[PATCH] D38262: [AArch64] Use LateSimplifyCFG after expanding atomic operations.

[Balaram Makam via Phabricator via llvm-commits]

bmakam added inline comments.


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Comment at: test/CodeGen/AArch64/cmpxchg-idioms.ll:121
+
+for.cond:                                         ; preds = %if.end, %entry
+  %i.0 = phi i32 [ 2, %entry ], [ %dec, %if.end ]
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efriedma wrote:
> This testcase looks weird because the loop isn't rotated like it normally would be... might not be guess it's not a big deal.
> 
> Please add a short explanation of which CHECK lines are important and why; I assume we're threading a branch somewhere, but it isn't obvious exactly which branch.
The loop wasn't rotated to show the missing simplifyCFG opportunity. This opportunity will be lost when loop is rotated. The preheader block gets simplified after this change and we can elide a branch. Added more CHECK lines and a comment to make it clear.


https://reviews.llvm.org/D38262