From 5d2fffbfa09ed071652b0de57c94a2992ed23e5a Mon Sep 17 00:00:00 2001
From: Zhou Fang <33002388+zhou-w-fang@users.noreply.github.com>
Date: Thu, 24 Oct 2024 22:38:37 -0700
Subject: [PATCH] fix: target-source in pop_cnt()

---
 crates/interpreter/src/valid.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/crates/interpreter/src/valid.rs b/crates/interpreter/src/valid.rs
index be814b4b..20b54636 100644
--- a/crates/interpreter/src/valid.rs
+++ b/crates/interpreter/src/valid.rs
@@ -459,9 +459,9 @@ impl SideTable {
     fn pop_cnt(source: SideTableBranch, target: SideTableBranch) -> MResult<u32, Check> {
         let source = source.stack;
         let target = target.stack;
-        let Some(delta) = source.checked_sub(target) else {
+        let Some(delta) = target.checked_sub(source) else {
             #[cfg(feature = "debug")]
-            eprintln!("side-table negative stack delta {source} < {target}");
+            eprintln!("side-table negative stack delta {target} < {source}");
             return Err(unsupported(if_debug!(Unsupported::SideTable)));
         };
         u32::try_from(delta).map_err(|_| {