[PATCH, ARM 2/7, ping3] Adapt atomic and exclusive load and store to ARMv8-M Baseline

Thomas Preudhomme thomas.preudhomme@foss.arm.com
Mon Oct 24 08:04:00 GMT 2016


Ping?

Best regards,

Thomas

On 14/10/16 14:48, Thomas Preudhomme wrote:
> Ping?
>
> Best regards,
>
> Thomas
>
> On 03/10/16 17:42, Thomas Preudhomme wrote:
>> Ping?
>>
>> Best regards,
>>
>> Thomas
>>
>> On 22/09/16 14:41, Thomas Preudhomme wrote:
>>> Hi,
>>>
>>> This patch is part of a patch series to add support for atomic operations on
>>> ARMv8-M Baseline targets in GCC. This specific patch adapts atomic and exclusive
>>> load and store patterns to the constraints of ARMv8-M Baseline. It consists of
>>> two sets of changes:
>>>
>>> - adding non predicated output templates because ARMv8-M Baseline does not have
>>> IT instruction
>>> - use low registers for ldr/str
>>>
>>> Together these changes require to create 2 new alternatives for atomic_load and
>>> atomic_store: (i) one for relaxed, consume and release memory model (the new Pf
>>> constraint) where ldr/str are used and thus low registers must be used and (ii)
>>> another one for the other memory model where lda/stl are used. These are
>>> separate from the constraint for 32bit targets whose output templates expect
>>> predication.
>>>
>>> ChangeLog entry is as follows:
>>>
>>> *** gcc/ChangeLog ***
>>>
>>> 2016-07-05  Thomas Preud'homme  <thomas.preudhomme@arm.com>
>>>
>>>         * config/arm/constraints.md (Q constraint): Document its use for
>>>         Thumb-1.
>>>         (Pf constraint): New constraint for relaxed, consume or relaxed memory
>>>         models.
>>>         * config/arm/sync.md (atomic_load<mode>): Add new ARMv8-M Baseline only
>>>         alternatives to allow any register when memory model matches Pf and
>>>         thus lda is used, but only low registers otherwise.  Use unpredicated
>>>         output template for Thumb-1 targets.
>>>         (atomic_store<mode>): Likewise for stl.
>>>         (arm_load_exclusive<mode>): Add new ARMv8-M Baseline only alternative
>>>         whose output template does not have predication.
>>>         (arm_load_acquire_exclusive<mode>): Likewise.
>>>         (arm_load_exclusivesi): Likewise.
>>>         (arm_load_acquire_exclusivesi): Likewise.
>>>         (arm_store_release_exclusive<mode>): Likewise.
>>>         (arm_store_exclusive<mode>): Use unpredicated output template for
>>>         Thumb-1 targets.
>>>
>>>
>>> Testing: No code generation difference for ARMv7-A, ARMv7VE and ARMv8-A on all
>>> atomic and synchronization testcases in the testsuite [2]. Patchset was also
>>> bootstrapped with --enable-itm --enable-gomp on ARMv8-A in ARM and Thumb mode at
>>> optimization level -O1 and above [1] without any regression in the testsuite and
>>> no code generation difference in libitm and libgomp.
>>>
>>> Code generation for ARMv8-M Baseline has been manually examined and compared
>>> against ARMv8-A Thumb-2 for the following configuration without finding any
>>> issue:
>>>
>>> gcc.dg/atomic-op-2.c at -Os
>>> gcc.dg/atomic-compare-exchange-2.c at -Os
>>> gcc.dg/atomic-compare-exchange-3.c at -O3
>>>
>>>
>>> Is this ok for trunk?
>>>
>>> Best regards,
>>>
>>> Thomas
>>>
>>> [1] CFLAGS_FOR_TARGET and CXXFLAGS_FOR_TARGET were set to "-O1 -g", "-O3 -g" and
>>> undefined ("-O2 -g")
>>> [2] The exact list is:
>>>
>>> gcc/testsuite/gcc.dg/atomic-compare-exchange-1.c
>>> gcc/testsuite/gcc.dg/atomic-compare-exchange-2.c
>>> gcc/testsuite/gcc.dg/atomic-compare-exchange-3.c
>>> gcc/testsuite/gcc.dg/atomic-exchange-1.c
>>> gcc/testsuite/gcc.dg/atomic-exchange-2.c
>>> gcc/testsuite/gcc.dg/atomic-exchange-3.c
>>> gcc/testsuite/gcc.dg/atomic-fence.c
>>> gcc/testsuite/gcc.dg/atomic-flag.c
>>> gcc/testsuite/gcc.dg/atomic-generic.c
>>> gcc/testsuite/gcc.dg/atomic-generic-aux.c
>>> gcc/testsuite/gcc.dg/atomic-invalid-2.c
>>> gcc/testsuite/gcc.dg/atomic-load-1.c
>>> gcc/testsuite/gcc.dg/atomic-load-2.c
>>> gcc/testsuite/gcc.dg/atomic-load-3.c
>>> gcc/testsuite/gcc.dg/atomic-lockfree.c
>>> gcc/testsuite/gcc.dg/atomic-lockfree-aux.c
>>> gcc/testsuite/gcc.dg/atomic-noinline.c
>>> gcc/testsuite/gcc.dg/atomic-noinline-aux.c
>>> gcc/testsuite/gcc.dg/atomic-op-1.c
>>> gcc/testsuite/gcc.dg/atomic-op-2.c
>>> gcc/testsuite/gcc.dg/atomic-op-3.c
>>> gcc/testsuite/gcc.dg/atomic-op-6.c
>>> gcc/testsuite/gcc.dg/atomic-store-1.c
>>> gcc/testsuite/gcc.dg/atomic-store-2.c
>>> gcc/testsuite/gcc.dg/atomic-store-3.c
>>> gcc/testsuite/g++.dg/ext/atomic-1.C
>>> gcc/testsuite/g++.dg/ext/atomic-2.C
>>> gcc/testsuite/gcc.target/arm/atomic-comp-swap-release-acquire.c
>>> gcc/testsuite/gcc.target/arm/atomic-op-acq_rel.c
>>> gcc/testsuite/gcc.target/arm/atomic-op-acquire.c
>>> gcc/testsuite/gcc.target/arm/atomic-op-char.c
>>> gcc/testsuite/gcc.target/arm/atomic-op-consume.c
>>> gcc/testsuite/gcc.target/arm/atomic-op-int.c
>>> gcc/testsuite/gcc.target/arm/atomic-op-relaxed.c
>>> gcc/testsuite/gcc.target/arm/atomic-op-release.c
>>> gcc/testsuite/gcc.target/arm/atomic-op-seq_cst.c
>>> gcc/testsuite/gcc.target/arm/atomic-op-short.c
>>> gcc/testsuite/gcc.target/arm/atomic_loaddi_1.c
>>> gcc/testsuite/gcc.target/arm/atomic_loaddi_2.c
>>> gcc/testsuite/gcc.target/arm/atomic_loaddi_3.c
>>> gcc/testsuite/gcc.target/arm/atomic_loaddi_4.c
>>> gcc/testsuite/gcc.target/arm/atomic_loaddi_5.c
>>> gcc/testsuite/gcc.target/arm/atomic_loaddi_6.c
>>> gcc/testsuite/gcc.target/arm/atomic_loaddi_7.c
>>> gcc/testsuite/gcc.target/arm/atomic_loaddi_8.c
>>> gcc/testsuite/gcc.target/arm/atomic_loaddi_9.c
>>> gcc/testsuite/gcc.target/arm/sync-1.c
>>> gcc/testsuite/gcc.target/arm/synchronize.c
>>> gcc/testsuite/gcc.target/arm/armv8-sync-comp-swap.c
>>> gcc/testsuite/gcc.target/arm/armv8-sync-op-acquire.c
>>> gcc/testsuite/gcc.target/arm/armv8-sync-op-full.c
>>> gcc/testsuite/gcc.target/arm/armv8-sync-op-release.c
>>> libstdc++-v3/testsuite/29_atomics/atomic/60658.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic/62259.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic/64658.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic/65147.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic/65913.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic/70766.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic/cons/49445.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic/cons/constexpr.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic/cons/copy_list.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic/cons/default.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic/cons/direct_list.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic/cons/single_value.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic/cons/user_pod.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic/operators/51811.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic/operators/56011.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic/operators/integral_assignment.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic/operators/integral_conversion.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic/operators/pointer_partial_void.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic/requirements/base_classes.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic/requirements/compare_exchange_lowering.cc
>>>
>>>
>>> libstdc++-v3/testsuite/29_atomics/atomic/requirements/explicit_instantiation/1.cc
>>>
>>> libstdc++-v3/testsuite/29_atomics/atomic_flag/clear/1.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic_flag/cons/1.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic_flag/cons/56012.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic_flag/cons/aggregate.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic_flag/cons/default.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic_flag/requirements/standard_layout.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic_flag/requirements/trivial.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic_flag/test_and_set/explicit.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic_flag/test_and_set/implicit.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic_integral/60940.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic_integral/65147.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic_integral/cons/constexpr.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic_integral/cons/copy_list.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic_integral/cons/default.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic_integral/cons/direct_list.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic_integral/cons/single_value.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic_integral/operators/bitwise.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic_integral/operators/decrement.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic_integral/operators/increment.cc
>>> libstdc++-v3/testsuite/29_atomics/atomic_integral/operators/integral_assignment.cc
>>>
>>>
>>> libstdc++-v3/testsuite/29_atomics/atomic_integral/operators/integral_conversion.cc
>>>
>>>
>>> libstdc++-v3/testsuite/29_atomics/atomic_integral/requirements/standard_layout.cc
>>>
>>> libstdc++-v3/testsuite/29_atomics/atomic_integral/requirements/trivial.cc
>>> libstdc++-v3/testsuite/29_atomics/headers/atomic/functions_std_c++0x.cc
>>> libstdc++-v3/testsuite/29_atomics/headers/atomic/macros.cc
>>> libstdc++-v3/testsuite/29_atomics/headers/atomic/types_std_c++0x.cc
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 2_adapt_atomic_load_store_v8m_baseline.patch
Type: text/x-patch
Size: 7789 bytes
Desc: not available
URL: <http://gcc.gnu.org/pipermail/gcc-patches/attachments/20161024/2b0ae6cf/attachment.bin>


More information about the Gcc-patches mailing list