forked from OSchip/llvm-project
b9d87d7466
Reduce the range-reduction table size from 128 entries down to 64 entries, and reduce the polynomial's degree from 6 down to 4. Currently we use a degree-6 minimax polynomial on an interval of length 2^-7 around 0 to compute exp2f. Based on the suggestion of @santoshn and the RLIBM project (https://github.com/rutgers-apl/rlibm-prog/blob/main/libm/float/exp2.c) it is possible to have a good polynomial of degree-4 on a subinterval of length 2^(-6) to approximate 2^x. We did try to either reduce the degree of the polynomial down to 3 or increase the interval size to 2^(-5), but in both cases the number of exceptional values exploded. So we settle with using a degree-4 polynomial of the interval of size 2^(-6) around 0. Reviewed By: michaelrj, sivachandra, zimmermann6, santoshn Differential Revision: https://reviews.llvm.org/D122346 |
||
|---|---|---|
| .. | ||
| integration | ||
| src | ||
| utils | ||
| CMakeLists.txt | ||
| ErrnoSetterMatcher.h | ||