From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id B43C03858414; Fri, 31 Dec 2021 07:33:58 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org B43C03858414 From: "segher at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug rtl-optimization/63281] powerpc64le creates 64 bit constants from scratch instead of loading them Date: Fri, 31 Dec 2021 07:33:58 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: rtl-optimization X-Bugzilla-Version: 5.0 X-Bugzilla-Keywords: missed-optimization X-Bugzilla-Severity: enhancement X-Bugzilla-Who: segher at gcc dot gnu.org X-Bugzilla-Status: NEW 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 X-BeenThere: gcc-bugs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-bugs mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 31 Dec 2021 07:33:58 -0000 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D63281 --- Comment #18 from Segher Boessenkool --- Yes, it is slow. Five sequential dependent integer instructions instead of one load instruction. Depending on how you benchmark this you possibly won= 't see the slowness, the values are stored to memory and that can happen very many cycles later even, this is totally out of the critical path, will not clog up any pipelines.=