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authorSiddhesh Poyarekar <siddhesh@sourceware.org>2016-09-30 05:19:05 +0530
committerSiddhesh Poyarekar <siddhesh@sourceware.org>2016-09-30 05:19:05 +0530
commit2bf499708daebd9ebb59a6d938a372c7f0ca4dce (patch)
tree4dbc3223026cac8c900817f52a41364af62ff631
parent3459931a1aed87b78a521b0eb931a465c1d101b2 (diff)
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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.
-rw-r--r--ChangeLog11
-rw-r--r--sysdeps/ieee754/dbl-64/s_sin.c26
2 files changed, 24 insertions, 13 deletions
diff --git a/ChangeLog b/ChangeLog
index 7f51edd866..9b0bff1b92 100644
--- 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 fef6780e1d..8764c58a9c 100644
--- 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);
 }