@@ -1863,7 +1863,7 @@ const NO_CACHE = /** @type {EXPECTED_ANY} */ (null);
 // by char compare, overwritten on collision. Shared across parses — hits are
 // content-checked, so a stale entry is merely a miss. Only words short enough
 // to be flat V8 strings (never slices retaining their whole source) are stored.
-const WORD_CACHE_MASK = 0x1fff;
+const WORD_CACHE_MASK = 0xfff;
 /** @type {(string | null)[]} */
 let WORD_CACHE = NO_CACHE;
 const WORD_CACHE_MAX_LEN = 12;
@@ -1886,7 +1886,7 @@ let nextWordLookupsId = 1;
 // too, so serving them from one shared string cuts both allocation churn and
 // retained AST strings. Same rules as WORD_CACHE: content-checked hits, only
 // lengths V8 stores flat (never slices retaining the source).
-const SLICE_CACHE_MASK = 0x1fff;
+const SLICE_CACHE_MASK = 0xfff;
 /** @type {(string | null)[]} */
 let SLICE_CACHE = NO_CACHE;
 const SLICE_CACHE_MAX_LEN = 12;