target/riscv: zfh: half-precision computational

Signed-off-by: Kito Cheng <kito.cheng@sifive.com>
Signed-off-by: Chih-Min Chao <chihmin.chao@sifive.com>
Signed-off-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20211210074329.5775-3-frank.chang@sifive.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/target/riscv/internals.h b/target/riscv/internals.h
index b15ad394bb..bce91da11a 100644
--- a/target/riscv/internals.h
+++ b/target/riscv/internals.h
@@ -58,4 +58,20 @@ static inline float32 check_nanbox_s(uint64_t f)
     }
 }
 
+static inline uint64_t nanbox_h(float16 f)
+{
+    return f | MAKE_64BIT_MASK(16, 48);
+}
+
+static inline float16 check_nanbox_h(uint64_t f)
+{
+    uint64_t mask = MAKE_64BIT_MASK(16, 48);
+
+    if (likely((f & mask) == mask)) {
+        return (uint16_t)f;
+    } else {
+        return 0x7E00u; /* default qnan */
+    }
+}
+
 #endif