# Changelog

The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).

## [Unreleased]

## [2.2.1] - 2023-01-08 <a name="2.2.1"></a>
### Changed
- Reduced unnecessary bounds checks for SIMD operations on slices. By [@Shnatsel].
- Further slice conversion optimizations for slices. Resolves [#66].

## [2.2.0] - 2022-12-30 <a name="2.2.0"></a>
### Added
- Add `serialize_as_f32` and `serialize_as_string` functions when `serde` cargo feature is enabled.
  They allowing customizing the serialization by using 
  `#[serde(serialize_with="f16::serialize_as_f32")]` attribute in serde derive macros. Closes [#60].
- Deserialize now supports deserializing from `f32`, `f64`, and string values in addition to its
  previous default deserialization. Closes [#60].

### Changed
- Add `#[inline]` on fallback functions, which improved conversion execution on non-nightly rust 
  by up to 50%. By [@Shnatsel].

## [2.1.0] - 2022-07-18 <a name="2.1.0"></a>
### Added
- Add support for target_arch `spirv`. Some traits and functions are unavailble on this
  architecture. By [@charles-r-earp].
- Add `total_cmp` method to both float types. Closes [#55], by [@joseluis].

## [2.0.0] - 2022-06-21 <a name="2.0.0"></a>
### Changed
- **Breaking Change** Minimum supported Rust version is now 1.58.
- **Breaking Change** `std` is now enabled as a default cargo feature. Disable default features to
  continue using `no_std` support.
- Migrated to Rust Edition 2021.
- Added `#[must_use]` attributes to functions, as appropriate.

### Fixed
- Fix a soundness bug with `slice::as_ptr` not correctly using mutable reference. By [@Nilstrieb].

### Added
- Added `const` conversion methods to both `f16` and `bf16`. These methods never use hardware
  intrinsics, unlike the current conversion methods, which is why they are separated into new
  methods. The following `const` methods were added:
  - `from_f32_const`
  - `from_f64_const`
  - `to_f32_const`
  - `to_f64_const`
- Added `Neg` trait support for borrowed values `&f16` and `&bf16`. By [@pthariensflame].
- Added `AsPrimitive` implementations from and to self, `usize`, and `isize`. By [@kali].

### Removed
- **Breaking Change** The deprecated `serialize` cargo feature has been removed. Use `serde` cargo
  feature instead.
- **Breaking Change** The deprecated `consts` module has been removed. Use associated constants on
  `f16` instead.
- **Breaking Change** The following deprecated functions have been removed:
  - `f16::as_bits`
  - `slice::from_bits_mut`
  - `slice::to_bits_mut`
  - `slice::from_bits`
  - `slice::to_bits`
  - `vec::from_bits`
  - `vec::to_bits`

## [1.8.2] - 2021-10-22 <a name="1.8.2"></a>
### Fixed
- Remove cargo resolver=2 from manifest to resolve errors in older versions of Rust that still
  worked with 1.8.0. Going forward, MSRV increases will be major version increases. Fixes [#48].

## [1.8.1] - 2021-10-21 - **Yanked** <a name="1.8.1"></a>
### ***Yanked***
*Not recommended due to introducing compilation error in Rust versions that worked with 1.8.0.*
### Changed
- Now uses cargo resolver version 2 to prevent dev-dependencies from enabling `std` feature on
  optional dependencies.

### Fixed
- Fixed compile failure when `std` feature is not enabled and `num-traits` is enabled under new
  resolver. Now properly uses `libm` num-traits feature.

## [1.8.0] - 2021-10-13 <a name="1.8.0"></a>
### Changed
- Now always implements `Add`, `Div`, `Mul`, `Neg`, `Rem`, and `Sub` traits. 
  Previously, these were only implemented under the `num-traits` feature. Keep in mind they still
  convert to `f32` and back in the implementation.
- Minimum supported Rust version is now 1.51.
- Made crate package [REUSE compliant](https://reuse.software/).
- Docs now use intra-doc links instead of manual (and hard to maintain) links.
- The following methods on both `f16` and `bf16` are now `const`:
  - `to_le_bytes`
  - `to_be_bytes`
  - `to_ne_bytes`
  - `from_le_bytes`
  - `from_be_bytes`
  - `from_ne_bytes`
  - `is_normal`
  - `classify`
  - `signum`

### Added
- Added optional implementations of `zerocopy` traits `AsBytes` and `FromBytes`
  under `zerocopy` cargo feature. By [@samcrow].
- Implemented the `core::iter::Product` and `core::iter::Sum` traits, with the same caveat as above
  about converting to `f32` and back under the hood.
- Added new associated const `NEG_ONE` to both `f16` and `bf16`.
- Added the following new methods on both `f16` and `bf16`:
  - `copysign`
  - `max`
  - `min`
  - `clamp`

### Fixed
- Fixed a number of minor lints discovered due to improved CI.

## [1.7.1] - 2021-01-17 <a name="1.7.1"></a>
### Fixed
- Docs.rs now generates docs for `bytemuck` and `num-traits` optional features.

## [1.7.0] - 2021-01-17 <a name="1.7.0"></a>
### Added
- Added optional implementations of `bytemuck` traits `Zeroable` and `Pod` under `bytemuck` cargo
  feature. By [@charles-r-earp].
- Added optional implementations of `num-traits` traits `ToPrimitive` and `FromPrimitive` under
  `num-traits` cargo feature. By [@charles-r-earp].
- Added implementations of `Binary`, `Octal`, `LowerHex`, and `UpperHex` string format traits to
  format raw `f16`/`bf16` bytes to string.

### Changed
- `Debug` trait implementation now formats `f16`/`bf16` as float instead of raw bytes hex. Use newly
  implemented formatting traits to format in hex instead of `Debug`. Fixes [#37].


## [1.6.0] - 2020-05-09 <a name="1.6.0"></a>
### Added
- Added `LOG2_10` and `LOG10_2` constants to both `f16` and `bf16`, which were added to `f32` and
  `f64` in the standard library in 1.43.0. By [@tspiteri].
- Added `to_le/be/ne_bytes` and `from_le/be/ne_bytes` to both `f16` and `bf16`, which were added to
  the standard library in 1.40.0. By [@bzm3r].

## [1.5.0] - 2020-03-03 <a name="1.5.0"></a>
### Added
- Added the `alloc` feature to support the `alloc` crate in `no_std` environments. By [@zserik]. The
  `vec` module is now available with either `alloc` or `std` feature.

## [1.4.1] - 2020-02-10 <a name="1.4.1"></a>
### Fixed
- Added `#[repr(transparent)]` to `f16`/`bf16` to remove undefined behavior. By [@jfrimmel].

## [1.4.0] - 2019-10-13 <a name="1.4.0"></a>
### Added
- Added a `bf16` type implementing the alternative
  [`bfloat16`](https://en.wikipedia.org/wiki/Bfloat16_floating-point_format) 16-bit floating point
  format. By [@tspiteri].
- `f16::from_bits`, `f16::to_bits`, `f16::is_nan`, `f16::is_infinite`, `f16::is_finite`,
  `f16::is_sign_positive`, and `f16::is_sign_negative` are now `const` fns.
- `slice::HalfBitsSliceExt` and `slice::HalfBitsSliceExt` extension traits have been added for
  performing efficient reinterpret casts and conversions of slices to and from `[f16]` and
  `[bf16]`.  These traits will use hardware SIMD conversion instructions when available and the
  `use-intrinsics` cargo feature is enabled.
- `vec::HalfBitsVecExt` and `vec::HalfFloatVecExt` extension traits have been added for
   performing efficient reinterpret casts to and from `Vec<f16>` and `Vec<bf16>`. These traits
   are only available with the `std` cargo feature.
- `prelude` has been added, for easy importing of most common functionality. Currently the
  prelude imports `f16`, `bf16`, and the new slice and vec extension traits.
- New associated constants on `f16` type to replace deprecated `consts` module.

### Fixed
- Software conversion (when not using `use-intrinsics` feature) now matches hardware rounding
  by rounding to nearest, ties to even. Fixes [#24], by [@tspiteri].
- NaN value conversions now behave like `f32` to `f64` conversions, retaining sign. Fixes [#23],
  by [@tspiteri].

### Changed
- Minimum rustc version bumped to 1.32.
- Runtime target host feature detection is now used if both `std` and `use-intrinsics` features are
  enabled and the compile target host does not support required features.
- When `use-intrinsics` feature is enabled, will now always compile and run without error correctly
  regardless of compile target options.

### Deprecated
- `consts` module and all its constants have been deprecated; use the associated constants on `f16`
  instead.
- `slice::from_bits` has been deprecated; use `slice::HalfBitsSliceExt::reinterpret_cast` instead.
- `slice::from_bits_mut` has been deprecated; use `slice::HalfBitsSliceExt::reinterpret_cast_mut`
  instead.
- `slice::to_bits` has been deprecated; use `slice::HalfFloatSliceExt::reinterpret_cast` instead.
- `slice::to_bits_mut` has been deprecated; use `slice::HalfFloatSliceExt::reinterpret_cast_mut`
  instead.
- `vec::from_bits` has been deprecated; use `vec::HalfBitsVecExt::reinterpret_into` instead.
- `vec::to_bits` has been deprecated; use `vec::HalfFloatVecExt::reinterpret_into` instead.

## [1.3.1] - 2019-10-04 <a name="1.3.1"></a>
### Fixed
- Corrected values of constants `EPSILON`, `MAX_10_EXP`, `MAX_EXP`, `MIN_10_EXP`, and `MIN_EXP`
  in `consts` module, as well as setting `consts::NAN` to match value of `f32::NAN` converted to
  `f16`. By [@tspiteri].

## [1.3.0] - 2018-10-02 <a name="1.3.0"></a>
### Added
- `slice::from_bits_mut` and `slice::to_bits_mut` for conversion between mutable `u16` and `f16`
  slices. Fixes [#16], by [@johannesvollmer].

## [1.2.0] - 2018-09-03 <a name="1.2.0"></a>
### Added
- `slice` and optional `vec` (only included with `std` feature) modules for conversions between
  `u16` and `f16` buffers. Fixes [#14], by [@johannesvollmer].
- `to_bits` added to replace `as_bits`. Fixes [#12], by [@tspiteri].
### Fixed
- `serde` optional dependency no longer uses its default `std` feature.
### Deprecated
- `as_bits` has been deprecated; use `to_bits` instead.
- `serialize` cargo feature is deprecated; use `serde` instead.

## [1.1.2] - 2018-07-12 <a name="1.1.2"></a>
### Fixed
- Fixed compilation error in 1.1.1 on rustc < 1.27, now compiles again on rustc >= 1.10. Fixes
  [#11].

## [1.1.1] - 2018-06-24 - **Yanked** <a name="1.1.1"></a>
### ***Yanked***
*Not recommended due to introducing compilation error on rustc versions prior to 1.27.*
### Fixed
- Fix subnormal float conversions when `use-intrinsics` is not enabled. By [@Moongoodboy-K].

## [1.1.0] - 2018-03-17 <a name="1.1.0"></a>
### Added
- Made `to_f32` and `to_f64` public. Fixes [#7], by [@PSeitz].

## [1.0.2] - 2018-01-12 <a name="1.0.2"></a>
### Changed
- Update behavior of `is_sign_positive` and `is_sign_negative` to match the IEEE754 conforming
  behavior of the standard library since Rust 1.20.0. Fixes [#3], by [@tspiteri].
- Small optimization on `is_nan` and `is_infinite` from [@tspiteri].
### Fixed
- Fix comparisons of +0 to -0 and comparisons involving negative numbers. Fixes [#2], by
  [@tspiteri].
- Fix loss of sign when converting `f16` and `f32` to `f16`, and case where `f64` NaN could be
  converted to `f16` infinity instead of NaN. Fixes [#5], by [@tspiteri].

## [1.0.1] - 2017-08-30 <a name="1.0.1"></a>
### Added
- More README documentation.
- Badges and categories in crate metadata.
### Changed
- `serde` dependency updated to 1.0 stable.
- Writing changelog manually.

## [1.0.0] - 2017-02-03 <a name="1.0.0"></a>
### Added
- Update to `serde` 0.9 and stable Rust 1.15 for `serialize` feature.

## [0.1.1] - 2017-01-08 <a name="0.1.1"></a>
### Added
- Add `serde` support under new `serialize` feature.
### Changed
- Use `no_std` for crate by default.

## 0.1.0 - 2016-03-17 <a name="0.1.0"></a>
### Added
- Initial release of `f16` type.

[#2]: https://github.com/starkat99/half-rs/issues/2
[#3]: https://github.com/starkat99/half-rs/issues/3
[#5]: https://github.com/starkat99/half-rs/issues/5
[#7]: https://github.com/starkat99/half-rs/issues/7
[#11]: https://github.com/starkat99/half-rs/issues/11
[#12]: https://github.com/starkat99/half-rs/issues/12
[#14]: https://github.com/starkat99/half-rs/issues/14
[#16]: https://github.com/starkat99/half-rs/issues/16
[#23]: https://github.com/starkat99/half-rs/issues/23
[#24]: https://github.com/starkat99/half-rs/issues/24
[#37]: https://github.com/starkat99/half-rs/issues/37
[#48]: https://github.com/starkat99/half-rs/issues/48
[#55]: https://github.com/starkat99/half-rs/issues/55
[#60]: https://github.com/starkat99/half-rs/issues/60
[#66]: https://github.com/starkat99/half-rs/issues/66

[@tspiteri]: https://github.com/tspiteri
[@PSeitz]: https://github.com/PSeitz
[@Moongoodboy-K]: https://github.com/Moongoodboy-K
[@johannesvollmer]: https://github.com/johannesvollmer
[@jfrimmel]: https://github.com/jfrimmel
[@zserik]: https://github.com/zserik
[@bzm3r]: https://github.com/bzm3r
[@charles-r-earp]: https://github.com/charles-r-earp
[@samcrow]: https://github.com/samcrow
[@pthariensflame]: https://github.com/pthariensflame
[@kali]: https://github.com/kali
[@Nilstrieb]: https://github.com/Nilstrieb
[@joseluis]: https://github.com/joseluis
[@Shnatsel]: https://github.com/Shnatsel


[Unreleased]: https://github.com/starkat99/half-rs/compare/v2.2.1...HEAD
[2.2.1]: https://github.com/starkat99/half-rs/compare/v2.2.0...v2.2.1
[2.2.0]: https://github.com/starkat99/half-rs/compare/v2.1.0...v2.2.0
[2.1.0]: https://github.com/starkat99/half-rs/compare/v2.0.0...v2.1.0
[2.0.0]: https://github.com/starkat99/half-rs/compare/v1.8.2...v2.0.0
[1.8.2]: https://github.com/starkat99/half-rs/compare/v1.8.1...v1.8.2
[1.8.1]: https://github.com/starkat99/half-rs/compare/v1.8.0...v1.8.1
[1.8.0]: https://github.com/starkat99/half-rs/compare/v1.7.1...v1.8.0
[1.7.1]: https://github.com/starkat99/half-rs/compare/v1.7.0...v1.7.1
[1.7.0]: https://github.com/starkat99/half-rs/compare/v1.6.0...v1.7.0
[1.6.0]: https://github.com/starkat99/half-rs/compare/v1.5.0...v1.6.0
[1.5.0]: https://github.com/starkat99/half-rs/compare/v1.4.1...v1.5.0
[1.4.1]: https://github.com/starkat99/half-rs/compare/v1.4.0...v1.4.1
[1.4.0]: https://github.com/starkat99/half-rs/compare/v1.3.1...v1.4.0
[1.3.1]: https://github.com/starkat99/half-rs/compare/v1.3.0...v1.3.1
[1.3.0]: https://github.com/starkat99/half-rs/compare/v1.2.0...v1.3.0
[1.2.0]: https://github.com/starkat99/half-rs/compare/v1.1.2...v1.2.0
[1.1.2]: https://github.com/starkat99/half-rs/compare/v1.1.1...v1.1.2
[1.1.1]: https://github.com/starkat99/half-rs/compare/v1.1.0...v1.1.1
[1.1.0]: https://github.com/starkat99/half-rs/compare/v1.0.2...v1.1.0
[1.0.2]: https://github.com/starkat99/half-rs/compare/v1.0.1...v1.0.2
[1.0.1]: https://github.com/starkat99/half-rs/compare/v1.0.0...v1.0.1
[1.0.0]: https://github.com/starkat99/half-rs/compare/v0.1.1...v1.0.0
[0.1.1]: https://github.com/starkat99/half-rs/compare/v0.1.0...v0.1.1
