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-rw-r--r--src/math/asinl.c44
1 files changed, 22 insertions, 22 deletions
diff --git a/src/math/asinl.c b/src/math/asinl.c
index 8799341d..347c5356 100644
--- a/src/math/asinl.c
+++ b/src/math/asinl.c
@@ -23,27 +23,29 @@ long double asinl(long double x)
}
#elif (LDBL_MANT_DIG == 64 || LDBL_MANT_DIG == 113) && LDBL_MAX_EXP == 16384
#include "__invtrigl.h"
-/* 0.95 */
-#define THRESH ((0xe666666666666666ULL>>(64-(LDBL_MANH_SIZE-1)))|LDBL_NBIT)
+#if LDBL_MANT_DIG == 64
+#define CLOSETO1(u) (u.i.m>>56 >= 0xf7)
+#define CLEARBOTTOM(u) (u.i.m &= -1ULL << 32)
+#elif LDBL_MANT_DIG == 113
+#define CLOSETO1(u) (u.i.top >= 0xee00)
+#define CLEARBOTTOM(u) (u.i.lo = 0)
+#endif
long double asinl(long double x)
{
- union IEEEl2bits u;
- long double z,r,s;
- uint16_t expsign, expt;
+ union ldshape u = {x};
+ long double z, r, s;
+ uint16_t e = u.i.se & 0x7fff;
+ int sign = u.i.se >> 15;
- u.e = x;
- expsign = u.xbits.expsign;
- expt = expsign & 0x7fff;
- if (expt >= 0x3fff) { /* |x| >= 1 or nan */
- if (expt == 0x3fff &&
- ((u.bits.manh&~LDBL_NBIT)|u.bits.manl) == 0)
- /* asin(+-1)=+-pi/2 with inexact */
+ if (e >= 0x3fff) { /* |x| >= 1 or nan */
+ /* asin(+-1)=+-pi/2 with inexact */
+ if (x == 1 || x == -1)
return x*pio2_hi + 0x1p-120f;
return 0/(x-x);
}
- if (expt < 0x3fff - 1) { /* |x| < 0.5 */
- if (expt < 0x3fff - 32) { /* |x|<0x1p-32, asinl(x)=x */
+ if (e < 0x3fff - 1) { /* |x| < 0.5 */
+ if (e < 0x3fff - (LDBL_MANT_DIG+1)/2) {
/* return x with inexact if x!=0 */
FORCE_EVAL(x + 0x1p120f);
return x;
@@ -54,18 +56,16 @@ long double asinl(long double x)
z = (1.0 - fabsl(x))*0.5;
s = sqrtl(z);
r = __invtrigl_R(z);
- if (u.bits.manh >= THRESH) { /* if |x| is close to 1 */
+ if (CLOSETO1(u)) {
x = pio2_hi - (2*(s+s*r)-pio2_lo);
} else {
long double f, c;
- u.e = s;
- u.bits.manl = 0;
- f = u.e;
- c = (z-f*f)/(s+f);
+ u.f = s;
+ CLEARBOTTOM(u);
+ f = u.f;
+ c = (z - f*f)/(s + f);
x = 0.5*pio2_hi-(2*s*r - (pio2_lo-2*c) - (0.5*pio2_hi-2*f));
}
- if (expsign>>15)
- return -x;
- return x;
+ return sign ? -x : x;
}
#endif