move towards structure construction / deconstruction

src/backend/into_crane.rs

@@ -406,8 +406,30 @@ impl<M: Module> Backend<M> {
                 }
             }
 
-            Expression::Construct(_, _, _, _) => unimplemented!(),
-            Expression::FieldRef(_, _, _, _) => unimplemented!(),
+            Expression::Construct(_, ty, name, fields) => {
+                let Type::Structure(fields) = ty else {
+                    panic!("Got to backend with non-structure type in structure construction?!");
+                };
+
+                unimplemented!()
+            }
+
+            Expression::FieldRef(_, _, struct_type, val, field) => {
+                let (structure, _) = self.compile_value_or_ref(val, variables, builder)?;
+
+                let Type::Structure(fields) = struct_type else {
+                    panic!("Got to backend with non-structure type in field reference?!");
+                };
+
+                let Some((field_type, offset)) = fields.field_type_and_offset(&field) else {
+                    panic!("Got to backend with invalid field for structure type?!");
+                };
+
+                let field_cranelift_type = self.translate_type(field_type).value_type;
+
+                let value = builder.ins().load(field_cranelift_type, MemFlags::new(), structure, offset);
+                Ok((value, field_cranelift_type))
+            }
 
             Expression::Block(_, _, mut exprs) => match exprs.pop() {
                 None => Ok((builder.ins().iconst(types::I64, 0), VOID_REPR_TYPE)),

src/ir/ast.rs

@@ -113,7 +113,7 @@ pub enum Expression<Type> {
         ArcIntern<String>,
         HashMap<ArcIntern<String>, ValueOrRef<Type>>,
     ),
-    FieldRef(Location, Type, ValueOrRef<Type>, ArcIntern<String>),
+    FieldRef(Location, Type, Type, ValueOrRef<Type>, ArcIntern<String>),
     Block(Location, Type, Vec<Expression<Type>>),
     Print(Location, ValueOrRef<Type>),
     Call(Location, Type, Box<ValueOrRef<Type>>, Vec<ValueOrRef<Type>>),
@@ -129,7 +129,7 @@ impl<Type: Clone + TypeWithVoid> Expression<Type> {
             Expression::Cast(_, t, _) => t.clone(),
             Expression::Primitive(_, t, _, _) => t.clone(),
             Expression::Construct(_, t, _, _) => t.clone(),
-            Expression::FieldRef(_, t, _, _) => t.clone(),
+            Expression::FieldRef(_, t, _, _, _) => t.clone(),
             Expression::Block(_, t, _) => t.clone(),
             Expression::Print(_, _) => Type::void(),
             Expression::Call(_, t, _, _) => t.clone(),
@@ -145,7 +145,7 @@ impl<Type: Clone + TypeWithVoid> Expression<Type> {
             Expression::Cast(l, _, _) => l,
             Expression::Primitive(l, _, _, _) => l,
             Expression::Construct(l, _, _, _) => l,
-            Expression::FieldRef(l, _, _, _) => l,
+            Expression::FieldRef(l, _, _, _, _) => l,
             Expression::Block(l, _, _) => l,
             Expression::Print(l, _) => l,
             Expression::Call(l, _, _, _) => l,

src/ir/eval.rs

@@ -91,7 +91,7 @@ where
                 Ok(Value::Structure(Some(name.clone()), result_fields))
             }
 
-            Expression::FieldRef(loc, _, valref, field) => match valref.eval(env)? {
+            Expression::FieldRef(loc, _, _, valref, field) => match valref.eval(env)? {
                 Value::Structure(oname, mut fields) => match fields.remove(field) {
                     None => Err(EvalError::NoFieldForValue(
                         loc.clone(),

src/ir/fields.rs

@@ -119,6 +119,20 @@ impl<T> Fields<T> {
             cranelift_description
         })
     }
+
+    pub fn field_type_and_offset(&self, field: &ArcIntern<String>) -> Option<(&T, i32)> {
+        let mut offset = 0;
+
+        for (current, ty) in self.fields.iter() {
+            if current == field {
+                return Some((ty, offset));
+            }
+
+            offset += 8;
+        }
+
+        None
+    }
 }
 
 impl<T> IntoIterator for Fields<T> {

src/ir/pretty.rs

@@ -73,7 +73,7 @@ impl Expression<Type> {
                     .braces();
                 allocator.text(name.to_string()).append(inner)
             }
-            Expression::FieldRef(_, _, val, field) => val.pretty(allocator).append(
+            Expression::FieldRef(_, _, _, val, field) => val.pretty(allocator).append(
                 allocator
                     .text(".")
                     .append(allocator.text(field.to_string())),

src/type_infer/convert.rs

@@ -338,6 +338,7 @@ fn convert_expression(
             let result = ir::Expression::FieldRef(
                 loc.clone(),
                 result_type.clone(),
+                etype.clone(),
                 val_or_ref,
                 field.clone().intern(),
             );

src/type_infer/finalize.rs

@@ -73,9 +73,10 @@ fn finalize_expression(
                 .collect(),
         ),
 
-        Expression::FieldRef(loc, ty, valref, field) => Expression::FieldRef(
+        Expression::FieldRef(loc, ty, struct_type, valref, field) => Expression::FieldRef(
             loc,
             finalize_type(ty, resolutions),
+            finalize_type(struct_type, resolutions),
             finalize_val_or_ref(valref, resolutions),
             field,
         ),