diff --git a/crates/interpreter/src/side_table.rs b/crates/interpreter/src/side_table.rs
index dc65d365..c491f5d3 100644
--- a/crates/interpreter/src/side_table.rs
+++ b/crates/interpreter/src/side_table.rs
@@ -32,9 +32,9 @@ pub struct SideTableEntryView {
 
 impl SideTableEntry {
     const DELTA_IP_MASK: u64 = 0xffff;
-    const DELTA_STP_MASK: u64 = 0xffff << 16;
-    const VAL_CNT_MASK: u64 = 0xffff << 32;
-    const POP_CNT_MASK: u64 = 0xffff << 48;
+    const DELTA_STP_MASK: u64 = 0x7fff << 16;
+    const VAL_CNT_MASK: u64 = 0x3 << 31;
+    const POP_CNT_MASK: u64 = 0x3 << 33;
 
     pub fn new(view: SideTableEntryView) -> Result<Self, Error> {
         let mut fields = 0;