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 4C53A385840C; Sat,  2 Mar 2024 01:15:19 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 4C53A385840C
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org;
	s=default; t=1709342119;
	bh=7PQFak5OKV8TWH7e7DNOnVlcSebz0SmIu4+g7N7oqiU=;
	h=From:To:Subject:Date:From;
	b=IS9KnOSw1aT0JteXeRI1dIJpxQM63uNM9qpjfokxi5V4okLlAzE4NSx0iZQ7oDxq6
	 5kNy5qmQX0r4O0S9/aEaJYzy/lCtIBdFc/7iav8RBRJSVzGqbqu94lGJiY7nJFhUtn
	 i6ylKdrtX55TYt+agi2im2ENli/TCEFnrfei4H1I=
From: "patrick at rivosinc dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/114200] New: [14] RISC-V fixed-length vector miscompile
 at -O3
Date: Sat, 02 Mar 2024 01:15:18 +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: 14.0
X-Bugzilla-Keywords: 
X-Bugzilla-Severity: normal
X-Bugzilla-Who: patrick at rivosinc dot com
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-114200-4@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=3D114200

            Bug ID: 114200
           Summary: [14] RISC-V fixed-length vector miscompile at -O3
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: patrick at rivosinc dot com
  Target Milestone: ---

Testcase:
int printf(const char *, ...);
short a, e =3D 1;
_Bool b, d;
short c[300];
int main() {
  for (int f =3D 0; f < 19; f++) {
    for (int g =3D 0; g < 14; g++)
      for (int h =3D 0; h < 10; h++)
        a +=3D c[g] + e;
    b +=3D d;
  }
  printf("%d\n", a);
}

Commands:
> /scratch/tc-testing/tc-feb-20/build-rv64gcv/bin/riscv64-unknown-linux-gnu=
-gcc -march=3Drv64gcv -O3 --param=3Driscv-autovec-preference=3Dfixed-vlmax =
red.c -o red.out
> /scratch/tc-testing/tc-feb-20-llvm/build/bin/qemu-riscv64 red.out
2318
> /scratch/tc-testing/tc-feb-20/build-rv64gcv/bin/riscv64-unknown-linux-gnu=
-gcc -march=3Drv64gcv -O2 --param=3Driscv-autovec-preference=3Dfixed-vlmax =
red.c -o red.out
> /scratch/tc-testing/tc-feb-20-llvm/build/bin/qemu-riscv64 red.out
2660

Tested/found using r14-9084-g61ab046a327 (not bisected)

Found using fuzzer=