From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 21758 invoked by alias); 1 Dec 2012 20:26:51 -0000 Received: (qmail 21498 invoked by uid 48); 1 Dec 2012 20:26:33 -0000 From: "hjl.tools at gmail dot com" To: gcc-bugs@gcc.gnu.org Subject: [Bug target/50829] avx extra copy for _mm256_insertf128_pd Date: Sat, 01 Dec 2012 20:26:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: target X-Bugzilla-Keywords: ra X-Bugzilla-Severity: enhancement X-Bugzilla-Who: hjl.tools at gmail dot com X-Bugzilla-Status: NEW X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Changed-Fields: CC Message-ID: In-Reply-To: References: X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated Content-Type: text/plain; charset="UTF-8" MIME-Version: 1.0 Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org X-SW-Source: 2012-12/txt/msg00045.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50829 H.J. Lu changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |areg.melikadamyan at gmail | |dot com, hjl.tools at gmail | |dot com --- Comment #11 from H.J. Lu 2012-12-01 20:26:32 UTC --- (In reply to comment #10) > Created attachment 28846 [details] > Use subreg > > Hmm, I don't understand why we use UNSPEC_CAST. I tried the attached patch to > use a subreg instead. It passed bootstrap+testsuite and generates optimal code > for the testcase of this PR. > > So, any idea what advantage the unspec has over a subreg? And if none, what is > the best way to use a subreg? subreg didn't work before.