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author | Valentin Popov <valentin@popov.link> | 2024-01-08 00:21:28 +0300 |
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committer | Valentin Popov <valentin@popov.link> | 2024-01-08 00:21:28 +0300 |
commit | 1b6a04ca5504955c571d1c97504fb45ea0befee4 (patch) | |
tree | 7579f518b23313e8a9748a88ab6173d5e030b227 /vendor/simd-adler32/src/imp/wasm.rs | |
parent | 5ecd8cf2cba827454317368b68571df0d13d7842 (diff) | |
download | fparkan-1b6a04ca5504955c571d1c97504fb45ea0befee4.tar.xz fparkan-1b6a04ca5504955c571d1c97504fb45ea0befee4.zip |
Initial vendor packages
Signed-off-by: Valentin Popov <valentin@popov.link>
Diffstat (limited to 'vendor/simd-adler32/src/imp/wasm.rs')
-rw-r--r-- | vendor/simd-adler32/src/imp/wasm.rs | 217 |
1 files changed, 217 insertions, 0 deletions
diff --git a/vendor/simd-adler32/src/imp/wasm.rs b/vendor/simd-adler32/src/imp/wasm.rs new file mode 100644 index 0000000..5a9152b --- /dev/null +++ b/vendor/simd-adler32/src/imp/wasm.rs @@ -0,0 +1,217 @@ +use super::Adler32Imp; + +/// Resolves update implementation if CPU supports simd128 instructions. +pub fn get_imp() -> Option<Adler32Imp> { + get_imp_inner() +} + +#[inline] +#[cfg(target_feature = "simd128")] +fn get_imp_inner() -> Option<Adler32Imp> { + Some(imp::update) +} + +#[inline] +#[cfg(not(target_feature = "simd128"))] +fn get_imp_inner() -> Option<Adler32Imp> { + None +} + +#[cfg(target_feature = "simd128")] +mod imp { + const MOD: u32 = 65521; + const NMAX: usize = 5552; + const BLOCK_SIZE: usize = 32; + const CHUNK_SIZE: usize = NMAX / BLOCK_SIZE * BLOCK_SIZE; + + #[cfg(target_arch = "wasm32")] + use core::arch::wasm32::*; + #[cfg(target_arch = "wasm64")] + use core::arch::wasm64::*; + + pub fn update(a: u16, b: u16, data: &[u8]) -> (u16, u16) { + update_imp(a, b, data) + } + + #[inline] + #[target_feature(enable = "simd128")] + fn update_imp(a: u16, b: u16, data: &[u8]) -> (u16, u16) { + let mut a = a as u32; + let mut b = b as u32; + + let chunks = data.chunks_exact(CHUNK_SIZE); + let remainder = chunks.remainder(); + for chunk in chunks { + update_chunk_block(&mut a, &mut b, chunk); + } + + update_block(&mut a, &mut b, remainder); + + (a as u16, b as u16) + } + + fn update_chunk_block(a: &mut u32, b: &mut u32, chunk: &[u8]) { + debug_assert_eq!( + chunk.len(), + CHUNK_SIZE, + "Unexpected chunk size (expected {}, got {})", + CHUNK_SIZE, + chunk.len() + ); + + reduce_add_blocks(a, b, chunk); + + *a %= MOD; + *b %= MOD; + } + + fn update_block(a: &mut u32, b: &mut u32, chunk: &[u8]) { + debug_assert!( + chunk.len() <= CHUNK_SIZE, + "Unexpected chunk size (expected <= {}, got {})", + CHUNK_SIZE, + chunk.len() + ); + + for byte in reduce_add_blocks(a, b, chunk) { + *a += *byte as u32; + *b += *a; + } + + *a %= MOD; + *b %= MOD; + } + + #[inline(always)] + fn reduce_add_blocks<'a>(a: &mut u32, b: &mut u32, chunk: &'a [u8]) -> &'a [u8] { + if chunk.len() < BLOCK_SIZE { + return chunk; + } + + let blocks = chunk.chunks_exact(BLOCK_SIZE); + let blocks_remainder = blocks.remainder(); + + let weight_hi_v = get_weight_hi(); + let weight_lo_v = get_weight_lo(); + + let mut p_v = u32x4(*a * blocks.len() as u32, 0, 0, 0); + let mut a_v = u32x4(0, 0, 0, 0); + let mut b_v = u32x4(*b, 0, 0, 0); + + for block in blocks { + let block_ptr = block.as_ptr() as *const v128; + let v_lo = unsafe { block_ptr.read_unaligned() }; + let v_hi = unsafe { block_ptr.add(1).read_unaligned() }; + + p_v = u32x4_add(p_v, a_v); + + a_v = u32x4_add(a_v, u32x4_extadd_quarters_u8x16(v_lo)); + let mad = i32x4_dot_i8x16(v_lo, weight_lo_v); + b_v = u32x4_add(b_v, mad); + + a_v = u32x4_add(a_v, u32x4_extadd_quarters_u8x16(v_hi)); + let mad = i32x4_dot_i8x16(v_hi, weight_hi_v); + b_v = u32x4_add(b_v, mad); + } + + b_v = u32x4_add(b_v, u32x4_shl(p_v, 5)); + + *a += reduce_add(a_v); + *b = reduce_add(b_v); + + blocks_remainder + } + + #[inline(always)] + fn i32x4_dot_i8x16(a: v128, b: v128) -> v128 { + let a_lo = u16x8_extend_low_u8x16(a); + let a_hi = u16x8_extend_high_u8x16(a); + + let b_lo = u16x8_extend_low_u8x16(b); + let b_hi = u16x8_extend_high_u8x16(b); + + let lo = i32x4_dot_i16x8(a_lo, b_lo); + let hi = i32x4_dot_i16x8(a_hi, b_hi); + + i32x4_add(lo, hi) + } + + #[inline(always)] + fn u32x4_extadd_quarters_u8x16(a: v128) -> v128 { + u32x4_extadd_pairwise_u16x8(u16x8_extadd_pairwise_u8x16(a)) + } + + #[inline(always)] + fn reduce_add(v: v128) -> u32 { + let arr: [u32; 4] = unsafe { std::mem::transmute(v) }; + let mut sum = 0u32; + for val in arr { + sum = sum.wrapping_add(val); + } + sum + } + + #[inline(always)] + fn get_weight_lo() -> v128 { + u8x16( + 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, + ) + } + + #[inline(always)] + fn get_weight_hi() -> v128 { + u8x16(16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1) + } +} + +#[cfg(test)] +mod tests { + use rand::Rng; + + #[test] + fn zeroes() { + assert_sum_eq(&[]); + assert_sum_eq(&[0]); + assert_sum_eq(&[0, 0]); + assert_sum_eq(&[0; 100]); + assert_sum_eq(&[0; 1024]); + assert_sum_eq(&[0; 512 * 1024]); + } + + #[test] + fn ones() { + assert_sum_eq(&[]); + assert_sum_eq(&[1]); + assert_sum_eq(&[1, 1]); + assert_sum_eq(&[1; 100]); + assert_sum_eq(&[1; 1024]); + assert_sum_eq(&[1; 512 * 1024]); + } + + #[test] + fn random() { + let mut random = [0; 512 * 1024]; + rand::thread_rng().fill(&mut random[..]); + + assert_sum_eq(&random[..1]); + assert_sum_eq(&random[..100]); + assert_sum_eq(&random[..1024]); + assert_sum_eq(&random[..512 * 1024]); + } + + /// Example calculation from https://en.wikipedia.org/wiki/Adler-32. + #[test] + fn wiki() { + assert_sum_eq(b"Wikipedia"); + } + + fn assert_sum_eq(data: &[u8]) { + if let Some(update) = super::get_imp() { + let (a, b) = update(1, 0, data); + let left = u32::from(b) << 16 | u32::from(a); + let right = adler::adler32_slice(data); + + assert_eq!(left, right, "len({})", data.len()); + } + } +} |