compiler: Don't mark SingleUseConsts MIR pass as "required for soundness"#152729
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Some changes occurred to MIR optimizations cc @rust-lang/wg-mir-opt |
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…dness" Because: * Something like it did not exist before PR 107404 * That it is not run our mir-opt-level 0 indicates that it is not required for soundness * Its `MirPass::can_be_overridden()` is unchanged and thus returns true, indicating that it is not a required MIR pass. * No test fails in PR 151426 that stops enabling by default in non-optimized builds As can be seen from the updated test `tests/mir-opt/optimize_none.rs`, this means that `#[optimize(none)]` functions become even less optimized. As expected and as desired.
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…ired, r=cjgillot compiler: Don't mark `SingleUseConsts` MIR pass as "required for soundness" I don't think this MIR pass is required for soundness. The reasons are: * Something like it was not enabled by default before PR rust-lang#107404 which was the precursor to `SingleUseConsts` (see rust-lang#125910 for the switch). * By following the advice from rust-lang#128657 (comment) we can conclude it is not required for soundness since it has only ever run on MIR opt level > 0. * Its [`MirPass::can_be_overridden()`](https://github.com/rust-lang/rust/blob/0ee7d96253f92b15115c94a530db8b79cb341b15/compiler/rustc_mir_transform/src/pass_manager.rs#L98-L102) is unchanged and thus returns `true`, indicating that it is not a required MIR pass. * PR CI pass in rust-lang#151426 which stops enabling it by default in non-optimized builds. As shown in the updated test `tests/mir-opt/optimize_none.rs`, `#[optimize(none)]` functions become even less optimized, as expected and desired. Unblocks rust-lang#151426.
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…ired, r=cjgillot compiler: Don't mark `SingleUseConsts` MIR pass as "required for soundness" I don't think this MIR pass is required for soundness. The reasons are: * Something like it was not enabled by default before PR rust-lang#107404 which was the precursor to `SingleUseConsts` (see rust-lang#125910 for the switch). * By following the advice from rust-lang#128657 (comment) we can conclude it is not required for soundness since it has only ever run on MIR opt level > 0. * Its [`MirPass::can_be_overridden()`](https://github.com/rust-lang/rust/blob/0ee7d96253f92b15115c94a530db8b79cb341b15/compiler/rustc_mir_transform/src/pass_manager.rs#L98-L102) is unchanged and thus returns `true`, indicating that it is not a required MIR pass. * PR CI pass in rust-lang#151426 which stops enabling it by default in non-optimized builds. As shown in the updated test `tests/mir-opt/optimize_none.rs`, `#[optimize(none)]` functions become even less optimized, as expected and desired. Unblocks rust-lang#151426.
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…ired, r=cjgillot compiler: Don't mark `SingleUseConsts` MIR pass as "required for soundness" I don't think this MIR pass is required for soundness. The reasons are: * Something like it was not enabled by default before PR rust-lang#107404 which was the precursor to `SingleUseConsts` (see rust-lang#125910 for the switch). * By following the advice from rust-lang#128657 (comment) we can conclude it is not required for soundness since it has only ever run on MIR opt level > 0. * Its [`MirPass::can_be_overridden()`](https://github.com/rust-lang/rust/blob/0ee7d96253f92b15115c94a530db8b79cb341b15/compiler/rustc_mir_transform/src/pass_manager.rs#L98-L102) is unchanged and thus returns `true`, indicating that it is not a required MIR pass. * PR CI pass in rust-lang#151426 which stops enabling it by default in non-optimized builds. As shown in the updated test `tests/mir-opt/optimize_none.rs`, `#[optimize(none)]` functions become even less optimized, as expected and desired. Unblocks rust-lang#151426.
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Rollup of 19 pull requests Successful merges: - #145399 (Unify wording of resolve error) - #150473 (tail calls: fix copying non-scalar arguments to callee) - #152637 (Add a note about elided lifetime) - #152657 (std: move `exit` out of PAL) - #152729 (compiler: Don't mark `SingleUseConsts` MIR pass as "required for soundness") - #152753 (remove the explicit error for old `rental` versions) - #152758 (Remove ShallowInitBox.) - #151530 (Fix invalid `mut T` suggestion for `&mut T` in missing lifetime error) - #152179 (Add documentation note about signed overflow direction) - #152474 (Implement opt-bisect-limit for MIR) - #152509 (tests/ui/test-attrs: add annotations for reference rules) - #152672 (std: use libc version of `_NSGetArgc`/`_NSGetArgv`) - #152711 (resolve: Disable an assert that no longer holds) - #152732 (add regression test for 147958) - #152745 (Fix ICE in `suggest_param_env_shadowing` with incompatible args) - #152749 (make `rustc_allow_const_fn_unstable` an actual `rustc_attrs` attribute) - #152756 (Miri: recursive validity: also recurse into Boxes) - #152770 (carryless_mul: mention the base) - #152778 (Update tracking issue number for final_associated_functions)
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Rollup of 20 pull requests Successful merges: - #145399 (Unify wording of resolve error) - #150473 (tail calls: fix copying non-scalar arguments to callee) - #152637 (Add a note about elided lifetime) - #152729 (compiler: Don't mark `SingleUseConsts` MIR pass as "required for soundness") - #152751 (Rename dep node "fingerprints" to distinguish key and value hashes) - #152753 (remove the explicit error for old `rental` versions) - #152758 (Remove ShallowInitBox.) - #151530 (Fix invalid `mut T` suggestion for `&mut T` in missing lifetime error) - #152179 (Add documentation note about signed overflow direction) - #152474 (Implement opt-bisect-limit for MIR) - #152509 (tests/ui/test-attrs: add annotations for reference rules) - #152672 (std: use libc version of `_NSGetArgc`/`_NSGetArgv`) - #152711 (resolve: Disable an assert that no longer holds) - #152725 (Rework explanation of CLI lint level flags) - #152732 (add regression test for 147958) - #152745 (Fix ICE in `suggest_param_env_shadowing` with incompatible args) - #152749 (make `rustc_allow_const_fn_unstable` an actual `rustc_attrs` attribute) - #152756 (Miri: recursive validity: also recurse into Boxes) - #152770 (carryless_mul: mention the base) - #152778 (Update tracking issue number for final_associated_functions)
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Rollup merge of #152729 - Enselic:single_use_consts-not-required, r=cjgillot compiler: Don't mark `SingleUseConsts` MIR pass as "required for soundness" I don't think this MIR pass is required for soundness. The reasons are: * Something like it was not enabled by default before PR #107404 which was the precursor to `SingleUseConsts` (see #125910 for the switch). * By following the advice from #128657 (comment) we can conclude it is not required for soundness since it has only ever run on MIR opt level > 0. * Its [`MirPass::can_be_overridden()`](https://github.com/rust-lang/rust/blob/0ee7d96253f92b15115c94a530db8b79cb341b15/compiler/rustc_mir_transform/src/pass_manager.rs#L98-L102) is unchanged and thus returns `true`, indicating that it is not a required MIR pass. * PR CI pass in #151426 which stops enabling it by default in non-optimized builds. As shown in the updated test `tests/mir-opt/optimize_none.rs`, `#[optimize(none)]` functions become even less optimized, as expected and desired. Unblocks #151426.
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I don't think this MIR pass is required for soundness. The reasons are:
SingleUseConsts(see AddSingleUseConstsmir-opt pass #125910 for the switch).#[optimize(none)]#128657 (comment) we can conclude it is not required for soundness since it has only ever run on MIR opt level > 0.MirPass::can_be_overridden()is unchanged and thus returnstrue, indicating that it is not a required MIR pass.mir_opt_level > 1forSingleUseConstsMIR pass #151426 which stops enabling it by default in non-optimized builds.As shown in the updated test
tests/mir-opt/optimize_none.rs,#[optimize(none)]functions become even less optimized, as expected and desired.Unblocks #151426.