Small shared n-way pointer #4654
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src/util/small_shared_n_way_ptr.h
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| Num use_count() const |
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Could we actually name this get_use_count to avoid the final underscore in use_count_? It would also seem a lot more consistent, because we have increment_use_count and decrement_use_count.
src/util/small_shared_n_way_ptr.h
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| void increment_use_count() | ||
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| PRECONDITION((use_count_ & use_count_mask) < use_count_mask); |
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Nit pick: use get_use_count()
src/util/small_shared_n_way_ptr.h
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| void decrement_use_count() | ||
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| PRECONDITION((use_count_ & use_count_mask) > 0); |
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Nit pick: use get_use_count()
src/util/small_shared_n_way_ptr.h
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| { | ||
| PRECONDITION((use_count_ & use_count_mask) < use_count_mask); | ||
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| use_count_++; |
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Nit pick: use pre-increment rather than having the compiler figure this out.
src/util/small_shared_n_way_ptr.h
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| { | ||
| PRECONDITION((use_count_ & use_count_mask) > 0); | ||
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| use_count_--; |
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Nit pick: use pre-decrement rather than making the compiler figure this out.
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This replaces small_shared_two_way_ptrt with small_shared_n_way_ptrt. The new shared pointer type allows more than two types for the managed objects. This can be useful e.g. for implementing graph data structures with sharing where there are more than two different node types.
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Passed Diffblue compatibility checks (cbmc commit: 922adf0).
Build URL: https://travis-ci.com/diffblue/test-gen/builds/111896232
This replaces
small_shared_two_way_ptrtwithsmall_shared_n_way_ptrt. The new shared pointer type allows more than two types for the managed objects. This can be useful e.g. for implementing graph data structures with sharing where there are more than two different node types.This is in preparation for a sharing map improvement where a further node type will be introduced for leaf nodes that are not at the bottom of the tree (which will be possible once the variable-height tree PR #4641 has been merged).