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From: Siddhesh Poyarekar <siddhesh@sourceware.org>
To: libc-alpha@sourceware.org
Subject: [PATCH 1/4] consolidate sign checks for slow2
Date: Tue, 27 Sep 2016 17:49:00 -0000	[thread overview]
Message-ID: <1474998553-2366-2-git-send-email-siddhesh@sourceware.org> (raw)
In-Reply-To: <1474998553-2366-1-git-send-email-siddhesh@sourceware.org>

Simplify the code a bit by consolidating sign checks in slow1 and
slow2 into __sin at the higher level.

Siddhesh

	* sysdeps/ieee754/dbl-64/s_sin.c (slow1): Consolidate sign
	check from here...
	(slow2): ... and here...
	(__sin): ... to here.
---
 sysdeps/ieee754/dbl-64/s_sin.c | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/sysdeps/ieee754/dbl-64/s_sin.c b/sysdeps/ieee754/dbl-64/s_sin.c
index 18f1789..d60feb4 100644
--- a/sysdeps/ieee754/dbl-64/s_sin.c
+++ b/sysdeps/ieee754/dbl-64/s_sin.c
@@ -478,7 +478,8 @@ __sin (double x)
   else if (k < 0x3feb6000)
     {
       res = do_sin (x, 0, &cor);
-      retval = (res == res + 1.096 * cor) ? (m > 0 ? res : -res) : slow1 (x);
+      retval = (res == res + 1.096 * cor) ? res : slow1 (x);
+      retval = m > 0 ? retval : -retval;
     }				/*   else  if (k < 0x3feb6000)    */
 
 /*----------------------- 0.855469  <|x|<2.426265  ----------------------*/
@@ -487,7 +488,8 @@ __sin (double x)
 
       t = hp0 - fabs (x);
       res = do_cos (t, hp1, &cor);
-      retval = (res == res + 1.020 * cor) ? ((m > 0) ? res : -res) : slow2 (x);
+      retval = (res == res + 1.020 * cor) ? res : slow2 (x);
+      retval = m > 0 ? retval : -retval;
     }				/*   else  if (k < 0x400368fd)    */
 
 #ifndef IN_SINCOS
@@ -650,13 +652,13 @@ slow1 (double x)
 
   res = do_sin_slow (x, 0, 0, &cor);
   if (res == res + cor)
-    return (x > 0) ? res : -res;
+    return res;
 
   __dubsin (fabs (x), 0, w);
   if (w[0] == w[0] + 1.000000005 * w[1])
-    return (x > 0) ? w[0] : -w[0];
+    return w[0];
 
-  return (x > 0) ? __mpsin (x, 0, false) : -__mpsin (-x, 0, false);
+  return __mpsin (fabs (x), 0, false);
 }
 
 /**************************************************************************/
@@ -672,16 +674,16 @@ slow2 (double x)
   double t = hp0 - fabs (x);
   res = do_cos_slow (t, hp1, 0, &cor);
   if (res == res + cor)
-    return (x > 0) ? res : -res;
+    return res;
 
   y = fabs (x) - hp0;
   y1 = y - hp1;
   y2 = (y - y1) - hp1;
   __docos (y1, y2, w);
   if (w[0] == w[0] + 1.000000005 * w[1])
-    return (x > 0) ? w[0] : -w[0];
+    return w[0];
 
-  return (x > 0) ? __mpsin (x, 0, false) : -__mpsin (-x, 0, false);
+  return __mpsin (fabs (x), 0, false);
 }
 
 /***************************************************************************/
-- 
2.7.4

  parent reply	other threads:[~2016-09-27 17:49 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-09-27 17:49 [PATCH 0/4] Use __copysign in sincos wherever possible Siddhesh Poyarekar
2016-09-27 17:49 ` [PATCH 2/4] Check n instead of k1 to decide on sign of sin/cos result Siddhesh Poyarekar
2016-09-28 19:55   ` Carlos O'Donell
2016-09-28 21:58     ` Siddhesh Poyarekar
2016-09-30  0:37       ` Carlos O'Donell
2016-10-05 19:08         ` Siddhesh Poyarekar
2016-09-27 17:49 ` [PATCH 3/4] Use copysign instead of ternary conditions for positive constants Siddhesh Poyarekar
2016-09-28 19:58   ` Carlos O'Donell
2016-09-27 17:49 ` [PATCH 4/4] Use copysign instead of ternary for some sin/cos input ranges Siddhesh Poyarekar
2016-09-28 12:59   ` Manfred
2016-09-28 20:04     ` Carlos O'Donell
2016-09-28 21:32     ` Siddhesh Poyarekar
2016-09-28 20:09   ` Carlos O'Donell
2016-09-27 17:49 ` Siddhesh Poyarekar [this message]
2016-09-27 20:03   ` [PATCH 1/4] consolidate sign checks for slow2 Carlos O'Donell
2016-09-27 19:10 ` [PATCH 0/4] Use __copysign in sincos wherever possible Carlos O'Donell
2016-09-27 19:18   ` Siddhesh Poyarekar

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