From a8e2112ae3e57fae592d84af2936a61d6239a248 Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Thu, 25 Jun 2015 21:46:02 +0000 Subject: Use round-to-nearest internally in jn, test with ALL_RM_TEST (bug 18602). Some existing jn tests, if run in non-default rounding modes, produce errors above those accepted in glibc, which causes problems for moving tests of jn to use ALL_RM_TEST. This patch makes jn set rounding to-nearest internally, as was done for yn some time ago, then computes the appropriate underflowing value for results that underflowed to zero in to-nearest, and moves the tests to ALL_RM_TEST. It does nothing about the general inaccuracy of Bessel function implementations in glibc, though it should make jn more accurate on average in non-default rounding modes through reduced error accumulation. The recomputation of results that underflowed to zero should as a side-effect fix some cases of bug 16559, where jn just used an exact zero, but that is *not* the goal of this patch and other cases of that bug remain unfixed. (Most of the changes in the patch are reindentation to add new scopes for SET_RESTORE_ROUND*.) Tested for x86_64, x86, powerpc and mips64. [BZ #16559] [BZ #18602] * sysdeps/ieee754/dbl-64/e_jn.c (__ieee754_jn): Set round-to-nearest internally then recompute results that underflowed to zero in the original rounding mode. * sysdeps/ieee754/flt-32/e_jnf.c (__ieee754_jnf): Likewise. * sysdeps/ieee754/ldbl-128/e_jnl.c (__ieee754_jnl): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_jnl.c (__ieee754_jnl): Likewise. * sysdeps/ieee754/ldbl-96/e_jnl.c (__ieee754_jnl): Likewise * math/libm-test.inc (jn_test): Use ALL_RM_TEST. * sysdeps/i386/fpu/libm-test-ulps: Update. * sysdeps/x86_64/fpu/libm-test-ulps: Likewise. --- sysdeps/i386/fpu/libm-test-ulps | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) (limited to 'sysdeps/i386/fpu') diff --git a/sysdeps/i386/fpu/libm-test-ulps b/sysdeps/i386/fpu/libm-test-ulps index c9b565f4fc..5a2af000fc 100644 --- a/sysdeps/i386/fpu/libm-test-ulps +++ b/sysdeps/i386/fpu/libm-test-ulps @@ -1613,6 +1613,30 @@ ifloat: 3 ildouble: 4 ldouble: 4 +Function: "jn_downward": +double: 2 +float: 3 +idouble: 2 +ifloat: 3 +ildouble: 4 +ldouble: 4 + +Function: "jn_towardzero": +double: 2 +float: 3 +idouble: 2 +ifloat: 3 +ildouble: 5 +ldouble: 5 + +Function: "jn_upward": +double: 2 +float: 3 +idouble: 2 +ifloat: 3 +ildouble: 5 +ldouble: 5 + Function: "lgamma": double: 1 float: 1 -- cgit v1.2.3