fix: grow memory when necessary in BaseVec::set.#222
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## Problem `BaseVec`, which is the underlying data structure used by `StableVec` and `StableMinHeap` provides a `set` method that allows the caller to change the value of an element at a specified index. The `set` method used the `memory.write` method, which assumed that there is always enough memory to rewrite the element. This assumption would've been fine if other methods like `push` always allocated the maximum amount of space for every element. Currently though, `push` only allocates the amount needed to store the element that's being pushed. ## Solution There are two possible solutions: 1) Modify `push` to always allocate the maximum size of an element. 2) Modify `set` to grow the memory as needed as it's rewriting an element. This commit implements solution #2, which was both simpler and more performant.
ielashi
commented
Jun 7, 2024
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dsarlis
approved these changes
Jun 7, 2024
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Problem
BaseVec, which is the underlying data structure used byStableVecandStableMinHeapprovides asetmethod that allows the caller to change the value of an element at a specified index.The
setmethod used thememory.writemethod, which assumed that there is always enough memory to rewrite the element. This assumption would've been fine if other methods likepushalways allocated the maximum amount of space for every element. Currently though,pushonly allocates the amount needed to store the element that's being pushed.Solution
There are two possible solutions:
pushto always allocate the maximum size of an element.setto grow the memory as needed as it's rewriting an element.This commit implements solution 2, which is both simpler and more performant.