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uucore: only probe hardware features the target can have #14860

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e435dfe
uucore: only probe hardware features the target can have
ChihweiLHBird Sep 22, 2026
ab2c824
fixup! uucore: only probe hardware features the target can have
xtqqczze Sep 25, 2026
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74 changes: 32 additions & 42 deletions src/uucore/src/lib/features/hardware.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -143,17 +143,10 @@ impl CpuFeatures {
}

fn detect_impl() -> Self {
let set = [
(HardwareFeature::Avx512, detect_avx512 as fn() -> bool),
(HardwareFeature::Avx2, detect_avx2),
(HardwareFeature::PclMul, detect_pclmul),
(HardwareFeature::Vmull, detect_vmull),
(HardwareFeature::Sse2, detect_sse2),
(HardwareFeature::Asimd, detect_asimd),
]
.into_iter()
.filter_map(|(feat, detect)| detect().then_some(feat))
.collect();
let set = FEATURE_DETECTORS
.iter()
.filter_map(|(feat, detect)| detect().then_some(*feat))
.collect();

Self { set }
}
Expand Down Expand Up @@ -239,6 +232,33 @@ impl HasHardwareFeatures for SimdPolicy {

// Platform-specific feature detection

/// A feature this architecture can have, with its detector.
type FeatureDetector = (HardwareFeature, fn() -> bool);

#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
const FEATURE_DETECTORS: &[FeatureDetector] = &[
(HardwareFeature::Avx512, detect_avx512),
(HardwareFeature::Avx2, detect_avx2),
(HardwareFeature::PclMul, detect_pclmul),
(HardwareFeature::Sse2, detect_sse2),
];

// bytecount's aarch64 SIMD code, used by wc, is only built for little-endian
// targets, so skip these detectors on big-endian targets.
#[cfg(all(target_arch = "aarch64", target_endian = "little"))]
const FEATURE_DETECTORS: &[FeatureDetector] = &[
(HardwareFeature::Vmull, detect_vmull),
(HardwareFeature::Asimd, detect_asimd),
];

// No hardware feature detectors are currently supported on this target.
#[cfg(not(any(
target_arch = "x86",
target_arch = "x86_64",
all(target_arch = "aarch64", target_endian = "little")
)))]
const FEATURE_DETECTORS: &[FeatureDetector] = &[];

#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
fn detect_avx512() -> bool {
if cfg!(target_os = "android") {
Expand All @@ -249,11 +269,6 @@ fn detect_avx512() -> bool {
}
}

#[cfg(not(any(target_arch = "x86", target_arch = "x86_64")))]
fn detect_avx512() -> bool {
false
}

#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
fn detect_avx2() -> bool {
if cfg!(target_os = "android") {
Expand All @@ -263,11 +278,6 @@ fn detect_avx2() -> bool {
}
}

#[cfg(not(any(target_arch = "x86", target_arch = "x86_64")))]
fn detect_avx2() -> bool {
false
}

#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
fn detect_pclmul() -> bool {
if cfg!(target_os = "android") {
Expand All @@ -277,11 +287,6 @@ fn detect_pclmul() -> bool {
}
}

#[cfg(not(any(target_arch = "x86", target_arch = "x86_64")))]
fn detect_pclmul() -> bool {
false
}

#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
fn detect_sse2() -> bool {
if cfg!(target_os = "android") {
Expand All @@ -291,12 +296,7 @@ fn detect_sse2() -> bool {
}
}

#[cfg(not(any(target_arch = "x86", target_arch = "x86_64")))]
fn detect_sse2() -> bool {
false
}

#[cfg(all(target_arch = "aarch64", target_endian = "little"))]
#[cfg(target_arch = "aarch64")]
fn detect_asimd() -> bool {
if cfg!(target_os = "android") {
false
Expand All @@ -305,11 +305,6 @@ fn detect_asimd() -> bool {
}
}

#[cfg(not(all(target_arch = "aarch64", target_endian = "little")))]
fn detect_asimd() -> bool {
false
}

#[cfg(target_arch = "aarch64")]
fn detect_vmull() -> bool {
// VMULL on 64-bit lanes needs PMULL, an optional extension.
Expand All @@ -321,11 +316,6 @@ fn detect_vmull() -> bool {
}
}

#[cfg(not(target_arch = "aarch64"))]
fn detect_vmull() -> bool {
false
}

// GLIBC_TUNABLES parsing

/// Parse the `glibc.cpu.hwcaps` setting of `GLIBC_TUNABLES` into the set of
Expand Down
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