1 files changed, 13 insertions, 3 deletions
diff --git a/target/riscv/internals.h b/target/riscv/internals.h
index 6237bb3115..dbb322bfa7 100644
--- a/target/riscv/internals.h
+++ b/target/riscv/internals.h
@@ -72,13 +72,23 @@ static inline float32 check_nanbox_s(CPURISCVState *env, uint64_t f)
     }
 }
 
-static inline uint64_t nanbox_h(float16 f)
+static inline uint64_t nanbox_h(CPURISCVState *env, float16 f)
 {
-    return f | MAKE_64BIT_MASK(16, 48);
+    /* the value is sign-extended instead of NaN-boxing for zfinx */
+    if (RISCV_CPU(env_cpu(env))->cfg.ext_zfinx) {
+        return (int16_t)f;
+    } else {
+        return f | MAKE_64BIT_MASK(16, 48);
+    }
 }
 
-static inline float16 check_nanbox_h(uint64_t f)
+static inline float16 check_nanbox_h(CPURISCVState *env, uint64_t f)
 {
+    /* Disable nanbox check when enable zfinx */
+    if (RISCV_CPU(env_cpu(env))->cfg.ext_zfinx) {
+        return (uint16_t)f;
+    }
+
     uint64_t mask = MAKE_64BIT_MASK(16, 48);
 
     if (likely((f & mask) == mask)) {