From 43576de04afc6a0896a3ecc094e1581069a0652a Mon Sep 17 00:00:00 2001 From: Paul Zimmermann Date: Fri, 2 Apr 2021 08:21:06 +0200 Subject: Improve the accuracy of tgamma (BZ #26983) With this patch, the maximal known error for tgamma is now reduced to 9 ulps for dbl-64, for all rounding modes. Since exhaustive testing is not possible for dbl-64, it might be that there are still cases with an error larger than 9 ulps, but all known cases are fixed (intensive tests were done to find cases with large errors). Tested on x86_64 and powerpc (and by Adhemerval Zanella on aarch64, arm, s390x, sparc, and i686). Reviewed-by: Adhemerval Zanella --- math/auto-libm-test-in | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'math/auto-libm-test-in') diff --git a/math/auto-libm-test-in b/math/auto-libm-test-in index 9fbd0c626b..2045a0f8d1 100644 --- a/math/auto-libm-test-in +++ b/math/auto-libm-test-in @@ -8251,8 +8251,12 @@ tgamma -0x6.ce9158p+0 tgamma -0xd.cbf53d0e7d06p+0 # the next value generates larger error bounds on x86_64 (binary32) tgamma -0x3.0aa534p+0 -# the next value generates larger error bounds on x86_64 (binary64) +# the next values generate large error bounds on x86_64 (binary64) tgamma -0x1.62b8c36c7180bp+4 +tgamma -0x1.62c4d519e8677p+3 +tgamma -0x1.c033cc426752fp+2 +tgamma -0x1.62cfd0d34ade2p+3 +tgamma -0x1.8814da6eb7dbp+5 y0 0.125 y0 0.75 -- cgit v1.2.3