diff options
| author | Steve Kargl <kargl@FreeBSD.org> | 2024-06-16 23:41:38 +0000 |
|---|---|---|
| committer | Ed Maste <emaste@FreeBSD.org> | 2024-08-06 21:25:10 +0000 |
| commit | dc39004bc670fe33ae6759816380c93a37268dd6 (patch) | |
| tree | bae5b76a05d911b1be0e414ab6d6a311971630d7 | |
| parent | f06d322e9d925ab56a4aa8210a67637d4d341ab6 (diff) | |
libm: fma: correct zero sign with small inputs
This is a fixed version of 888796ade284.
PR: 277783
Reported by: Victor Stinner
Reviewed by: emaste
MFC after: 1 week
(cherry picked from commit 888796ade2842486d3167067e8034254c38aadd3)
(cherry picked from commit e77ad954bb825983b4346b9cc646c9c910b1be24)
(cherry picked from commit 34f746cc7f8a8dd261027a8b392b76e70adc8438)
| -rw-r--r-- | lib/msun/src/s_fma.c | 4 | ||||
| -rw-r--r-- | lib/msun/src/s_fmal.c | 4 |
2 files changed, 4 insertions, 4 deletions
diff --git a/lib/msun/src/s_fma.c b/lib/msun/src/s_fma.c index 6c889a6a46ca..23a84491dd2a 100644 --- a/lib/msun/src/s_fma.c +++ b/lib/msun/src/s_fma.c @@ -260,14 +260,14 @@ fma(double x, double y, double z) spread = ex + ey; - if (r.hi == 0.0) { + if (r.hi == 0.0 && xy.lo == 0) { /* * When the addends cancel to 0, ensure that the result has * the correct sign. */ fesetround(oround); volatile double vzs = zs; /* XXX gcc CSE bug workaround */ - return (xy.hi + vzs + ldexp(xy.lo, spread)); + return (xy.hi + vzs); } if (oround != FE_TONEAREST) { diff --git a/lib/msun/src/s_fmal.c b/lib/msun/src/s_fmal.c index 80c835d09c2b..2fca20610157 100644 --- a/lib/msun/src/s_fmal.c +++ b/lib/msun/src/s_fmal.c @@ -241,14 +241,14 @@ fmal(long double x, long double y, long double z) spread = ex + ey; - if (r.hi == 0.0) { + if (r.hi == 0.0 && xy.lo == 0) { /* * When the addends cancel to 0, ensure that the result has * the correct sign. */ fesetround(oround); volatile long double vzs = zs; /* XXX gcc CSE bug workaround */ - return (xy.hi + vzs + ldexpl(xy.lo, spread)); + return (xy.hi + vzs); } if (oround != FE_TONEAREST) { |