mirrors/cosmopolitan
1
0
Fork 0
mirror of https://github.com/jart/cosmopolitan.git synced 2025-03-03 07:29:23 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 1

math: fix fma(x,y,0) when x*y rounds to -0

Browse source 
if x!=0, y!=0, z==0 then

  fma(x,y,z) == x*y

in all rounding modes, while adding z can ruin the sign of 0 if x*y
rounds to -0.
This commit is contained in:
Szabolcs Nagy 2024-04-23 09:21:08 -07:00 • committed by Justine Tunney
parent 01267ea0f5
commit ea3cc4ea0b
No known key found for this signature in database
GPG key ID: BE714B4575D6E328
1 changed files with 1 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
libc/tinymath/fma.c
View file

@ -145,7 +145,7 @@ double fma(double x, double y, double z)
return x*y + z;
if (nz.e >= ZEROINFNAN) {
if (nz.e > ZEROINFNAN) /* z==0 */
return x*y + z;
return x*y;
return z;
}