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Support unaligned GC array accesses in `Prim`

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#409 8 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Stale
Tech stack
haskell
Domain
compilers

Research direction

Start by inspecting the existing Prim class APIs for array accesses and the GHC-provided read/write/indexWord8ArrayAs[ty]# primops described in the issue. Determine the corresponding exposed operations and verify them with the project’s existing tests; the work is done when safe unaligned GC array access is available through Prim without addressing the separate Addr# primops planned for GHC 9.10.

Written by the indexing model from the issue text.

Description

GHC exposes a set of (read|write|index)Word8ArrayAs[ty]# primops for safe unaligned accesses to GC pointers. I think the Prim class could sensibly expose these.

Also note that similar primops for Addr# non-GC pointers will be coming in GHC 9.10 .

Dominant language
Haskell
Stars
123
Forks
60
Avg merge
14d 14h
Merged PRs (30d)
1

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First steps

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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

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