diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/hir_typeck/expr_cs.cpp | 85 |
1 files changed, 82 insertions, 3 deletions
diff --git a/src/hir_typeck/expr_cs.cpp b/src/hir_typeck/expr_cs.cpp index fb55fcc6..3504bdcd 100644 --- a/src/hir_typeck/expr_cs.cpp +++ b/src/hir_typeck/expr_cs.cpp @@ -595,6 +595,7 @@ namespace { TRACE_FUNCTION_F(&node << " ... as " << node.m_res_type); this->context.add_ivars( node.m_value->m_res_type ); + // TODO: Only revisit if the cast type requires inferring. this->context.add_revisit(node); node.m_value->visit( *this ); @@ -609,8 +610,7 @@ namespace { this->context.add_ivars( node.m_value->m_res_type ); this->context.add_ivars( node.m_index->m_res_type ); - const auto& op_trait = this->context.m_crate.get_lang_item_path(node.span(), "index"); - this->context.equate_types_assoc(node.span(), node.m_res_type, op_trait, ::make_vec1(node.m_index->m_res_type.clone()), node.m_value->m_res_type.clone(), "Output"); + this->context.add_revisit(node); node.m_value->visit( *this ); node.m_index->visit( *this ); @@ -1299,7 +1299,86 @@ namespace { no_revisit(node); } void visit(::HIR::ExprNode_Index& node) override { - no_revisit(node); + const auto& lang_Index = this->context.m_crate.get_lang_item_path(node.span(), "index"); + const auto& val_ty = this->context.get_type(node.m_value->m_res_type); + const auto& idx_ty = this->context.get_type(node.m_index->m_res_type); + DEBUG("(Index) val=" << val_ty << ", idx=" << idx_ty << ""); + + + // NOTE: Indexing triggers autoderef + unsigned int deref_count = 0; + ::HIR::TypeRef tmp_type; // Temporary type used for handling Deref + const auto* current_ty = &node.m_value->m_res_type; + ::std::vector< ::HIR::TypeRef> deref_res_types; + + // TODO: (CHECK) rustc doesn't use the index value type when finding the indexable item, mrustc does. + ::HIR::PathParams trait_pp; + trait_pp.m_types.push_back( idx_ty.clone() ); + do { + const auto& ty = this->context.get_type(*current_ty); + DEBUG("(Index): (: " << ty << ")[: " << trait_pp.m_types[0] << "]"); + + ::HIR::TypeRef possible_index_type; + ::HIR::TypeRef possible_res_type; + unsigned int count = 0; + bool rv = this->context.m_resolve.find_trait_impls(node.span(), lang_Index, trait_pp, ty, [&](const auto& ty, const auto& args, const auto& assoc) { + assert( args.m_types.size() == 1 ); + const auto& impl_index = args.m_types[0]; + + auto cmp = impl_index.compare_with_placeholders(node.span(), trait_pp.m_types[0], this->context.m_ivars.callback_resolve_infer()); + if( cmp == ::HIR::Compare::Unequal) { + return false; + } + possible_res_type = assoc.at("Output").clone(); + count += 1; + if( cmp == ::HIR::Compare::Equal ) { + return true; + } + possible_index_type = impl_index.clone(); + return false; + }); + if( rv ) { + this->context.equate_types(node.span(), node.m_res_type, possible_res_type); + break; + } + else if( count == 1 ) { + assert( possible_index_type != ::HIR::TypeRef() ); + this->context.equate_types(node.span(), node.m_index->m_res_type, possible_index_type); + this->context.equate_types(node.span(), node.m_res_type, possible_res_type); + break; + } + else if( count > 1 ) { + // Multiple fuzzy matches, don't keep dereferencing until we know. + current_ty = nullptr; + break; + } + else { + // Either no matches, or multiple fuzzy matches + } + + deref_count += 1; + current_ty = this->context.m_resolve.autoderef(node.span(), ty, tmp_type); + if( current_ty ) + deref_res_types.push_back( current_ty->clone() ); + } while( current_ty ); + + if( current_ty ) + { + if( deref_count > 0 ) + DEBUG("Adding " << deref_count << " dereferences"); + assert( deref_count == deref_res_types.size() ); + while( !deref_res_types.empty() ) + { + auto ty = mv$(deref_res_types.back()); + deref_res_types.pop_back(); + node.m_value = ::HIR::ExprNodeP( new ::HIR::ExprNode_Deref(node.span(), mv$(node.m_value)) ); + node.m_value->m_res_type = mv$(ty); + this->context.add_ivars( node.m_value->m_res_type ); + deref_count -= 1; + } + + m_completed = true; + } } void visit(::HIR::ExprNode_Deref& node) override { no_revisit(node); |