math: use fnstsw consistently instead of fstsw in x87 asm

[musl] / src / math / __fpclassifyl.c

diff --git a/src/math/__fpclassifyl.c b/src/math/__fpclassifyl.c
index 6365c58..c274229 100644 (file)
--- a/src/math/__fpclassifyl.c
+++ b/src/math/__fpclassifyl.c
@@ -1,15 +1,20 @@
 #include "libm.h"
 
 #if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
-
+int __fpclassifyl(long double x)
+{
+       return __fpclassify(x);
+}
 #elif LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384
-/* invalid representations (top bit of u.i.m is wrong) are not handled */
 int __fpclassifyl(long double x)
 {
        union ldshape u = {x};
        int e = u.i.se & 0x7fff;
-       if (!e)
+       int msb = u.i.m>>63;
+       if (!e && !msb)
                return u.i.m ? FP_SUBNORMAL : FP_ZERO;
+       if (!msb)
+               return FP_NAN;
        if (e == 0x7fff)
                return u.i.m << 1 ? FP_NAN : FP_INFINITE;
        return FP_NORMAL;