[PATCH] D113291: [AggressiveInstCombine] Lower Table Based CTTZ

[Djordje Todorovic via Phabricator via llvm-commits]

djtodoro marked 4 inline comments as done.
djtodoro added inline comments.


================
Comment at: llvm/lib/Transforms/AggressiveInstCombine/AggressiveInstCombine.cpp:476-477
 
+static bool isCTTZTable(const ConstantDataArray &Table, uint64_t Mul,
+                        uint64_t Shift, uint64_t InputBits) {
+  unsigned Length = Table.getNumElements();
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spatel wrote:
> There was a request to put a comment on this function, and I'll second that request. It's not clear why we are counting matches rather than just bailing out on the first mismatch. I think that's because you can construct/recognize a table with unaccessed/undefined elements?
Yes, that is the reason - we are iterating over the elements of the table, so there could be mismatch that we can ignore. A comment is coming.


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https://reviews.llvm.org/D113291