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Semantics of bulk memory operations

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#225 5 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
25/100
Issue type
Feature
Clarity
Needs clarification
Activity status
Stale
Tech stack
wasm
Domain
compilers

Research direction

Start by reviewing the issue's discussion of bulk memory operations on shared linear memory, the JavaScript memory-model comparison, and V8's use of C memmove and memcpy. Done means the semantics are specified clearly and the safety of the referenced implementation is resolved.

Written by the indexing model from the issue text.

Description

The semantics of bulk memory operations on shared linear memory seems to be currently underspecified. If the memory model is mostly the same as JS's, I assume these should be unordered atomic.

AFAICT V8's current implementation is also unsafe in that it just calls out to C memmove and memcpy under the hood, which are non-atomic.

@conrad-watt should know best.

Dominant language
WebAssembly
Stars
767
Forks
54
PR merge metrics
No merged PRs in 30d

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  4. Open a pull request that references the issue number.

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