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.

diff --git a/ChangeLog b/ChangeLog
index 7f51edd..9b0bff1 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -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.

diff --git a/sysdeps/ieee754/dbl-64/s_sin.c b/sysdeps/ieee754/dbl-64/s_sin.c
index fef6780..8764c58 100644 (file)
--- a/sysdeps/ieee754/dbl-64/s_sin.c
+++ b/sysdeps/ieee754/dbl-64/s_sin.c
@@ -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);
 }