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-rw-r--r--vendor/ahash-0.7.6/src/operations.rs330
1 files changed, 330 insertions, 0 deletions
diff --git a/vendor/ahash-0.7.6/src/operations.rs b/vendor/ahash-0.7.6/src/operations.rs
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+++ b/vendor/ahash-0.7.6/src/operations.rs
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+use crate::convert::*;
+
+/// This is a constant with a lot of special properties found by automated search.
+/// See the unit tests below. (Below are alternative values)
+#[cfg(all(target_feature = "ssse3", not(miri)))]
+const SHUFFLE_MASK: u128 = 0x020a0700_0c01030e_050f0d08_06090b04_u128;
+//const SHUFFLE_MASK: u128 = 0x000d0702_0a040301_05080f0c_0e0b0609_u128;
+//const SHUFFLE_MASK: u128 = 0x040A0700_030E0106_0D050F08_020B0C09_u128;
+
+#[inline(always)]
+pub(crate) const fn folded_multiply(s: u64, by: u64) -> u64 {
+ let result = (s as u128).wrapping_mul(by as u128);
+ ((result & 0xffff_ffff_ffff_ffff) as u64) ^ ((result >> 64) as u64)
+}
+
+
+/// Given a small (less than 8 byte slice) returns the same data stored in two u32s.
+/// (order of and non-duplication of bytes is NOT guaranteed)
+#[inline(always)]
+pub(crate) fn read_small(data: &[u8]) -> [u64; 2] {
+ debug_assert!(data.len() <= 8);
+ if data.len() >= 2 {
+ if data.len() >= 4 {
+ //len 4-8
+ [data.read_u32().0 as u64, data.read_last_u32() as u64]
+ } else {
+ //len 2-3
+ [data.read_u16().0 as u64, data[data.len() - 1] as u64]
+ }
+ } else {
+ if data.len() > 0 {
+ [data[0] as u64, data[0] as u64]
+ } else {
+ [0, 0]
+ }
+ }
+}
+
+#[inline(always)]
+pub(crate) fn shuffle(a: u128) -> u128 {
+ #[cfg(all(target_feature = "ssse3", not(miri)))]
+ {
+ #[cfg(target_arch = "x86")]
+ use core::arch::x86::*;
+ #[cfg(target_arch = "x86_64")]
+ use core::arch::x86_64::*;
+ use core::mem::transmute;
+ unsafe { transmute(_mm_shuffle_epi8(transmute(a), transmute(SHUFFLE_MASK))) }
+ }
+ #[cfg(not(all(target_feature = "ssse3", not(miri))))]
+ {
+ a.swap_bytes()
+ }
+}
+
+#[allow(unused)] //not used by fallback
+#[inline(always)]
+pub(crate) fn add_and_shuffle(a: u128, b: u128) -> u128 {
+ let sum = add_by_64s(a.convert(), b.convert());
+ shuffle(sum.convert())
+}
+
+#[allow(unused)] //not used by fallbac
+#[inline(always)]
+pub(crate) fn shuffle_and_add(base: u128, to_add: u128) -> u128 {
+ let shuffled: [u64; 2] = shuffle(base).convert();
+ add_by_64s(shuffled, to_add.convert()).convert()
+}
+
+#[cfg(all(any(target_arch = "x86", target_arch = "x86_64"), target_feature = "sse2", not(miri)))]
+#[inline(always)]
+pub(crate) fn add_by_64s(a: [u64; 2], b: [u64; 2]) -> [u64; 2] {
+ use core::mem::transmute;
+ unsafe {
+ #[cfg(target_arch = "x86")]
+ use core::arch::x86::*;
+ #[cfg(target_arch = "x86_64")]
+ use core::arch::x86_64::*;
+ transmute(_mm_add_epi64(transmute(a), transmute(b)))
+ }
+}
+
+#[cfg(not(all(any(target_arch = "x86", target_arch = "x86_64"), target_feature = "sse2", not(miri))))]
+#[inline(always)]
+pub(crate) fn add_by_64s(a: [u64; 2], b: [u64; 2]) -> [u64; 2] {
+ [a[0].wrapping_add(b[0]), a[1].wrapping_add(b[1])]
+}
+
+#[cfg(all(any(target_arch = "x86", target_arch = "x86_64"), target_feature = "aes", not(miri)))]
+#[allow(unused)]
+#[inline(always)]
+pub(crate) fn aesenc(value: u128, xor: u128) -> u128 {
+ #[cfg(target_arch = "x86")]
+ use core::arch::x86::*;
+ #[cfg(target_arch = "x86_64")]
+ use core::arch::x86_64::*;
+ use core::mem::transmute;
+ unsafe {
+ let value = transmute(value);
+ transmute(_mm_aesenc_si128(value, transmute(xor)))
+ }
+}
+
+#[cfg(all(any(target_arch = "arm", target_arch = "aarch64"), target_feature = "crypto", not(miri), feature = "stdsimd"))]
+#[allow(unused)]
+#[inline(always)]
+pub(crate) fn aesenc(value: u128, xor: u128) -> u128 {
+ #[cfg(target_arch = "arm")]
+ use core::arch::arm::*;
+ #[cfg(target_arch = "aarch64")]
+ use core::arch::aarch64::*;
+ use core::mem::transmute;
+ unsafe {
+ let value = transmute(value);
+ transmute(vaesmcq_u8(vaeseq_u8(value, transmute(xor))))
+ }
+}
+
+#[cfg(all(any(target_arch = "x86", target_arch = "x86_64"), target_feature = "aes", not(miri)))]
+#[allow(unused)]
+#[inline(always)]
+pub(crate) fn aesdec(value: u128, xor: u128) -> u128 {
+ #[cfg(target_arch = "x86")]
+ use core::arch::x86::*;
+ #[cfg(target_arch = "x86_64")]
+ use core::arch::x86_64::*;
+ use core::mem::transmute;
+ unsafe {
+ let value = transmute(value);
+ transmute(_mm_aesdec_si128(value, transmute(xor)))
+ }
+}
+
+#[cfg(all(any(target_arch = "arm", target_arch = "aarch64"), target_feature = "crypto", not(miri), feature = "stdsimd"))]
+#[allow(unused)]
+#[inline(always)]
+pub(crate) fn aesdec(value: u128, xor: u128) -> u128 {
+ #[cfg(target_arch = "arm")]
+ use core::arch::arm::*;
+ #[cfg(target_arch = "aarch64")]
+ use core::arch::aarch64::*;
+ use core::mem::transmute;
+ unsafe {
+ let value = transmute(value);
+ transmute(vaesimcq_u8(vaesdq_u8(value, transmute(xor))))
+ }
+}
+
+#[cfg(test)]
+mod test {
+ use super::*;
+ use crate::convert::Convert;
+
+ // This is code to search for the shuffle constant
+ //
+ //thread_local! { static MASK: Cell<u128> = Cell::new(0); }
+ //
+ // fn shuffle(a: u128) -> u128 {
+ // use std::intrinsics::transmute;
+ // #[cfg(target_arch = "x86")]
+ // use core::arch::x86::*;
+ // #[cfg(target_arch = "x86_64")]
+ // use core::arch::x86_64::*;
+ // MASK.with(|mask| {
+ // unsafe { transmute(_mm_shuffle_epi8(transmute(a), transmute(mask.get()))) }
+ // })
+ // }
+ //
+ // #[test]
+ // fn find_shuffle() {
+ // use rand::prelude::*;
+ // use SliceRandom;
+ // use std::panic;
+ // use std::io::Write;
+ //
+ // let mut value: [u8; 16] = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 ,13, 14, 15];
+ // let mut rand = thread_rng();
+ // let mut successful_list = HashMap::new();
+ // for _attempt in 0..10000000 {
+ // rand.shuffle(&mut value);
+ // let test_val = value.convert();
+ // MASK.with(|mask| {
+ // mask.set(test_val);
+ // });
+ // if let Ok(successful) = panic::catch_unwind(|| {
+ // test_shuffle_does_not_collide_with_aes();
+ // test_shuffle_moves_high_bits();
+ // test_shuffle_moves_every_value();
+ // //test_shuffle_does_not_loop();
+ // value
+ // }) {
+ // let successful: u128 = successful.convert();
+ // successful_list.insert(successful, iters_before_loop());
+ // }
+ // }
+ // let write_file = File::create("/tmp/output").unwrap();
+ // let mut writer = BufWriter::new(&write_file);
+ //
+ // for success in successful_list {
+ // writeln!(writer, "Found successful: {:x?} - {:?}", success.0, success.1);
+ // }
+ // }
+ //
+ // fn iters_before_loop() -> u32 {
+ // let numbered = 0x00112233_44556677_8899AABB_CCDDEEFF;
+ // let mut shuffled = shuffle(numbered);
+ // let mut count = 0;
+ // loop {
+ // // println!("{:>16x}", shuffled);
+ // if numbered == shuffled {
+ // break;
+ // }
+ // count += 1;
+ // shuffled = shuffle(shuffled);
+ // }
+ // count
+ // }
+
+ #[cfg(all(
+ any(target_arch = "x86", target_arch = "x86_64"),
+ target_feature = "ssse3",
+ target_feature = "aes",
+ not(miri)
+ ))]
+ #[test]
+ fn test_shuffle_does_not_collide_with_aes() {
+ let mut value: [u8; 16] = [0; 16];
+ let zero_mask_enc = aesenc(0, 0);
+ let zero_mask_dec = aesdec(0, 0);
+ for index in 0..16 {
+ value[index] = 1;
+ let excluded_positions_enc: [u8; 16] = aesenc(value.convert(), zero_mask_enc).convert();
+ let excluded_positions_dec: [u8; 16] = aesdec(value.convert(), zero_mask_dec).convert();
+ let actual_location: [u8; 16] = shuffle(value.convert()).convert();
+ for pos in 0..16 {
+ if actual_location[pos] != 0 {
+ assert_eq!(
+ 0, excluded_positions_enc[pos],
+ "Forward Overlap between {:?} and {:?} at {}",
+ excluded_positions_enc, actual_location, index
+ );
+ assert_eq!(
+ 0, excluded_positions_dec[pos],
+ "Reverse Overlap between {:?} and {:?} at {}",
+ excluded_positions_dec, actual_location, index
+ );
+ }
+ }
+ value[index] = 0;
+ }
+ }
+
+ #[test]
+ fn test_shuffle_contains_each_value() {
+ let value: [u8; 16] = 0x00010203_04050607_08090A0B_0C0D0E0F_u128.convert();
+ let shuffled: [u8; 16] = shuffle(value.convert()).convert();
+ for index in 0..16_u8 {
+ assert!(shuffled.contains(&index), "Value is missing {}", index);
+ }
+ }
+
+ #[test]
+ fn test_shuffle_moves_every_value() {
+ let mut value: [u8; 16] = [0; 16];
+ for index in 0..16 {
+ value[index] = 1;
+ let shuffled: [u8; 16] = shuffle(value.convert()).convert();
+ assert_eq!(0, shuffled[index], "Value is not moved {}", index);
+ value[index] = 0;
+ }
+ }
+
+ #[test]
+ fn test_shuffle_moves_high_bits() {
+ assert!(
+ shuffle(1) > (1_u128 << 80),
+ "Low bits must be moved to other half {:?} -> {:?}",
+ 0,
+ shuffle(1)
+ );
+
+ assert!(
+ shuffle(1_u128 << 58) >= (1_u128 << 64),
+ "High bits must be moved to other half {:?} -> {:?}",
+ 7,
+ shuffle(1_u128 << 58)
+ );
+ assert!(
+ shuffle(1_u128 << 58) < (1_u128 << 112),
+ "High bits must not remain high {:?} -> {:?}",
+ 7,
+ shuffle(1_u128 << 58)
+ );
+ assert!(
+ shuffle(1_u128 << 64) < (1_u128 << 64),
+ "Low bits must be moved to other half {:?} -> {:?}",
+ 8,
+ shuffle(1_u128 << 64)
+ );
+ assert!(
+ shuffle(1_u128 << 64) >= (1_u128 << 16),
+ "Low bits must not remain low {:?} -> {:?}",
+ 8,
+ shuffle(1_u128 << 64)
+ );
+
+ assert!(
+ shuffle(1_u128 << 120) < (1_u128 << 50),
+ "High bits must be moved to low half {:?} -> {:?}",
+ 15,
+ shuffle(1_u128 << 120)
+ );
+ }
+
+ #[cfg(all(
+ any(target_arch = "x86", target_arch = "x86_64"),
+ target_feature = "ssse3",
+ not(miri)
+ ))]
+ #[test]
+ fn test_shuffle_does_not_loop() {
+ let numbered = 0x00112233_44556677_8899AABB_CCDDEEFF;
+ let mut shuffled = shuffle(numbered);
+ for count in 0..100 {
+ // println!("{:>16x}", shuffled);
+ assert_ne!(numbered, shuffled, "Equal after {} vs {:x}", count, shuffled);
+ shuffled = shuffle(shuffled);
+ }
+ }
+}
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