#[repr(simd)]pub struct __m128i(/* private fields */);
Expand description
128-bit wide integer vector type, x86-specific
This type is the same as the __m128i
type defined by Intel,
representing a 128-bit SIMD register. Usage of this type typically
corresponds to the sse
and up target features for x86/x86_64.
Internally this type may be viewed as:
i8x16
- sixteeni8
variables packed togetheri16x8
- eighti16
variables packed togetheri32x4
- fouri32
variables packed togetheri64x2
- twoi64
variables packed together
(as well as unsigned versions). Each intrinsic may interpret the internal bits differently, check the documentation of the intrinsic to see how it’s being used.
The in-memory representation of this type is the same as the one of an equivalent array (i.e. the in-memory order of elements is the same, and there is no padding); however, the alignment is different and equal to the size of the type. Note that the ABI for function calls may not be the same.
Note that this means that an instance of __m128i
typically just means
a “bag of bits” which is left up to interpretation at the point of use.
Most intrinsics using __m128i
are prefixed with _mm_
and the
integer types tend to correspond to suffixes like “epi8” or “epi32”.
§Examples
#[cfg(target_arch = "x86")]
use std::arch::x86::*;
#[cfg(target_arch = "x86_64")]
use std::arch::x86_64::*;
let all_bytes_zero = _mm_setzero_si128();
let all_bytes_one = _mm_set1_epi8(1);
let four_i32 = _mm_set_epi32(1, 2, 3, 4);
Trait Implementations§
§impl AsBytes for __m128i
impl AsBytes for __m128i
§fn as_bytes_mut(&mut self) -> &mut [u8] ⓘwhere
Self: FromBytes,
fn as_bytes_mut(&mut self) -> &mut [u8] ⓘwhere
Self: FromBytes,
§fn write_to_prefix(&self, bytes: &mut [u8]) -> Option<()>
fn write_to_prefix(&self, bytes: &mut [u8]) -> Option<()>
§impl FromBytes for __m128i
impl FromBytes for __m128i
§fn ref_from_prefix(bytes: &[u8]) -> Option<&Self>where
Self: Sized,
fn ref_from_prefix(bytes: &[u8]) -> Option<&Self>where
Self: Sized,
§fn ref_from_suffix(bytes: &[u8]) -> Option<&Self>where
Self: Sized,
fn ref_from_suffix(bytes: &[u8]) -> Option<&Self>where
Self: Sized,
§fn mut_from_prefix(bytes: &mut [u8]) -> Option<&mut Self>where
Self: Sized + AsBytes,
fn mut_from_prefix(bytes: &mut [u8]) -> Option<&mut Self>where
Self: Sized + AsBytes,
§fn mut_from_suffix(bytes: &mut [u8]) -> Option<&mut Self>where
Self: Sized + AsBytes,
fn mut_from_suffix(bytes: &mut [u8]) -> Option<&mut Self>where
Self: Sized + AsBytes,
§fn slice_from(bytes: &[u8]) -> Option<&[Self]>where
Self: Sized,
fn slice_from(bytes: &[u8]) -> Option<&[Self]>where
Self: Sized,
§fn slice_from_prefix(bytes: &[u8], count: usize) -> Option<(&[Self], &[u8])>where
Self: Sized,
fn slice_from_prefix(bytes: &[u8], count: usize) -> Option<(&[Self], &[u8])>where
Self: Sized,
bytes
as a &[Self]
with length
equal to count
without copying. Read more§fn slice_from_suffix(bytes: &[u8], count: usize) -> Option<(&[u8], &[Self])>where
Self: Sized,
fn slice_from_suffix(bytes: &[u8], count: usize) -> Option<(&[u8], &[Self])>where
Self: Sized,
bytes
as a &[Self]
with length
equal to count
without copying. Read more§fn mut_slice_from(bytes: &mut [u8]) -> Option<&mut [Self]>where
Self: Sized + AsBytes,
fn mut_slice_from(bytes: &mut [u8]) -> Option<&mut [Self]>where
Self: Sized + AsBytes,
§fn mut_slice_from_prefix(
bytes: &mut [u8],
count: usize,
) -> Option<(&mut [Self], &mut [u8])>where
Self: Sized + AsBytes,
fn mut_slice_from_prefix(
bytes: &mut [u8],
count: usize,
) -> Option<(&mut [Self], &mut [u8])>where
Self: Sized + AsBytes,
bytes
as a &mut [Self]
with length
equal to count
without copying. Read more§fn mut_slice_from_suffix(
bytes: &mut [u8],
count: usize,
) -> Option<(&mut [u8], &mut [Self])>where
Self: Sized + AsBytes,
fn mut_slice_from_suffix(
bytes: &mut [u8],
count: usize,
) -> Option<(&mut [u8], &mut [Self])>where
Self: Sized + AsBytes,
bytes
as a &mut [Self]
with length
equal to count
without copying. Read more§fn read_from_prefix(bytes: &[u8]) -> Option<Self>where
Self: Sized,
fn read_from_prefix(bytes: &[u8]) -> Option<Self>where
Self: Sized,
impl Copy for __m128i
Auto Trait Implementations§
impl Freeze for __m128i
impl RefUnwindSafe for __m128i
impl Send for __m128i
impl Sync for __m128i
impl Unpin for __m128i
impl UnwindSafe for __m128i
Blanket Implementations§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
source§impl<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
source§unsafe fn clone_to_uninit(&self, dst: *mut T)
unsafe fn clone_to_uninit(&self, dst: *mut T)
clone_to_uninit
)