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Quellcode-Bibliothek ascii.rs Sprache: unbekannt |
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Spracherkennung für: .rs vermutete Sprache: Unknown {[0] [0] [0]} [Methode: Schwerpunktbildung, einfache Gewichte, sechs Dimensionen] // Copyright 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 crate::simd_funcs::*; cfg_if! { if #[cfg(feature = "simd-accel")] { #[allow(unused_imports)] use ::core::intrinsics::unlikely; #[allow(unused_imports)] use ::core::intrinsics::likely; } else { #[allow(dead_code)] #[inline(always)] fn unlikely(b: bool) -> bool { b } #[allow(dead_code)] #[inline(always)] fn likely(b: bool) -> bool { b } } } // Safety invariants for masks: data & mask = 0 for valid ASCII or basic latin utf-16 // `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) => { /// Safety: src and dst must have len_unit elements and be aligned /// Safety-usable invariant: will return Some() when it fails /// to convert. The first value will be a u8 that is > 127. #[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 { // Safety: len invariant used here let code_unit = *(src.add(i)); // Safety: Upholds safety-usable invariant here if code_unit > 127 { return Some((code_unit, i)); } // Safety: len invariant used here *(dst.add(i)) = code_unit as $dst_unit; } return None; } }; } #[allow(unused_macros)] macro_rules! ascii_alu { ($name:ident, // safety invariant: src/dst MUST be u8 $src_unit:ty, $dst_unit:ty, // Safety invariant: stride_fn must consume and produce two usizes, and return the index of the $stride_fn:ident) => { /// Safety: src and dst must have len elements, src is valid for read, dst is valid for /// write /// Safety-usable invariant: will return Some() when it fails /// to convert. The first value will be a u8 that is > 127. #[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 { // Safety: until_alignment becomes the number of bytes we need to munch until we are aligned to u let mut until_alignment = { // Check if the other unit aligns if we move the narrower unit // to alignment. // if ::core::mem::size_of::<$src_unit>() == ::core::mem::size_of::<$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 { // Safety: bails early and ends up in the naïve branch where usize-alignment doesn't matter break; } (ALU_ALIGNMENT - src_alignment) & ALU_ALIGNMENT_MASK // } else if ::core::mem::size_of::<$src_unit>() < ::core::mem::size_of::<$dst_unit>() { // ascii_to_basic_latin // let src_until_alignment = (ALIGNMENT - ((src as usize) & ALIGNMENT_MASK)) & ALIGN // 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)) & ALIGN // 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. // // Safety: This is the naïve code once again, for `until_alignment` bytes while until_alignment != 0 { let code_unit = *(src.add(offset)); if code_unit > 127 { // Safety: Upholds safety-usable invariant here return Some((code_unit, offset)); } *(dst.add(offset)) = code_unit as $dst_unit; // Safety: offset is the number of bytes copied so far offset += 1; until_alignment -= 1; } let len_minus_stride = len - ALU_STRIDE_SIZE; loop { // Safety: num_ascii is known to be a byte index of a non-ascii byte due to stride_fn's invariant if let Some(num_ascii) = $stride_fn( // Safety: These are known to be valid and aligned since we have at // least ALU_STRIDE_SIZE data in these buffers, and offset is the // number of elements copied so far, which according to the // until_alignment calculation above will cause both src and dst to be // aligned to usize after this add src.add(offset) as *const usize, dst.add(offset) as *mut usize, ) { offset += num_ascii; // Safety: Upholds safety-usable invariant here by indexing into non-ascii byte return Some((*(src.add(offset)), offset)); } // Safety: offset continues to be the number of bytes copied so far, and // maintains usize alignment for the next loop iteration offset += ALU_STRIDE_SIZE; // Safety: This is `offset > len - stride. This loop will continue as long as // `offset <= len - stride`, which means there are `stride` bytes to still be read. if offset > len_minus_stride { break; } } } break; } // Safety: This is the naïve code, same as ascii_naive, and has no requirements // other than src/dst being valid for the the right lens while offset < len { // Safety: len invariant used here let code_unit = *(src.add(offset)); if code_unit > 127 { // Safety: Upholds safety-usable invariant here return Some((code_unit, offset)); } // Safety: len invariant used here *(dst.add(offset)) = code_unit as $dst_unit; offset += 1; } None } }; } #[allow(unused_macros)] macro_rules! basic_latin_alu { ($name:ident, // safety invariant: use u8 for src/dest for ascii, and u16 for basic_latin $src_unit:ty, $dst_unit:ty, // safety invariant: stride function must munch ALU_STRIDE_SIZE*size(src_unit) bytes off o // write ALU_STRIDE_SIZE*size(dst_unit) bytes to dst $stride_fn:ident) => { /// Safety: src and dst must have len elements, src is valid for read, dst is valid for /// write /// Safety-usable invariant: will return Some() when it fails /// to convert. The first value will be a u8 that is > 127. #[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 { // Safety: until_alignment becomes the number of bytes we need to munch from src/dest until we a // We ensure basic-latin has the same alignment as ascii, starting with ascii since it is smalle let mut until_alignment = { // Check if the other unit aligns if we move the narrower unit // to alignment. // if ::core::mem::size_of::<$src_unit>() == ::core::mem::size_of::<$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 ::core::mem::size_of::<$src_unit>() < ::core::mem::size_of::<$dst_unit>() { // ascii_to_basic_latin let src_until_alignment = (ALU_ALIGNMENT - ((src as usize) & ALU_ALIGNMENT_MASK)) & ALU_ALIGNMENT_MASK; if (dst.wrapping_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.wrapping_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. // // Safety: This is the naïve code once again, for `until_alignment` bytes while until_alignment != 0 { let code_unit = *(src.add(offset)); if code_unit > 127 { // Safety: Upholds safety-usable invariant here return Some((code_unit, offset)); } *(dst.add(offset)) = code_unit as $dst_unit; // Safety: offset is the number of bytes copied so far offset += 1; until_alignment -= 1; } let len_minus_stride = len - ALU_STRIDE_SIZE; loop { if !$stride_fn( // Safety: These are known to be valid and aligned since we have at // least ALU_STRIDE_SIZE data in these buffers, and offset is the // number of elements copied so far, which according to the // until_alignment calculation above will cause both src and dst to be // aligned to usize after this add src.add(offset) as *const usize, dst.add(offset) as *mut usize, ) { break; } // Safety: offset continues to be the number of bytes copied so far, and // maintains usize alignment for the next loop iteration offset += ALU_STRIDE_SIZE; // Safety: This is `offset > len - stride. This loop will continue as long as // `offset <= len - stride`, which means there are `stride` bytes to still be read. if offset > len_minus_stride { break; } } } break; } // Safety: This is the naïve code once again, for leftover bytes while offset < len { // Safety: len invariant used here let code_unit = *(src.add(offset)); if code_unit > 127 { // Safety: Upholds safety-usable invariant here return Some((code_unit, offset)); } // Safety: len invariant used here *(dst.add(offset)) = code_unit as $dst_unit; offset += 1; } None } }; } #[allow(unused_macros)] macro_rules! latin1_alu { // safety invariant: stride function must munch ALU_STRIDE_SIZE*size(src_unit) bytes off o // write ALU_STRIDE_SIZE*size(dst_unit) bytes to dst ($name:ident, $src_unit:ty, $dst_unit:ty, $stride_fn:ident) => { /// Safety: src and dst must have len elements, src is valid for read, dst is valid for /// write #[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 $dst_unit, len: usize) { let mut offset = 0usize; // This loop is only broken out of as a `goto` forward loop { // Safety: until_alignment becomes the number of bytes we need to munch from src/dest until we a // We ensure the UTF-16 side has the same alignment as the Latin-1 side, starting with Latin-1 si let mut until_alignment = { if ::core::mem::size_of::<$src_unit>() < ::core::mem::size_of::<$dst_unit>() { // unpack let src_until_alignment = (ALU_ALIGNMENT - ((src as usize) & ALU_ALIGNMENT_MASK)) & ALU_ALIGNMENT_MASK; if (dst.wrapping_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.wrapping_add(dst_until_alignment) as usize) & ALU_ALIGNMENT_MASK != 0 { break; } dst_until_alignment } }; if until_alignment + ALU_STRIDE_SIZE <= len { // Safety: This is the naïve code once again, for `until_alignment` bytes while until_alignment != 0 { let code_unit = *(src.add(offset)); *(dst.add(offset)) = code_unit as $dst_unit; // Safety: offset is the number of bytes copied so far offset += 1; until_alignment -= 1; } let len_minus_stride = len - ALU_STRIDE_SIZE; loop { $stride_fn( // Safety: These are known to be valid and aligned since we have at // least ALU_STRIDE_SIZE data in these buffers, and offset is the // number of elements copied so far, which according to the // until_alignment calculation above will cause both src and dst to be // aligned to usize after this add src.add(offset) as *const usize, dst.add(offset) as *mut usize, ); // Safety: offset continues to be the number of bytes copied so far, and // maintains usize alignment for the next loop iteration offset += ALU_STRIDE_SIZE; // Safety: This is `offset > len - stride. This loop will continue as long as // `offset <= len - stride`, which means there are `stride` bytes to still be read. if offset > len_minus_stride { break; } } } break; } // Safety: This is the naïve code once again, for leftover bytes while offset < len { // Safety: len invariant used here 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, // Safety: This function must require aligned src/dest that are valid for reading/writing SIM $stride_both_aligned:ident, // Safety: This function must require aligned/unaligned src/dest that are valid for reading/ $stride_src_aligned:ident, // Safety: This function must require unaligned/aligned src/dest that are valid for reading/ $stride_dst_aligned:ident, // Safety: This function must require unaligned src/dest that are valid for reading/writing S $stride_neither_aligned:ident ) => { /// Safety: src/dst must be valid for reads/writes of `len` elements of their units. /// /// Safety-usable invariant: will return Some() when it encounters non-ASCII, with the first /// guaranteed to be non-ASCII (> 127), and the second being the offset where it is found #[inline(always)] pub unsafe fn $name( src: *const $src_unit, dst: *mut $dst_unit, len: usize, ) -> Option<($src_unit, usize)> { let mut offset = 0usize; // Safety: if this check succeeds we're valid for reading/writing at least `SIMD_STRIDE_SIZE 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; // Safety: checking whether src is aligned if ((src as usize) & SIMD_ALIGNMENT_MASK) == 0 { // Safety: Checking whether dst is aligned if dst_masked == 0 { loop { // Safety: We're valid to read/write SIMD_STRIDE_SIZE elements and have the appropriate alig if !$stride_both_aligned(src.add(offset), dst.add(offset)) { break; } offset += SIMD_STRIDE_SIZE; // Safety: This is `offset > len - SIMD_STRIDE_SIZE` which means we always have at least `SIMD_ST if offset > len_minus_stride { break; } } } else { loop { // Safety: We're valid to read/write SIMD_STRIDE_SIZE elements and have the appropriate alig if !$stride_src_aligned(src.add(offset), dst.add(offset)) { break; } offset += SIMD_STRIDE_SIZE; // Safety: This is `offset > len - SIMD_STRIDE_SIZE` which means we always have at least `SIMD_ST if offset > len_minus_stride { break; } } } } else { if dst_masked == 0 { loop { // Safety: We're valid to read/write SIMD_STRIDE_SIZE elements and have the appropriate alig if !$stride_dst_aligned(src.add(offset), dst.add(offset)) { break; } offset += SIMD_STRIDE_SIZE; // Safety: This is `offset > len - SIMD_STRIDE_SIZE` which means we always have at least `SIMD_ST if offset > len_minus_stride { break; } } } else { loop { // Safety: We're valid to read/write SIMD_STRIDE_SIZE elements and have the appropriate alig if !$stride_neither_aligned(src.add(offset), dst.add(offset)) { break; } offset += SIMD_STRIDE_SIZE; // Safety: This is `offset > len - SIMD_STRIDE_SIZE` which means we always have at least `SIMD_ST if offset > len_minus_stride { break; } } } } } while offset < len { // Safety: uses len invariant here and below let code_unit = *(src.add(offset)); if code_unit > 127 { // Safety: upholds safety-usable invariant 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, // Safety: This function must require aligned src/dest that are valid for reading/writing SIM $stride_both_aligned:ident, // Safety: This function must require aligned/unaligned src/dest that are valid for reading/ $stride_src_aligned:ident, // Safety: This function must require unaligned src/dest that are valid for reading/writing S $stride_neither_aligned:ident, // Safety: This function must require aligned src/dest that are valid for reading/writing 2*S $double_stride_both_aligned:ident, // Safety: This function must require aligned/unaligned src/dest that are valid for reading/ $double_stride_src_aligned:ident ) => { /// Safety: src/dst must be valid for reads/writes of `len` elements of their units. /// /// Safety-usable invariant: will return Some() when it encounters non-ASCII, with the first /// guaranteed to be non-ASCII (> 127), and the second being the offset where it is found #[inline pub unsafe fn $name( src: *const $src_unit, dst: *mut $dst_unit, len: usize, ) -> Option<($src_unit, usize)> { let unit_size = ::core::mem::size_of::<$src_unit>(); let mut offset = 0usize; // This loop is only broken out of as a goto forward without // actually looping 'outer: loop { // Safety: if this check succeeds we're valid for reading/writing at least `SIMD_STRIDE_SIZE if SIMD_STRIDE_SIZE <= len { // First, process one unaligned // Safety: this is safe to call since we're valid for this read/write if !$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. // // Safety: this correctly calculates the number of src_units that need to be read before the rem // This is less that SIMD_ALIGNMENT, which is also SIMD_STRIDE_SIZE (as documented) let until_alignment = ((SIMD_ALIGNMENT - ((src.add(offset) as usize) & SIMD_ALIGNMENT_MASK)) & SIMD_ALIGNMENT_MASK) / unit_size; // Safety: 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. // // Safety: if this check succeeds we're valid for reading/writing at least `2 * SIMD_STRIDE_SI // The extra SIMD_STRIDE_SIZE in the condition is because `offset` is already `SIMD_STRIDE_S if until_alignment + (SIMD_STRIDE_SIZE * 3) <= len { if until_alignment != 0 { // Safety: this is safe to call since we're valid for this read/write (and more), and don't care a // This will copy over bytes that get decoded twice since it's not incrementing `offset` by SIMD if !$stride_neither_aligned(src.add(offset), dst.add(offset)) { break; } offset += until_alignment; } // Safety: At this point we're valid for reading/writing 2*SIMD_STRIDE_SIZE elements // Safety: Now `offset` is aligned for `src` let len_minus_stride_times_two = len - (SIMD_STRIDE_SIZE * 2); // Safety: This is whether dst is aligned let dst_masked = (dst.add(offset) as usize) & SIMD_ALIGNMENT_MASK; if dst_masked == 0 { loop { // Safety: both are aligned, we can call the aligned function. We're valid for reading/writing // and the loop break condition below if let Some(advance) = $double_stride_both_aligned(src.add(offset), dst.add(offset)) { offset += advance; let code_unit = *(src.add(offset)); // Safety: uses safety-usable invariant on ascii_to_ascii_simd_double_stride to return // guaranteed non-ascii return Some((code_unit, offset)); } offset += SIMD_STRIDE_SIZE * 2; // Safety: This is `offset > len - 2 * SIMD_STRIDE_SIZE` which means we always have at least `2 * SIM if offset > len_minus_stride_times_two { break; } } // Safety: We're valid for reading/writing one more, and can still assume alignment if offset + SIMD_STRIDE_SIZE <= len { if !$stride_both_aligned(src.add(offset), dst.add(offset)) { break 'outer; } offset += SIMD_STRIDE_SIZE; } } else { loop { // Safety: only src is aligned here. We're valid for reading/writing double stride from the ini // and the loop break condition below if let Some(advance) = $double_stride_src_aligned(src.add(offset), dst.add(offset)) { offset += advance; let code_unit = *(src.add(offset)); // Safety: uses safety-usable invariant on ascii_to_ascii_simd_double_stride to return // guaranteed non-ascii return Some((code_unit, offset)); } offset += SIMD_STRIDE_SIZE * 2; // Safety: This is `offset > len - 2 * SIMD_STRIDE_SIZE` which means we always have at least `2 * SIM if offset > len_minus_stride_times_two { break; } } // Safety: We're valid for reading/writing one more, and can still assume alignment if offset + SIMD_STRIDE_SIZE <= len { if !$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 { // Safety: The check above ensures we're allowed to read/write this, and we don't use alignment if !$stride_neither_aligned(src.add(offset), dst.add(offset)) { break; } offset += SIMD_STRIDE_SIZE; if offset + SIMD_STRIDE_SIZE <= len { // Safety: The check above ensures we're allowed to read/write this, and we don't use alignment if !$stride_neither_aligned(src.add(offset), dst.add(offset)) { break; } offset += SIMD_STRIDE_SIZE; } } } } break 'outer; } while offset < len { // Safety: relies straightforwardly on the `len` invariant let code_unit = *(src.add(offset)); if code_unit > 127 { // Safety-usable invariant upheld here 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, // Safety: This function must require aligned src/dest that are valid for reading/writing SIM $stride_both_aligned:ident, // Safety: This function must require aligned/unaligned src/dest that are valid for reading/ $stride_src_aligned:ident, // Safety: This function must require unaligned/aligned src/dest that are valid for reading/ $stride_dst_aligned:ident, // Safety: This function must require unaligned src/dest that are valid for reading/writing S $stride_neither_aligned:ident ) => { /// Safety: src/dst must be valid for reads/writes of `len` elements of their units. #[inline(always)] pub unsafe fn $name(src: *const $src_unit, dst: *mut $dst_unit, len: usize) { let mut offset = 0usize; // Safety: if this check succeeds we're valid for reading/writing at least `SIMD_STRIDE_SIZE if SIMD_STRIDE_SIZE <= len { let len_minus_stride = len - SIMD_STRIDE_SIZE; // Whether dst is aligned let dst_masked = (dst as usize) & SIMD_ALIGNMENT_MASK; // Whether src is aligned if ((src as usize) & SIMD_ALIGNMENT_MASK) == 0 { if dst_masked == 0 { loop { // Safety: Both were aligned, we can use the aligned function $stride_both_aligned(src.add(offset), dst.add(offset)); offset += SIMD_STRIDE_SIZE; // Safety: This is `offset > len - SIMD_STRIDE_SIZE`, which means in the next iteration we're val // reading/writing at least SIMD_STRIDE_SIZE elements. if offset > len_minus_stride { break; } } } else { loop { // Safety: src was aligned, dst was not $stride_src_aligned(src.add(offset), dst.add(offset)); offset += SIMD_STRIDE_SIZE; // Safety: This is `offset > len - SIMD_STRIDE_SIZE`, which means in the next iteration we're val // reading/writing at least SIMD_STRIDE_SIZE elements. if offset > len_minus_stride { break; } } } } else { if dst_masked == 0 { loop { // Safety: src was aligned, dst was not $stride_dst_aligned(src.add(offset), dst.add(offset)); offset += SIMD_STRIDE_SIZE; // Safety: This is `offset > len - SIMD_STRIDE_SIZE`, which means in the next iteration we're val // reading/writing at least SIMD_STRIDE_SIZE elements. if offset > len_minus_stride { break; } } } else { loop { // Safety: Neither were aligned $stride_neither_aligned(src.add(offset), dst.add(offset)); offset += SIMD_STRIDE_SIZE; // Safety: This is `offset > len - SIMD_STRIDE_SIZE`, which means in the next iteration we're val // reading/writing at least SIMD_STRIDE_SIZE elements. if offset > len_minus_stride { break; } } } } } while offset < len { // Safety: relies straightforwardly on the `len` invariant 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, // Safety: This function must require aligned src/dest that are valid for reading/writing SIM $stride_both_aligned:ident, // Safety: This function must require aligned/unaligned src/dest that are valid for reading/ $stride_src_aligned:ident, // Safety: This function must require unaligned/aligned src/dest that are valid for reading/ $stride_dst_aligned:ident, // Safety: This function must require unaligned src/dest that are valid for reading/writing S $stride_neither_aligned:ident ) => { /// Safety: src/dst must be valid for reads/writes of `len` elements of their units. #[inline(always)] pub unsafe fn $name(src: *const $src_unit, dst: *mut $dst_unit, len: usize) { let unit_size = ::core::mem::size_of::<$src_unit>(); let mut offset = 0usize; // Safety: if this check succeeds we're valid for reading/writing at least `SIMD_STRIDE_SIZE if SIMD_STRIDE_SIZE <= len { // Safety: this correctly calculates the number of src_units that need to be read before the rem // This is by definition less than SIMD_STRIDE_SIZE. let mut until_alignment = ((SIMD_STRIDE_SIZE - ((src as usize) & SIMD_ALIGNMENT_MASK)) & SIMD_ALIGNMENT_MASK) / unit_size; while until_alignment != 0 { // Safety: This is a straightforward copy, since until_alignment is < SIMD_STRIDE_SIZE < len, th *(dst.add(offset)) = *(src.add(offset)) as $dst_unit; offset += 1; until_alignment -= 1; } // Safety: here offset will be `until_alignment`, i.e. enough to align `src`. let len_minus_stride = len - SIMD_STRIDE_SIZE; // Safety: if this check succeeds we're valid for reading/writing at least `2 * SIMD_STRIDE_SI if offset + SIMD_STRIDE_SIZE * 2 <= len { let len_minus_stride_times_two = len_minus_stride - SIMD_STRIDE_SIZE; // Safety: at this point src is known to be aligned at offset, dst is not. if (dst.add(offset) as usize) & SIMD_ALIGNMENT_MASK == 0 { loop { // Safety: We checked alignment of dst above, we can use the alignment functions. We're allowed $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; // Safety: This is `offset > len - 2 * SIMD_STRIDE_SIZE` which means we always have at least `2 * SIM if offset > len_minus_stride_times_two { break; } } } else { loop { // Safety: we ensured alignment of src already. $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; // Safety: This is `offset > len - 2 * SIMD_STRIDE_SIZE` which means we always have at least `2 * SIM if offset > len_minus_stride_times_two { break; } } } } // Safety: This is `offset > len - SIMD_STRIDE_SIZE` which means we are valid to munch SIMD_STRID if offset < len_minus_stride { $stride_src_aligned(src.add(offset), dst.add(offset)); offset += SIMD_STRIDE_SIZE; } } while offset < len { // Safety: uses len invariant here and below 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 $dst_unit; offset += 1; } } }; } #[allow(unused_macros)] macro_rules! ascii_simd_unalign { // Safety: stride_neither_aligned must be a function that requires src/dest be valid for unal ($name:ident, $src_unit:ty, $dst_unit:ty, $stride_neither_aligned:ident) => { /// Safety: src and dst must be valid for reads/writes of len elements of type src_unit/dst_uni /// /// Safety-usable invariant: will return Some() when it encounters non-ASCII, with the first /// guaranteed to be non-ASCII (> 127), and the second being the offset where it is found #[inline(always)] pub unsafe fn $name( src: *const $src_unit, dst: *mut $dst_unit, len: usize, ) -> Option<($src_unit, usize)> { let mut offset = 0usize; // Safety: if this check succeeds we're valid for reading/writing at least `stride` elements. if SIMD_STRIDE_SIZE <= len { let len_minus_stride = len - SIMD_STRIDE_SIZE; loop { // Safety: We know we're valid for `stride` reads/writes, so we can call this function. We don't if !$stride_neither_aligned(src.add(offset), dst.add(offset)) { break; } offset += SIMD_STRIDE_SIZE; // This is `offset > len - stride` which means we always have at least `stride` elements to munch ne if offset > len_minus_stride { break; } } } while offset < len { // Safety: Uses len invariant here and below let code_unit = *(src.add(offset)); if code_unit > 127 { // Safety-usable invariant upheld here return Some((code_unit, offset)); } *(dst.add(offset)) = code_unit as $dst_unit; offset += 1; } None } }; } #[allow(unused_macros)] macro_rules! latin1_simd_unalign { // Safety: stride_neither_aligned must be a function that requires src/dest be valid for unal ($name:ident, $src_unit:ty, $dst_unit:ty, $stride_neither_aligned:ident) => { /// Safety: src and dst must be valid for unaligned reads/writes of len elements of type src_uni #[inline(always)] pub unsafe fn $name(src: *const $src_unit, dst: *mut $dst_unit, len: usize) { let mut offset = 0usize; // Safety: if this check succeeds we're valid for reading/writing at least `stride` elements. if SIMD_STRIDE_SIZE <= len { let len_minus_stride = len - SIMD_STRIDE_SIZE; loop { // Safety: We know we're valid for `stride` reads/writes, so we can call this function. We don't $stride_neither_aligned(src.add(offset), dst.add(offset)); offset += SIMD_STRIDE_SIZE; // This is `offset > len - stride` which means we always have at least `stride` elements to munch ne if offset > len_minus_stride { break; } } } while offset < len { // Safety: Uses len invariant here let code_unit = *(src.add(offset)); *(dst.add(offset)) = code_unit as $dst_unit; offset += 1; } } }; } #[allow(unused_macros)] macro_rules! ascii_to_ascii_simd_stride { // Safety: load/store must be valid for 16 bytes of read/write, which may be unaligned. (candid ($name:ident, $load:ident, $store:ident) => { /// Safety: src and dst must be valid for 16 bytes of read/write according to /// the $load/$store fn, which may allow for unaligned reads/writes or require /// alignment to either 16x8 or u8x16. #[inline(always)] pub unsafe fn $name(src: *const u8, dst: *mut u8) -> bool { let simd = $load(src); if !simd_is_ascii(simd) { return false; } $store(dst, simd); true } }; } #[allow(unused_macros)] macro_rules! ascii_to_ascii_simd_double_stride { // Safety: store must be valid for 32 bytes of write, which may be unaligned (candidates: `store ($name:ident, $store:ident) => { /// Safety: src must be valid for 32 bytes of aligned u8x16 read /// dst must be valid for 32 bytes of unaligned write according to /// the $store fn, which may allow for unaligned writes or require /// alignment to either 16x8 or u8x16. /// /// Safety-usable invariant: Returns Some(index) if the element at `index` is invalid ASCII #[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)) { // Safety: mask_ascii produces a mask of all the high bits. let mask_first = mask_ascii(first); if mask_first != 0 { // Safety: on little endian systems this will be the number of ascii bytes // before the first non-ascii, i.e. valid for indexing src // TODO SAFETY: What about big-endian systems? return Some(mask_first.trailing_zeros() as usize); } $store(dst.add(SIMD_STRIDE_SIZE), second); let mask_second = mask_ascii(second); // Safety: on little endian systems this will be the number of ascii bytes // before the first non-ascii, i.e. valid for indexing src return Some(SIMD_STRIDE_SIZE + mask_second.trailing_zeros() as usize); } $store(dst.add(SIMD_STRIDE_SIZE), second); None } }; } #[allow(unused_macros)] macro_rules! ascii_to_basic_latin_simd_stride { // Safety: load/store must be valid for 16 bytes of read/write, which may be unaligned. (candid ($name:ident, $load:ident, $store:ident) => { /// Safety: src and dst must be valid for 16/32 bytes of read/write according to /// the $load/$store fn, which may allow for unaligned reads/writes or require /// alignment to either 16x8 or u8x16. #[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); $store(dst.add(8), second); true } }; } #[allow(unused_macros)] macro_rules! ascii_to_basic_latin_simd_double_stride { // Safety: store must be valid for 16 bytes of write, which may be unaligned ($name:ident, $store:ident) => { /// Safety: src must be valid for 2*SIMD_STRIDE_SIZE bytes of aligned reads, /// aligned to either 16x8 or u8x16. /// dst must be valid for 2*SIMD_STRIDE_SIZE bytes of aligned or unaligned reads #[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); // Safety: divide by 2 since it's a u16 pointer $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); $store(dst.add(SIMD_STRIDE_SIZE + (SIMD_STRIDE_SIZE / 2)), d); None } }; } #[allow(unused_macros)] macro_rules! unpack_simd_stride { // Safety: load/store must be valid for 16 bytes of read/write, which may be unaligned. (candid ($name:ident, $load:ident, $store:ident) => { /// Safety: src and dst must be valid for 16 bytes of read/write according to /// the $load/$store fn, which may allow for unaligned reads/writes or require /// alignment to either 16x8 or u8x16. #[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); $store(dst.add(8), second); } }; } #[allow(unused_macros)] macro_rules! basic_latin_to_ascii_simd_stride { // Safety: load/store must be valid for 16 bytes of read/write, which may be unaligned. (candid ($name:ident, $load:ident, $store:ident) => { /// Safety: src and dst must be valid for 32/16 bytes of read/write according to /// the $load/$store fn, which may allow for unaligned reads/writes or require /// alignment to either 16x8 or u8x16. #[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) { $store(dst, simd_pack(first, second)); true } else { false } } }; } #[allow(unused_macros)] macro_rules! pack_simd_stride { // Safety: load/store must be valid for 16 bytes of read/write, which may be unaligned. (candid ($name:ident, $load:ident, $store:ident) => { /// Safety: src and dst must be valid for 32/16 bytes of read/write according to /// the $load/$store fn, which may allow for unaligned reads/writes or require /// alignment to either 16x8 or u8x16. #[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; // Safety for stride macros: We stick to the load8_aligned/etc family of functions. We consist // neither_unaligned variants using only unaligned inputs. ascii_to_ascii_simd_stride!(ascii_to_ascii_stride_neither_aligned, load16_unalign ascii_to_basic_latin_simd_stride!(ascii_to_basic_latin_stride_neither_aligned, lo unpack_simd_stride!(unpack_stride_neither_aligned, load16_unaligned, store8_unalig basic_latin_to_ascii_simd_stride!(basic_latin_to_ascii_stride_neither_aligned, lo pack_simd_stride!(pack_stride_neither_aligned, load8_unaligned, store16_unaligned) // Safety for conversion macros: We use the unalign macro with unalign functions above. All str // by stride macros that universally munch a single SIMD_STRIDE_SIZE worth of elements. 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_neit ascii_simd_unalign!(basic_latin_to_ascii, u16, u8, basic_latin_to_ascii_stride_neit 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 = "neo // 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; // Safety for stride macros: We stick to the load8_aligned/etc family of functions. We consist // aligned/unaligned functions according to src/dst being aligned/unaligned ascii_to_ascii_simd_stride!(ascii_to_ascii_stride_both_aligned, load16_aligned, st ascii_to_ascii_simd_stride!(ascii_to_ascii_stride_src_aligned, load16_aligned, sto ascii_to_ascii_simd_stride!(ascii_to_ascii_stride_dst_aligned, load16_unaligned, s ascii_to_ascii_simd_stride!(ascii_to_ascii_stride_neither_aligned, load16_unalign ascii_to_basic_latin_simd_stride!(ascii_to_basic_latin_stride_both_aligned, load1 ascii_to_basic_latin_simd_stride!(ascii_to_basic_latin_stride_src_aligned, load16 ascii_to_basic_latin_simd_stride!(ascii_to_basic_latin_stride_dst_aligned, load16 ascii_to_basic_latin_simd_stride!(ascii_to_basic_latin_stride_neither_aligned, lo 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_unalig basic_latin_to_ascii_simd_stride!(basic_latin_to_ascii_stride_both_aligned, load8 basic_latin_to_ascii_simd_stride!(basic_latin_to_ascii_stride_src_aligned, load8_ basic_latin_to_ascii_simd_stride!(basic_latin_to_ascii_stride_dst_aligned, load8_ basic_latin_to_ascii_simd_stride!(basic_latin_to_ascii_stride_neither_aligned, lo 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) // Safety for conversion macros: We use the correct pattern of both/src/dst/neither here. All // by stride macros that universally munch a single SIMD_STRIDE_SIZE worth of elements. ascii_simd_check_align!(ascii_to_ascii, u8, u8, ascii_to_ascii_stride_both_aligned, ascii_simd_check_align!(ascii_to_basic_latin, u8, u16, ascii_to_basic_latin_stride_ ascii_simd_check_align!(basic_latin_to_ascii, u16, u8, basic_latin_to_ascii_stride_ latin1_simd_check_align!(unpack_latin1, u8, u16, unpack_stride_both_aligned, unpack_ latin1_simd_check_align!(pack_latin1, u16, u8, pack_stride_both_aligned, pack_stride } 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; /// Safety-usable invariant: This should be identical to SIMD_STRIDE_SIZE (used by ascii_si pub const SIMD_ALIGNMENT: usize = 16; pub const MAX_STRIDE_SIZE: usize = 16; pub const SIMD_ALIGNMENT_MASK: usize = 15; // Safety for stride macros: We stick to the load8_aligned/etc family of functions. We consist // aligned/unaligned functions according to src/dst being aligned/unaligned ascii_to_ascii_simd_double_stride!(ascii_to_ascii_simd_double_stride_both_aligne ascii_to_ascii_simd_double_stride!(ascii_to_ascii_simd_double_stride_src_aligned ascii_to_basic_latin_simd_double_stride!(ascii_to_basic_latin_simd_double_stride ascii_to_basic_latin_simd_double_stride!(ascii_to_basic_latin_simd_double_stride ascii_to_ascii_simd_stride!(ascii_to_ascii_stride_both_aligned, load16_aligned, st ascii_to_ascii_simd_stride!(ascii_to_ascii_stride_src_aligned, load16_aligned, sto ascii_to_ascii_simd_stride!(ascii_to_ascii_stride_neither_aligned, load16_unalign ascii_to_basic_latin_simd_stride!(ascii_to_basic_latin_stride_both_aligned, load1 ascii_to_basic_latin_simd_stride!(ascii_to_basic_latin_stride_src_aligned, load16 ascii_to_basic_latin_simd_stride!(ascii_to_basic_latin_stride_neither_aligned, lo 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 basic_latin_to_ascii_simd_stride!(basic_latin_to_ascii_stride_src_aligned, load8_ basic_latin_to_ascii_simd_stride!(basic_latin_to_ascii_stride_dst_aligned, load8_ basic_latin_to_ascii_simd_stride!(basic_latin_to_ascii_stride_neither_aligned, lo pack_simd_stride!(pack_stride_both_aligned, load8_aligned, store16_aligned); pack_simd_stride!(pack_stride_src_aligned, load8_aligned, store16_unaligned); // Safety for conversion macros: We use the correct pattern of both/src/dst/neither/double_ // by stride macros that universally munch a single SIMD_STRIDE_SIZE worth of elements. ascii_simd_check_align_unrolled!(ascii_to_ascii, u8, u8, ascii_to_ascii_stride_both ascii_simd_check_align_unrolled!(ascii_to_basic_latin, u8, u16, ascii_to_basic_lati ascii_simd_check_align!(basic_latin_to_ascii, u16, u8, basic_latin_to_ascii_stride_ latin1_simd_check_align_unrolled!(unpack_latin1, u8, u16, unpack_stride_both_aligne latin1_simd_check_align_unrolled!(pack_latin1, u16, u8, pack_stride_both_aligned, pa } else if #[cfg(all(target_endian = "little", target_pointer_width = "64"))] { // Aligned ALU word, little-endian, 64-bit /// Safety invariant: this is the amount of bytes consumed by /// unpack_alu. This will be twice the pointer width, as it consumes two usizes. /// This is also the number of bytes produced by pack_alu. /// This is also the number of u16 code units produced/consumed by unpack_alu/pack_alu respec pub const ALU_STRIDE_SIZE: usize = 16; pub const MAX_STRIDE_SIZE: usize = 16; // Safety invariant: this is the pointer width in bytes pub const ALU_ALIGNMENT: usize = 8; // Safety invariant: this is a mask for getting the bits of a pointer not aligned to ALU_ALIGNMEN pub const ALU_ALIGNMENT_MASK: usize = 7; /// Safety: dst must point to valid space for writing four `usize`s #[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); // Safety: fn invariant used here *dst = first; *(dst.add(1)) = second; *(dst.add(2)) = third; *(dst.add(3)) = fourth; } /// Safety: dst must point to valid space for writing two `usize`s #[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); // Safety: fn invariant used here *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 /// Safety invariant: this is the amount of bytes consumed by /// unpack_alu. This will be twice the pointer width, as it consumes two usizes. /// This is also the number of bytes produced by pack_alu. /// This is also the number of u16 code units produced/consumed by unpack_alu/pack_alu respec pub const ALU_STRIDE_SIZE: usize = 8; pub const MAX_STRIDE_SIZE: usize = 8; // Safety invariant: this is the pointer width in bytes pub const ALU_ALIGNMENT: usize = 4; // Safety invariant: this is a mask for getting the bits of a pointer not aligned to ALU_ALIGNMEN pub const ALU_ALIGNMENT_MASK: usize = 3; /// Safety: dst must point to valid space for writing four `usize`s #[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); // Safety: fn invariant used here *dst = first; *(dst.add(1)) = second; *(dst.add(2)) = third; *(dst.add(3)) = fourth; } /// Safety: dst must point to valid space for writing two `usize`s #[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); // Safety: fn invariant used here *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 /// Safety invariant: this is the amount of bytes consumed by /// unpack_alu. This will be twice the pointer width, as it consumes two usizes. /// This is also the number of bytes produced by pack_alu. /// This is also the number of u16 code units produced/consumed by unpack_alu/pack_alu respec pub const ALU_STRIDE_SIZE: usize = 16; pub const MAX_STRIDE_SIZE: usize = 16; // Safety invariant: this is the pointer width in bytes pub const ALU_ALIGNMENT: usize = 8; // Safety invariant: this is a mask for getting the bits of a pointer not aligned to ALU_ALIGNMEN pub const ALU_ALIGNMENT_MASK: usize = 7; /// Safety: dst must point to valid space for writing four `usize`s #[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); // Safety: fn invariant used here *dst = first; *(dst.add(1)) = second; *(dst.add(2)) = third; *(dst.add(3)) = fourth; } /// Safety: dst must point to valid space for writing two `usize`s #[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); // Safety: fn invariant used here *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 /// Safety invariant: this is the amount of bytes consumed by /// unpack_alu. This will be twice the pointer width, as it consumes two usizes. /// This is also the number of bytes produced by pack_alu. /// This is also the number of u16 code units produced/consumed by unpack_alu/pack_alu respec pub const ALU_STRIDE_SIZE: usize = 8; pub const MAX_STRIDE_SIZE: usize = 8; // Safety invariant: this is the pointer width in bytes pub const ALU_ALIGNMENT: usize = 4; // Safety invariant: this is a mask for getting the bits of a pointer not aligned to ALU_ALIGNMEN pub const ALU_ALIGNMENT_MASK: usize = 3; /// Safety: dst must point to valid space for writing four `usize`s #[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); // Safety: fn invariant used here *dst = first; *(dst.add(1)) = second; *(dst.add(2)) = third; *(dst.add(3)) = fourth; } /// Safety: dst must point to valid space for writing two `usize`s #[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); // Safety: fn invariant used here *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! { // Safety-usable invariant: this counts the zeroes from the "first byte" of utf-8 data packed i // with the target endianness 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")) /// Safety-usable invariant: Will return the value and position of the first non-ASCII byte in /// In other words, the first element of the Some is always `> 127` #[inline(always)] pub fn validate_ascii(slice: &[u8]) -> Option<(u8, usize)> { let src = slice.as_ptr(); let len = slice.len(); let mut offset = 0usize; // Safety: if this check succeeds we're valid for reading/writing at least `stride` elements. if SIMD_STRIDE_SIZE <= len { let len_minus_stride = len - SIMD_STRIDE_SIZE; loop { // Safety: src at offset is valid for a `SIMD_STRIDE_SIZE` read let simd = unsafe { load16_unaligned(src.add(offset)) }; if !simd_is_ascii(simd) { break; } offset += SIMD_STRIDE_SIZE; // This is `offset > len - SIMD_STRIDE_SIZE` which means we always have at least `SIMD_STRIDE_SI if offset > len_minus_stride { break; } } } while offset < len { let code_unit = slice[offset]; if code_unit > 127 { // Safety: Safety-usable invariant upheld here return Some((code_unit, offset)); } offset += 1; } None } } else if #[cfg(all(feature = "simd-accel", target_feature = "sse2"))] { /// Safety-usable invariant: will return Some() when it encounters non-ASCII, with the first /// guaranteed to be non-ASCII (> 127), and the second being the offset where it is found #[inline(always)] pub fn validate_ascii(slice: &[u8]) -> Option<(u8, usize)> { let src = slice.as_ptr(); let len = slice.len(); let mut offset = 0usize; // Safety: if this check succeeds we're valid for reading at least `stride` elements. if SIMD_STRIDE_SIZE <= len { // First, process one unaligned vector // Safety: src is valid for a `SIMD_STRIDE_SIZE` read 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; // Safety: Now that offset has changed we don't yet know how much it is valid for // 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. // Safety: this correctly calculates the number of src_units that need to be read before the rem // This is by definition less than SIMD_ALIGNMENT, which is defined to be equal to SIMD_STRIDE_ let until_alignment = unsafe { (SIMD_ALIGNMENT - ((src.add(offset) as usize) & SIMD_ALI // 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. // // Safety: if this check succeeds we're valid for reading at least `2 * SIMD_STRIDE_SIZE` eleme // The extra SIMD_STRIDE_SIZE in the condition is because `offset` is already `SIMD_STRIDE_S if until_alignment + (SIMD_STRIDE_SIZE * 3) <= len { if until_alignment != 0 { // Safety: this is safe to call since we're valid for this read (and more), and don't care about al // This will copy over bytes that get decoded twice since it's not incrementing `offset` by SIMD 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; } // Safety: At this point we're valid for reading 2*SIMD_STRIDE_SIZE elements // Safety: Now `offset` is aligned for `src` let len_minus_stride_times_two = len - (SIMD_STRIDE_SIZE * 2); loop { // Safety: We were valid for this read, and were aligned. 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) { // Safety: mask_ascii produces a mask of all the high bits. let mask_first = mask_ascii(first); if mask_first != 0 { // Safety: on little endian systems this will be the number of ascii bytes // before the first non-ascii, i.e. valid for indexing src // TODO SAFETY: What about big-endian systems? offset += mask_first.trailing_zeros() as usize; } else { let mask_second = mask_ascii(second); // Safety: on little endian systems this will be the number of ascii bytes // before the first non-ascii, i.e. valid for indexing src offset += SIMD_STRIDE_SIZE + mask_second.trailing_zeros() as usize; } // Safety: We know this is non-ASCII, and can uphold the safety-usable invariant here let non_ascii = unsafe { *src.add(offset) }; return Some((non_ascii, offset)); } offset += SIMD_STRIDE_SIZE * 2; // Safety: This is `offset > len - 2 * SIMD_STRIDE_SIZE` which means we always have at least `2 * SIM if offset > len_minus_stride_times_two { break; } } // Safety: if this check succeeds we're valid for reading at least `SIMD_STRIDE_SIZE` if offset + SIMD_STRIDE_SIZE <= len { // Safety: We were valid for this read, and were aligned. let simd = unsafe { load16_aligned(src.add(offset)) }; // Safety: mask_ascii produces a mask of all the high bits. let mask = mask_ascii(simd); if mask != 0 { // Safety: on little endian systems this will be the number of ascii bytes // before the first non-ascii, i.e. valid for indexing src offset += mask.trailing_zeros() as usize; let non_ascii = unsafe { *src.add(offset) }; // Safety: We know this is non-ASCII, and can uphold the safety-usable invariant here return Some((non_ascii, offset)); } offset += SIMD_STRIDE_SIZE; } } else { // Safety: this is the unaligned branch // At most two iterations, so unroll // Safety: if this check succeeds we're valid for reading at least `SIMD_STRIDE_SIZE` if offset + SIMD_STRIDE_SIZE <= len { // Safety: We're valid for this read but must use an unaligned read 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) }; // Safety-usable invariant upheld here (same as above) return Some((non_ascii, offset)); } offset += SIMD_STRIDE_SIZE; // Safety: if this check succeeds we're valid for reading at least `SIMD_STRIDE_SIZE` if offset + SIMD_STRIDE_SIZE <= len { // Safety: We're valid for this read but must use an unaligned read 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) }; // Safety-usable invariant upheld here (same as above) return Some((non_ascii, offset)); } offset += SIMD_STRIDE_SIZE; } } } } while offset < len { // Safety: relies straightforwardly on the `len` invariant let code_unit = unsafe { *(src.add(offset)) }; if code_unit > 127 { // Safety-usable invariant upheld here return Some((code_unit, offset)); } offset += 1; } None } } else { // Safety-usable invariant: returns byte index of first non-ascii byte #[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 { // Both are ascii, invariant upheld return None; } if word_masked != 0 { let zeros = count_zeros(word_masked); // `zeros` now contains 0 to 7 (for the seven bits of masked ASCII in little endian, // or up to 7 bits of non-ASCII in big endian if the first byte is 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; // Safety-usable invariant upheld here return Some(num_ascii); } let zeros = count_zeros(second_masked); // `zeros` now contains 0 to 7 (for the seven bits of masked ASCII in little endian, // or up to 7 bits of non-ASCII in big endian if the first byte is 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; // Safety-usable invariant upheld here Some(ALU_ALIGNMENT + num_ascii) } /// Safety: `src` must be valid for the reads of two `usize`s /// /// Safety-usable invariant: will return byte index of first non-ascii byte #[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) } /// Safety-usable invariant: will return Some() when it encounters non-ASCII, with the first /// guaranteed to be non-ASCII (> 127), and the second being the offset where it is found #[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)) & // Safety: If this check fails we're valid to read `until_alignment + ALU_STRIDE_SIZE` elemen if until_alignment + ALU_STRIDE_SIZE <= len { while until_alignment != 0 { let code_unit = slice[offset]; if code_unit > 127 { // Safety-usable invairant upheld here return Some((code_unit, offset)); } offset += 1; until_alignment -= 1; } // Safety: At this point we have read until_alignment elements and // are valid for `ALU_STRIDE_SIZE` more. let len_minus_stride = len - ALU_STRIDE_SIZE; loop { // Safety: we were valid for this read let ptr = unsafe { src.add(offset) as *const usize }; if let Some(num_ascii) = unsafe { validate_ascii_stride(ptr) } { offset += num_ascii; // Safety-usable invairant upheld here using the invariant from validate_ascii_stride() return Some((unsafe { *(src.add(offset)) }, offset)); } offset += ALU_STRIDE_SIZE; // Safety: This is `offset > ALU_STRIDE_SIZE` which means we always have at least `2 * ALU_STRIDE if offset > len_minus_stride { break; } } } while offset < len { let code_unit = slice[offset]; if code_unit > 127 { // Safety-usable invairant upheld here return Some((code_unit, offset)); } offset += 1; } None } } } cfg_if! { if #[cfg(all(feature = "simd-accel", any(target_feature = "sse2", all(target_endian = "li } else if #[cfg(all(feature = "simd-accel", target_endian = "little", target_feature = "neo // 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 { // Safety: src points to two valid `usize`s, dst points to four valid `usize`s #[inline(always)] unsafe fn unpack_latin1_stride_alu(src: *const usize, dst: *mut usize) { // Safety: src safety invariant used here let word = *src; let second_word = *(src.add(1)); // Safety: dst safety invariant passed down unpack_alu(word, second_word, dst); } // Safety: src points to four valid `usize`s, dst points to two valid `usize`s #[inline(always)] unsafe fn pack_latin1_stride_alu(src: *const usize, dst: *mut usize) { // Safety: src safety invariant used here let first = *src; let second = *(src.add(1)); let third = *(src.add(2)); let fourth = *(src.add(3)); // Safety: dst safety invariant passed down pack_alu(first, second, third, fourth, dst); } // Safety: src points to two valid `usize`s, dst points to four valid `usize`s #[inline(always)] unsafe fn ascii_to_basic_latin_stride_alu(src: *const usize, dst: *mut usize) -> bool { // Safety: src safety invariant used here 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; } // Safety: dst safety invariant passed down unpack_alu(word, second_word, dst); true } // Safety: src points four valid `usize`s, dst points to two valid `usize`s #[inline(always)] unsafe fn basic_latin_to_ascii_stride_alu(src: *const usize, dst: *mut usize) -> bool { // Safety: src safety invariant used here 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_LA return false; } // Safety: dst safety invariant passed down pack_alu(first, second, third, fourth, dst); true } // Safety: src, dst both point to two valid `usize`s each // Safety-usable invariant: Will return byte index of first non-ascii byte. #[inline(always)] unsafe fn ascii_to_ascii_stride(src: *const usize, dst: *mut usize) -> Option<usize> { // Safety: src safety invariant used here let word = *src; let second_word = *(src.add(1)); // Safety: src safety invariant used here *dst = word; *(dst.add(1)) = second_word; // Relies on safety-usable invariant here 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); // Safety invariant upheld: ascii_to_ascii_stride will return byte index of first non-ascii 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(all(test, feature = "alloc"))] mod tests { use super::*; use alloc::vec::Vec; 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); } [0.73QuellennavigatorsProjekt 2026-04-26] |
2026-05-26