From: Philip Herron Date: Mon, 13 Mar 2023 16:49:36 +0000 (+0000) Subject: gccrs: Remove solve_missing_mappings_from_this to handle covariants X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=9ace79ff7ec52b15708469a04b28070bfeed5eb3;p=people%2Fms%2Fgcc.git gccrs: Remove solve_missing_mappings_from_this to handle covariants change how we monomorphize dyn-items when we need to compute the generics We might have a trait item such as: impl<'a, T> FnLike<&'a T, &'a T> for Identity { fn call(&self, arg: &'a T) -> &'a T { ... } } Which ended up monomorphized badly to: const isize & const & >::call<& isize> (const struct example::Identity & const self, const isize & const & const arg) This is wrong because it turned into a double reference type becasuse this bug was consistent bugs were not picked up but this is not correct. We now reuse our type inference infrastructure to solve the parameters instead. Fixes #1984 gcc/rust/ChangeLog: * backend/rust-compile.cc: use unify_and instead * typecheck/rust-tyty-subst.cc (SubstitutionRef::solve_missing_mappings_from_this): remove * typecheck/rust-tyty-subst.h: update header Signed-off-by: Philip Herron --- diff --git a/gcc/rust/backend/rust-compile.cc b/gcc/rust/backend/rust-compile.cc index a01662c6da5..2c4699264f0 100644 --- a/gcc/rust/backend/rust-compile.cc +++ b/gcc/rust/backend/rust-compile.cc @@ -21,6 +21,8 @@ #include "rust-compile-implitem.h" #include "rust-hir-type-bounds.h" #include "rust-compile-type.h" +#include "rust-substitution-mapper.h" +#include "rust-type-util.h" namespace Rust { namespace Compile { @@ -299,11 +301,6 @@ HIRCompileBase::compute_address_for_trait_item ( = self_bound->lookup_associated_item (ref->get_identifier ()); rust_assert (!associated_self_item.is_error ()); - TyTy::BaseType *mono1 = associated_self_item.get_tyty_for_receiver (self); - rust_assert (mono1 != nullptr); - rust_assert (mono1->get_kind () == TyTy::TypeKind::FNDEF); - TyTy::FnType *assocated_item_ty1 = static_cast (mono1); - // Lookup the impl-block for the associated impl_item if it exists HIR::Function *associated_function = nullptr; for (auto &impl_item : associated_impl_block->get_impl_items ()) @@ -333,10 +330,14 @@ HIRCompileBase::compute_address_for_trait_item ( if (lookup_fntype->needs_substitution ()) { - TyTy::SubstitutionArgumentMappings mappings - = assocated_item_ty1->solve_missing_mappings_from_this ( - *trait_item_fntype, *lookup_fntype); - lookup_fntype = lookup_fntype->handle_substitions (mappings); + TyTy::BaseType *infer + = Resolver::SubstMapper::InferSubst (lookup_fntype, Location ()); + infer + = Resolver::unify_site (infer->get_ref (), + TyTy::TyWithLocation (trait_item_fntype), + TyTy::TyWithLocation (infer), Location ()); + rust_assert (infer->get_kind () == TyTy::TypeKind::FNDEF); + lookup_fntype = static_cast (infer); } return CompileInherentImplItem::Compile (associated_function, ctx, diff --git a/gcc/rust/typecheck/rust-tyty-subst.cc b/gcc/rust/typecheck/rust-tyty-subst.cc index 6b77a9ee398..db31ff9323f 100644 --- a/gcc/rust/typecheck/rust-tyty-subst.cc +++ b/gcc/rust/typecheck/rust-tyty-subst.cc @@ -821,57 +821,6 @@ SubstitutionRef::solve_mappings_from_receiver_for_self ( mappings.get_locus ()); } -SubstitutionArgumentMappings -SubstitutionRef::solve_missing_mappings_from_this (SubstitutionRef &ref, - SubstitutionRef &to) -{ - rust_assert (!ref.needs_substitution ()); - rust_assert (needs_substitution ()); - rust_assert (get_num_substitutions () == ref.get_num_substitutions ()); - - Location locus = used_arguments.get_locus (); - std::vector resolved_mappings; - - std::map> substs; - for (size_t i = 0; i < get_num_substitutions (); i++) - { - SubstitutionParamMapping &a = substitutions.at (i); - SubstitutionParamMapping &b = ref.substitutions.at (i); - - if (a.need_substitution ()) - { - const BaseType *root = a.get_param_ty ()->resolve ()->get_root (); - rust_assert (root->get_kind () == TyTy::TypeKind::PARAM); - const ParamType *p = static_cast (root); - - substs[p->get_ty_ref ()] = {static_cast (p->clone ()), - b.get_param_ty ()->resolve ()}; - } - } - - for (auto it = substs.begin (); it != substs.end (); it++) - { - HirId param_id = it->first; - BaseType *arg = it->second.second; - - const SubstitutionParamMapping *associate_param = nullptr; - for (SubstitutionParamMapping &p : to.substitutions) - { - if (p.get_param_ty ()->get_ty_ref () == param_id) - { - associate_param = &p; - break; - } - } - - rust_assert (associate_param != nullptr); - SubstitutionArg argument (associate_param, arg); - resolved_mappings.push_back (std::move (argument)); - } - - return SubstitutionArgumentMappings (resolved_mappings, {}, locus); -} - Resolver::AssociatedImplTrait * SubstitutionRef::lookup_associated_impl (const SubstitutionParamMapping &subst, const TypeBoundPredicate &bound, diff --git a/gcc/rust/typecheck/rust-tyty-subst.h b/gcc/rust/typecheck/rust-tyty-subst.h index 365fdb6c042..b5a41819fd4 100644 --- a/gcc/rust/typecheck/rust-tyty-subst.h +++ b/gcc/rust/typecheck/rust-tyty-subst.h @@ -291,11 +291,12 @@ public: SubstitutionArgumentMappings solve_mappings_from_receiver_for_self ( SubstitutionArgumentMappings &mappings) const; - // TODO comment - SubstitutionArgumentMappings - solve_missing_mappings_from_this (SubstitutionRef &ref, SubstitutionRef &to); - - // TODO comment + // Given a type such as: + // + // fn(a:&X, b:Y) -> (...) + // + // This function will inject implicit inference variables for the type + // parameters X and Y BaseType *infer_substitions (Location locus); // this clears any possible projections from higher ranked trait bounds which