diff options
Diffstat (limited to 'vendor/portable-atomic/src/imp/atomic128/detect/aarch64_macos.rs')
| -rw-r--r-- | vendor/portable-atomic/src/imp/atomic128/detect/aarch64_macos.rs | 152 |
1 files changed, 0 insertions, 152 deletions
diff --git a/vendor/portable-atomic/src/imp/atomic128/detect/aarch64_macos.rs b/vendor/portable-atomic/src/imp/atomic128/detect/aarch64_macos.rs deleted file mode 100644 index d6bf9d0..0000000 --- a/vendor/portable-atomic/src/imp/atomic128/detect/aarch64_macos.rs +++ /dev/null @@ -1,152 +0,0 @@ -// SPDX-License-Identifier: Apache-2.0 OR MIT - -// Run-time feature detection on aarch64 macOS by using sysctl. -// -// This module is currently only enabled on tests because aarch64 macOS always supports FEAT_LSE and FEAT_LSE2. -// https://github.com/llvm/llvm-project/blob/llvmorg-17.0.0-rc2/llvm/include/llvm/TargetParser/AArch64TargetParser.h#L494 -// -// If macOS supporting Armv9.4-a becomes popular in the future, this module will -// be used to support outline-atomics for FEAT_LSE128/FEAT_LRCPC3. -// -// Refs: https://developer.apple.com/documentation/kernel/1387446-sysctlbyname/determining_instruction_set_characteristics -// -// Note that iOS doesn't support sysctl: -// - https://developer.apple.com/forums/thread/9440 -// - https://nabla-c0d3.github.io/blog/2015/06/16/ios9-security-privacy - -include!("common.rs"); - -use core::ptr; - -// core::ffi::c_* (except c_void) requires Rust 1.64, libc will soon require Rust 1.47 -#[allow(non_camel_case_types)] -mod ffi { - pub(crate) use super::c_types::{c_char, c_int, c_size_t, c_void}; - - extern "C" { - // https://developer.apple.com/documentation/kernel/1387446-sysctlbyname - // https://github.com/apple-oss-distributions/xnu/blob/5c2921b07a2480ab43ec66f5b9e41cb872bc554f/bsd/sys/sysctl.h - // https://github.com/rust-lang/libc/blob/0.2.139/src/unix/bsd/apple/mod.rs#L5167-L5173 - pub(crate) fn sysctlbyname( - name: *const c_char, - old_p: *mut c_void, - old_len_p: *mut c_size_t, - new_p: *mut c_void, - new_len: c_size_t, - ) -> c_int; - } -} - -unsafe fn sysctlbyname32(name: &[u8]) -> Option<u32> { - const OUT_LEN: ffi::c_size_t = core::mem::size_of::<u32>() as ffi::c_size_t; - - debug_assert_eq!(name.last(), Some(&0), "{:?}", name); - debug_assert_eq!(name.iter().filter(|&&v| v == 0).count(), 1, "{:?}", name); - - let mut out = 0_u32; - let mut out_len = OUT_LEN; - // SAFETY: - // - the caller must guarantee that `name` a valid C string. - // - `out_len` does not exceed the size of `out`. - // - `sysctlbyname` is thread-safe. - let res = unsafe { - ffi::sysctlbyname( - name.as_ptr().cast::<ffi::c_char>(), - (&mut out as *mut u32).cast::<ffi::c_void>(), - &mut out_len, - ptr::null_mut(), - 0, - ) - }; - if res != 0 { - return None; - } - debug_assert_eq!(out_len, OUT_LEN); - Some(out) -} - -#[cold] -fn _detect(info: &mut CpuInfo) { - // hw.optional.armv8_1_atomics is available on macOS 11+ (note: aarch64 support was added on macOS 11), - // hw.optional.arm.FEAT_* are only available on macOS 12+. - // Query both names in case future versions of macOS remove the old name. - // https://github.com/golang/go/commit/c15593197453b8bf90fc3a9080ba2afeaf7934ea - // https://github.com/google/boringssl/commit/91e0b11eba517d83b910b20fe3740eeb39ecb37e - // SAFETY: we passed a valid C string. - if unsafe { - sysctlbyname32(b"hw.optional.arm.FEAT_LSE\0").unwrap_or(0) != 0 - || sysctlbyname32(b"hw.optional.armv8_1_atomics\0").unwrap_or(0) != 0 - } { - info.set(CpuInfo::HAS_LSE); - } - // SAFETY: we passed a valid C string. - if unsafe { sysctlbyname32(b"hw.optional.arm.FEAT_LSE2\0").unwrap_or(0) != 0 } { - info.set(CpuInfo::HAS_LSE2); - } - // we currently only use FEAT_LSE and FEAT_LSE2 in outline-atomics. - #[cfg(test)] - { - // SAFETY: we passed a valid C string. - if unsafe { sysctlbyname32(b"hw.optional.arm.FEAT_LSE128\0").unwrap_or(0) != 0 } { - info.set(CpuInfo::HAS_LSE128); - } - // SAFETY: we passed a valid C string. - if unsafe { sysctlbyname32(b"hw.optional.arm.FEAT_LRCPC3\0").unwrap_or(0) != 0 } { - info.set(CpuInfo::HAS_RCPC3); - } - } -} - -#[allow( - clippy::alloc_instead_of_core, - clippy::std_instead_of_alloc, - clippy::std_instead_of_core, - clippy::undocumented_unsafe_blocks, - clippy::wildcard_imports -)] -#[cfg(test)] -mod tests { - use super::*; - - #[test] - fn test_macos() { - unsafe { - assert_eq!(sysctlbyname32(b"hw.optional.armv8_1_atomics\0"), Some(1)); - assert_eq!(sysctlbyname32(b"hw.optional.arm.FEAT_LSE\0"), Some(1)); - assert_eq!(sysctlbyname32(b"hw.optional.arm.FEAT_LSE2\0"), Some(1)); - assert_eq!(sysctlbyname32(b"hw.optional.arm.FEAT_LSE128\0"), None); - assert_eq!(std::io::Error::last_os_error().kind(), std::io::ErrorKind::NotFound); - assert_eq!(sysctlbyname32(b"hw.optional.arm.FEAT_LRCPC\0"), Some(1)); - assert_eq!(sysctlbyname32(b"hw.optional.arm.FEAT_LRCPC2\0"), Some(1)); - assert_eq!(sysctlbyname32(b"hw.optional.arm.FEAT_LRCPC3\0"), None); - assert_eq!(std::io::Error::last_os_error().kind(), std::io::ErrorKind::NotFound); - } - } - - // Static assertions for FFI bindings. - // This checks that FFI bindings defined in this crate, FFI bindings defined - // in libc, and FFI bindings generated for the platform's latest header file - // using bindgen have compatible signatures (or the same values if constants). - // Since this is static assertion, we can detect problems with - // `cargo check --tests --target <target>` run in CI (via TESTS=1 build.sh) - // without actually running tests on these platforms. - // See also tools/codegen/src/ffi.rs. - // TODO(codegen): auto-generate this test - #[allow( - clippy::cast_possible_wrap, - clippy::cast_sign_loss, - clippy::no_effect_underscore_binding - )] - const _: fn() = || { - use test_helper::{libc, sys}; - let mut _sysctlbyname: unsafe extern "C" fn( - *const ffi::c_char, - *mut ffi::c_void, - *mut ffi::c_size_t, - *mut ffi::c_void, - ffi::c_size_t, - ) -> ffi::c_int = ffi::sysctlbyname; - _sysctlbyname = libc::sysctlbyname; - _sysctlbyname = sys::sysctlbyname; - }; -} |