remove naive interpreter

rust2/src/opts.rs

@@ -0,0 +1,33 @@
+use crate::parse::Instr;
+use bumpalo::Bump;
+
+pub type Ir<'ir> = Vec<IrInstr<'ir>, &'ir Bump>;
+
+pub enum IrInstr<'ir> {
+    Add(u8),
+    Sub(u8),
+    Right(usize),
+    Left(usize),
+    Loop(Ir<'ir>),
+    Out,
+    In,
+    SetNull,
+}
+
+pub fn optimize<'ir>(alloc: &'ir Bump, instrs: &[Instr<'_>]) -> Ir<'ir> {
+    ast_to_ir(alloc, instrs)
+}
+
+fn ast_to_ir<'ir>(alloc: &'ir Bump, ast: &[Instr<'_>]) -> Ir<'ir> {
+    let mut vec = Vec::new_in(alloc);
+    vec.extend(ast.iter().map(|instr| match instr {
+        Instr::Add => IrInstr::Add(1),
+        Instr::Sub => IrInstr::Sub(1),
+        Instr::Right => IrInstr::Right(1),
+        Instr::Left => IrInstr::Left(1),
+        Instr::Out => IrInstr::Out,
+        Instr::In => IrInstr::In,
+        Instr::Loop(body) => IrInstr::Loop(ast_to_ir(alloc, body)),
+    }));
+    vec
+}