std::detect - Rust's standard library run-time CPU feature detection![Travis-CI Status] ![Appveyor Status] ![Latest Version] ![docs]
The private std::detect module implements run-time feature detection in Rust's
standard library. This allows detecting whether the CPU the binary runs on
supports certain features, like SIMD instructions.
std::detect APIs are available as part of libstd. Prefer using it via the
standard library than through this crate. Unstable features of std::detect are
available on nightly Rust behind the feature(stdsimd) feature-gate.
If you need run-time feature detection in #[no_std] environments, Rust core
library cannot help you. By design, Rust core is platform independent, but
performing run-time feature detection requires a certain level of cooperation
from the platform.
You can then manually include std_detect as a dependency to get similar
run-time feature detection support than the one offered by Rust's standard
library. We intend to make std_detect more flexible and configurable in this
regard to better serve the needs of #[no_std] targets.
All x86/x86_64 targets are supported on all platforms by querying the
cpuid instruction directly for the features supported by the hardware and
the operating system. std_detect assumes that the binary is an user-space
application. If you need raw support for querying cpuid, consider using the
cupid crate.
Linux:
arm{32, 64}, mips{32,64}{,el}, powerpc{32,64}{,le}: std_detect
supports these on Linux by querying ELF auxiliary vectors (using getauxval
when available), and if that fails, by querying /proc/cpuinfo. arm64: partial support for doing run-time feature detection by directly
querying mrs is implemented for Linux >= 4.11, but not enabled by default.FreeBSD:
arm64: run-time feature detection is implemented by directly querying mrs.This project is licensed under either of
at your option.
Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in std_detect by you, as defined in the Apache-2.0 license,
shall be dual licensed as above, without any additional terms or conditions.