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-rw-r--r--src/math/lgammal.c45
1 files changed, 17 insertions, 28 deletions
diff --git a/src/math/lgammal.c b/src/math/lgammal.c
index 56d7866d..5d56358e 100644
--- a/src/math/lgammal.c
+++ b/src/math/lgammal.c
@@ -202,13 +202,11 @@ w7 = 4.885026142432270781165E-3L;
static long double sin_pi(long double x)
{
+ union ldshape u = {x};
+ uint32_t ix = (u.i.se & 0x7fffU)<<16 | u.i.m>>48;
long double y, z;
- int n, ix;
- uint32_t se, i0, i1;
+ int n;
- GET_LDOUBLE_WORDS(se, i0, i1, x);
- ix = se & 0x7fff;
- ix = (ix << 16) | (i0 >> 16);
if (ix < 0x3ffd8000) /* 0.25 */
return sinl(pi * x);
y = -x; /* x is assume negative */
@@ -229,8 +227,8 @@ static long double sin_pi(long double x)
} else {
if (ix < 0x403e8000) /* 2^63 */
z = y + two63; /* exact */
- GET_LDOUBLE_WORDS(se, i0, i1, z);
- n = i1 & 1;
+ u.f = z;
+ n = u.i.m & 1;
y = n;
n <<= 2;
}
@@ -261,33 +259,28 @@ static long double sin_pi(long double x)
long double __lgammal_r(long double x, int *sg) {
long double t, y, z, nadj, p, p1, p2, q, r, w;
- int i, ix;
- uint32_t se, i0, i1;
+ union ldshape u = {x};
+ uint32_t ix = (u.i.se & 0x7fffU)<<16 | u.i.m>>48;
+ int sign = u.i.se >> 15;
+ int i;
*sg = 1;
- GET_LDOUBLE_WORDS(se, i0, i1, x);
- ix = se & 0x7fff;
-
- if ((ix | i0 | i1) == 0) {
- if (se & 0x8000)
- *sg = -1;
- return 1.0 / fabsl(x);
- }
-
- ix = (ix << 16) | (i0 >> 16);
/* purge off +-inf, NaN, +-0, and negative arguments */
if (ix >= 0x7fff0000)
return x * x;
-
+ if (x == 0) {
+ *sg -= 2*sign;
+ return 1.0 / fabsl(x);
+ }
if (ix < 0x3fc08000) { /* |x|<2**-63, return -log(|x|) */
- if (se & 0x8000) {
+ if (sign) {
*sg = -1;
return -logl(-x);
}
return -logl(x);
}
- if (se & 0x8000) {
+ if (sign) {
t = sin_pi (x);
if (t == 0.0)
return 1.0 / fabsl(t); /* -integer */
@@ -297,11 +290,7 @@ long double __lgammal_r(long double x, int *sg) {
x = -x;
}
- /* purge off 1 and 2 */
- if ((((ix - 0x3fff8000) | i0 | i1) == 0) ||
- (((ix - 0x40008000) | i0 | i1) == 0))
- r = 0;
- else if (ix < 0x40008000) { /* x < 2.0 */
+ if (ix < 0x40008000) { /* x < 2.0 */
if (ix <= 0x3ffee666) { /* 8.99993896484375e-1 */
/* lgamma(x) = lgamma(x+1) - log(x) */
r = -logl(x);
@@ -380,7 +369,7 @@ long double __lgammal_r(long double x, int *sg) {
r = (x - 0.5) * (t - 1.0) + w;
} else /* 2**66 <= x <= inf */
r = x * (logl(x) - 1.0);
- if (se & 0x8000)
+ if (sign)
r = nadj - r;
return r;
}