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// Copyright 2016 Mozilla Foundation. See the COPYRIGHT
// file at the top-level directory of this distribution.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
// It's assumed that in due course Rust will have explicit SIMD but will not
// be good at run-time selection of SIMD vs. no-SIMD. In such a future,
// x86_64 will always use SSE2 and 32-bit x86 will use SSE2 when compiled with
// a Mozilla-shipped rustc. SIMD support and especially detection on ARM is a
// mess. Under the circumstances, it seems to make sense to optimize the ALU
// case for ARMv7 rather than x86. Annoyingly, I was unable to get useful
// numbers of the actual ARMv7 CPU I have access to, because (thermal?)
// throttling kept interfering. Since Raspberry Pi 3 (ARMv8 core but running
// ARMv7 code) produced reproducible performance numbers, that's the ARM
// computer that this code ended up being optimized for in the ALU case.
// Less popular CPU architectures simply get the approach that was chosen based
// on Raspberry Pi 3 measurements. The UTF-16 and UTF-8 ALU cases take
// different approaches based on benchmarking on Raspberry Pi 3.
#[cfg(all(
feature = "simd-accel",
any(
target_feature = "sse2",
all(target_endian = "little", target_arch = "aarch64"),
all(target_endian = "little", target_feature = "neon")
)
))]
use simd_funcs::*;
cfg_if! {
if #[cfg(feature = "simd-accel")] {
#[allow(unused_imports)]
use ::std::intrinsics::unlikely;
#[allow(unused_imports)]
use ::std::intrinsics::likely;
} else {
#[allow(dead_code)]
#[inline(always)]
// Unsafe to match the intrinsic, which is needlessly unsafe.
unsafe fn unlikely(b: bool) -> bool {
b
}
#[allow(dead_code)]
#[inline(always)]
// Unsafe to match the intrinsic, which is needlessly unsafe.
unsafe fn likely(b: bool) -> bool {
b
}
}
}
// `as` truncates, so works on 32-bit, too.
#[allow(dead_code)]
pub const ASCII_MASK: usize = 0x8080_8080_8080_8080u64 as usize;
// `as` truncates, so works on 32-bit, too.
#[allow(dead_code)]
pub const BASIC_LATIN_MASK: usize = 0xFF80_FF80_FF80_FF80u64 as usize;
#[allow(unused_macros)]
macro_rules! ascii_naive {
($name:ident, $src_unit:ty, $dst_unit:ty) => {
#[inline(always)]
pub unsafe fn $name(
src: *const $src_unit,
dst: *mut $dst_unit,
len: usize,
) -> Option<($src_unit, usize)> {
// Yes, manually omitting the bound check here matters
// a lot for perf.
for i in 0..len {
let code_unit = *(src.add(i));
if code_unit > 127 {
return Some((code_unit, i));
}
*(dst.add(i)) = code_unit as $dst_unit;
}
return None;
}
};
}
#[allow(unused_macros)]
macro_rules! ascii_alu {
($name:ident,
$src_unit:ty,
$dst_unit:ty,
$stride_fn:ident) => {
#[cfg_attr(feature = "cargo-clippy", allow(never_loop, cast_ptr_alignment))]
#[inline(always)]
pub unsafe fn $name(
src: *const $src_unit,
dst: *mut $dst_unit,
len: usize,
) -> Option<($src_unit, usize)> {
let mut offset = 0usize;
// This loop is only broken out of as a `goto` forward
loop {
let mut until_alignment = {
// Check if the other unit aligns if we move the narrower unit
// to alignment.
// if ::std::mem::size_of::<$src_unit>() == ::std::mem::size_of::<$dst_unit>() {
// ascii_to_ascii
let src_alignment = (src as usize) & ALU_ALIGNMENT_MASK;
let dst_alignment = (dst as usize) & ALU_ALIGNMENT_MASK;
if src_alignment != dst_alignment {
break;
}
(ALU_ALIGNMENT - src_alignment) & ALU_ALIGNMENT_MASK
// } else if ::std::mem::size_of::<$src_unit>() < ::std::mem::size_of::<$dst_unit>() {
// ascii_to_basic_latin
// let src_until_alignment = (ALIGNMENT - ((src as usize) & ALIGNMENT_MASK)) & ALIGNMENT_MASK;
// if (dst.add(src_until_alignment) as usize) & ALIGNMENT_MASK != 0 {
// break;
// }
// src_until_alignment
// } else {
// basic_latin_to_ascii
// let dst_until_alignment = (ALIGNMENT - ((dst as usize) & ALIGNMENT_MASK)) & ALIGNMENT_MASK;
// if (src.add(dst_until_alignment) as usize) & ALIGNMENT_MASK != 0 {
// break;
// }
// dst_until_alignment
// }
};
if until_alignment + ALU_STRIDE_SIZE <= len {
// Moving pointers to alignment seems to be a pessimization on
// x86_64 for operations that have UTF-16 as the internal
// Unicode representation. However, since it seems to be a win
// on ARM (tested ARMv7 code running on ARMv8 [rpi3]), except
// mixed results when encoding from UTF-16 and since x86 and
// x86_64 should be using SSE2 in due course, keeping the move
// to alignment here. It would be good to test on more ARM CPUs
// and on real MIPS and POWER hardware.
while until_alignment != 0 {
let code_unit = *(src.add(offset));
if code_unit > 127 {
return Some((code_unit, offset));
}
*(dst.add(offset)) = code_unit as $dst_unit;
offset += 1;
until_alignment -= 1;
}
let len_minus_stride = len - ALU_STRIDE_SIZE;
loop {
if let Some(num_ascii) = $stride_fn(
src.add(offset) as *const usize,
dst.add(offset) as *mut usize,
) {
offset += num_ascii;
return Some((*(src.add(offset)), offset));
}
offset += ALU_STRIDE_SIZE;
if offset > len_minus_stride {
break;
}
}
}
break;
}
while offset < len {
let code_unit = *(src.add(offset));
if code_unit > 127 {
return Some((code_unit, offset));
}
*(dst.add(offset)) = code_unit as $dst_unit;
offset += 1;
}
None
}
};
}
#[allow(unused_macros)]
macro_rules! basic_latin_alu {
($name:ident,
$src_unit:ty,
$dst_unit:ty,
$stride_fn:ident) => {
#[cfg_attr(
feature = "cargo-clippy",
allow(never_loop, cast_ptr_alignment, cast_lossless)
)]
#[inline(always)]
pub unsafe fn $name(
src: *const $src_unit,
dst: *mut $dst_unit,
len: usize,
) -> Option<($src_unit, usize)> {
let mut offset = 0usize;
// This loop is only broken out of as a `goto` forward
loop {
let mut until_alignment = {
// Check if the other unit aligns if we move the narrower unit
// to alignment.
// if ::std::mem::size_of::<$src_unit>() == ::std::mem::size_of::<$dst_unit>() {
// ascii_to_ascii
// let src_alignment = (src as usize) & ALIGNMENT_MASK;
// let dst_alignment = (dst as usize) & ALIGNMENT_MASK;
// if src_alignment != dst_alignment {
// break;
// }
// (ALIGNMENT - src_alignment) & ALIGNMENT_MASK
// } else
if ::std::mem::size_of::<$src_unit>() < ::std::mem::size_of::<$dst_unit>() {
// ascii_to_basic_latin
let src_until_alignment = (ALU_ALIGNMENT
- ((src as usize) & ALU_ALIGNMENT_MASK))
& ALU_ALIGNMENT_MASK;
if (dst.add(src_until_alignment) as usize) & ALU_ALIGNMENT_MASK != 0 {
break;
}
src_until_alignment
} else {
// basic_latin_to_ascii
let dst_until_alignment = (ALU_ALIGNMENT
- ((dst as usize) & ALU_ALIGNMENT_MASK))
& ALU_ALIGNMENT_MASK;
if (src.add(dst_until_alignment) as usize) & ALU_ALIGNMENT_MASK != 0 {
break;
}
dst_until_alignment
}
};
if until_alignment + ALU_STRIDE_SIZE <= len {
// Moving pointers to alignment seems to be a pessimization on
// x86_64 for operations that have UTF-16 as the internal
// Unicode representation. However, since it seems to be a win
// on ARM (tested ARMv7 code running on ARMv8 [rpi3]), except
// mixed results when encoding from UTF-16 and since x86 and
// x86_64 should be using SSE2 in due course, keeping the move
// to alignment here. It would be good to test on more ARM CPUs
// and on real MIPS and POWER hardware.
while until_alignment != 0 {
let code_unit = *(src.add(offset));
if code_unit > 127 {
return Some((code_unit, offset));
}
*(dst.add(offset)) = code_unit as $dst_unit;
offset += 1;
until_alignment -= 1;
}
let len_minus_stride = len - ALU_STRIDE_SIZE;
loop {
if !$stride_fn(
src.add(offset) as *const usize,
dst.add(offset) as *mut usize,
) {
break;
}
offset += ALU_STRIDE_SIZE;
if offset > len_minus_stride {
break;
}
}
}
break;
}
while offset < len {
let code_unit = *(src.add(offset));
if code_unit > 127 {
return Some((code_unit, offset));
}
*(dst.add(offset)) = code_unit as $dst_unit;
offset += 1;
}
None
}
};
}
#[allow(unused_macros)]
macro_rules! latin1_alu {
($name:ident, $src_unit:ty, $dst_unit:ty, $stride_fn:ident) => {
#[cfg_attr(
feature = "cargo-clippy",
allow(never_loop, cast_ptr_alignment, cast_lossless)
)]
#[inline(always)]
pub unsafe fn $name(src: *const $src_unit, dst: *mut $dst_unit, len: usize) {
let mut offset = 0usize;
// This loop is only broken out of as a `goto` forward
loop {
let mut until_alignment = {
if ::std::mem::size_of::<$src_unit>() < ::std::mem::size_of::<$dst_unit>() {
// unpack
let src_until_alignment = (ALU_ALIGNMENT
- ((src as usize) & ALU_ALIGNMENT_MASK))
& ALU_ALIGNMENT_MASK;
if (dst.add(src_until_alignment) as usize) & ALU_ALIGNMENT_MASK != 0 {
break;
}
src_until_alignment
} else {
// pack
let dst_until_alignment = (ALU_ALIGNMENT
- ((dst as usize) & ALU_ALIGNMENT_MASK))
& ALU_ALIGNMENT_MASK;
if (src.add(dst_until_alignment) as usize) & ALU_ALIGNMENT_MASK != 0 {
break;
}
dst_until_alignment
}
};
if until_alignment + ALU_STRIDE_SIZE <= len {
while until_alignment != 0 {
let code_unit = *(src.add(offset));
*(dst.add(offset)) = code_unit as $dst_unit;
offset += 1;
until_alignment -= 1;
}
let len_minus_stride = len - ALU_STRIDE_SIZE;
loop {
$stride_fn(
src.add(offset) as *const usize,
dst.add(offset) as *mut usize,
);
offset += ALU_STRIDE_SIZE;
if offset > len_minus_stride {
break;
}
}
}
break;
}
while offset < len {
let code_unit = *(src.add(offset));
*(dst.add(offset)) = code_unit as $dst_unit;
offset += 1;
}
}
};
}
#[allow(unused_macros)]
macro_rules! ascii_simd_check_align {
(
$name:ident,
$src_unit:ty,
$dst_unit:ty,
$stride_both_aligned:ident,
$stride_src_aligned:ident,
$stride_dst_aligned:ident,
$stride_neither_aligned:ident
) => {
#[inline(always)]
pub unsafe fn $name(
src: *const $src_unit,
dst: *mut $dst_unit,
len: usize,
) -> Option<($src_unit, usize)> {
let mut offset = 0usize;
if SIMD_STRIDE_SIZE <= len {
let len_minus_stride = len - SIMD_STRIDE_SIZE;
// XXX Should we first process one stride unconditionally as unaligned to
// avoid the cost of the branchiness below if the first stride fails anyway?
// XXX Should we just use unaligned SSE2 access unconditionally? It seems that
// on Haswell, it would make sense to just use unaligned and not bother
// checking. Need to benchmark older architectures before deciding.
let dst_masked = (dst as usize) & SIMD_ALIGNMENT_MASK;
if ((src as usize) & SIMD_ALIGNMENT_MASK) == 0 {
if dst_masked == 0 {
loop {
if !$stride_both_aligned(src.add(offset), dst.add(offset)) {
break;
}
offset += SIMD_STRIDE_SIZE;
if offset > len_minus_stride {
break;
}
}
} else {
loop {
if !$stride_src_aligned(src.add(offset), dst.add(offset)) {
break;
}
offset += SIMD_STRIDE_SIZE;
if offset > len_minus_stride {
break;
}
}
}
} else {
if dst_masked == 0 {
loop {
if !$stride_dst_aligned(src.add(offset), dst.add(offset)) {
break;
}
offset += SIMD_STRIDE_SIZE;
if offset > len_minus_stride {
break;
}
}
} else {
loop {
if !$stride_neither_aligned(src.add(offset), dst.add(offset)) {
break;
}
offset += SIMD_STRIDE_SIZE;
if offset > len_minus_stride {
break;
}
}
}
}
}
while offset < len {
let code_unit = *(src.add(offset));
if code_unit > 127 {
return Some((code_unit, offset));
}
*(dst.add(offset)) = code_unit as $dst_unit;
offset += 1;
}
None
}
};
}
#[allow(unused_macros)]
macro_rules! ascii_simd_check_align_unrolled {
(
$name:ident,
$src_unit:ty,
$dst_unit:ty,
$stride_both_aligned:ident,
$stride_src_aligned:ident,
$stride_neither_aligned:ident,
$double_stride_both_aligned:ident,
$double_stride_src_aligned:ident
) => {
#[inline(always)]
pub unsafe fn $name(
src: *const $src_unit,
dst: *mut $dst_unit,
len: usize,
) -> Option<($src_unit, usize)> {
let unit_size = ::std::mem::size_of::<$src_unit>();
let mut offset = 0usize;
// This loop is only broken out of as a goto forward without
// actually looping
'outer: loop {
if SIMD_STRIDE_SIZE <= len {
// First, process one unaligned
if !$stride_neither_aligned(src, dst) {
break 'outer;
}
offset = SIMD_STRIDE_SIZE;
// We have now seen 16 ASCII bytes. Let's guess that
// there will be enough more to justify more expense
// in the case of non-ASCII.
// Use aligned reads for the sake of old microachitectures.
let until_alignment = ((SIMD_ALIGNMENT
- ((src.add(offset) as usize) & SIMD_ALIGNMENT_MASK))
& SIMD_ALIGNMENT_MASK)
/ unit_size;
// This addition won't overflow, because even in the 32-bit PAE case the
// address space holds enough code that the slice length can't be that
// close to address space size.
// offset now equals SIMD_STRIDE_SIZE, hence times 3 below.
if until_alignment + (SIMD_STRIDE_SIZE * 3) <= len {
if until_alignment != 0 {
if !$stride_neither_aligned(src.add(offset), dst.add(offset)) {
break;
}
offset += until_alignment;
}
let len_minus_stride_times_two = len - (SIMD_STRIDE_SIZE * 2);
let dst_masked = (dst.add(offset) as usize) & SIMD_ALIGNMENT_MASK;
if dst_masked == 0 {
loop {
if let Some(advance) =
$double_stride_both_aligned(src.add(offset), dst.add(offset))
{
offset += advance;
let code_unit = *(src.add(offset));
return Some((code_unit, offset));
}
offset += SIMD_STRIDE_SIZE * 2;
if offset > len_minus_stride_times_two {
break;
}
}
if offset + SIMD_STRIDE_SIZE <= len {
if !$stride_both_aligned(src.add(offset), dst.add(offset)) {
break 'outer;
}
offset += SIMD_STRIDE_SIZE;
}
} else {
loop {
if let Some(advance) =
$double_stride_src_aligned(src.add(offset), dst.add(offset))
{
offset += advance;
let code_unit = *(src.add(offset));
return Some((code_unit, offset));
}
offset += SIMD_STRIDE_SIZE * 2;
if offset > len_minus_stride_times_two {
break;
}
}
if offset + SIMD_STRIDE_SIZE <= len {
if !$stride_src_aligned(src.add(offset), dst.add(offset)) {
break 'outer;
}
offset += SIMD_STRIDE_SIZE;
}
}
} else {
// At most two iterations, so unroll
if offset + SIMD_STRIDE_SIZE <= len {
if !$stride_neither_aligned(src.add(offset), dst.add(offset)) {
break;
}
offset += SIMD_STRIDE_SIZE;
if offset + SIMD_STRIDE_SIZE <= len {
if !$stride_neither_aligned(src.add(offset), dst.add(offset)) {
break;
}
offset += SIMD_STRIDE_SIZE;
}
}
}
}
break 'outer;
}
while offset < len {
let code_unit = *(src.add(offset));
if code_unit > 127 {
return Some((code_unit, offset));
}
*(dst.add(offset)) = code_unit as $dst_unit;
offset += 1;
}
None
}
};
}
#[allow(unused_macros)]
macro_rules! latin1_simd_check_align {
(
$name:ident,
$src_unit:ty,
$dst_unit:ty,
$stride_both_aligned:ident,
$stride_src_aligned:ident,
$stride_dst_aligned:ident,
$stride_neither_aligned:ident
) => {
#[inline(always)]
pub unsafe fn $name(src: *const $src_unit, dst: *mut $dst_unit, len: usize) {
let mut offset = 0usize;
if SIMD_STRIDE_SIZE <= len {
let len_minus_stride = len - SIMD_STRIDE_SIZE;
let dst_masked = (dst as usize) & SIMD_ALIGNMENT_MASK;
if ((src as usize) & SIMD_ALIGNMENT_MASK) == 0 {
if dst_masked == 0 {
loop {
$stride_both_aligned(src.add(offset), dst.add(offset));
offset += SIMD_STRIDE_SIZE;
if offset > len_minus_stride {
break;
}
}
} else {
loop {
$stride_src_aligned(src.add(offset), dst.add(offset));
offset += SIMD_STRIDE_SIZE;
if offset > len_minus_stride {
break;
}
}
}
} else {
if dst_masked == 0 {
loop {
$stride_dst_aligned(src.add(offset), dst.add(offset));
offset += SIMD_STRIDE_SIZE;
if offset > len_minus_stride {
break;
}
}
} else {
loop {
$stride_neither_aligned(src.add(offset), dst.add(offset));
offset += SIMD_STRIDE_SIZE;
if offset > len_minus_stride {
break;
}
}
}
}
}
while offset < len {
let code_unit = *(src.add(offset));
*(dst.add(offset)) = code_unit as $dst_unit;
offset += 1;
}
}
};
}
#[allow(unused_macros)]
macro_rules! latin1_simd_check_align_unrolled {
(
$name:ident,
$src_unit:ty,
$dst_unit:ty,
$stride_both_aligned:ident,
$stride_src_aligned:ident,
$stride_dst_aligned:ident,
$stride_neither_aligned:ident
) => {
#[inline(always)]
pub unsafe fn $name(src: *const $src_unit, dst: *mut $dst_unit, len: usize) {
let unit_size = ::std::mem::size_of::<$src_unit>();
let mut offset = 0usize;
if SIMD_STRIDE_SIZE <= len {
let mut until_alignment = ((SIMD_STRIDE_SIZE
- ((src as usize) & SIMD_ALIGNMENT_MASK))
& SIMD_ALIGNMENT_MASK)
/ unit_size;
while until_alignment != 0 {
*(dst.add(offset)) = *(src.add(offset)) as $dst_unit;
offset += 1;
until_alignment -= 1;
}
let len_minus_stride = len - SIMD_STRIDE_SIZE;
if offset + SIMD_STRIDE_SIZE * 2 <= len {
let len_minus_stride_times_two = len_minus_stride - SIMD_STRIDE_SIZE;
if (dst.add(offset) as usize) & SIMD_ALIGNMENT_MASK == 0 {
loop {
$stride_both_aligned(src.add(offset), dst.add(offset));
offset += SIMD_STRIDE_SIZE;
$stride_both_aligned(src.add(offset), dst.add(offset));
offset += SIMD_STRIDE_SIZE;
if offset > len_minus_stride_times_two {
break;
}
}
} else {
loop {
$stride_src_aligned(src.add(offset), dst.add(offset));
offset += SIMD_STRIDE_SIZE;
$stride_src_aligned(src.add(offset), dst.add(offset));
offset += SIMD_STRIDE_SIZE;
if offset > len_minus_stride_times_two {
break;
}
}
}
}
if offset < len_minus_stride {
$stride_src_aligned(src.add(offset), dst.add(offset));
offset += SIMD_STRIDE_SIZE;
}
}
while offset < len {
let code_unit = *(src.add(offset));
// On x86_64, this loop autovectorizes but in the pack
// case there are instructions whose purpose is to make sure
// each u16 in the vector is truncated before packing. However,
// since we don't care about saturating behavior of SSE2 packing
// when the input isn't Latin1, those instructions are useless.
// Unfortunately, using the `assume` intrinsic to lie to the
// optimizer doesn't make LLVM omit the trunctation that we
// don't need. Possibly this loop could be manually optimized
// to do the sort of thing that LLVM does but without the
// ANDing the read vectors of u16 with a constant that discards
// the high half of each u16. As far as I can tell, the
// optimization assumes that doing a SIMD read past the end of
// the array is OK.
*(dst.add(offset)) = code_unit as $dst_unit;
offset += 1;
}
}
};
}
#[allow(unused_macros)]
macro_rules! ascii_simd_unalign {
($name:ident, $src_unit:ty, $dst_unit:ty, $stride_neither_aligned:ident) => {
#[inline(always)]
pub unsafe fn $name(
src: *const $src_unit,
dst: *mut $dst_unit,
len: usize,
) -> Option<($src_unit, usize)> {
let mut offset = 0usize;
if SIMD_STRIDE_SIZE <= len {
let len_minus_stride = len - SIMD_STRIDE_SIZE;
loop {
if !$stride_neither_aligned(src.add(offset), dst.add(offset)) {
break;
}
offset += SIMD_STRIDE_SIZE;
if offset > len_minus_stride {
break;
}
}
}
while offset < len {
let code_unit = *(src.add(offset));
if code_unit > 127 {
return Some((code_unit, offset));
}
*(dst.add(offset)) = code_unit as $dst_unit;
offset += 1;
}
None
}
};
}
#[allow(unused_macros)]
macro_rules! latin1_simd_unalign {
($name:ident, $src_unit:ty, $dst_unit:ty, $stride_neither_aligned:ident) => {
#[inline(always)]
pub unsafe fn $name(src: *const $src_unit, dst: *mut $dst_unit, len: usize) {
let mut offset = 0usize;
if SIMD_STRIDE_SIZE <= len {
let len_minus_stride = len - SIMD_STRIDE_SIZE;
loop {
$stride_neither_aligned(src.add(offset), dst.add(offset));
offset += SIMD_STRIDE_SIZE;
if offset > len_minus_stride {
break;
}
}
}
while offset < len {
let code_unit = *(src.add(offset));
*(dst.add(offset)) = code_unit as $dst_unit;
offset += 1;
}
}
};
}
#[allow(unused_macros)]
macro_rules! ascii_to_ascii_simd_stride {
($name:ident, $load:ident, $store:ident) => {
#[inline(always)]
pub unsafe fn $name(src: *const u8, dst: *mut u8) -> bool {
let simd = $load(src);
if !simd_is_ascii(simd) {
return false;
}
$store(dst, simd);
true
}
};
}
#[allow(unused_macros)]
macro_rules! ascii_to_ascii_simd_double_stride {
($name:ident, $store:ident) => {
#[inline(always)]
pub unsafe fn $name(src: *const u8, dst: *mut u8) -> Option<usize> {
let first = load16_aligned(src);
let second = load16_aligned(src.add(SIMD_STRIDE_SIZE));
$store(dst, first);
if unlikely(!simd_is_ascii(first | second)) {
let mask_first = mask_ascii(first);
if mask_first != 0 {
return Some(mask_first.trailing_zeros() as usize);
}
$store(dst.add(SIMD_STRIDE_SIZE), second);
let mask_second = mask_ascii(second);
return Some(SIMD_STRIDE_SIZE + mask_second.trailing_zeros() as usize);
}
$store(dst.add(SIMD_STRIDE_SIZE), second);
None
}
};
}
#[allow(unused_macros)]
macro_rules! ascii_to_basic_latin_simd_stride {
($name:ident, $load:ident, $store:ident) => {
#[inline(always)]
pub unsafe fn $name(src: *const u8, dst: *mut u16) -> bool {
let simd = $load(src);
if !simd_is_ascii(simd) {
return false;
}
let (first, second) = simd_unpack(simd);
$store(dst, first);
$store(dst.add(8), second);
true
}
};
}
#[allow(unused_macros)]
macro_rules! ascii_to_basic_latin_simd_double_stride {
($name:ident, $store:ident) => {
#[inline(always)]
pub unsafe fn $name(src: *const u8, dst: *mut u16) -> Option<usize> {
let first = load16_aligned(src);
let second = load16_aligned(src.add(SIMD_STRIDE_SIZE));
let (a, b) = simd_unpack(first);
$store(dst, a);
$store(dst.add(SIMD_STRIDE_SIZE / 2), b);
if unlikely(!simd_is_ascii(first | second)) {
let mask_first = mask_ascii(first);
if mask_first != 0 {
return Some(mask_first.trailing_zeros() as usize);
}
let (c, d) = simd_unpack(second);
$store(dst.add(SIMD_STRIDE_SIZE), c);
$store(dst.add(SIMD_STRIDE_SIZE + (SIMD_STRIDE_SIZE / 2)), d);
let mask_second = mask_ascii(second);
return Some(SIMD_STRIDE_SIZE + mask_second.trailing_zeros() as usize);
}
let (c, d) = simd_unpack(second);
$store(dst.add(SIMD_STRIDE_SIZE), c);
$store(dst.add(SIMD_STRIDE_SIZE + (SIMD_STRIDE_SIZE / 2)), d);
None
}
};
}
#[allow(unused_macros)]
macro_rules! unpack_simd_stride {
($name:ident, $load:ident, $store:ident) => {
#[inline(always)]
pub unsafe fn $name(src: *const u8, dst: *mut u16) {
let simd = $load(src);
let (first, second) = simd_unpack(simd);
$store(dst, first);
$store(dst.add(8), second);
}
};
}
#[allow(unused_macros)]
macro_rules! basic_latin_to_ascii_simd_stride {
($name:ident, $load:ident, $store:ident) => {
#[inline(always)]
pub unsafe fn $name(src: *const u16, dst: *mut u8) -> bool {
let first = $load(src);
let second = $load(src.add(8));
if simd_is_basic_latin(first | second) {
$store(dst, simd_pack(first, second));
true
} else {
false
}
}
};
}
#[allow(unused_macros)]
macro_rules! pack_simd_stride {
($name:ident, $load:ident, $store:ident) => {
#[inline(always)]
pub unsafe fn $name(src: *const u16, dst: *mut u8) {
let first = $load(src);
let second = $load(src.add(8));
$store(dst, simd_pack(first, second));
}
};
}
cfg_if! {
if #[cfg(all(feature = "simd-accel", target_endian = "little", target_arch = "aarch64"))] {
// SIMD with the same instructions for aligned and unaligned loads and stores
pub const SIMD_STRIDE_SIZE: usize = 16;
pub const MAX_STRIDE_SIZE: usize = 16;
// pub const ALIGNMENT: usize = 8;
pub const ALU_STRIDE_SIZE: usize = 16;
pub const ALU_ALIGNMENT: usize = 8;
pub const ALU_ALIGNMENT_MASK: usize = 7;
ascii_to_ascii_simd_stride!(ascii_to_ascii_stride_neither_aligned, load16_unaligned, store16_unaligned);
ascii_to_basic_latin_simd_stride!(ascii_to_basic_latin_stride_neither_aligned, load16_unaligned, store8_unaligned);
unpack_simd_stride!(unpack_stride_neither_aligned, load16_unaligned, store8_unaligned);
basic_latin_to_ascii_simd_stride!(basic_latin_to_ascii_stride_neither_aligned, load8_unaligned, store16_unaligned);
pack_simd_stride!(pack_stride_neither_aligned, load8_unaligned, store16_unaligned);
ascii_simd_unalign!(ascii_to_ascii, u8, u8, ascii_to_ascii_stride_neither_aligned);
ascii_simd_unalign!(ascii_to_basic_latin, u8, u16, ascii_to_basic_latin_stride_neither_aligned);
ascii_simd_unalign!(basic_latin_to_ascii, u16, u8, basic_latin_to_ascii_stride_neither_aligned);
latin1_simd_unalign!(unpack_latin1, u8, u16, unpack_stride_neither_aligned);
latin1_simd_unalign!(pack_latin1, u16, u8, pack_stride_neither_aligned);
} else if #[cfg(all(feature = "simd-accel", target_endian = "little", target_feature = "neon"))] {
// SIMD with different instructions for aligned and unaligned loads and stores.
//
// Newer microarchitectures are not supposed to have a performance difference between
// aligned and unaligned SSE2 loads and stores when the address is actually aligned,
// but the benchmark results I see don't agree.
pub const SIMD_STRIDE_SIZE: usize = 16;
pub const MAX_STRIDE_SIZE: usize = 16;
pub const SIMD_ALIGNMENT_MASK: usize = 15;
ascii_to_ascii_simd_stride!(ascii_to_ascii_stride_both_aligned, load16_aligned, store16_aligned);
ascii_to_ascii_simd_stride!(ascii_to_ascii_stride_src_aligned, load16_aligned, store16_unaligned);
ascii_to_ascii_simd_stride!(ascii_to_ascii_stride_dst_aligned, load16_unaligned, store16_aligned);
ascii_to_ascii_simd_stride!(ascii_to_ascii_stride_neither_aligned, load16_unaligned, store16_unaligned);
ascii_to_basic_latin_simd_stride!(ascii_to_basic_latin_stride_both_aligned, load16_aligned, store8_aligned);
ascii_to_basic_latin_simd_stride!(ascii_to_basic_latin_stride_src_aligned, load16_aligned, store8_unaligned);
ascii_to_basic_latin_simd_stride!(ascii_to_basic_latin_stride_dst_aligned, load16_unaligned, store8_aligned);
ascii_to_basic_latin_simd_stride!(ascii_to_basic_latin_stride_neither_aligned, load16_unaligned, store8_unaligned);
unpack_simd_stride!(unpack_stride_both_aligned, load16_aligned, store8_aligned);
unpack_simd_stride!(unpack_stride_src_aligned, load16_aligned, store8_unaligned);
unpack_simd_stride!(unpack_stride_dst_aligned, load16_unaligned, store8_aligned);
unpack_simd_stride!(unpack_stride_neither_aligned, load16_unaligned, store8_unaligned);
basic_latin_to_ascii_simd_stride!(basic_latin_to_ascii_stride_both_aligned, load8_aligned, store16_aligned);
basic_latin_to_ascii_simd_stride!(basic_latin_to_ascii_stride_src_aligned, load8_aligned, store16_unaligned);
basic_latin_to_ascii_simd_stride!(basic_latin_to_ascii_stride_dst_aligned, load8_unaligned, store16_aligned);
basic_latin_to_ascii_simd_stride!(basic_latin_to_ascii_stride_neither_aligned, load8_unaligned, store16_unaligned);
pack_simd_stride!(pack_stride_both_aligned, load8_aligned, store16_aligned);
pack_simd_stride!(pack_stride_src_aligned, load8_aligned, store16_unaligned);
pack_simd_stride!(pack_stride_dst_aligned, load8_unaligned, store16_aligned);
pack_simd_stride!(pack_stride_neither_aligned, load8_unaligned, store16_unaligned);
ascii_simd_check_align!(ascii_to_ascii, u8, u8, ascii_to_ascii_stride_both_aligned, ascii_to_ascii_stride_src_aligned, ascii_to_ascii_stride_dst_aligned, ascii_to_ascii_stride_neither_aligned);
ascii_simd_check_align!(ascii_to_basic_latin, u8, u16, ascii_to_basic_latin_stride_both_aligned, ascii_to_basic_latin_stride_src_aligned, ascii_to_basic_latin_stride_dst_aligned, ascii_to_basic_latin_stride_neither_aligned);
ascii_simd_check_align!(basic_latin_to_ascii, u16, u8, basic_latin_to_ascii_stride_both_aligned, basic_latin_to_ascii_stride_src_aligned, basic_latin_to_ascii_stride_dst_aligned, basic_latin_to_ascii_stride_neither_aligned);
latin1_simd_check_align!(unpack_latin1, u8, u16, unpack_stride_both_aligned, unpack_stride_src_aligned, unpack_stride_dst_aligned, unpack_stride_neither_aligned);
latin1_simd_check_align!(pack_latin1, u16, u8, pack_stride_both_aligned, pack_stride_src_aligned, pack_stride_dst_aligned, pack_stride_neither_aligned);
} else if #[cfg(all(feature = "simd-accel", target_feature = "sse2"))] {
// SIMD with different instructions for aligned and unaligned loads and stores.
//
// Newer microarchitectures are not supposed to have a performance difference between
// aligned and unaligned SSE2 loads and stores when the address is actually aligned,
// but the benchmark results I see don't agree.
pub const SIMD_STRIDE_SIZE: usize = 16;
pub const SIMD_ALIGNMENT: usize = 16;
pub const MAX_STRIDE_SIZE: usize = 16;
pub const SIMD_ALIGNMENT_MASK: usize = 15;
ascii_to_ascii_simd_double_stride!(ascii_to_ascii_simd_double_stride_both_aligned, store16_aligned);
ascii_to_ascii_simd_double_stride!(ascii_to_ascii_simd_double_stride_src_aligned, store16_unaligned);
ascii_to_basic_latin_simd_double_stride!(ascii_to_basic_latin_simd_double_stride_both_aligned, store8_aligned);
ascii_to_basic_latin_simd_double_stride!(ascii_to_basic_latin_simd_double_stride_src_aligned, store8_unaligned);
ascii_to_ascii_simd_stride!(ascii_to_ascii_stride_both_aligned, load16_aligned, store16_aligned);
ascii_to_ascii_simd_stride!(ascii_to_ascii_stride_src_aligned, load16_aligned, store16_unaligned);
ascii_to_ascii_simd_stride!(ascii_to_ascii_stride_neither_aligned, load16_unaligned, store16_unaligned);
ascii_to_basic_latin_simd_stride!(ascii_to_basic_latin_stride_both_aligned, load16_aligned, store8_aligned);
ascii_to_basic_latin_simd_stride!(ascii_to_basic_latin_stride_src_aligned, load16_aligned, store8_unaligned);
ascii_to_basic_latin_simd_stride!(ascii_to_basic_latin_stride_neither_aligned, load16_unaligned, store8_unaligned);
unpack_simd_stride!(unpack_stride_both_aligned, load16_aligned, store8_aligned);
unpack_simd_stride!(unpack_stride_src_aligned, load16_aligned, store8_unaligned);
basic_latin_to_ascii_simd_stride!(basic_latin_to_ascii_stride_both_aligned, load8_aligned, store16_aligned);
basic_latin_to_ascii_simd_stride!(basic_latin_to_ascii_stride_src_aligned, load8_aligned, store16_unaligned);
basic_latin_to_ascii_simd_stride!(basic_latin_to_ascii_stride_dst_aligned, load8_unaligned, store16_aligned);
basic_latin_to_ascii_simd_stride!(basic_latin_to_ascii_stride_neither_aligned, load8_unaligned, store16_unaligned);
pack_simd_stride!(pack_stride_both_aligned, load8_aligned, store16_aligned);
pack_simd_stride!(pack_stride_src_aligned, load8_aligned, store16_unaligned);
ascii_simd_check_align_unrolled!(ascii_to_ascii, u8, u8, ascii_to_ascii_stride_both_aligned, ascii_to_ascii_stride_src_aligned, ascii_to_ascii_stride_neither_aligned, ascii_to_ascii_simd_double_stride_both_aligned, ascii_to_ascii_simd_double_stride_src_aligned);
ascii_simd_check_align_unrolled!(ascii_to_basic_latin, u8, u16, ascii_to_basic_latin_stride_both_aligned, ascii_to_basic_latin_stride_src_aligned, ascii_to_basic_latin_stride_neither_aligned, ascii_to_basic_latin_simd_double_stride_both_aligned, ascii_to_basic_latin_simd_double_stride_src_aligned);
ascii_simd_check_align!(basic_latin_to_ascii, u16, u8, basic_latin_to_ascii_stride_both_aligned, basic_latin_to_ascii_stride_src_aligned, basic_latin_to_ascii_stride_dst_aligned, basic_latin_to_ascii_stride_neither_aligned);
latin1_simd_check_align_unrolled!(unpack_latin1, u8, u16, unpack_stride_both_aligned, unpack_stride_src_aligned, unpack_stride_dst_aligned, unpack_stride_neither_aligned);
latin1_simd_check_align_unrolled!(pack_latin1, u16, u8, pack_stride_both_aligned, pack_stride_src_aligned, pack_stride_dst_aligned, pack_stride_neither_aligned);
} else if #[cfg(all(target_endian = "little", target_pointer_width = "64"))] {
// Aligned ALU word, little-endian, 64-bit
pub const ALU_STRIDE_SIZE: usize = 16;
pub const MAX_STRIDE_SIZE: usize = 16;
pub const ALU_ALIGNMENT: usize = 8;
pub const ALU_ALIGNMENT_MASK: usize = 7;
#[inline(always)]
unsafe fn unpack_alu(word: usize, second_word: usize, dst: *mut usize) {
let first = ((0x0000_0000_FF00_0000usize & word) << 24) |
((0x0000_0000_00FF_0000usize & word) << 16) |
((0x0000_0000_0000_FF00usize & word) << 8) |
(0x0000_0000_0000_00FFusize & word);
let second = ((0xFF00_0000_0000_0000usize & word) >> 8) |
((0x00FF_0000_0000_0000usize & word) >> 16) |
((0x0000_FF00_0000_0000usize & word) >> 24) |
((0x0000_00FF_0000_0000usize & word) >> 32);
let third = ((0x0000_0000_FF00_0000usize & second_word) << 24) |
((0x0000_0000_00FF_0000usize & second_word) << 16) |
((0x0000_0000_0000_FF00usize & second_word) << 8) |
(0x0000_0000_0000_00FFusize & second_word);
let fourth = ((0xFF00_0000_0000_0000usize & second_word) >> 8) |
((0x00FF_0000_0000_0000usize & second_word) >> 16) |
((0x0000_FF00_0000_0000usize & second_word) >> 24) |
((0x0000_00FF_0000_0000usize & second_word) >> 32);
*dst = first;
*(dst.add(1)) = second;
*(dst.add(2)) = third;
*(dst.add(3)) = fourth;
}
#[inline(always)]
unsafe fn pack_alu(first: usize, second: usize, third: usize, fourth: usize, dst: *mut usize) {
let word = ((0x00FF_0000_0000_0000usize & second) << 8) |
((0x0000_00FF_0000_0000usize & second) << 16) |
((0x0000_0000_00FF_0000usize & second) << 24) |
((0x0000_0000_0000_00FFusize & second) << 32) |
((0x00FF_0000_0000_0000usize & first) >> 24) |
((0x0000_00FF_0000_0000usize & first) >> 16) |
((0x0000_0000_00FF_0000usize & first) >> 8) |
(0x0000_0000_0000_00FFusize & first);
let second_word = ((0x00FF_0000_0000_0000usize & fourth) << 8) |
((0x0000_00FF_0000_0000usize & fourth) << 16) |
((0x0000_0000_00FF_0000usize & fourth) << 24) |
((0x0000_0000_0000_00FFusize & fourth) << 32) |
((0x00FF_0000_0000_0000usize & third) >> 24) |
((0x0000_00FF_0000_0000usize & third) >> 16) |
((0x0000_0000_00FF_0000usize & third) >> 8) |
(0x0000_0000_0000_00FFusize & third);
*dst = word;
*(dst.add(1)) = second_word;
}
} else if #[cfg(all(target_endian = "little", target_pointer_width = "32"))] {
// Aligned ALU word, little-endian, 32-bit
pub const ALU_STRIDE_SIZE: usize = 8;
pub const MAX_STRIDE_SIZE: usize = 8;
pub const ALU_ALIGNMENT: usize = 4;
pub const ALU_ALIGNMENT_MASK: usize = 3;
#[inline(always)]
unsafe fn unpack_alu(word: usize, second_word: usize, dst: *mut usize) {
let first = ((0x0000_FF00usize & word) << 8) |
(0x0000_00FFusize & word);
let second = ((0xFF00_0000usize & word) >> 8) |
((0x00FF_0000usize & word) >> 16);
let third = ((0x0000_FF00usize & second_word) << 8) |
(0x0000_00FFusize & second_word);
let fourth = ((0xFF00_0000usize & second_word) >> 8) |
((0x00FF_0000usize & second_word) >> 16);
*dst = first;
*(dst.add(1)) = second;
*(dst.add(2)) = third;
*(dst.add(3)) = fourth;
}
#[inline(always)]
unsafe fn pack_alu(first: usize, second: usize, third: usize, fourth: usize, dst: *mut usize) {
let word = ((0x00FF_0000usize & second) << 8) |
((0x0000_00FFusize & second) << 16) |
((0x00FF_0000usize & first) >> 8) |
(0x0000_00FFusize & first);
let second_word = ((0x00FF_0000usize & fourth) << 8) |
((0x0000_00FFusize & fourth) << 16) |
((0x00FF_0000usize & third) >> 8) |
(0x0000_00FFusize & third);
*dst = word;
*(dst.add(1)) = second_word;
}
} else if #[cfg(all(target_endian = "big", target_pointer_width = "64"))] {
// Aligned ALU word, big-endian, 64-bit
pub const ALU_STRIDE_SIZE: usize = 16;
pub const MAX_STRIDE_SIZE: usize = 16;
pub const ALU_ALIGNMENT: usize = 8;
pub const ALU_ALIGNMENT_MASK: usize = 7;
#[inline(always)]
unsafe fn unpack_alu(word: usize, second_word: usize, dst: *mut usize) {
let first = ((0xFF00_0000_0000_0000usize & word) >> 8) |
((0x00FF_0000_0000_0000usize & word) >> 16) |
((0x0000_FF00_0000_0000usize & word) >> 24) |
((0x0000_00FF_0000_0000usize & word) >> 32);
let second = ((0x0000_0000_FF00_0000usize & word) << 24) |
((0x0000_0000_00FF_0000usize & word) << 16) |
((0x0000_0000_0000_FF00usize & word) << 8) |
(0x0000_0000_0000_00FFusize & word);
let third = ((0xFF00_0000_0000_0000usize & second_word) >> 8) |
((0x00FF_0000_0000_0000usize & second_word) >> 16) |
((0x0000_FF00_0000_0000usize & second_word) >> 24) |
((0x0000_00FF_0000_0000usize & second_word) >> 32);
let fourth = ((0x0000_0000_FF00_0000usize & second_word) << 24) |
((0x0000_0000_00FF_0000usize & second_word) << 16) |
((0x0000_0000_0000_FF00usize & second_word) << 8) |
(0x0000_0000_0000_00FFusize & second_word);
*dst = first;
*(dst.add(1)) = second;
*(dst.add(2)) = third;
*(dst.add(3)) = fourth;
}
#[inline(always)]
unsafe fn pack_alu(first: usize, second: usize, third: usize, fourth: usize, dst: *mut usize) {
let word = ((0x00FF0000_00000000usize & first) << 8) |
((0x000000FF_00000000usize & first) << 16) |
((0x00000000_00FF0000usize & first) << 24) |
((0x00000000_000000FFusize & first) << 32) |
((0x00FF0000_00000000usize & second) >> 24) |
((0x000000FF_00000000usize & second) >> 16) |
((0x00000000_00FF0000usize & second) >> 8) |
(0x00000000_000000FFusize & second);
let second_word = ((0x00FF0000_00000000usize & third) << 8) |
((0x000000FF_00000000usize & third) << 16) |
((0x00000000_00FF0000usize & third) << 24) |
((0x00000000_000000FFusize & third) << 32) |
((0x00FF0000_00000000usize & fourth) >> 24) |
((0x000000FF_00000000usize & fourth) >> 16) |
((0x00000000_00FF0000usize & fourth) >> 8) |
(0x00000000_000000FFusize & fourth);
*dst = word;
*(dst.add(1)) = second_word;
}
} else if #[cfg(all(target_endian = "big", target_pointer_width = "32"))] {
// Aligned ALU word, big-endian, 32-bit
pub const ALU_STRIDE_SIZE: usize = 8;
pub const MAX_STRIDE_SIZE: usize = 8;
pub const ALU_ALIGNMENT: usize = 4;
pub const ALU_ALIGNMENT_MASK: usize = 3;
#[inline(always)]
unsafe fn unpack_alu(word: usize, second_word: usize, dst: *mut usize) {
let first = ((0xFF00_0000usize & word) >> 8) |
((0x00FF_0000usize & word) >> 16);
let second = ((0x0000_FF00usize & word) << 8) |
(0x0000_00FFusize & word);
let third = ((0xFF00_0000usize & second_word) >> 8) |
((0x00FF_0000usize & second_word) >> 16);
let fourth = ((0x0000_FF00usize & second_word) << 8) |
(0x0000_00FFusize & second_word);
*dst = first;
*(dst.add(1)) = second;
*(dst.add(2)) = third;
*(dst.add(3)) = fourth;
}
#[inline(always)]
unsafe fn pack_alu(first: usize, second: usize, third: usize, fourth: usize, dst: *mut usize) {
let word = ((0x00FF_0000usize & first) << 8) |
((0x0000_00FFusize & first) << 16) |
((0x00FF_0000usize & second) >> 8) |
(0x0000_00FFusize & second);
let second_word = ((0x00FF_0000usize & third) << 8) |
((0x0000_00FFusize & third) << 16) |
((0x00FF_0000usize & fourth) >> 8) |
(0x0000_00FFusize & fourth);
*dst = word;
*(dst.add(1)) = second_word;
}
} else {
ascii_naive!(ascii_to_ascii, u8, u8);
ascii_naive!(ascii_to_basic_latin, u8, u16);
ascii_naive!(basic_latin_to_ascii, u16, u8);
}
}
cfg_if! {
if #[cfg(target_endian = "little")] {
#[allow(dead_code)]
#[inline(always)]
fn count_zeros(word: usize) -> u32 {
word.trailing_zeros()
}
} else {
#[allow(dead_code)]
#[inline(always)]
fn count_zeros(word: usize) -> u32 {
word.leading_zeros()
}
}
}
cfg_if! {
if #[cfg(all(feature = "simd-accel", target_endian = "little", target_arch = "disabled"))] {
#[inline(always)]
pub fn validate_ascii(slice: &[u8]) -> Option<(u8, usize)> {
let src = slice.as_ptr();
let len = slice.len();
let mut offset = 0usize;
if SIMD_STRIDE_SIZE <= len {
let len_minus_stride = len - SIMD_STRIDE_SIZE;
loop {
let simd = unsafe { load16_unaligned(src.add(offset)) };
if !simd_is_ascii(simd) {
break;
}
offset += SIMD_STRIDE_SIZE;
if offset > len_minus_stride {
break;
}
}
}
while offset < len {
let code_unit = slice[offset];
if code_unit > 127 {
return Some((code_unit, offset));
}
offset += 1;
}
None
}
} else if #[cfg(all(feature = "simd-accel", target_feature = "sse2"))] {
#[inline(always)]
pub fn validate_ascii(slice: &[u8]) -> Option<(u8, usize)> {
let src = slice.as_ptr();
let len = slice.len();
let mut offset = 0usize;
if SIMD_STRIDE_SIZE <= len {
// First, process one unaligned vector
let simd = unsafe { load16_unaligned(src) };
let mask = mask_ascii(simd);
if mask != 0 {
offset = mask.trailing_zeros() as usize;
let non_ascii = unsafe { *src.add(offset) };
return Some((non_ascii, offset));
}
offset = SIMD_STRIDE_SIZE;
// We have now seen 16 ASCII bytes. Let's guess that
// there will be enough more to justify more expense
// in the case of non-ASCII.
// Use aligned reads for the sake of old microachitectures.
let until_alignment = unsafe { (SIMD_ALIGNMENT - ((src.add(offset) as usize) & SIMD_ALIGNMENT_MASK)) & SIMD_ALIGNMENT_MASK };
// This addition won't overflow, because even in the 32-bit PAE case the
// address space holds enough code that the slice length can't be that
// close to address space size.
// offset now equals SIMD_STRIDE_SIZE, hence times 3 below.
if until_alignment + (SIMD_STRIDE_SIZE * 3) <= len {
if until_alignment != 0 {
let simd = unsafe { load16_unaligned(src.add(offset)) };
let mask = mask_ascii(simd);
if mask != 0 {
offset += mask.trailing_zeros() as usize;
let non_ascii = unsafe { *src.add(offset) };
return Some((non_ascii, offset));
}
offset += until_alignment;
}
let len_minus_stride_times_two = len - (SIMD_STRIDE_SIZE * 2);
loop {
let first = unsafe { load16_aligned(src.add(offset)) };
let second = unsafe { load16_aligned(src.add(offset + SIMD_STRIDE_SIZE)) };
if !simd_is_ascii(first | second) {
let mask_first = mask_ascii(first);
if mask_first != 0 {
offset += mask_first.trailing_zeros() as usize;
} else {
let mask_second = mask_ascii(second);
offset += SIMD_STRIDE_SIZE + mask_second.trailing_zeros() as usize;
}
let non_ascii = unsafe { *src.add(offset) };
return Some((non_ascii, offset));
}
offset += SIMD_STRIDE_SIZE * 2;
if offset > len_minus_stride_times_two {
break;
}
}
if offset + SIMD_STRIDE_SIZE <= len {
let simd = unsafe { load16_aligned(src.add(offset)) };
let mask = mask_ascii(simd);
if mask != 0 {
offset += mask.trailing_zeros() as usize;
let non_ascii = unsafe { *src.add(offset) };
return Some((non_ascii, offset));
}
offset += SIMD_STRIDE_SIZE;
}
} else {
// At most two iterations, so unroll
if offset + SIMD_STRIDE_SIZE <= len {
let simd = unsafe { load16_unaligned(src.add(offset)) };
let mask = mask_ascii(simd);
if mask != 0 {
offset += mask.trailing_zeros() as usize;
let non_ascii = unsafe { *src.add(offset) };
return Some((non_ascii, offset));
}
offset += SIMD_STRIDE_SIZE;
if offset + SIMD_STRIDE_SIZE <= len {
let simd = unsafe { load16_unaligned(src.add(offset)) };
let mask = mask_ascii(simd);
if mask != 0 {
offset += mask.trailing_zeros() as usize;
let non_ascii = unsafe { *src.add(offset) };
return Some((non_ascii, offset));
}
offset += SIMD_STRIDE_SIZE;
}
}
}
}
while offset < len {
let code_unit = unsafe { *(src.add(offset)) };
if code_unit > 127 {
return Some((code_unit, offset));
}
offset += 1;
}
None
}
} else {
#[inline(always)]
fn find_non_ascii(word: usize, second_word: usize) -> Option<usize> {
let word_masked = word & ASCII_MASK;
let second_masked = second_word & ASCII_MASK;
if (word_masked | second_masked) == 0 {
return None;
}
if word_masked != 0 {
let zeros = count_zeros(word_masked);
// `zeros` now contains 7 (for the seven bits of non-ASCII)
// plus 8 times the number of ASCII in text order before the
// non-ASCII byte in the little-endian case or 8 times the number of ASCII in
// text order before the non-ASCII byte in the big-endian case.
let num_ascii = (zeros >> 3) as usize;
return Some(num_ascii);
}
let zeros = count_zeros(second_masked);
// `zeros` now contains 7 (for the seven bits of non-ASCII)
// plus 8 times the number of ASCII in text order before the
// non-ASCII byte in the little-endian case or 8 times the number of ASCII in
// text order before the non-ASCII byte in the big-endian case.
let num_ascii = (zeros >> 3) as usize;
Some(ALU_ALIGNMENT + num_ascii)
}
#[inline(always)]
unsafe fn validate_ascii_stride(src: *const usize) -> Option<usize> {
let word = *src;
let second_word = *(src.add(1));
find_non_ascii(word, second_word)
}
#[cfg_attr(feature = "cargo-clippy", allow(cast_ptr_alignment))]
#[inline(always)]
pub fn validate_ascii(slice: &[u8]) -> Option<(u8, usize)> {
let src = slice.as_ptr();
let len = slice.len();
let mut offset = 0usize;
let mut until_alignment = (ALU_ALIGNMENT - ((src as usize) & ALU_ALIGNMENT_MASK)) & ALU_ALIGNMENT_MASK;
if until_alignment + ALU_STRIDE_SIZE <= len {
while until_alignment != 0 {
let code_unit = slice[offset];
if code_unit > 127 {
return Some((code_unit, offset));
}
offset += 1;
until_alignment -= 1;
}
let len_minus_stride = len - ALU_STRIDE_SIZE;
loop {
let ptr = unsafe { src.add(offset) as *const usize };
if let Some(num_ascii) = unsafe { validate_ascii_stride(ptr) } {
offset += num_ascii;
return Some((unsafe { *(src.add(offset)) }, offset));
}
offset += ALU_STRIDE_SIZE;
if offset > len_minus_stride {
break;
}
}
}
while offset < len {
let code_unit = slice[offset];
if code_unit > 127 {
return Some((code_unit, offset));
}
offset += 1;
}
None
}
}
}
cfg_if! {
if #[cfg(all(feature = "simd-accel", any(target_feature = "sse2", all(target_endian = "little", target_arch = "aarch64"))))] {
} else if #[cfg(all(feature = "simd-accel", target_endian = "little", target_feature = "neon"))] {
// Even with NEON enabled, we use the ALU path for ASCII validation, because testing
// on Exynos 5 indicated that using NEON isn't worthwhile where there are only
// vector reads without vector writes.
pub const ALU_STRIDE_SIZE: usize = 8;
pub const ALU_ALIGNMENT: usize = 4;
pub const ALU_ALIGNMENT_MASK: usize = 3;
} else {
#[inline(always)]
unsafe fn unpack_latin1_stride_alu(src: *const usize, dst: *mut usize) {
let word = *src;
let second_word = *(src.add(1));
unpack_alu(word, second_word, dst);
}
#[inline(always)]
unsafe fn pack_latin1_stride_alu(src: *const usize, dst: *mut usize) {
let first = *src;
let second = *(src.add(1));
let third = *(src.add(2));
let fourth = *(src.add(3));
pack_alu(first, second, third, fourth, dst);
}
#[inline(always)]
unsafe fn ascii_to_basic_latin_stride_alu(src: *const usize, dst: *mut usize) -> bool {
let word = *src;
let second_word = *(src.add(1));
// Check if the words contains non-ASCII
if (word & ASCII_MASK) | (second_word & ASCII_MASK) != 0 {
return false;
}
unpack_alu(word, second_word, dst);
true
}
#[inline(always)]
unsafe fn basic_latin_to_ascii_stride_alu(src: *const usize, dst: *mut usize) -> bool {
let first = *src;
let second = *(src.add(1));
let third = *(src.add(2));
let fourth = *(src.add(3));
if (first & BASIC_LATIN_MASK) | (second & BASIC_LATIN_MASK) | (third & BASIC_LATIN_MASK) | (fourth & BASIC_LATIN_MASK) != 0 {
return false;
}
pack_alu(first, second, third, fourth, dst);
true
}
#[inline(always)]
unsafe fn ascii_to_ascii_stride(src: *const usize, dst: *mut usize) -> Option<usize> {
let word = *src;
let second_word = *(src.add(1));
*dst = word;
*(dst.add(1)) = second_word;
find_non_ascii(word, second_word)
}
basic_latin_alu!(ascii_to_basic_latin, u8, u16, ascii_to_basic_latin_stride_alu);
basic_latin_alu!(basic_latin_to_ascii, u16, u8, basic_latin_to_ascii_stride_alu);
latin1_alu!(unpack_latin1, u8, u16, unpack_latin1_stride_alu);
latin1_alu!(pack_latin1, u16, u8, pack_latin1_stride_alu);
ascii_alu!(ascii_to_ascii, u8, u8, ascii_to_ascii_stride);
}
}
pub fn ascii_valid_up_to(bytes: &[u8]) -> usize {
match validate_ascii(bytes) {
None => bytes.len(),
Some((_, num_valid)) => num_valid,
}
}
pub fn iso_2022_jp_ascii_valid_up_to(bytes: &[u8]) -> usize {
for (i, b_ref) in bytes.iter().enumerate() {
let b = *b_ref;
if b >= 0x80 || b == 0x1B || b == 0x0E || b == 0x0F {
return i;
}
}
bytes.len()
}
// Any copyright to the test code below this comment is dedicated to the
// Public Domain. http://creativecommons.org/publicdomain/zero/1.0/
#[cfg(test)]
mod tests {
use super::*;
macro_rules! test_ascii {
($test_name:ident, $fn_tested:ident, $src_unit:ty, $dst_unit:ty) => {
#[test]
fn $test_name() {
let mut src: Vec<$src_unit> = Vec::with_capacity(32);
let mut dst: Vec<$dst_unit> = Vec::with_capacity(32);
for i in 0..32 {
src.clear();
dst.clear();
dst.resize(32, 0);
for j in 0..32 {
let c = if i == j { 0xAA } else { j + 0x40 };
src.push(c as $src_unit);
}
match unsafe { $fn_tested(src.as_ptr(), dst.as_mut_ptr(), 32) } {
None => unreachable!("Should always find non-ASCII"),
Some((non_ascii, num_ascii)) => {
assert_eq!(non_ascii, 0xAA);
assert_eq!(num_ascii, i);
for j in 0..i {
assert_eq!(dst[j], (j + 0x40) as $dst_unit);
}
}
}
}
}
};
}
test_ascii!(test_ascii_to_ascii, ascii_to_ascii, u8, u8);
test_ascii!(test_ascii_to_basic_latin, ascii_to_basic_latin, u8, u16);
test_ascii!(test_basic_latin_to_ascii, basic_latin_to_ascii, u16, u8);
}
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