From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 9C1243858401; Tue, 21 Nov 2023 16:31:01 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 9C1243858401 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1700584261; bh=A8pfqdoikmXlj6WA9sKoQnfdyBIiHZCTCvB2TRVapyk=; h=From:To:Subject:Date:In-Reply-To:References:From; b=Nev6mvULKTisVrJJYP3mTUNm1aQkl47VX1Tsx9HhZ8FiZAyOdzb0YBCz9IHmGMSlj ZiLB+RA8vg2oIjJqeoRTkZ3vG+2O0A7Zkf8U/reICeyN6LRbw1+5H5ZLo5NbqDMqIy UJQ4qCkLRh/MOMHTpaur3sd0mkPiY/H2PoAwLaWU= From: "burnus at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/110639] [OpenMP][5.1] Predefined firstprivate for pointers - attachment missing Date: Tue, 21 Nov 2023 16:31:01 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: middle-end X-Bugzilla-Version: 14.0 X-Bugzilla-Keywords: openmp, wrong-code X-Bugzilla-Severity: normal X-Bugzilla-Who: burnus at gcc dot gnu.org X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 List-Id: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D110639 --- Comment #2 from Tobias Burnus --- > If 'a' is already present on the device (e.g. 'omp target enter data map(= a)'), it works. This applies to both the comment 0 example where only a section of 'a' is mapped start > 0 and for the comment 1 example where the whole of 'a' is mapped. It also works fine if 'p' points inside 'A'. * * * As spec ref: TR12 states in "14.8 target Construct" [379:8-10]: "[C/C++] If a list item in a map clause has a base pointer that is predetermined firstprivate (see Section 6.1.1) and on entry to the target region the list item is mapped, the firstprivate pointer is updated via corresponding base pointer initialization." OpenMP 5.1 has in the mentioned C/C++-only section "2.21.7.2 Pointer Initialization for Device Data Environments" that is too long to be quoted. [The TR12 wording 'on entry to the target region' makes it clear that effectively ordering needs to happen. The 5.1 wording is a bit unclear whet= her it can be mapped with that very target construct - or the storage needs to = be present before the target directive. - However, the examples in OpenMP issue #1796 implies that also 5.1 permit mapping the data and the pointer be on t= he same directive.] * * * The implicit handling of the 'p' in this example happens in gimplify.cc's gimplify_adjust_omp_clauses_1 for 'else if (code =3D=3D OMP_CLAUSE_MAP && (= flags & GOVD_MAP_0LEN_ARRAY) !=3D 0)'.=