Struct CpuFeatures 

pub struct CpuFeatures(/* private fields */);

A set of CPU features, named after rustc target_features.

Unlike SimdSupport, this is not a ladder: a kernel can require any combination, such as AVX-512 without FMA or F16C on an AVX host.

use lance_core::utils::cpu::CpuFeatures;

// Implied features are included: AVX2 brings AVX along with it.
let needed = CpuFeatures::from_target_features(&["avx2", "fma"]);
assert!(needed.contains(CpuFeatures::AVX));

// A kernel can run here if the host has every feature it needs, and can
// be called directly, without dispatch, if the build baseline does.
let runnable = CpuFeatures::host().contains(needed);
let inlinable = CpuFeatures::baseline().contains(needed);
assert!(runnable || !inlinable);

Implementations

impl CpuFeatures

pub const SSE2: Self

pub const SSE3: Self

pub const SSSE3: Self

pub const SSE4_1: Self

pub const SSE4_2: Self

pub const POPCNT: Self

pub const AVX: Self

pub const AVX2: Self

pub const FMA: Self

pub const F16C: Self

pub const BMI1: Self

pub const BMI2: Self

pub const AVX512F: Self

pub const AVX512BW: Self

pub const AVX512CD: Self

pub const AVX512DQ: Self

pub const AVX512VL: Self

pub const AVX512FP16: Self

pub const NEON: Self

pub const FP16: Self

pub const LSX: Self

pub const LASX: Self

pub const fn empty() -> Self

The set with no features, which every host supports.

pub const fn is_empty(self) -> bool

Whether the set has no features.

pub const fn union(self, other: Self) -> Self

The features in either set.

pub const fn contains(self, other: Self) -> bool

Whether every feature in other is also in self.

pub fn host() -> Self

Features supported by the host, detected once per process.

pub const fn baseline() -> Self

Features the build enables for all code, e.g. via -C target-cpu.

A kernel whose features are all in the baseline can be called directly and inlined; see Dispatch.

pub const fn from_target_feature(name: &str) -> Option<Self>

The feature set for one rustc target_feature name, including the features rustc enables along with it. None if the name is unknown.

Implied features matter for soundness: #[target_feature(enable = "avx512f")] also lets codegen use AVX2, FMA and F16C, so a kernel declaring it must not run on a host that lacks any of them.

pub const fn from_target_features(names: &[&str]) -> Self

Union of Self::from_target_feature over names.

Panics

Panics if a name is unknown. target_kernel! evaluates this in a const, so a typo is a compile error there.

pub fn names(self) -> impl Iterator<Item = &'static str>

The target_feature names of the features in this set.

Trait Implementations

impl Clone for CpuFeatures

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for CpuFeatures

impl Debug for CpuFeatures

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for CpuFeatures

fn default() -> Self

Returns the “default value” for a type.

impl Eq for CpuFeatures

impl Hash for CpuFeatures

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for CpuFeatures

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for CpuFeatures