diff options
Diffstat (limited to 'compiler')
19 files changed, 343 insertions, 245 deletions
diff --git a/compiler/rustc_codegen_gcc/src/type_of.rs b/compiler/rustc_codegen_gcc/src/type_of.rs index 183e9ddf8bf..db874afe1ab 100644 --- a/compiler/rustc_codegen_gcc/src/type_of.rs +++ b/compiler/rustc_codegen_gcc/src/type_of.rs @@ -197,7 +197,7 @@ impl<'tcx> LayoutGccExt<'tcx> for TyAndLayout<'tcx> { /// `[T]` becomes `T`, while `str` and `Trait` turn into `i8` - this /// is useful for indexing slices, as `&[T]`'s data pointer is `T*`. /// If the type is an unsized struct, the regular layout is generated, - /// with the inner-most trailing unsized field using the "minimal unit" + /// with the innermost trailing unsized field using the "minimal unit" /// of that field's type - this is useful for taking the address of /// that field and ensuring the struct has the right alignment. fn gcc_type<'gcc>(&self, cx: &CodegenCx<'gcc, 'tcx>) -> Type<'gcc> { diff --git a/compiler/rustc_codegen_llvm/src/type_of.rs b/compiler/rustc_codegen_llvm/src/type_of.rs index 1af666f818b..6be4c3f034f 100644 --- a/compiler/rustc_codegen_llvm/src/type_of.rs +++ b/compiler/rustc_codegen_llvm/src/type_of.rs @@ -191,7 +191,7 @@ impl<'tcx> LayoutLlvmExt<'tcx> for TyAndLayout<'tcx> { /// `[T]` becomes `T`, while `str` and `Trait` turn into `i8` - this /// is useful for indexing slices, as `&[T]`'s data pointer is `T*`. /// If the type is an unsized struct, the regular layout is generated, - /// with the inner-most trailing unsized field using the "minimal unit" + /// with the innermost trailing unsized field using the "minimal unit" /// of that field's type - this is useful for taking the address of /// that field and ensuring the struct has the right alignment. fn llvm_type<'a>(&self, cx: &CodegenCx<'a, 'tcx>) -> &'a Type { diff --git a/compiler/rustc_codegen_ssa/src/base.rs b/compiler/rustc_codegen_ssa/src/base.rs index f3d9a7d37e6..a726ee73aaa 100644 --- a/compiler/rustc_codegen_ssa/src/base.rs +++ b/compiler/rustc_codegen_ssa/src/base.rs @@ -888,7 +888,7 @@ impl CrateInfo { // below. // // In order to get this left-to-right dependency ordering, we use the reverse - // postorder of all crates putting the leaves at the right-most positions. + // postorder of all crates putting the leaves at the rightmost positions. let mut compiler_builtins = None; let mut used_crates: Vec<_> = tcx .postorder_cnums(()) diff --git a/compiler/rustc_errors/src/emitter.rs b/compiler/rustc_errors/src/emitter.rs index 1adb6b9dcfe..0ccc71ae06c 100644 --- a/compiler/rustc_errors/src/emitter.rs +++ b/compiler/rustc_errors/src/emitter.rs @@ -58,9 +58,9 @@ impl HumanReadableErrorType { struct Margin { /// The available whitespace in the left that can be consumed when centering. pub whitespace_left: usize, - /// The column of the beginning of left-most span. + /// The column of the beginning of leftmost span. pub span_left: usize, - /// The column of the end of right-most span. + /// The column of the end of rightmost span. pub span_right: usize, /// The beginning of the line to be displayed. pub computed_left: usize, @@ -128,7 +128,7 @@ impl Margin { } else { 0 }; - // We want to show as much as possible, max_line_len is the right-most boundary for the + // We want to show as much as possible, max_line_len is the rightmost boundary for the // relevant code. self.computed_right = max(max_line_len, self.computed_left); @@ -685,7 +685,7 @@ impl HumanEmitter { buffer.puts(line_offset, code_offset, "...", Style::LineNumber); } if margin.was_cut_right(line_len) { - // We have stripped some code after the right-most span end, make it clear we did so. + // We have stripped some code after the rightmost span end, make it clear we did so. buffer.puts(line_offset, code_offset + taken - 3, "...", Style::LineNumber); } buffer.puts(line_offset, 0, &self.maybe_anonymized(line_index), Style::LineNumber); diff --git a/compiler/rustc_expand/messages.ftl b/compiler/rustc_expand/messages.ftl index 57bac9d09d5..fcf3352bfc5 100644 --- a/compiler/rustc_expand/messages.ftl +++ b/compiler/rustc_expand/messages.ftl @@ -25,7 +25,7 @@ expand_collapse_debuginfo_illegal = illegal value for attribute #[collapse_debuginfo(no|external|yes)] expand_count_repetition_misplaced = - `count` can not be placed inside the inner-most repetition + `count` can not be placed inside the innermost repetition expand_crate_name_in_cfg_attr = `crate_name` within an `#![cfg_attr]` attribute is forbidden diff --git a/compiler/rustc_expand/src/mbe/metavar_expr.rs b/compiler/rustc_expand/src/mbe/metavar_expr.rs index c4ba98f581e..810a5d30c7e 100644 --- a/compiler/rustc_expand/src/mbe/metavar_expr.rs +++ b/compiler/rustc_expand/src/mbe/metavar_expr.rs @@ -23,11 +23,11 @@ pub(crate) enum MetaVarExpr { /// Ignore a meta-variable for repetition without expansion. Ignore(Ident), - /// The index of the repetition at a particular depth, where 0 is the inner-most + /// The index of the repetition at a particular depth, where 0 is the innermost /// repetition. The `usize` is the depth. Index(usize), - /// The length of the repetition at a particular depth, where 0 is the inner-most + /// The length of the repetition at a particular depth, where 0 is the innermost /// repetition. The `usize` is the depth. Len(usize), } diff --git a/compiler/rustc_expand/src/mbe/transcribe.rs b/compiler/rustc_expand/src/mbe/transcribe.rs index fb6fe0bb1d7..34811ca2b35 100644 --- a/compiler/rustc_expand/src/mbe/transcribe.rs +++ b/compiler/rustc_expand/src/mbe/transcribe.rs @@ -570,7 +570,7 @@ fn lockstep_iter_size( } } -/// Used solely by the `count` meta-variable expression, counts the outer-most repetitions at a +/// Used solely by the `count` meta-variable expression, counts the outermost repetitions at a /// given optional nested depth. /// /// For example, a macro parameter of `$( { $( $foo:ident ),* } )*` called with `{ a, b } { c }`: diff --git a/compiler/rustc_hir_analysis/src/check/compare_impl_item.rs b/compiler/rustc_hir_analysis/src/check/compare_impl_item.rs index 75956165e87..fc5ec31cda8 100644 --- a/compiler/rustc_hir_analysis/src/check/compare_impl_item.rs +++ b/compiler/rustc_hir_analysis/src/check/compare_impl_item.rs @@ -43,14 +43,13 @@ mod refine; /// - `impl_m`: type of the method we are checking /// - `trait_m`: the method in the trait /// - `impl_trait_ref`: the TraitRef corresponding to the trait implementation +#[instrument(level = "debug", skip(tcx))] pub(super) fn compare_impl_method<'tcx>( tcx: TyCtxt<'tcx>, impl_m: ty::AssocItem, trait_m: ty::AssocItem, impl_trait_ref: ty::TraitRef<'tcx>, ) { - debug!("compare_impl_method(impl_trait_ref={:?})", impl_trait_ref); - let _: Result<_, ErrorGuaranteed> = try { check_method_is_structurally_compatible(tcx, impl_m, trait_m, impl_trait_ref, false)?; compare_method_predicate_entailment(tcx, impl_m, trait_m, impl_trait_ref)?; @@ -167,8 +166,6 @@ fn compare_method_predicate_entailment<'tcx>( trait_m: ty::AssocItem, impl_trait_ref: ty::TraitRef<'tcx>, ) -> Result<(), ErrorGuaranteed> { - let trait_to_impl_args = impl_trait_ref.args; - // This node-id should be used for the `body_id` field on each // `ObligationCause` (and the `FnCtxt`). // @@ -183,27 +180,17 @@ fn compare_method_predicate_entailment<'tcx>( kind: impl_m.kind, }); - // Create mapping from impl to placeholder. - let impl_to_placeholder_args = GenericArgs::identity_for_item(tcx, impl_m.def_id); - - // Create mapping from trait to placeholder. - let trait_to_placeholder_args = - impl_to_placeholder_args.rebase_onto(tcx, impl_m.container_id(tcx), trait_to_impl_args); - debug!("compare_impl_method: trait_to_placeholder_args={:?}", trait_to_placeholder_args); + // Create mapping from trait method to impl method. + let trait_to_impl_args = GenericArgs::identity_for_item(tcx, impl_m.def_id).rebase_onto( + tcx, + impl_m.container_id(tcx), + impl_trait_ref.args, + ); + debug!(?trait_to_impl_args); let impl_m_predicates = tcx.predicates_of(impl_m.def_id); let trait_m_predicates = tcx.predicates_of(trait_m.def_id); - // Create obligations for each predicate declared by the impl - // definition in the context of the trait's parameter - // environment. We can't just use `impl_env.caller_bounds`, - // however, because we want to replace all late-bound regions with - // region variables. - let impl_predicates = tcx.predicates_of(impl_m_predicates.parent.unwrap()); - let mut hybrid_preds = impl_predicates.instantiate_identity(tcx); - - debug!("compare_impl_method: impl_bounds={:?}", hybrid_preds); - // This is the only tricky bit of the new way we check implementation methods // We need to build a set of predicates where only the method-level bounds // are from the trait and we assume all other bounds from the implementation @@ -211,25 +198,25 @@ fn compare_method_predicate_entailment<'tcx>( // // We then register the obligations from the impl_m and check to see // if all constraints hold. - hybrid_preds.predicates.extend( - trait_m_predicates - .instantiate_own(tcx, trait_to_placeholder_args) - .map(|(predicate, _)| predicate), + let impl_predicates = tcx.predicates_of(impl_m_predicates.parent.unwrap()); + let mut hybrid_preds = impl_predicates.instantiate_identity(tcx).predicates; + hybrid_preds.extend( + trait_m_predicates.instantiate_own(tcx, trait_to_impl_args).map(|(predicate, _)| predicate), ); - // Construct trait parameter environment and then shift it into the placeholder viewpoint. - // The key step here is to update the caller_bounds's predicates to be - // the new hybrid bounds we computed. let normalize_cause = traits::ObligationCause::misc(impl_m_span, impl_m_def_id); - let param_env = ty::ParamEnv::new(tcx.mk_clauses(&hybrid_preds.predicates), Reveal::UserFacing); + let param_env = ty::ParamEnv::new(tcx.mk_clauses(&hybrid_preds), Reveal::UserFacing); let param_env = traits::normalize_param_env_or_error(tcx, param_env, normalize_cause); + debug!(caller_bounds=?param_env.caller_bounds()); let infcx = &tcx.infer_ctxt().build(); let ocx = ObligationCtxt::new_with_diagnostics(infcx); - debug!("compare_impl_method: caller_bounds={:?}", param_env.caller_bounds()); - - let impl_m_own_bounds = impl_m_predicates.instantiate_own(tcx, impl_to_placeholder_args); + // Create obligations for each predicate declared by the impl + // definition in the context of the hybrid param-env. This makes + // sure that the impl's method's where clauses are not more + // restrictive than the trait's method (and the impl itself). + let impl_m_own_bounds = impl_m_predicates.instantiate_own_identity(); for (predicate, span) in impl_m_own_bounds { let normalize_cause = traits::ObligationCause::misc(span, impl_m_def_id); let predicate = ocx.normalize(&normalize_cause, param_env, predicate); @@ -256,7 +243,6 @@ fn compare_method_predicate_entailment<'tcx>( // any associated types appearing in the fn arguments or return // type. - // Compute placeholder form of impl and trait method tys. let mut wf_tys = FxIndexSet::default(); let unnormalized_impl_sig = infcx.instantiate_binder_with_fresh_vars( @@ -267,9 +253,9 @@ fn compare_method_predicate_entailment<'tcx>( let norm_cause = ObligationCause::misc(impl_m_span, impl_m_def_id); let impl_sig = ocx.normalize(&norm_cause, param_env, unnormalized_impl_sig); - debug!("compare_impl_method: impl_fty={:?}", impl_sig); + debug!(?impl_sig); - let trait_sig = tcx.fn_sig(trait_m.def_id).instantiate(tcx, trait_to_placeholder_args); + let trait_sig = tcx.fn_sig(trait_m.def_id).instantiate(tcx, trait_to_impl_args); let trait_sig = tcx.liberate_late_bound_regions(impl_m.def_id, trait_sig); // Next, add all inputs and output as well-formed tys. Importantly, @@ -280,9 +266,7 @@ fn compare_method_predicate_entailment<'tcx>( // We also have to add the normalized trait signature // as we don't normalize during implied bounds computation. wf_tys.extend(trait_sig.inputs_and_output.iter()); - let trait_fty = Ty::new_fn_ptr(tcx, ty::Binder::dummy(trait_sig)); - - debug!("compare_impl_method: trait_fty={:?}", trait_fty); + debug!(?trait_sig); // FIXME: We'd want to keep more accurate spans than "the method signature" when // processing the comparison between the trait and impl fn, but we sadly lose them @@ -455,8 +439,6 @@ pub(super) fn collect_return_position_impl_trait_in_trait_tys<'tcx>( // just so we don't ICE during instantiation later. check_method_is_structurally_compatible(tcx, impl_m, trait_m, impl_trait_ref, true)?; - let trait_to_impl_args = impl_trait_ref.args; - let impl_m_hir_id = tcx.local_def_id_to_hir_id(impl_m_def_id); let return_span = tcx.hir().fn_decl_by_hir_id(impl_m_hir_id).unwrap().output.span(); let cause = @@ -466,18 +448,18 @@ pub(super) fn collect_return_position_impl_trait_in_trait_tys<'tcx>( kind: impl_m.kind, }); - // Create mapping from impl to placeholder. - let impl_to_placeholder_args = GenericArgs::identity_for_item(tcx, impl_m.def_id); - - // Create mapping from trait to placeholder. - let trait_to_placeholder_args = - impl_to_placeholder_args.rebase_onto(tcx, impl_m.container_id(tcx), trait_to_impl_args); + // Create mapping from trait to impl (i.e. impl trait header + impl method identity args). + let trait_to_impl_args = GenericArgs::identity_for_item(tcx, impl_m.def_id).rebase_onto( + tcx, + impl_m.container_id(tcx), + impl_trait_ref.args, + ); let hybrid_preds = tcx .predicates_of(impl_m.container_id(tcx)) .instantiate_identity(tcx) .into_iter() - .chain(tcx.predicates_of(trait_m.def_id).instantiate_own(tcx, trait_to_placeholder_args)) + .chain(tcx.predicates_of(trait_m.def_id).instantiate_own(tcx, trait_to_impl_args)) .map(|(clause, _)| clause); let param_env = ty::ParamEnv::new(tcx.mk_clauses_from_iter(hybrid_preds), Reveal::UserFacing); let param_env = traits::normalize_param_env_or_error( @@ -511,7 +493,7 @@ pub(super) fn collect_return_position_impl_trait_in_trait_tys<'tcx>( .instantiate_binder_with_fresh_vars( return_span, infer::HigherRankedType, - tcx.fn_sig(trait_m.def_id).instantiate(tcx, trait_to_placeholder_args), + tcx.fn_sig(trait_m.def_id).instantiate(tcx, trait_to_impl_args), ) .fold_with(&mut collector); @@ -705,7 +687,7 @@ pub(super) fn collect_return_position_impl_trait_in_trait_tys<'tcx>( // Also, we only need to account for a difference in trait and impl args, // since we previously enforce that the trait method and impl method have the // same generics. - let num_trait_args = trait_to_impl_args.len(); + let num_trait_args = impl_trait_ref.args.len(); let num_impl_args = tcx.generics_of(impl_m.container_id(tcx)).own_params.len(); let ty = match ty.try_fold_with(&mut RemapHiddenTyRegions { tcx, @@ -1041,12 +1023,7 @@ fn check_region_bounds_on_impl_item<'tcx>( let trait_generics = tcx.generics_of(trait_m.def_id); let trait_params = trait_generics.own_counts().lifetimes; - debug!( - "check_region_bounds_on_impl_item: \ - trait_generics={:?} \ - impl_generics={:?}", - trait_generics, impl_generics - ); + debug!(?trait_generics, ?impl_generics); // Must have same number of early-bound lifetime parameters. // Unfortunately, if the user screws up the bounds, then this @@ -1710,8 +1687,7 @@ pub(super) fn compare_impl_const_raw( let trait_const_item = tcx.associated_item(trait_const_item_def); let impl_trait_ref = tcx.impl_trait_ref(impl_const_item.container_id(tcx)).unwrap().instantiate_identity(); - - debug!("compare_impl_const(impl_trait_ref={:?})", impl_trait_ref); + debug!(?impl_trait_ref); compare_number_of_generics(tcx, impl_const_item, trait_const_item, false)?; compare_generic_param_kinds(tcx, impl_const_item, trait_const_item, false)?; @@ -1722,6 +1698,7 @@ pub(super) fn compare_impl_const_raw( /// The equivalent of [compare_method_predicate_entailment], but for associated constants /// instead of associated functions. // FIXME(generic_const_items): If possible extract the common parts of `compare_{type,const}_predicate_entailment`. +#[instrument(level = "debug", skip(tcx))] fn compare_const_predicate_entailment<'tcx>( tcx: TyCtxt<'tcx>, impl_ct: ty::AssocItem, @@ -1736,13 +1713,14 @@ fn compare_const_predicate_entailment<'tcx>( // because we shouldn't really have to deal with lifetimes or // predicates. In fact some of this should probably be put into // shared functions because of DRY violations... - let impl_args = GenericArgs::identity_for_item(tcx, impl_ct.def_id); - let trait_to_impl_args = - impl_args.rebase_onto(tcx, impl_ct.container_id(tcx), impl_trait_ref.args); + let trait_to_impl_args = GenericArgs::identity_for_item(tcx, impl_ct.def_id).rebase_onto( + tcx, + impl_ct.container_id(tcx), + impl_trait_ref.args, + ); // Create a parameter environment that represents the implementation's - // method. - // Compute placeholder form of impl and trait const tys. + // associated const. let impl_ty = tcx.type_of(impl_ct_def_id).instantiate_identity(); let trait_ty = tcx.type_of(trait_ct.def_id).instantiate(tcx, trait_to_impl_args); @@ -1759,14 +1737,14 @@ fn compare_const_predicate_entailment<'tcx>( // The predicates declared by the impl definition, the trait and the // associated const in the trait are assumed. let impl_predicates = tcx.predicates_of(impl_ct_predicates.parent.unwrap()); - let mut hybrid_preds = impl_predicates.instantiate_identity(tcx); - hybrid_preds.predicates.extend( + let mut hybrid_preds = impl_predicates.instantiate_identity(tcx).predicates; + hybrid_preds.extend( trait_ct_predicates .instantiate_own(tcx, trait_to_impl_args) .map(|(predicate, _)| predicate), ); - let param_env = ty::ParamEnv::new(tcx.mk_clauses(&hybrid_preds.predicates), Reveal::UserFacing); + let param_env = ty::ParamEnv::new(tcx.mk_clauses(&hybrid_preds), Reveal::UserFacing); let param_env = traits::normalize_param_env_or_error( tcx, param_env, @@ -1776,7 +1754,7 @@ fn compare_const_predicate_entailment<'tcx>( let infcx = tcx.infer_ctxt().build(); let ocx = ObligationCtxt::new_with_diagnostics(&infcx); - let impl_ct_own_bounds = impl_ct_predicates.instantiate_own(tcx, impl_args); + let impl_ct_own_bounds = impl_ct_predicates.instantiate_own_identity(); for (predicate, span) in impl_ct_own_bounds { let cause = ObligationCause::misc(span, impl_ct_def_id); let predicate = ocx.normalize(&cause, param_env, predicate); @@ -1787,20 +1765,15 @@ fn compare_const_predicate_entailment<'tcx>( // There is no "body" here, so just pass dummy id. let impl_ty = ocx.normalize(&cause, param_env, impl_ty); - - debug!("compare_const_impl: impl_ty={:?}", impl_ty); + debug!(?impl_ty); let trait_ty = ocx.normalize(&cause, param_env, trait_ty); - - debug!("compare_const_impl: trait_ty={:?}", trait_ty); + debug!(?trait_ty); let err = ocx.sup(&cause, param_env, trait_ty, impl_ty); if let Err(terr) = err { - debug!( - "checking associated const for compatibility: impl ty {:?}, trait ty {:?}", - impl_ty, trait_ty - ); + debug!(?impl_ty, ?trait_ty); // Locate the Span containing just the type of the offending impl let (ty, _) = tcx.hir().expect_impl_item(impl_ct_def_id).expect_const(); @@ -1845,14 +1818,13 @@ fn compare_const_predicate_entailment<'tcx>( ocx.resolve_regions_and_report_errors(impl_ct_def_id, &outlives_env) } +#[instrument(level = "debug", skip(tcx))] pub(super) fn compare_impl_ty<'tcx>( tcx: TyCtxt<'tcx>, impl_ty: ty::AssocItem, trait_ty: ty::AssocItem, impl_trait_ref: ty::TraitRef<'tcx>, ) { - debug!("compare_impl_type(impl_trait_ref={:?})", impl_trait_ref); - let _: Result<(), ErrorGuaranteed> = try { compare_number_of_generics(tcx, impl_ty, trait_ty, false)?; compare_generic_param_kinds(tcx, impl_ty, trait_ty, false)?; @@ -1864,20 +1836,23 @@ pub(super) fn compare_impl_ty<'tcx>( /// The equivalent of [compare_method_predicate_entailment], but for associated types /// instead of associated functions. +#[instrument(level = "debug", skip(tcx))] fn compare_type_predicate_entailment<'tcx>( tcx: TyCtxt<'tcx>, impl_ty: ty::AssocItem, trait_ty: ty::AssocItem, impl_trait_ref: ty::TraitRef<'tcx>, ) -> Result<(), ErrorGuaranteed> { - let impl_args = GenericArgs::identity_for_item(tcx, impl_ty.def_id); - let trait_to_impl_args = - impl_args.rebase_onto(tcx, impl_ty.container_id(tcx), impl_trait_ref.args); + let trait_to_impl_args = GenericArgs::identity_for_item(tcx, impl_ty.def_id).rebase_onto( + tcx, + impl_ty.container_id(tcx), + impl_trait_ref.args, + ); let impl_ty_predicates = tcx.predicates_of(impl_ty.def_id); let trait_ty_predicates = tcx.predicates_of(trait_ty.def_id); - let impl_ty_own_bounds = impl_ty_predicates.instantiate_own(tcx, impl_args); + let impl_ty_own_bounds = impl_ty_predicates.instantiate_own_identity(); if impl_ty_own_bounds.len() == 0 { // Nothing to check. return Ok(()); @@ -1887,29 +1862,29 @@ fn compare_type_predicate_entailment<'tcx>( // `ObligationCause` (and the `FnCtxt`). This is what // `regionck_item` expects. let impl_ty_def_id = impl_ty.def_id.expect_local(); - debug!("compare_type_predicate_entailment: trait_to_impl_args={:?}", trait_to_impl_args); + debug!(?trait_to_impl_args); // The predicates declared by the impl definition, the trait and the // associated type in the trait are assumed. let impl_predicates = tcx.predicates_of(impl_ty_predicates.parent.unwrap()); - let mut hybrid_preds = impl_predicates.instantiate_identity(tcx); - hybrid_preds.predicates.extend( + let mut hybrid_preds = impl_predicates.instantiate_identity(tcx).predicates; + hybrid_preds.extend( trait_ty_predicates .instantiate_own(tcx, trait_to_impl_args) .map(|(predicate, _)| predicate), ); - - debug!("compare_type_predicate_entailment: bounds={:?}", hybrid_preds); + debug!(?hybrid_preds); let impl_ty_span = tcx.def_span(impl_ty_def_id); let normalize_cause = ObligationCause::misc(impl_ty_span, impl_ty_def_id); - let param_env = ty::ParamEnv::new(tcx.mk_clauses(&hybrid_preds.predicates), Reveal::UserFacing); + + let param_env = ty::ParamEnv::new(tcx.mk_clauses(&hybrid_preds), Reveal::UserFacing); let param_env = traits::normalize_param_env_or_error(tcx, param_env, normalize_cause); + debug!(caller_bounds=?param_env.caller_bounds()); + let infcx = tcx.infer_ctxt().build(); let ocx = ObligationCtxt::new_with_diagnostics(&infcx); - debug!("compare_type_predicate_entailment: caller_bounds={:?}", param_env.caller_bounds()); - for (predicate, span) in impl_ty_own_bounds { let cause = ObligationCause::misc(span, impl_ty_def_id); let predicate = ocx.normalize(&cause, param_env, predicate); @@ -2009,11 +1984,11 @@ pub(super) fn check_type_bounds<'tcx>( .explicit_item_bounds(trait_ty.def_id) .iter_instantiated_copied(tcx, rebased_args) .map(|(concrete_ty_bound, span)| { - debug!("check_type_bounds: concrete_ty_bound = {:?}", concrete_ty_bound); + debug!(?concrete_ty_bound); traits::Obligation::new(tcx, mk_cause(span), param_env, concrete_ty_bound) }) .collect(); - debug!("check_type_bounds: item_bounds={:?}", obligations); + debug!(item_bounds=?obligations); // Normalize predicates with the assumption that the GAT may always normalize // to its definition type. This should be the param-env we use to *prove* the @@ -2032,7 +2007,7 @@ pub(super) fn check_type_bounds<'tcx>( } else { ocx.normalize(&normalize_cause, normalize_param_env, obligation.predicate) }; - debug!("compare_projection_bounds: normalized predicate = {:?}", normalized_predicate); + debug!(?normalized_predicate); obligation.predicate = normalized_predicate; ocx.register_obligation(obligation); diff --git a/compiler/rustc_hir_typeck/src/upvar.rs b/compiler/rustc_hir_typeck/src/upvar.rs index 9e8a314bc4a..88982661c8f 100644 --- a/compiler/rustc_hir_typeck/src/upvar.rs +++ b/compiler/rustc_hir_typeck/src/upvar.rs @@ -2457,7 +2457,7 @@ fn truncate_capture_for_optimization( ) -> (Place<'_>, ty::UpvarCapture) { let is_shared_ref = |ty: Ty<'_>| matches!(ty.kind(), ty::Ref(.., hir::Mutability::Not)); - // Find the right-most deref (if any). All the projections that come after this + // Find the rightmost deref (if any). All the projections that come after this // are fields or other "in-place pointer adjustments"; these refer therefore to // data owned by whatever pointer is being dereferenced here. let idx = place.projections.iter().rposition(|proj| ProjectionKind::Deref == proj.kind); diff --git a/compiler/rustc_middle/src/ty/generics.rs b/compiler/rustc_middle/src/ty/generics.rs index 660686f4aa2..63534a3d017 100644 --- a/compiler/rustc_middle/src/ty/generics.rs +++ b/compiler/rustc_middle/src/ty/generics.rs @@ -395,7 +395,9 @@ impl<'tcx> GenericPredicates<'tcx> { EarlyBinder::bind(self.predicates).iter_instantiated_copied(tcx, args) } - pub fn instantiate_own_identity(self) -> impl Iterator<Item = (Clause<'tcx>, Span)> { + pub fn instantiate_own_identity( + self, + ) -> impl Iterator<Item = (Clause<'tcx>, Span)> + DoubleEndedIterator + ExactSizeIterator { EarlyBinder::bind(self.predicates).iter_identity_copied() } diff --git a/compiler/rustc_mir_build/src/build/scope.rs b/compiler/rustc_mir_build/src/build/scope.rs index dfc82f705a8..a7e56b8f589 100644 --- a/compiler/rustc_mir_build/src/build/scope.rs +++ b/compiler/rustc_mir_build/src/build/scope.rs @@ -1048,8 +1048,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // | +------------|outer_scope cache|--+ | // +------------------------------|middle_scope cache|------+ // - // Now, a new, inner-most scope is added along with a new drop into - // both inner-most and outer-most scopes: + // Now, a new, innermost scope is added along with a new drop into + // both innermost and outermost scopes: // // +------------------------------------------------------------+ // | +----------------------------------+ | @@ -1061,11 +1061,11 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // +----=----------------|invalid middle_scope cache|-----------+ // // If, when adding `drop(new)` we do not invalidate the cached blocks for both - // outer_scope and middle_scope, then, when building drops for the inner (right-most) + // outer_scope and middle_scope, then, when building drops for the inner (rightmost) // scope, the old, cached blocks, without `drop(new)` will get used, producing the // wrong results. // - // Note that this code iterates scopes from the inner-most to the outer-most, + // Note that this code iterates scopes from the innermost to the outermost, // invalidating caches of each scope visited. This way bare minimum of the // caches gets invalidated. i.e., if a new drop is added into the middle scope, the // cache of outer scope stays intact. diff --git a/compiler/rustc_mir_dataflow/src/value_analysis.rs b/compiler/rustc_mir_dataflow/src/value_analysis.rs index faee40faa3f..d0f62bd82d1 100644 --- a/compiler/rustc_mir_dataflow/src/value_analysis.rs +++ b/compiler/rustc_mir_dataflow/src/value_analysis.rs @@ -1177,7 +1177,7 @@ struct PlaceInfo<'tcx> { /// The projection used to go from parent to this node (only None for root). proj_elem: Option<TrackElem>, - /// The left-most child. + /// The leftmost child. first_child: Option<PlaceIndex>, /// Index of the sibling to the right of this node. diff --git a/compiler/rustc_parse/src/lexer/diagnostics.rs b/compiler/rustc_parse/src/lexer/diagnostics.rs index 41108c91f2e..e1f19beb53a 100644 --- a/compiler/rustc_parse/src/lexer/diagnostics.rs +++ b/compiler/rustc_parse/src/lexer/diagnostics.rs @@ -85,7 +85,7 @@ pub(super) fn report_suspicious_mismatch_block( } } - // Find the inner-most span candidate for final report + // Find the innermost span candidate for final report let candidate_span = matched_spans.into_iter().rev().find(|&(_, same_ident)| !same_ident).map(|(span, _)| span); diff --git a/compiler/rustc_target/src/callconv/loongarch.rs b/compiler/rustc_target/src/callconv/loongarch.rs index 4a21935623b..ffec76370d0 100644 --- a/compiler/rustc_target/src/callconv/loongarch.rs +++ b/compiler/rustc_target/src/callconv/loongarch.rs @@ -1,6 +1,7 @@ use crate::abi::call::{ArgAbi, ArgExtension, CastTarget, FnAbi, PassMode, Reg, RegKind, Uniform}; use crate::abi::{self, Abi, FieldsShape, HasDataLayout, Size, TyAbiInterface, TyAndLayout}; use crate::spec::HasTargetSpec; +use crate::spec::abi::Abi as SpecAbi; #[derive(Copy, Clone)] enum RegPassKind { @@ -359,3 +360,30 @@ where ); } } + +pub(crate) fn compute_rust_abi_info<'a, Ty, C>(cx: &C, fn_abi: &mut FnAbi<'a, Ty>, abi: SpecAbi) +where + Ty: TyAbiInterface<'a, C> + Copy, + C: HasDataLayout + HasTargetSpec, +{ + if abi == SpecAbi::RustIntrinsic { + return; + } + + let grlen = cx.data_layout().pointer_size.bits(); + + for arg in fn_abi.args.iter_mut() { + if arg.is_ignore() { + continue; + } + + // LLVM integers types do not differentiate between signed or unsigned integers. + // Some LoongArch instructions do not have a `.w` suffix version, they use all the + // GRLEN bits. By explicitly setting the `signext` or `zeroext` attribute + // according to signedness to avoid unnecessary integer extending instructions. + // + // This is similar to the RISC-V case, see + // https://github.com/rust-lang/rust/issues/114508 for details. + extend_integer_width(arg, grlen); + } +} diff --git a/compiler/rustc_target/src/callconv/mod.rs b/compiler/rustc_target/src/callconv/mod.rs index 5d120a68059..25b001b57e8 100644 --- a/compiler/rustc_target/src/callconv/mod.rs +++ b/compiler/rustc_target/src/callconv/mod.rs @@ -1,11 +1,14 @@ -use std::fmt; use std::str::FromStr; +use std::{fmt, iter}; pub use rustc_abi::{Reg, RegKind}; use rustc_macros::HashStable_Generic; use rustc_span::Symbol; -use crate::abi::{self, Abi, Align, HasDataLayout, Size, TyAbiInterface, TyAndLayout}; +use crate::abi::{ + self, Abi, AddressSpace, Align, HasDataLayout, Pointer, Size, TyAbiInterface, TyAndLayout, +}; +use crate::spec::abi::Abi as SpecAbi; use crate::spec::{self, HasTargetSpec, HasWasmCAbiOpt, HasX86AbiOpt, WasmCAbi}; mod aarch64; @@ -720,6 +723,118 @@ impl<'a, Ty> FnAbi<'a, Ty> { Ok(()) } + + pub fn adjust_for_rust_abi<C>(&mut self, cx: &C, abi: SpecAbi) + where + Ty: TyAbiInterface<'a, C> + Copy, + C: HasDataLayout + HasTargetSpec, + { + let spec = cx.target_spec(); + match &spec.arch[..] { + "x86" => x86::compute_rust_abi_info(cx, self, abi), + "riscv32" | "riscv64" => riscv::compute_rust_abi_info(cx, self, abi), + "loongarch64" => loongarch::compute_rust_abi_info(cx, self, abi), + _ => {} + }; + + for (arg_idx, arg) in self + .args + .iter_mut() + .enumerate() + .map(|(idx, arg)| (Some(idx), arg)) + .chain(iter::once((None, &mut self.ret))) + { + if arg.is_ignore() { + continue; + } + + if arg_idx.is_none() && arg.layout.size > Pointer(AddressSpace::DATA).size(cx) * 2 { + // Return values larger than 2 registers using a return area + // pointer. LLVM and Cranelift disagree about how to return + // values that don't fit in the registers designated for return + // values. LLVM will force the entire return value to be passed + // by return area pointer, while Cranelift will look at each IR level + // return value independently and decide to pass it in a + // register or not, which would result in the return value + // being passed partially in registers and partially through a + // return area pointer. + // + // While Cranelift may need to be fixed as the LLVM behavior is + // generally more correct with respect to the surface language, + // forcing this behavior in rustc itself makes it easier for + // other backends to conform to the Rust ABI and for the C ABI + // rustc already handles this behavior anyway. + // + // In addition LLVM's decision to pass the return value in + // registers or using a return area pointer depends on how + // exactly the return type is lowered to an LLVM IR type. For + // example `Option<u128>` can be lowered as `{ i128, i128 }` + // in which case the x86_64 backend would use a return area + // pointer, or it could be passed as `{ i32, i128 }` in which + // case the x86_64 backend would pass it in registers by taking + // advantage of an LLVM ABI extension that allows using 3 + // registers for the x86_64 sysv call conv rather than the + // officially specified 2 registers. + // + // FIXME: Technically we should look at the amount of available + // return registers rather than guessing that there are 2 + // registers for return values. In practice only a couple of + // architectures have less than 2 return registers. None of + // which supported by Cranelift. + // + // NOTE: This adjustment is only necessary for the Rust ABI as + // for other ABI's the calling convention implementations in + // rustc_target already ensure any return value which doesn't + // fit in the available amount of return registers is passed in + // the right way for the current target. + arg.make_indirect(); + continue; + } + + match arg.layout.abi { + Abi::Aggregate { .. } => {} + + // This is a fun case! The gist of what this is doing is + // that we want callers and callees to always agree on the + // ABI of how they pass SIMD arguments. If we were to *not* + // make these arguments indirect then they'd be immediates + // in LLVM, which means that they'd used whatever the + // appropriate ABI is for the callee and the caller. That + // means, for example, if the caller doesn't have AVX + // enabled but the callee does, then passing an AVX argument + // across this boundary would cause corrupt data to show up. + // + // This problem is fixed by unconditionally passing SIMD + // arguments through memory between callers and callees + // which should get them all to agree on ABI regardless of + // target feature sets. Some more information about this + // issue can be found in #44367. + // + // Note that the intrinsic ABI is exempt here as + // that's how we connect up to LLVM and it's unstable + // anyway, we control all calls to it in libstd. + Abi::Vector { .. } if abi != SpecAbi::RustIntrinsic && spec.simd_types_indirect => { + arg.make_indirect(); + continue; + } + + _ => continue, + } + // Compute `Aggregate` ABI. + + let is_indirect_not_on_stack = + matches!(arg.mode, PassMode::Indirect { on_stack: false, .. }); + assert!(is_indirect_not_on_stack); + + let size = arg.layout.size; + if !arg.layout.is_unsized() && size <= Pointer(AddressSpace::DATA).size(cx) { + // We want to pass small aggregates as immediates, but using + // an LLVM aggregate type for this leads to bad optimizations, + // so we pick an appropriately sized integer type instead. + arg.cast_to(Reg { kind: RegKind::Integer, size }); + } + } + } } impl FromStr for Conv { diff --git a/compiler/rustc_target/src/callconv/riscv.rs b/compiler/rustc_target/src/callconv/riscv.rs index be6bc701b49..f96169e6a61 100644 --- a/compiler/rustc_target/src/callconv/riscv.rs +++ b/compiler/rustc_target/src/callconv/riscv.rs @@ -7,6 +7,7 @@ use crate::abi::call::{ArgAbi, ArgExtension, CastTarget, FnAbi, PassMode, Reg, RegKind, Uniform}; use crate::abi::{self, Abi, FieldsShape, HasDataLayout, Size, TyAbiInterface, TyAndLayout}; use crate::spec::HasTargetSpec; +use crate::spec::abi::Abi as SpecAbi; #[derive(Copy, Clone)] enum RegPassKind { @@ -365,3 +366,29 @@ where ); } } + +pub(crate) fn compute_rust_abi_info<'a, Ty, C>(cx: &C, fn_abi: &mut FnAbi<'a, Ty>, abi: SpecAbi) +where + Ty: TyAbiInterface<'a, C> + Copy, + C: HasDataLayout + HasTargetSpec, +{ + if abi == SpecAbi::RustIntrinsic { + return; + } + + let xlen = cx.data_layout().pointer_size.bits(); + + for arg in fn_abi.args.iter_mut() { + if arg.is_ignore() { + continue; + } + + // LLVM integers types do not differentiate between signed or unsigned integers. + // Some RISC-V instructions do not have a `.w` suffix version, they use all the + // XLEN bits. By explicitly setting the `signext` or `zeroext` attribute + // according to signedness to avoid unnecessary integer extending instructions. + // + // See https://github.com/rust-lang/rust/issues/114508 for details. + extend_integer_width(arg, xlen); + } +} diff --git a/compiler/rustc_target/src/callconv/x86.rs b/compiler/rustc_target/src/callconv/x86.rs index 40c3e7a891a..e907beecb38 100644 --- a/compiler/rustc_target/src/callconv/x86.rs +++ b/compiler/rustc_target/src/callconv/x86.rs @@ -1,6 +1,9 @@ use crate::abi::call::{ArgAttribute, FnAbi, PassMode, Reg, RegKind}; -use crate::abi::{Abi, Align, HasDataLayout, TyAbiInterface, TyAndLayout}; +use crate::abi::{ + Abi, AddressSpace, Align, Float, HasDataLayout, Pointer, TyAbiInterface, TyAndLayout, +}; use crate::spec::HasTargetSpec; +use crate::spec::abi::Abi as SpecAbi; #[derive(PartialEq)] pub(crate) enum Flavor { @@ -207,3 +210,35 @@ pub(crate) fn fill_inregs<'a, Ty, C>( } } } + +pub(crate) fn compute_rust_abi_info<'a, Ty, C>(cx: &C, fn_abi: &mut FnAbi<'a, Ty>, abi: SpecAbi) +where + Ty: TyAbiInterface<'a, C> + Copy, + C: HasDataLayout + HasTargetSpec, +{ + // Avoid returning floats in x87 registers on x86 as loading and storing from x87 + // registers will quiet signalling NaNs. Also avoid using SSE registers since they + // are not always available (depending on target features). + if !fn_abi.ret.is_ignore() + // Intrinsics themselves are not actual "real" functions, so theres no need to change their ABIs. + && abi != SpecAbi::RustIntrinsic + { + let has_float = match fn_abi.ret.layout.abi { + Abi::Scalar(s) => matches!(s.primitive(), Float(_)), + Abi::ScalarPair(s1, s2) => { + matches!(s1.primitive(), Float(_)) || matches!(s2.primitive(), Float(_)) + } + _ => false, // anyway not passed via registers on x86 + }; + if has_float { + if fn_abi.ret.layout.size <= Pointer(AddressSpace::DATA).size(cx) { + // Same size or smaller than pointer, return in a register. + fn_abi.ret.cast_to(Reg { kind: RegKind::Integer, size: fn_abi.ret.layout.size }); + } else { + // Larger than a pointer, return indirectly. + fn_abi.ret.make_indirect(); + } + return; + } + } +} diff --git a/compiler/rustc_ty_utils/src/abi.rs b/compiler/rustc_ty_utils/src/abi.rs index 09b9ecb3486..48149a08de8 100644 --- a/compiler/rustc_ty_utils/src/abi.rs +++ b/compiler/rustc_ty_utils/src/abi.rs @@ -1,7 +1,7 @@ use std::iter; -use rustc_abi::Primitive::{Float, Pointer}; -use rustc_abi::{Abi, AddressSpace, PointerKind, Scalar, Size}; +use rustc_abi::Primitive::Pointer; +use rustc_abi::{Abi, PointerKind, Scalar, Size}; use rustc_hir as hir; use rustc_hir::lang_items::LangItem; use rustc_middle::bug; @@ -13,8 +13,7 @@ use rustc_middle::ty::{self, InstanceKind, Ty, TyCtxt}; use rustc_session::config::OptLevel; use rustc_span::def_id::DefId; use rustc_target::abi::call::{ - ArgAbi, ArgAttribute, ArgAttributes, ArgExtension, Conv, FnAbi, PassMode, Reg, RegKind, - RiscvInterruptKind, + ArgAbi, ArgAttribute, ArgAttributes, ArgExtension, Conv, FnAbi, PassMode, RiscvInterruptKind, }; use rustc_target::spec::abi::Abi as SpecAbi; use tracing::debug; @@ -678,6 +677,8 @@ fn fn_abi_adjust_for_abi<'tcx>( let tcx = cx.tcx(); if abi == SpecAbi::Rust || abi == SpecAbi::RustCall || abi == SpecAbi::RustIntrinsic { + fn_abi.adjust_for_rust_abi(cx, abi); + // Look up the deduced parameter attributes for this function, if we have its def ID and // we're optimizing in non-incremental mode. We'll tag its parameters with those attributes // as appropriate. @@ -688,125 +689,9 @@ fn fn_abi_adjust_for_abi<'tcx>( &[] }; - let fixup = |arg: &mut ArgAbi<'tcx, Ty<'tcx>>, arg_idx: Option<usize>| { + for (arg_idx, arg) in fn_abi.args.iter_mut().enumerate() { if arg.is_ignore() { - return; - } - - // Avoid returning floats in x87 registers on x86 as loading and storing from x87 - // registers will quiet signalling NaNs. Also avoid using SSE registers since they - // are not always available (depending on target features). - if tcx.sess.target.arch == "x86" - && arg_idx.is_none() - // Intrinsics themselves are not actual "real" functions, so theres no need to - // change their ABIs. - && abi != SpecAbi::RustIntrinsic - { - let has_float = match arg.layout.abi { - Abi::Scalar(s) => matches!(s.primitive(), Float(_)), - Abi::ScalarPair(s1, s2) => { - matches!(s1.primitive(), Float(_)) || matches!(s2.primitive(), Float(_)) - } - _ => false, // anyway not passed via registers on x86 - }; - if has_float { - if arg.layout.size <= Pointer(AddressSpace::DATA).size(cx) { - // Same size or smaller than pointer, return in a register. - arg.cast_to(Reg { kind: RegKind::Integer, size: arg.layout.size }); - } else { - // Larger than a pointer, return indirectly. - arg.make_indirect(); - } - return; - } - } - - if arg_idx.is_none() && arg.layout.size > Pointer(AddressSpace::DATA).size(cx) * 2 { - // Return values larger than 2 registers using a return area - // pointer. LLVM and Cranelift disagree about how to return - // values that don't fit in the registers designated for return - // values. LLVM will force the entire return value to be passed - // by return area pointer, while Cranelift will look at each IR level - // return value independently and decide to pass it in a - // register or not, which would result in the return value - // being passed partially in registers and partially through a - // return area pointer. - // - // While Cranelift may need to be fixed as the LLVM behavior is - // generally more correct with respect to the surface language, - // forcing this behavior in rustc itself makes it easier for - // other backends to conform to the Rust ABI and for the C ABI - // rustc already handles this behavior anyway. - // - // In addition LLVM's decision to pass the return value in - // registers or using a return area pointer depends on how - // exactly the return type is lowered to an LLVM IR type. For - // example `Option<u128>` can be lowered as `{ i128, i128 }` - // in which case the x86_64 backend would use a return area - // pointer, or it could be passed as `{ i32, i128 }` in which - // case the x86_64 backend would pass it in registers by taking - // advantage of an LLVM ABI extension that allows using 3 - // registers for the x86_64 sysv call conv rather than the - // officially specified 2 registers. - // - // FIXME: Technically we should look at the amount of available - // return registers rather than guessing that there are 2 - // registers for return values. In practice only a couple of - // architectures have less than 2 return registers. None of - // which supported by Cranelift. - // - // NOTE: This adjustment is only necessary for the Rust ABI as - // for other ABI's the calling convention implementations in - // rustc_target already ensure any return value which doesn't - // fit in the available amount of return registers is passed in - // the right way for the current target. - arg.make_indirect(); - return; - } - - match arg.layout.abi { - Abi::Aggregate { .. } => {} - - // This is a fun case! The gist of what this is doing is - // that we want callers and callees to always agree on the - // ABI of how they pass SIMD arguments. If we were to *not* - // make these arguments indirect then they'd be immediates - // in LLVM, which means that they'd used whatever the - // appropriate ABI is for the callee and the caller. That - // means, for example, if the caller doesn't have AVX - // enabled but the callee does, then passing an AVX argument - // across this boundary would cause corrupt data to show up. - // - // This problem is fixed by unconditionally passing SIMD - // arguments through memory between callers and callees - // which should get them all to agree on ABI regardless of - // target feature sets. Some more information about this - // issue can be found in #44367. - // - // Note that the intrinsic ABI is exempt here as - // that's how we connect up to LLVM and it's unstable - // anyway, we control all calls to it in libstd. - Abi::Vector { .. } - if abi != SpecAbi::RustIntrinsic && tcx.sess.target.simd_types_indirect => - { - arg.make_indirect(); - return; - } - - _ => return, - } - // Compute `Aggregate` ABI. - - let is_indirect_not_on_stack = - matches!(arg.mode, PassMode::Indirect { on_stack: false, .. }); - assert!(is_indirect_not_on_stack, "{:?}", arg); - - let size = arg.layout.size; - if !arg.layout.is_unsized() && size <= Pointer(AddressSpace::DATA).size(cx) { - // We want to pass small aggregates as immediates, but using - // an LLVM aggregate type for this leads to bad optimizations, - // so we pick an appropriately sized integer type instead. - arg.cast_to(Reg { kind: RegKind::Integer, size }); + continue; } // If we deduced that this parameter was read-only, add that to the attribute list now. @@ -814,9 +699,7 @@ fn fn_abi_adjust_for_abi<'tcx>( // The `readonly` parameter only applies to pointers, so we can only do this if the // argument was passed indirectly. (If the argument is passed directly, it's an SSA // value, so it's implicitly immutable.) - if let (Some(arg_idx), &mut PassMode::Indirect { ref mut attrs, .. }) = - (arg_idx, &mut arg.mode) - { + if let &mut PassMode::Indirect { ref mut attrs, .. } = &mut arg.mode { // The `deduced_param_attrs` list could be empty if this is a type of function // we can't deduce any parameters for, so make sure the argument index is in // bounds. @@ -827,11 +710,6 @@ fn fn_abi_adjust_for_abi<'tcx>( } } } - }; - - fixup(&mut fn_abi.ret, None); - for (arg_idx, arg) in fn_abi.args.iter_mut().enumerate() { - fixup(arg, Some(arg_idx)); } } else { fn_abi diff --git a/compiler/rustc_type_ir/src/binder.rs b/compiler/rustc_type_ir/src/binder.rs index f20beb79750..c06a578d8ec 100644 --- a/compiler/rustc_type_ir/src/binder.rs +++ b/compiler/rustc_type_ir/src/binder.rs @@ -496,8 +496,8 @@ where /// Similar to [`instantiate_identity`](EarlyBinder::instantiate_identity), /// but on an iterator of values that deref to a `TypeFoldable`. - pub fn iter_identity_copied(self) -> impl Iterator<Item = <Iter::Item as Deref>::Target> { - self.value.into_iter().map(|v| *v) + pub fn iter_identity_copied(self) -> IterIdentityCopied<Iter> { + IterIdentityCopied { it: self.value.into_iter() } } } @@ -546,6 +546,44 @@ where { } +pub struct IterIdentityCopied<Iter: IntoIterator> { + it: Iter::IntoIter, +} + +impl<Iter: IntoIterator> Iterator for IterIdentityCopied<Iter> +where + Iter::Item: Deref, + <Iter::Item as Deref>::Target: Copy, +{ + type Item = <Iter::Item as Deref>::Target; + + fn next(&mut self) -> Option<Self::Item> { + self.it.next().map(|i| *i) + } + + fn size_hint(&self) -> (usize, Option<usize>) { + self.it.size_hint() + } +} + +impl<Iter: IntoIterator> DoubleEndedIterator for IterIdentityCopied<Iter> +where + Iter::IntoIter: DoubleEndedIterator, + Iter::Item: Deref, + <Iter::Item as Deref>::Target: Copy, +{ + fn next_back(&mut self) -> Option<Self::Item> { + self.it.next_back().map(|i| *i) + } +} + +impl<Iter: IntoIterator> ExactSizeIterator for IterIdentityCopied<Iter> +where + Iter::IntoIter: ExactSizeIterator, + Iter::Item: Deref, + <Iter::Item as Deref>::Target: Copy, +{ +} pub struct EarlyBinderIter<I, T> { t: T, _tcx: PhantomData<I>, |