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* Fix ldbl-96 scalblnl underflowing results (bug 17803).Joseph Myers2015-01-121-4/+4
| | | | | | | | | | | | | | | | | | | | | | | The ldbl-96 implementation of scalblnl (used for x86_64 and ia64) uses a condition k <= -63 to determine when a standard underflowing result tiny*__copysignl(tiny,x) should be returned. However, that condition corresponds to values with exponent -16446 or less, and in the case of -16446, the correct result for round-to-nearest depends on whether the value is exactly 0x1p-16446 (half the least subnormal) or more than that. This patch fixes the bug by changing the condition to k <= -64 and accordingly adjusting the exponent by 64 not 63 when converting to a normal value. Tested for x86_64. [BZ #17803] * sysdeps/ieee754/ldbl-96/s_scalblnl.c (twom63): Rename to twom64. Adjust value to 0x1p-64L. (__scalblnl): Only return standard underflowing result for K <= -64 not K <= -63; adjust exponent for underflowing result by 64 not 63. * math/libm-test.inc (scalbn_test_data): Add more tests. (scalbln_test_data): Likewise.
* Fix ldbl-96 scalblnl for subnormal arguments (bug 17834).Joseph Myers2015-01-121-2/+2
| | | | | | | | | | | | | | | | | | | | | | | The ldbl-96 implementation of scalblnl (used for x86_64 and ia64) is incorrect for subnormal arguments (this is a separate bug from bug 17803, which is about underflowing results). There are two problems with the adjustments of subnormal arguments: the "two63" variable multiplied by is actually 0x1p52L not 0x1p63L, so is insufficient to make values normal, and then GET_LDOUBLE_EXP(es,x), used to extract the new exponent, extracts it into a variable that isn't used, while the value taken to by the new exponent is wrongly taken from the high part of the mantissa before the adjustment (hx). This patch fixes both those problems and adds appropriate tests. Tested for x86_64. [BZ #17834] * sysdeps/ieee754/ldbl-96/s_scalblnl.c (two63): Change value to 0x1p63L. (__scalblnl): Get new exponent of adjusted subnormal value from ES not HX. * math/libm-test.inc (scalbn_test_data): Add more tests. (scalbln_test_data): Likewise.
* [BZ #6803] Set errno for scalbln, scalbnStefan Liebler2014-06-201-1/+0
| | | | | | | | | | | Errno is not set and the testcases will fail. Now the scalbln-aliases are removed in i386/m68 and the wrappers are used when calling the scalbln-functions. On ia64 only scalblnf has its own implementation. For scalbln and scalblnl the ieee754/dbl-64 and ieee754/ldbl-96 are used, thus the wrappers are needed, too.
* Use <> for math.h and math_private.h everywhere.Richard Henderson2012-03-091-2/+2
| | | | Entire tree edited via find | grep | sed.
* Fix scalbn, scalbln integer overflow.Joseph Myers2012-03-021-3/+5
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* Optimize scalblnUlrich Drepper2012-01-111-25/+13
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* Update.Ulrich Drepper1999-07-141-0/+71