[PATCH] D63948: [SLP] Limit compilation time of look-ahead operand reordering heuristic.

[Vasileios Porpodas via Phabricator via llvm-commits]

vporpo marked an inline comment as done.
vporpo added a comment.

Not sure what kind of test would be suitable for this change. It simply restricts the look-ahead heuristic to not visit more than 2 operands and 2 uses, which is not something visible in the output IR.



================
Comment at: llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp:921
+      for (unsigned OpIdx1 = 0,
+                    NumOperands1 = std::min(I1->getNumOperands(),
+                                            LookAheadOperandsBudget.getValue());
----------------
ABataev wrote:
> Do you really need this limit?
Yes, because it could be a call /phi instruction with many operands.


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