[PATCH] D68360: PR41162 Implement LKK remainder and divisibility algorithms

[Jay Foad via Phabricator via llvm-commits]

foad added inline comments.


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Comment at: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:3929
+  }
+
   // If X/C can be simplified by the division-by-constant logic, lower
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Is the "lower X%C to the equivalent of X-X/C*C" code below obsolete now, or is it still required in some cases?


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Comment at: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:3962
+/// Given an ISD::UREM where the divisor is constant,
+/// return a DAG expression that will generate the same comparison result
+/// using only multiplications, additions and shifts.
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Why "same comparison result"? Do you mean "same result"?


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Comment at: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:4061
+/// Given an ISD::SREM where the divisor is constant,
+/// return a DAG expression that will generate the same comparison result
+/// using only multiplications, additions and shifts.
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Ditto.


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https://reviews.llvm.org/D68360