[Mlir-commits] [mlir] [MLIR][Presburger] Implement Matrix::moveColumns (PR #68362)

[llvmlistbot at llvm.org]

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@@ -189,6 +189,22 @@ class Matrix {
   /// invariants satisfied.
   bool hasConsistentState() const;
 
+  /// Move the columns in the source range [srcPos, srcPos + num) to the
+  /// specified destination [dstPos, dstPos + num), while moving the columns
+  /// adjacent to the source range to the left/right of the shifted columns.
+  ///
+  /// When moving the source columns right (i.e. dstPos > srcPos), columns
+  /// that were at positions [0, srcPos) and [dstPos + num, nCols) will stay
+  /// where they are; columns that were at positions [srcPos, srcPos + num) will
+  /// be moved to [dstPos, dstPos + num); and columns that were at positions
+  /// [srcPos + num, dstPos + num) will be moved to [srcPos, dstPos).
+  /// For example, if m = |0 1 2 3 4 5| then
+  /// m.moveColumns(1, 3, 2) will result in m = |0 4 1 2 3 5|; or
+  /// m.moveColumns(1, 2, 4) will result in m = |0 3 4 5 1 2|.
+  ///
+  /// The left shift operation (i.e. dstPos < srcPos) works in a similar way.
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Abhinav271828 wrote:

Would suggest inserting at line 201:
// Equivalently, the ranges [srcPos, srcPos + num) and [srcPos + num, dstPos + num) are swapped.

https://github.com/llvm/llvm-project/pull/68362