MIR - Fix a bit of invalid MIR

5 files changed, 31 insertions, 9 deletions

diff --git a/src/mir/check.cpp b/src/mir/check.cpp
index 9e83df8c..382694a7 100644
--- a/src/mir/check.cpp
+++ b/src/mir/check.cpp
@@ -543,10 +543,12 @@ void MIR_Validate(const StaticTraitResolve& resolve, const ::HIR::ItemPath& path
                         ),
                     (DstMeta,
                         // TODO: Ensure that the input type is a: Generic, Array, or DST
+                        MIR_ASSERT(state, e.val.is_Deref(), "DstMeta requires a deref as input");
                         // TODO: Check return type
                         ),
                     (DstPtr,
                         // TODO: Ensure that the input type is a DST
+                        MIR_ASSERT(state, e.val.is_Deref(), "DstPtr requires a deref as input");
                         // TODO: Check return type
                         ),
                     (MakeDst,
diff --git a/src/mir/cleanup.cpp b/src/mir/cleanup.cpp
index 8a5ee1dc..f790c78a 100644
--- a/src/mir/cleanup.cpp
+++ b/src/mir/cleanup.cpp
@@ -120,13 +120,33 @@ const ::HIR::Literal* MIR_Cleanup_GetConstant(const Span& sp, const StaticTraitR
 
         if( best_impl )
         {
-            out_ty = best_impl->m_constants.find(pe.item)->second.data.m_type.clone();
+            const auto& val = best_impl->m_constants.find(pe.item)->second.data;
+            out_ty = val.m_type.clone();
             // TODO: Obtain `out_ty` by monomorphising the type in the trait.
-            return &best_impl->m_constants.find(pe.item)->second.data.m_value_res;
+            return &val.m_value_res;
         }
         ),
     (UfcsInherent,
+        const ::HIR::TypeImpl* best_impl = nullptr;
         // TODO: Associated constants (inherent)
+        resolve.m_crate.find_type_impls(*pe.type, [&](const auto& ty)->const auto& { return ty; },
+            [&](const auto& impl) {
+                auto it = impl.m_constants.find(pe.item);
+                if( it == impl.m_constants.end() )
+                    return false;
+                // TODO: Bounds checks.
+                // TODO: Impl specialisation?
+                best_impl = &impl;
+                return it->second.is_specialisable;
+            });
+        if( best_impl )
+        {
+            const auto& val = best_impl->m_constants.find(pe.item)->second.data;
+            if( monomorphise_type_needed(val.m_type) )
+                TODO(sp, "Monomorphise constant type - " << val.m_type << " for " << path);
+            out_ty = val.m_type.clone();
+            return &val.m_value_res;
+        }
         )
     )
     return nullptr;
diff --git a/src/mir/from_hir.cpp b/src/mir/from_hir.cpp
index 4f72099d..60084e3d 100644
--- a/src/mir/from_hir.cpp
+++ b/src/mir/from_hir.cpp
@@ -1181,7 +1181,7 @@ namespace {
                     {
                         // HACK: FixedSizeArray uses `A: Unsize<[T]>` which will lead to the above code not working (as the size isn't known).
                         // - Maybe _Meta on the `&A` would work as a stopgap (since A: Sized, it won't collide with &[T] or similar)
-                        auto size_lval = m_builder.lvalue_or_temp( node.span(), ::HIR::TypeRef(::HIR::CoreType::Usize), ::MIR::RValue::make_DstMeta({ ptr_lval.clone() }) );
+                        auto size_lval = m_builder.lvalue_or_temp( node.span(), ::HIR::TypeRef(::HIR::CoreType::Usize), ::MIR::RValue::make_DstMeta({ ::MIR::LValue::make_Deref({ box$(ptr_lval.clone()) }) }) );
                         m_builder.set_result( node.span(), ::MIR::RValue::make_MakeDst({ mv$(ptr_lval), mv$(size_lval) }) );
                     }
                     else
diff --git a/src/mir/from_hir_match.cpp b/src/mir/from_hir_match.cpp
index 183d6418..008bef0c 100644
--- a/src/mir/from_hir_match.cpp
+++ b/src/mir/from_hir_match.cpp
@@ -3677,6 +3677,8 @@ void DecisionTreeGen::generate_branches_Slice(
         ERROR(sp, E0000, "Non-exhaustive match over " << ty);
     }
 
+    auto val_len = m_builder.lvalue_or_temp(sp, ::HIR::CoreType::Usize, ::MIR::RValue::make_DstMeta({ val.clone() }));
+
     // NOTE: Un-deref the slice
     ASSERT_BUG(sp, val.is_Deref(), "slice matches must be passed a deref");
     auto tmp = mv$( *val.as_Deref().val );
@@ -3689,8 +3691,6 @@ void DecisionTreeGen::generate_branches_Slice(
     // - Binary search
     // - Sequential comparisons
 
-    auto val_len = m_builder.lvalue_or_temp(sp, ::HIR::CoreType::Usize, ::MIR::RValue::make_DstMeta({ val.clone() }));
-
     // TODO: Binary search instead.
     for( const auto& branch : branches.fixed_arms )
     {
diff --git a/src/trans/codegen_c.cpp b/src/trans/codegen_c.cpp
index 3f6c69be..e29f2a40 100644
--- a/src/trans/codegen_c.cpp
+++ b/src/trans/codegen_c.cpp
@@ -1453,17 +1453,17 @@ namespace {
             TU_MATCHA( (path.m_data), (pe),
             (Generic,
                 if( pe.m_params.m_types.size() > 0 )
-                    MIR_TODO(*m_mir_res, "Paths with generics " << path);
+                    MIR_TODO(*m_mir_res, "get_literal_for_const - Paths with generics " << path);
                 return m_crate.get_constant_by_path(Span(), pe.m_path).m_value_res;
                 ),
             (UfcsUnknown,
-                MIR_BUG(*m_mir_res, "UfcsUnknown " << path);
+                MIR_BUG(*m_mir_res, "get_literal_for_const - UfcsUnknown " << path);
                 ),
             (UfcsKnown,
-                MIR_TODO(*m_mir_res, "UfcsKnown " << path);
+                MIR_TODO(*m_mir_res, "get_literal_for_const - UfcsKnown " << path);
                 ),
             (UfcsInherent,
-                MIR_TODO(*m_mir_res, "UfcsInherent " << path);
+                MIR_TODO(*m_mir_res, "get_literal_for_const - UfcsInherent " << path);
                 )
             )
             throw "";