From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 15020 invoked by alias); 23 Jul 2014 12:38:43 -0000 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 Received: (qmail 14971 invoked by uid 48); 23 Jul 2014 12:38:40 -0000 From: "rguenth at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug target/61872] Assigning to "long double" causes memset to be improperly elided Date: Wed, 23 Jul 2014 12:38:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: target X-Bugzilla-Version: 4.8.2 X-Bugzilla-Keywords: wrong-code X-Bugzilla-Severity: normal X-Bugzilla-Who: rguenth at gcc dot gnu.org X-Bugzilla-Status: NEW 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: 7bit X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-SW-Source: 2014-07/txt/msg01561.txt.bz2 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61872 --- Comment #3 from Richard Biener --- Old value = 12 '\f' New value = 16 '\020' init_adjust_machine_modes () at insn-modes.c:1069 1066 /* config/i386/i386-modes.def:34 */ 1067 s = TARGET_128BIT_LONG_DOUBLE ? 16 : 12; 1068 mode_size[XFmode] = s; 1069 mode_base_align[XFmode] = s & (~s + 1); /* In ILP32 mode, XFmode has size 12 and alignment 4. In LP64 mode, XFmode has size and alignment 16. */ ADJUST_FLOAT_FORMAT (XF, (TARGET_128BIT_LONG_DOUBLE ? &ieee_extended_intel_128_format : TARGET_96_ROUND_53_LONG_DOUBLE ? &ieee_extended_intel_96_round_53_format : &ieee_extended_intel_96_format)); ok, but with that you need to adjust the insns to actually store 16bits. Target bug.