Minutes_2018_05_17

Numba Meeting: 2018-05-17

Attendees: Ehsan, Todd, Siu, Stuart, Stan

1. New issues

• #2972: [Feature Request] Support array.conj()
  • Easy fix
• #2971: Recursive function with optional types
  • Siu will take a look
• #2965: CUDA target needs error message overhaul similar to CPU
  • Makes it hard to interpret errors
• #2964: @{gu,}vectorize docs should mention promotion/dispatch behaviours.
  • Need to do until we replace guvectorize
  • Easy to add
• #2962: numba.errors.LoweringError: Failed at object (object mode frontend)
  • A lot of unsupported features. Lambda with conditional in use.
• #2961: Generators within @jitclass that yield vectors produce segmentation faults bug
  • Siu will take a look
• #2960: Feature request: optimize permutable nested prange
  • Not possible to solve in general
  • Polyhedral analysis in LLVM help?
  • prange makes this extra hard
  • We should document the nested prange behavior
  • Suggest VTune as an option for advanced analysis
• #2958: Device function declaration order error message
  • take out the type annotations to allow defered compilation
  • Need FAQ on why not to use explicit type annotations
  • Siu will reply
• #2956: Passing a jitted function reference to a jitted function makes cache=True fail
  • Can this limitation be lifted?
  • caching in general has issues with pointers to other things
  • Siu will think about this
• #2955: "AssertionError: Failed at object (object mode frontend)" exception from simple code
  • Need to put things back if compiler pipeline fails

2. Open PRs

New

• #2968 WIP: Adding xnd kernels
  • Siu giving author feedback on approach
  • This might work for ragged arrays now??
• #2963 Improve alias analysis to be more comprehensive
  • Ehsan will update tests
• #2959 np.unique return_counts support
  • Doesn't work as is
  • Provided feedback on how to fix
• #2957 Add new 3.7 opcode support.
  • Not being automatically tested yet since we need llvmlite for Python 3.7
  • Stuart will add object mode test that produces these opcodes

Old

• #2953 percentile and nanpercentile
  • reviewed, waiting on author fixes
• #2950 Fix dispatcher to only consider contiguous-ness.
  • Stuart to talk to Siu about read-only array case
• #2942 Fix linkage nature (declspec(dllexport)) of some test functions
  • Should maybe generalize this to cover other places
• #2939 comprehensive SVML test
  • Stuart will fix with autopep8 and merge it
• #2930 Add configuration file and color schemes.
  • Merged
• #2929 Add Flag To Prevent Unneccessary D->H Copies
  • Need to implement decorator to show user how to solve their problem without putting a global default copy strategy into code
• #2928 [WIP] Making error about untyped list more informative.
  • Check with Siu as to whether this is ready to review
• #2910: [WIP] More CUDA intrinsics
  • Check if it works on GPU
  • Make sure it goes thru the buildfarm before merging
  • Blocked on how to simulate in CUDA simulator. See recent njwhite patches?
• #2905: Fix for #2862
  • need to replicate old incorrect behavior in NumPy <= 1.11
• #2897: [WIP] Fix line position of delete statement in numba ir
  • Stuart will review
• #2894: [WIP] Implement jitclass default constructor arguments.
  • Need to give some feedback to contributor on approach
• #2869: WIP: use pairwise summation in sum
  • Producing wrong results in some cases
  • Open new PR with Stuart's non-recursive implementation
• #2860: __cuda_array_interface__
  • Two small doc fixes, and then ready to merge
  • Stan will merge
• #2840: Support list of refcounted types
  • Problems found in review that need to be fixed
  • Siu will take a look
• #2817: [WIP] Emit LLVM optimization remarks
  • Want to refactor to not require temp file on disk
• #2793: Simplify and remove javascript from html_annotate templates.
  • Need to push some refactoring onto the PR

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3. Feature Discussion

• Numba in Anaconda defaults channel status

  • tag llvmlite 0.23.1
  • ask distro team to build

• Preparing for Python 3.7

  • _

• Stuart to add an issue full of things about Parfors that seem to be common questions with view of turning this into a FAQ.

• Add PEP8 testing in CI for PR?

4. Next Release: Version 0.39, RC=June 18, 2018, Final=June 25, 2018

• Python 3.7 support
• ARM fixes
• Reference-counted items (arrays lists) in lists
• Python mode blocks in nopython mode
• HTML annotation improvements