Fix rintf rounding.

diff --git a/ChangeLog b/ChangeLog
index e1f95328e7e2492a6bb7c6ee9d42f158486f84d1..f58688e881462366a373f8c50c500d70055e36e2 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2012-02-22  Joseph Myers  <joseph@codesourcery.com>
+
+       [BZ #2548]
+       * sysdeps/ieee754/flt-32/s_rintf.c (__rintf): Do not manipulate
+       bits before adding and subtracting TWO23[sx].
+       * math/libm-test.inc (rint_test): Add more tests.
+       (rint_test_tonearest): Likewise.
+       (rint_test_towardzero): Likewise.
+       (rint_test_downward): Likewise.
+       (rint_test_upward: Likewise.
+
 2012-02-22  Joseph Myers  <joseph@codesourcery.com>
 
        [BZ #10110]

diff --git a/NEWS b/NEWS
index b210474c3e2f3b1f368fde2660bd0d4a4e240c8e..31784546e2d1cbb06d7968993d192c7d265b177c 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -9,8 +9,8 @@ Version 2.16
 
 * The following bugs are resolved with this release:
 
-  174, 350, 411, 3335, 4026, 4596, 4822, 5077, 5805, 5993, 6884, 6907, 9739,
-  9902, 10110, 10140, 10210, 11174, 11322, 11494, 12047, 13058, 13525,
+  174, 350, 411, 2548, 3335, 4026, 4596, 4822, 5077, 5805, 5993, 6884, 6907,
+  9739, 9902, 10110, 10140, 10210, 11174, 11322, 11494, 12047, 13058, 13525,
   13526, 13527, 13528, 13529, 13530, 13531, 13532, 13533, 13547, 13551,
   13552, 13553, 13555, 13559, 13583, 13618, 13695, 13704
 

diff --git a/math/libm-test.inc b/math/libm-test.inc
index 6243e1ea3d630f429dac96517c122dfd0700bce2..c8186c814754802d0ae161e577a3634457c42285 100644 (file)
--- a/math/libm-test.inc
+++ b/math/libm-test.inc
@@ -5037,6 +5037,22 @@ rint_test (void)
   TEST_f_f (rint, 262142.75, 262143.0);
   TEST_f_f (rint, 524286.75, 524287.0);
   TEST_f_f (rint, 524288.75, 524289.0);
+  TEST_f_f (rint, 1048576.75, 1048577.0);
+  TEST_f_f (rint, 2097152.75, 2097153.0);
+  TEST_f_f (rint, -1048576.75, -1048577.0);
+  TEST_f_f (rint, -2097152.75, -2097153.0);
+#ifndef TEST_FLOAT
+  TEST_f_f (rint, 70368744177664.75, 70368744177665.0);
+  TEST_f_f (rint, 140737488355328.75, 140737488355329.0);
+  TEST_f_f (rint, 281474976710656.75, 281474976710657.0);
+  TEST_f_f (rint, 562949953421312.75, 562949953421313.0);
+  TEST_f_f (rint, 1125899906842624.75, 1125899906842625.0);
+  TEST_f_f (rint, -70368744177664.75, -70368744177665.0);
+  TEST_f_f (rint, -140737488355328.75, -140737488355329.0);
+  TEST_f_f (rint, -281474976710656.75, -281474976710657.0);
+  TEST_f_f (rint, -562949953421312.75, -562949953421313.0);
+  TEST_f_f (rint, -1125899906842624.75, -1125899906842625.0);
+#endif
 #ifdef TEST_LDOUBLE
   /* The result can only be represented in long double.  */
   TEST_f_f (rint, 4503599627370495.5L, 4503599627370496.0L);
@@ -5137,6 +5153,22 @@ rint_test_tonearest (void)
       TEST_f_f (rint, -0.1, -0.0);
       TEST_f_f (rint, -0.25, -0.0);
       TEST_f_f (rint, -0.625, -1.0);
+      TEST_f_f (rint, 1048576.75, 1048577.0);
+      TEST_f_f (rint, 2097152.75, 2097153.0);
+      TEST_f_f (rint, -1048576.75, -1048577.0);
+      TEST_f_f (rint, -2097152.75, -2097153.0);
+#ifndef TEST_FLOAT
+      TEST_f_f (rint, 70368744177664.75, 70368744177665.0);
+      TEST_f_f (rint, 140737488355328.75, 140737488355329.0);
+      TEST_f_f (rint, 281474976710656.75, 281474976710657.0);
+      TEST_f_f (rint, 562949953421312.75, 562949953421313.0);
+      TEST_f_f (rint, 1125899906842624.75, 1125899906842625.0);
+      TEST_f_f (rint, -70368744177664.75, -70368744177665.0);
+      TEST_f_f (rint, -140737488355328.75, -140737488355329.0);
+      TEST_f_f (rint, -281474976710656.75, -281474976710657.0);
+      TEST_f_f (rint, -562949953421312.75, -562949953421313.0);
+      TEST_f_f (rint, -1125899906842624.75, -1125899906842625.0);
+#endif
 #ifdef TEST_LDOUBLE
       /* The result can only be represented in long double.  */
       TEST_f_f (rint, 4503599627370495.5L, 4503599627370496.0L);
@@ -5207,6 +5239,22 @@ rint_test_towardzero (void)
       TEST_f_f (rint, -0.1, -0.0);
       TEST_f_f (rint, -0.25, -0.0);
       TEST_f_f (rint, -0.625, -0.0);
+      TEST_f_f (rint, 1048576.75, 1048576.0);
+      TEST_f_f (rint, 2097152.75, 2097152.0);
+      TEST_f_f (rint, -1048576.75, -1048576.0);
+      TEST_f_f (rint, -2097152.75, -2097152.0);
+#ifndef TEST_FLOAT
+      TEST_f_f (rint, 70368744177664.75, 70368744177664.0);
+      TEST_f_f (rint, 140737488355328.75, 140737488355328.0);
+      TEST_f_f (rint, 281474976710656.75, 281474976710656.0);
+      TEST_f_f (rint, 562949953421312.75, 562949953421312.0);
+      TEST_f_f (rint, 1125899906842624.75, 1125899906842624.0);
+      TEST_f_f (rint, -70368744177664.75, -70368744177664.0);
+      TEST_f_f (rint, -140737488355328.75, -140737488355328.0);
+      TEST_f_f (rint, -281474976710656.75, -281474976710656.0);
+      TEST_f_f (rint, -562949953421312.75, -562949953421312.0);
+      TEST_f_f (rint, -1125899906842624.75, -1125899906842624.0);
+#endif
 #ifdef TEST_LDOUBLE
       /* The result can only be represented in long double.  */
       TEST_f_f (rint, 4503599627370495.5L, 4503599627370495.0L);
@@ -5277,6 +5325,22 @@ rint_test_downward (void)
       TEST_f_f (rint, -0.1, -1.0);
       TEST_f_f (rint, -0.25, -1.0);
       TEST_f_f (rint, -0.625, -1.0);
+      TEST_f_f (rint, 1048576.75, 1048576.0);
+      TEST_f_f (rint, 2097152.75, 2097152.0);
+      TEST_f_f (rint, -1048576.75, -1048577.0);
+      TEST_f_f (rint, -2097152.75, -2097153.0);
+#ifndef TEST_FLOAT
+      TEST_f_f (rint, 70368744177664.75, 70368744177664.0);
+      TEST_f_f (rint, 140737488355328.75, 140737488355328.0);
+      TEST_f_f (rint, 281474976710656.75, 281474976710656.0);
+      TEST_f_f (rint, 562949953421312.75, 562949953421312.0);
+      TEST_f_f (rint, 1125899906842624.75, 1125899906842624.0);
+      TEST_f_f (rint, -70368744177664.75, -70368744177665.0);
+      TEST_f_f (rint, -140737488355328.75, -140737488355329.0);
+      TEST_f_f (rint, -281474976710656.75, -281474976710657.0);
+      TEST_f_f (rint, -562949953421312.75, -562949953421313.0);
+      TEST_f_f (rint, -1125899906842624.75, -1125899906842625.0);
+#endif
 #ifdef TEST_LDOUBLE
       /* The result can only be represented in long double.  */
       TEST_f_f (rint, 4503599627370495.5L, 4503599627370495.0L);
@@ -5347,6 +5411,22 @@ rint_test_upward (void)
       TEST_f_f (rint, -0.1, -0.0);
       TEST_f_f (rint, -0.25, -0.0);
       TEST_f_f (rint, -0.625, -0.0);
+      TEST_f_f (rint, 1048576.75, 1048577.0);
+      TEST_f_f (rint, 2097152.75, 2097153.0);
+      TEST_f_f (rint, -1048576.75, -1048576.0);
+      TEST_f_f (rint, -2097152.75, -2097152.0);
+#ifndef TEST_FLOAT
+      TEST_f_f (rint, 70368744177664.75, 70368744177665.0);
+      TEST_f_f (rint, 140737488355328.75, 140737488355329.0);
+      TEST_f_f (rint, 281474976710656.75, 281474976710657.0);
+      TEST_f_f (rint, 562949953421312.75, 562949953421313.0);
+      TEST_f_f (rint, 1125899906842624.75, 1125899906842625.0);
+      TEST_f_f (rint, -70368744177664.75, -70368744177664.0);
+      TEST_f_f (rint, -140737488355328.75, -140737488355328.0);
+      TEST_f_f (rint, -281474976710656.75, -281474976710656.0);
+      TEST_f_f (rint, -562949953421312.75, -562949953421312.0);
+      TEST_f_f (rint, -1125899906842624.75, -1125899906842624.0);
+#endif
 #ifdef TEST_LDOUBLE
       /* The result can only be represented in long double.  */
       TEST_f_f (rint, 4503599627370495.5L, 4503599627370496.0L);

diff --git a/sysdeps/ieee754/flt-32/s_rintf.c b/sysdeps/ieee754/flt-32/s_rintf.c
index 9ea9b6fc4f9b7ab55898c95c1d87ec71e4ce4333..9ba6b57d94753aa8253367e21d146b7c61c9ba29 100644 (file)
--- a/sysdeps/ieee754/flt-32/s_rintf.c
+++ b/sysdeps/ieee754/flt-32/s_rintf.c
@@ -26,34 +26,22 @@ float
 __rintf(float x)
 {
        int32_t i0,j0,sx;
-       u_int32_t i,i1;
        float w,t;
        GET_FLOAT_WORD(i0,x);
        sx = (i0>>31)&1;
        j0 = ((i0>>23)&0xff)-0x7f;
        if(j0<23) {
            if(j0<0) {
-               if((i0&0x7fffffff)==0) return x;
-               i1 = (i0&0x07fffff);
-               i0 &= 0xfff00000;
-               i0 |= ((i1|-i1)>>9)&0x400000;
-               SET_FLOAT_WORD(x,i0);
                w = TWO23[sx]+x;
                t =  w-TWO23[sx];
                GET_FLOAT_WORD(i0,t);
                SET_FLOAT_WORD(t,(i0&0x7fffffff)|(sx<<31));
                return t;
-           } else {
-               i = (0x007fffff)>>j0;
-               if((i0&i)==0) return x; /* x is integral */
-               i>>=1;
-               if((i0&i)!=0) i0 = (i0&(~i))|((0x100000)>>j0);
            }
        } else {
            if(j0==0x80) return x+x;    /* inf or NaN */
            else return x;              /* x is integral */
        }
-       SET_FLOAT_WORD(x,i0);
        w = TWO23[sx]+x;
        return w-TWO23[sx];
 }