Fix ldbl-128 cos range reduction near pi/2 (bug 15429).

diff --git a/ChangeLog b/ChangeLog
index b6eae59..3ed5f44 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,10 @@
 2013-05-09  Joseph Myers  <joseph@codesourcery.com>
 
+       [BZ #15429]
+       * sysdeps/ieee754/ldbl-128/e_rem_pio2l.c (c): Use 113 bits for
+       high part of pi/2.
+       (__ieee754_rem_pio2l): Update comments.
+
        * math/libm-test.inc (M_SQRT_2_2): Remove macro.
        (csqrt_test): Use M_SQRT1_2l instead of M_SQRT_2_2.
 

diff --git a/NEWS b/NEWS
index 1a02e19..70e7ecf 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -16,7 +16,7 @@ Version 2.18
   15062, 15078, 15084, 15085, 15086, 15160, 15214, 15221, 15232, 15234,
   15283, 15285, 15287, 15304, 15305, 15307, 15309, 15327, 15330, 15335,
   15336, 15337, 15342, 15346, 15361, 15366, 15380, 15394, 15405, 15406,
-  15409, 15416, 15418, 15419, 15423, 15426.
+  15409, 15416, 15418, 15419, 15423, 15426, 15429.
 
 * CVE-2013-0242 Buffer overrun in regexp matcher has been fixed (Bugzilla
   #15078).

diff --git a/sysdeps/ieee754/ldbl-128/e_rem_pio2l.c b/sysdeps/ieee754/ldbl-128/e_rem_pio2l.c
index 84846fd..ee856ac 100644 (file)
--- a/sysdeps/ieee754/ldbl-128/e_rem_pio2l.c
+++ b/sysdeps/ieee754/ldbl-128/e_rem_pio2l.c
@@ -184,13 +184,13 @@ static const int32_t two_over_pi[] = {
 };
 
 static const long double c[] = {
-/* 93 bits of pi/2 */
+/* 113 bits of pi/2 */
 #define PI_2_1 c[0]
- 1.57079632679489661923132169155131424e+00L, /* 3fff921fb54442d18469898cc5100000 */
+ 0x1.921fb54442d18469898cc51701b8p+0L,
 
 /* pi/2 - PI_2_1 */
 #define PI_2_1t c[1]
- 8.84372056613570112025531863263659260e-29L, /* 3fa1c06e0e68948127044533e63a0106 */
+ 0x3.9a252049c1114cf98e804177d4c8p-116L,
 };
 
 int32_t __ieee754_rem_pio2l(long double x, long double *y)
@@ -213,7 +213,7 @@ int32_t __ieee754_rem_pio2l(long double x, long double *y)
     {
       if (hx > 0)
        { 
-         /* 113 + 93 bit PI is ok */
+         /* 113 + 113 bit PI is ok */
          z = x - PI_2_1;
          y[0] = z - PI_2_1t;
          y[1] = (z - y[0]) - PI_2_1t;
@@ -221,7 +221,7 @@ int32_t __ieee754_rem_pio2l(long double x, long double *y)
        }
       else
         {
-         /* 113 + 93 bit PI is ok */
+         /* 113 + 113 bit PI is ok */
          z = x + PI_2_1;
          y[0] = z + PI_2_1t;
          y[1] = (z - y[0]) + PI_2_1t;