Message ID | 20200528084833.9531-1-philmd@redhat.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | [v2] fpu/softfloat: Silent 'bitwise negation of a boolean expression' warning | expand |
On 28/05/2020 10.48, Philippe Mathieu-Daudé wrote: > When building with clang version 10.0.0-4ubuntu1, we get: > > CC lm32-softmmu/fpu/softfloat.o > fpu/softfloat.c:3365:13: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] > absZ &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > fpu/softfloat.c:3423:18: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] > absZ0 &= ~ ( ( (uint64_t) ( absZ1<<1 ) == 0 ) & roundNearestEven ); > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > fpu/softfloat.c:3483:18: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] > absZ0 &= ~(((uint64_t)(absZ1<<1) == 0) & roundNearestEven); > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > fpu/softfloat.c:3606:13: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] > zSig &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > fpu/softfloat.c:3760:13: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] > zSig &= ~ ( ( ( roundBits ^ 0x200 ) == 0 ) & roundNearestEven ); > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > fpu/softfloat.c:3987:21: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] > ~ ( ( (uint64_t) ( zSig1<<1 ) == 0 ) & roundNearestEven ); > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > fpu/softfloat.c:4003:22: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] > zSig0 &= ~ ( ( (uint64_t) ( zSig1<<1 ) == 0 ) & roundNearestEven ); > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > fpu/softfloat.c:4273:18: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] > zSig1 &= ~ ( ( zSig2 + zSig2 == 0 ) & roundNearestEven ); > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > Fix by rewriting the fishy bitwise AND of two bools as an int. > > Suggested-by: Eric Blake <eblake@redhat.com> > Buglink: https://bugs.launchpad.net/bugs/1881004 > Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com> > --- > v2: Resend without the Cc: "Toni Wilen <twilen@winuae.net>" tag > --- > fpu/softfloat.c | 33 ++++++++++++++++++++++++--------- > 1 file changed, 24 insertions(+), 9 deletions(-) > > diff --git a/fpu/softfloat.c b/fpu/softfloat.c > index 6c8f2d597a..0dd57eddd7 100644 > --- a/fpu/softfloat.c > +++ b/fpu/softfloat.c > @@ -3362,7 +3362,9 @@ static int32_t roundAndPackInt32(bool zSign, uint64_t absZ, > } > roundBits = absZ & 0x7F; > absZ = ( absZ + roundIncrement )>>7; > - absZ &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); > + if (((roundBits ^ 0x40) == 0) && roundNearestEven) { > + absZ &= ~1; > + } You could get rid of some more parentheses now: if ((roundBits ^ 0x40) == 0 && roundNearestEven) ... also in the other hunks. Anyway: Reviewed-by: Thomas Huth <thuth@redhat.com>
On 5/28/20 10:57 AM, Thomas Huth wrote: > On 28/05/2020 10.48, Philippe Mathieu-Daudé wrote: >> When building with clang version 10.0.0-4ubuntu1, we get: >> >> CC lm32-softmmu/fpu/softfloat.o >> fpu/softfloat.c:3365:13: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] >> absZ &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); >> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> >> fpu/softfloat.c:3423:18: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] >> absZ0 &= ~ ( ( (uint64_t) ( absZ1<<1 ) == 0 ) & roundNearestEven ); >> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> >> fpu/softfloat.c:3483:18: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] >> absZ0 &= ~(((uint64_t)(absZ1<<1) == 0) & roundNearestEven); >> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> >> fpu/softfloat.c:3606:13: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] >> zSig &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); >> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> >> fpu/softfloat.c:3760:13: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] >> zSig &= ~ ( ( ( roundBits ^ 0x200 ) == 0 ) & roundNearestEven ); >> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> >> fpu/softfloat.c:3987:21: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] >> ~ ( ( (uint64_t) ( zSig1<<1 ) == 0 ) & roundNearestEven ); >> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> >> fpu/softfloat.c:4003:22: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] >> zSig0 &= ~ ( ( (uint64_t) ( zSig1<<1 ) == 0 ) & roundNearestEven ); >> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> >> fpu/softfloat.c:4273:18: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] >> zSig1 &= ~ ( ( zSig2 + zSig2 == 0 ) & roundNearestEven ); >> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> >> Fix by rewriting the fishy bitwise AND of two bools as an int. >> >> Suggested-by: Eric Blake <eblake@redhat.com> >> Buglink: https://bugs.launchpad.net/bugs/1881004 >> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com> >> --- >> v2: Resend without the Cc: "Toni Wilen <twilen@winuae.net>" tag >> --- >> fpu/softfloat.c | 33 ++++++++++++++++++++++++--------- >> 1 file changed, 24 insertions(+), 9 deletions(-) >> >> diff --git a/fpu/softfloat.c b/fpu/softfloat.c >> index 6c8f2d597a..0dd57eddd7 100644 >> --- a/fpu/softfloat.c >> +++ b/fpu/softfloat.c >> @@ -3362,7 +3362,9 @@ static int32_t roundAndPackInt32(bool zSign, uint64_t absZ, >> } >> roundBits = absZ & 0x7F; >> absZ = ( absZ + roundIncrement )>>7; >> - absZ &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); >> + if (((roundBits ^ 0x40) == 0) && roundNearestEven) { >> + absZ &= ~1; >> + } > > You could get rid of some more parentheses now: > > if ((roundBits ^ 0x40) == 0 && roundNearestEven) > > ... also in the other hunks. I first wrote if (!(roundBits ^ 0x40) && roundNearestEven) But then thought this would diverge from Eric suggestion, so I kept what he wrote (which is a bit closer to the style of rest of this file). > > Anyway: > Reviewed-by: Thomas Huth <thuth@redhat.com> > Thanks!
On 5/28/20 4:00 AM, Philippe Mathieu-Daudé wrote: > On 5/28/20 10:57 AM, Thomas Huth wrote: >> On 28/05/2020 10.48, Philippe Mathieu-Daudé wrote: >>> When building with clang version 10.0.0-4ubuntu1, we get: In the subject, I'd suggest s/Silent/Silence/ >>> >>> CC lm32-softmmu/fpu/softfloat.o >>> fpu/softfloat.c:3365:13: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] >>> absZ &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); >>> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >>> >>> fpu/softfloat.c:3423:18: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] >>> absZ0 &= ~ ( ( (uint64_t) ( absZ1<<1 ) == 0 ) & roundNearestEven ); >>> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >>> Also, do you need to list all errors, or will just one or two representative errors be sufficient? >>> >>> Fix by rewriting the fishy bitwise AND of two bools as an int. >>> >>> Suggested-by: Eric Blake <eblake@redhat.com> >>> Buglink: https://bugs.launchpad.net/bugs/1881004 >>> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com> >>> --- >>> +++ b/fpu/softfloat.c >>> @@ -3362,7 +3362,9 @@ static int32_t roundAndPackInt32(bool zSign, uint64_t absZ, >>> } >>> roundBits = absZ & 0x7F; >>> absZ = ( absZ + roundIncrement )>>7; >>> - absZ &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); >>> + if (((roundBits ^ 0x40) == 0) && roundNearestEven) { >>> + absZ &= ~1; >>> + } >> >> You could get rid of some more parentheses now: >> >> if ((roundBits ^ 0x40) == 0 && roundNearestEven) >> >> ... also in the other hunks. > > I first wrote > > if (!(roundBits ^ 0x40) && roundNearestEven) > > But then thought this would diverge from Eric suggestion, so I kept what > he wrote (which is a bit closer to the style of rest of this file). I don't mind the patch as-is for minimizing churn and matching existing style, but I also would not be opposed if you wanted to elide unnecessary (). > >> >> Anyway: >> Reviewed-by: Thomas Huth <thuth@redhat.com> >> > > Thanks! > Reviewed-by: Eric Blake <eblake@redhat.com>
On 5/28/20 3:37 PM, Eric Blake wrote: > On 5/28/20 4:00 AM, Philippe Mathieu-Daudé wrote: >> On 5/28/20 10:57 AM, Thomas Huth wrote: >>> On 28/05/2020 10.48, Philippe Mathieu-Daudé wrote: >>>> When building with clang version 10.0.0-4ubuntu1, we get: > > In the subject, I'd suggest s/Silent/Silence/ Don't fit... 73 chars :S I'll use 'Avoid' (or 'Remove'?) instead. > >>>> >>>> CC lm32-softmmu/fpu/softfloat.o >>>> fpu/softfloat.c:3365:13: error: bitwise negation of a boolean >>>> expression; did you mean logical negation? [-Werror,-Wbool-operation] >>>> absZ &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); >>>> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >>>> >>>> fpu/softfloat.c:3423:18: error: bitwise negation of a boolean >>>> expression; did you mean logical negation? [-Werror,-Wbool-operation] >>>> absZ0 &= ~ ( ( (uint64_t) ( absZ1<<1 ) == 0 ) & >>>> roundNearestEven ); >>>> >>>> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >>>> > > Also, do you need to list all errors, or will just one or two > representative errors be sufficient? Fair :) > >>>> >>>> Fix by rewriting the fishy bitwise AND of two bools as an int. >>>> >>>> Suggested-by: Eric Blake <eblake@redhat.com> >>>> Buglink: https://bugs.launchpad.net/bugs/1881004 >>>> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com> >>>> --- > >>>> +++ b/fpu/softfloat.c >>>> @@ -3362,7 +3362,9 @@ static int32_t roundAndPackInt32(bool zSign, >>>> uint64_t absZ, >>>> } >>>> roundBits = absZ & 0x7F; >>>> absZ = ( absZ + roundIncrement )>>7; >>>> - absZ &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); >>>> + if (((roundBits ^ 0x40) == 0) && roundNearestEven) { >>>> + absZ &= ~1; >>>> + } >>> >>> You could get rid of some more parentheses now: >>> >>> if ((roundBits ^ 0x40) == 0 && roundNearestEven) >>> >>> ... also in the other hunks. >> >> I first wrote >> >> if (!(roundBits ^ 0x40) && roundNearestEven) >> >> But then thought this would diverge from Eric suggestion, so I kept what >> he wrote (which is a bit closer to the style of rest of this file). > > I don't mind the patch as-is for minimizing churn and matching existing > style, but I also would not be opposed if you wanted to elide > unnecessary (). OK, thanks for the review! > >> >>> >>> Anyway: >>> Reviewed-by: Thomas Huth <thuth@redhat.com> >>> >> >> Thanks! >> > > Reviewed-by: Eric Blake <eblake@redhat.com> >
diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 6c8f2d597a..0dd57eddd7 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -3362,7 +3362,9 @@ static int32_t roundAndPackInt32(bool zSign, uint64_t absZ, } roundBits = absZ & 0x7F; absZ = ( absZ + roundIncrement )>>7; - absZ &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); + if (((roundBits ^ 0x40) == 0) && roundNearestEven) { + absZ &= ~1; + } z = absZ; if ( zSign ) z = - z; if ( ( absZ>>32 ) || ( z && ( ( z < 0 ) ^ zSign ) ) ) { @@ -3420,7 +3422,9 @@ static int64_t roundAndPackInt64(bool zSign, uint64_t absZ0, uint64_t absZ1, if ( increment ) { ++absZ0; if ( absZ0 == 0 ) goto overflow; - absZ0 &= ~ ( ( (uint64_t) ( absZ1<<1 ) == 0 ) & roundNearestEven ); + if (((absZ1 << 1) == 0) && roundNearestEven) { + absZ0 &= ~1; + } } z = absZ0; if ( zSign ) z = - z; @@ -3480,7 +3484,9 @@ static int64_t roundAndPackUint64(bool zSign, uint64_t absZ0, float_raise(float_flag_invalid, status); return UINT64_MAX; } - absZ0 &= ~(((uint64_t)(absZ1<<1) == 0) & roundNearestEven); + if (((absZ1 << 1) == 0) && roundNearestEven) { + absZ0 &= ~1; + } } if (zSign && absZ0) { @@ -3603,7 +3609,9 @@ static float32 roundAndPackFloat32(bool zSign, int zExp, uint32_t zSig, status->float_exception_flags |= float_flag_inexact; } zSig = ( zSig + roundIncrement )>>7; - zSig &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); + if (((roundBits ^ 0x40) == 0) && roundNearestEven) { + zSig &= ~1; + } if ( zSig == 0 ) zExp = 0; return packFloat32( zSign, zExp, zSig ); @@ -3757,7 +3765,9 @@ static float64 roundAndPackFloat64(bool zSign, int zExp, uint64_t zSig, status->float_exception_flags |= float_flag_inexact; } zSig = ( zSig + roundIncrement )>>10; - zSig &= ~ ( ( ( roundBits ^ 0x200 ) == 0 ) & roundNearestEven ); + if (((roundBits ^ 0x200) == 0) && roundNearestEven) { + zSig &= ~1; + } if ( zSig == 0 ) zExp = 0; return packFloat64( zSign, zExp, zSig ); @@ -3983,8 +3993,9 @@ floatx80 roundAndPackFloatx80(int8_t roundingPrecision, bool zSign, } if ( increment ) { ++zSig0; - zSig0 &= - ~ ( ( (uint64_t) ( zSig1<<1 ) == 0 ) & roundNearestEven ); + if (((zSig1 << 1) == 0) && roundNearestEven) { + zSig0 &= ~1; + } if ( (int64_t) zSig0 < 0 ) zExp = 1; } return packFloatx80( zSign, zExp, zSig0 ); @@ -4000,7 +4011,9 @@ floatx80 roundAndPackFloatx80(int8_t roundingPrecision, bool zSign, zSig0 = UINT64_C(0x8000000000000000); } else { - zSig0 &= ~ ( ( (uint64_t) ( zSig1<<1 ) == 0 ) & roundNearestEven ); + if (((zSig1 << 1) == 0) && roundNearestEven) { + zSig0 &= ~1; + } } } else { @@ -4270,7 +4283,9 @@ static float128 roundAndPackFloat128(bool zSign, int32_t zExp, } if ( increment ) { add128( zSig0, zSig1, 0, 1, &zSig0, &zSig1 ); - zSig1 &= ~ ( ( zSig2 + zSig2 == 0 ) & roundNearestEven ); + if ((zSig2 + zSig2 == 0) && roundNearestEven) { + zSig1 &= ~1; + } } else { if ( ( zSig0 | zSig1 ) == 0 ) zExp = 0;
When building with clang version 10.0.0-4ubuntu1, we get: CC lm32-softmmu/fpu/softfloat.o fpu/softfloat.c:3365:13: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] absZ &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fpu/softfloat.c:3423:18: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] absZ0 &= ~ ( ( (uint64_t) ( absZ1<<1 ) == 0 ) & roundNearestEven ); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fpu/softfloat.c:3483:18: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] absZ0 &= ~(((uint64_t)(absZ1<<1) == 0) & roundNearestEven); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fpu/softfloat.c:3606:13: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] zSig &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fpu/softfloat.c:3760:13: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] zSig &= ~ ( ( ( roundBits ^ 0x200 ) == 0 ) & roundNearestEven ); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fpu/softfloat.c:3987:21: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] ~ ( ( (uint64_t) ( zSig1<<1 ) == 0 ) & roundNearestEven ); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fpu/softfloat.c:4003:22: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] zSig0 &= ~ ( ( (uint64_t) ( zSig1<<1 ) == 0 ) & roundNearestEven ); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fpu/softfloat.c:4273:18: error: bitwise negation of a boolean expression; did you mean logical negation? [-Werror,-Wbool-operation] zSig1 &= ~ ( ( zSig2 + zSig2 == 0 ) & roundNearestEven ); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Fix by rewriting the fishy bitwise AND of two bools as an int. Suggested-by: Eric Blake <eblake@redhat.com> Buglink: https://bugs.launchpad.net/bugs/1881004 Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com> --- v2: Resend without the Cc: "Toni Wilen <twilen@winuae.net>" tag --- fpu/softfloat.c | 33 ++++++++++++++++++++++++--------- 1 file changed, 24 insertions(+), 9 deletions(-)