https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103762
Bug ID: 103762
Summary: [12 Regression] glibc master branch is miscompiled by
r12-897
Product: gcc
Version: 12.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: middle-end
Assignee: unassigned at gcc dot gnu.org
Reporter: hjl.tools at gmail dot com
CC: luoxhu at cn dot ibm.com
Target Milestone: ---
Target: x86-64
On x86-64, r12-897
commit de56f95afaaa22c67cbeec780921d63e8b34514e
Author: Xionghu Luo <luo...@linux.ibm.com>
Date: Tue May 18 21:34:18 2021 -0500
Run pass_sink_code once more before store_merging
Gimple sink code pass runs quite early, there may be some new
oppertunities exposed by later gimple optmization passes, this patch
runs the sink code pass once more before store_merging. For detailed
discussion, please refer to:
https://gcc.gnu.org/pipermail/gcc-patches/2020-December/562352.html
Tested the SPEC2017 performance on P8LE, 544.nab_r is improved
by 2.43%, but no big changes to other cases, GEOMEAN is improved quite
small with 0.25%.
gcc/ChangeLog:
2021-05-18 Xionghu Luo <luo...@linux.ibm.com>
* passes.def: Add sink_code pass before store_merging.
* tree-ssa-sink.c (pass_sink_code:clone): New.
gcc/testsuite/ChangeLog:
2021-05-18 Xionghu Luo <luo...@linux.ibm.com>
* gcc.dg/tree-ssa/ssa-sink-1.c: Adjust.
* gcc.dg/tree-ssa/ssa-sink-2.c: Ditto.
* gcc.dg/tree-ssa/ssa-sink-3.c: Ditto.
* gcc.dg/tree-ssa/ssa-sink-4.c: Ditto.
* gcc.dg/tree-ssa/ssa-sink-5.c: Ditto.
* gcc.dg/tree-ssa/ssa-sink-6.c: Ditto.
* gcc.dg/tree-ssa/ssa-sink-7.c: Ditto.
* gcc.dg/tree-ssa/ssa-sink-8.c: Ditto.
* gcc.dg/tree-ssa/ssa-sink-9.c: Ditto.
* gcc.dg/tree-ssa/ssa-sink-10.c: Ditto.
* gcc.dg/tree-ssa/ssa-sink-13.c: Ditto.
* gcc.dg/tree-ssa/ssa-sink-14.c: Ditto.
* gcc.dg/tree-ssa/ssa-sink-16.c: Ditto.
* gcc.dg/tree-ssa/ssa-sink-17.c: Ditto.
* gcc.dg/tree-ssa/ssa-sink-18.c: New.
miscompiled glibc master branch:
FAIL: elf/tst-env-setuid
[hjl@gnu-skx-1 build-x86_64-linux]$ env
GCONV_PATH=/export/build/gnu/tools-build/glibc-cet/build-x86_64-linux/iconvdata
LOCPATH=/export/build/gnu/tools-build/glibc-cet/build-x86_64-linux/localedata
LC_ALL=C MALLOC_CHECK_=2 MALLOC_MMAP_THRESHOLD_=4096 LD_HWCAP_MASK=0x1
/export/build/gnu/tools-build/glibc-test/build-x86_64-linux/elf/tst-env-setuid
Segmentation fault (core dumped)
[hjl@gnu-skx-1 build-x86_64-linux]$
(gdb) set env MALLOC_CHECK_=2
(gdb) r --direct
Starting program:
/export/build/gnu/tools-build/glibc-test/build-x86_64-linux/elf/tst-env-setuid
--direct
Program received signal SIGSEGV, Segmentation fault.
0x00007ffff7f67053 in do_tunable_update_val (cur=cur@entry=0xffffefefe7f0,
valp=valp@entry=0x7fffffffdd38, minp=minp@entry=0x0, maxp=maxp@entry=0x0) at
dl-tunables.c:102
102 if (cur->type.type_code == TUNABLE_TYPE_STRING)
(gdb) bt
#0 0x00007ffff7f67053 in do_tunable_update_val (cur=cur@entry=0xffffefefe7f0,
valp=valp@entry=0x7fffffffdd38, minp=minp@entry=0x0, maxp=maxp@entry=0x0)
at dl-tunables.c:102
#1 0x00007ffff7f6733c in tunable_initialize (strval=0x7fffffffefa7 "2",
cur=<optimized out>) at dl-tunables.c:151
#2 __tunables_init (envp=0x7fffffffe058) at dl-tunables.c:349
#3 0x00007ffff7f15f67 in __libc_start_main_impl (main=0x7ffff7f128f0 <main>,
argc=2, argv=0x7fffffffdea8, init=<optimized out>, fini=<optimized out>,
rtld_fini=0x0, stack_end=0x7fffffffde98) at ../csu/libc-start.c:291
#4 0x00007ffff7f129c5 in _start () at ../sysdeps/x86_64/start.S:115
(gdb)
