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[PATCH 3/4] Use copysign instead of ternary conditions for positive constants
- From: Siddhesh Poyarekar <siddhesh at sourceware dot org>
- To: libc-alpha at sourceware dot org
- Date: Tue, 27 Sep 2016 23:19:12 +0530
- Subject: [PATCH 3/4] Use copysign instead of ternary conditions for positive constants
- Authentication-results: sourceware.org; auth=none
- References: <1474998553-2366-1-git-send-email-siddhesh@sourceware.org>
This is the first very simple substitution of ternary conditions for
correction adjustments with __copysign for positive constants.
* sysdeps/ieee754/dbl-64/s_sin.c (do_cos_slow): use copysign
instead of ternary condition.
(do_sin_slow): Likewise.
(do_sincos_1): Likewise.
(do_sincos_2): Likewise.
(__cos): Likewise.
(sloww): Likewise.
(sloww1): Likewise.
(sloww2): Likewise.
(bsloww): Likewise.
(bsloww1): Likewise.
(bsloww2): Likewise.
---
sysdeps/ieee754/dbl-64/s_sin.c | 38 +++++++++++++++++++-------------------
1 file changed, 19 insertions(+), 19 deletions(-)
diff --git a/sysdeps/ieee754/dbl-64/s_sin.c b/sysdeps/ieee754/dbl-64/s_sin.c
index ea41a7c..e4333a4 100644
--- a/sysdeps/ieee754/dbl-64/s_sin.c
+++ b/sysdeps/ieee754/dbl-64/s_sin.c
@@ -198,7 +198,7 @@ do_cos_slow (double x, double dx, double eps, double *corp)
cor = cor + ((cs - y) - e1 * x1);
res = y + cor;
cor = (y - res) + cor;
- cor = 1.0005 * cor + ((cor > 0) ? eps : -eps);
+ cor = 1.0005 * cor + __copysign (eps, cor);
*corp = cor;
return res;
}
@@ -258,7 +258,7 @@ do_sin_slow (double x, double dx, double eps, double *corp)
cor = cor + ((sn - y) + c1 * x1);
res = y + cor;
cor = (y - res) + cor;
- cor = 1.0005 * cor + ((cor > 0) ? eps : -eps);
+ cor = 1.0005 * cor + __copysign (eps, cor);
*corp = cor;
return res;
}
@@ -337,13 +337,13 @@ do_sincos_1 (double a, double da, double x, int4 n, int4 k)
{
/* Taylor series. */
res = TAYLOR_SIN (xx, a, da, cor);
- cor = (cor > 0) ? 1.02 * cor + eps : 1.02 * cor - eps;
+ cor = 1.02 * cor + __copysign (eps, cor);
retval = (res == res + cor) ? res : sloww (a, da, x, k);
}
else
{
res = do_sin (a, da, &cor);
- cor = (cor > 0) ? 1.035 * cor + eps : 1.035 * cor - eps;
+ cor = 1.035 * cor + __copysign (eps, cor);
retval = ((res == res + cor) ? ((a > 0) ? res : -res)
: sloww1 (a, da, x, k));
}
@@ -352,7 +352,7 @@ do_sincos_1 (double a, double da, double x, int4 n, int4 k)
case 1:
case 3:
res = do_cos (a, da, &cor);
- cor = (cor > 0) ? 1.025 * cor + eps : 1.025 * cor - eps;
+ cor = 1.025 * cor + __copysign (eps, cor);
retval = ((res == res + cor) ? ((n & 2) ? -res : res)
: sloww2 (a, da, x, n));
break;
@@ -411,13 +411,13 @@ do_sincos_2 (double a, double da, double x, int4 n, int4 k)
{
/* Taylor series. */
res = TAYLOR_SIN (xx, a, da, cor);
- cor = (cor > 0) ? 1.02 * cor + eps : 1.02 * cor - eps;
+ cor = 1.02 * cor + __copysign (eps, cor);
retval = (res == res + cor) ? res : bsloww (a, da, x, n);
}
else
{
res = do_sin (a, da, &cor);
- cor = (cor > 0) ? 1.035 * cor + eps : 1.035 * cor - eps;
+ cor = 1.035 * cor + __copysign (eps, cor);
retval = ((res == res + cor) ? ((a > 0) ? res : -res)
: bsloww1 (a, da, x, n));
}
@@ -426,7 +426,7 @@ do_sincos_2 (double a, double da, double x, int4 n, int4 k)
case 1:
case 3:
res = do_cos (a, da, &cor);
- cor = (cor > 0) ? 1.025 * cor + eps : 1.025 * cor - eps;
+ cor = 1.025 * cor + __copysign (eps, cor);
retval = ((res == res + cor) ? ((n & 2) ? -res : res)
: bsloww2 (a, da, x, n));
break;
@@ -573,13 +573,13 @@ __cos (double x)
if (xx < 0.01588)
{
res = TAYLOR_SIN (xx, a, da, cor);
- cor = (cor > 0) ? 1.02 * cor + 1.0e-31 : 1.02 * cor - 1.0e-31;
+ cor = 1.02 * cor + __copysign (1.0e-31, cor);
retval = (res == res + cor) ? res : sloww (a, da, x, 1);
}
else
{
res = do_sin (a, da, &cor);
- cor = (cor > 0) ? 1.035 * cor + 1.0e-31 : 1.035 * cor - 1.0e-31;
+ cor = 1.035 * cor + __copysign (1.0e-31, cor);
retval = ((res == res + cor) ? ((a > 0) ? res : -res)
: sloww1 (a, da, x, 1));
}
@@ -705,7 +705,7 @@ sloww (double x, double dx, double orig, int k)
double eps = fabs (orig) * 3.1e-30;
- cor = 1.0005 * cor + ((cor > 0) ? eps : -eps);
+ cor = 1.0005 * cor + __copysign (eps, cor);
if (res == res + cor)
return res;
@@ -714,7 +714,7 @@ sloww (double x, double dx, double orig, int k)
da = (x > 0) ? dx : -dx;
__dubsin (a, da, w);
eps = fabs (orig) * 1.1e-30;
- cor = 1.000000001 * w[1] + ((w[1] > 0) ? eps : -eps);
+ cor = 1.000000001 * w[1] + __copysign (eps, w[1]);
if (w[0] == w[0] + cor)
return (x > 0) ? w[0] : -w[0];
@@ -740,7 +740,7 @@ sloww (double x, double dx, double orig, int k)
dx = (a > 0) ? da : -da;
__dubsin (x, dx, w);
eps = fabs (orig) * 1.1e-40;
- cor = 1.000000001 * w[1] + ((w[1] > 0) ? eps : -eps);
+ cor = 1.000000001 * w[1] + __copysign (eps, w[1]);
if (w[0] == w[0] + cor)
return (a > 0) ? w[0] : -w[0];
@@ -770,7 +770,7 @@ sloww1 (double x, double dx, double orig, int k)
__dubsin (fabs (x), dx, w);
double eps = 1.1e-30 * fabs (orig);
- cor = 1.000000005 * w[1] + ((w[1] > 0) ? eps : -eps);
+ cor = 1.000000005 * w[1] + __copysign (eps, w[1]);
if (w[0] == w[0] + cor)
return (x > 0) ? w[0] : -w[0];
@@ -800,7 +800,7 @@ sloww2 (double x, double dx, double orig, int n)
__docos (fabs (x), dx, w);
double eps = 1.1e-30 * fabs (orig);
- cor = 1.000000005 * w[1] + ((w[1] > 0) ? eps : -eps);
+ cor = 1.000000005 * w[1] + __copysign (eps, w[1]);
if (w[0] == w[0] + cor)
return (n & 2) ? -w[0] : w[0];
@@ -823,14 +823,14 @@ bsloww (double x, double dx, double orig, int n)
double res, cor, w[2], a, da;
res = TAYLOR_SLOW (x, dx, cor);
- cor = 1.0005 * cor + ((cor > 0) ? 1.1e-24 : -1.1e-24);
+ cor = 1.0005 * cor + __copysign (1.1e-24, cor);
if (res == res + cor)
return res;
a = fabs (x);
da = (x > 0) ? dx : -dx;
__dubsin (a, da, w);
- cor = 1.000000001 * w[1] + ((w[1] > 0) ? 1.1e-24 : -1.1e-24);
+ cor = 1.000000001 * w[1] + __copysign (1.1e-24, w[1]);
if (w[0] == w[0] + cor)
return (x > 0) ? w[0] : -w[0];
@@ -858,7 +858,7 @@ bsloww1 (double x, double dx, double orig, int n)
dx = (x > 0) ? dx : -dx;
__dubsin (fabs (x), dx, w);
- cor = 1.000000005 * w[1] + ((w[1] > 0) ? 1.1e-24 : -1.1e-24);
+ cor = 1.000000005 * w[1] + __copysign (1.1e-24, w[1]);
if (w[0] == w[0] + cor)
return (x > 0) ? w[0] : -w[0];
@@ -886,7 +886,7 @@ bsloww2 (double x, double dx, double orig, int n)
dx = (x > 0) ? dx : -dx;
__docos (fabs (x), dx, w);
- cor = 1.000000005 * w[1] + ((w[1] > 0) ? 1.1e-24 : -1.1e-24);
+ cor = 1.000000005 * w[1] + __copysign (1.1e-24, w[1]);
if (w[0] == w[0] + cor)
return (n & 2) ? -w[0] : w[0];
--
2.7.4