[PATCH] D57265: [PM/CC1] Add -f[no-]split-cold-code CC1 options to toggle splitting

[Vedant Kumar via Phabricator via cfe-commits]

vsk added a comment.

@plotfi Sorry this work has stalled, unfortunately I haven't had any bandwidth to drive it forward.

At this point I don't think there are any outstanding concerns with this patch. If anyone is willing to rebase and land it, I would be really grateful. It looks like part of the motivation behind this is removing some downstream diff with the apple/llvm-project fork (as in D89078 <https://reviews.llvm.org/D89078>). I think extra work might be needed to do that, since the HotColdSplitting pass is on-by-default in the Apple fork. Turning the pass on by default on llvm.org could result in a fair amount of fallout, as the pass might interact badly with the machine function splitter (https://lists.llvm.org/pipermail/llvm-dev/2020-August/144012.html). It also hasn't had as much testing on non-Darwin targets (afaik). One solution might be to enable -fsplit-cold-code under -O only for Darwin targets.


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  https://reviews.llvm.org/D57265/new/

https://reviews.llvm.org/D57265