Fix remainder exceptions and directed-rounding results (bugs 15480, 15485).

4 files changed, 181 insertions, 8 deletions

diff --git a/ChangeLog b/ChangeLog
index cec25f7..fe2a644 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,22 @@
 2013-05-17  Joseph Myers  <joseph@codesourcery.com>
 
+	[BZ #15480]
+	[BZ #15485]
+	* sysdeps/ieee754/dbl-64/e_remainder.c (__ieee754_remainder): For
+	main case of finite arguments, set rounding mode to FE_TONEAREST
+	and discard exceptions.
+	* math/libm-test.inc (remainder_test_data): Disallow "inexact"
+	exceptions.
+	(remainder_tonearest_test_data): New variable.
+	(remainder_test_tonearest): New function.
+	(remainder_towardzero_test_data): New variable.
+	(remainder_test_towardzero): New function.
+	(remainder_downward_test_data): New variable.
+	(remainder_test_downward): New function.
+	(remainder_upward_test_data): New variable.
+	(remainder_test_upward): New function.
+	(main): Call the new test functions.
+
 	* math/libm-test.inc (struct test_f_f1_data): Remove field
 	extra_init.
 	(struct test_fF_f1_data): Likewise.
diff --git a/NEWS b/NEWS
index 57c7ee0..7fc3e39 100644
--- a/NEWS
+++ b/NEWS
@@ -17,7 +17,7 @@ Version 2.18
   15086, 15160, 15214, 15221, 15232, 15234, 15283, 15285, 15287, 15304,
   15305, 15307, 15309, 15327, 15330, 15335, 15336, 15337, 15342, 15346,
   15359, 15361, 15366, 15380, 15394, 15395, 15405, 15406, 15409, 15416,
-  15418, 15419, 15423, 15424, 15426, 15429, 15442, 15448.
+  15418, 15419, 15423, 15424, 15426, 15429, 15442, 15448, 15480, 15485.
 
 * CVE-2013-0242 Buffer overrun in regexp matcher has been fixed (Bugzilla
   #15078).
diff --git a/math/libm-test.inc b/math/libm-test.inc
index 360112c..41344bc 100644
--- a/math/libm-test.inc
+++ b/math/libm-test.inc
@@ -12276,13 +12276,12 @@ static const struct test_ff_f_data remainder_test_data[] =
     TEST_ff_f (remainder, 7.0, plus_infty, 7.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_ff_f (remainder, 7.0, minus_infty, 7.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
 
-    /* Bug 15480: spurious "inexact" exception may occur.  */
-    TEST_ff_f (remainder, 1.625, 1.0, -0.375),
-    TEST_ff_f (remainder, -1.625, 1.0, 0.375),
-    TEST_ff_f (remainder, 1.625, -1.0, -0.375),
-    TEST_ff_f (remainder, -1.625, -1.0, 0.375),
-    TEST_ff_f (remainder, 5.0, 2.0, 1.0),
-    TEST_ff_f (remainder, 3.0, 2.0, -1.0),
+    TEST_ff_f (remainder, 1.625, 1.0, -0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, -1.625, 1.0, 0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, 1.625, -1.0, -0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, -1.625, -1.0, 0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, 5.0, 2.0, 1.0, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, 3.0, 2.0, -1.0, NO_INEXACT_EXCEPTION),
     END_DATA (remainder)
   };
 
@@ -12294,6 +12293,158 @@ remainder_test (void)
   END (remainder);
 }
 
+
+static const struct test_ff_f_data remainder_tonearest_test_data[] =
+  {
+    START_DATA (remainder_tonearest),
+    TEST_ff_f (remainder, 1, 0, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, 1, minus_zero, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, plus_infty, minus_zero, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, plus_infty, 0, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, plus_infty, 1, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, plus_infty, 2, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, minus_infty, minus_zero, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, minus_infty, 0, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, minus_infty, 1, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, minus_infty, 2, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, qnan_value, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (remainder, 0, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (remainder, qnan_value, 0, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+
+    TEST_ff_f (remainder, 7.0, plus_infty, 7.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (remainder, 7.0, minus_infty, 7.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+
+    TEST_ff_f (remainder, 1.625, 1.0, -0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, -1.625, 1.0, 0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, 1.625, -1.0, -0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, -1.625, -1.0, 0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, 5.0, 2.0, 1.0, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, 3.0, 2.0, -1.0, NO_INEXACT_EXCEPTION),
+    END_DATA (remainder_tonearest)
+  };
+
+static void
+remainder_test_tonearest (void)
+{
+  START (remainder_tonearest);
+  RUN_TEST_LOOP_ff_f (remainder, remainder_tonearest_test_data, FE_TONEAREST);
+  END (remainder_tonearest);
+}
+
+
+static const struct test_ff_f_data remainder_towardzero_test_data[] =
+  {
+    START_DATA (remainder_towardzero),
+    TEST_ff_f (remainder, 1, 0, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, 1, minus_zero, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, plus_infty, minus_zero, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, plus_infty, 0, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, plus_infty, 1, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, plus_infty, 2, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, minus_infty, minus_zero, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, minus_infty, 0, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, minus_infty, 1, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, minus_infty, 2, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, qnan_value, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (remainder, 0, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (remainder, qnan_value, 0, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+
+    TEST_ff_f (remainder, 7.0, plus_infty, 7.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (remainder, 7.0, minus_infty, 7.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+
+    TEST_ff_f (remainder, 1.625, 1.0, -0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, -1.625, 1.0, 0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, 1.625, -1.0, -0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, -1.625, -1.0, 0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, 5.0, 2.0, 1.0, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, 3.0, 2.0, -1.0, NO_INEXACT_EXCEPTION),
+    END_DATA (remainder_towardzero)
+  };
+
+static void
+remainder_test_towardzero (void)
+{
+  START (remainder_towardzero);
+  RUN_TEST_LOOP_ff_f (remainder, remainder_towardzero_test_data, FE_TOWARDZERO);
+  END (remainder_towardzero);
+}
+
+
+static const struct test_ff_f_data remainder_downward_test_data[] =
+  {
+    START_DATA (remainder_downward),
+    TEST_ff_f (remainder, 1, 0, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, 1, minus_zero, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, plus_infty, minus_zero, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, plus_infty, 0, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, plus_infty, 1, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, plus_infty, 2, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, minus_infty, minus_zero, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, minus_infty, 0, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, minus_infty, 1, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, minus_infty, 2, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, qnan_value, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (remainder, 0, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (remainder, qnan_value, 0, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+
+    TEST_ff_f (remainder, 7.0, plus_infty, 7.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (remainder, 7.0, minus_infty, 7.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+
+    TEST_ff_f (remainder, 1.625, 1.0, -0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, -1.625, 1.0, 0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, 1.625, -1.0, -0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, -1.625, -1.0, 0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, 5.0, 2.0, 1.0, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, 3.0, 2.0, -1.0, NO_INEXACT_EXCEPTION),
+    END_DATA (remainder_downward)
+  };
+
+static void
+remainder_test_downward (void)
+{
+  START (remainder_downward);
+  RUN_TEST_LOOP_ff_f (remainder, remainder_downward_test_data, FE_DOWNWARD);
+  END (remainder_downward);
+}
+
+
+static const struct test_ff_f_data remainder_upward_test_data[] =
+  {
+    START_DATA (remainder_upward),
+    TEST_ff_f (remainder, 1, 0, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, 1, minus_zero, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, plus_infty, minus_zero, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, plus_infty, 0, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, plus_infty, 1, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, plus_infty, 2, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, minus_infty, minus_zero, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, minus_infty, 0, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, minus_infty, 1, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, minus_infty, 2, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, qnan_value, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (remainder, 0, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (remainder, qnan_value, 0, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+
+    TEST_ff_f (remainder, 7.0, plus_infty, 7.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (remainder, 7.0, minus_infty, 7.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+
+    TEST_ff_f (remainder, 1.625, 1.0, -0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, -1.625, 1.0, 0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, 1.625, -1.0, -0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, -1.625, -1.0, 0.375, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, 5.0, 2.0, 1.0, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (remainder, 3.0, 2.0, -1.0, NO_INEXACT_EXCEPTION),
+    END_DATA (remainder_upward)
+  };
+
+static void
+remainder_test_upward (void)
+{
+  START (remainder_upward);
+  RUN_TEST_LOOP_ff_f (remainder, remainder_upward_test_data, FE_UPWARD);
+  END (remainder_upward);
+}
+
 static const struct test_ffI_f1_data remquo_test_data[] =
   {
     START_DATA (remquo),
@@ -14766,6 +14917,10 @@ main (int argc, char **argv)
   /* Remainder functions:  */
   fmod_test ();
   remainder_test ();
+  remainder_test_tonearest ();
+  remainder_test_towardzero ();
+  remainder_test_downward ();
+  remainder_test_upward ();
   remquo_test ();
 
   /* Manipulation functions:  */
diff --git a/sysdeps/ieee754/dbl-64/e_remainder.c b/sysdeps/ieee754/dbl-64/e_remainder.c
index 39ca0c2..2d20bb1 100644
--- a/sysdeps/ieee754/dbl-64/e_remainder.c
+++ b/sysdeps/ieee754/dbl-64/e_remainder.c
@@ -51,6 +51,7 @@ double __ieee754_remainder(double x, double y)
   ky=t.i[HIGH_HALF];
   /*------ |x| < 2^1023  and   2^-970 < |y| < 2^1024 ------------------*/
   if (kx<0x7fe00000 && ky<0x7ff00000 && ky>=0x03500000) {
+    SET_RESTORE_ROUND_NOEX (FE_TONEAREST);
     if (kx+0x00100000<ky) return x;
     if ((kx-0x01500000)<ky) {
       z=x/t.x;