# Changelog for the Clash project

## 1.0.2
* Fixes issues:
  * [#895](https://github.com/clash-lang/clash-compiler/issues/895): VHDL type error when generating `Maybe (Vec 2 (Signed 8), Index 1)`
  * [#869](https://github.com/clash-lang/clash-compiler/issues/869): PLL is duplicated in Blinker.hs example

* Small fixes without issue reports:
  * Adds '--enable-shared-executables' for nix builds; this should make Clash run _much_ faster ([#894](https://github.com/clash-lang/clash-compiler/pull/894))
  * Fix blackbox issues causing Clash to generate invalid HDL ([#865](https://github.com/clash-lang/clash-compiler/pull/865))
  * Error on unparsed trailing garbage in JSON "files"

* Deprecations & removals:
  * Reset and Enable constructors are now only exported from Clash.Signal.Internal

## 1.0.1 *October 17th 2019*
* Fixes issues:
  * [#810](https://github.com/clash-lang/clash-compiler/issues/810): Verilog backend now correctly specifies type of `BitVector 1`
  * [#811](https://github.com/clash-lang/clash-compiler/issues/811): Improve module load behavior in clashi
  * [#439](https://github.com/clash-lang/clash-compiler/issues/439): Template Haskell splices and TopEntity annotations can now be used in clashi
  * [#818](https://github.com/clash-lang/clash-compiler/issues/818): Fixed various mistakes in tutorial
  * [#662](https://github.com/clash-lang/clash-compiler/issues/662): Clash will now constant specialize partially constant constructs
  * [#700](https://github.com/clash-lang/clash-compiler/issues/700): Check work content of expression in cast before warning users. Should eliminate a lot of (superfluous) warnings about "specializing on non work-free cast"s.
  * [#837](https://github.com/clash-lang/clash-compiler/issues/837): Blackboxes will now report clearer error messages if they're given unexpected arguments.

* Small fixes without issue reports:
  * Fix bug in `rnfX` defined for `Down` ([814fd52](https://github.com/clash-lang/clash-compiler/commit/814fd520191123be38af8ef28fc49130424f3b93))
  * Report blackbox name when encountering an error in 'setSym' ([#858](https://github.com/clash-lang/clash-compiler/pull/858))

## 1.0.0 *September 3rd 2019*
* 10x - 50x faster compile times
* New features:
  * API changes: check the migration guide at the end of `Clash.Tutorial`
  * All memory elements now have an (implicit) enable line; "Gated" clocks have
    been removed as the clock wasn't actually gated, but implemented as an
    enable line.
  * Circuit domains are now configurable in:
    * (old) The clock period
    * (new) Clock edge on which memory elements latch their inputs
      (rising edge or falling edge)
    * (new) Whether the reset port of a memory element is level sensitive
      (asynchronous reset) or edge sensitive (synchronous reset)
    * (new) Whether the reset port of a memory element is active-high or
      active-low (negated reset)
    * (new) Whether memory element power on in a configurable/defined state
      (common on FPGAs) or in an undefined state (ASICs)

    * See the [blog post](https://clash-lang.org/blog/0005-synthesis-domain/) on this new feature
  * Data types can now be given custom bit-representations: http://hackage.haskell.org/package/clash-prelude/docs/Clash-Annotations-BitRepresentation.html
  * Annotate expressions with attributes that persist in the generated HDL,
    e.g. synthesis directives: http://hackage.haskell.org/package/clash-prelude/docs/Clash-Annotations-SynthesisAttributes.html
  * Control (System)Verilog module instance, and VHDL entity instantiation names
    in generated code: http://hackage.haskell.org/package/clash-prelude/docs/Clash-Magic.html
  * Much improved infrastructure for handling of unknown values: defined spine,
    but unknown leafs: http://hackage.haskell.org/package/clash-prelude/docs/Clash-XException.html#t:NFDataX
  * Experimental: Multiple hidden clocks. Can be enabled by compiling
    `clash-prelude` with `-fmultiple-hidden`
  * Experimental: Limited GADT support (pattern matching on vectors, or custom
    GADTs as longs as their usage can be statically removed; no support of
    recursive GADTs)
  * Experimental: Use regular Haskell functions to generate HDL black boxes for
    primitives (in an addition to existing string templates for HDL black boxes)
    See for example: http://hackage.haskell.org/package/clash-lib/docs/Clash-Primitives-Intel-ClockGen.html

* Fixes issues:
  * [#316](https://github.com/clash-lang/clash-compiler/issues/316)
  * [#319](https://github.com/clash-lang/clash-compiler/issues/319)
  * [#323](https://github.com/clash-lang/clash-compiler/issues/323)
  * [#324](https://github.com/clash-lang/clash-compiler/issues/324)
  * [#329](https://github.com/clash-lang/clash-compiler/issues/329)
  * [#331](https://github.com/clash-lang/clash-compiler/issues/331)
  * [#332](https://github.com/clash-lang/clash-compiler/issues/332)
  * [#335](https://github.com/clash-lang/clash-compiler/issues/335)
  * [#348](https://github.com/clash-lang/clash-compiler/issues/348)
  * [#349](https://github.com/clash-lang/clash-compiler/issues/349)
  * [#350](https://github.com/clash-lang/clash-compiler/issues/350)
  * [#351](https://github.com/clash-lang/clash-compiler/issues/351)
  * [#352](https://github.com/clash-lang/clash-compiler/issues/352)
  * [#353](https://github.com/clash-lang/clash-compiler/issues/353)
  * [#358](https://github.com/clash-lang/clash-compiler/issues/358)
  * [#359](https://github.com/clash-lang/clash-compiler/issues/359)
  * [#363](https://github.com/clash-lang/clash-compiler/issues/363)
  * [#364](https://github.com/clash-lang/clash-compiler/issues/364)
  * [#365](https://github.com/clash-lang/clash-compiler/issues/365)
  * [#371](https://github.com/clash-lang/clash-compiler/issues/371)
  * [#372](https://github.com/clash-lang/clash-compiler/issues/372)
  * [#373](https://github.com/clash-lang/clash-compiler/issues/373)
  * [#378](https://github.com/clash-lang/clash-compiler/issues/378)
  * [#380](https://github.com/clash-lang/clash-compiler/issues/380)
  * [#381](https://github.com/clash-lang/clash-compiler/issues/381)
  * [#382](https://github.com/clash-lang/clash-compiler/issues/382)
  * [#383](https://github.com/clash-lang/clash-compiler/issues/383)
  * [#387](https://github.com/clash-lang/clash-compiler/issues/387)
  * [#393](https://github.com/clash-lang/clash-compiler/issues/393)
  * [#396](https://github.com/clash-lang/clash-compiler/issues/396)
  * [#398](https://github.com/clash-lang/clash-compiler/issues/398)
  * [#399](https://github.com/clash-lang/clash-compiler/issues/399)
  * [#401](https://github.com/clash-lang/clash-compiler/issues/401)
  * [#403](https://github.com/clash-lang/clash-compiler/issues/403)
  * [#407](https://github.com/clash-lang/clash-compiler/issues/407)
  * [#412](https://github.com/clash-lang/clash-compiler/issues/412)
  * [#413](https://github.com/clash-lang/clash-compiler/issues/413)
  * [#420](https://github.com/clash-lang/clash-compiler/issues/420)
  * [#422](https://github.com/clash-lang/clash-compiler/issues/422)
  * [#423](https://github.com/clash-lang/clash-compiler/issues/423)
  * [#424](https://github.com/clash-lang/clash-compiler/issues/424)
  * [#438](https://github.com/clash-lang/clash-compiler/issues/438)
  * [#450](https://github.com/clash-lang/clash-compiler/issues/450)
  * [#452](https://github.com/clash-lang/clash-compiler/issues/452)
  * [#455](https://github.com/clash-lang/clash-compiler/issues/455)
  * [#460](https://github.com/clash-lang/clash-compiler/issues/460)
  * [#461](https://github.com/clash-lang/clash-compiler/issues/461)
  * [#463](https://github.com/clash-lang/clash-compiler/issues/463)
  * [#468](https://github.com/clash-lang/clash-compiler/issues/468)
  * [#475](https://github.com/clash-lang/clash-compiler/issues/475)
  * [#476](https://github.com/clash-lang/clash-compiler/issues/476)
  * [#500](https://github.com/clash-lang/clash-compiler/issues/500)
  * [#507](https://github.com/clash-lang/clash-compiler/issues/507)
  * [#512](https://github.com/clash-lang/clash-compiler/issues/512)
  * [#516](https://github.com/clash-lang/clash-compiler/issues/516)
  * [#517](https://github.com/clash-lang/clash-compiler/issues/517)
  * [#526](https://github.com/clash-lang/clash-compiler/issues/526)
  * [#556](https://github.com/clash-lang/clash-compiler/issues/556)
  * [#560](https://github.com/clash-lang/clash-compiler/issues/560)
  * [#566](https://github.com/clash-lang/clash-compiler/issues/566)
  * [#567](https://github.com/clash-lang/clash-compiler/issues/567)
  * [#569](https://github.com/clash-lang/clash-compiler/issues/569)
  * [#573](https://github.com/clash-lang/clash-compiler/issues/573)
  * [#575](https://github.com/clash-lang/clash-compiler/issues/575)
  * [#581](https://github.com/clash-lang/clash-compiler/issues/581)
  * [#582](https://github.com/clash-lang/clash-compiler/issues/582)
  * [#586](https://github.com/clash-lang/clash-compiler/issues/586)
  * [#588](https://github.com/clash-lang/clash-compiler/issues/588)
  * [#591](https://github.com/clash-lang/clash-compiler/issues/591)
  * [#596](https://github.com/clash-lang/clash-compiler/issues/596)
  * [#601](https://github.com/clash-lang/clash-compiler/issues/601)
  * [#607](https://github.com/clash-lang/clash-compiler/issues/607)
  * [#629](https://github.com/clash-lang/clash-compiler/issues/629)
  * [#637](https://github.com/clash-lang/clash-compiler/issues/637)
  * [#644](https://github.com/clash-lang/clash-compiler/issues/644)
  * [#647](https://github.com/clash-lang/clash-compiler/issues/647)
  * [#661](https://github.com/clash-lang/clash-compiler/issues/661)
  * [#668](https://github.com/clash-lang/clash-compiler/issues/668)
  * [#677](https://github.com/clash-lang/clash-compiler/issues/677)
  * [#678](https://github.com/clash-lang/clash-compiler/issues/678)
  * [#682](https://github.com/clash-lang/clash-compiler/issues/682)
  * [#691](https://github.com/clash-lang/clash-compiler/issues/691)
  * [#703](https://github.com/clash-lang/clash-compiler/issues/703)
  * [#713](https://github.com/clash-lang/clash-compiler/issues/713)
  * [#715](https://github.com/clash-lang/clash-compiler/issues/715)
  * [#727](https://github.com/clash-lang/clash-compiler/issues/727)
  * [#730](https://github.com/clash-lang/clash-compiler/issues/730)
  * [#736](https://github.com/clash-lang/clash-compiler/issues/736)
  * [#738](https://github.com/clash-lang/clash-compiler/issues/738)

## 0.99.3 *July 28th 2018*
* Fixes bugs:
  * Evaluator recognizes `Bit` literals [#329](https://github.com/clash-lang/clash-compiler/issues/329)
  * Use existential type-variables in context of GADT pattern match
  * Do not create zero-bit temporary variables in generated HDL
  * Use correct arguments in nested primitives [#323](https://github.com/clash-lang/clash-compiler/issues/329)
  * Zero-constructor data type needs 0 bits [#238](https://github.com/clash-lang/clash-compiler/issues/238)
  * Create empty component when result needs 0 bits
  * Evaluator performs BigNat arithmetic

* Features:
  * Bundle and BitPack instances up to and including 62-tuples
  * Handle undefined writes to RAM properly
  * Handle undefined clock enables properly


## 0.99.1 *May 12th 2018*
* Allow `~NAME[N]` tag inside `~GENSYM[X]`
* Support HDL record selector generation [#313](https://github.com/clash-lang/clash-compiler/pull/313)
* `InlinePrimitive` support: specify HDL primitives inline with Haskell code
* Support for `ghc-typelits-natnormalise-0.6.1`
* `Lift` instances for `TopEntity` and `PortName`
* `InlinePrimitive` support: specify HDL primitives inline with Haskell code

## 0.99 *March 31st 2018*
* New features:
  * Major API overhaul: check the migration guide at the end of `Clash.Tutorial`
  * New features:
    * Explicit clock and reset arguments
    * Rename `CLaSH` to `Clash`
    * Implicit/`Hidden` clock and reset arguments using a combination of
    `reflection` and `ImplicitParams`.
    * Large overhaul of `TopEntity`  annotations
    * PLL and other clock sources can now be instantiated using regular functions:
    `Clash.Intel.ClockGen` and `Clash.Xilinx.ClockGen`.
    * DDR registers:
      * Generic/ASIC: `Clash.Explicit.DDR`
      * Intel: `Clash.Intel.DDR`
      * Xilinx: `Clash.Intel.Xilinx`
  * `Bit` is now a `newtype` instead of a `type` synonym and will be mapped to
    a HDL scalar instead of an array of one (e.g `std_logic` instead of
    `std_logic_vector(0 downto 0)`)
  * Hierarchies with multiple synthesisable boundaries by allowing more than one
    function in scope to have a `Synthesize` annotation.
    * Local caching of functions with a `Synthesize` annotation
  * `Bit` type is mapped to a HDL scalar type (e.g. `std_logic` in VHDL)
  * Improved name preservation
  * Zero-bit values are filtered out of the generated HDL
  * Improved compile-time computation
* Many bug fixes

## Older versions
Check out:
 * https://github.com/clash-lang/clash-compiler/blob/3649a2962415ea8ca2d6f7f5e673b4c14de26b4f/clash-prelude/CHANGELOG.md
 * https://github.com/clash-lang/clash-compiler/blob/3649a2962415ea8ca2d6f7f5e673b4c14de26b4f/clash-lib/CHANGELOG.md
 * https://github.com/clash-lang/clash-compiler/blob/3649a2962415ea8ca2d6f7f5e673b4c14de26b4f/clash-ghc/CHANGELOG.md