Allow aliasing between read-only buffers #12204
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Motivation: Aliasing is only a problem when mutation is involved. Since making a buffer read-only is irreversible, we can permit them to share the underlying memory. Modification: Add a `Buffer.copy` method that takes an argument for whether the resulting buffer should be read-only or not. If both original and copy buffers are read-only, then reuse the existing structural sharing mechanics of the const buffers, to make both read-only buffers share the same underlying memory. Result: Copying read-only buffers can now offer a useful optimisation.
normanmaurer
approved these changes
Mar 22, 2022
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Motivation:
Aliasing is only a problem when mutation is involved.
Since making a buffer read-only is irreversible, we can permit them to share the underlying memory.
Modification:
Add a
Buffer.copymethod that takes an argument for whether the resulting buffer should be read-only or not.If both original and copy buffers are read-only, then reuse the existing structural sharing mechanics of the const buffers, to make both read-only buffers share the same underlying memory.
Result:
Copying read-only buffers can now offer a useful optimisation.