softfloat: fix floatx80_is_infinity()

With floatx80, the explicit bit is set for infinity.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

diff --git a/fpu/softfloat.h b/fpu/softfloat.h
index 340f0a9..3363128 100644 (file)
--- a/fpu/softfloat.h
+++ b/fpu/softfloat.h
@@ -566,7 +566,7 @@ INLINE floatx80 floatx80_chs(floatx80 a)
 
 INLINE int floatx80_is_infinity(floatx80 a)
 {
-    return (a.high & 0x7fff) == 0x7fff && a.low == 0;
+    return (a.high & 0x7fff) == 0x7fff && a.low == 0x8000000000000000LL;
 }
 
 INLINE int floatx80_is_neg(floatx80 a)