| commit | 380bd0fd2418f8988217de950f8b8ff18af0cb2b | |
| author | Joseph Myers <joseph@codesourcery.com> | |
| Thu, 26 Feb 2015 15:13:22 +0000 (26 15:13 +0000) | ||
| committer | Joseph Myers <joseph@codesourcery.com> | |
| Thu, 26 Feb 2015 15:14:58 +0000 (26 15:14 +0000) | ||
| tree | abb55a322fc5e1b829761d91a23510ecfc6bf1ee | treesnapshot (tar.gz zip) |
| parent | 4a28f4d55a6cc33474c0792fe93b5942d81bf185 | commitdiff |
Fix ldbl-128ibm logbl near powers of 2 (bug 18030).
The ldbl-128ibm implementation of logbl produces incorrect results
when the high part of the argument is a power of 2 and the low part a
nonzero number with the opposite sign (and so the returned exponent
should be 1 less than that of the high part). For example, logbl
(0x1.ffffffffffffffp1L) returns 2 but should return 1. (This is
similar to (fixed) bug 16740 for frexpl, and (fixed) bug 18029 for
ilogbl.) This patch adds checks for that case.
Tested for powerpc.
[BZ #18030]
* sysdeps/ieee754/ldbl-128ibm/s_logbl.c (__logbl): Adjust exponent
of power of 2 down when low part has opposite sign.
* math/libm-test.inc (logb_test_data): Add more tests.
The ldbl-128ibm implementation of logbl produces incorrect results
when the high part of the argument is a power of 2 and the low part a
nonzero number with the opposite sign (and so the returned exponent
should be 1 less than that of the high part). For example, logbl
(0x1.ffffffffffffffp1L) returns 2 but should return 1. (This is
similar to (fixed) bug 16740 for frexpl, and (fixed) bug 18029 for
ilogbl.) This patch adds checks for that case.
Tested for powerpc.
[BZ #18030]
* sysdeps/ieee754/ldbl-128ibm/s_logbl.c (__logbl): Adjust exponent
of power of 2 down when low part has opposite sign.
* math/libm-test.inc (logb_test_data): Add more tests.
| ChangeLog | diffblobblamehistory | |
| NEWS | diffblobblamehistory | |
| math/libm-test.inc | diffblobblamehistory | |
| sysdeps/ieee754/ldbl-128ibm/s_logbl.c | diffblobblamehistory |