chore: move memfd detect to detect crate (#213)

Signed-off-by: usamoi <usamoi@outlook.com>

crates/detect/Cargo.toml

@@ -6,3 +6,4 @@ edition.workspace = true
 [dependencies]
 std_detect = { git = "https://github.com/tensorchord/stdarch.git", branch = "avx512fp16" }
 ctor = "0.2.6"
+rustix.workspace = true

crates/detect/src/lib.rs

@@ -1 +1,2 @@
+pub mod linux;
 pub mod x86_64;

crates/detect/src/linux.rs

@@ -0,0 +1,24 @@
+#![cfg(target_os = "linux")]
+
+use std::sync::atomic::{AtomicBool, Ordering};
+
+static ATOMIC_MEMFD: AtomicBool = AtomicBool::new(false);
+
+pub fn test_memfd() -> bool {
+    use rustix::fs::MemfdFlags;
+    use std::io::ErrorKind;
+    match rustix::fs::memfd_create(".memfd.VECTORS.SUPPORT", MemfdFlags::empty()) {
+        Ok(_) => true,
+        Err(e) if e.kind() == ErrorKind::Unsupported => false,
+        Err(_) => false,
+    }
+}
+
+#[ctor::ctor]
+fn ctor_memfd() {
+    ATOMIC_MEMFD.store(test_memfd(), Ordering::Relaxed);
+}
+
+pub fn detect_memfd() -> bool {
+    ATOMIC_MEMFD.load(Ordering::Relaxed)
+}

crates/detect/src/x86_64.rs

@@ -80,6 +80,6 @@ fn ctor_v2() {
     ATOMIC_V2.store(test_v2(), Ordering::Relaxed);
 }
 
-pub fn _detect_v2() -> bool {
+pub fn detect_v2() -> bool {
     ATOMIC_V2.load(Ordering::Relaxed)
 }

crates/detect/tests/linux.rs

@@ -0,0 +1,6 @@
+#![cfg(target_os = "linux")]
+
+#[test]
+fn print() {
+    assert_eq!(detect::linux::test_memfd(), detect::linux::detect_memfd());
+}

crates/detect/tests/x86_64.rs

@@ -0,0 +1,12 @@
+#![cfg(target_arch = "x86_64")]
+
+#[test]
+fn print() {
+    assert_eq!(
+        detect::x86_64::test_avx512fp16(),
+        detect::x86_64::detect_avx512fp16()
+    );
+    assert_eq!(detect::x86_64::test_v4(), detect::x86_64::detect_v4());
+    assert_eq!(detect::x86_64::test_v3(), detect::x86_64::detect_v3());
+    assert_eq!(detect::x86_64::test_v2(), detect::x86_64::detect_v2());
+}