/// 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.LexUnexpandedToken(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.LexUnexpandedToken(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.
// If there is a macro, mark it used.
if (Result.Val != 0 && ValueLive) {
MacroInfo *Macro = PP.getMacroInfo(II);
Macro->setIsUsed(true);
}
// Consume identifier.
Result.setEnd(PeekTok.getLocation());
PP.LexNonComment(PeekTok);
// If we are in parens, ensure we have a trailing ).
if (LParenLoc.isValid()) {
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);
}
// Success, remember that we saw defined(X).
DT.State = DefinedTracker::DefinedMacro;
DT.TheMacro = II;
return false;
}
/// 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;
}
/// 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,
Preprocessor &PP) {
unsigned PeekPrec = getPrecedence(PeekTok.getKind());
// If this token isn't valid, report the error.
if (PeekPrec == ~0U) {
PP.Diag(PeekTok.getLocation(), diag::err_pp_expr_bad_token_binop)
<< LHS.getRange();
return true;
}
while (1) {
// 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;
// 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) {
PP.Diag(PeekTok.getLocation(), diag::err_pp_expr_bad_token_binop)
<< RHS.getRange();
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, 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_lhs_to_positive)
<< 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_rhs_to_positive)
<< 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.
unsigned ShAmt = static_cast<unsigned>(RHS.Val.getLimitedValue());
if (LHS.isUnsigned()) {
Overflow = ShAmt >= LHS.Val.getBitWidth();
if (Overflow)
ShAmt = LHS.Val.getBitWidth()-1;
Res = LHS.Val << ShAmt;
} else {
Res = llvm::APSInt(LHS.Val.sshl_ov(ShAmt, 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_colon)
<< LHS.getRange(), RHS.getRange();
PP.Diag(OpLoc, diag::note_matching) << "?";
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, 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());
}
}
/// 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;
}
/// 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;
}