From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugzilla@gcc.gnu.org>
Received: by sourceware.org (Postfix, from userid 48)
	id 2DA50386546B; Wed, 22 May 2024 14:06:32 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 2DA50386546B
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org;
	s=default; t=1716386792;
	bh=VN/U3IY47xnnvNM157CwnXZub1HjKYpSGDuFJKcOIeo=;
	h=From:To:Subject:Date:From;
	b=DnSCIHFt2eTL4UOBBJ4K+vtw9Y9pxIEtjrbXopbD1/PaH+iosXoMpNMxrS1Qm3hLv
	 dqAaJWUq3LWUQcUMsnxmuH5jOn6aBTGRUCVwD7QEYboK2Nu94bj570hCyA3hq/u1B1
	 dig8tgeLae6ojihVOAtKZSJqVuG1EE9mxAuzZrmM=
From: "ebotcazou at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/115188] New: [14/15 regression] invalid Thumb assembly
 for atomic store in loop on ARMv6
Date: Wed, 22 May 2024 14:06:31 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: new
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: target
X-Bugzilla-Version: 14.1.0
X-Bugzilla-Keywords: 
X-Bugzilla-Severity: normal
X-Bugzilla-Who: ebotcazou 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: bug_id short_desc product version bug_status
 bug_severity priority component assigned_to reporter target_milestone
Message-ID: <bug-115188-4@http.gcc.gnu.org/bugzilla/>
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: <gcc-bugs.sourceware.org>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D115188

            Bug ID: 115188
           Summary: [14/15 regression] invalid Thumb assembly for atomic
                    store in loop on ARMv6
           Product: gcc
           Version: 14.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ebotcazou at gcc dot gnu.org
  Target Milestone: ---

This apparently comes from the fix for PR target/111235: the following code:

int data[4];

void init (unsigned int lb, unsigned int hb)
{
  for (unsigned int i =3D lb; i < hb; i++)
    __atomic_store_4 (&data[i], 0, __ATOMIC_RELAXED);
}

yields invalid assembly when compiled with -mthumb -mcpu=3Dcortex-m0 -O2:

t.s: Assembler messages:
t.s:35: Warning: missing operand; zero assumed
t.s:35: Error: cannot use register index with PC-relative addressing -- `str
r1,r0!'=