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Use copysign instead of ternary for some sin/cos input ranges 

These are remaining cases where we can deduce and conclude that the
sign of the result should be the same as the sign of the input being
checked.  For example, for sin(x), the sign of the result is the same
as the result itself for x < pi.  Likewise, for sine values where x
after range reduction falls into this range and its sign is preserved.

	* sysdeps/ieee754/dbl-64/s_sin.c (do_sincos_1): Use copysign
	instead of ternary condition.
	(do_sincos_2): Likewise.
	(__sin): Likewise.
	(__cos): Likewise.
	(slow): Likewise.
	(sloww): Likewise.
	(sloww1): Likewise.
	(bsloww): Likewise.
	(bsloww1): Likewise.
This commit is contained in:
Siddhesh Poyarekar 2016-09-30 05:19:05 +05:30
parent 3459931a1a
commit 2bf499708d
2 changed files with 24 additions and 13 deletions
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11
ChangeLog
View File

@ -1,5 +1,16 @@
2016-09-29 Siddhesh Poyarekar <siddhesh@sourceware.org>
* sysdeps/ieee754/dbl-64/s_sin.c (do_sincos_1): Use copysign
instead of ternary condition.
(do_sincos_2): Likewise.
(__sin): Likewise.
(__cos): Likewise.
(slow): Likewise.
(sloww): Likewise.
(sloww1): Likewise.
(bsloww): Likewise.
(bsloww1): Likewise.
* sysdeps/ieee754/dbl-64/s_sin.c (do_cos_slow): use copysign
instead of ternary condition.
(do_sin_slow): Likewise.

26
sysdeps/ieee754/dbl-64/s_sin.c
View File

@ -344,7 +344,7 @@ do_sincos_1 (double a, double da, double x, int4 n, int4 k)
{
res = do_sin (a, da, &cor);
cor = 1.035 * cor + __copysign (eps, cor);
retval = ((res == res + cor) ? ((a > 0) ? res : -res)
retval = ((res == res + cor) ? __copysign (res, a)
: sloww1 (a, da, x, k));
}
break;
@ -418,7 +418,7 @@ do_sincos_2 (double a, double da, double x, int4 n, int4 k)
{
res = do_sin (a, da, &cor);
cor = 1.035 * cor + __copysign (eps, cor);
retval = ((res == res + cor) ? ((a > 0) ? res : -res)
retval = ((res == res + cor) ? __copysign (res, a)
: bsloww1 (a, da, x, n));
}
break;
@ -479,7 +479,7 @@ __sin (double x)
{
res = do_sin (x, 0, &cor);
retval = (res == res + 1.096 * cor) ? res : slow1 (x);
retval = m > 0 ? retval : -retval;
retval = __copysign (retval, x);
} /* else if (k < 0x3feb6000) */
/*----------------------- 0.855469 <|x|<2.426265 ----------------------*/
@ -489,7 +489,7 @@ __sin (double x)
t = hp0 - fabs (x);
res = do_cos (t, hp1, &cor);
retval = (res == res + 1.020 * cor) ? res : slow2 (x);
retval = m > 0 ? retval : -retval;
retval = __copysign (retval, x);
} /* else if (k < 0x400368fd) */
#ifndef IN_SINCOS
@ -580,7 +580,7 @@ __cos (double x)
{
res = do_sin (a, da, &cor);
cor = 1.035 * cor + __copysign (1.0e-31, cor);
retval = ((res == res + cor) ? ((a > 0) ? res : -res)
retval = ((res == res + cor) ? __copysign (res, a)
: sloww1 (a, da, x, 1));
}
@ -634,9 +634,9 @@ slow (double x)
__dubsin (fabs (x), 0, w);
if (w[0] == w[0] + 1.000000001 * w[1])
return (x > 0) ? w[0] : -w[0];
return __copysign (w[0], x);
return (x > 0) ? __mpsin (x, 0, false) : -__mpsin (-x, 0, false);
return __copysign (__mpsin (fabs (x), 0, false), x);
}
/*******************************************************************************/
@ -717,7 +717,7 @@ sloww (double x, double dx, double orig, int k)
cor = 1.000000001 * w[1] + __copysign (eps, w[1]);
if (w[0] == w[0] + cor)
return (x > 0) ? w[0] : -w[0];
return __copysign (w[0], x);
t = (orig * hpinv + toint);
xn = t - toint;
@ -743,7 +743,7 @@ sloww (double x, double dx, double orig, int k)
cor = 1.000000001 * w[1] + __copysign (eps, w[1]);
if (w[0] == w[0] + cor)
return (a > 0) ? w[0] : -w[0];
return __copysign (w[0], a);
return k ? __mpcos (orig, 0, true) : __mpsin (orig, 0, true);
}
@ -764,7 +764,7 @@ sloww1 (double x, double dx, double orig, int k)
res = do_sin_slow (x, dx, 3.1e-30 * fabs (orig), &cor);
if (res == res + cor)
return (x > 0) ? res : -res;
return __copysign (res, x);
dx = (x > 0 ? dx : -dx);
__dubsin (fabs (x), dx, w);
@ -773,7 +773,7 @@ sloww1 (double x, double dx, double orig, int k)
cor = 1.000000005 * w[1] + __copysign (eps, w[1]);
if (w[0] == w[0] + cor)
return (x > 0) ? w[0] : -w[0];
return __copysign (w[0], x);
return (k == 1) ? __mpcos (orig, 0, true) : __mpsin (orig, 0, true);
}
@ -833,7 +833,7 @@ bsloww (double x, double dx, double orig, int n)
cor = 1.000000001 * w[1] + __copysign (1.1e-24, w[1]);
if (w[0] == w[0] + cor)
return (x > 0) ? w[0] : -w[0];
return __copysign (w[0], x);
return (n & 1) ? __mpcos (orig, 0, true) : __mpsin (orig, 0, true);
}
@ -861,7 +861,7 @@ bsloww1 (double x, double dx, double orig, int n)
cor = 1.000000005 * w[1] + __copysign (1.1e-24, w[1]);
if (w[0] == w[0] + cor)
return (x > 0) ? w[0] : -w[0];
return __copysign (w[0], x);
return (n & 1) ? __mpcos (orig, 0, true) : __mpsin (orig, 0, true);
}