Hi Thomas,
On 24/10/16 09:04, Thomas Preudhomme wrote:
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
<snip>
else
- return \"lda<sync_sfx>%?\\t%0, %1\";
+ {
+ if (TARGET_THUMB1)
+ return \"lda<sync_sfx>\\t%0, %1\";
+ else
+ return \"lda<sync_sfx>%?\\t%0, %1\";
+ }
}
- [(set_attr "predicable" "yes")
+ [(set_attr "arch" "32,v8mb,any")
+ (set_attr "predicable" "yes")
(set_attr "predicable_short_it" "no")])
Please set the predicable attribute to "no" for the v8mb alternative.
It wouldn't change any functionality as the ifcvt pass for conditional execution
won't run for ARMv8-M Baseline but it's better to be explicit for documentation
purposes.
Same for the other patterns where you add new v8mb alternatives.