Revert "[MLIR][Presburger] IntegerPolyhedron: add support for symboli…

…c integer lexmin"

This reverts commit da92f92.

mlir/include/mlir/Analysis/Presburger/IntegerRelation.h

@@ -536,7 +536,6 @@ class IntegerRelation : public PresburgerSpace {
   Matrix inequalities;
 };
 
-struct SymbolicLexMin;
 /// An IntegerPolyhedron is a PresburgerSpace subject to affine
 /// constraints. Affine constraints can be inequalities or equalities in the
 /// form:
@@ -594,28 +593,6 @@ class IntegerPolyhedron : public IntegerRelation {
   /// column position (i.e., not relative to the kind of identifier) of the
   /// first added identifier.
   unsigned insertId(IdKind kind, unsigned pos, unsigned num = 1) override;
-
-  /// Compute the symbolic integer lexmin of the polyhedron.
-  /// This finds, for every assignment to the symbols, the lexicographically
-  /// minimum value attained by the dimensions. For example, the symbolic lexmin
-  /// of the set
-  ///
-  /// (x, y)[a, b, c] : (a <= x, b <= x, x <= c)
-  ///
-  /// can be written as
-  ///
-  /// x = a if b <= a, a <= c
-  /// x = b if a <  b, b <= c
-  ///
-  /// This function is stored in the `lexmin` function in the result.
-  /// Some assignments to the symbols might make the set empty.
-  /// Such points are not part of the function's domain.
-  /// In the above example, this happens when max(a, b) > c.
-  ///
-  /// For some values of the symbols, the lexmin may be unbounded.
-  /// `SymbolicLexMin` stores these parts of the symbolic domain in a separate
-  /// `PresburgerSet`, `unboundedDomain`.
-  SymbolicLexMin findSymbolicIntegerLexMin() const;
 };
 
 } // namespace presburger

mlir/include/mlir/Analysis/Presburger/Matrix.h

@@ -151,9 +151,6 @@ class Matrix {
 
   /// Add an extra row at the bottom of the matrix and return its position.
   unsigned appendExtraRow();
-  /// Same as above, but copy the given elements into the row. The length of
-  /// `elems` must be equal to the number of columns.
-  unsigned appendExtraRow(ArrayRef<int64_t> elems);
 
   /// Print the matrix.
   void print(raw_ostream &os) const;

mlir/include/mlir/Analysis/Presburger/PWMAFunction.h

@@ -106,11 +106,6 @@ class MultiAffineFunction : protected IntegerPolyhedron {
   /// outside the domain, an empty optional is returned.
   Optional<SmallVector<int64_t, 8>> valueAt(ArrayRef<int64_t> point) const;
 
-  /// Truncate the output dimensions to the first `count` dimensions.
-  ///
-  /// TODO: refactor so that this can be accomplished through removeIdRange.
-  void truncateOutput(unsigned count);
-
   void print(raw_ostream &os) const;
   void dump() const;
 
@@ -170,11 +165,6 @@ class PWMAFunction : public PresburgerSpace {
   /// value at every point in the domain.
   bool isEqual(const PWMAFunction &other) const;
 
-  /// Truncate the output dimensions to the first `count` dimensions.
-  ///
-  /// TODO: refactor so that this can be accomplished through removeIdRange.
-  void truncateOutput(unsigned count);
-
   void print(raw_ostream &os) const;
   void dump() const;
 

mlir/lib/Analysis/Presburger/IntegerRelation.cpp

@@ -14,7 +14,6 @@
 
 #include "mlir/Analysis/Presburger/IntegerRelation.h"
 #include "mlir/Analysis/Presburger/LinearTransform.h"
-#include "mlir/Analysis/Presburger/PWMAFunction.h"
 #include "mlir/Analysis/Presburger/PresburgerRelation.h"
 #include "mlir/Analysis/Presburger/Simplex.h"
 #include "mlir/Analysis/Presburger/Utils.h"
@@ -146,21 +145,6 @@ void IntegerRelation::truncate(const CountsSnapshot &counts) {
   removeEqualityRange(counts.getNumEqs(), getNumEqualities());
 }
 
-SymbolicLexMin IntegerPolyhedron::findSymbolicIntegerLexMin() const {
-  // Compute the symbolic lexmin of the dims and locals, with the symbols being
-  // the actual symbols of this set.
-  SymbolicLexMin result =
-      SymbolicLexSimplex(
-          *this, PresburgerSpace::getSetSpace(/*numDims=*/getNumSymbolIds()))
-          .computeSymbolicIntegerLexMin();
-
-  // We want to return only the lexmin over the dims, so strip the locals from
-  // the computed lexmin.
-  result.lexmin.truncateOutput(result.lexmin.getNumOutputs() -
-                               getNumLocalIds());
-  return result;
-}
-
 unsigned IntegerRelation::insertId(IdKind kind, unsigned pos, unsigned num) {
   assert(pos <= getNumIdKind(kind));
 

mlir/lib/Analysis/Presburger/Matrix.cpp

@@ -66,14 +66,6 @@ unsigned Matrix::appendExtraRow() {
   return nRows - 1;
 }
 
-unsigned Matrix::appendExtraRow(ArrayRef<int64_t> elems) {
-  assert(elems.size() == nColumns && "elems must match row length!");
-  unsigned row = appendExtraRow();
-  for (unsigned col = 0; col < nColumns; ++col)
-    at(row, col) = elems[col];
-  return row;
-}
-
 void Matrix::resizeHorizontally(unsigned newNColumns) {
   if (newNColumns < nColumns)
     removeColumns(newNColumns, nColumns - newNColumns);

mlir/lib/Analysis/Presburger/PWMAFunction.cpp

@@ -114,18 +114,6 @@ void MultiAffineFunction::eliminateRedundantLocalId(unsigned posA,
   IntegerPolyhedron::eliminateRedundantLocalId(posA, posB);
 }
 
-void MultiAffineFunction::truncateOutput(unsigned count) {
-  assert(count <= output.getNumRows());
-  output.resizeVertically(count);
-}
-
-void PWMAFunction::truncateOutput(unsigned count) {
-  assert(count <= numOutputs);
-  for (MultiAffineFunction &piece : pieces)
-    piece.truncateOutput(count);
-  numOutputs = count;
-}
-
 bool MultiAffineFunction::isEqualWhereDomainsOverlap(
     MultiAffineFunction other) const {
   if (!isSpaceCompatible(other))