https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92692
--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> --- (In reply to Wilco from comment #3) > (In reply to Andrew Pinski from comment #2) > > I think this has been a latent bug since revision 243200: > > [AArch64] Separate shrink wrapping hooks implementation > > > > I think aarch64_disqualify_components would be a location which should > > disqualify the Separate for the register 19. > > What is the "exclusives reservation granule" size? It could only fail if the > granule is large and the spill happens to be in the same granule as the stxr. NO "exclusives reservation granule" does not matter here, please read the ARMv8 spec again copied below (B2-142): LoadExcl/StoreExcl loops are guaranteed to make forward progress only if, for any LoadExcl/StoreExcl loop within a single thread of execution, the software meets all of the following conditions: 1 Between the Load-Exclusive and the Store-Exclusive, there are ****no explicit memory accesses****, preloads, direct or indirect System register writes, address translation instructions, cache or TLB maintenance instructions, exception generating instructions, exception returns, or indirect branches. --- CUT ---- ****no explicit memory accesses**** Is a requirement so it does not matter what "exclusives reservation granule" size is really. We had gone through this beforehand with the ARM architectures and made sure that the specifications was worded correctly to the above effect. The wording change happened in 2016.
