From 3378f556ec251721f3d2471461d7fe4d9e28d7d5 Mon Sep 17 00:00:00 2001
From: sofia <sofia@teascade.net>
Date: Mon, 21 Jul 2025 21:28:39 +0300
Subject: [PATCH] Add AST -> MIR for typecasting

---
 reid/src/ast/process.rs       | 4 +++-
 reid/src/codegen.rs           | 1 +
 reid/src/mir/fmt.rs           | 1 +
 reid/src/mir/implement.rs     | 9 +++++++++
 reid/src/mir/mod.rs           | 1 +
 reid/src/mir/typecheck.rs     | 1 +
 reid/src/mir/typeinference.rs | 1 +
 7 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/reid/src/ast/process.rs b/reid/src/ast/process.rs
index 58498b0..e8f34d9 100644
--- a/reid/src/ast/process.rs
+++ b/reid/src/ast/process.rs
@@ -256,7 +256,9 @@ impl ast::Expression {
                     Box::new(expr.process(module_id)),
                 ),
             },
-            ast::ExpressionKind::CastTo(expression, _) => todo!(),
+            ast::ExpressionKind::CastTo(expression, ty) => {
+                mir::ExprKind::CastTo(Box::new(expression.process(module_id)), ty.0.clone().into())
+            }
         };
 
         mir::Expression(kind, self.1.as_meta(module_id))
diff --git a/reid/src/codegen.rs b/reid/src/codegen.rs
index 142557f..9df8827 100644
--- a/reid/src/codegen.rs
+++ b/reid/src/codegen.rs
@@ -1028,6 +1028,7 @@ impl mir::Expression {
                     }
                 })
             }
+            mir::ExprKind::CastTo(expression, type_kind) => todo!(),
         };
         if let Some(value) = &value {
             value.instr().maybe_location(&mut scope.block, location);
diff --git a/reid/src/mir/fmt.rs b/reid/src/mir/fmt.rs
index 6e00663..b79ecb1 100644
--- a/reid/src/mir/fmt.rs
+++ b/reid/src/mir/fmt.rs
@@ -211,6 +211,7 @@ impl Display for ExprKind {
             ExprKind::Borrow(var_ref, false) => write!(f, "&{}", var_ref),
             ExprKind::Borrow(var_ref, true) => write!(f, "&mut {}", var_ref),
             ExprKind::Deref(var_ref) => write!(f, "*{}", var_ref),
+            ExprKind::CastTo(expression, type_kind) => write!(f, "{} as {}", expression, type_kind),
         }
     }
 }
diff --git a/reid/src/mir/implement.rs b/reid/src/mir/implement.rs
index aab7ba1..989acc8 100644
--- a/reid/src/mir/implement.rs
+++ b/reid/src/mir/implement.rs
@@ -319,6 +319,13 @@ impl Expression {
                     _ => Err(ReturnTypeOther::DerefNonBorrow(var.2)),
                 }
             }
+            CastTo(expr, type_kind) => match expr.return_type(refs) {
+                Ok(ret_type) => match ret_type {
+                    (ReturnKind::Hard, ty) => Ok((ReturnKind::Hard, ty)),
+                    _ => Ok((ReturnKind::Soft, type_kind.clone())),
+                },
+                Err(_) => Ok((ReturnKind::Soft, type_kind.clone())),
+            },
         }
     }
 
@@ -336,6 +343,7 @@ impl Expression {
             ExprKind::BinOp(_, _, _) => None,
             ExprKind::FunctionCall(_) => None,
             ExprKind::If(_) => None,
+            ExprKind::CastTo(expression, _) => expression.backing_var(),
         }
     }
 
@@ -363,6 +371,7 @@ impl Expression {
             ExprKind::Block(_) => None,
             ExprKind::Borrow(_, _) => None,
             ExprKind::Deref(_) => None,
+            ExprKind::CastTo(expression, _) => expression.num_value(),
         }
     }
 }
diff --git a/reid/src/mir/mod.rs b/reid/src/mir/mod.rs
index 18da67a..b734c7e 100644
--- a/reid/src/mir/mod.rs
+++ b/reid/src/mir/mod.rs
@@ -254,6 +254,7 @@ pub enum ExprKind {
     Block(Block),
     Borrow(NamedVariableRef, bool),
     Deref(NamedVariableRef),
+    CastTo(Box<Expression>, TypeKind),
 }
 
 #[derive(Debug)]
diff --git a/reid/src/mir/typecheck.rs b/reid/src/mir/typecheck.rs
index 630e904..28f4e4a 100644
--- a/reid/src/mir/typecheck.rs
+++ b/reid/src/mir/typecheck.rs
@@ -712,6 +712,7 @@ impl Expression {
 
                 Ok(*inner)
             }
+            ExprKind::CastTo(expression, type_kind) => todo!(),
         }
     }
 }
diff --git a/reid/src/mir/typeinference.rs b/reid/src/mir/typeinference.rs
index efb79d3..580167d 100644
--- a/reid/src/mir/typeinference.rs
+++ b/reid/src/mir/typeinference.rs
@@ -397,6 +397,7 @@ impl Expression {
                     _ => Err(ErrorKind::AttemptedDerefNonBorrow(var.1.clone())),
                 }
             }
+            ExprKind::CastTo(expression, type_kind) => todo!(),
         }
     }
 }