diff --git a/crates/core_simd/src/swizzle.rs b/crates/core_simd/src/swizzle.rs index e0edb2cf10a..dbd84543064 100644 --- a/crates/core_simd/src/swizzle.rs +++ b/crates/core_simd/src/swizzle.rs @@ -251,6 +251,50 @@ where Rotate::::swizzle(self) } + /// Shifts the vector elements to the left by `OFFSET`, filling in with + /// `padding` from the right. + #[inline] + #[must_use = "method returns a new vector and does not mutate the original inputs"] + pub fn shift_elements_left(self, padding: T) -> Self { + struct Shift; + + impl Swizzle for Shift { + const INDEX: [usize; N] = const { + let mut index = [N; N]; + let mut i = 0; + while i + OFFSET < N { + index[i] = i + OFFSET; + i += 1; + } + index + }; + } + + Shift::::concat_swizzle(self, Simd::splat(padding)) + } + + /// Shifts the vector elements to the right by `OFFSET`, filling in with + /// `padding` from the left. + #[inline] + #[must_use = "method returns a new vector and does not mutate the original inputs"] + pub fn shift_elements_right(self, padding: T) -> Self { + struct Shift; + + impl Swizzle for Shift { + const INDEX: [usize; N] = const { + let mut index = [N; N]; + let mut i = OFFSET; + while i < N { + index[i] = i - OFFSET; + i += 1; + } + index + }; + } + + Shift::::concat_swizzle(self, Simd::splat(padding)) + } + /// Interleave two vectors. /// /// The resulting vectors contain elements taken alternatively from `self` and `other`, first @@ -451,6 +495,36 @@ where unsafe { Self::from_int_unchecked(self.to_int().rotate_elements_right::()) } } + /// Shifts the mask elements to the left by `OFFSET`, filling in with + /// `padding` from the right. + #[inline] + #[must_use = "method returns a new mask and does not mutate the original inputs"] + pub fn shift_elements_left(self, padding: bool) -> Self { + // Safety: swizzles are safe for masks + unsafe { + Self::from_int_unchecked(self.to_int().shift_elements_left::(if padding { + T::TRUE + } else { + T::FALSE + })) + } + } + + /// Shifts the mask elements to the right by `OFFSET`, filling in with + /// `padding` from the left. + #[inline] + #[must_use = "method returns a new mask and does not mutate the original inputs"] + pub fn shift_elements_right(self, padding: bool) -> Self { + // Safety: swizzles are safe for masks + unsafe { + Self::from_int_unchecked(self.to_int().shift_elements_right::(if padding { + T::TRUE + } else { + T::FALSE + })) + } + } + /// Interleave two masks. /// /// The resulting masks contain elements taken alternatively from `self` and `other`, first diff --git a/crates/core_simd/tests/swizzle.rs b/crates/core_simd/tests/swizzle.rs index 522d71439b7..7001e5f6bf8 100644 --- a/crates/core_simd/tests/swizzle.rs +++ b/crates/core_simd/tests/swizzle.rs @@ -48,6 +48,24 @@ fn rotate() { assert_eq!(a.rotate_elements_right::<5>().to_array(), [4, 1, 2, 3]); } +#[test] +#[cfg_attr(target_arch = "wasm32", wasm_bindgen_test)] +fn shift() { + let a = Simd::from_array([1, 2, 3, 4]); + assert_eq!(a.shift_elements_left::<0>(0).to_array(), [1, 2, 3, 4]); + assert_eq!(a.shift_elements_left::<1>(0).to_array(), [2, 3, 4, 0]); + assert_eq!(a.shift_elements_left::<2>(9).to_array(), [3, 4, 9, 9]); + assert_eq!(a.shift_elements_left::<3>(8).to_array(), [4, 8, 8, 8]); + assert_eq!(a.shift_elements_left::<4>(7).to_array(), [7, 7, 7, 7]); + assert_eq!(a.shift_elements_left::<5>(6).to_array(), [6, 6, 6, 6]); + assert_eq!(a.shift_elements_right::<0>(0).to_array(), [1, 2, 3, 4]); + assert_eq!(a.shift_elements_right::<1>(0).to_array(), [0, 1, 2, 3]); + assert_eq!(a.shift_elements_right::<2>(-1).to_array(), [-1, -1, 1, 2]); + assert_eq!(a.shift_elements_right::<3>(-2).to_array(), [-2, -2, -2, 1]); + assert_eq!(a.shift_elements_right::<4>(-3).to_array(), [-3, -3, -3, -3]); + assert_eq!(a.shift_elements_right::<5>(-4).to_array(), [-4, -4, -4, -4]); +} + #[test] #[cfg_attr(target_arch = "wasm32", wasm_bindgen_test)] fn interleave() {