0.15.7

Added

• Faster index calculations for very tight GPU kernels (such as the
  ones corresponding to 2D tiling).

• scan with vectorised operators (e.g. map2 (+)) is now faster
  in some cases.

• The C API has now been documented and stabilized, including
  obtaining profiling information (although this is still
  unstructured).

Fixed

• Fixed some cases of missing fusion (#953).

• Context deinitialisation is now more complete, and should not leak
  memory (or at least not nearly as much, if any). This makes it
  viable to repeatedly create and free Futhark contexts in the same
  process (although this can still be quite slow).

0.15.6

Added

• Binary operators now act as left-to-right sequence points with
  respect to size types.

• futhark bench now has more colourful and hopefully readable
  output.

• The compiler is now about 30% faster for most nontrivial programs.
  This is due to parallelising the inlining stage, and tweaking the
  default configuration of the Haskell RTS.

• futhark dataset is now about 8-10x faster.

Fixed

• Fixed some errors regarding constants (#941).

• Fixed a few missing type checker cases for sum types (#938).

• Fix OOB write in CUDA backend runtime code (#950).

0.15.5

Added

• reduce_by_index with f32-addition is now approximately 2x
  faster in the CUDA backend.

Fixed

• Fixed kernel extractor bug in if-interchange (#921).

• Fixed some cases of malformed kernel code generation (#922).

• Fixed rare memory corruption bug involving branches returning
  arrays (#923).

• Fixed spurious warning about entry points involving opaque return
  types, where the type annotations are put on a higher-order return
  type.

• Fixed incorrect size type checking for sum types in negative
  position with unknown constructors (#927).

• Fixed loop interchange for permuted sequential loops with more
  than one outer parallel loop (#928).

• Fixed a type checking bug for branches returning incomplete sum
  types (#931).

0.15.4

Added

• futhark pkg now shells out to curl for HTTP requests.

• futhark doc now supports proper GitHub-flavored Markdown, as it
  uses the cmark-gfm library internally.

• Top-level constants are now executed only once per program
  instance. This matters when Futhark is used to generate library
  code.

• futhark autotune is better at handling degrees of parallelism
  that assume multiple magnitudes during a single run.

• futhark pkg now uses curl to retrieve packages.

• Type errors are now printed in red for better legibility (thanks
  to @mxxo!).

Fixed

• Fixed incorrect handling of opaques in entry point return types.

• futhark pkg now works properly with GitLab (#899).

0.15.3

Added

• scan now supports operators whose operands are arrays. They are
  significantly slower than primitive-typed scans, so avoid them if
  at all possible.

• Precomputed constants are now handled much more efficiently.

• Certain large programs that rely heavily on inlining now compile
  orders of magnitude faster.

Fixed

• Some fixes to complicated module expressions.

• futhark pkg should no longer crash uncontrollably on network
  errors (#894).

• Fixed local open in interpreter (#887).

• Fix error regarding entry points that called other entry points
  which contained local functions (#895).

• Fix loading OpenCL kernels from a binary.

0.15.2

Fixed

• Fix a REPL regression that made it unable to handle overloaded
  types (such as numeric literals, oops).

• The uniqueness of a record is now the minimum of the uniqueness of
  any of its elements (#870).

• Bug in causality checking has been fixed (#872).

• Invariant memory allocations in scan/reduce operators are now supported.

• futhark run now performs more type checking on entry point input (#876).

• Compiled Futhark programs now check for EOF after the last input
  argument has been read (#877).

• Fixed a bug in loop type checking that prevented the result from
  ever aliasing the initial parameter values (#879).

0.15.1

Added

• Futhark now type-checks size annotations using a size-dependent
  type system.

• The parallel code generators can now handle bounds checking and
  other safety checks.

• Integer division by zero is now properly safety-checked and
  produces an error message.

• Integer exponentiation with negative exponent is now properly
  safety-checked and produces an error message.

• Serious effort has been put into improving type errors.

• reduce_by_index may be somewhat faster for complex operators on
  histograms that barely fit in local memory.

• Improved handling of in-place updates of multidimensional arrays
  nested in map. These are now properly parallelised.

• Added concat_to and flatten_to functions to prelude.

• Added indices function to the prelude.

• futhark check and all compilers now take a -w option for
  disabling warnings.

• futhark bench now accepts --pass-compiler-option.

• The integer modules now have mad_hi and mul_hi functions for
  getting the upper part of multiplications. Thanks to @porcuquine for the contribution!

• The f32 and f64 modules now also define sinh, cosh,
  tanh, asinh, acosh, and atanh functions.

• The f32 and f64 modules now also define fma and mad
  functions.

Removed

• Removed update, split2, intersperse, intercalate, pick,
  steps, and range from the prelude.

Changed

• "futlib" is now called "prelude", and it is now an error to
  import it explicitly.

Fixed

• Corrected address calculations in csharp backend.

• The C backends are now more careful about generating overflowing
  integer operations (since this is undefined behaviour in C, but
  defined in Futhark).

• futhark dataset no longer crashes uncontrollably when used
  incorrectly (#849).

0.14.1

Added

• The optimiser is now somewhat better at removing unnecessary
  copies of array slices.

• futhark bench and futhark test now take a --concurrency
  option for limiting how many threads are used for housekeeping
  tasks. Set this to a low value if you run out of memory.

• random test blocks are now allowed to contain integer literals
  with type suffixes.

• :frame <n> command for futhark repl for inspecting the stack.

• e :> t notation, which means the same as e : t for now, but
  will have looser constraints in the future.

• Size-lifted type abbreviations can be declared with type~ and
  size-lifted type parameters with '~. These currently have no
  significant difference from fully lifted types.

Changed

• Tuples are now 0-indexed (#821, which also includes a conversion
  script).

• Invalid ranges like 1..<0 now produce a run-time error instead
  of an empty array.

• Record updates (r with f = e) now require r to have a
  completely known type up to f. This is a restriction that will
  hopefully be lifted in the future.

• The backtrace format has changed to be innermost-first, like
  pretty much all other languages.

• Value specs must now explicitly quantify all sizes of function
  parameters. Instead of

  val sum: []t -> t
  

  you must write

  val sum [n]: [n]t -> t
  

• futhark test now once again numbers un-named data sets from 0
  rather than from 1. This fits a new general principle of always
  numbering from 0 in Futhark.

• Type abbreviations declared with type may no longer contain
  functions or anonymous sizes in their definition. Use type^ for
  these cases. Just a warning for now, but will be an error in the
  future.

Fixed

• Work around (probable) AMD OpenCL compiler bug for
  reduce_by_index operations with complex operators that require
  locking.

• Properly handle another ICE on parse errors in test stanzas (#819).

• futhark_context_new_with_command_queue() now actually works. Oops.

• Different scopes are now properly addressed during type inference
  (#838). Realistically, there will still be some missing cases.

0.13.2

Added

• New subcommand, futhark query, for looking up information about
  the name at some position in a file. Intended for editor
  integration.

• (Finally) automatic support for compute model 7.5 in the CUDA backend.

• Somewhat better performance for very large target arrays for
  reduce_by_index..

Fixed

• Fixed a slice-iota simplification bug (#813).

• Fixed defunctionalisation crash involving intrinsics (#814).

0.13.1

Added

• Stack traces are now multiline for better legibility.

Changed

• The empty(t) notation now specifies the type of the entire
  value (not just the element type), and requires dimension sizes
  when t is an array (e.g. empty(i32) is no longer allowed, you
  need for example empty([0]i32)).

• All input files are now assumed to be in UTF-8.

Fixed

• Fixed exponential-time behaviour for certain kernels with large
  arithmetic expressions (#805).

• futhark test and friends no longer crash when reporting some
  errors (#808).

• Fix uniqueness of loop results (#810).