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From: "rearnsha at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/54300] [4.7 Regression] Erroneous optimization causes wrong Neon data management
Date: Fri, 04 Oct 2013 17:29:00 -0000 [thread overview]
Message-ID: <bug-54300-4-Ond455REsc@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-54300-4@http.gcc.gnu.org/bugzilla/>
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54300
Richard Earnshaw <rearnsha at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Component|target |rtl-optimization
Known to fail| |4.9.0
--- Comment #9 from Richard Earnshaw <rearnsha at gcc dot gnu.org> ---
This is regcprop messing up. After the ce3 pass we have:
(insn 18 30 73 4 (set (reg:V4HI 54 d19 [orig:113 D.16370 ] [113])
(unspec:V4HI [
(mem:V4HI (reg:SI 14 lr [128]) [0 MEM[(const
__builtin_neon_hi[4] *)_21]+0 S8 A16])
] UNSPEC_VLD1))
/work/rearnsha/scratch/gnu/gcc/trunk/gcc/include/arm_neon.h:8019 1662
{neon_vld1v4hi}
(nil))
(insn 73 18 27 4 (parallel [
(set (reg:V4HI 52 d18 [ D.16372 ])
(reg:V4HI 54 d19 [orig:113 D.16370 ] [113]))
(set (reg:V4HI 54 d19 [ D.16372+8 ])
(reg:V4HI 52 d18 [orig:120 D.16370 ] [120]))
]) /work/rearnsha/scratch/gnu/gcc/trunk/gcc/include/arm_neon.h:5783
1429 {*neon_vswpv4hi}
(expr_list:REG_UNUSED (reg:V4HI 54 d19 [ D.16372+8 ])
(nil)))
(insn 27 73 31 4 (set (reg:V4SI 52 d18 [orig:118 D.16373 ] [118])
(unspec:V4SI [
(reg:V4HI 52 d18 [orig:115 D.16372 ] [115])
(const_int 1 [0x1])
] UNSPEC_VMOVL))
/work/rearnsha/scratch/gnu/gcc/trunk/gcc/include/arm_neon.h:6183 1470
{neon_vmovlv4hi}
(nil))
and regcprop substitues d19 for d18 in insn 27, missing the fact that insn 73
is swapping the two values (thus clobbering the old d19 value). Giving:
(insn 27 73 31 4 (set (reg:V4SI 52 d18 [orig:118 D.16373 ] [118])
(unspec:V4SI [
(reg:V4HI 54 d19 [orig:115 D.16372 ] [115])
(const_int 1 [0x1])
] UNSPEC_VMOVL))
/work/rearnsha/scratch/gnu/gcc/trunk/gcc/include/arm_neon.h:6183 1470
{neon_vmovlv4hi}
(nil))
next prev parent reply other threads:[~2013-10-04 17:29 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-08-17 15:28 [Bug target/54300] New: [4.7/4.8 " eric.batut at allegorithmic dot com
2012-08-18 8:12 ` [Bug target/54300] " rguenth at gcc dot gnu.org
2012-08-20 16:11 ` eric.batut at allegorithmic dot com
2012-09-07 10:33 ` rguenth at gcc dot gnu.org
2012-09-20 10:26 ` jakub at gcc dot gnu.org
2012-10-25 12:56 ` eric.batut at allegorithmic dot com
2012-10-25 23:03 ` steven at gcc dot gnu.org
2012-12-03 15:42 ` rguenth at gcc dot gnu.org
2013-01-10 22:19 ` [Bug target/54300] [4.7 " pinskia at gcc dot gnu.org
2013-01-11 10:42 ` eric.batut at allegorithmic dot com
2013-04-11 8:00 ` rguenth at gcc dot gnu.org
2013-08-20 16:32 ` eric.batut at allegorithmic dot com
2013-10-04 17:29 ` rearnsha at gcc dot gnu.org [this message]
2013-10-08 9:36 ` [Bug rtl-optimization/54300] [4.7, 4.8, 4.9 Regression] regcprop incorrectly looks through parallel register swap operation ebotcazou at gcc dot gnu.org
2013-10-08 9:47 ` rearnsha at gcc dot gnu.org
2013-10-08 10:54 ` ebotcazou at gcc dot gnu.org
2013-11-20 13:55 ` rearnsha at gcc dot gnu.org
2013-12-05 9:56 ` [Bug rtl-optimization/54300] [4.7, 4.8 " steven at gcc dot gnu.org
2013-12-09 14:54 ` rearnsha at gcc dot gnu.org
2014-01-09 15:19 ` rearnsha at gcc dot gnu.org
2014-01-10 16:55 ` rearnsha at gcc dot gnu.org
2014-01-10 16:56 ` rearnsha at gcc dot gnu.org
2014-08-29 1:27 ` gregory.0xf0 at gmail dot com
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