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| author | Wilco Dijkstra <wilco.dijkstra@arm.com> | 2022-11-15 14:38:55 +0000 |
|---|---|---|
| committer | Wilco Dijkstra <wilco.dijkstra@arm.com> | 2022-11-15 15:08:33 +0000 |
| commit | d1288d850944f69a795e4ff444a427eba3fec11b (patch) | |
| tree | 0357dd0e95cb2e1825217396f7ff76fe6b1a377b /gcc | |
| parent | 5925f0ec54ab5ed773935eec09a602f58fa0ca2c (diff) | |
| download | gcc-d1288d850944f69a795e4ff444a427eba3fec11b.zip gcc-d1288d850944f69a795e4ff444a427eba3fec11b.tar.gz gcc-d1288d850944f69a795e4ff444a427eba3fec11b.tar.bz2 | |
libatomic: Add support for LSE and LSE2
Add support for AArch64 LSE and LSE2 to libatomic. Disable outline atomics,
and use LSE ifuncs for 1-8 byte atomics and LSE2 ifuncs for 16-byte atomics.
On Neoverse V1, 16-byte atomics are ~4x faster due to avoiding locks.
Note this is safe since we swap all 16-byte atomics using the same ifunc,
so they either use locks or LSE2 atomics, but never a mix. This also improves
ABI compatibility with LLVM: its inlined 16-byte atomics are compatible with
the new libatomic if LSE2 is supported.
libatomic/
* Makefile.in: Regenerated with automake 1.15.1.
* Makefile.am: Add atomic_16.S for AArch64.
* configure.tgt: Disable outline atomics in AArch64 build.
* config/linux/aarch64/atomic_16.S: New file - implementation of
ifuncs for 16-byte atomics.
* config/linux/aarch64/host-config.h: Enable ifuncs, use LSE
(HWCAP_ATOMICS) for 1-8-byte atomics and LSE2 (HWCAP_USCAT) for
16-byte atomics.
Diffstat (limited to 'gcc')
0 files changed, 0 insertions, 0 deletions