forked from OSchip/llvm-project
15b9380dfd
Change `sinf` range reduction to mod pi/16 to be shared with `cosf`. Previously, `sinf` used range reduction `mod pi`, but this cannot be used to implement `cosf` since the minimax algorithm for `cosf` does not converge due to critical points at `pi/2`. In order to be able to share the same range reduction functions for both `sinf` and `cosf`, we change the range reduction to `mod pi/16` for the following reasons: - The table size is sufficiently small: 32 entries for `sin(k * pi/16)` with `k = 0..31`. It could be reduced to 16 entries if we treat the final sign separately, with an extra multiplication at the end. - The polynomials' degrees are reduced to 7/8 from 15, with extra computations to combine `sin` and `cos` with trig sum equality. - The number of exceptional cases reduced to 2 (with FMA) and 3 (without FMA). - The latency is reduced while maintaining similar throughput as before. Reviewed By: zimmermann6 Differential Revision: https://reviews.llvm.org/D130629 |
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| .. | ||
| AOR_v20.02 | ||
| benchmarks | ||
| cmake/modules | ||
| config | ||
| docs | ||
| fuzzing | ||
| include | ||
| lib | ||
| loader | ||
| spec | ||
| src | ||
| test | ||
| utils | ||
| .clang-tidy | ||
| .gitignore | ||
| CMakeLists.txt | ||
| LICENSE.TXT | ||
| README.txt | ||
README.txt
LLVM libc ========= This directory and its subdirectories contain source code for llvm-libc, a retargetable implementation of the C standard library. LLVM is open source software. You may freely distribute it under the terms of the license agreement found in LICENSE.txt.