This is the mail archive of the libc-alpha@sourceware.org mailing list for the glibc project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Fix ldbl-96 remquol (finite, Inf) (bug 18244) [committed]


ldbl-96 remquol wrongly handles the case where the first argument is
finite and the second infinite, because the check for the second
argument being a NaN fails to disregard the explicit high mantissa bit
and so wrongly interprets an infinity as being a NaN.  This patch
fixes this by masking off that bit, and improves test coverage for
both remainder and remquo (various cases were missing tests, or, as in
the case of the bug, were tested only for one of the two functions).

Tested for x86_64 and x86.

2015-05-19  Joseph Myers  <joseph@codesourcery.com>

	[BZ #18244]
	* sysdeps/ieee754/ldbl-96/s_remquol.c (__remquol): Ignore explicit
	high mantissa bit when testing whether P is a NaN.
	* math/libm-test.inc (remainder_test_data): Add more tests.
	(remquo_test_data): Likewise.

diff --git a/math/libm-test.inc b/math/libm-test.inc
index a6cf771..85a1746 100644
--- a/math/libm-test.inc
+++ b/math/libm-test.inc
@@ -8719,17 +8719,31 @@ static const struct test_ff_f_data remainder_test_data[] =
   {
     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_zero, plus_zero, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, plus_zero, minus_zero, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, minus_zero, plus_zero, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, minus_zero, 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, plus_infty, plus_infty, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, plus_infty, minus_infty, 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, minus_infty, plus_infty, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_ff_f (remainder, minus_infty, minus_infty, 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, 1, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (remainder, qnan_value, 1, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (remainder, plus_infty, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (remainder, qnan_value, plus_infty, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (remainder, minus_infty, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (remainder, qnan_value, minus_infty, 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),
@@ -8763,9 +8777,32 @@ static const struct test_ffI_f1_data remquo_test_data[] =
   {
     TEST_ffI_f1 (remquo, 1, 0, qnan_value, IGNORE, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
     TEST_ffI_f1 (remquo, 1, minus_zero, qnan_value, IGNORE, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
+    TEST_ffI_f1 (remquo, plus_zero, plus_zero, qnan_value, IGNORE, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
+    TEST_ffI_f1 (remquo, plus_zero, minus_zero, qnan_value, IGNORE, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
+    TEST_ffI_f1 (remquo, minus_zero, plus_zero, qnan_value, IGNORE, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
+    TEST_ffI_f1 (remquo, minus_zero, minus_zero, qnan_value, IGNORE, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
+    TEST_ffI_f1 (remquo, plus_infty, minus_zero, qnan_value, IGNORE, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
+    TEST_ffI_f1 (remquo, plus_infty, 0, qnan_value, IGNORE, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
     TEST_ffI_f1 (remquo, plus_infty, 1, qnan_value, IGNORE, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
+    TEST_ffI_f1 (remquo, plus_infty, plus_infty, qnan_value, IGNORE, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
+    TEST_ffI_f1 (remquo, plus_infty, minus_infty, qnan_value, IGNORE, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
+    TEST_ffI_f1 (remquo, minus_infty, minus_zero, qnan_value, IGNORE, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
+    TEST_ffI_f1 (remquo, minus_infty, 0, qnan_value, IGNORE, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
     TEST_ffI_f1 (remquo, minus_infty, 1, qnan_value, IGNORE, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
+    TEST_ffI_f1 (remquo, minus_infty, plus_infty, qnan_value, IGNORE, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
+    TEST_ffI_f1 (remquo, minus_infty, minus_infty, qnan_value, IGNORE, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
     TEST_ffI_f1 (remquo, qnan_value, qnan_value, qnan_value, IGNORE, NO_INEXACT_EXCEPTION),
+    TEST_ffI_f1 (remquo, 0, qnan_value, qnan_value, IGNORE, NO_INEXACT_EXCEPTION),
+    TEST_ffI_f1 (remquo, qnan_value, 0, qnan_value, IGNORE, NO_INEXACT_EXCEPTION),
+    TEST_ffI_f1 (remquo, 1, qnan_value, qnan_value, IGNORE, NO_INEXACT_EXCEPTION),
+    TEST_ffI_f1 (remquo, qnan_value, 1, qnan_value, IGNORE, NO_INEXACT_EXCEPTION),
+    TEST_ffI_f1 (remquo, plus_infty, qnan_value, qnan_value, IGNORE, NO_INEXACT_EXCEPTION),
+    TEST_ffI_f1 (remquo, qnan_value, plus_infty, qnan_value, IGNORE, NO_INEXACT_EXCEPTION),
+    TEST_ffI_f1 (remquo, minus_infty, qnan_value, qnan_value, IGNORE, NO_INEXACT_EXCEPTION),
+    TEST_ffI_f1 (remquo, qnan_value, minus_infty, qnan_value, IGNORE, NO_INEXACT_EXCEPTION),
+
+    TEST_ffI_f1 (remquo, 7.0, plus_infty, 7.0, 0, NO_INEXACT_EXCEPTION),
+    TEST_ffI_f1 (remquo, 7.0, minus_infty, 7.0, 0, NO_INEXACT_EXCEPTION),
 
     TEST_ffI_f1 (remquo, 1.625, 1.0, -0.375, 2, NO_INEXACT_EXCEPTION),
     TEST_ffI_f1 (remquo, -1.625, 1.0, 0.375, -2, NO_INEXACT_EXCEPTION),
diff --git a/sysdeps/ieee754/ldbl-96/s_remquol.c b/sysdeps/ieee754/ldbl-96/s_remquol.c
index 8d6b10e..230d0fa 100644
--- a/sysdeps/ieee754/ldbl-96/s_remquol.c
+++ b/sysdeps/ieee754/ldbl-96/s_remquol.c
@@ -44,7 +44,7 @@ __remquol (long double x, long double p, int *quo)
     return (x * p) / (x * p); 			/* p = 0 */
   if ((ex == 0x7fff)				/* x not finite */
       || ((ep == 0x7fff)			/* p is NaN */
-	  && ((hp | lp) != 0)))
+	  && (((hp & 0x7fffffff) | lp) != 0)))
     return (x * p) / (x * p);
 
   if (ep <= 0x7ffb)

-- 
Joseph S. Myers
joseph@codesourcery.com


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]