Tag pointers, not scalars #217
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to make life easier for arithmetic on Word8/Word16 (#216) (This is with GC disabled.)
ggreif
approved these changes
Mar 6, 2019
Some of the tests in |
Co-Authored-By: nomeata <[email protected]>
9 tasks
and improve comments a bit.
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Hm, why do you need to shift pointers? Usually, pointer tagging just sets the LSB to 1 by exploiting the invariant that all pointers are aligned, so the lower bits carry no information. |
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The wording “shift“ is unfortunate, and we avoid it in the code actually: A pointer to position |
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Ah, okay, thanks for the clarification. Why not simply call it "tagged"? |
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Maybe to avoid confusion with the tagged heap objects? |
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which is somewhat hairy to implement (one has to mentally keep track what are actual pointers, and what are shifted pointers), but maybe as we work on the code over time some good practices will emerge.