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Fix wording on the aliasing section #366

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Jun 24, 2022
Merged

Fix wording on the aliasing section #366

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c192af3
Fix wording on the aliasing section
JohnTitor May 29, 2022
74faa41
Fix a typo on aliasing
JohnTitor May 29, 2022
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6 changes: 3 additions & 3 deletions src/aliasing.md
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Expand Up @@ -88,7 +88,7 @@ These optimizations also tend to prove the soundness of bigger optimizations
such as loop vectorization, constant propagation, and dead code elimination.

In the previous example, we used the fact that `&mut u32` can't be aliased to prove
that writes to `*output` can't possibly affect `*input`. This let us cache `*input`
that writes to `*output` can't possibly affect `*input`. This lets us cache `*input`
in a register, eliminating a read.

By caching this read, we knew that the write in the `> 10` branch couldn't
Expand Down Expand Up @@ -118,8 +118,8 @@ fn compute(input: &u32, output: &mut u32) {
}
```

We're still relying on alias analysis to assume that `temp` doesn't alias
`input`, but the proof is much simpler: the value of a local variable can't be
We're still relying on alias analysis to assume that `input` doesn't alias
`temp`, but the proof is much simpler: the value of a local variable can't be
aliased by things that existed before it was declared. This is an assumption
every language freely makes, and so this version of the function could be
optimized the way we want in any language.
Expand Down