From 1b6a04ca5504955c571d1c97504fb45ea0befee4 Mon Sep 17 00:00:00 2001 From: Valentin Popov Date: Mon, 8 Jan 2024 01:21:28 +0400 Subject: Initial vendor packages Signed-off-by: Valentin Popov --- .../src/imp/atomic128/detect/aarch64_macos.rs | 152 +++++++++++++++++++++ 1 file changed, 152 insertions(+) create mode 100644 vendor/portable-atomic/src/imp/atomic128/detect/aarch64_macos.rs (limited to 'vendor/portable-atomic/src/imp/atomic128/detect/aarch64_macos.rs') diff --git a/vendor/portable-atomic/src/imp/atomic128/detect/aarch64_macos.rs b/vendor/portable-atomic/src/imp/atomic128/detect/aarch64_macos.rs new file mode 100644 index 0000000..d6bf9d0 --- /dev/null +++ b/vendor/portable-atomic/src/imp/atomic128/detect/aarch64_macos.rs @@ -0,0 +1,152 @@ +// 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 { + const OUT_LEN: ffi::c_size_t = core::mem::size_of::() 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::(), + (&mut out as *mut u32).cast::(), + &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 ` 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; + }; +} -- cgit v1.2.3