Add support for Apple Silicon #54
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And add FIXMEs for things that might also need updates.
legacy/reap/regionheap.h
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| class LeaHeap2 : | ||
| public | ||
| Threshold<4096, | ||
| Threshold<4096, // FIXME: is this page-size dependent? |
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@bpowers there were a couple of parts where I wasn't sure if the number was referring to the page size or another value, like here and below. I'm guessing this one should be changed to the page size (though not sure about the others), but do you know for sure?
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This particular heap layer is legacy code; I'm not sure it's being used by anyone. IIRC the size here was chosen arbitrarily (by me) but it might make sense to parameterize it by the system page size.
| // macOS on Apple Silicon aligns 16K pages to a 16K boundary. | ||
| // FIXME: is this the correct alignment? | ||
| enum { Size = 16 * 1024UL }; | ||
| enum { Alignment = 16 * 1024UL }; |
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I wasn't able to find any documentation about the alignment for Apple Silicon pages. I'm assuming they're 16K aligned?
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I believe this is correct. I'm not sure if vm_page_size is constexpr but if so, we could use that instead of hardcoding the numbers. Anyway, probably should also put in an assertion (if one is not there already) in the call to mmap to verify alignment and size.
| // macOS on Apple Silicon aligns 16K pages to a 16K boundary. | ||
| // FIXME: is this the correct alignment? | ||
| enum { Size = 16 * 1024UL }; | ||
| enum { Alignment = 16 * 1024UL }; |
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I believe this is correct. I'm not sure if vm_page_size is constexpr but if so, we could use that instead of hardcoding the numbers. Anyway, probably should also put in an assertion (if one is not there already) in the call to mmap to verify alignment and size.
legacy/reap/regionheap.h
Outdated
| class LeaHeap2 : | ||
| public | ||
| Threshold<4096, | ||
| Threshold<4096, // FIXME: is this page-size dependent? |
There was a problem hiding this comment.
This particular heap layer is legacy code; I'm not sure it's being used by anyone. IIRC the size here was chosen arbitrarily (by me) but it might make sense to parameterize it by the system page size.
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This is part of adding Apple Silicon support to Mesh.