diff --git a/crates/aarch64/src/lib.rs b/crates/aarch64/src/lib.rs
index 22ee0ac..3feef97 100644
--- a/crates/aarch64/src/lib.rs
+++ b/crates/aarch64/src/lib.rs
@@ -1198,7 +1198,7 @@ fn lower_control_pcode(
                     destination: lower_place(language, output)?,
                     left: lower_value(language, left)?,
                     right: lower_value(language, right)?,
-                    element_size: arguments[0]?,
+                    element_size: neon_comparison_element_size(language, left, arguments[0])?,
                 }),
                 NEON_UNSIGNED_MAXIMUM_ACROSS_USER_OP => {
                     Some(Operation::NeonUnsignedMaximumAcross {
@@ -1225,7 +1225,7 @@ fn lower_control_pcode(
                     destination: lower_place(language, output)?,
                     left: lower_value(language, left)?,
                     right: lower_value(language, right)?,
-                    element_size: arguments[0]?,
+                    element_size: neon_comparison_element_size(language, left, arguments[0])?,
                 }),
                 NEON_BITWISE_INSERT_USER_OP | NEON_BITWISE_INSERT_IF_FALSE_USER_OP => {
                     lower_neon_bitwise_insert_pcode(
@@ -1267,6 +1267,20 @@ fn lower_neon_bitwise_insert_pcode(
     })
 }
 
+fn neon_comparison_element_size(
+    language: &SleighData,
+    left: PcodeValue,
+    explicit: Option<Value>,
+) -> Option<Value> {
+    explicit.or_else(|| {
+        let size = lower_value(language, left)?.size;
+        Some(Value {
+            source: ValueSource::Constant(u128::from(size)),
+            size: 1,
+        })
+    })
+}
+
 fn is_extended_user_op(user_op: &str) -> bool {
     matches!(
         user_op,
@@ -1328,21 +1342,21 @@ fn lower_extended_user_pcode(
             destination: lower_place(language, output)?,
             left: lower_value(language, left)?,
             right: lower_value(language, right)?,
-            element_size: arguments[0]?,
+            element_size: neon_comparison_element_size(language, left, arguments[0])?,
         }),
         NEON_COMPARE_GREATER_THAN_OR_EQUAL_USER_OP => {
             Some(Operation::NeonCompareGreaterThanOrEqual {
                 destination: lower_place(language, output)?,
                 left: lower_value(language, left)?,
                 right: lower_value(language, right)?,
-                element_size: arguments[0]?,
+                element_size: neon_comparison_element_size(language, left, arguments[0])?,
             })
         }
         NEON_COMPARE_GREATER_THAN_USER_OP => Some(Operation::NeonCompareGreaterThan {
             destination: lower_place(language, output)?,
             left: lower_value(language, left)?,
             right: lower_value(language, right)?,
-            element_size: arguments[0]?,
+            element_size: neon_comparison_element_size(language, left, arguments[0])?,
         }),
         NEON_MINIMUM_NUMBER_USER_OP if arguments[0].is_none() => {
             Some(Operation::FloatMinimumNumber {
@@ -3271,6 +3285,11 @@ fn execute_neon_comparison(
             result |= lane_mask << shift;
         }
     }
+    let destination = if destination.size == element_size {
+        scalar_vector_destination(destination).ok_or_else(unsupported)?
+    } else {
+        destination
+    };
     Ok((destination, result))
 }
 
@@ -4778,6 +4797,16 @@ mod tests {
             state.vector(1),
             Some(u128::from(u32::MAX) << 64 | u128::from(u32::MAX))
         );
+
+        let mut memory = executable_memory(&[
+            0x23, 0x34, 0xe2, 0x7e, // cmhi d3, d1, d2
+        ]);
+        let mut state = Aarch64State::new(CODE_ADDRESS, GuestAddress::new(0x8000));
+        state.set_vector(1, 9).unwrap();
+        state.set_vector(2, 8).unwrap();
+        state.set_vector(3, u128::MAX).unwrap();
+        interpreter.step(&mut state, &mut memory).unwrap();
+        assert_eq!(state.vector(3), Some(u128::from(u64::MAX)));
     }
 
     #[test]