On Thu, Jul 14, 2011 at 6:06 PM, Jeffrey Yasskin <[email protected]> wrote: > On Thu, Jul 14, 2011 at 5:30 PM, Eli Friedman <[email protected]> wrote: >> On Thu, Jul 14, 2011 at 5:06 PM, <[email protected]> wrote: >>> Reviewers: cfe-commits_cs.uiuc.edu, >>> >>> Message: >>> Initial diff at >>> http://codereview.appspot.com/download/issue4728042_1.diff. >>> >>> Description: >>> Use the new APFloat::convertToInt(APSInt) function to simplify uses of >>> convertToInt(integerParts*) and make them more reliable. >>> >>> Relies on http://codereview.appspot.com/4738043. >>> >>> Please review this at http://codereview.appspot.com/4728042/ >>> >>> Affected files: >>> M lib/AST/ExprConstant.cpp >>> M lib/Sema/SemaChecking.cpp >>> >>> >>> Index: lib/AST/ExprConstant.cpp >>> diff --git a/lib/AST/ExprConstant.cpp b/lib/AST/ExprConstant.cpp >>> index >>> 9943222b1dd30d9761731fca984d20d6b578f788..03c0747efba9e8ed9451607b6a33c8b1c9716196 >>> 100644 >>> --- a/lib/AST/ExprConstant.cpp >>> +++ b/lib/AST/ExprConstant.cpp >>> @@ -223,12 +223,10 @@ static APSInt HandleFloatToIntCast(QualType DestType, >>> QualType SrcType, >>> // Determine whether we are converting to unsigned or signed. >>> bool DestSigned = DestType->isSignedIntegerOrEnumerationType(); >>> >>> - // FIXME: Warning for overflow. >>> - uint64_t Space[4]; >>> + APSInt Result(DestWidth, !DestSigned); >>> bool ignored; >>> - (void)Value.convertToInteger(Space, DestWidth, DestSigned, >>> - llvm::APFloat::rmTowardZero, &ignored); >>> - return APSInt(llvm::APInt(DestWidth, 4, Space), !DestSigned); >>> + (void)Value.convertToInteger(Result, llvm::APFloat::rmTowardZero, >>> &ignored); >>> + return Result; >>> } >> >> Why are you removing the "FIXME: Warning for overflow" comment? The >> issue still exists... > > Oops. I thought that was talking about overflowing the 4 slots in > Space. I've put it back. > >>> static APFloat HandleFloatToFloatCast(QualType DestType, QualType SrcType, >>> Index: lib/Sema/SemaChecking.cpp >>> diff --git a/lib/Sema/SemaChecking.cpp b/lib/Sema/SemaChecking.cpp >>> index >>> 267cda8f4016ca935873eac6d22bb82906201051..d1990f3061f353f3152a33d450b971b445d95a10 >>> 100644 >>> --- a/lib/Sema/SemaChecking.cpp >>> +++ b/lib/Sema/SemaChecking.cpp >>> @@ -2990,17 +2990,15 @@ void DiagnoseFloatingLiteralImpCast(Sema &S, >>> FloatingLiteral *FL, QualType T, >>> if (&Value.getSemantics() == &llvm::APFloat::PPCDoubleDouble) >>> return; >>> >>> - // Try to convert this exactly to an 64-bit integer. FIXME: It would be >>> - // nice to support arbitrarily large integers here. >>> + // Try to convert this exactly to an integer. >>> bool isExact = false; >>> - uint64_t IntegerPart; >>> - if (Value.convertToInteger(&IntegerPart, 64, /*isSigned=*/true, >>> + llvm::APSInt IntegerValue(S.Context.getIntWidth(T), >>> + /*isUnsigned=*/false); >>> + if (Value.convertToInteger(IntegerValue, >>> llvm::APFloat::rmTowardZero, &isExact) >>> != llvm::APFloat::opOK || !isExact) >>> return; >>> >>> - llvm::APInt IntegerValue(64, IntegerPart, /*isSigned=*/true); >>> - >>> std::string LiteralValue = IntegerValue.toString(10, /*isSigned=*/true); >>> S.Diag(FL->getExprLoc(), diag::note_fix_integral_float_as_integer) >>> << FixItHint::CreateReplacement(FL->getSourceRange(), LiteralValue); >> >> I was going to ask why you're forcing this to be signed, but then I >> realized it's impossible to write a negative floating-point literal. >> :) > > More because the previously-existing code made it signed. I didn't > think hard enough to notice that negative floating literals are > impossible. Using signed integers may actually be a bug, since if the > target is a uint64, and the floating literal doesn't fit in an int64, > this will fail the conversion even though the result would fit.
Hmm... might actually be a regression for something like "unsigned short x = 60000.;" ? Should be trivial to call isSignedIntegerType() here, though. Otherwise looks fine. -Eli _______________________________________________ cfe-commits mailing list [email protected] http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
