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Consolidate range reduction in sincos for x > 281474976710656 

Range reduction needs to be done only once for sin and cos, so copy
over all of the relevant functions (__sin, __cos, reduce_and_compute)
and consolidate common code.
This commit is contained in:
Siddhesh Poyarekar 2015-12-21 10:40:32 +05:30
parent 760c2eb7da
commit a045832deb
3 changed files with 66 additions and 2 deletions
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9
ChangeLog
View File

@ -1,3 +1,12 @@
2015-12-21 Siddhesh Poyarekar <siddhesh.poyarekar@linaro.org>
* sysdeps/ieee754/dbl-64/s_sin.c (__sin) [!IN_SINCOS]: Skip
common code for sincos.
(__cos) [!IN_SINCOS]: Likewise.
* sysdeps/ieee754/dbl-64/s_sincos.c (reduce_and_compute_sincos):
New function.
(__sincos): Use it.
2015-12-20 Aurelien Jarno <aurelien@aurel32.net>
* sysdeps/i386/fpu/libm-test-ulps: Move to ....

4
sysdeps/ieee754/dbl-64/s_sin.c
View File

@ -497,6 +497,7 @@ __sin (double x)
}
} /* else if (k < 0x42F00000 ) */
#ifndef IN_SINCOS
/* -----------------281474976710656 <|x| <2^1024----------------------------*/
else if (k < 0x7ff00000)
retval = reduce_and_compute (x, 0);
@ -508,6 +509,7 @@ __sin (double x)
__set_errno (EDOM);
retval = x / x;
}
#endif
return retval;
}
@ -729,6 +731,7 @@ __cos (double x)
}
} /* else if (k < 0x42F00000 ) */
#ifndef IN_SINCOS
/* 281474976710656 <|x| <2^1024 */
else if (k < 0x7ff00000)
retval = reduce_and_compute (x, 1);
@ -739,6 +742,7 @@ __cos (double x)
__set_errno (EDOM);
retval = x / x; /* |x| > 2^1024 */
}
#endif
return retval;
}

55
sysdeps/ieee754/dbl-64/s_sincos.c
View File

@ -27,13 +27,64 @@
#define IN_SINCOS 1
#include "s_sin.c"
/* Consolidated version of reduce_and_compute in s_sin.c that does range
reduction only once and computes sin and cos together. */
static inline void
__always_inline
reduce_and_compute_sincos (double x, double *sinx, double *cosx)
{
double a, da;
unsigned int n = __branred (x, &a, &da);
n = n & 3;
if (n == 1 || n == 2)
{
a = -a;
da = -da;
}
if (n & 1)
{
double *temp = cosx;
cosx = sinx;
sinx = temp;
}
if (a * a < 0.01588)
*sinx = bsloww (a, da, x, n);
else
*sinx = bsloww1 (a, da, x, n);
*cosx = bsloww2 (a, da, x, n);
}
void
__sincos (double x, double *sinx, double *cosx)
{
mynumber u;
int k;
SET_RESTORE_ROUND_53BIT (FE_TONEAREST);
*sinx = __sin (x);
*cosx = __cos (x);
u.x = x;
k = 0x7fffffff & u.i[HIGH_HALF];
if (k < 0x42F00000)
{
*sinx = __sin_local (x);
*cosx = __cos_local (x);
return;
}
if (k < 0x7ff00000)
{
reduce_and_compute_sincos (x, sinx, cosx);
return;
}
if (isinf (x))
__set_errno (EDOM);
*sinx = *cosx = x / x;
}
weak_alias (__sincos, sincos)
#ifdef NO_LONG_DOUBLE