f2c5f19557 Introduce the `small-hash` feature for `bitcoin_hashes` (Alekos Filini)
Pull request description:
When enabled this feature swaps the hash implementation of sha512, sha256 and ripemd160 for a smaller (but also slower) one.
On embedded processors (Cortex-M4) it can lead to up to a 52% size reduction, from around 37KiB for just the `process_block` methods of the three hash functions to 17.8KiB.
The following numbers were collected on `aarch64-unknown-linux-gnu` with `cargo 1.72.0-nightly`.
## Original
```
RUSTFLAGS='--cfg=bench -C opt-level=z' cargo bench
```
```
test hash160::benches::hash160_10 ... bench: 33 ns/iter (+/- 1) = 303 MB/s
test hash160::benches::hash160_1k ... bench: 2,953 ns/iter (+/- 187) = 346 MB/s
test hash160::benches::hash160_64k ... bench: 188,480 ns/iter (+/- 11,595) = 347 MB/s
test hmac::benches::hmac_sha256_10 ... bench: 33 ns/iter (+/- 2) = 303 MB/s
test hmac::benches::hmac_sha256_1k ... bench: 2,957 ns/iter (+/- 104) = 346 MB/s
test hmac::benches::hmac_sha256_64k ... bench: 192,022 ns/iter (+/- 6,407) = 341 MB/s
test ripemd160::benches::ripemd160_10 ... bench: 25 ns/iter (+/- 1) = 400 MB/s
test ripemd160::benches::ripemd160_1k ... bench: 2,288 ns/iter (+/- 93) = 447 MB/s
test ripemd160::benches::ripemd160_64k ... bench: 146,823 ns/iter (+/- 1,102) = 446 MB/s
test sha1::benches::sha1_10 ... bench: 41 ns/iter (+/- 0) = 243 MB/s
test sha1::benches::sha1_1k ... bench: 3,844 ns/iter (+/- 70) = 266 MB/s
test sha1::benches::sha1_64k ... bench: 245,854 ns/iter (+/- 10,158) = 266 MB/s
test sha256::benches::sha256_10 ... bench: 35 ns/iter (+/- 0) = 285 MB/s
test sha256::benches::sha256_1k ... bench: 3,063 ns/iter (+/- 15) = 334 MB/s
test sha256::benches::sha256_64k ... bench: 195,729 ns/iter (+/- 2,880) = 334 MB/s
test sha256d::benches::sha256d_10 ... bench: 34 ns/iter (+/- 1) = 294 MB/s
test sha256d::benches::sha256d_1k ... bench: 3,071 ns/iter (+/- 107) = 333 MB/s
test sha256d::benches::sha256d_64k ... bench: 188,614 ns/iter (+/- 8,101) = 347 MB/s
test sha512::benches::sha512_10 ... bench: 21 ns/iter (+/- 0) = 476 MB/s
test sha512::benches::sha512_1k ... bench: 1,714 ns/iter (+/- 36) = 597 MB/s
test sha512::benches::sha512_64k ... bench: 110,084 ns/iter (+/- 3,637) = 595 MB/s
test sha512_256::benches::sha512_256_10 ... bench: 22 ns/iter (+/- 1) = 454 MB/s
test sha512_256::benches::sha512_256_1k ... bench: 1,822 ns/iter (+/- 70) = 562 MB/s
test sha512_256::benches::sha512_256_64k ... bench: 116,231 ns/iter (+/- 4,745) = 563 MB/s
test siphash24::benches::siphash24_1ki ... bench: 1,072 ns/iter (+/- 41) = 955 MB/s
test siphash24::benches::siphash24_1ki_hash ... bench: 1,102 ns/iter (+/- 42) = 929 MB/s
test siphash24::benches::siphash24_1ki_hash_u64 ... bench: 1,064 ns/iter (+/- 41) = 962 MB/s
test siphash24::benches::siphash24_64ki ... bench: 69,957 ns/iter (+/- 2,712) = 936 MB/
```
```
0000000000005872 t _ZN84_$LT$bitcoin_hashes..ripemd160..HashEngine$u20$as$u20$bitcoin_hashes..HashEngine$GT$5input17hc4800746a9da7ff4E
0000000000007956 t _ZN81_$LT$bitcoin_hashes..sha256..HashEngine$u20$as$u20$bitcoin_hashes..HashEngine$GT$5input17hf49345f65130ce9bE
0000000000008024 t _ZN14bitcoin_hashes6sha2568Midstate10const_hash17h57317bc8012004b4E.llvm.441255102889972912
0000000000010528 t _ZN81_$LT$bitcoin_hashes..sha512..HashEngine$u20$as$u20$bitcoin_hashes..HashEngine$GT$5input17h9bc868d4392bd9acE
```
Total size: 32380 bytes
## With `small-hash` enabled
```
RUSTFLAGS='--cfg=bench -C opt-level=z' cargo bench --features small-hash
```
```
test hash160::benches::hash160_10 ... bench: 52 ns/iter (+/- 3) = 192 MB/s
test hash160::benches::hash160_1k ... bench: 4,817 ns/iter (+/- 286) = 212 MB/s
test hash160::benches::hash160_64k ... bench: 319,572 ns/iter (+/- 11,031) = 205 MB/s
test hmac::benches::hmac_sha256_10 ... bench: 54 ns/iter (+/- 2) = 185 MB/s
test hmac::benches::hmac_sha256_1k ... bench: 4,846 ns/iter (+/- 204) = 211 MB/s
test hmac::benches::hmac_sha256_64k ... bench: 319,114 ns/iter (+/- 4,451) = 205 MB/s
test ripemd160::benches::ripemd160_10 ... bench: 27 ns/iter (+/- 0) = 370 MB/s
test ripemd160::benches::ripemd160_1k ... bench: 2,358 ns/iter (+/- 150) = 434 MB/s
test ripemd160::benches::ripemd160_64k ... bench: 154,573 ns/iter (+/- 3,954) = 423 MB/s
test sha1::benches::sha1_10 ... bench: 41 ns/iter (+/- 1) = 243 MB/s
test sha1::benches::sha1_1k ... bench: 3,700 ns/iter (+/- 243) = 276 MB/s
test sha1::benches::sha1_64k ... bench: 231,039 ns/iter (+/- 13,989) = 283 MB/s
test sha256::benches::sha256_10 ... bench: 51 ns/iter (+/- 3) = 196 MB/s
test sha256::benches::sha256_1k ... bench: 4,823 ns/iter (+/- 182) = 212 MB/s
test sha256::benches::sha256_64k ... bench: 299,960 ns/iter (+/- 17,545) = 218 MB/s
test sha256d::benches::sha256d_10 ... bench: 52 ns/iter (+/- 2) = 192 MB/s
test sha256d::benches::sha256d_1k ... bench: 4,827 ns/iter (+/- 323) = 212 MB/s
test sha256d::benches::sha256d_64k ... bench: 302,844 ns/iter (+/- 15,796) = 216 MB/s
test sha512::benches::sha512_10 ... bench: 34 ns/iter (+/- 1) = 294 MB/s
test sha512::benches::sha512_1k ... bench: 3,002 ns/iter (+/- 123) = 341 MB/s
test sha512::benches::sha512_64k ... bench: 189,767 ns/iter (+/- 10,396) = 345 MB/s
test sha512_256::benches::sha512_256_10 ... bench: 34 ns/iter (+/- 1) = 294 MB/s
test sha512_256::benches::sha512_256_1k ... bench: 2,996 ns/iter (+/- 198) = 341 MB/s
test sha512_256::benches::sha512_256_64k ... bench: 192,024 ns/iter (+/- 8,181) = 341 MB/s
test siphash24::benches::siphash24_1ki ... bench: 1,081 ns/iter (+/- 65) = 947 MB/s
test siphash24::benches::siphash24_1ki_hash ... bench: 1,083 ns/iter (+/- 63) = 945 MB/s
test siphash24::benches::siphash24_1ki_hash_u64 ... bench: 1,084 ns/iter (+/- 63) = 944 MB/s
test siphash24::benches::siphash24_64ki ... bench: 67,237 ns/iter (+/- 4,185) = 974 MB/s
```
```
0000000000005384 t _ZN81_$LT$bitcoin_hashes..sha256..HashEngine$u20$as$u20$bitcoin_hashes..HashEngine$GT$5input17hae341658cf9b880bE
0000000000005608 t _ZN14bitcoin_hashes9ripemd16010HashEngine13process_block17h3276b13f1e9feef8E.llvm.13618235596061801146
0000000000005616 t _ZN14bitcoin_hashes6sha2568Midstate10const_hash17h3e6fbef64c15ee00E.llvm.7326223909590351031
0000000000005944 t _ZN81_$LT$bitcoin_hashes..sha512..HashEngine$u20$as$u20$bitcoin_hashes..HashEngine$GT$5input17h321a237bfbe5c0bbE
```
Total size: 22552 bytes
## Conclusion
On `aarch64` there's overall a ~30% improvement in size, although ripemd160 doesn't really shrink that much (and its performance also aren't impacted much with only a 6% slowdown). sha512 and sha256 instead are almost 40% slower with `small-hash` enabled.
I don't have performance numbers for other architectures, but in terms of size there was an even larger improvements on `thumbv7em-none-eabihf`, with a 52% size reduction overall:
```
Size Crate Name
25.3KiB bitcoin_hashes <bitcoin_hashes[fe467ef2aa3a1470]::sha512::HashEngine as bitcoin_hashes[fe467ef2aa3a1470]::HashEngine>::input
6.9KiB bitcoin_hashes <bitcoin_hashes[fe467ef2aa3a1470]::sha256::HashEngine as bitcoin_hashes[fe467ef2aa3a1470]::HashEngine>::input
4.8KiB bitcoin_hashes <bitcoin_hashes[fe467ef2aa3a1470]::ripemd160::HashEngine as bitcoin_hashes[fe467ef2aa3a1470]::HashEngine>::input
```
vs
```
Size Crate Name
9.5KiB bitcoin_hashes <bitcoin_hashes[974bb476ef905797]::sha512::HashEngine as bitcoin_hashes[974bb476ef905797]::HashEngine>::input
4.5KiB bitcoin_hashes <bitcoin_hashes[974bb476ef905797]::ripemd160::HashEngine>::process_block
3.8KiB bitcoin_hashes <bitcoin_hashes[974bb476ef905797]::sha256::HashEngine as bitcoin_hashes[974bb476ef905797]::HashEngine>::input
```
I'm assuming this is because on more limited architectures the compiler needs to use more instructions to move data in and out of registers (especially for sha512 which ideally would benefit from 64-bit registers), so reusing the code by moving it into functions saves a lot of those instructions.
Also note that the `const_hash` method on `sha256` causes the compiler to emit two independent implementations. I haven't looked into the code yet, maybe there's a way to merge them so that the non-const `process_block` calls into the const fn.
-----
Note: commits are unverified right now because I don't have the keys available, I will sign them after addressing the review comments.
ACKs for top commit:
apoelstra:
ACK f2c5f19557
tcharding:
ACK f2c5f19557
Tree-SHA512: 1d5eb56324c458660e2571e8cf59895dc31dae9c5427c7ed36f8a0e81ca2e9a0f39026f56b6803df03635cc8b66aee3bf5182d51ab8972d169d56bcfec33771c
546c0122d7 Add simd sha256 intrinsics for x86 machines (sanket1729)
Pull request description:
This is my first time dabbling into architecture specific code and simd. The algorithm is a word to word translation of the C code from 4899efc81d/sha256-x86.c .
Some benchmarks:
With simd
```
test sha256::benches::sha256_10 ... bench: 11 ns/iter (+/- 0) = 909 MB/s
test sha256::benches::sha256_1k ... bench: 712 ns/iter (+/- 2) = 1438 MB/s
test sha256::benches::sha256_64k ... bench: 45,597 ns/iter (+/- 189) = 1437 MB/s
```
Without simd
```
test sha256::benches::sha256_10 ... bench: 47 ns/iter (+/- 0) = 212 MB/s
test sha256::benches::sha256_1k ... bench: 4,243 ns/iter (+/- 17) = 241 MB/s
test sha256::benches::sha256_64k ... bench: 271,263 ns/iter (+/- 1,610) = 241 MB/s
```
ACKs for top commit:
apoelstra:
ACK 546c0122d7
tcharding:
ACK 546c0122d7
Tree-SHA512: 7167c900b77e63cf38135a3960cf9ac2615f73b2ef7020a12b5cc3f4c047910063ba9045217b9ecfa70f7de1eb0f02f2674f291bd023a853bad2b9162fae831e
When enabled this feature swaps the hash implementation of sha512,
sha256 and ripemd160 for a smaller (but also slower) one.
On embedded processors (Cortex-M4) it can lead to up to a 52% size
reduction, from around 37KiB for just the `process_block` methods of the
three hash functions to 17.8KiB.
154552e334 docs: Do not link to std::option::Option (Tobin C. Harding)
24843468c3 Remove rustdocs links to serde (Tobin C. Harding)
Pull request description:
Two minor patches to fix up docs links. These were originally done as part of #1880 but are unrelated so pushing them up separately.
ACKs for top commit:
apoelstra:
ACK 154552e334
RCasatta:
utACK 154552e334
Tree-SHA512: e45e1538c66b59d63a66898896927bb6c1336fb4c8515bb9e2204c8035870ef8e4a6fd32dfc83db2938afda67feb27c48989e382410f9e7ea7a967132941c720
We have just released the `hex-conservative` crate, we can now use it.
Do the following:
- Depend on `hex-conservative` in `bitcoin` and `hashes`
- Re-export `hex-conservative` as `hex` from both crate roots.
- Remove all the old hex code from `hashes`
- Fix all the import statements (makes up the bulk of the lines changed
in this patch)
Not totally necessary but since I went to the trouble of working out the
last working version add it to the docs so the next guy can grep for
`cargo update` to find them.
To help folk work out how to run the `hashes/embedded` test crate copy
over the `script` directory and an updated version of the `README` from
`embedded/bitcoin`.
In order to keep the embedded and schemacs test crates building when we
update their local transient dependencies we need to use a `patch`
section.
- For `bitcoin/embedded` add `patch` section for `internals`, `hashes`
already has an entry.
- For `hashes/embedded` add `patch` section for `internals`.
- For `hashes/extendend_tests/schemars` add `patch` section for
`internals`.
FTR for direct local dependencies we use a `path` field when specifying
the dependency.
We use two different methods for specifying local dependencies, `patch`
and also `path`. There does not seem to be a reason why we use both,
lets be uniform. Elect to use `patch` for all local crates.
8813a63ec9 internals: Bump version to 0.2.0 (Tobin C. Harding)
Pull request description:
In preparation for release bump the version and add a changelog entry. Includes updating the dependency in `bitcoin` and `hashes`.
ACKs for top commit:
apoelstra:
ACK 8813a63ec9
sanket1729:
utACK 8813a63ec9
Tree-SHA512: a9bd9d4d69cba21329f3f63a9948afe566bb97c8c65f5d46c329a696a814e9eb31372d378de1ecf0f43f0cb42f11d53dc51bc467223b34629e61315d48b39a29
In preparation for release bump the version and add a changelog entry.
Includes updating the dependency in `bitcoin` and `hashes` as well as
the minimal/recent lock files.
Recently we made the hash engine fields pub crate so that `sha512_256`
could construct a hash engine with different constants. We can make the
code slightly cleaner by adding a pub crate constructor and making the
fields private again.
Idea from Kixunil:
https://github.com/rust-bitcoin/rust-bitcoin/pull/1413#pullrequestreview-1197207593
aa7b3a7d0c ci: Remove stal DO_ALLOC_TESTS variable (Tobin C. Harding)
Pull request description:
We never enable the `DO_ALLOC_TESTS` variable, and hence never test the "alloc" feature in `hashes`.
Remove the `DO_ALLOC_TESTS` variable and add "alloc" to the `FEATURES` array.
ACKs for top commit:
yancyribbens:
ACK aa7b3a7d0c
apoelstra:
ACK aa7b3a7d0c
sanket1729:
utACK aa7b3a7d0c
Tree-SHA512: 461735242ec94786624a3653c3ea108d1a8712d5a77943f2ce54b44298624f6d4a43c98a0079782211e9a4b61ac87fbadd9c98608ca0ad82574c4a63b921776f
4dfaec952c hashes: Remove stale status badge (Tobin C. Harding)
Pull request description:
We do not use travis in our CI pipeline anymore, remove the stale badge.
ACKs for top commit:
yancyribbens:
ACK 4dfaec952c
apoelstra:
ACK 4dfaec952c
sanket1729:
utACK 4dfaec952c
Tree-SHA512: 6865c8cc51f90161ea643922df3bbf890811777e3dcbff9e464d6092f0d79a6ae2798d593f6a27e7f18b05ba66a765c871d4d01086e18b8480916573288afc0e
06afd52a12 Improve hashes::Error (Tobin C. Harding)
Pull request description:
We are trying to make error types stable on the way to v1.0
The current `hashes::Error` is a "general" enum error type with a single variant, better to use a struct and make the error usecase specific.
Improve the `hashes::Error` by doing:
- Make it a struct
- Rename to `FromSliceError`
- Move it to the crate root (remove `error` module)
Includes usage in `bitcoin`.
ACKs for top commit:
apoelstra:
ACK 06afd52a12
Kixunil:
ACK 06afd52a12
Tree-SHA512: 20a517daaf3e9e09744e2a65cde6e238c8f2d1224899a6c04142a3a4e635d54112b0a2e846d25256071bb27cb70f7482380f98e9a535a5498aa4c7dc0d52cc54
3717a549f9 hashes: Fix stale repository name (Tobin C. Harding)
Pull request description:
The repository name is stale since we moved the `hashes` crate into the `rust-bitcoin` repo a while ago.
ACKs for top commit:
apoelstra:
ACK 3717a549f9
Kixunil:
ACK 3717a549f9
Tree-SHA512: ac4553547f1912c8242e3b87d3cc8951598999b5512ad1b49494b3c504449939e0e60905d96464b22c71b67ca975d18814a92af6e0aa66ff4f46effb97ac0733
We never enable the `DO_ALLOC_TESTS` variable, and hence never test the
"alloc" feature in `hashes`.
Remove the `DO_ALLOC_TESTS` variable and add "alloc" to the `FEATURES`
array.
We are trying to make error types stable on the way to v1.0
The current `hashes::Error` is a "general" enum error type with a single
variant, better to use a struct and make the error usecase specific.
Improve the `hashes::Error` by doing:
- Make it a struct
- Rename to `FromSliceError`
- Move it to the crate root (remove `error` module)
Includes usage in `bitcoin`.
During the last round of releases (bitcoin 0.30, hashes 0.12) we removed
the `FromHex` implementation from all types except vecs and arrays. We
added `FromStr` impls for types that roundtrip with `Display`.
We never added a changelog mention to either `bitcoin` or `hashes`, lets
retroactively add an entry.
Fix: #1747
c4c64c0dc5 Test with minimal dependency versions (Martin Habovstiak)
d5655d503a Bump core2 dependency from 0.3.0 -> 0.3.2 (Tobin C. Harding)
Pull request description:
This is work originally done by Kixunil in #1272, I picked it up to help out. The only changes I made were rebasingg, updating the recent lock file, adding `--locked` to hashes contrib file, and adding a co-developed-by tag for accountability.
It could happen that we unknowingly depend on a new version of a crate without updating `Cargo.toml`. This could cause resolution issues for downstream users. It's also unclear for outsiders to know with which dependencies did we test the crate.
This change commits two lock files: `minimal` and `recent`. `minimal` contains minimal dependency versions, while `recent` contains dependency versions at the time of making the change.
Further, this adds CI jobs to test with both lock files, CI job for `internals` crate, removes old `serde` pinning and prints a warning if `recent` is no longer up to date. (We may have to override it somehow if any crate breaks MSRV.)
The documentation is also updated accordingly.
Closes#1230
ACKs for top commit:
apoelstra:
ACK c4c64c0dc5
Kixunil:
ACK c4c64c0dc5
Tree-SHA512: 7d386e96ab747f6a6bafeea828ac65bd8bb11975eaa3408acecac369cd2f235f6e9d4c57202be18a3dc2eeb2a2df532d73e4d35cd1f3fbf092eb6414c55b1524
It could happen that we unknowingly depend on a new version of a crate
without updating `Cargo.toml`. This could cause resolution issues for
downstream users. It's also unclear for outsiders to see which
dependencies we tested the crate with.
This change commits two lock files: `minimal` and `recent`. `minimal`
contains minimal depdendency versions, while `recent` contains
dependency versions at the time of making the change.
Further, this adds CI jobs to test with both lock files, CI job for
`internals` crate, removes old `serde` pinning and prints a warning if
`recent` is no longer up to date. (We may have to override it somehow if
any crate breaks MSRV.)
The documentation is also updated accordingly.
Co-developed-by: Tobin C. Harding <me@tobin.cc>
Closes#1230
Whether or not every file needs an explicit license comment is out of
scope for this patch; in the `bitcoin` crate we use SPDX identifiers
because they are a single line with no loss of "benefit" over any longer
form.
Use SPDX identifiers in `hashes`. Drop the mention of re-licensing code
from Apache to CC0-1 (because the original code was written by Andrew
as well as the copied code then if the argument ever comes up it can be
easily countered).
Seems we no longer need an explicit error handler, remove it.
I did not grok the reason (long thread link below) but just removed it
and checked that the embedded crates still ran correctly.
https://github.com/rust-lang/rust/issues/51540)
6c61e1019e Fix pinning (schemars and MSRV) (Tobin C. Harding)
c8e38d6a5a hashes: Implement JsonSchema for sha256t::Hash<T> (Tobin C. Harding)
Pull request description:
This has grown due to now including pinning work also done in https://github.com/rust-bitcoin/rust-bitcoin/pull/1736, I decided to do this because the PRs conflict and doing it all here saves accidentally getting out of sync. And https://github.com/rust-bitcoin/rust-bitcoin/pull/1764 requires this PR.
- Patch 1 is unchanged
- Patch 2 now fixes pinning in bitcoin and hashes CI scripts and in the docs of both as well as the manifest stuff relating to `schemars` - phew.
Fix: #1687
ACKs for top commit:
Kixunil:
ACK 6c61e1019e
apoelstra:
ACK 6c61e1019e
Tree-SHA512: eae4aa9700817bab6ad444e07709e8b1a4ffb1625e08be6ba399abde38bf6f8e5ea216a0836e2e26dfaddc76c392802cd016738ea6e753a1bca2584d9d2a9796
Done as is single patch to make sure all the docs and CI are in sync and
correct.
We currently pin the `schemars` dependency using `<=0.8.3` as well as a
the `dyn-clone` transient dependency in the manifest (`hashes` and the
extended test crate). This is incorrect because it makes usage of the
crate klunky (or possibly impossible) if downstream users wish to use a
later version of `schemars`.
Observe also that we do not have to pin `schemars`, we do however have to pin
the `serde` crate if either `serde` or `schemars` features are enabled.
Do so in CI and document in the readme file within hashes.
Currently we have a pin remaining from the old MSRV (`syn` due to use
of `matches!`).
Fix pinning by:
- Remove pin in manifest for `schemars`
- Fix pinning for MSRV in CI and docs (this includes documenting pinning
requirements for `schemars` feature because it is related to the other
pin of `serde`) in both `hashes` readme and main repo readme.
The Rust API guidelines state that macros should be evocative of the
output, which is a sensible recommendation. We already had this for
`hash_newtype!` macro but didn't for sha256t version.
This changes the macro to have this syntax:
```rust
sha256t_hash_newtype! {
// Order of these structs is fixed.
/// Optional documentation details here. Summary is auto-generated.
/*pub*/ struct Tag = raw(MIDSTATE_BYTES, LEN);
/// Documentation here
#[hash_newtype(forward)] // optional, default is backward
/*pub*/ struct HashType(/* attributes allowed here */ _);
}
```
Closes#1427
Computing hashes in const fn is useful for esily creating tags for
`sha256t`. This adds `const fn` implementation for `sha256::Hash` and
the algorithm for computing midstate of tagged hash in `const` context.
Part of #1427
a189942c64 Use doc_auto_cfg (Tobin C. Harding)
Pull request description:
If we use `#![cfg_attr(docsrs, feature(doc_auto_cfg))]` instead of `#![cfg_attr(docsrs, feature(doc_cfg))]` we no longer need to manually mark types with `#[cfg_attr(docsrs, doc(cfg(feature = "std")))]`.
Sweeeeeet.
Props to pezcore for the lesson :)
ACKs for top commit:
apoelstra:
ACK a189942c64
Kixunil:
ACK a189942c64
Tree-SHA512: 1ced1e09f5d1733b362b83ca650d3f52c89eb57e78e8437f74c496d89776548f8c50feab6750352342e2abe680434681de2c126ce36a81dda21397b9695d4d4e
If we use `#![cfg_attr(docsrs, feature(doc_auto_cfg))]` instead of
`#![cfg_attr(docsrs, feature(doc_cfg))]` we no longer need to manually
mark types with `#[cfg_attr(docsrs, doc(cfg(feature = "std")))]`.
Sweeeeeet.
The `hashes` module contains a bunch of arrays, mostly formatted with 8
hex bytes on a line; add `rustfmt::skip` to keep the formatting of
arrays as is.
Remove the exclude for the `hashes` crate. Do not run the formatter,
that will be done as a separate patch to aid review.
Tobin C. Harding
Andrew Poelstra
Alekos Filini
Riccardo Casatta
sanket1729
yancy
Martin Habovstiak
junderw