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 <ebl...@redhat.com>
>> Buglink: https://bugs.launchpad.net/bugs/1881004
>> Signed-off-by: Philippe Mathieu-Daudé <phi...@redhat.com>
>> ---
>> v2: Resend without the Cc: "Toni Wilen <twi...@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 <th...@redhat.com>
>
Thanks!
