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path: root/libc/src/math/generic/tanf.cpp
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2025-04-08[libc][math] Fix signaling NaN handling for math functions. (#133347)wldfngrs
Add tests for signaling NaNs, and fix function behavior for handling signaling NaN input. Fixes https://github.com/llvm/llvm-project/issues/124812
2025-03-11[libc][math] Skip checking for exceptional values when ↵lntue
LIBC_MATH_SKIP_ACCURATE_PASS is set. (#130811)
2025-03-11[libc] Provide more fine-grained control of FMA instruction for ARM targets. ↵lntue
(#130700)
2024-10-05[libc] remove errno.h includes (#110934)Job Henandez Lara
2024-07-12[libc] Migrate to using LIBC_NAMESPACE_DECL for namespace declaration (#98597)Petr Hosek
This is a part of #97655.
2024-07-12Revert "[libc] Migrate to using LIBC_NAMESPACE_DECL for namespace ↵Mehdi Amini
declaration" (#98593) Reverts llvm/llvm-project#98075 bots are broken
2024-07-11[libc] Migrate to using LIBC_NAMESPACE_DECL for namespace declaration (#98075)Petr Hosek
This is a part of #97655.
2024-01-30[libc][NFC] Rename `FPBits` nan functions (#79998)Guillaume Chatelet
- [libc][NFC] Rename FPBits nan functions - rename build_signaling_nan in signaling_nan - rename build_quiet_nan to quiet_nan
2024-01-23[reland][libc] Remove unnecessary `FPBits` functions and properties (#79128)Guillaume Chatelet
- reland #79113 - Fix aarch64 RISC-V build
2024-01-23Revert "[libc] Remove unnecessary `FPBits` functions and properties" (#79118)Guillaume Chatelet
Reverts llvm/llvm-project#79113 It broke aarch64 build bot machines.
2024-01-23[libc] Remove unnecessary `FPBits` functions and properties (#79113)Guillaume Chatelet
This patch reduces the surface of `FPBits`.
2023-09-26[libc] Mass replace enclosing namespace (#67032)Guillaume Chatelet
This is step 4 of https://discourse.llvm.org/t/rfc-customizable-namespace-to-allow-testing-the-libc-when-the-system-libc-is-also-llvms-libc/73079
2023-03-23[libc] Fix some math conversion warningsAlex Brachet
Differential Revision: https://reviews.llvm.org/D146738
2023-03-07[libc][math] Switch math functions to use libc_errno and fix some errno and ↵Tue Ly
floating point exceptions. Switch math functions to use libc_errno and fix some errno and floating point exceptions Reviewed By: sivachandra Differential Revision: https://reviews.llvm.org/D145349
2023-02-24[libc][math] Set floating point exceptions for exp*f, sinhf, and coshf.Tue Ly
Set FE_OVERFLOW and FE_UNDERFLOW for expf, exp2f, exp10f, expm1f, sinhf and coshf. Reviewed By: sivachandra, renyichen Differential Revision: https://reviews.llvm.org/D144340
2023-02-10[libc] Move likely/unlikely to the optimization headerGuillaume Chatelet
2023-02-09[libc][NFC] Move cpu_features.h to properties subfolderGuillaume Chatelet
2023-02-07[libc][NFC] Rename macrosGuillaume Chatelet
2023-02-07[libc][NFC] Move attributes from common to macros folderGuillaume Chatelet
2023-02-07[libc][NFC] Move cpu_features to macros folderGuillaume Chatelet
2023-02-01[libc][math] Fix setting exceptional value for tanf to work with gcc.Tue Ly
See https://github.com/llvm/llvm-project/issues/59866 Reviewed By: sivachandra Differential Revision: https://reviews.llvm.org/D143098
2023-01-25[libc][NFC] Detect host CPU features using try_compile instead of try_run.Guillaume Chatelet
This implements the same behavior as D141997 but makes sure that the same detection mechanism is used between CMake and source code. Reviewed By: sivachandra, lntue Differential Revision: https://reviews.llvm.org/D142108
2023-01-24Revert D142108 "[reland][libc][NFC] Detect host CPU features using ↵Guillaume Chatelet
try_compile instead of try_run." The build bots are failing. This reverts commit c84d74f5bfe810744de1268eb0516a6622e4aa73.
2023-01-24[reland][libc][NFC] Detect host CPU features using try_compile instead of ↵Guillaume Chatelet
try_run. This implements the same behavior as D141997 but makes sure that the same detection mechanism is used between CMake and source code. Differential Revision: https://reviews.llvm.org/D142108
2023-01-23Revert D142108 "[libc][NFC] Detect host CPU features using try_compile ↵Guillaume Chatelet
instead of try_run." Build bots are failing. https://lab.llvm.org/buildbot/#/builders/90/builds/44634 This reverts commit 9acc2f37bdfce08ca0c2faec03392db10d1bb7a9.
2023-01-23[libc][NFC] Detect host CPU features using try_compile instead of try_run.Guillaume Chatelet
This implements the same behavior as D141997 but makes sure that the same detection mechanism is used between CMake and source code. Differential Revision: https://reviews.llvm.org/D142108
2022-09-26[libc][math] Simplify tanf implementation and improve its performance.Tue Ly
Simplify `tanf` implementation and improve its performance. Completely reuse the implementation of `sinf`, `cosf`, `sincosf` and use the definition `tan(x) = sin(x)/cos(x)`. Performance benchmark using perf tool from the CORE-MATH project on Ryzen 1700: ``` $ CORE_MATH_PERF_MODE="rdtsc" ./perf.sh tanf GNU libc version: 2.35 GNU libc release: stable CORE-MATH reciprocal throughput : 18.558 System LIBC reciprocal throughput : 49.919 BEFORE: LIBC reciprocal throughput : 36.480 LIBC reciprocal throughput : 27.217 (with `-msse4.2` flag) LIBC reciprocal throughput : 20.205 (with `-mfma` flag) AFTER: LIBC reciprocal throughput : 30.337 LIBC reciprocal throughput : 21.072 (with `-msse4.2` flag) LIBC reciprocal throughput : 15.804 (with `-mfma` flag) $ CORE_MATH_PERF_MODE="rdtsc" ./perf.sh tanf --latency GNU libc version: 2.35 GNU libc release: stable CORE-MATH latency : 56.702 System LIBC latency : 107.206 BEFORE LIBC latency : 97.598 LIBC latency : 91.119 (with `-msse4.2` flag) LIBC latency : 82.655 (with `-mfma` flag) AFTER LIBC latency : 74.560 LIBC latency : 66.575 (with `-msse4.2` flag) LIBC latency : 61.636 (with `-mfma` flag) ``` Reviewed By: zimmermann6 Differential Revision: https://reviews.llvm.org/D134575
2022-09-01[libc][NFC] Use cpp::optional for checking exceptional values of math functions.Tue Ly
Update the utility functions for checking exceptional values of math functions to use cpp::optional return values. Reviewed By: sivachandra Differential Revision: https://reviews.llvm.org/D133134
2022-08-12[libc] Implement tanf function correctly rounded for all rounding modes.Tue Ly
Implement tanf function correctly rounded for all rounding modes. We use the range reduction that is shared with `sinf`, `cosf`, and `sincosf`: ``` k = round(x * 32/pi) and y = x * (32/pi) - k. ``` Then we use the tangent of sum formula: ``` tan(x) = tan((k + y)* pi/32) = tan((k mod 32) * pi / 32 + y * pi/32) = (tan((k mod 32) * pi/32) + tan(y * pi/32)) / (1 - tan((k mod 32) * pi/32) * tan(y * pi/32)) ``` We need to make a further reduction when `k mod 32 >= 16` due to the pole at `pi/2` of `tan(x)` function: ``` if (k mod 32 >= 16): k = k - 31, y = y - 1.0 ``` And to compute the final result, we store `tan(k * pi/32)` for `k = -15..15` in a table of 32 double values, and evaluate `tan(y * pi/32)` with a degree-11 minimax odd polynomial generated by Sollya with: ``` > P = fpminimax(tan(y * pi/32)/y, [|0, 2, 4, 6, 8, 10|], [|D...|], [0, 1.5]); ``` Performance benchmark using `perf` tool from the CORE-MATH project on Ryzen 1700: ``` $ CORE_MATH_PERF_MODE="rdtsc" ./perf.sh tanf CORE-MATH reciprocal throughput : 18.586 System LIBC reciprocal throughput : 50.068 LIBC reciprocal throughput : 33.823 LIBC reciprocal throughput : 25.161 (with `-msse4.2` flag) LIBC reciprocal throughput : 19.157 (with `-mfma` flag) $ CORE_MATH_PERF_MODE="rdtsc" ./perf.sh tanf --latency GNU libc version: 2.31 GNU libc release: stable CORE-MATH latency : 55.630 System LIBC latency : 106.264 LIBC latency : 96.060 LIBC latency : 90.727 (with `-msse4.2` flag) LIBC latency : 82.361 (with `-mfma` flag) ``` Reviewed By: orex Differential Revision: https://reviews.llvm.org/D131715
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