Fixed typo.

ykcompile/src/lib.rs

@@ -96,7 +96,7 @@ pub struct TraceCompiler {
     available_regs: Vec<u8>,
     /// Maps locals to their assigned registers.
     assigned_regs: HashMap<Local, u8>,
-    /// Stores the destination local of the outer most function and moves its content into RAX at
+    /// Stores the destination local of the outermost function and moves its content into RAX at
     /// the end of the trace.
     rtn_var: Option<Place>,
 }