From 1d1ed76969174e948dd6e8bccc4cb91678937d5f Mon Sep 17 00:00:00 2001
From: lionarius <git@lionarius.ru>
Date: Fri, 22 Nov 2024 11:04:41 +0300
Subject: [PATCH] ..

---
 src/ast/optimization.rs | 8 ++++++++
 src/ast/typed.rs        | 7 +++++--
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/ast/optimization.rs b/src/ast/optimization.rs
index b269d5d..f1a269a 100644
--- a/src/ast/optimization.rs
+++ b/src/ast/optimization.rs
@@ -21,6 +21,10 @@ pub fn optimize_expr(expr: TypedExpr) -> TypedExpr {
 }
 
 pub fn bubble_binop_vars(expr: TypedExpr) -> TypedExpr {
+    if expr.is_const() {
+        return expr;
+    }
+
     let expr = reorder_commutative_expr(expr);
 
     let expr = match expr {
@@ -138,6 +142,10 @@ fn optimize_special_cases(lhs: TypedExpr, op: BinOp, rhs: TypedExpr) -> TypedExp
             lhs
         },
 
+        // Subtraction by zero
+        (lhs, TypedExpr::Int { value: 0, .. }) if matches!(op, BinOp::Sub) => lhs,
+        (lhs, TypedExpr::Float { value: 0.0, .. }) if matches!(op, BinOp::Sub) => lhs,
+
         // Multiplication/Division by one
         (lhs, TypedExpr::Int { value: 1, .. }) if matches!(op, BinOp::Mul | BinOp::Div) => lhs,
         (lhs, TypedExpr::Float { value: 1.0, .. }) if matches!(op, BinOp::Mul | BinOp::Div) => lhs,
diff --git a/src/ast/typed.rs b/src/ast/typed.rs
index ae6d4a7..a9bcfa4 100644
--- a/src/ast/typed.rs
+++ b/src/ast/typed.rs
@@ -78,8 +78,11 @@ impl fmt::Display for Type {
 
 impl TypedExpr {
     pub fn cast_to_float(self) -> TypedExpr {
-        Self::IntToFloat {
-            value: Box::new(self),
+        match self {
+            Self::IntToFloat { .. } | Self::Float { .. } => self,
+            _ => Self::IntToFloat {
+                value: Box::new(self),
+            },
         }
     }