use super::*; /// Marker trait for "plain old data". /// /// The point of this trait is that once something is marked "plain old data" /// you can really go to town with the bit fiddling and bit casting. Therefore, /// it's a relatively strong claim to make about a type. Do not add this to your /// type casually. /// /// **Reminder:** The results of casting around bytes between data types are /// _endian dependant_. Little-endian machines are the most common, but /// big-endian machines do exist (and big-endian is also used for "network /// order" bytes). /// /// ## Safety /// /// * The type must be inhabited (eg: no /// [Infallible](core::convert::Infallible)). /// * The type must allow any bit pattern (eg: no `bool` or `char`, which have /// illegal bit patterns). /// * The type must not contain any uninit (or padding) bytes, either in the /// middle or on the end (eg: no `#[repr(C)] struct Foo(u8, u16)`, which has /// padding in the middle, and also no `#[repr(C)] struct Foo(u16, u8)`, which /// has padding on the end). /// * The type needs to have all fields also be `Pod`. /// * The type needs to be `repr(C)` or `repr(transparent)`. In the case of /// `repr(C)`, the `packed` and `align` repr modifiers can be used as long as /// all other rules end up being followed. /// * It is disallowed for types to contain pointer types, `Cell`, `UnsafeCell`, /// atomics, and any other forms of interior mutability. /// * More precisely: A shared reference to the type must allow reads, and /// *only* reads. RustBelt's separation logic is based on the notion that a /// type is allowed to define a sharing predicate, its own invariant that must /// hold for shared references, and this predicate is the reasoning that allow /// it to deal with atomic and cells etc. We require the sharing predicate to /// be trivial and permit only read-only access. pub unsafe trait Pod: Zeroable + Copy + 'static {} unsafe impl Pod for () {} unsafe impl Pod for u8 {} unsafe impl Pod for i8 {} unsafe impl Pod for u16 {} unsafe impl Pod for i16 {} unsafe impl Pod for u32 {} unsafe impl Pod for i32 {} unsafe impl Pod for u64 {} unsafe impl Pod for i64 {} unsafe impl Pod for usize {} unsafe impl Pod for isize {} unsafe impl Pod for u128 {} unsafe impl Pod for i128 {} unsafe impl Pod for f32 {} unsafe impl Pod for f64 {} unsafe impl Pod for Wrapping {} #[cfg(feature = "unsound_ptr_pod_impl")] #[cfg_attr( feature = "nightly_docs", doc(cfg(feature = "unsound_ptr_pod_impl")) )] unsafe impl Pod for *mut T {} #[cfg(feature = "unsound_ptr_pod_impl")] #[cfg_attr( feature = "nightly_docs", doc(cfg(feature = "unsound_ptr_pod_impl")) )] unsafe impl Pod for *const T {} #[cfg(feature = "unsound_ptr_pod_impl")] #[cfg_attr( feature = "nightly_docs", doc(cfg(feature = "unsound_ptr_pod_impl")) )] unsafe impl PodInOption for NonNull {} unsafe impl Pod for PhantomData {} unsafe impl Pod for PhantomPinned {} unsafe impl Pod for ManuallyDrop {} // Note(Lokathor): MaybeUninit can NEVER be Pod. #[cfg(feature = "min_const_generics")] #[cfg_attr(feature = "nightly_docs", doc(cfg(feature = "min_const_generics")))] unsafe impl Pod for [T; N] where T: Pod {} #[cfg(not(feature = "min_const_generics"))] impl_unsafe_marker_for_array!( Pod, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 48, 64, 96, 128, 256, 512, 1024, 2048, 4096 ); impl_unsafe_marker_for_simd!( #[cfg(all(target_arch = "wasm32", feature = "wasm_simd"))] unsafe impl Pod for wasm32::{v128} ); impl_unsafe_marker_for_simd!( #[cfg(all(target_arch = "aarch64", feature = "aarch64_simd"))] unsafe impl Pod for aarch64::{ float32x2_t, float32x2x2_t, float32x2x3_t, float32x2x4_t, float32x4_t, float32x4x2_t, float32x4x3_t, float32x4x4_t, float64x1_t, float64x1x2_t, float64x1x3_t, float64x1x4_t, float64x2_t, float64x2x2_t, float64x2x3_t, float64x2x4_t, int16x4_t, int16x4x2_t, int16x4x3_t, int16x4x4_t, int16x8_t, int16x8x2_t, int16x8x3_t, int16x8x4_t, int32x2_t, int32x2x2_t, int32x2x3_t, int32x2x4_t, int32x4_t, int32x4x2_t, int32x4x3_t, int32x4x4_t, int64x1_t, int64x1x2_t, int64x1x3_t, int64x1x4_t, int64x2_t, int64x2x2_t, int64x2x3_t, int64x2x4_t, int8x16_t, int8x16x2_t, int8x16x3_t, int8x16x4_t, int8x8_t, int8x8x2_t, int8x8x3_t, int8x8x4_t, poly16x4_t, poly16x4x2_t, poly16x4x3_t, poly16x4x4_t, poly16x8_t, poly16x8x2_t, poly16x8x3_t, poly16x8x4_t, poly64x1_t, poly64x1x2_t, poly64x1x3_t, poly64x1x4_t, poly64x2_t, poly64x2x2_t, poly64x2x3_t, poly64x2x4_t, poly8x16_t, poly8x16x2_t, poly8x16x3_t, poly8x16x4_t, poly8x8_t, poly8x8x2_t, poly8x8x3_t, poly8x8x4_t, uint16x4_t, uint16x4x2_t, uint16x4x3_t, uint16x4x4_t, uint16x8_t, uint16x8x2_t, uint16x8x3_t, uint16x8x4_t, uint32x2_t, uint32x2x2_t, uint32x2x3_t, uint32x2x4_t, uint32x4_t, uint32x4x2_t, uint32x4x3_t, uint32x4x4_t, uint64x1_t, uint64x1x2_t, uint64x1x3_t, uint64x1x4_t, uint64x2_t, uint64x2x2_t, uint64x2x3_t, uint64x2x4_t, uint8x16_t, uint8x16x2_t, uint8x16x3_t, uint8x16x4_t, uint8x8_t, uint8x8x2_t, uint8x8x3_t, uint8x8x4_t, } ); impl_unsafe_marker_for_simd!( #[cfg(target_arch = "x86")] unsafe impl Pod for x86::{ __m128i, __m128, __m128d, __m256i, __m256, __m256d, } ); impl_unsafe_marker_for_simd!( #[cfg(target_arch = "x86_64")] unsafe impl Pod for x86_64::{ __m128i, __m128, __m128d, __m256i, __m256, __m256d, } ); #[cfg(feature = "nightly_portable_simd")] #[cfg_attr( feature = "nightly_docs", doc(cfg(feature = "nightly_portable_simd")) )] unsafe impl Pod for core::simd::Simd where T: core::simd::SimdElement + Pod, core::simd::LaneCount: core::simd::SupportedLaneCount, { } impl_unsafe_marker_for_simd!( #[cfg(all(target_arch = "x86", feature = "nightly_stdsimd"))] unsafe impl Pod for x86::{ __m128bh, __m256bh, __m512, __m512bh, __m512d, __m512i, } ); impl_unsafe_marker_for_simd!( #[cfg(all(target_arch = "x86_64", feature = "nightly_stdsimd"))] unsafe impl Pod for x86_64::{ __m128bh, __m256bh, __m512, __m512bh, __m512d, __m512i, } );