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From: "g.peterhoff@t-online.de" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug libstdc++/77776] C++17 std::hypot implementation is poor Date: Tue, 19 Mar 2024 00:09:03 +0000 [thread overview] Message-ID: <bug-77776-4-qwf0tEgLUv@http.gcc.gnu.org/bugzilla/> (raw) In-Reply-To: <bug-77776-4@http.gcc.gnu.org/bugzilla/> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77776 --- Comment #23 from g.peterhoff@t-online.de --- Hello Matthias, you've given me new ideas. I think we agree on implementing hypot3 using a scaling factor. But the correct value is not yet implemented here either; do you have a suggestion? A version here: https://godbolt.org/z/Gd53cG9YG I've intentionally broken hypot_gp into small pieces so that you can play around with it. This is of course unnecessary for a final version. General * The function must of course work efficiently with all FP types. Questions * Sorting: It is theoretically sufficient to sort the values x,y,z only to the extent that the condition x,y <= z is fulfilled (HYPOT_SORT_FULL). * Accuracy: This is better with fma (HYPOT_FMA). * How do you create the benchmarks? I could do this myself without getting on your nerves. thx Gero
next prev parent reply other threads:[~2024-03-19 0:09 UTC|newest] Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top [not found] <bug-77776-4@http.gcc.gnu.org/bugzilla/> 2021-05-04 12:31 ` rguenth at gcc dot gnu.org 2024-02-29 18:23 ` g.peterhoff@t-online.de 2024-03-01 12:27 ` redi at gcc dot gnu.org 2024-03-02 15:52 ` g.peterhoff@t-online.de 2024-03-04 3:49 ` de34 at live dot cn 2024-03-04 10:45 ` mkretz at gcc dot gnu.org 2024-03-04 11:12 ` jakub at gcc dot gnu.org 2024-03-04 17:14 ` mkretz at gcc dot gnu.org 2024-03-04 20:21 ` jakub at gcc dot gnu.org 2024-03-06 2:47 ` g.peterhoff@t-online.de 2024-03-06 9:43 ` mkretz at gcc dot gnu.org 2024-03-06 12:35 ` redi at gcc dot gnu.org 2024-03-12 11:31 ` mkretz at gcc dot gnu.org 2024-03-19 0:09 ` g.peterhoff@t-online.de [this message] 2024-03-25 10:06 ` mkretz at gcc dot gnu.org 2024-04-05 1:08 ` g.peterhoff@t-online.de 2024-04-05 1:23 ` g.peterhoff@t-online.de 2024-04-10 16:41 ` g.peterhoff@t-online.de 2024-04-10 16:48 ` jakub at gcc dot gnu.org 2024-04-10 18:08 ` g.peterhoff@t-online.de
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