summaryrefslogtreecommitdiff
path: root/src/math/erfl.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/math/erfl.c')
-rw-r--r--src/math/erfl.c37
1 files changed, 14 insertions, 23 deletions
diff --git a/src/math/erfl.c b/src/math/erfl.c
index 2fd3c440..42bb1a17 100644
--- a/src/math/erfl.c
+++ b/src/math/erfl.c
@@ -253,8 +253,8 @@ static long double erfc1(long double x)
static long double erfc2(uint32_t ix, long double x)
{
+ union ldshape u;
long double s,z,R,S;
- uint32_t i0,i1;
if (ix < 0x3fffa000) /* 0.84375 <= |x| < 1.25 */
return erfc1(x);
@@ -288,28 +288,22 @@ static long double erfc2(uint32_t ix, long double x)
S = sc[0] + s * (sc[1] + s * (sc[2] + s * (sc[3] +
s * (sc[4] + s))));
}
- z = x;
- GET_LDOUBLE_WORDS(ix, i0, i1, z);
- i1 = 0;
- i0 &= 0xffffff00;
- SET_LDOUBLE_WORDS(z, ix, i0, i1);
+ u.f = x;
+ u.i.m &= -1ULL << 40;
+ z = u.f;
return expl(-z*z - 0.5625) * expl((z - x) * (z + x) + R / S) / x;
}
long double erfl(long double x)
{
long double r, s, z, y;
- uint32_t i0, i1, ix;
- int sign;
+ union ldshape u = {x};
+ uint32_t ix = (u.i.se & 0x7fffU)<<16 | u.i.m>>48;
+ int sign = u.i.se >> 15;
- GET_LDOUBLE_WORDS(ix, i0, i1, x);
- sign = ix >> 15;
- ix &= 0x7fff;
- if (ix == 0x7fff) {
+ if (ix >= 0x7fff0000)
/* erf(nan)=nan, erf(+-inf)=+-1 */
return 1 - 2*sign + 1/x;
- }
- ix = (ix << 16) | (i0 >> 16);
if (ix < 0x3ffed800) { /* |x| < 0.84375 */
if (ix < 0x3fde8000) { /* |x| < 2**-33 */
return 0.125 * (8 * x + efx8 * x); /* avoid underflow */
@@ -332,17 +326,13 @@ long double erfl(long double x)
long double erfcl(long double x)
{
long double r, s, z, y;
- uint32_t i0, i1, ix;
- int sign;
+ union ldshape u = {x};
+ uint32_t ix = (u.i.se & 0x7fffU)<<16 | u.i.m>>48;
+ int sign = u.i.se >> 15;
- GET_LDOUBLE_WORDS(ix, i0, i1, x);
- sign = ix>>15;
- ix &= 0x7fff;
- if (ix == 0x7fff)
+ if (ix >= 0x7fff0000)
/* erfc(nan) = nan, erfc(+-inf) = 0,2 */
return 2*sign + 1/x;
-
- ix = (ix << 16) | (i0 >> 16);
if (ix < 0x3ffed800) { /* |x| < 0.84375 */
if (ix < 0x3fbe0000) /* |x| < 2**-65 */
return 1.0 - x;
@@ -358,6 +348,7 @@ long double erfcl(long double x)
}
if (ix < 0x4005d600) /* |x| < 107 */
return sign ? 2 - erfc2(ix,x) : erfc2(ix,x);
- return sign ? 2 - 0x1p-16382L : 0x1p-16382L*0x1p-16382L;
+ y = 0x1p-16382L;
+ return sign ? 2 - y : y*y;
}
#endif