feat: 支持复合运算符

crates/oxide_compiler/src/counter.rs

@@ -223,7 +223,7 @@ impl Compiler {
                 } else {
                     self.count_expression(&assign.right, ctx);
                     ctx.alloc_reg();
-                    ctx.projected_pc += 1; // STORE_VAR
+                    ctx.projected_pc += 1;
                 }
             }
             Expression::ConditionalExpression(cond) => {

crates/oxide_compiler/src/emitter.rs

@@ -630,13 +630,27 @@ impl Compiler {
                     &assign.left
                 {
                     if assign.operator != AssignmentOperator::Assign {
-                        return Err("compound assignment not yet supported".into());
+                        let rhs = self.emit_expression(&assign.right, ctx)?;
+                        let name = id_ref.name.as_str();
+                        let var_reg = ctx.lookup_or_global(name);
+                        let op = match assign.operator {
+                            AssignmentOperator::Addition => OpCode::COMPOUND_ADD,
+                            AssignmentOperator::Subtraction => OpCode::COMPOUND_SUB,
+                            AssignmentOperator::Multiplication => OpCode::COMPOUND_MUL,
+                            AssignmentOperator::Division => OpCode::COMPOUND_DIV,
+                            AssignmentOperator::Remainder => OpCode::COMPOUND_MOD,
+                            AssignmentOperator::Exponential => OpCode::COMPOUND_EXP,
+                            _ => unreachable!(),
+                        };
+                        ctx.emit(opcode::encode(op, var_reg, rhs, 0));
+                        Ok(var_reg)
+                    } else {
+                        let val_reg = self.emit_expression(&assign.right, ctx)?;
+                        let name = id_ref.name.as_str();
+                        let var_reg = ctx.lookup_or_global(name);
+                        ctx.emit(opcode::encode(OpCode::STORE_VAR, var_reg, val_reg, 0));
+                        Ok(val_reg)
                     }
-                    let val_reg = self.emit_expression(&assign.right, ctx)?;
-                    let name = id_ref.name.as_str();
-                    let var_reg = ctx.lookup_or_global(name);
-                    ctx.emit(opcode::encode(OpCode::STORE_VAR, var_reg, val_reg, 0));
-                    Ok(val_reg)
                 } else {
                     Err("assignment target not supported".into())
                 }

crates/oxide_compiler/src/hash.rs

@@ -155,6 +155,11 @@ fn hash_expression(expr: &Expression, h: &mut rustc_hash::FxHasher) {
             8u8.hash(h);
             b.value.hash(h);
         }
+        Expression::AssignmentExpression(assign) => {
+            11u8.hash(h);
+            std::mem::discriminant(&assign.operator).hash(h);
+            hash_expression(&assign.right, h);
+        }
         _ => {
             std::mem::discriminant(expr).hash(h);
         }

crates/oxide_compiler/src/opcode.rs

@@ -16,8 +16,14 @@ pub enum OpCode {
     DIV = 0x03,
     MOD = 0x04,
     NEG = 0x05,
+    COMPOUND_ADD = 0x06,
+    COMPOUND_SUB = 0x07,
+    COMPOUND_MUL = 0x08,
+    COMPOUND_DIV = 0x09,
+    COMPOUND_MOD = 0x0A,
+    COMPOUND_EXP = 0x0B,
 
-    // ── Comparison (0x10-0x1F) ──
+    // -- Comparison (0x10-0x1F) --
     EQ = 0x10,
     NEQ = 0x11,
     LT = 0x12,
@@ -104,6 +110,12 @@ impl TryFrom<u8> for OpCode {
             0x03 => Ok(OpCode::DIV),
             0x04 => Ok(OpCode::MOD),
             0x05 => Ok(OpCode::NEG),
+            0x06 => Ok(OpCode::COMPOUND_ADD),
+            0x07 => Ok(OpCode::COMPOUND_SUB),
+            0x08 => Ok(OpCode::COMPOUND_MUL),
+            0x09 => Ok(OpCode::COMPOUND_DIV),
+            0x0A => Ok(OpCode::COMPOUND_MOD),
+            0x0B => Ok(OpCode::COMPOUND_EXP),
             0x10 => Ok(OpCode::EQ),
             0x11 => Ok(OpCode::NEQ),
             0x12 => Ok(OpCode::LT),
@@ -163,6 +175,12 @@ impl fmt::Display for OpCode {
             OpCode::DIV => "DIV",
             OpCode::MOD => "MOD",
             OpCode::NEG => "NEG",
+            OpCode::COMPOUND_ADD => "COMPOUND_ADD",
+            OpCode::COMPOUND_SUB => "COMPOUND_SUB",
+            OpCode::COMPOUND_MUL => "COMPOUND_MUL",
+            OpCode::COMPOUND_DIV => "COMPOUND_DIV",
+            OpCode::COMPOUND_MOD => "COMPOUND_MOD",
+            OpCode::COMPOUND_EXP => "COMPOUND_EXP",
             OpCode::EQ => "EQ",
             OpCode::NEQ => "NEQ",
             OpCode::LT => "LT",