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ensure that thread dtv pointer is never null to optimize __tls_get_addr
[musl]
/
src
/
math
/
log2l.c
diff --git
a/src/math/log2l.c
b/src/math/log2l.c
index
4339c03
..
345b395
100644
(file)
--- a/
src/math/log2l.c
+++ b/
src/math/log2l.c
@@
-50,11
+50,6
@@
* In the tests over the interval exp(+-10000), the logarithms
* of the random arguments were uniformly distributed over
* [-10000, +10000].
* In the tests over the interval exp(+-10000), the logarithms
* of the random arguments were uniformly distributed over
* [-10000, +10000].
- *
- * ERROR MESSAGES:
- *
- * log singularity: x = 0; returns -INFINITY
- * log domain: x < 0; returns NAN
*/
#include "libm.h"
*/
#include "libm.h"
@@
-113,18
+108,17
@@
static const long double S[4] = {
long double log2l(long double x)
{
long double log2l(long double x)
{
- volatile long double z;
- long double y;
+ long double y, z;
int e;
if (isnan(x))
return x;
if (x == INFINITY)
return x;
int e;
if (isnan(x))
return x;
if (x == INFINITY)
return x;
- if (x <= 0.0
L
) {
- if (x == 0.0
L
)
- return -
INFINITY;
- return
NAN;
+ if (x <= 0.0) {
+ if (x == 0.0)
+ return -
1/(x+0); /* -inf with divbyzero */
+ return
0/0.0f; /* nan with invalid */
}
/* separate mantissa from exponent */
}
/* separate mantissa from exponent */
@@
-139,12
+133,12
@@
long double log2l(long double x)
if (e > 2 || e < -2) {
if (x < SQRTH) { /* 2(2x-1)/(2x+1) */
e -= 1;
if (e > 2 || e < -2) {
if (x < SQRTH) { /* 2(2x-1)/(2x+1) */
e -= 1;
- z = x - 0.5
L
;
- y = 0.5
L * z + 0.5L
;
+ z = x - 0.5;
+ y = 0.5
* z + 0.5
;
} else { /* 2 (x-1)/(x+1) */
} else { /* 2 (x-1)/(x+1) */
- z = x - 0.5
L
;
- z -= 0.5
L
;
- y = 0.5
L * x + 0.5L
;
+ z = x - 0.5;
+ z -= 0.5;
+ y = 0.5
* x + 0.5
;
}
x = z / y;
z = x*x;
}
x = z / y;
z = x*x;
@@
-155,13
+149,13
@@
long double log2l(long double x)
/* logarithm using log(1+x) = x - .5x**2 + x**3 P(x)/Q(x) */
if (x < SQRTH) {
e -= 1;
/* logarithm using log(1+x) = x - .5x**2 + x**3 P(x)/Q(x) */
if (x < SQRTH) {
e -= 1;
- x =
ldexpl(x, 1) - 1.0L; /* 2x - 1 */
+ x =
2.0*x - 1.0;
} else {
} else {
- x = x - 1.0
L
;
+ x = x - 1.0;
}
z = x*x;
y = x * (z * __polevll(x, P, 6) / __p1evll(x, Q, 7));
}
z = x*x;
y = x * (z * __polevll(x, P, 6) / __p1evll(x, Q, 7));
- y = y -
ldexpl(z, -1); /* -0.5x^2 + ... */
+ y = y -
0.5*z;
done:
/* Multiply log of fraction by log2(e)
done:
/* Multiply log of fraction by log2(e)