whose precedence is PeekPrec. This returns the result in LHS. -/// -/// 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, such as division by zero warnings. -static bool EvaluateDirectiveSubExpr(PPValue &LHS, unsigned MinPrec, - Token &PeekTok, bool ValueLive, - bool &IncludedUndefinedIds, - Preprocessor &PP) { - unsigned PeekPrec = getPrecedence(PeekTok.getKind()); - // If this token isn't valid, report the error. - if (PeekPrec == ~0U) { - diagnoseUnexpectedOperator(PP, LHS, PeekTok); - return true; - } - - while (true) { - // If this token has a lower precedence than we are allowed to parse, return - // it so that higher levels of the recursion can parse it. - if (PeekPrec < MinPrec) - return false; - - tok::TokenKind Operator = PeekTok.getKind(); - - // If this is a short-circuiting operator, see if the RHS of the operator is - // dead. Note that this cannot just clobber ValueLive. Consider - // "0 && 1 ? 4 : 1 / 0", which is parsed as "(0 && 1) ? 4 : (1 / 0)". In - // this example, the RHS of the && being dead does not make the rest of the - // expr dead. - bool RHSIsLive; - if (Operator == tok::ampamp && LHS.Val == 0) - RHSIsLive = false; // RHS of "0 && x" is dead. - else if (Operator == tok::pipepipe && LHS.Val != 0) - RHSIsLive = false; // RHS of "1 || x" is dead. - else if (Operator == tok::question && LHS.Val == 0) - RHSIsLive = false; // RHS (x) of "0 ? x : y" is dead. - else - RHSIsLive = ValueLive; - - // Consume the operator, remembering the operator's location for reporting. - SourceLocation OpLoc = PeekTok.getLocation(); - PP.LexNonComment(PeekTok); - - PPValue RHS(LHS.getBitWidth()); - // Parse the RHS of the operator. - DefinedTracker DT; - if (EvaluateValue(RHS, PeekTok, DT, RHSIsLive, PP)) return true; - IncludedUndefinedIds = DT.IncludedUndefinedIds; - - // Remember the precedence of this operator and get the precedence of the - // operator immediately to the right of the RHS. - unsigned ThisPrec = PeekPrec; - PeekPrec = getPrecedence(PeekTok.getKind()); - - // If this token isn't valid, report the error. - if (PeekPrec == ~0U) { - diagnoseUnexpectedOperator(PP, RHS, PeekTok); - return true; - } - - // Decide whether to include the next binop in this subexpression. For - // example, when parsing x+y*z and looking at '*', we want to recursively - // handle y*z as a single subexpression. We do this because the precedence - // of * is higher than that of +. The only strange case we have to handle - // here is for the ?: operator, where the precedence is actually lower than - // the LHS of the '?'. The grammar rule is: - // - // conditional-expression ::= - // logical-OR-expression ? expression : conditional-expression - // where 'expression' is actually comma-expression. - unsigned RHSPrec; - if (Operator == tok::question) - // The RHS of "?" should be maximally consumed as an expression. - RHSPrec = getPrecedence(tok::comma); - else // All others should munch while higher precedence. - RHSPrec = ThisPrec+1; - - if (PeekPrec >= RHSPrec) { - if (EvaluateDirectiveSubExpr(RHS, RHSPrec, PeekTok, RHSIsLive, - IncludedUndefinedIds, PP)) - return true; - PeekPrec = getPrecedence(PeekTok.getKind()); - } - assert(PeekPrec <= ThisPrec && "Recursion didn't work!"); - - // Usual arithmetic conversions (C99 6.3.1.8p1): result is unsigned if - // either operand is unsigned. - llvm::APSInt Res(LHS.getBitWidth()); - switch (Operator) { - case tok::question: // No UAC for x and y in "x ? y : z". - case tok::lessless: // Shift amount doesn't UAC with shift value. - case tok::greatergreater: // Shift amount doesn't UAC with shift value. - case tok::comma: // Comma operands are not subject to UACs. - case tok::pipepipe: // Logical || does not do UACs. - case tok::ampamp: // Logical && does not do UACs. - break; // No UAC - default: - Res.setIsUnsigned(LHS.isUnsigned()|RHS.isUnsigned()); - // If this just promoted something from signed to unsigned, and if the - // value was negative, warn about it. - if (ValueLive && Res.isUnsigned()) { - if (!LHS.isUnsigned() && LHS.Val.isNegative()) - PP.Diag(OpLoc, diag::warn_pp_convert_to_positive) << 0 - << LHS.Val.toString(10, true) + " to " + - LHS.Val.toString(10, false) - << LHS.getRange() << RHS.getRange(); - if (!RHS.isUnsigned() && RHS.Val.isNegative()) - PP.Diag(OpLoc, diag::warn_pp_convert_to_positive) << 1 - << RHS.Val.toString(10, true) + " to " + - RHS.Val.toString(10, false) - << LHS.getRange() << RHS.getRange(); - } - LHS.Val.setIsUnsigned(Res.isUnsigned()); - RHS.Val.setIsUnsigned(Res.isUnsigned()); - } - - bool Overflow = false; - switch (Operator) { - default: llvm_unreachable("Unknown operator token!"); - case tok::percent: - if (RHS.Val != 0) - Res = LHS.Val % RHS.Val; - else if (ValueLive) { - PP.Diag(OpLoc, diag::err_pp_remainder_by_zero) - << LHS.getRange() << RHS.getRange(); - return true; - } - break; - case tok::slash: - if (RHS.Val != 0) { - if (LHS.Val.isSigned()) - Res = llvm::APSInt(LHS.Val.sdiv_ov(RHS.Val, Overflow), false); - else - Res = LHS.Val / RHS.Val; - } else if (ValueLive) { - PP.Diag(OpLoc, diag::err_pp_division_by_zero) - << LHS.getRange() << RHS.getRange(); - return true; - } - break; - - case tok::star: - if (Res.isSigned()) - Res = llvm::APSInt(LHS.Val.smul_ov(RHS.Val, Overflow), false); - else - Res = LHS.Val * RHS.Val; - break; - case tok::lessless: { - // Determine whether overflow is about to happen. - if (LHS.isUnsigned()) - Res = LHS.Val.ushl_ov(RHS.Val, Overflow); - else - Res = llvm::APSInt(LHS.Val.sshl_ov(RHS.Val, Overflow), false); - break; - } - case tok::greatergreater: { - // Determine whether overflow is about to happen. - unsigned ShAmt = static_cast<unsigned>(RHS.Val.getLimitedValue()); - if (ShAmt >= LHS.getBitWidth()) { - Overflow = true; - ShAmt = LHS.getBitWidth()-1; - } - Res = LHS.Val >> ShAmt; - break; - } - case tok::plus: - if (LHS.isUnsigned()) - Res = LHS.Val + RHS.Val; - else - Res = llvm::APSInt(LHS.Val.sadd_ov(RHS.Val, Overflow), false); - break; - case tok::minus: - if (LHS.isUnsigned()) - Res = LHS.Val - RHS.Val; - else - Res = llvm::APSInt(LHS.Val.ssub_ov(RHS.Val, Overflow), false); - break; - case tok::lessequal: - Res = LHS.Val <= RHS.Val; - Res.setIsUnsigned(false); // C99 6.5.8p6, result is always int (signed) - break; - case tok::less: - Res = LHS.Val < RHS.Val; - Res.setIsUnsigned(false); // C99 6.5.8p6, result is always int (signed) - break; - case tok::greaterequal: - Res = LHS.Val >= RHS.Val; - Res.setIsUnsigned(false); // C99 6.5.8p6, result is always int (signed) - break; - case tok::greater: - Res = LHS.Val > RHS.Val; - Res.setIsUnsigned(false); // C99 6.5.8p6, result is always int (signed) - break; - case tok::exclaimequal: - Res = LHS.Val != RHS.Val; - Res.setIsUnsigned(false); // C99 6.5.9p3, result is always int (signed) - break; - case tok::equalequal: - Res = LHS.Val == RHS.Val; - Res.setIsUnsigned(false); // C99 6.5.9p3, result is always int (signed) - break; - case tok::amp: - Res = LHS.Val & RHS.Val; - break; - case tok::caret: - Res = LHS.Val ^ RHS.Val; - break; - case tok::pipe: - Res = LHS.Val | RHS.Val; - break; - case tok::ampamp: - Res = (LHS.Val != 0 && RHS.Val != 0); - Res.setIsUnsigned(false); // C99 6.5.13p3, result is always int (signed) - break; - case tok::pipepipe: - Res = (LHS.Val != 0 || RHS.Val != 0); - Res.setIsUnsigned(false); // C99 6.5.14p3, result is always int (signed) - break; - case tok::comma: - // Comma is invalid in pp expressions in c89/c++ mode, but is valid in C99 - // if not being evaluated. - if (!PP.getLangOpts().C99 || ValueLive) - PP.Diag(OpLoc, diag::ext_pp_comma_expr) - << LHS.getRange() << RHS.getRange(); - Res = RHS.Val; // LHS = LHS,RHS -> RHS. - break; - case tok::question: { - // Parse the : part of the expression. - if (PeekTok.isNot(tok::colon)) { - PP.Diag(PeekTok.getLocation(), diag::err_expected) - << tok::colon << LHS.getRange() << RHS.getRange(); - PP.Diag(OpLoc, diag::note_matching) << tok::question; - return true; - } - // Consume the :. - PP.LexNonComment(PeekTok); - - // Evaluate the value after the :. - bool AfterColonLive = ValueLive && LHS.Val == 0; - PPValue AfterColonVal(LHS.getBitWidth()); - DefinedTracker DT; - if (EvaluateValue(AfterColonVal, PeekTok, DT, AfterColonLive, PP)) - return true; - - // Parse anything after the : with the same precedence as ?. We allow - // things of equal precedence because ?: is right associative. - if (EvaluateDirectiveSubExpr(AfterColonVal, ThisPrec, - PeekTok, AfterColonLive, - IncludedUndefinedIds, PP)) - return true; - - // Now that we have the condition, the LHS and the RHS of the :, evaluate. - Res = LHS.Val != 0 ? RHS.Val : AfterColonVal.Val; - RHS.setEnd(AfterColonVal.getRange().getEnd()); - - // Usual arithmetic conversions (C99 6.3.1.8p1): result is unsigned if - // either operand is unsigned. - Res.setIsUnsigned(RHS.isUnsigned() | AfterColonVal.isUnsigned()); - - // Figure out the precedence of the token after the : part. - PeekPrec = getPrecedence(PeekTok.getKind()); - break; - } - case tok::colon: - // Don't allow :'s to float around without being part of ?: exprs. - PP.Diag(OpLoc, diag::err_pp_colon_without_question) - << LHS.getRange() << RHS.getRange(); - return true; - } - - // If this operator is live and overflowed, report the issue. - if (Overflow && ValueLive) - PP.Diag(OpLoc, diag::warn_pp_expr_overflow) - << LHS.getRange() << RHS.getRange(); - - // Put the result back into 'LHS' for our next iteration. - LHS.Val = Res; - LHS.setEnd(RHS.getRange().getEnd()); - RHS.setIdentifier(nullptr); - } -} - -/// EvaluateDirectiveExpression - Evaluate an integer constant expression that -/// may occur after a #if or #elif directive. If the expression is equivalent -/// to "!defined(X)" return X in IfNDefMacro. -Preprocessor::DirectiveEvalResult -Preprocessor::EvaluateDirectiveExpression(IdentifierInfo *&IfNDefMacro) { - SaveAndRestore<bool> PPDir(ParsingIfOrElifDirective, true); - // Save the current state of 'DisableMacroExpansion' and reset it to false. If - // 'DisableMacroExpansion' is true, then we must be in a macro argument list - // in which case a directive is undefined behavior. We want macros to be able - // to recursively expand in order to get more gcc-list behavior, so we force - // DisableMacroExpansion to false and restore it when we're done parsing the - // expression. - bool DisableMacroExpansionAtStartOfDirective = DisableMacroExpansion; - DisableMacroExpansion = false; - - // Peek ahead one token. - Token Tok; - LexNonComment(Tok); - - // C99 6.10.1p3 - All expressions are evaluated as intmax_t or uintmax_t. - unsigned BitWidth = getTargetInfo().getIntMaxTWidth(); - - PPValue ResVal(BitWidth); - DefinedTracker DT; - if (EvaluateValue(ResVal, Tok, DT, true, *this)) { - // Parse error, skip the rest of the macro line. - if (Tok.isNot(tok::eod)) - DiscardUntilEndOfDirective(); - - // Restore 'DisableMacroExpansion'. - DisableMacroExpansion = DisableMacroExpansionAtStartOfDirective; - return {false, DT.IncludedUndefinedIds}; - } - - // If we are at the end of the expression after just parsing a value, there - // must be no (unparenthesized) binary operators involved, so we can exit - // directly. - if (Tok.is(tok::eod)) { - // If the expression we parsed was of the form !defined(macro), return the - // macro in IfNDefMacro. - if (DT.State == DefinedTracker::NotDefinedMacro) - IfNDefMacro = DT.TheMacro; - - // Restore 'DisableMacroExpansion'. - DisableMacroExpansion = DisableMacroExpansionAtStartOfDirective; - return {ResVal.Val != 0, DT.IncludedUndefinedIds}; - } - - // Otherwise, we must have a binary operator (e.g. "#if 1 < 2"), so parse the - // operator and the stuff after it. - if (EvaluateDirectiveSubExpr(ResVal, getPrecedence(tok::question), - Tok, true, DT.IncludedUndefinedIds, *this)) { - // Parse error, skip the rest of the macro line. - if (Tok.isNot(tok::eod)) - DiscardUntilEndOfDirective(); - - // Restore 'DisableMacroExpansion'. - DisableMacroExpansion = DisableMacroExpansionAtStartOfDirective; - return {false, DT.IncludedUndefinedIds}; - } - - // If we aren't at the tok::eod token, something bad happened, like an extra - // ')' token. - if (Tok.isNot(tok::eod)) { - Diag(Tok, diag::err_pp_expected_eol); - DiscardUntilEndOfDirective(); - } - - // Restore 'DisableMacroExpansion'. - DisableMacroExpansion = DisableMacroExpansionAtStartOfDirective; - return {ResVal.Val != 0, DT.IncludedUndefinedIds}; -} |