[PATCH 2/7] sin/cos slow paths: remove large range reduction

This patch removes the large range reduction code and defers to the huge range
reduction code.  The first level range reducer supports inputs up to 2^27,
which is way too large given that inputs for sin/cos are typically small
(< 10), and optimizing for a smaller range would give a significant speedup.

Input values above 2^27 are practically never used, so there is no reason for
supporting range reduction between 2^27 and 2^48.  Removing it significantly
simplifies code and enables further speedups.  There is about a 2.3x slowdown
in this range due to __branred being extremely slow  (a better algorithm could
easily more than double performance).

	* sysdeps/ieee754/dbl-64/s_sin.c (reduce_sincos_2): Remove function.
	(do_sincos_2): Likewise.
	(__sin): Remove middle range reduction case.
	(__cos): Likewise.
	* sysdeps/ieee754/dbl-64/s_sincos.c (__sincos): Remove middle range
	reduction case.

1 files changed, 0 insertions, 10 deletions

diff --git a/sysdeps/ieee754/dbl-64/s_sincos.c b/sysdeps/ieee754/dbl-64/s_sincos.c
index e1977ea7e9..a9af8ce526 100644
--- a/sysdeps/ieee754/dbl-64/s_sincos.c
+++ b/sysdeps/ieee754/dbl-64/s_sincos.c
@@ -86,16 +86,6 @@ __sincos (double x, double *sinx, double *cosx)
 
       return;
     }
-  if (k < 0x42F00000)
-    {
-      double a, da;
-      int4 n = reduce_sincos_2 (x, &a, &da);
-
-      *sinx = do_sincos_2 (a, da, x, n, false);
-      *cosx = do_sincos_2 (a, da, x, n, true);
-
-      return;
-    }
   if (k < 0x7ff00000)
     {
       reduce_and_compute_sincos (x, sinx, cosx);