specialize slice::fill to use memset when possible #147457
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RalfJung
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LLVM generally can do this on its own, but it helps miri and other backends.
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LGTM, r=me if you want but I'm not a libs reviewer. |
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(Removing extra @ from approved-by) @bors r=RalfJung,joboet |
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…Jung,joboet specialize slice::fill to use memset when possible It helps const eval performance rust-lang/miri#4616, debug builds and the gcc backend. Previously attempted in rust-lang#83245 but reverted due to unsoundness rust-lang#87891 around potentially-uninitialized types. This PR only handles primitives where the problem does not arise. split off from rust-lang#147294
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Rollup of 7 pull requests Successful merges: - #146568 (Port the implemention of SIMD intrinsics from Miri to const-eval) - #147373 (give a better example why `std` modules named like primitives are needed) - #147419 (bootstrap: add `Builder::rustc_cmd` that includes the lib path) - #147457 (specialize slice::fill to use memset when possible) - #147468 (Implement fs api set_times and set_times_nofollow) - #147489 (Prefer to use repeat_n over repeat().take()) - #147506 (compiletest: Isolate public APIs and minimize public surface area) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup of 12 pull requests Successful merges: - #146568 (Port the implemention of SIMD intrinsics from Miri to const-eval) - #147373 (give a better example why `std` modules named like primitives are needed) - #147419 (bootstrap: add `Builder::rustc_cmd` that includes the lib path) - #147420 (Add diagnostic items for `pub mod consts` of FP types) - #147457 (specialize slice::fill to use memset when possible) - #147467 (Fix double warnings on `#[no_mangle]`) - #147470 (Clarify how to remediate the panic_immediate_abort error) - #147480 (Do not invalidate CFG caches in CtfeLimit.) - #147481 (format: some small cleanup) - #147488 (refactor: Remove `LLVMRustInsertPrivateGlobal` and `define_private_global`) - #147489 (Prefer to use repeat_n over repeat().take()) - #147506 (compiletest: Isolate public APIs and minimize public surface area) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of #147457 - the8472:slice_fill_memset2, r=RalfJung,joboet specialize slice::fill to use memset when possible It helps const eval performance rust-lang/miri#4616, debug builds and the gcc backend. Previously attempted in #83245 but reverted due to unsoundness #87891 around potentially-uninitialized types. This PR only handles primitives where the problem does not arise. split off from #147294
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It helps const eval performance rust-lang/miri#4616, debug builds and the gcc backend.
Previously attempted in #83245 but reverted due to unsoundness #87891 around potentially-uninitialized types. This PR only handles primitives where the problem does not arise.
split off from #147294