[mlir] NFC: remove IntegerValueSet / MutableIntegerSet

[bondhugula]

Summary

• these are unused and really not needed now given flat affine constraints

Signed-off-by: Uday Bondhugula <[e-mail]>

[bondhugula]

@mehdi_amini, could you please commit this for me? Thanks.

[nicolasvasilache]

Good to see these go, I remember flagging them for removal in the very first month :)
Thanks for the cleanup Uday!

[bondhugula]

In D75792#1911799, @nicolasvasilache wrote:

Good to see these go, I remember flagging them for removal in the very first month :)

Yes, along with FlatAffineConstraints and AffineValueMap as well, all of which weren't implemented yet then. :-) This isn't needed because flat affine constraints already provides a throwaway structure for what was intended with MutableIntegerSet.

Thanks for the cleanup Uday!

Could you please commit this for me? Thanks!

mlir/include/mlir/Analysis/AffineStructures.h

 class AffineValueMap;
 class IntegerSet;
 class MLIRContext;
 class Value;
 class HyperRectangularSet;
 class MemRefType;
 struct MutableAffineMap;
 
-/// A mutable integer set. Its affine expressions are however unique.
-struct MutableIntegerSet {
-public:
-  MutableIntegerSet(IntegerSet set, MLIRContext *context);
-
-  /// Create a universal set (no constraints).
-  MutableIntegerSet(unsigned numDims, unsigned numSymbols,
-                    MLIRContext *context);
-
-  unsigned getNumDims() const { return numDims; }
-  unsigned getNumSymbols() const { return numSymbols; }
-  unsigned getNumConstraints() const { return constraints.size(); }
-
-  void clear() {
-    constraints.clear();
-    eqFlags.clear();
-  }
-
-private:
-  unsigned numDims;
-  unsigned numSymbols;
-
-  SmallVector<AffineExpr, 8> constraints;
-  SmallVector<bool, 8> eqFlags;
-};
-
-/// An IntegerValueSet is an integer set plus its operands.
-// Both, the integer set being pointed to and the operands can change during
-// analysis, simplification, and transformation.
-class IntegerValueSet {
-  /// Constructs an integer value set from an affine value map.
-  // This will lead to a single equality in 'set'.
-  explicit IntegerValueSet(const AffineValueMap &avm);
-
-  /// Returns true if this integer set is determined to be empty. Emptiness is
-  /// checked by by eliminating identifiers successively (through either
-  /// Gaussian or Fourier-Motzkin) while using the GCD test and a trivial
-  /// invalid constraint check. Returns 'true' if the constraint system is found
-  /// to be empty; false otherwise. This method is exact for rational spaces but
-  /// not integer spaces - thus, if it returns true, the set is provably integer
-  /// empty as well, but if it returns false, it doesn't necessarily mean an
-  /// integer point exists in it. This method also returns false where an
-  /// explosion of constraints is detected - due to the super-exponential
-  /// worse-case complexity of Fourier-Motzkin elimination (rare for realistic
-  /// problem cases but possible for artificial adversarial or improperly
-  // constructed ones), this method returns false conservatively.
-  bool isEmpty() const;
-
-  bool getNumDims() const { return set.getNumDims(); }
-  bool getNumSymbols() const { return set.getNumSymbols(); }
-
-private:
-  // The set pointed to may itself change unlike in IR structures like
-  // 'AffineCondition'.
-  MutableIntegerSet set;
-  /// The SSA operands binding to the dim's and symbols of 'set'.
-  SmallVector<Value, 4> operands;
-};
-
 /// A flat list of affine equalities and inequalities in the form.
 /// Inequality: c_0*x_0 + c_1*x_1 + .... + c_{n-1}*x_{n-1} >= 0
 /// Equality: c_0*x_0 + c_1*x_1 + .... + c_{n-1}*x_{n-1} == 0
 ///
 /// FlatAffineConstraints stores coefficients in a contiguous buffer (one buffer
 /// for equalities and one for inequalities). The size of each buffer is
 /// numReservedCols * number of inequalities (or equalities). The reserved size
 /// is numReservedCols * numReservedInequalities (or numReservedEqualities). A
public:
   /// these. The constructed system will only include equalities.
   // TODO(bondhugula)
   explicit FlatAffineConstraints(const AffineValueMap &avm);
   explicit FlatAffineConstraints(ArrayRef<const AffineValueMap *> avmRef);
 
   /// Creates an affine constraint system from an IntegerSet.
   explicit FlatAffineConstraints(IntegerSet set);
 
-  /// Create an affine constraint system from an IntegerValueSet.
-  // TODO(bondhugula)
-  explicit FlatAffineConstraints(const IntegerValueSet &set);
-
   FlatAffineConstraints(const FlatAffineConstraints &other);
 
   FlatAffineConstraints(ArrayRef<const AffineValueMap *> avmRef,
                         IntegerSet set);
 
   FlatAffineConstraints(const MutableAffineMap &map);
 
   ~FlatAffineConstraints() {}

mlir/lib/Analysis/AffineStructures.cpp

if (set.getNumConstraints() == 0) {
     localVarCst->reset(set.getNumDims(), set.getNumSymbols());
     return success();
   }
   return ::getFlattenedAffineExprs(set.getConstraints(), set.getNumDims(),
                                    set.getNumSymbols(), flattenedExprs,
                                    localVarCst);
 }
 
-MutableIntegerSet::MutableIntegerSet(IntegerSet set, MLIRContext *context)
-    : numDims(set.getNumDims()), numSymbols(set.getNumSymbols()) {
-  // TODO(bondhugula)
-}
-
-// Universal set.
-MutableIntegerSet::MutableIntegerSet(unsigned numDims, unsigned numSymbols,
-                                     MLIRContext *context)
-    : numDims(numDims), numSymbols(numSymbols) {}
-
 //===----------------------------------------------------------------------===//
 // FlatAffineConstraints.
 //===----------------------------------------------------------------------===//
 
 // Copy constructor.
 FlatAffineConstraints::FlatAffineConstraints(
     const FlatAffineConstraints &other) {
   numReservedCols = other.numReservedCols;