Add SmallArray# type
Add a SmallArray# (and SmallMutableArray#) type that doesn't have a card table. This would
- save some memory (two words per array),
- make updates cheaper (no writing to the card table), and
- make GC faster (no traversing the card table).
The use case is the unordered-containers package, which uses small arrays to implement a hash array mapped trie.
A starting point would be [changeset:0417404f/ghc], which added the card table to the current array type.
Trac metadata
| Trac field | Value |
|---|---|
| Version | 7.9 |
| Type | FeatureRequest |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Compiler |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | |
| Architecture |
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