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author | Joseph Myers <joseph@codesourcery.com> | 2015-06-21 18:43:10 +0000 |
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committer | Joseph Myers <joseph@codesourcery.com> | 2015-06-21 18:43:10 +0000 |
commit | cb0937b299182e78307795081489ec1f148bdbd7 (patch) | |
tree | 32137f8b8dde65185697602763252a45e40e8472 /sysdeps/i386/configure.ac | |
parent | fea1d8d67363c8b675a4c2533769ae12dc86efff (diff) | |
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Fix x86_64 / x86 expm1l (-min_subnorm) result sign (bug 18569).
In the x86 / x86_64 implementations of expm1l, when expm1l's result
should underflow to 0 (argument minus the least subnormal, in some
rounding modes), it can be a zero of the wrong sign. This patch fixes
this by returning the argument with underflow forced in that case
(this is a 1ulp error relative to the correctly rounded result of -0,
which is OK in terms of the documented accuracy goals, whereas a
result with the wrong sign never is).
Tested for x86_64 and x86.
[BZ #18569]
* sysdeps/i386/fpu/e_expl.S (IEEE754_EXPL) [USE_AS_EXPM1L]: Force
underflow and return argument in case of subnormal argument.
* sysdeps/x86_64/fpu/e_expl.S (IEEE754_EXPL) [USE_AS_EXPM1L]:
Likewise.
* math/auto-libm-test-in: Add more tests of expm1.
* math/auto-libm-test-out: Regenerated.
Diffstat (limited to 'sysdeps/i386/configure.ac')
0 files changed, 0 insertions, 0 deletions