[PATCH] D29064: [MemorySSA] Add invariant.group handling

[Piotr Padlewski via Phabricator via llvm-commits]

Prazek added inline comments.


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Comment at: lib/Transforms/Utils/MemorySSA.cpp:1338
+    // FIXME: This doesn't check if stack if stack empty.
+    // fix it, or write a comment if sentinel exists.
     while (VersionStack.back()->getBlock() == BackBlock)
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george.burgess.iv wrote:
> `VersionStack.push_back(MSSA->getLiveOnEntryDef());` below takes care of that; `liveOnEntryDef` exists in the entry block, so it always dominates everything. :)
> 
> If you'd like to add commentary/asserts, feel free (though preferably as a separate commit).
That's what I thought, which means that !VersionStack.empty() is always true.
I will rewrite this loop later to make it more clear.


https://reviews.llvm.org/D29064