README.contributors
1Code in this sub-directory should follow the GNU Coding Standard, but it is
2not expected to be upstreamed into glibc without modification, so
3glibc-specific conventions need not be followed.
4
5The requirements for portable code apply to non-portable code with the
6following differences:
7
8
91. Worst-case ULP error should be encoded in filenames (e.g. sin_u35.c). There
10 are no specific restrictions on acceptable ULP error, but if functions
11 provide significantly less accuracy than portable equivalents then a clear
12 justification for inclusion should be stated in comments at the top of the
13 source file. Error bounds of the approximation should be clearly documented
14 in comments.
15
162. Functions are assumed to support round-to-nearest mode by default, unless
17 stated; other rounding modes are not required to be provided.
18
193. Handling of special cases may be relaxed for vector functions. Checking
20 whether each vector lane contains special values such as NaN, Inf or
21 denormal numbers can prove too costly for vector functions. This is often
22 not required since vector functions are typically used along with aggressive
23 compiler optimization flags.
24