diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/hir_typeck/expr_cs.cpp | 59 |
1 files changed, 45 insertions, 14 deletions
diff --git a/src/hir_typeck/expr_cs.cpp b/src/hir_typeck/expr_cs.cpp index 1e0ef177..975c6b47 100644 --- a/src/hir_typeck/expr_cs.cpp +++ b/src/hir_typeck/expr_cs.cpp @@ -4886,16 +4886,13 @@ namespace { return ; } - //enum class List { - // CoerceTo, - // CoerceFrom, - // UnsizeTo, - // UnsizeFrom, - //}; + enum class DedupKeep { + Both, + Left, + Right, + }; struct H { - // De-duplicate list (taking into account other ivars) - // - TODO: Use the direction and do a fuzzy equality based on coercion possibility - static void dedup_type_list(const Context& context, ::std::vector< ::HIR::TypeRef>& list) { + static void dedup_type_list_with(::std::vector< ::HIR::TypeRef>& list, ::std::function<DedupKeep(const ::HIR::TypeRef& l, const ::HIR::TypeRef& r)> cmp) { if( list.size() <= 1 ) return ; @@ -4903,8 +4900,16 @@ namespace { { bool found = false; for( auto it2 = list.begin(); it2 != it; ++ it2 ) { - //if( context.m_ivars.types_equal( **it, **it2 ) ) { - if( H::equal_to(context, *it, *it2) ) { + auto action = cmp(*it, *it2); + if( action != DedupKeep::Both ) + { + if( action == DedupKeep::Right ) { + //DEBUG("Keep " << *it << ", toss " << *it2); + } + else { + ::std::swap(*it2, *it); + //DEBUG("Keep " << *it << ", toss " << *it2 << " (swapped)"); + } found = true; break; } @@ -4917,6 +4922,11 @@ namespace { } } } + // De-duplicate list (taking into account other ivars) + // - TODO: Use the direction and do a fuzzy equality based on coercion possibility + static void dedup_type_list(const Context& context, ::std::vector< ::HIR::TypeRef>& list) { + dedup_type_list_with(list, [&context](const auto& l, const auto& r){ return H::equal_to(context, l, r) ? DedupKeep::Left : DedupKeep::Both; }); + } // Types are equal from the view of being coercion targets // - Inequality here means that the targets could coexist (e.g. &[u8; N] and &[u8]) @@ -5077,10 +5087,9 @@ namespace { { TRACE_FUNCTION_F(i); - // TODO: Some cases lead to two possibilities that compare different (due to inferrence) but are actually the same. - // - The above dedup should probably be aware of the way the types are used (for coercions). - // TODO: Dedup based on context. + // TODO: Dedup based on context? + // - The dedup should probably be aware of the way the types are used (for coercions). H::dedup_type_list(context, ivar_ent.types_coerce_to); H::dedup_type_list(context, ivar_ent.types_unsize_to); H::dedup_type_list(context, ivar_ent.types_coerce_from); @@ -5105,6 +5114,28 @@ namespace { DEBUG("-- " << ty_l << " FROM=Coerce:[" << ivar_ent.types_coerce_from << "] / Unsize:[" << ivar_ent.types_unsize_from << "]," << " TO=Coerce:[" << ivar_ent.types_coerce_to << "] / Unsize:[" << ivar_ent.types_unsize_to << "]"); + // TODO: Find an entry in the `types_unsize_from` list that all other entries can unsize to + H::dedup_type_list_with(ivar_ent.types_unsize_from, [&](const auto& l, const auto& r) { + // &T and T + TU_IFLET( ::HIR::TypeRef::Data, l.m_data, Borrow, le, + TU_IFLET( ::HIR::TypeRef::Data, r.m_data, Borrow, re, + ) + else { + // if *le.inner == r, return DedupKeep::Right + if( context.m_ivars.types_equal(*le.inner, r) ) + return DedupKeep::Right; + } + ) + else { + TU_IFLET( ::HIR::TypeRef::Data, r.m_data, Borrow, re, + // if *re.inner == l, return DedupKeep::Left + if( context.m_ivars.types_equal(*re.inner, l) ) + return DedupKeep::Left; + ) + } + return DedupKeep::Both; + }); + // HACK: Merge into a single list. ::std::vector< ::HIR::TypeRef> types_from_o; const auto* types_from_p = &types_from_o; |