[Mlir-commits] [mlir] [MLIR][Presburger] Fix Gaussian elimination (PR #164437)

[Arjun P]

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@@ -1112,15 +1112,28 @@ unsigned IntegerRelation::gaussianEliminateVars(unsigned posStart,
   return posLimit - posStart;
 }
 
+static std::optional<unsigned>
+findEqualityWithNonZeroAfterRow(IntegerRelation &rel, unsigned fromRow,
+                                unsigned colIdx) {
+  assert(fromRow < rel.getNumVars() && colIdx < rel.getNumCols() &&
+         "position out of bounds");
+  for (unsigned rowIdx = fromRow; rowIdx < rel.getNumEqualities(); ++rowIdx) {
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Superty wrote:

in LLVM we are supposed to write this as 

`for (unsigned rowIdx = fromRow, e = rel.getNumEqualities(); rowIdx < e; ++rowIdx)`

https://llvm.org/docs/CodingStandards.html#don-t-evaluate-end-every-time-through-a-loop

https://github.com/llvm/llvm-project/pull/164437