| Message ID | 20220712015717.3602602-2-iii@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | target/s390x: vfmin/vfmax fixes | expand |
On 7/12/22 07:27, Ilya Leoshkevich wrote: > vfmin_res() / vfmax_res() are trying to check whether a and b are both > zeroes, but in reality they check that they are the same kind of zero. > This causes incorrect results when comparing positive and negative > zeroes. > > Fixes: da4807527f3b ("s390x/tcg: Implement VECTOR FP (MAXIMUM|MINIMUM)") > Co-developed-by: Ulrich Weigand<ulrich.weigand@de.ibm.com> > Signed-off-by: Ilya Leoshkevich<iii@linux.ibm.com> > --- > target/s390x/tcg/vec_fpu_helper.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) Reviewed-by: Richard Henderson <richard.henderson@linaro.org> r~
On 12.07.22 03:57, Ilya Leoshkevich wrote: > vfmin_res() / vfmax_res() are trying to check whether a and b are both > zeroes, but in reality they check that they are the same kind of zero. > This causes incorrect results when comparing positive and negative > zeroes. > > Fixes: da4807527f3b ("s390x/tcg: Implement VECTOR FP (MAXIMUM|MINIMUM)") > Co-developed-by: Ulrich Weigand <ulrich.weigand@de.ibm.com> > Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> > --- > target/s390x/tcg/vec_fpu_helper.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/target/s390x/tcg/vec_fpu_helper.c b/target/s390x/tcg/vec_fpu_helper.c > index 2a618a1093..75cf605b9f 100644 > --- a/target/s390x/tcg/vec_fpu_helper.c > +++ b/target/s390x/tcg/vec_fpu_helper.c > @@ -824,7 +824,7 @@ static S390MinMaxRes vfmin_res(uint16_t dcmask_a, uint16_t dcmask_b, > default: > g_assert_not_reached(); > } > - } else if (unlikely(dcmask_a & dcmask_b & DCMASK_ZERO)) { > + } else if (unlikely((dcmask_a & DCMASK_ZERO) && (dcmask_b & DCMASK_ZERO))) { > switch (type) { > case S390_MINMAX_TYPE_JAVA: > return neg_a ? S390_MINMAX_RES_A : S390_MINMAX_RES_B; > @@ -874,7 +874,7 @@ static S390MinMaxRes vfmax_res(uint16_t dcmask_a, uint16_t dcmask_b, > default: > g_assert_not_reached(); > } > - } else if (unlikely(dcmask_a & dcmask_b & DCMASK_ZERO)) { > + } else if (unlikely((dcmask_a & DCMASK_ZERO) && (dcmask_b & DCMASK_ZERO))) { > const bool neg_a = dcmask_a & DCMASK_NEGATIVE; > > switch (type) { Thanks! Reviewed-by: David Hildenbrand <david@redhat.com>
diff --git a/target/s390x/tcg/vec_fpu_helper.c b/target/s390x/tcg/vec_fpu_helper.c index 2a618a1093..75cf605b9f 100644 --- a/target/s390x/tcg/vec_fpu_helper.c +++ b/target/s390x/tcg/vec_fpu_helper.c @@ -824,7 +824,7 @@ static S390MinMaxRes vfmin_res(uint16_t dcmask_a, uint16_t dcmask_b, default: g_assert_not_reached(); } - } else if (unlikely(dcmask_a & dcmask_b & DCMASK_ZERO)) { + } else if (unlikely((dcmask_a & DCMASK_ZERO) && (dcmask_b & DCMASK_ZERO))) { switch (type) { case S390_MINMAX_TYPE_JAVA: return neg_a ? S390_MINMAX_RES_A : S390_MINMAX_RES_B; @@ -874,7 +874,7 @@ static S390MinMaxRes vfmax_res(uint16_t dcmask_a, uint16_t dcmask_b, default: g_assert_not_reached(); } - } else if (unlikely(dcmask_a & dcmask_b & DCMASK_ZERO)) { + } else if (unlikely((dcmask_a & DCMASK_ZERO) && (dcmask_b & DCMASK_ZERO))) { const bool neg_a = dcmask_a & DCMASK_NEGATIVE; switch (type) {
vfmin_res() / vfmax_res() are trying to check whether a and b are both zeroes, but in reality they check that they are the same kind of zero. This causes incorrect results when comparing positive and negative zeroes. Fixes: da4807527f3b ("s390x/tcg: Implement VECTOR FP (MAXIMUM|MINIMUM)") Co-developed-by: Ulrich Weigand <ulrich.weigand@de.ibm.com> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> --- target/s390x/tcg/vec_fpu_helper.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)