| Message ID | 20250425205618.360232-9-adhemerval.zanella@linaro.org |
|---|---|
| State | Accepted |
| Commit | 84977600dace5a7cfcb0918e6757939fd4969839 |
| Headers | show |
| Series | Fix UB in math implementations | expand |
On 4/25/25 4:54 PM, Adhemerval Zanella wrote: > The left shift overflows for 'int', use uint32_t instead. It syncs > with CORE-MATH commit bbfabd99. > > Checked on aarch64-linux-gnu, x86_64-linux-gnu, and i686-linux-gnu. LGTM. Reviewed-by: Carlos O'Donell <carlos@redhat.com> > --- > sysdeps/ieee754/flt-32/s_sinpif.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/sysdeps/ieee754/flt-32/s_sinpif.c b/sysdeps/ieee754/flt-32/s_sinpif.c > index 99a8bbbcf3..c0d15e777b 100644 > --- a/sysdeps/ieee754/flt-32/s_sinpif.c > +++ b/sysdeps/ieee754/flt-32/s_sinpif.c > @@ -3,7 +3,7 @@ > Copyright (c) 2022-2025 Alexei Sibidanov. > > The original version of this file was copied from the CORE-MATH > -project (src/binary32/sinpi/sinpif.c, revision f786e13). > +project (src/binary32/sinpi/sinpif.c, revision bbfabd99. OK. > > Permission is hereby granted, free of charge, to any person obtaining a copy > of this software and associated documentation files (the "Software"), to deal > @@ -51,7 +51,7 @@ __sinpif (float x) > { > if (__glibc_unlikely (s < -6)) > return copysignf (0.0f, x); > - int32_t iq = m << (-s - 1); > + int32_t iq = (uint32_t)m << (-s - 1); > iq &= 127; > if (iq == 0 || iq == 64) > return copysignf (0.0f, x); > @@ -63,10 +63,10 @@ __sinpif (float x) > return z * (0x1.921fb54442d18p+1 + z2 * (-0x1.4abbce625be53p+2)); > } > int32_t si = 25 - s; > - if (__glibc_unlikely (si >= 0 && (m << si) == 0)) > + if (__glibc_unlikely (si >= 0 && ((uint32_t)m << si) == 0)) > return copysignf (0.0f, x); > > - int32_t k = m << (31 - s); > + int32_t k = (uint32_t)m << (31 - s); OK. Cast to uint32_t. > double z = k, z2 = z * z; > double fs = SN[0] + z2 * (SN[1] + z2 * SN[2]); > double fc = CN[0] + z2 * (CN[1] + z2 * CN[2]); ommit bbfabd993a71b049c210b0febfd06d18369fadc1 Author: Paul Zimmermann <Paul.Zimmermann@inria.fr> Date: Mon Mar 17 12:29:20 2025 +0100 various fixes to avoid undefined behavior for binary32 functions (contributed by Ganesh Ajjanagadde <gajjanag@alum.mit.edu> see https://sympa.inria.fr/sympa/arc/core-math/2025-03/msg00007.html)
diff --git a/sysdeps/ieee754/flt-32/s_sinpif.c b/sysdeps/ieee754/flt-32/s_sinpif.c index 99a8bbbcf3..c0d15e777b 100644 --- a/sysdeps/ieee754/flt-32/s_sinpif.c +++ b/sysdeps/ieee754/flt-32/s_sinpif.c @@ -3,7 +3,7 @@ Copyright (c) 2022-2025 Alexei Sibidanov. The original version of this file was copied from the CORE-MATH -project (src/binary32/sinpi/sinpif.c, revision f786e13). +project (src/binary32/sinpi/sinpif.c, revision bbfabd99. Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal @@ -51,7 +51,7 @@ __sinpif (float x) { if (__glibc_unlikely (s < -6)) return copysignf (0.0f, x); - int32_t iq = m << (-s - 1); + int32_t iq = (uint32_t)m << (-s - 1); iq &= 127; if (iq == 0 || iq == 64) return copysignf (0.0f, x); @@ -63,10 +63,10 @@ __sinpif (float x) return z * (0x1.921fb54442d18p+1 + z2 * (-0x1.4abbce625be53p+2)); } int32_t si = 25 - s; - if (__glibc_unlikely (si >= 0 && (m << si) == 0)) + if (__glibc_unlikely (si >= 0 && ((uint32_t)m << si) == 0)) return copysignf (0.0f, x); - int32_t k = m << (31 - s); + int32_t k = (uint32_t)m << (31 - s); double z = k, z2 = z * z; double fs = SN[0] + z2 * (SN[1] + z2 * SN[2]); double fc = CN[0] + z2 * (CN[1] + z2 * CN[2]);