Instruction scheduling: do not reorder atomic loads#12248
Merged
xavierleroy merged 4 commits intoocaml:trunkfrom May 16, 2023
Merged
Instruction scheduling: do not reorder atomic loads#12248xavierleroy merged 4 commits intoocaml:trunkfrom
xavierleroy merged 4 commits intoocaml:trunkfrom
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Co-authored-by: Nicolás Ojeda Bär <n.oje.bar@gmail.com>
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As noticed in #11712 (comment), instruction scheduling can reorder atomic loads just like it reorders normal loads, which is incorrect.
This PR fixes the issue trivially, by treating atomic loads like stores, which are never reordered (w.r.t. other stores / atomic loads, and even w.r.t. normal loads).
This fix is mostly cosmetic, since the scheduling pass is currently unused in OCaml 5 (none of the supported target architectures need it), and may very well never be used again in the future.
Fixes: #12216