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From: "cvs-commit at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/95079] unorderd_map::insert_or_assign and try_emplace
 should only hash and mod once unless there is a rehash.
Date: Fri, 29 May 2020 11:13:16 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D95079

--- Comment #3 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Fran=C3=A0=C2=A4=C2=A5=C3=A0=C2=A4ois=
 Dumont
<fdumont@gcc.gnu.org>:

https://gcc.gnu.org/g:7688e5e8c4d46102a0cc0b9c25191ac7dde0d285

commit r11-719-g7688e5e8c4d46102a0cc0b9c25191ac7dde0d285
Author: Fran=C3=A7ois Dumont <fdumont@gcc.gnu.org>
Date:   Sun May 24 12:04:38 2020 +0200

    libstdc++: Review unordered_map insert_or_assign/try_emplace (PR 95079)

    Those methods are making a double lookup in case of insertion, they can
    perform only one.

            PR libstdc++/95079
            * include/bits/hashtable_policy.h (_Insert_base<>::try_emplace):
New.
            * include/bits/unordered_map.h (unordered_map<>::try_emplace):
Adapt.
            (unordered_map<>::insert_or_assign): Adapt.=