diff --git a/target-arm/translate-a64.c b/target-arm/translate-a64.c
index 188287d031..d86b8ffa55 100644
--- a/target-arm/translate-a64.c
+++ b/target-arm/translate-a64.c
@@ -7708,7 +7708,7 @@ static void disas_simd_scalar_two_reg_misc(DisasContext *s, uint32_t insn)
         }
         break;
     case 0x12: /* SQXTUN */
-        if (u) {
+        if (!u) {
             unallocated_encoding(s);
             return;
         }