Optimize ptr::replace
#122601
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Optimize ptr::replace
#122601
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rustbot has assigned @workingjubilee. Use r? to explicitly pick a reviewer |
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@joboet Do you expect running perf to be useful? |
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I don't really think so, most places will use |
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Yeah, that's what I expect too. @bors r+ |
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Rollup of 9 pull requests Successful merges: - rust-lang#117918 (Add `wasm_c_abi` `future-incompat` lint) - rust-lang#121545 (fix attribute validation on associated items in traits) - rust-lang#121720 (Split refining_impl_trait lint into _reachable, _internal variants) - rust-lang#122270 (fix `long-linker-command-lines` failure caused by `rust.rpath=false`) - rust-lang#122564 (Delegation: fix ICE on duplicated associative items) - rust-lang#122577 (Remove obsolete parameter `speculative` from `instantiate_poly_trait_ref`) - rust-lang#122601 (Optimize `ptr::replace`) - rust-lang#122604 (Mention jieyouxu for changes to compiletest, run-make tests and the run-make-support library) - rust-lang#122605 (rustc-metadata: Store crate name in self-profile of metadata_register_crate) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of rust-lang#122601 - joboet:ptr_replace, r=workingjubilee Optimize `ptr::replace` rust-lang#83022 optimized `mem::replace` to reduce the number of `memcpy`s. `ptr::replace`, which is [documented to behave just like `mem::replace`](https://doc.rust-lang.org/nightly/std/ptr/fn.replace.html), was not optimized however, leading to [worse code](https://godbolt.org/z/T3hdEEdfe) and missed optimizations. This PR simply forwards `ptr::replace` to `mem::replace` to take advantage of the better implementation.
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#83022 optimized
mem::replaceto reduce the number ofmemcpys.ptr::replace, which is documented to behave just likemem::replace, was not optimized however, leading to worse code and missed optimizations. This PR simply forwardsptr::replacetomem::replaceto take advantage of the better implementation.