[Bug tree-optimization/106458] [12/13 Regression] glibc's malloc/tst-scratch_buffer.c test is miscompiled with gcc-12
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106458 Andrew Pinski changed: What|Removed |Added Resolution|FIXED |MOVED
[Bug tree-optimization/106458] [12/13 Regression] glibc's malloc/tst-scratch_buffer.c test is miscompiled with gcc-12
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106458 John David Anglin changed: What|Removed |Added Status|UNCONFIRMED |RESOLVED Resolution|--- |FIXED --- Comment #17 from John David Anglin --- glibc issue: commit 8c77e26ba8b360c851b2b9485bb4431aacc51ad1 Author: Szabolcs Nagy Date: Tue Oct 11 13:23:25 2022 +0100 Remove unused scratch_buffer_dupfree Turns out scratch_buffer_dupfree internal API was unused since commit ef074bf0dccf493a5e8e21f71d9e7972ea9f stdlib: Simplify buffer management in canonicalize And the related test in malloc/tst-scratch_buffer had issues so it's better to remove it completely.
[Bug tree-optimization/106458] [12/13 Regression] glibc's malloc/tst-scratch_buffer.c test is miscompiled with gcc-12
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106458 Richard Biener changed: What|Removed |Added Target Milestone|12.2|12.3 --- Comment #16 from Richard Biener --- GCC 12.2 is being released, retargeting bugs to GCC 12.3.
[Bug tree-optimization/106458] [12/13 Regression] glibc's malloc/tst-scratch_buffer.c test is miscompiled with gcc-12
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106458
--- Comment #15 from dave.anglin at bell dot net ---
On 2022-08-10 9:30 a.m., rguenth at gcc dot gnu.org wrote:
> hen I try with a cc1 cross I see
>
>> ./cc1 -quiet t.i -fpreprocessed -O2 -g -std=gnu11 -fgnu89-inline
>> -fmerge-all-constants -frounding-math -fno-stack-protector -fno-common
>> -fmath-errno-fno-pie -fopt-info-vec
> and nothing actually vectorized. Besides the PRE there seems to be a missed
> DSE at the end (when vectorization is enabled as after the change):
>
> # DEBUG BEGIN_STMT
> memset (&buf.__space.__c, 64, 1024);
> # DEBUG BEGIN_STMT
> + sizes[0] = 16;
> sizes[1] = 1024;
> sizes[2] = 1040;
>
> otherwise I see nothing suspicious in differences in .optimized when
> comparing -fdump-tree-optimized with/without -fno-tree-vectorize.
>
I'm not sure what's going on with the sizes[0] statement but the main
difference in .optimize with and without pre
seems to be in the handling of the old_length variable in do_test:
Removing basic block 86
int do_test ()
{
- unsigned int ivtmp.23;
- size_t old_length;
+ unsigned int ivtmp.28;
void * r;
void * c;
size_t l;
[Bug tree-optimization/106458] [12/13 Regression] glibc's malloc/tst-scratch_buffer.c test is miscompiled with gcc-12
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106458 --- Comment #14 from dave.anglin at bell dot net --- On 2022-08-10 1:38 p.m., dave.anglin at bell dot net wrote: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106458 > > --- Comment #13 from dave.anglin at bell dot net --- > On 2022-08-10 9:30 a.m., rguenth at gcc dot gnu.org wrote: >> You could try if -fno-tree-pre reproduces it also before the change. > It doesn't. But the test does not fail after the change with -fno-tree-pre.
[Bug tree-optimization/106458] [12/13 Regression] glibc's malloc/tst-scratch_buffer.c test is miscompiled with gcc-12
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106458 --- Comment #13 from dave.anglin at bell dot net --- On 2022-08-10 9:30 a.m., rguenth at gcc dot gnu.org wrote: > You could try if -fno-tree-pre reproduces it also before the change. It doesn't.
[Bug tree-optimization/106458] [12/13 Regression] glibc's malloc/tst-scratch_buffer.c test is miscompiled with gcc-12
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106458 --- Comment #12 from dave.anglin at bell dot net --- On 2022-08-10 9:30 a.m., rguenth at gcc dot gnu.org wrote: > When I try with a cc1 cross I see > >> ./cc1 -quiet t.i -fpreprocessed -O2 -g -std=gnu11 -fgnu89-inline >> -fmerge-all-constants -frounding-math -fno-stack-protector -fno-common >> -fmath-errno-fno-pie -fopt-info-vec > and nothing actually vectorized. Besides the PRE there seems to be a missed > DSE at the end (when vectorization is enabled as after the change): > > # DEBUG BEGIN_STMT > memset (&buf.__space.__c, 64, 1024); > # DEBUG BEGIN_STMT > + sizes[0] = 16; > sizes[1] = 1024; > sizes[2] = 1040; > > otherwise I see nothing suspicious in differences in .optimized when > comparing -fdump-tree-optimized with/without -fno-tree-vectorize. I had tried -fno-tree-vectorize and it made no difference to the test. So, it seems GCC is miscompiled with the -ftree-vectorize change. I thought of building GCC with -fno-tree-vectorize as a test. > > You could try if -fno-tree-pre reproduces it also before the change. > Will try.
[Bug tree-optimization/106458] [12/13 Regression] glibc's malloc/tst-scratch_buffer.c test is miscompiled with gcc-12
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106458 --- Comment #11 from Richard Biener --- The dump difference is easily explained by taming PRE when -ftree-vectorize is on, it's not a "real" difference. When I try with a cc1 cross I see > ./cc1 -quiet t.i -fpreprocessed -O2 -g -std=gnu11 -fgnu89-inline > -fmerge-all-constants -frounding-math -fno-stack-protector -fno-common > -fmath-errno-fno-pie -fopt-info-vec and nothing actually vectorized. Besides the PRE there seems to be a missed DSE at the end (when vectorization is enabled as after the change): # DEBUG BEGIN_STMT memset (&buf.__space.__c, 64, 1024); # DEBUG BEGIN_STMT + sizes[0] = 16; sizes[1] = 1024; sizes[2] = 1040; otherwise I see nothing suspicious in differences in .optimized when comparing -fdump-tree-optimized with/without -fno-tree-vectorize. You could try if -fno-tree-pre reproduces it also before the change.
[Bug tree-optimization/106458] [12/13 Regression] glibc's malloc/tst-scratch_buffer.c test is miscompiled with gcc-12
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106458 --- Comment #10 from John David Anglin --- Created attachment 53423 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=53423&action=edit Tree dump
[Bug tree-optimization/106458] [12/13 Regression] glibc's malloc/tst-scratch_buffer.c test is miscompiled with gcc-12
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106458 --- Comment #9 from John David Anglin --- Created attachment 53422 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=53422&action=edit Tree dump First tree dumps that differ.
[Bug tree-optimization/106458] [12/13 Regression] glibc's malloc/tst-scratch_buffer.c test is miscompiled with gcc-12
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106458
John David Anglin changed:
What|Removed |Added
Component|target |tree-optimization
--- Comment #8 from John David Anglin ---
This bug was introduced in the following commit:
dave@atlas:~/gnu/gcc/gcc$ git bisect bad
Bisecting: 0 revisions left to test after this (roughly 0 steps)
[2b8453c401b699ed93c085d0413ab4b5030bcdb8] Enable auto-vectorization at O2 with
very-cheap cost model.
dave@atlas:~/gnu/gcc/gcc$ git log
commit 2b8453c401b699ed93c085d0413ab4b5030bcdb8 (HEAD)
Author: liuhongt
Date: Mon Sep 6 13:48:49 2021 +0800
Enable auto-vectorization at O2 with very-cheap cost model.
gcc/ChangeLog:
* common.opt (ftree-vectorize): Add Var(flag_tree_vectorize).
* doc/invoke.texi (Options That Control Optimization): Update
documents.
* opts.c (default_options_table): Enable auto-vectorization at
O2 with very-cheap cost model.
(finish_options): Use cheap cost model for
explicit -ftree{,-loop}-vectorize.
gcc/testsuite/ChangeLog:
* c-c++-common/Wstringop-overflow-2.c: Adjust testcase.
* g++.dg/tree-ssa/pr81408.C: Ditto.
* g++.dg/warn/Wuninitialized-13.C: Ditto.
* gcc.dg/Warray-bounds-51.c: Ditto.
* gcc.dg/Warray-parameter-3.c: Ditto.
dave@atlas:~/gnu/gcc/gcc$ git bisect bad
2b8453c401b699ed93c085d0413ab4b5030bcdb8 is the first bad commit
commit 2b8453c401b699ed93c085d0413ab4b5030bcdb8
Author: liuhongt
Date: Mon Sep 6 13:48:49 2021 +0800
Enable auto-vectorization at O2 with very-cheap cost model.
gcc/ChangeLog:
* common.opt (ftree-vectorize): Add Var(flag_tree_vectorize).
* doc/invoke.texi (Options That Control Optimization): Update
documents.
* opts.c (default_options_table): Enable auto-vectorization at
O2 with very-cheap cost model.
(finish_options): Use cheap cost model for
explicit -ftree{,-loop}-vectorize.
gcc/testsuite/ChangeLog:
* c-c++-common/Wstringop-overflow-2.c: Adjust testcase.
* g++.dg/tree-ssa/pr81408.C: Ditto.
* g++.dg/warn/Wuninitialized-13.C: Ditto.
* gcc.dg/Warray-bounds-51.c: Ditto.
* gcc.dg/Warray-parameter-3.c: Ditto.
* gcc.dg/Wstringop-overflow-14.c: Ditto.
* gcc.dg/Wstringop-overflow-21.c: Ditto.
* gcc.dg/Wstringop-overflow-68.c: Ditto.
* gcc.dg/Wstringop-overflow-76.c: Ditto.
* gcc.dg/gomp/pr46032-2.c: Ditto.
* gcc.dg/gomp/pr46032-3.c: Ditto.
* gcc.dg/gomp/simd-2.c: Ditto.
* gcc.dg/gomp/simd-3.c: Ditto.
* gcc.dg/graphite/fuse-1.c: Ditto.
* gcc.dg/pr67089-6.c: Ditto.
* gcc.dg/pr82929-2.c: Ditto.
* gcc.dg/pr82929.c: Ditto.
* gcc.dg/store_merging_1.c: Ditto.
* gcc.dg/store_merging_11.c: Ditto.
* gcc.dg/store_merging_13.c: Ditto.
* gcc.dg/store_merging_15.c: Ditto.
* gcc.dg/store_merging_16.c: Ditto.
* gcc.dg/store_merging_19.c: Ditto.
* gcc.dg/store_merging_24.c: Ditto.
* gcc.dg/store_merging_25.c: Ditto.
* gcc.dg/store_merging_28.c: Ditto.
* gcc.dg/store_merging_30.c: Ditto.
* gcc.dg/store_merging_5.c: Ditto.
* gcc.dg/store_merging_7.c: Ditto.
* gcc.dg/store_merging_8.c: Ditto.
* gcc.dg/strlenopt-85.c: Ditto.
* gcc.dg/tree-ssa/dump-6.c: Ditto.
* gcc.dg/tree-ssa/pr19210-1.c: Ditto.
* gcc.dg/tree-ssa/pr47059.c: Ditto.
* gcc.dg/tree-ssa/pr86017.c: Ditto.
* gcc.dg/tree-ssa/pr91482.c: Ditto.
* gcc.dg/tree-ssa/predcom-1.c: Ditto.
* gcc.dg/tree-ssa/predcom-dse-3.c: Ditto.
* gcc.dg/tree-ssa/prefetch-3.c: Ditto.
* gcc.dg/tree-ssa/prefetch-6.c: Ditto.
* gcc.dg/tree-ssa/prefetch-8.c: Ditto.
* gcc.dg/tree-ssa/prefetch-9.c: Ditto.
* gcc.dg/tree-ssa/ssa-dse-18.c: Ditto.
* gcc.dg/tree-ssa/ssa-dse-19.c: Ditto.
* gcc.dg/uninit-40.c: Ditto.
* gcc.dg/unroll-7.c: Ditto.
* gcc.misc-tests/help.exp: Ditto.
* gcc.target/i386/avx512vpopcntdqvl-vpopcntd-1.c: Ditto.
* gcc.target/i386/pr34012.c: Ditto.
* gcc.target/i386/pr49781-1.c: Ditto.
* gcc.target/i386/pr95798-1.c: Ditto.
* gcc.target/i386/pr95798-2.c: Ditto.
* gfortran.dg/pr77498.f: Ditto.
gcc/common.opt | 2 +-
gcc/doc/invoke.texi | 8
gcc/opts.c | 16 +++
