Hi Kyrill, Thanks for pointing out the two missing bug fixes. Please see attached all the back-ported patches. All the patches from trunk applied cleanly with no conflicts (except for the ChangeLog files) to the gcc-9 branch. An up to date gcc-9 branch on which I applied the attached patches has passed bootstrap on aarch64-linux (Graviton2 with 64 N1 cores) and make check with no extra fails. Kyrill, could you please commit the attached patches to the gcc-9 branch?
As we still don't have a copyright assignment on file, would it be possible for
ARM to finish the backport to the gcc-8 branch of these patches and the atomics
cleanup patches mentioned below?
I did a `git log config/aarch64/atomics.md` and there is a follow-up patch to
the atomics cleanup patches:
commit e21679a8bb17aac603b8704891e60ac502200629
Author: Jakub Jelinek <ja...@redhat.com>
Date: Wed Nov 21 17:41:03 2018 +0100
re PR target/87839 (ICE in final_scan_insn_1, at final.c:3070)
PR target/87839
* config/aarch64/atomics.md (@aarch64_compare_and_swap<mode>): Use
rIJ constraint for aarch64_plus_operand rather than rn.
* gcc.target/aarch64/pr87839.c: New test.
From-SVN: r266346
That is fixing code modified in this cleanup patch:
commit d400fda3a8c3330f77eb9d51874f5482d3819a9f
Author: Richard Henderson <richard.hender...@linaro.org>
Date: Wed Oct 31 09:42:39 2018 +0000
aarch64: Improve cas generation
Thanks,
Sebastian
On 3/11/20, 5:11 AM, "Kyrill Tkachov" <kyrylo.tkac...@foss.arm.com> wrote:
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Hi Sebastian,
On 3/9/20 9:47 PM, Pop, Sebastian wrote:
> Hi,
>
> Please see attached the patches to add -moutline-atomics to the gcc-9
branch.
> Tested on graviton2 aarch64-linux with bootstrap and
> `make check` passes with no new fails.
> Tested `make check` on glibc built with gcc-9 with and without
"-moutline-atomics"
> and CFLAGS=" -O2 -g -fno-stack-protector -U_FORTIFY_SOURCE".
>
> Ok to commit to gcc-9 branch?
Since this feature enables backwards-compatible deployment of LSE
atomics, I'd support that.
That is okay with me in principle after GCC 9.3 is released (the branch
is currently frozen).
However, there have been a few follow-up patches to fix some bugs
revealed by testing.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91833
and
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91834
come to mind.
Can you please make sure the fixes for those are included as well?
>
> Does this mechanical `git am *.patch` require a copyright assignment?
> I am still working with my employer on getting the FSF assignment signed.
>
> Thanks,
> Sebastian
>
> PS: For gcc-8 backports there are 5 cleanup and improvement patches
> that are needed for -moutline-atomics patches to apply cleanly.
> Should these patches be back-ported in the same time as the flag patches,
> or should I update the patches to apply to the older code base?
Hmm... normally I'd be for them. In this case I'd want to make sure that
there aren't any fallout fixes that we're missing.
Did these patches have any bug reports against them?
Thanks,
Kyrill
> Here is the list of the extra patches:
>
> From 77f33f44baf24c22848197aa80962c003dd7b3e2 Mon Sep 17 00:00:00 2001
> From: Richard Henderson <richard.hender...@linaro.org>
> Date: Wed, 31 Oct 2018 09:29:29 +0000
> Subject: [PATCH] aarch64: Simplify LSE cas generation
>
> The cas insn is a single insn, and if expanded properly need not
> be split after reload. Use the proper inputs for the insn.
>
> * config/aarch64/aarch64.c (aarch64_expand_compare_and_swap):
> Force oldval into the rval register for TARGET_LSE; emit the
compare
> during initial expansion so that it may be deleted if unused.
> (aarch64_gen_atomic_cas): Remove.
> * config/aarch64/atomics.md
(@aarch64_compare_and_swap<SHORT>_lse):
> Change =&r to +r for operand 0; use match_dup for operand 2;
> remove is_weak and mod_f operands as unused. Drop the split
> and merge with...
> (@aarch64_atomic_cas<SHORT>): ... this pattern's output; remove.
> (@aarch64_compare_and_swap<GPI>_lse): Similarly.
> (@aarch64_atomic_cas<GPI>): Similarly.
>
> From-SVN: r265656
>
> From d400fda3a8c3330f77eb9d51874f5482d3819a9f Mon Sep 17 00:00:00 2001
> From: Richard Henderson <richard.hender...@linaro.org>
> Date: Wed, 31 Oct 2018 09:42:39 +0000
> Subject: [PATCH] aarch64: Improve cas generation
>
> Do not zero-extend the input to the cas for subword operations;
> instead, use the appropriate zero-extending compare insns.
> Correct the predicates and constraints for immediate expected operand.
>
> * config/aarch64/aarch64.c (aarch64_gen_compare_reg_maybe_ze):
New.
> (aarch64_split_compare_and_swap): Use it.
> (aarch64_expand_compare_and_swap): Likewise. Remove
convert_modes;
> test oldval against the proper predicate.
> * config/aarch64/atomics.md (@atomic_compare_and_swap<ALLI>):
> Use nonmemory_operand for expected.
> (cas_short_expected_pred): New.
> (@aarch64_compare_and_swap<SHORT>): Use it; use "rn" not "rI" to
match.
> (@aarch64_compare_and_swap<GPI>): Use "rn" not "rI" for expected.
> * config/aarch64/predicates.md (aarch64_plushi_immediate): New.
> (aarch64_plushi_operand): New.
>
> From-SVN: r265657
>
> From 8f5603d363a4e0453d2c38c7103aeb0bdca85c4e Mon Sep 17 00:00:00 2001
> From: Richard Henderson <richard.hender...@linaro.org>
> Date: Wed, 31 Oct 2018 09:47:21 +0000
> Subject: [PATCH] aarch64: Improve swp generation
>
> Allow zero as an input; fix constraints; avoid unnecessary split.
>
> * config/aarch64/aarch64.c (aarch64_emit_atomic_swap): Remove.
> (aarch64_gen_atomic_ldop): Don't call it.
> * config/aarch64/atomics.md (atomic_exchange<ALLI>):
> Use aarch64_reg_or_zero.
> (aarch64_atomic_exchange<ALLI>): Likewise.
> (aarch64_atomic_exchange<ALLI>_lse): Remove split; remove & from
> operand 0; use aarch64_reg_or_zero for input; merge ...
> (@aarch64_atomic_swp<ALLI>): ... this and remove.
>
> From-SVN: r265659
>
> From 7803ec5ee2a547043fb6708a08ddb1361ba91202 Mon Sep 17 00:00:00 2001
> From: Richard Henderson <richard.hender...@linaro.org>
> Date: Wed, 31 Oct 2018 09:58:48 +0000
> Subject: [PATCH] aarch64: Improve atomic-op lse generation
>
> Fix constraints; avoid unnecessary split. Drop the use of the atomic_op
> iterator in favor of the ATOMIC_LDOP iterator; this is simplier and more
> logical for ldclr aka bic.
>
> * config/aarch64/aarch64.c (aarch64_emit_bic): Remove.
> (aarch64_atomic_ldop_supported_p): Remove.
> (aarch64_gen_atomic_ldop): Remove.
> * config/aarch64/atomic.md (atomic_<atomic_optab><ALLI>):
> Fully expand LSE operations here.
> (atomic_fetch_<atomic_optab><ALLI>): Likewise.
> (atomic_<atomic_optab>_fetch<ALLI>): Likewise.
> (aarch64_atomic_<ATOMIC_LDOP><ALLI>_lse): Drop atomic_op iterator
> and use ATOMIC_LDOP instead; use register_operand for the input;
> drop the split and emit insns directly.
> (aarch64_atomic_fetch_<ATOMIC_LDOP><ALLI>_lse): Likewise.
> (aarch64_atomic_<atomic_op>_fetch<ALLI>_lse): Remove.
> (@aarch64_atomic_load<ATOMIC_LDOP><ALLI>): Remove.
>
> From-SVN: r265660
>
> From 53de1ea800db54b47290d578c43892799b66c8dc Mon Sep 17 00:00:00 2001
> From: Richard Henderson <richard.hender...@linaro.org>
> Date: Wed, 31 Oct 2018 23:11:22 +0000
> Subject: [PATCH] aarch64: Remove early clobber from ATOMIC_LDOP scratch
>
> * config/aarch64/atomics.md
(aarch64_atomic_<ATOMIC_LDOP><ALLI>_lse):
> The scratch register need not be early-clobber. Document the
reason
> why we cannot use ST<OP>.
>
> From-SVN: r265703
>
>
>
>
>
> On 2/27/20, 12:06 PM, "Kyrill Tkachov" <kyrylo.tkac...@foss.arm.com>
wrote:
>
> Hi Sebastian,
>
> On 2/27/20 4:53 PM, Pop, Sebastian wrote:
> >
> > Hi,
> >
> > is somebody already working on backporting -moutline-atomics to gcc
> > 8.x and 9.x branches?
> >
> I'm not aware of such work going on.
>
> Thanks,
>
> Kyrill
>
> > Thanks,
> >
> > Sebastian
> >
>
>
0001-aarch64-Extend-R-for-integer-registers.patch
Description: 0001-aarch64-Extend-R-for-integer-registers.patch
0002-aarch64-Implement-TImode-compare-and-swap.patch
Description: 0002-aarch64-Implement-TImode-compare-and-swap.patch
0003-aarch64-Tidy-aarch64_split_compare_and_swap.patch
Description: 0003-aarch64-Tidy-aarch64_split_compare_and_swap.patch
0004-aarch64-Add-out-of-line-functions-for-LSE-atomics.patch
Description: 0004-aarch64-Add-out-of-line-functions-for-LSE-atomics.patch
0005-aarch64-Implement-moutline-atomics.patch
Description: 0005-aarch64-Implement-moutline-atomics.patch
0006-Fix-shrinkwrapping-interactions-with-atomics-PR92692.patch
Description: 0006-Fix-shrinkwrapping-interactions-with-atomics-PR92692.patch
0007-aarch64-Fix-store-exclusive-in-load-operate-LSE-help.patch
Description: 0007-aarch64-Fix-store-exclusive-in-load-operate-LSE-help.patch
0008-aarch64-Configure-for-sys-auxv.h-in-libgcc-for-lse-i.patch
Description: 0008-aarch64-Configure-for-sys-auxv.h-in-libgcc-for-lse-i.patch
