From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 85A423858D38; Mon, 23 Jan 2023 15:54:26 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 85A423858D38 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1674489266; bh=bVJHIKKdJJkgd6YNjbS388EOKP0f1HPBuAnibfiQBMk=; h=From:To:Subject:Date:In-Reply-To:References:From; b=GGiLroFRoi6tEKMZPQwRYgJb+pYyR27fFOkXO3b5wUAkY2bLWVFhBQXJ7Xf3yRnOR AwB/u4m+5AFf0kvd5pc21Ts0B0NnFfeI95aQ3kc2SpXvEVc9C2Mb3dGEKF57d/nMY3 3Z9jnYOEqlTlqB7Of9oZRiFTCwmPwRNcIZdk2658= From: "kungfujesus06 at gmail dot com" To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/108498] ppc64 big endian generates uninitialized reads with -fstore-merging Date: Mon, 23 Jan 2023 15:54:26 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: middle-end X-Bugzilla-Version: 12.0 X-Bugzilla-Keywords: wrong-code X-Bugzilla-Severity: normal X-Bugzilla-Who: kungfujesus06 at gmail 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: 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 List-Id: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D108498 --- Comment #8 from Adam Stylinski --- Here's the code GCC emits: 00000000100007a0 <.emit_test>: 100007a0: 7c 08 02 a6 mflr r0 100007a4: fb e1 ff f8 std r31,-8(r1) 100007a8: 3d 42 ff fe addis r10,r2,-2 100007ac: 81 4a 8a 08 lwz r10,-30200(r10) 100007b0: 38 80 00 00 li r4,0 100007b4: 39 20 00 00 li r9,0 100007b8: 39 60 00 01 li r11,1 100007bc: 38 c0 00 02 li r6,2 100007c0: 38 e0 00 04 li r7,4 100007c4: 79 4a c1 e4 sldi r10,r10,24 100007c8: 39 00 00 08 li r8,8 100007cc: 38 a0 00 44 li r5,68 100007d0: f8 01 00 10 std r0,16(r1) 100007d4: f8 21 ff 31 stdu r1,-208(r1) 100007d8: 3c 00 02 00 lis r0,512 100007dc: 60 00 ff 03 ori r0,r0,65283 100007e0: 78 00 07 c6 sldi r0,r0,32 100007e4: 64 00 00 01 oris r0,r0,1 100007e8: 60 00 02 03 ori r0,r0,515 100007ec: eb ed 8f f0 ld r31,-28688(r13) 100007f0: fb e1 00 b8 std r31,184(r1) 100007f4: 3b e0 00 00 li r31,0 100007f8: f8 81 00 a8 std r4,168(r1) 100007fc: 38 81 00 74 addi r4,r1,116 10000800: f9 41 00 b0 std r10,176(r1) 10000804: 99 21 00 80 stb r9,128(r1) 10000808: 99 21 00 88 stb r9,136(r1) 1000080c: 7c 7f 1b 78 mr r31,r3 10000810: 99 21 00 a8 stb r9,168(r1) 10000814: 91 21 00 ac stw r9,172(r1) 10000818: f8 01 00 74 std r0,116(r1) 1000081c: 91 61 00 84 stw r11,132(r1) 10000820: 90 c1 00 8c stw r6,140(r1) 10000824: 98 e1 00 98 stb r7,152(r1) 10000828: 91 01 00 9c stw r8,156(r1) 1000082c: 4b ff fd 15 bl 10000540 <0000003b.plt_call.memcpy@@GLIBC_2.3> 10000830: e8 41 00 28 ld r2,40(r1) 10000834: e9 41 00 b8 ld r10,184(r1) 10000838: e9 2d 8f f0 ld r9,-28688(r13) 1000083c: 7d 4a 4a 79 xor. r10,r10,r9 10000840: 39 20 00 00 li r9,0 10000844: 40 82 00 1c bne 10000860 <.emit_test+0xc0> 10000848: 38 21 00 d0 addi r1,r1,208 1000084c: 7f e3 fb 78 mr r3,r31 10000850: e8 01 00 10 ld r0,16(r1) 10000854: eb e1 ff f8 ld r31,-8(r1) 10000858: 7c 08 03 a6 mtlr r0 1000085c: 4e 80 00 20 blr 10000860: 4b ff fd 41 bl 100005a0 <0000003b.plt_call.__stack_chk_fail@@GLIBC_2.4> 10000864: e8 41 00 28 ld r2,40(r1) 10000868: 00 00 00 00 .long 0x0 1000086c: 00 00 00 01 .long 0x1 10000870: 80 01 00 00 lwz r0,0(r1) 10000874: 60 00 00 00 nop 10000878: 00 00 00 00 .long 0x0 1000087c: 00 01 f7 78 .long 0x1f778=