The branch main has been updated by emaste:
URL:
https://cgit.FreeBSD.org/src/commit/?id=888796ade2842486d3167067e8034254c38aadd3
commit 888796ade2842486d3167067e8034254c38aadd3
Author: Ed Maste <ema...@freebsd.org>
AuthorDate: 2024-03-19 14:31:39 +0000
Commit: Ed Maste <ema...@freebsd.org>
CommitDate: 2024-06-08 15:55:36 +0000
libm: fma: correct zero sign with small inputs
PR: 277783
Reported by: Victor Stinner
Submitted by: kargl
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D44433
---
lib/msun/src/s_fma.c | 4 +++-
lib/msun/src/s_fmal.c | 4 +++-
2 files changed, 6 insertions(+), 2 deletions(-)
diff --git a/lib/msun/src/s_fma.c b/lib/msun/src/s_fma.c
index b8a342646d85..4d08b40cc71a 100644
--- a/lib/msun/src/s_fma.c
+++ b/lib/msun/src/s_fma.c
@@ -267,7 +267,9 @@ fma(double x, double y, double z)
*/
fesetround(oround);
volatile double vzs = zs; /* XXX gcc CSE bug workaround */
- return (xy.hi + vzs + ldexp(xy.lo, spread));
+ xs = ldexp(xy.lo, spread);
+ xy.hi += vzs;
+ return (xy.hi == 0 ? xs : xy.hi + xs);
}
if (oround != FE_TONEAREST) {
diff --git a/lib/msun/src/s_fmal.c b/lib/msun/src/s_fmal.c
index 3d333632127c..12f9c364670b 100644
--- a/lib/msun/src/s_fmal.c
+++ b/lib/msun/src/s_fmal.c
@@ -248,7 +248,9 @@ fmal(long double x, long double y, long double z)
*/
fesetround(oround);
volatile long double vzs = zs; /* XXX gcc CSE bug workaround */
- return (xy.hi + vzs + ldexpl(xy.lo, spread));
+ xs = ldexpl(xy.lo, spread);
+ xy.hi += vzs;
+ return (xy.hi == 0 ? xs : xy.hi + xs);
}
if (oround != FE_TONEAREST) {
