Add x86 intrinsics support for sha2-512 (#312)

sha2/src/sha512.rs

@@ -231,10 +231,17 @@ cfg_if::cfg_if! {
     if #[cfg(feature = "force-soft")] {
         mod soft;
         use soft::compress;
-    } else if #[cfg(all(feature = "asm", any(target_arch = "x86", target_arch = "x86_64")))] {
-        fn compress(state: &mut [u64; 8], blocks: &[[u8; 128]]) {
-            sha2_asm::compress512(state, blocks);
+    } else if #[cfg(any(target_arch = "x86", target_arch = "x86_64"))] {
+        #[cfg(not(feature = "asm"))]
+        mod soft;
+        #[cfg(feature = "asm")]
+        mod soft {
+            pub(crate) fn compress(state: &mut [u64; 8], blocks: &[[u8; 128]]) {
+                sha2_asm::compress512(state, blocks);
+            }
         }
+        mod x86;
+        use x86::compress;
     } else {
         mod soft;
         use soft::compress;

sha2/src/sha512/x86.rs

@@ -0,0 +1,352 @@
+//! SHA-512 `x86`/`x86_64` backend
+
+#![allow(clippy::many_single_char_names)]
+
+use core::mem::size_of;
+
+#[cfg(target_arch = "x86")]
+use core::arch::x86::*;
+#[cfg(target_arch = "x86_64")]
+use core::arch::x86_64::*;
+
+use crate::consts::K64;
+
+cpufeatures::new!(avx2_cpuid, "avx2");
+
+pub fn compress(state: &mut [u64; 8], blocks: &[[u8; 128]]) {
+    // TODO: Replace with https://github.com/rust-lang/rfcs/pull/2725
+    // after stabilization
+    if avx2_cpuid::get() {
+        unsafe {
+            sha512_compress_x86_64_avx2(state, blocks);
+        }
+    } else {
+        super::soft::compress(state, blocks);
+    }
+}
+
+#[target_feature(enable = "avx2")]
+unsafe fn sha512_compress_x86_64_avx2(state: &mut [u64; 8], blocks: &[[u8; 128]]) {
+    let mut start_block = 0;
+
+    if blocks.len() & 0b1 != 0 {
+        sha512_compress_x86_64_avx(state, &blocks[0]);
+        start_block += 1;
+    }
+
+    let mut ms: MsgSchedule = Default::default();
+    let mut t2: RoundStates = [0u64; SHA512_ROUNDS_NUM];
+    let mut x = [_mm256_setzero_si256(); 8];
+
+    for i in (start_block..blocks.len()).step_by(2) {
+        load_data_avx2(&mut x, &mut ms, &mut t2, blocks.as_ptr().add(i) as *const _);
+
+        // First block
+        let mut current_state = *state;
+        rounds_0_63_avx2(&mut current_state, &mut x, &mut ms, &mut t2);
+        rounds_64_79(&mut current_state, &ms);
+        accumulate_state(state, &current_state);
+
+        // Second block
+        current_state = *state;
+        process_second_block(&mut current_state, &t2);
+        accumulate_state(state, &current_state);
+    }
+}
+
+#[inline(always)]
+unsafe fn sha512_compress_x86_64_avx(state: &mut [u64; 8], block: &[u8; 128]) {
+    let mut ms = Default::default();
+    let mut x = [_mm_setzero_si128(); 8];
+
+    // Reduced to single iteration
+    let mut current_state = *state;
+    load_data_avx(&mut x, &mut ms, block.as_ptr() as *const _);
+    rounds_0_63_avx(&mut current_state, &mut x, &mut ms);
+    rounds_64_79(&mut current_state, &ms);
+    accumulate_state(state, &current_state);
+}
+
+#[inline(always)]
+unsafe fn load_data_avx(x: &mut [__m128i; 8], ms: &mut MsgSchedule, data: *const __m128i) {
+    #[allow(non_snake_case)]
+    let MASK = _mm_setr_epi32(0x04050607, 0x00010203, 0x0c0d0e0f, 0x08090a0b);
+
+    macro_rules! unrolled_iterations {
+        ($($i:literal),*) => {$(
+            x[$i] = _mm_loadu_si128(data.add($i) as *const _);
+            x[$i] = _mm_shuffle_epi8(x[$i], MASK);
+
+            let y = _mm_add_epi64(
+                x[$i],
+                _mm_loadu_si128(&K64[2 * $i] as *const u64 as *const _),
+            );
+
+            _mm_store_si128(&mut ms[2 * $i] as *mut u64 as *mut _, y);
+        )*};
+    }
+
+    unrolled_iterations!(0, 1, 2, 3, 4, 5, 6, 7);
+}
+
+#[inline(always)]
+unsafe fn load_data_avx2(
+    x: &mut [__m256i; 8],
+    ms: &mut MsgSchedule,
+    t2: &mut RoundStates,
+    data: *const __m128i,
+) {
+    #[allow(non_snake_case)]
+    let MASK = _mm256_set_epi64x(
+        0x0809_0A0B_0C0D_0E0F_i64,
+        0x0001_0203_0405_0607_i64,
+        0x0809_0A0B_0C0D_0E0F_i64,
+        0x0001_0203_0405_0607_i64,
+    );
+
+    macro_rules! unrolled_iterations {
+        ($($i:literal),*) => {$(
+            x[$i] = _mm256_insertf128_si256(x[$i], _mm_loadu_si128(data.add($i) as *const _), 1);
+            x[$i] = _mm256_insertf128_si256(x[$i], _mm_loadu_si128(data.add($i + 1) as *const _), 0);
+
+            x[$i] = _mm256_shuffle_epi8(x[$i], MASK);
+
+            let t = _mm_loadu_si128(K64.as_ptr().add($i * 2) as *const u64 as *const _);
+            let y = _mm256_add_epi64(x[$i], _mm256_set_m128i(t, t));
+
+            _mm_store_si128(
+                &mut ms[2 * $i] as *mut u64 as *mut _,
+                _mm256_extracti128_si256(y, 0),
+            );
+            _mm_store_si128(
+                &mut t2[2 * $i] as *mut u64 as *mut _,
+                _mm256_extracti128_si256(y, 1),
+            );
+        )*};
+    }
+
+    unrolled_iterations!(0, 1, 2, 3, 4, 5, 6, 7);
+}
+
+#[inline(always)]
+unsafe fn rounds_0_63_avx(current_state: &mut State, x: &mut [__m128i; 8], ms: &mut MsgSchedule) {
+    let mut k64_idx: usize = SHA512_BLOCK_WORDS_NUM;
+
+    for _ in 0..4 {
+        for j in 0..8 {
+            let k64 = _mm_loadu_si128(&K64[k64_idx] as *const u64 as *const _);
+            let y = sha512_update_x_avx(x, k64);
+
+            sha_round(current_state, ms[2 * j]);
+            sha_round(current_state, ms[2 * j + 1]);
+
+            _mm_store_si128(&mut ms[2 * j] as *const u64 as *mut _, y);
+            k64_idx += 2;
+        }
+    }
+}
+
+#[inline(always)]
+unsafe fn rounds_0_63_avx2(
+    current_state: &mut State,
+    x: &mut [__m256i; 8],
+    ms: &mut MsgSchedule,
+    t2: &mut RoundStates,
+) {
+    let mut k64x4_idx: usize = SHA512_BLOCK_WORDS_NUM;
+
+    for i in 1..5 {
+        for j in 0..8 {
+            let t = _mm_loadu_si128(K64.as_ptr().add(k64x4_idx) as *const u64 as *const _);
+            let y = sha512_update_x_avx2(x, _mm256_set_m128i(t, t));
+
+            sha_round(current_state, ms[2 * j]);
+            sha_round(current_state, ms[2 * j + 1]);
+
+            _mm_store_si128(
+                &mut ms[2 * j] as *mut u64 as *mut _,
+                _mm256_extracti128_si256(y, 0),
+            );
+            _mm_store_si128(
+                &mut t2[(16 * i) + 2 * j] as *mut u64 as *mut _,
+                _mm256_extracti128_si256(y, 1),
+            );
+
+            k64x4_idx += 2;
+        }
+    }
+}
+
+#[inline(always)]
+unsafe fn rounds_64_79(current_state: &mut State, ms: &MsgSchedule) {
+    for i in 64..80 {
+        sha_round(current_state, ms[i & 0xf]);
+    }
+}
+
+#[inline(always)]
+unsafe fn process_second_block(current_state: &mut State, t2: &RoundStates) {
+    for t2 in t2.iter() {
+        sha_round(current_state, *t2);
+    }
+}
+
+#[inline(always)]
+unsafe fn sha_round(s: &mut State, x: u64) {
+    macro_rules! big_sigma0 {
+        ($a:expr) => {
+            $a.rotate_right(28) ^ $a.rotate_right(34) ^ $a.rotate_right(39)
+        };
+    }
+    macro_rules! big_sigma1 {
+        ($a:expr) => {
+            $a.rotate_right(14) ^ $a.rotate_right(18) ^ $a.rotate_right(41)
+        };
+    }
+    macro_rules! bool3ary_202 {
+        ($a:expr, $b:expr, $c:expr) => {
+            $c ^ ($a & ($b ^ $c))
+        };
+    } // Choose, MD5F, SHA1C
+    macro_rules! bool3ary_232 {
+        ($a:expr, $b:expr, $c:expr) => {
+            ($a & $b) ^ ($a & $c) ^ ($b & $c)
+        };
+    } // Majority, SHA1M
+
+    macro_rules! rotate_state {
+        ($s:ident) => {{
+            let tmp = $s[7];
+            $s[7] = $s[6];
+            $s[6] = $s[5];
+            $s[5] = $s[4];
+            $s[4] = $s[3];
+            $s[3] = $s[2];
+            $s[2] = $s[1];
+            $s[1] = $s[0];
+            $s[0] = tmp;
+        }};
+    }
+
+    let t = x
+        .wrapping_add(s[7])
+        .wrapping_add(big_sigma1!(s[4]))
+        .wrapping_add(bool3ary_202!(s[4], s[5], s[6]));
+
+    s[7] = t
+        .wrapping_add(big_sigma0!(s[0]))
+        .wrapping_add(bool3ary_232!(s[0], s[1], s[2]));
+    s[3] = s[3].wrapping_add(t);
+
+    rotate_state!(s);
+}
+
+#[inline(always)]
+unsafe fn accumulate_state(dst: &mut State, src: &State) {
+    for i in 0..SHA512_HASH_WORDS_NUM {
+        dst[i] = dst[i].wrapping_add(src[i]);
+    }
+}
+
+macro_rules! fn_sha512_update_x {
+    ($name:ident, $ty:ident, {
+        ADD64 = $ADD64:ident,
+        ALIGNR8 = $ALIGNR8:ident,
+        SRL64 = $SRL64:ident,
+        SLL64 = $SLL64:ident,
+        XOR = $XOR:ident,
+    }) => {
+        unsafe fn $name(x: &mut [$ty; 8], k64: $ty) -> $ty {
+            // q[2:1]
+            let mut t0 = $ALIGNR8(x[1], x[0], 8);
+            // q[10:9]
+            let mut t3 = $ALIGNR8(x[5], x[4], 8);
+            // q[2:1] >> s0[0]
+            let mut t2 = $SRL64(t0, 1);
+            // q[1:0] + q[10:9]
+            x[0] = $ADD64(x[0], t3);
+            // q[2:1] >> s0[2]
+            t3 = $SRL64(t0, 7);
+            // q[2:1] << (64 - s0[1])
+            let mut t1 = $SLL64(t0, 64 - 8);
+            // (q[2:1] >> s0[2]) ^
+            // (q[2:1] >> s0[0])
+            t0 = $XOR(t3, t2);
+            // q[2:1] >> s0[1]
+            t2 = $SRL64(t2, 8 - 1);
+            // (q[2:1] >> s0[2]) ^
+            // (q[2:1] >> s0[0]) ^
+            // q[2:1] << (64 - s0[1])
+            t0 = $XOR(t0, t1);
+            // q[2:1] << (64 - s0[0])
+            t1 = $SLL64(t1, 8 - 1);
+            // sigma1(q[2:1])
+            t0 = $XOR(t0, t2);
+            t0 = $XOR(t0, t1);
+            // q[15:14] >> s1[2]
+            t3 = $SRL64(x[7], 6);
+            // q[15:14] >> (64 - s1[1])
+            t2 = $SLL64(x[7], 64 - 61);
+            // q[1:0] + sigma0(q[2:1])
+            x[0] = $ADD64(x[0], t0);
+            // q[15:14] >> s1[0]
+            t1 = $SRL64(x[7], 19);
+            // q[15:14] >> s1[2] ^
+            // q[15:14] >> (64 - s1[1])
+            t3 = $XOR(t3, t2);
+            // q[15:14] >> (64 - s1[0])
+            t2 = $SLL64(t2, 61 - 19);
+            // q[15:14] >> s1[2] ^
+            // q[15:14] >> (64 - s1[1] ^
+            // q[15:14] >> s1[0]
+            t3 = $XOR(t3, t1);
+            // q[15:14] >> s1[1]
+            t1 = $SRL64(t1, 61 - 19);
+            // sigma1(q[15:14])
+            t3 = $XOR(t3, t2);
+            t3 = $XOR(t3, t1);
+
+            // q[1:0] + q[10:9] + sigma1(q[15:14]) + sigma0(q[2:1])
+            x[0] = $ADD64(x[0], t3);
+
+            // rotate
+            let temp = x[0];
+            x[0] = x[1];
+            x[1] = x[2];
+            x[2] = x[3];
+            x[3] = x[4];
+            x[4] = x[5];
+            x[5] = x[6];
+            x[6] = x[7];
+            x[7] = temp;
+
+            $ADD64(x[7], k64)
+        }
+    };
+}
+
+fn_sha512_update_x!(sha512_update_x_avx, __m128i, {
+        ADD64 = _mm_add_epi64,
+        ALIGNR8 = _mm_alignr_epi8,
+        SRL64 = _mm_srli_epi64,
+        SLL64 = _mm_slli_epi64,
+        XOR = _mm_xor_si128,
+});
+
+fn_sha512_update_x!(sha512_update_x_avx2, __m256i, {
+        ADD64 = _mm256_add_epi64,
+        ALIGNR8 = _mm256_alignr_epi8,
+        SRL64 = _mm256_srli_epi64,
+        SLL64 = _mm256_slli_epi64,
+        XOR = _mm256_xor_si256,
+});
+
+type State = [u64; SHA512_HASH_WORDS_NUM];
+type MsgSchedule = [u64; SHA512_BLOCK_WORDS_NUM];
+type RoundStates = [u64; SHA512_ROUNDS_NUM];
+
+const SHA512_BLOCK_BYTE_LEN: usize = 128;
+const SHA512_ROUNDS_NUM: usize = 80;
+const SHA512_HASH_BYTE_LEN: usize = 64;
+const SHA512_HASH_WORDS_NUM: usize = SHA512_HASH_BYTE_LEN / size_of::<u64>();
+const SHA512_BLOCK_WORDS_NUM: usize = SHA512_BLOCK_BYTE_LEN / size_of::<u64>();