Rollup merge of #68232 - Mark-Simulacrum:unicode-tables, r=joshtriplett

Optimize size/speed of Unicode datasets

The overall implementation has the same general idea as the prior approach,
which was based on a compressed trie structure, but modified to use less space
(and, coincidentally, be an overall performance improvement).

Sizes | Old | New | New/current
-- | -- | -- | --
Alphabetic | 4616 | 2982 | 64.60%
Case_Ignorable | 3144 | 2112 | 67.18%
Cased | 2376 | 934 | 39.31%
Cc | 19 | 43 | 226.32%
Grapheme_Extend | 3072 | 1734 | 56.45%
Lowercase | 2328 | 985 | 42.31%
N | 2648 | 1239 | 46.79%
Uppercase | 1978 | 934 | 47.22%
White_Space | 241 | 140 | 58.09%
  |   |   |
Total | 20422 | 11103 | 54.37%

This table shows the size of the old and new tables in bytes. The most important
of these tables is "Grapheme_Extend", as it is present in essentially all Rust
programs due to being called from `str`'s Debug impl (`char::escape_debug`). In
a representative case given by this [blog post] for the embedded world, the
shrinking in this PR shrinks the final binary by 1,604 bytes, from 14,440 to
12,836.

The performance of these new tables, based on the (rough) benchmark of linearly
scanning the entire valid set of chars, querying for each `is_*`, is roughly
~50% better, though in some cases is either on par or slightly (3-5%) worse. In
practice, I believe the size benefits of this PR are the main concern. The new
implementation has been tested to be equivalent to the current nightly in terms
of returned values on the set of valid chars.

A (relatively) high-level explanation of the specific compression scheme used
can be found [in the generator].

This is split into three commits -- the first adds the generator which produces
the Rust code for the tables, the second adds support code for the lookup, and
the third actually swaps the current implementation out for the new one.

[blog post]: https://jamesmunns.com/blog/fmt-unreasonably-expensive/
[in the generator]: https://github.com/Mark-Simulacrum/rust/blob/unicode-tables/src/tools/unicode-table-generator/src/raw_emitter.rs
This commit is contained in:
Dylan DPC 2020-01-15 22:49:27 +05:30 committed by GitHub
commit 6270e49ce7
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GPG Key ID: 4AEE18F83AFDEB23
15 changed files with 2966 additions and 3202 deletions

9
.gitignore vendored
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@ -34,14 +34,7 @@ __pycache__/
# Created by default with `src/ci/docker/run.sh`:
/obj/
/rustllvm/
/src/libcore/unicode/DerivedCoreProperties.txt
/src/libcore/unicode/DerivedNormalizationProps.txt
/src/libcore/unicode/PropList.txt
/src/libcore/unicode/ReadMe.txt
/src/libcore/unicode/Scripts.txt
/src/libcore/unicode/SpecialCasing.txt
/src/libcore/unicode/UnicodeData.txt
/src/libcore/unicode/downloaded
/unicode-downloads
/target/
# Generated by compiletest for incremental:
/tmp/

View File

@ -4953,6 +4953,16 @@ version = "1.10.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "612d636f949607bdf9b123b4a6f6d966dedf3ff669f7f045890d3a4a73948169"
[[package]]
name = "ucd-parse"
version = "0.1.4"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "ca6b52bf4da6512f0f07785a04769222e50d29639e7ecd016b7806fd2de306b4"
dependencies = [
"lazy_static 1.3.0",
"regex",
]
[[package]]
name = "ucd-trie"
version = "0.1.1"
@ -4974,6 +4984,13 @@ dependencies = [
"version_check 0.1.5",
]
[[package]]
name = "unicode-bdd"
version = "0.1.0"
dependencies = [
"ucd-parse",
]
[[package]]
name = "unicode-bidi"
version = "0.3.4"

View File

@ -23,6 +23,7 @@ members = [
"src/tools/rustfmt",
"src/tools/miri",
"src/tools/rustdoc-themes",
"src/tools/unicode-table-generator",
]
exclude = [
"build",

View File

@ -3,7 +3,7 @@
use crate::slice;
use crate::str::from_utf8_unchecked_mut;
use crate::unicode::printable::is_printable;
use crate::unicode::tables::{conversions, derived_property, general_category, property};
use crate::unicode::{self, conversions};
use super::*;
@ -552,7 +552,7 @@ impl char {
pub fn is_alphabetic(self) -> bool {
match self {
'a'..='z' | 'A'..='Z' => true,
c => c > '\x7f' && derived_property::Alphabetic(c),
c => c > '\x7f' && unicode::Alphabetic(c),
}
}
@ -583,7 +583,7 @@ impl char {
pub fn is_lowercase(self) -> bool {
match self {
'a'..='z' => true,
c => c > '\x7f' && derived_property::Lowercase(c),
c => c > '\x7f' && unicode::Lowercase(c),
}
}
@ -614,7 +614,7 @@ impl char {
pub fn is_uppercase(self) -> bool {
match self {
'A'..='Z' => true,
c => c > '\x7f' && derived_property::Uppercase(c),
c => c > '\x7f' && unicode::Uppercase(c),
}
}
@ -642,7 +642,7 @@ impl char {
pub fn is_whitespace(self) -> bool {
match self {
' ' | '\x09'..='\x0d' => true,
c => c > '\x7f' && property::White_Space(c),
c => c > '\x7f' && unicode::White_Space(c),
}
}
@ -693,7 +693,7 @@ impl char {
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn is_control(self) -> bool {
general_category::Cc(self)
unicode::Cc(self)
}
/// Returns `true` if this `char` has the `Grapheme_Extend` property.
@ -707,7 +707,7 @@ impl char {
/// [`DerivedCoreProperties.txt`]: https://www.unicode.org/Public/UCD/latest/ucd/DerivedCoreProperties.txt
#[inline]
pub(crate) fn is_grapheme_extended(self) -> bool {
derived_property::Grapheme_Extend(self)
unicode::Grapheme_Extend(self)
}
/// Returns `true` if this `char` has one of the general categories for numbers.
@ -739,7 +739,7 @@ impl char {
pub fn is_numeric(self) -> bool {
match self {
'0'..='9' => true,
c => c > '\x7f' && general_category::N(c),
c => c > '\x7f' && unicode::N(c),
}
}

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@ -37,9 +37,9 @@ pub use self::decode::{decode_utf16, DecodeUtf16, DecodeUtf16Error};
// unstable re-exports
#[unstable(feature = "unicode_version", issue = "49726")]
pub use crate::unicode::tables::UNICODE_VERSION;
#[unstable(feature = "unicode_version", issue = "49726")]
pub use crate::unicode::version::UnicodeVersion;
#[unstable(feature = "unicode_version", issue = "49726")]
pub use crate::unicode::UNICODE_VERSION;
use crate::fmt::{self, Write};
use crate::iter::FusedIterator;

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@ -1,66 +0,0 @@
/// BoolTrie is a trie for representing a set of Unicode codepoints. It is
/// implemented with postfix compression (sharing of identical child nodes),
/// which gives both compact size and fast lookup.
///
/// The space of Unicode codepoints is divided into 3 subareas, each
/// represented by a trie with different depth. In the first (0..0x800), there
/// is no trie structure at all; each u64 entry corresponds to a bitvector
/// effectively holding 64 bool values.
///
/// In the second (0x800..0x10000), each child of the root node represents a
/// 64-wide subrange, but instead of storing the full 64-bit value of the leaf,
/// the trie stores an 8-bit index into a shared table of leaf values. This
/// exploits the fact that in reasonable sets, many such leaves can be shared.
///
/// In the third (0x10000..0x110000), each child of the root node represents a
/// 4096-wide subrange, and the trie stores an 8-bit index into a 64-byte slice
/// of a child tree. Each of these 64 bytes represents an index into the table
/// of shared 64-bit leaf values. This exploits the sparse structure in the
/// non-BMP range of most Unicode sets.
pub struct BoolTrie {
// 0..0x800 (corresponding to 1 and 2 byte utf-8 sequences)
pub r1: [u64; 32], // leaves
// 0x800..0x10000 (corresponding to 3 byte utf-8 sequences)
pub r2: [u8; 992], // first level
pub r3: &'static [u64], // leaves
// 0x10000..0x110000 (corresponding to 4 byte utf-8 sequences)
pub r4: [u8; 256], // first level
pub r5: &'static [u8], // second level
pub r6: &'static [u64], // leaves
}
impl BoolTrie {
pub fn lookup(&self, c: char) -> bool {
let c = c as u32;
if c < 0x800 {
trie_range_leaf(c, self.r1[(c >> 6) as usize])
} else if c < 0x10000 {
let child = self.r2[(c >> 6) as usize - 0x20];
trie_range_leaf(c, self.r3[child as usize])
} else {
let child = self.r4[(c >> 12) as usize - 0x10];
let leaf = self.r5[((child as usize) << 6) + ((c >> 6) as usize & 0x3f)];
trie_range_leaf(c, self.r6[leaf as usize])
}
}
}
pub struct SmallBoolTrie {
pub(crate) r1: &'static [u8], // first level
pub(crate) r2: &'static [u64], // leaves
}
impl SmallBoolTrie {
pub fn lookup(&self, c: char) -> bool {
let c = c as u32;
match self.r1.get((c >> 6) as usize) {
Some(&child) => trie_range_leaf(c, self.r2[child as usize]),
None => false,
}
}
}
fn trie_range_leaf(c: u32, bitmap_chunk: u64) -> bool {
((bitmap_chunk >> (c & 63)) & 1) != 0
}

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@ -1,15 +1,59 @@
#![unstable(feature = "unicode_internals", issue = "none")]
#![allow(missing_docs)]
mod bool_trie;
pub(crate) mod printable;
pub(crate) mod tables;
mod unicode_data;
pub(crate) mod version;
use version::UnicodeVersion;
/// The version of [Unicode](http://www.unicode.org/) that the Unicode parts of
/// `char` and `str` methods are based on.
#[unstable(feature = "unicode_version", issue = "49726")]
pub const UNICODE_VERSION: UnicodeVersion = UnicodeVersion {
major: unicode_data::UNICODE_VERSION.0,
minor: unicode_data::UNICODE_VERSION.1,
micro: unicode_data::UNICODE_VERSION.2,
_priv: (),
};
// For use in liballoc, not re-exported in libstd.
pub mod derived_property {
pub use crate::unicode::tables::derived_property::{Case_Ignorable, Cased};
pub use super::{Case_Ignorable, Cased};
}
pub mod conversions {
pub use crate::unicode::tables::conversions::{to_lower, to_upper};
pub use unicode_data::alphabetic::lookup as Alphabetic;
pub use unicode_data::case_ignorable::lookup as Case_Ignorable;
pub use unicode_data::cased::lookup as Cased;
pub use unicode_data::cc::lookup as Cc;
pub use unicode_data::conversions;
pub use unicode_data::grapheme_extend::lookup as Grapheme_Extend;
pub use unicode_data::lowercase::lookup as Lowercase;
pub use unicode_data::n::lookup as N;
pub use unicode_data::uppercase::lookup as Uppercase;
pub use unicode_data::white_space::lookup as White_Space;
#[inline(always)]
fn range_search<const N: usize, const N1: usize, const N2: usize>(
needle: u32,
chunk_idx_map: &[u8; N],
(last_chunk_idx, last_chunk_mapping): (u16, u8),
bitset_chunk_idx: &[[u8; 16]; N1],
bitset: &[u64; N2],
) -> bool {
let bucket_idx = (needle / 64) as usize;
let chunk_map_idx = bucket_idx / 16;
let chunk_piece = bucket_idx % 16;
let chunk_idx = if chunk_map_idx >= N {
if chunk_map_idx == last_chunk_idx as usize {
last_chunk_mapping
} else {
return false;
}
} else {
chunk_idx_map[chunk_map_idx]
};
let idx = bitset_chunk_idx[(chunk_idx as usize)][chunk_piece];
let word = bitset[(idx as usize)];
(word & (1 << (needle % 64) as u64)) != 0
}

File diff suppressed because it is too large Load Diff

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@ -1,878 +0,0 @@
#!/usr/bin/env python
"""
Regenerate Unicode tables (tables.rs).
"""
# This script uses the Unicode tables as defined
# in the UnicodeFiles class.
# Since this should not require frequent updates, we just store this
# out-of-line and check the tables.rs file into git.
# Note that the "curl" program is required for operation.
# This script is compatible with Python 2.7 and 3.x.
import argparse
import datetime
import fileinput
import itertools
import os
import re
import textwrap
import subprocess
from collections import defaultdict, namedtuple
try:
# Python 3
from itertools import zip_longest
from io import StringIO
except ImportError:
# Python 2 compatibility
zip_longest = itertools.izip_longest
from StringIO import StringIO
try:
# Completely optional type hinting
# (Python 2 compatible using comments,
# see: https://mypy.readthedocs.io/en/latest/python2.html)
# This is very helpful in typing-aware IDE like PyCharm.
from typing import Any, Callable, Dict, Iterable, Iterator, List, Optional, Set, Tuple
except ImportError:
pass
# We don't use enum.Enum because of Python 2.7 compatibility.
class UnicodeFiles(object):
# ReadMe does not contain any Unicode data, we
# only use it to extract versions.
README = "ReadMe.txt"
DERIVED_CORE_PROPERTIES = "DerivedCoreProperties.txt"
DERIVED_NORMALIZATION_PROPS = "DerivedNormalizationProps.txt"
PROPS = "PropList.txt"
SCRIPTS = "Scripts.txt"
SPECIAL_CASING = "SpecialCasing.txt"
UNICODE_DATA = "UnicodeData.txt"
# The order doesn't really matter (Python < 3.6 won't preserve it),
# we only want to aggregate all the file names.
ALL_UNICODE_FILES = tuple(
value for name, value in UnicodeFiles.__dict__.items()
if not name.startswith("_")
)
assert len(ALL_UNICODE_FILES) == 7, "Unexpected number of unicode files"
# The directory this file is located in.
THIS_DIR = os.path.dirname(os.path.realpath(__file__))
# Where to download the Unicode data. The downloaded files
# will be placed in sub-directories named after Unicode version.
FETCH_DIR = os.path.join(THIS_DIR, "downloaded")
FETCH_URL_LATEST = "ftp://ftp.unicode.org/Public/UNIDATA/{filename}"
FETCH_URL_VERSION = "ftp://ftp.unicode.org/Public/{version}/ucd/{filename}"
PREAMBLE = """\
// NOTE: The following code was generated by "./unicode.py", do not edit directly
#![allow(missing_docs, non_upper_case_globals, non_snake_case, clippy::unreadable_literal)]
use crate::unicode::bool_trie::{{BoolTrie, SmallBoolTrie}};
use crate::unicode::version::UnicodeVersion;
""".format(year=datetime.datetime.now().year)
# Mapping taken from Table 12 from:
# http://www.unicode.org/reports/tr44/#General_Category_Values
EXPANDED_CATEGORIES = {
"Lu": ["LC", "L"], "Ll": ["LC", "L"], "Lt": ["LC", "L"],
"Lm": ["L"], "Lo": ["L"],
"Mn": ["M"], "Mc": ["M"], "Me": ["M"],
"Nd": ["N"], "Nl": ["N"], "No": ["N"],
"Pc": ["P"], "Pd": ["P"], "Ps": ["P"], "Pe": ["P"],
"Pi": ["P"], "Pf": ["P"], "Po": ["P"],
"Sm": ["S"], "Sc": ["S"], "Sk": ["S"], "So": ["S"],
"Zs": ["Z"], "Zl": ["Z"], "Zp": ["Z"],
"Cc": ["C"], "Cf": ["C"], "Cs": ["C"], "Co": ["C"], "Cn": ["C"],
}
# This is the (inclusive) range of surrogate codepoints.
# These are not valid Rust characters.
SURROGATE_CODEPOINTS_RANGE = (0xd800, 0xdfff)
UnicodeData = namedtuple(
"UnicodeData", (
# Conversions:
"to_upper", "to_lower", "to_title",
# Decompositions: canonical decompositions, compatibility decomp
"canon_decomp", "compat_decomp",
# Grouped: general categories and combining characters
"general_categories", "combines",
)
)
UnicodeVersion = namedtuple(
"UnicodeVersion", ("major", "minor", "micro", "as_str")
)
def fetch_files(version=None):
# type: (str) -> UnicodeVersion
"""
Fetch all the Unicode files from unicode.org.
This will use cached files (stored in `FETCH_DIR`) if they exist,
creating them if they don't. In any case, the Unicode version
is always returned.
:param version: The desired Unicode version, as string.
(If None, defaults to latest final release available,
querying the unicode.org service).
"""
have_version = check_stored_version(version)
if have_version:
return have_version
if version:
# Check if the desired version exists on the server.
get_fetch_url = lambda name: FETCH_URL_VERSION.format(version=version, filename=name)
else:
# Extract the latest version.
get_fetch_url = lambda name: FETCH_URL_LATEST.format(filename=name)
readme_url = get_fetch_url(UnicodeFiles.README)
print("Fetching: {}".format(readme_url))
readme_content = subprocess.check_output(("curl", readme_url))
unicode_version = parse_readme_unicode_version(
readme_content.decode("utf8")
)
download_dir = get_unicode_dir(unicode_version)
if not os.path.exists(download_dir):
# For 2.7 compat, we don't use `exist_ok=True`.
os.makedirs(download_dir)
for filename in ALL_UNICODE_FILES:
file_path = get_unicode_file_path(unicode_version, filename)
if os.path.exists(file_path):
# Assume file on the server didn't change if it's been saved before.
continue
if filename == UnicodeFiles.README:
with open(file_path, "wb") as fd:
fd.write(readme_content)
else:
url = get_fetch_url(filename)
print("Fetching: {}".format(url))
subprocess.check_call(("curl", "-o", file_path, url))
return unicode_version
def check_stored_version(version):
# type: (Optional[str]) -> Optional[UnicodeVersion]
"""
Given desired Unicode version, return the version
if stored files are all present, and `None` otherwise.
"""
if not version:
# If no desired version specified, we should check what's the latest
# version, skipping stored version checks.
return None
fetch_dir = os.path.join(FETCH_DIR, version)
for filename in ALL_UNICODE_FILES:
file_path = os.path.join(fetch_dir, filename)
if not os.path.exists(file_path):
return None
with open(os.path.join(fetch_dir, UnicodeFiles.README)) as fd:
return parse_readme_unicode_version(fd.read())
def parse_readme_unicode_version(readme_content):
# type: (str) -> UnicodeVersion
"""
Parse the Unicode version contained in their `ReadMe.txt` file.
"""
# "Raw string" is necessary for \d not being treated as escape char
# (for the sake of compat with future Python versions).
# See: https://docs.python.org/3.6/whatsnew/3.6.html#deprecated-python-behavior
pattern = r"for Version (\d+)\.(\d+)\.(\d+) of the Unicode"
groups = re.search(pattern, readme_content).groups()
return UnicodeVersion(*map(int, groups), as_str=".".join(groups))
def get_unicode_dir(unicode_version):
# type: (UnicodeVersion) -> str
"""
Indicate in which parent dir the Unicode data files should be stored.
This returns a full, absolute path.
"""
return os.path.join(FETCH_DIR, unicode_version.as_str)
def get_unicode_file_path(unicode_version, filename):
# type: (UnicodeVersion, str) -> str
"""
Indicate where the Unicode data file should be stored.
"""
return os.path.join(get_unicode_dir(unicode_version), filename)
def is_surrogate(n):
# type: (int) -> bool
"""
Tell if given codepoint is a surrogate (not a valid Rust character).
"""
return SURROGATE_CODEPOINTS_RANGE[0] <= n <= SURROGATE_CODEPOINTS_RANGE[1]
def load_unicode_data(file_path):
# type: (str) -> UnicodeData
"""
Load main Unicode data.
"""
# Conversions
to_lower = {} # type: Dict[int, Tuple[int, int, int]]
to_upper = {} # type: Dict[int, Tuple[int, int, int]]
to_title = {} # type: Dict[int, Tuple[int, int, int]]
# Decompositions
compat_decomp = {} # type: Dict[int, List[int]]
canon_decomp = {} # type: Dict[int, List[int]]
# Combining characters
# FIXME: combines are not used
combines = defaultdict(set) # type: Dict[str, Set[int]]
# Categories
general_categories = defaultdict(set) # type: Dict[str, Set[int]]
category_assigned_codepoints = set() # type: Set[int]
all_codepoints = {}
range_start = -1
for line in fileinput.input(file_path):
data = line.split(";")
if len(data) != 15:
continue
codepoint = int(data[0], 16)
if is_surrogate(codepoint):
continue
if range_start >= 0:
for i in range(range_start, codepoint):
all_codepoints[i] = data
range_start = -1
if data[1].endswith(", First>"):
range_start = codepoint
continue
all_codepoints[codepoint] = data
for code, data in all_codepoints.items():
(code_org, name, gencat, combine, bidi,
decomp, deci, digit, num, mirror,
old, iso, upcase, lowcase, titlecase) = data
# Generate char to char direct common and simple conversions:
# Uppercase to lowercase
if lowcase != "" and code_org != lowcase:
to_lower[code] = (int(lowcase, 16), 0, 0)
# Lowercase to uppercase
if upcase != "" and code_org != upcase:
to_upper[code] = (int(upcase, 16), 0, 0)
# Title case
if titlecase.strip() != "" and code_org != titlecase:
to_title[code] = (int(titlecase, 16), 0, 0)
# Store decomposition, if given
if decomp:
decompositions = decomp.split()[1:]
decomp_code_points = [int(i, 16) for i in decompositions]
if decomp.startswith("<"):
# Compatibility decomposition
compat_decomp[code] = decomp_code_points
else:
# Canonical decomposition
canon_decomp[code] = decomp_code_points
# Place letter in categories as appropriate.
for cat in itertools.chain((gencat, ), EXPANDED_CATEGORIES.get(gencat, [])):
general_categories[cat].add(code)
category_assigned_codepoints.add(code)
# Record combining class, if any.
if combine != "0":
combines[combine].add(code)
# Generate Not_Assigned from Assigned.
general_categories["Cn"] = get_unassigned_codepoints(category_assigned_codepoints)
# Other contains Not_Assigned
general_categories["C"].update(general_categories["Cn"])
grouped_categories = group_categories(general_categories)
# FIXME: combines are not used
return UnicodeData(
to_lower=to_lower, to_upper=to_upper, to_title=to_title,
compat_decomp=compat_decomp, canon_decomp=canon_decomp,
general_categories=grouped_categories, combines=combines,
)
def load_special_casing(file_path, unicode_data):
# type: (str, UnicodeData) -> None
"""
Load special casing data and enrich given Unicode data.
"""
for line in fileinput.input(file_path):
data = line.split("#")[0].split(";")
if len(data) == 5:
code, lower, title, upper, _comment = data
elif len(data) == 6:
code, lower, title, upper, condition, _comment = data
if condition.strip(): # Only keep unconditional mappins
continue
else:
continue
code = code.strip()
lower = lower.strip()
title = title.strip()
upper = upper.strip()
key = int(code, 16)
for (map_, values) in ((unicode_data.to_lower, lower),
(unicode_data.to_upper, upper),
(unicode_data.to_title, title)):
if values != code:
split = values.split()
codepoints = list(itertools.chain(
(int(i, 16) for i in split),
(0 for _ in range(len(split), 3))
))
assert len(codepoints) == 3
map_[key] = codepoints
def group_categories(mapping):
# type: (Dict[Any, Iterable[int]]) -> Dict[str, List[Tuple[int, int]]]
"""
Group codepoints mapped in "categories".
"""
return {category: group_codepoints(codepoints)
for category, codepoints in mapping.items()}
def group_codepoints(codepoints):
# type: (Iterable[int]) -> List[Tuple[int, int]]
"""
Group integral values into continuous, disjoint value ranges.
Performs value deduplication.
:return: sorted list of pairs denoting start and end of codepoint
group values, both ends inclusive.
>>> group_codepoints([1, 2, 10, 11, 12, 3, 4])
[(1, 4), (10, 12)]
>>> group_codepoints([1])
[(1, 1)]
>>> group_codepoints([1, 5, 6])
[(1, 1), (5, 6)]
>>> group_codepoints([])
[]
"""
sorted_codes = sorted(set(codepoints))
result = [] # type: List[Tuple[int, int]]
if not sorted_codes:
return result
next_codes = sorted_codes[1:]
start_code = sorted_codes[0]
for code, next_code in zip_longest(sorted_codes, next_codes, fillvalue=None):
if next_code is None or next_code - code != 1:
result.append((start_code, code))
start_code = next_code
return result
def ungroup_codepoints(codepoint_pairs):
# type: (Iterable[Tuple[int, int]]) -> List[int]
"""
The inverse of group_codepoints -- produce a flat list of values
from value range pairs.
>>> ungroup_codepoints([(1, 4), (10, 12)])
[1, 2, 3, 4, 10, 11, 12]
>>> ungroup_codepoints([(1, 1), (5, 6)])
[1, 5, 6]
>>> ungroup_codepoints(group_codepoints([1, 2, 7, 8]))
[1, 2, 7, 8]
>>> ungroup_codepoints([])
[]
"""
return list(itertools.chain.from_iterable(
range(lo, hi + 1) for lo, hi in codepoint_pairs
))
def get_unassigned_codepoints(assigned_codepoints):
# type: (Set[int]) -> Set[int]
"""
Given a set of "assigned" codepoints, return a set
of these that are not in assigned and not surrogate.
"""
return {i for i in range(0, 0x110000)
if i not in assigned_codepoints and not is_surrogate(i)}
def generate_table_lines(items, indent, wrap=98):
# type: (Iterable[str], int, int) -> Iterator[str]
"""
Given table items, generate wrapped lines of text with comma-separated items.
This is a generator function.
:param wrap: soft wrap limit (characters per line), integer.
"""
line = " " * indent
first = True
for item in items:
if len(line) + len(item) < wrap:
if first:
line += item
else:
line += ", " + item
first = False
else:
yield line + ",\n"
line = " " * indent + item
yield line
def load_properties(file_path, interesting_props):
# type: (str, Iterable[str]) -> Dict[str, List[Tuple[int, int]]]
"""
Load properties data and return in grouped form.
"""
props = defaultdict(list) # type: Dict[str, List[Tuple[int, int]]]
# "Raw string" is necessary for `\.` and `\w` not to be treated as escape chars
# (for the sake of compat with future Python versions).
# See: https://docs.python.org/3.6/whatsnew/3.6.html#deprecated-python-behavior
re1 = re.compile(r"^ *([0-9A-F]+) *; *(\w+)")
re2 = re.compile(r"^ *([0-9A-F]+)\.\.([0-9A-F]+) *; *(\w+)")
for line in fileinput.input(file_path):
match = re1.match(line) or re2.match(line)
if match:
groups = match.groups()
if len(groups) == 2:
# `re1` matched (2 groups).
d_lo, prop = groups
d_hi = d_lo
else:
d_lo, d_hi, prop = groups
else:
continue
if interesting_props and prop not in interesting_props:
continue
lo_value = int(d_lo, 16)
hi_value = int(d_hi, 16)
props[prop].append((lo_value, hi_value))
# Optimize if possible.
for prop in props:
props[prop] = group_codepoints(ungroup_codepoints(props[prop]))
return props
def escape_char(c):
# type: (int) -> str
r"""
Escape a codepoint for use as Rust char literal.
Outputs are OK to use as Rust source code as char literals
and they also include necessary quotes.
>>> escape_char(97)
"'\\u{61}'"
>>> escape_char(0)
"'\\0'"
"""
return r"'\u{%x}'" % c if c != 0 else r"'\0'"
def format_char_pair(pair):
# type: (Tuple[int, int]) -> str
"""
Format a pair of two Rust chars.
"""
return "(%s,%s)" % (escape_char(pair[0]), escape_char(pair[1]))
def generate_table(
name, # type: str
items, # type: List[Tuple[int, int]]
decl_type="&[(char, char)]", # type: str
is_pub=True, # type: bool
format_item=format_char_pair, # type: Callable[[Tuple[int, int]], str]
):
# type: (...) -> Iterator[str]
"""
Generate a nicely formatted Rust constant "table" array.
This generates actual Rust code.
"""
pub_string = ""
if is_pub:
pub_string = "pub "
yield "\n"
yield " #[rustfmt::skip]\n"
yield " %sconst %s: %s = &[\n" % (pub_string, name, decl_type)
data = []
first = True
for item in items:
if not first:
data.append(",")
first = False
data.extend(format_item(item))
for table_line in generate_table_lines("".join(data).split(","), 8):
yield table_line
yield "\n ];\n"
def compute_trie(raw_data, chunk_size):
# type: (List[int], int) -> Tuple[List[int], List[int]]
"""
Compute postfix-compressed trie.
See: bool_trie.rs for more details.
>>> compute_trie([1, 2, 3, 1, 2, 3, 4, 5, 6], 3)
([0, 0, 1], [1, 2, 3, 4, 5, 6])
>>> compute_trie([1, 2, 3, 1, 2, 4, 4, 5, 6], 3)
([0, 1, 2], [1, 2, 3, 1, 2, 4, 4, 5, 6])
"""
root = []
childmap = {} # type: Dict[Tuple[int, ...], int]
child_data = []
assert len(raw_data) % chunk_size == 0, "Chunks must be equally sized"
for i in range(len(raw_data) // chunk_size):
data = raw_data[i * chunk_size : (i + 1) * chunk_size]
# Postfix compression of child nodes (data chunks)
# (identical child nodes are shared).
# Make a tuple out of the list so it's hashable.
child = tuple(data)
if child not in childmap:
childmap[child] = len(childmap)
child_data.extend(data)
root.append(childmap[child])
return root, child_data
def generate_bool_trie(name, codepoint_ranges, is_pub=False):
# type: (str, List[Tuple[int, int]], bool) -> Iterator[str]
"""
Generate Rust code for BoolTrie struct.
This yields string fragments that should be joined to produce
the final string.
See: `bool_trie.rs`.
"""
chunk_size = 64
rawdata = [False] * 0x110000
for (lo, hi) in codepoint_ranges:
for cp in range(lo, hi + 1):
rawdata[cp] = True
# Convert to bitmap chunks of `chunk_size` bits each.
chunks = []
for i in range(0x110000 // chunk_size):
chunk = 0
for j in range(chunk_size):
if rawdata[i * chunk_size + j]:
chunk |= 1 << j
chunks.append(chunk)
pub_string = ""
if is_pub:
pub_string = "pub "
yield "\n"
yield " #[rustfmt::skip]\n"
yield " %sconst %s: &super::BoolTrie = &super::BoolTrie {\n" % (pub_string, name)
yield " r1: [\n"
data = ("0x%016x" % chunk for chunk in chunks[:0x800 // chunk_size])
for fragment in generate_table_lines(data, 12):
yield fragment
yield "\n ],\n"
# 0x800..0x10000 trie
(r2, r3) = compute_trie(chunks[0x800 // chunk_size : 0x10000 // chunk_size], 64 // chunk_size)
yield " r2: [\n"
data = map(str, r2)
for fragment in generate_table_lines(data, 12):
yield fragment
yield "\n ],\n"
yield " r3: &[\n"
data = ("0x%016x" % node for node in r3)
for fragment in generate_table_lines(data, 12):
yield fragment
yield "\n ],\n"
# 0x10000..0x110000 trie
(mid, r6) = compute_trie(chunks[0x10000 // chunk_size : 0x110000 // chunk_size],
64 // chunk_size)
(r4, r5) = compute_trie(mid, 64)
yield " r4: [\n"
data = map(str, r4)
for fragment in generate_table_lines(data, 12):
yield fragment
yield "\n ],\n"
yield " r5: &[\n"
data = map(str, r5)
for fragment in generate_table_lines(data, 12):
yield fragment
yield "\n ],\n"
yield " r6: &[\n"
data = ("0x%016x" % node for node in r6)
for fragment in generate_table_lines(data, 12):
yield fragment
yield "\n ],\n"
yield " };\n"
def generate_small_bool_trie(name, codepoint_ranges, is_pub=False):
# type: (str, List[Tuple[int, int]], bool) -> Iterator[str]
"""
Generate Rust code for `SmallBoolTrie` struct.
See: `bool_trie.rs`.
"""
last_chunk = max(hi // 64 for (lo, hi) in codepoint_ranges)
n_chunks = last_chunk + 1
chunks = [0] * n_chunks
for (lo, hi) in codepoint_ranges:
for cp in range(lo, hi + 1):
assert cp // 64 < len(chunks)
chunks[cp // 64] |= 1 << (cp & 63)
pub_string = ""
if is_pub:
pub_string = "pub "
yield "\n"
yield " #[rustfmt::skip]\n"
yield (" %sconst %s: &super::SmallBoolTrie = &super::SmallBoolTrie {\n"
% (pub_string, name))
(r1, r2) = compute_trie(chunks, 1)
yield " r1: &[\n"
data = (str(node) for node in r1)
for fragment in generate_table_lines(data, 12):
yield fragment
yield "\n ],\n"
yield " r2: &[\n"
data = ("0x%016x" % node for node in r2)
for fragment in generate_table_lines(data, 12):
yield fragment
yield "\n ],\n"
yield " };\n"
def generate_property_module(mod, grouped_categories, category_subset):
# type: (str, Dict[str, List[Tuple[int, int]]], Iterable[str]) -> Iterator[str]
"""
Generate Rust code for module defining properties.
"""
yield "pub(crate) mod %s {" % mod
for cat in sorted(category_subset):
if cat in ("Cc", "White_Space"):
generator = generate_small_bool_trie("%s_table" % cat, grouped_categories[cat])
else:
generator = generate_bool_trie("%s_table" % cat, grouped_categories[cat])
for fragment in generator:
yield fragment
yield "\n"
yield " pub fn %s(c: char) -> bool {\n" % cat
yield " %s_table.lookup(c)\n" % cat
yield " }\n"
yield "}\n\n"
def generate_conversions_module(unicode_data):
# type: (UnicodeData) -> Iterator[str]
"""
Generate Rust code for module defining conversions.
"""
yield "pub(crate) mod conversions {"
yield """
pub fn to_lower(c: char) -> [char; 3] {
match bsearch_case_table(c, to_lowercase_table) {
None => [c, '\\0', '\\0'],
Some(index) => to_lowercase_table[index].1,
}
}
pub fn to_upper(c: char) -> [char; 3] {
match bsearch_case_table(c, to_uppercase_table) {
None => [c, '\\0', '\\0'],
Some(index) => to_uppercase_table[index].1,
}
}
fn bsearch_case_table(c: char, table: &[(char, [char; 3])]) -> Option<usize> {
table.binary_search_by(|&(key, _)| key.cmp(&c)).ok()
}\n"""
decl_type = "&[(char, [char; 3])]"
format_conversion = lambda x: "({},[{},{},{}])".format(*(
escape_char(c) for c in (x[0], x[1][0], x[1][1], x[1][2])
))
for fragment in generate_table(
name="to_lowercase_table",
items=sorted(unicode_data.to_lower.items(), key=lambda x: x[0]),
decl_type=decl_type,
is_pub=False,
format_item=format_conversion
):
yield fragment
for fragment in generate_table(
name="to_uppercase_table",
items=sorted(unicode_data.to_upper.items(), key=lambda x: x[0]),
decl_type=decl_type,
is_pub=False,
format_item=format_conversion
):
yield fragment
yield "}\n"
def parse_args():
# type: () -> argparse.Namespace
"""
Parse command line arguments.
"""
parser = argparse.ArgumentParser(description=__doc__)
parser.add_argument("-v", "--version", default=None, type=str,
help="Unicode version to use (if not specified,"
" defaults to latest release).")
return parser.parse_args()
def main():
# type: () -> None
"""
Script entry point.
"""
args = parse_args()
unicode_version = fetch_files(args.version)
print("Using Unicode version: {}".format(unicode_version.as_str))
# All the writing happens entirely in memory, we only write to file
# once we have generated the file content (it's not very large, <1 MB).
buf = StringIO()
buf.write(PREAMBLE)
unicode_version_notice = textwrap.dedent("""
/// The version of [Unicode](http://www.unicode.org/) that the Unicode parts of
/// `char` and `str` methods are based on.
#[unstable(feature = "unicode_version", issue = "49726")]
pub const UNICODE_VERSION: UnicodeVersion =
UnicodeVersion {{ major: {v.major}, minor: {v.minor}, micro: {v.micro}, _priv: () }};
""").format(v=unicode_version)
buf.write(unicode_version_notice)
get_path = lambda f: get_unicode_file_path(unicode_version, f)
unicode_data = load_unicode_data(get_path(UnicodeFiles.UNICODE_DATA))
load_special_casing(get_path(UnicodeFiles.SPECIAL_CASING), unicode_data)
want_derived = {"Alphabetic", "Lowercase", "Uppercase",
"Cased", "Case_Ignorable", "Grapheme_Extend"}
derived = load_properties(get_path(UnicodeFiles.DERIVED_CORE_PROPERTIES), want_derived)
props = load_properties(get_path(UnicodeFiles.PROPS),
{"White_Space", "Join_Control", "Noncharacter_Code_Point"})
# Category tables
for (name, categories, category_subset) in (
("general_category", unicode_data.general_categories, ["N", "Cc"]),
("derived_property", derived, want_derived),
("property", props, ["White_Space"])
):
for fragment in generate_property_module(name, categories, category_subset):
buf.write(fragment)
for fragment in generate_conversions_module(unicode_data):
buf.write(fragment)
tables_rs_path = os.path.join(THIS_DIR, "tables.rs")
# Actually write out the file content.
# Will overwrite the file if it exists.
with open(tables_rs_path, "w") as fd:
fd.write(buf.getvalue())
print("Regenerated tables.rs.")
if __name__ == "__main__":
main()

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@ -0,0 +1,10 @@
[package]
name = "unicode-bdd"
version = "0.1.0"
authors = ["Mark Rousskov <mark.simulacrum@gmail.com>"]
edition = "2018"
# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
[dependencies]
ucd-parse = "0.1.3"

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@ -0,0 +1,62 @@
use crate::{fmt_list, UnicodeData};
use std::fmt;
pub(crate) fn generate_case_mapping(data: &UnicodeData) -> String {
let mut file = String::new();
file.push_str(HEADER.trim_start());
let decl_type = "&[(char, [char; 3])]";
file.push_str(&format!(
"static LOWERCASE_TABLE: {} = &[{}];",
decl_type,
fmt_list(data.to_lower.iter().map(to_mapping))
));
file.push_str("\n\n");
file.push_str(&format!(
"static UPPERCASE_TABLE: {} = &[{}];",
decl_type,
fmt_list(data.to_upper.iter().map(to_mapping))
));
file
}
fn to_mapping((key, (a, b, c)): (&u32, &(u32, u32, u32))) -> (CharEscape, [CharEscape; 3]) {
(
CharEscape(std::char::from_u32(*key).unwrap()),
[
CharEscape(std::char::from_u32(*a).unwrap()),
CharEscape(std::char::from_u32(*b).unwrap()),
CharEscape(std::char::from_u32(*c).unwrap()),
],
)
}
struct CharEscape(char);
impl fmt::Debug for CharEscape {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "'{}'", self.0.escape_default())
}
}
static HEADER: &str = "
pub fn to_lower(c: char) -> [char; 3] {
match bsearch_case_table(c, LOWERCASE_TABLE) {
None => [c, '\\0', '\\0'],
Some(index) => LOWERCASE_TABLE[index].1,
}
}
pub fn to_upper(c: char) -> [char; 3] {
match bsearch_case_table(c, UPPERCASE_TABLE) {
None => [c, '\\0', '\\0'],
Some(index) => UPPERCASE_TABLE[index].1,
}
}
fn bsearch_case_table(c: char, table: &[(char, [char; 3])]) -> Option<usize> {
table.binary_search_by(|&(key, _)| key.cmp(&c)).ok()
}
";

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@ -0,0 +1,261 @@
use std::collections::{BTreeMap, HashMap};
use std::ops::Range;
use ucd_parse::Codepoints;
mod case_mapping;
mod raw_emitter;
mod unicode_download;
use raw_emitter::{emit_codepoints, RawEmitter};
static PROPERTIES: &[&str] = &[
"Alphabetic",
"Lowercase",
"Uppercase",
"Cased",
"Case_Ignorable",
"Grapheme_Extend",
"White_Space",
"Cc",
"N",
];
struct UnicodeData {
ranges: Vec<(&'static str, Vec<Range<u32>>)>,
to_upper: BTreeMap<u32, (u32, u32, u32)>,
to_lower: BTreeMap<u32, (u32, u32, u32)>,
}
fn to_mapping(origin: u32, codepoints: Vec<ucd_parse::Codepoint>) -> Option<(u32, u32, u32)> {
let mut a = None;
let mut b = None;
let mut c = None;
for codepoint in codepoints {
if origin == codepoint.value() {
return None;
}
if a.is_none() {
a = Some(codepoint.value());
} else if b.is_none() {
b = Some(codepoint.value());
} else if c.is_none() {
c = Some(codepoint.value());
} else {
panic!("more than 3 mapped codepoints")
}
}
Some((a.unwrap(), b.unwrap_or(0), c.unwrap_or(0)))
}
static UNICODE_DIRECTORY: &str = "unicode-downloads";
fn load_data() -> UnicodeData {
unicode_download::fetch_latest();
let mut properties = HashMap::new();
for row in ucd_parse::parse::<_, ucd_parse::CoreProperty>(&UNICODE_DIRECTORY).unwrap() {
if let Some(name) = PROPERTIES.iter().find(|prop| **prop == row.property.as_str()) {
properties.entry(*name).or_insert_with(Vec::new).push(row.codepoints);
}
}
for row in ucd_parse::parse::<_, ucd_parse::Property>(&UNICODE_DIRECTORY).unwrap() {
if let Some(name) = PROPERTIES.iter().find(|prop| **prop == row.property.as_str()) {
properties.entry(*name).or_insert_with(Vec::new).push(row.codepoints);
}
}
let mut to_lower = BTreeMap::new();
let mut to_upper = BTreeMap::new();
for row in ucd_parse::UnicodeDataExpander::new(
ucd_parse::parse::<_, ucd_parse::UnicodeData>(&UNICODE_DIRECTORY).unwrap(),
) {
let general_category = if ["Nd", "Nl", "No"].contains(&row.general_category.as_str()) {
"N"
} else {
row.general_category.as_str()
};
if let Some(name) = PROPERTIES.iter().find(|prop| **prop == general_category) {
properties
.entry(*name)
.or_insert_with(Vec::new)
.push(Codepoints::Single(row.codepoint));
}
if let Some(mapped) = row.simple_lowercase_mapping {
if mapped != row.codepoint {
to_lower.insert(row.codepoint.value(), (mapped.value(), 0, 0));
}
}
if let Some(mapped) = row.simple_uppercase_mapping {
if mapped != row.codepoint {
to_upper.insert(row.codepoint.value(), (mapped.value(), 0, 0));
}
}
}
for row in ucd_parse::parse::<_, ucd_parse::SpecialCaseMapping>(&UNICODE_DIRECTORY).unwrap() {
if !row.conditions.is_empty() {
// Skip conditional case mappings
continue;
}
let key = row.codepoint.value();
if let Some(lower) = to_mapping(key, row.lowercase) {
to_lower.insert(key, lower);
}
if let Some(upper) = to_mapping(key, row.uppercase) {
to_upper.insert(key, upper);
}
}
let mut properties: HashMap<&'static str, Vec<Range<u32>>> = properties
.into_iter()
.map(|(k, v)| {
(
k,
v.into_iter()
.flat_map(|codepoints| match codepoints {
Codepoints::Single(c) => c
.scalar()
.map(|ch| (ch as u32..ch as u32 + 1))
.into_iter()
.collect::<Vec<_>>(),
Codepoints::Range(c) => c
.into_iter()
.flat_map(|c| c.scalar().map(|ch| (ch as u32..ch as u32 + 1)))
.collect::<Vec<_>>(),
})
.collect::<Vec<Range<u32>>>(),
)
})
.collect();
for ranges in properties.values_mut() {
merge_ranges(ranges);
}
let mut properties = properties.into_iter().collect::<Vec<_>>();
properties.sort_by_key(|p| p.0);
UnicodeData { ranges: properties, to_lower, to_upper }
}
fn main() {
let write_location = std::env::args().nth(1).unwrap_or_else(|| {
eprintln!("Must provide path to write unicode tables to");
eprintln!(
"e.g. {} src/libcore/unicode/unicode_data.rs",
std::env::args().nth(0).unwrap_or_default()
);
std::process::exit(1);
});
let unicode_data = load_data();
let ranges_by_property = &unicode_data.ranges;
let mut total_bytes = 0;
let mut modules = Vec::new();
for (property, ranges) in ranges_by_property {
let datapoints = ranges.iter().map(|r| r.end - r.start).sum::<u32>();
let mut emitter = RawEmitter::new();
emit_codepoints(&mut emitter, &ranges);
modules.push((property.to_lowercase().to_string(), emitter.file));
println!("{:15}: {} bytes, {} codepoints", property, emitter.bytes_used, datapoints,);
total_bytes += emitter.bytes_used;
}
let mut table_file = String::new();
table_file.push_str(
"///! This file is generated by src/tools/unicode-table-generator; do not edit manually!\n",
);
table_file.push_str("use super::range_search;\n\n");
table_file.push_str(&version());
table_file.push('\n');
modules.push((String::from("conversions"), case_mapping::generate_case_mapping(&unicode_data)));
for (name, contents) in modules {
table_file.push_str("#[rustfmt::skip]\n");
table_file.push_str(&format!("pub mod {} {{\n", name));
for line in contents.lines() {
if !line.trim().is_empty() {
table_file.push_str(" ");
table_file.push_str(&line);
}
table_file.push('\n');
}
table_file.push_str("}\n\n");
}
std::fs::write(&write_location, format!("{}\n", table_file.trim_end())).unwrap();
println!("Total table sizes: {} bytes", total_bytes);
}
fn version() -> String {
let mut out = String::new();
out.push_str("pub const UNICODE_VERSION: (u32, u32, u32) = ");
let readme =
std::fs::read_to_string(std::path::Path::new(UNICODE_DIRECTORY).join("ReadMe.txt"))
.unwrap();
let prefix = "for Version ";
let start = readme.find(prefix).unwrap() + prefix.len();
let end = readme.find(" of the Unicode Standard.").unwrap();
let version =
readme[start..end].split('.').map(|v| v.parse::<u32>().expect(&v)).collect::<Vec<_>>();
let [major, minor, micro] = [version[0], version[1], version[2]];
out.push_str(&format!("({}, {}, {});\n", major, minor, micro));
out
}
fn fmt_list<V: std::fmt::Debug>(values: impl IntoIterator<Item = V>) -> String {
let pieces = values.into_iter().map(|b| format!("{:?}, ", b)).collect::<Vec<_>>();
let mut out = String::new();
let mut line = format!("\n ");
for piece in pieces {
if line.len() + piece.len() < 98 {
line.push_str(&piece);
} else {
out.push_str(line.trim_end());
out.push('\n');
line = format!(" {}", piece);
}
}
out.push_str(line.trim_end());
out.push('\n');
out
}
fn merge_ranges(ranges: &mut Vec<Range<u32>>) {
loop {
let mut new_ranges = Vec::new();
let mut idx_iter = 0..(ranges.len() - 1);
while let Some(idx) = idx_iter.next() {
let cur = ranges[idx].clone();
let next = ranges[idx + 1].clone();
if cur.end == next.start {
let _ = idx_iter.next(); // skip next as we're merging it in
new_ranges.push(cur.start..next.end);
} else {
new_ranges.push(cur);
}
}
new_ranges.push(ranges.last().unwrap().clone());
if new_ranges.len() == ranges.len() {
*ranges = new_ranges;
break;
} else {
*ranges = new_ranges;
}
}
}

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//! This implements the core logic of the compression scheme used to compactly
//! encode the Unicode character classes.
//!
//! The primary idea is that we 'flatten' the Unicode ranges into an enormous
//! bitset. To represent any arbitrary codepoint in a raw bitset, we would need
//! over 17 kilobytes of data per character set -- way too much for our
//! purposes.
//!
//! We have two primary goals with the encoding: we want to be compact, because
//! these tables often end up in ~every Rust program (especially the
//! grapheme_extend table, used for str debugging), including those for embedded
//! targets (where space is important). We also want to be relatively fast,
//! though this is more of a nice to have rather than a key design constraint.
//! In practice, due to modern processor design these two are closely related.
//!
//! The encoding scheme here compresses the bitset by first deduplicating the
//! "words" (64 bits on all platforms). In practice very few words are present
//! in most data sets.
//!
//! This gives us an array that maps `u8 -> word` (if we ever went beyond 256
//! words, we could go to u16 -> word or have some dual compression scheme
//! mapping into two separate sets; currently this is not dealt with).
//!
//! With that scheme, we now have a single byte for every 64 codepoints. We
//! further group these by 16 (arbitrarily chosen), and again deduplicate and
//! store in an array (u8 -> [u8; 16]).
//!
//! The indices into this array represent ranges of 64*16 = 1024 codepoints.
//!
//! This already reduces the top-level array to at most 1,086 bytes, but in
//! practice we usually can encode in far fewer (the first couple Unicode planes
//! are dense).
//!
//! The last byte of this top-level array is pulled out to a separate static
//! and trailing zeros are dropped; this is simply because grapheme_extend and
//! case_ignorable have a single entry in the 896th entry, so this shrinks them
//! down considerably.
use crate::fmt_list;
use std::collections::{BTreeSet, HashMap};
use std::convert::TryFrom;
use std::fmt::Write;
use std::ops::Range;
pub struct RawEmitter {
pub file: String,
pub bytes_used: usize,
}
impl RawEmitter {
pub fn new() -> RawEmitter {
RawEmitter { file: String::new(), bytes_used: 0 }
}
fn blank_line(&mut self) {
if self.file.is_empty() || self.file.ends_with("\n\n") {
return;
}
writeln!(&mut self.file, "").unwrap();
}
fn emit_bitset(&mut self, words: &[u64]) {
let unique_words =
words.iter().cloned().collect::<BTreeSet<_>>().into_iter().collect::<Vec<_>>();
if unique_words.len() > u8::max_value() as usize {
panic!("cannot pack {} into 8 bits", unique_words.len());
}
let word_indices = unique_words
.iter()
.cloned()
.enumerate()
.map(|(idx, word)| (word, u8::try_from(idx).unwrap()))
.collect::<HashMap<_, _>>();
let mut idx = words.iter().map(|w| word_indices[w]).collect::<Vec<u8>>();
let chunk_length = 16;
for _ in 0..(chunk_length - (idx.len() % chunk_length)) {
assert_eq!(unique_words[0], 0, "first word is all zeros");
// pad out bitset index with zero words so we have all chunks of 16
idx.push(0);
}
let mut chunks = BTreeSet::new();
for chunk in idx.chunks(chunk_length) {
chunks.insert(chunk);
}
let chunk_map = chunks
.clone()
.into_iter()
.enumerate()
.map(|(idx, chunk)| (chunk, idx))
.collect::<HashMap<_, _>>();
let mut chunk_indices = Vec::new();
for chunk in idx.chunks(chunk_length) {
chunk_indices.push(chunk_map[chunk]);
}
writeln!(
&mut self.file,
"static BITSET_LAST_CHUNK_MAP: (u16, u8) = ({}, {});",
chunk_indices.len() - 1,
chunk_indices.pop().unwrap(),
)
.unwrap();
self.bytes_used += 3;
// Strip out the empty pieces, presuming our above pop() made us now
// have some trailing zeros.
assert_eq!(unique_words[0], 0, "first word is all zeros");
while let Some(0) = chunk_indices.last() {
chunk_indices.pop();
}
writeln!(
&mut self.file,
"static BITSET_CHUNKS_MAP: [u8; {}] = [{}];",
chunk_indices.len(),
fmt_list(&chunk_indices),
)
.unwrap();
self.bytes_used += chunk_indices.len();
writeln!(
&mut self.file,
"static BITSET_INDEX_CHUNKS: [[u8; 16]; {}] = [{}];",
chunks.len(),
fmt_list(chunks.iter()),
)
.unwrap();
self.bytes_used += 16 * chunks.len();
writeln!(
&mut self.file,
"static BITSET: [u64; {}] = [{}];",
unique_words.len(),
fmt_list(&unique_words),
)
.unwrap();
self.bytes_used += 8 * unique_words.len();
}
pub fn emit_lookup(&mut self) {
writeln!(&mut self.file, "pub fn lookup(c: char) -> bool {{").unwrap();
writeln!(&mut self.file, " super::range_search(",).unwrap();
writeln!(&mut self.file, " c as u32,").unwrap();
writeln!(&mut self.file, " &BITSET_CHUNKS_MAP,").unwrap();
writeln!(&mut self.file, " BITSET_LAST_CHUNK_MAP,").unwrap();
writeln!(&mut self.file, " &BITSET_INDEX_CHUNKS,").unwrap();
writeln!(&mut self.file, " &BITSET,").unwrap();
writeln!(&mut self.file, " )").unwrap();
writeln!(&mut self.file, "}}").unwrap();
}
}
pub fn emit_codepoints(emitter: &mut RawEmitter, ranges: &[Range<u32>]) {
emitter.blank_line();
let last_code_point = ranges.last().unwrap().end;
// bitset for every bit in the codepoint range
//
// + 2 to ensure an all zero word to use for padding
let mut buckets = vec![0u64; (last_code_point as usize / 64) + 2];
for range in ranges {
for codepoint in range.clone() {
let bucket = codepoint as usize / 64;
let bit = codepoint as u64 % 64;
buckets[bucket] |= 1 << bit;
}
}
emitter.emit_bitset(&buckets);
emitter.blank_line();
emitter.emit_lookup();
}

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use crate::UNICODE_DIRECTORY;
use std::path::Path;
use std::process::Command;
static URL_PREFIX: &str = "https://www.unicode.org/Public/UCD/latest/ucd/";
static README: &str = "ReadMe.txt";
static RESOURCES: &[&str] =
&["DerivedCoreProperties.txt", "PropList.txt", "UnicodeData.txt", "SpecialCasing.txt"];
pub fn fetch_latest() {
let directory = Path::new(UNICODE_DIRECTORY);
if let Err(e) = std::fs::create_dir_all(directory) {
if e.kind() != std::io::ErrorKind::AlreadyExists {
panic!("Failed to create {:?}: {}", UNICODE_DIRECTORY, e);
}
}
let output = Command::new("curl").arg(URL_PREFIX.to_owned() + README).output().unwrap();
if !output.status.success() {
panic!(
"Failed to run curl to fetch readme: stderr: {}",
String::from_utf8_lossy(&output.stderr)
);
}
let current = std::fs::read_to_string(directory.join(README)).unwrap_or_default();
if current.as_bytes() != &output.stdout[..] {
std::fs::write(directory.join(README), output.stdout).unwrap();
}
for resource in RESOURCES {
let output = Command::new("curl").arg(URL_PREFIX.to_owned() + resource).output().unwrap();
if !output.status.success() {
panic!(
"Failed to run curl to fetch {}: stderr: {}",
resource,
String::from_utf8_lossy(&output.stderr)
);
}
std::fs::write(directory.join(resource), output.stdout).unwrap();
}
}