[PATCH] D103614: [PowerPC][AIX][RFC] Generate inlined quadword lock free atomic operations via AtomicExpand

[Kai Luo via Phabricator via llvm-commits]

lkail planned changes to this revision.
lkail added a comment.

In D103614#2797051 <https://reviews.llvm.org/D103614#2797051>, @efriedma wrote:

> I wouldn't recommend using AtomicExpansionKind::LLSC for new code.  It's been a source of problems on other targets that use/used it: most targets have a forward progress rule that imposes restrictions beyond the ll/sc instructions themselves, and normal code generation can violate them.  For example, fast regalloc can insert spills inside the ll/sc loop, or the basic block layout could be rearranged.  I think the only target that hasn't run into issues is Hexagon.

Thanks for these information!


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