alloc: consider the iterator size hint on every resize in extend_desugared#3
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alloc: consider the iterator size hint on every resize in extend_desugared#3joboet wants to merge 2 commits into
extend_desugared#3joboet wants to merge 2 commits into
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Because LLVM is unable to optimize well external iteration with some iterator kinds (e.g. `chain()`). To do that I had to hoist the `size_hint()` call to the beginning of the loop (since I no longer have access to the iterator inside the loop), which might slightly pessimize certain iterators that are able to give more accurate size bounds during iteration (e.g. `flatten()`). However, the effect should not be big, and also, common iterators like these also suffer from the external iteration optimizibility problem (e.g. `flatten()`).
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…r=jieyouxu Rehome 30 `tests/ui/issues/` tests to other subdirectories under `tests/ui/` [#3 of Batch #2] Part of rust-lang#133895 Methodology: 1. Refer to the previously written `tests/ui/SUMMARY.md` 2. Find an appropriate category for the test, using the original issue thread and the test contents. 3. Add the issue URL at the bottom (not at the top, as that would mess up stderr line numbers) 4. Rename the tests to make their purpose clearer Inspired by the methodology that `@Kivooeo` was using. r? `@jieyouxu`
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This restores the previous resize behaviour.