Check in LLVM r95781.
diff --git a/lib/Lex/PPExpressions.cpp b/lib/Lex/PPExpressions.cpp
new file mode 100644
index 0000000..2a6b2a7
--- /dev/null
+++ b/lib/Lex/PPExpressions.cpp
@@ -0,0 +1,745 @@
+//===--- 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/Lex/MacroInfo.h"
+#include "clang/Lex/LiteralSupport.h"
+#include "clang/Basic/TargetInfo.h"
+#include "clang/Lex/LexDiagnostic.h"
+#include "llvm/ADT/APSInt.h"
+using namespace clang;
+
+/// PPValue - Represents the value of a subexpression of a preprocessor
+/// conditional and the source range covered by it.
+class PPValue {
+ SourceRange Range;
+public:
+ llvm::APSInt Val;
+
+ // Default ctor - Construct an 'invalid' PPValue.
+ PPValue(unsigned BitWidth) : Val(BitWidth) {}
+
+ unsigned getBitWidth() const { return Val.getBitWidth(); }
+ bool isUnsigned() const { return Val.isUnsigned(); }
+
+ const 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); }
+};
+
+static bool EvaluateDirectiveSubExpr(PPValue &LHS, unsigned MinPrec,
+ Token &PeekTok, bool ValueLive,
+ 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;
+};
+
+/// 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;
+}
+
+/// 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 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)
+ 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::eom:
+ 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: {
+ llvm::SmallString<64> IntegerBuffer;
+ IntegerBuffer.resize(PeekTok.getLength());
+ const char *ThisTokBegin = &IntegerBuffer[0];
+ unsigned ActualLength = PP.getSpelling(PeekTok, ThisTokBegin);
+ NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength,
+ 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");
+
+ // long long is a C99 feature.
+ if (!PP.getLangOptions().C99 && !PP.getLangOptions().CPlusPlus0x
+ && Literal.isLongLong)
+ PP.Diag(PeekTok, diag::ext_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'
+ llvm::SmallString<32> CharBuffer;
+ CharBuffer.resize(PeekTok.getLength());
+ const char *ThisTokBegin = &CharBuffer[0];
+ unsigned ActualLength = PP.getSpelling(PeekTok, ThisTokBegin);
+ CharLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength,
+ PeekTok.getLocation(), PP);
+ 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
+ NumBits = TI.getCharWidth();
+
+ // Set the width.
+ llvm::APSInt Val(NumBits);
+ // Set the value.
+ Val = Literal.getValue();
+ // Set the signedness.
+ Val.setIsUnsigned(!PP.getLangOptions().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
+ }
+}
+
+
+
+/// getPrecedence - Return the precedence of the specified binary operator
+/// token. This returns:
+/// ~0 - Invalid token.
+/// 14 -> 3 - various operators.
+/// 0 - 'eom' 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::eom: return 0; // Lowest priority, end of macro.
+ }
+}
+
+
+/// 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());
+ }
+
+ // FIXME: All of these should detect and report overflow??
+ bool Overflow = false;
+ switch (Operator) {
+ default: assert(0 && "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) {
+ Res = LHS.Val / RHS.Val;
+ if (LHS.Val.isSigned()) // MININT/-1 --> overflow.
+ Overflow = LHS.Val.isMinSignedValue() && RHS.Val.isAllOnesValue();
+ } else if (ValueLive) {
+ PP.Diag(OpLoc, diag::err_pp_division_by_zero)
+ << LHS.getRange() << RHS.getRange();
+ return true;
+ }
+ break;
+
+ case tok::star:
+ Res = LHS.Val * RHS.Val;
+ if (Res.isSigned() && LHS.Val != 0 && RHS.Val != 0)
+ Overflow = Res/RHS.Val != LHS.Val || 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 (ShAmt >= LHS.Val.getBitWidth())
+ Overflow = true, ShAmt = LHS.Val.getBitWidth()-1;
+ else if (LHS.isUnsigned())
+ Overflow = false;
+ else if (LHS.Val.isNonNegative()) // Don't allow sign change.
+ Overflow = ShAmt >= LHS.Val.countLeadingZeros();
+ else
+ Overflow = ShAmt >= LHS.Val.countLeadingOnes();
+
+ Res = LHS.Val << ShAmt;
+ 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:
+ Res = LHS.Val + RHS.Val;
+ if (LHS.isUnsigned())
+ Overflow = false;
+ else if (LHS.Val.isNonNegative() == RHS.Val.isNonNegative() &&
+ Res.isNonNegative() != LHS.Val.isNonNegative())
+ Overflow = true; // Overflow for signed addition.
+ break;
+ case tok::minus:
+ Res = LHS.Val - RHS.Val;
+ if (LHS.isUnsigned())
+ Overflow = false;
+ else if (LHS.Val.isNonNegative() != RHS.Val.isNonNegative() &&
+ Res.isNonNegative() != LHS.Val.isNonNegative())
+ Overflow = true; // Overflow for signed subtraction.
+ 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.getLangOptions().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());
+ }
+
+ return false;
+}
+
+/// 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.
+bool Preprocessor::
+EvaluateDirectiveExpression(IdentifierInfo *&IfNDefMacro) {
+ // 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;
+ Lex(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::eom))
+ DiscardUntilEndOfDirective();
+
+ // Restore 'DisableMacroExpansion'.
+ DisableMacroExpansion = DisableMacroExpansionAtStartOfDirective;
+ return false;
+ }
+
+ // 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::eom)) {
+ // 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;
+ }
+
+ // 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, *this)) {
+ // Parse error, skip the rest of the macro line.
+ if (Tok.isNot(tok::eom))
+ DiscardUntilEndOfDirective();
+
+ // Restore 'DisableMacroExpansion'.
+ DisableMacroExpansion = DisableMacroExpansionAtStartOfDirective;
+ return false;
+ }
+
+ // If we aren't at the tok::eom token, something bad happened, like an extra
+ // ')' token.
+ if (Tok.isNot(tok::eom)) {
+ Diag(Tok, diag::err_pp_expected_eol);
+ DiscardUntilEndOfDirective();
+ }
+
+ // Restore 'DisableMacroExpansion'.
+ DisableMacroExpansion = DisableMacroExpansionAtStartOfDirective;
+ return ResVal.Val != 0;
+}
+