message: Implement target optimization for IndexGet
diff: @@ -21,8 +21,7 @@ impl Assemble for ast::Path {
  if let Needs::Value = needs {
  if let Some(local) = named.as_local() {
  if let Some(var) = c.scopes.try_get_var(local, c.source_id, c.visitor, span)? {
  - var.copy(&mut c.asm, span, format!("var `{}`", local));
  - return Ok(Asm::top(span));
  + return Ok(Asm::var(span, *var, local.into()));
  }
  }
  }
  