0.18.3

Fixed

• Python backend now disables spurious NumPy overflow warnings for
  both library and binary code (#1180).

• Undid deadlocking over-synchronisation for freeing opaque objects.

• futhark datacmp now handles bad input files better (#1181).

0.18.2

Added

• The GPU loop tiler can now handle loops where only a subset of the
  input arrays are tiled. Matrix-vector multiplication is one
  important program where this helps (#1145).

• The number of threads used by the multicore backend is now
  configurable (--num-threads and
  futhark_context_config_set_num_threads()). (#1162)

Fixed

• PyOpenCL backend would mistakenly still streat entry point
  argument sizes as 32 bit.

• Warnings are now reported even for programs with type errors.

• Multicore backend now works properly for very large iteration
  spaces.

• A few internal generated functions (init_constants(),
  free_constants()) were mistakenly declared non-static.

• Process exit code is now nonzero when compiler bugs and
  limitations are encountered.

• Multicore backend crashed on reduce_by_index with nonempty target
  and empty input.

• Fixed a flattening issue for certain complex map nestings
  (#1168).

• Made API function futhark_context_clear_caches() thread safe
  (#1169).

• API functions for freeing opaque objects are now thread-safe
  (#1169).

• Tools such as futhark dataset no longer crash with an internal
  error if writing to a broken pipe (but they will return a nonzero
  exit code).

• Defunctionalisation had a name shadowing issue that would crop up
  for programs making very advanced use of functional
  representations (#1174).

• Type checker erroneously permitted pattern-matching on string
  literals (this would fail later in the compiler).

• New coverage checker for pattern matching, which is more correct.
  However, it may not provide quite as nice counter-examples
  (#1134).

• Fix rare internalisation error (#1177).

0.16.5

Fixed

• Made API function futhark_context_clear_caches() thread safe
  (#1169).

• API functions for freeing opaque objects are now thread-safe
  (#1169).

0.18.1

Added

• Experimental multi-threaded CPU backend, multicore.

Changed

• All sizes are now of type i64. This has wide-ranging
  implications and most programs will need to be updated (#134).

0.17.3

Added

• Improved parallelisation of futhark bench compilation.

Fixed

• Dataset generation for test programs now use the right futhark
  executable (#1133).

• Really fix NaN comparisons in interpreter (#1070, again).

• Fix entry points with a parameter that is a sum type where
  multiple constructors contain arrays of the same statically known
  size.

• Fix in monomorphisation of types with constant sizes.

• Fix in in-place lowering (#1142).

• Fix tiling inside multiple nested loops (#1143).

0.17.2

Added

• Obscure loop optimisation (#1110).

• Faster matrix transposition in C backend.

• Library code generated with CUDA backend can now be called from
  multiple threads.

• Better optimisation of concatenations of array literals and
  replicates.

• Array creation C API functions now accept const pointers.

• Arrays can now be indexed (but not sliced) with any signed integer
  type (#1122).

• Added --list-devices command to OpenCL binaries (#1131)

• Added --help command to C, CUDA and OpenCL binaries (#1131)

Removed

• The integer modules no longer contain iota and replicate
  functions. The top-level ones still exist.

• The size module type has been removed from the prelude.

Changed

• Range literals may no longer be produced from unsigned integers.

Fixed

• Entry points with names that are not valid C (or Python)
  identifiers are now pointed out as problematic, rather than
  generating invalid C code.

• Exotic tiling bug (#1112).

• Missing synchronisation for in-place updates at group level.

• Fixed (in a hacky way) an issue where reduce_by_index would use
  too much local memory on AMD GPUs when using the OpenCL backend.

0.16.4

Added

• #[unroll] attribute.

• Better error message when writing a[i][j] (#1095).

• Better error message when missing "in" (#1091).

Fixed

• Fixed compiler crash on certain patterns of nested parallelism
  (#1068, #1069).

• NaN comparisons are now done properly in interpreter (#1070).

• Fix incorrect movement of array indexing into branches ifs
  (#1073).

• Fix defunctorisation bug (#1088).

• Fix issue where loop tiling might generate out-of-bounds reads
  (#1094).

• Scans of empty arrays no longer result in out-of-bounds memory
  reads.

• Fix yet another defunctionalisation bug due to missing
  eta-expansion (#1100).

0.16.3

Added

• random input blocks for futhark test and futhark bench now
  support floating-point literals, which must always have either an
  f32 or f64 suffix.

• The cuda backend now supports the -d option for executables.

• The integer modules now contain a ctz function for counting
  trailing zeroes.

Fixed

• The pyopencl backend now works with OpenCL devices that have
  multiple types (most importantly, oclgrind).

• Fix barrier divergence when generating code for group-level
  colletive copies in GPU backend.

• Intra-group flattening now looks properly inside of branches.

• Intra-group flattened code versions are no longer used when the
  resulting workgroups would have less than 32 threads (with default
  thresholds anyway) (#1064).

0.16.2

Added

• futhark autotune: added --pass-option.

Fixed

• futhark bench: progress bar now correct when number of runs is
  less than 10 (#1050).

• Aliases of arguments passed for consuming parameters are now
  properly checked (#1053).

• When using a GPU backend, errors are now properly cleared.
  Previously, once e.g. an out-of-bounds error had occurred, all
  future operations would fail with the same error.

• Size-coercing a transposed array no longer leads to invalid code
  generation (#1054).

0.16.1

Added

• Incremental flattening is now performed by default. Use
  attributes to constrain and direct the flattening if you have
  exotic needs. This will likely need further iteration and
  refinement.

• Better code generation for reverse (and the equivalent explicit
  slice).

• futhark bench now prints progress bars.

• The cuda backend now supports similar profiling as the opencl
  option, although it is likely slightly less accurate in the
  presence of concurrent operations.

• A preprocessor macro FUTHARK_BACKEND_foo is now defined in
  generated header files, where foo is the name of the backend
  used.

• Non-inlined functions (via #[noinline]) are now supported in GPU
  code, but only for functions that exclusively operate on
  scalars.

• futhark repl now accepts a command line argument to load a
  program initially.

• Attributes are now also permitted on declarations and specs.

• futhark repl now has a :nanbreak command (#839).

Removed

• The C# backend has been removed (#984).

• The unsafe keyword has been removed. Use #[unsafe] instead.

Changed

• Out-of-bounds literals are now an error rather than a warning.

• Type ascriptions on entry points now always result in opaque types
  when the underlying concrete type is a tuple (#1048).

Fixed

• Fix bug in slice simplification (#992).

• Fixed a typer checker bug for tracking the aliases of closures
  (#995).

• Fixed handling of dumb terminals in futhark test (#1000).

• Fixed exotic monomorphisation case involving lifted type
  parameters instantiated with functions that take named parameters
  (#1026).

• Further tightening of the causality restriction (#1042).

• Fixed alias tracking for right-operand operator sections (#1043).