diff --git a/mlir/include/mlir/IR/IntegerSet.h b/mlir/include/mlir/IR/IntegerSet.h
--- a/mlir/include/mlir/IR/IntegerSet.h
+++ b/mlir/include/mlir/IR/IntegerSet.h
@@ -11,7 +11,8 @@
 // integer sets in the IR - for 'affine.if' operations and as attributes of
 // other operations. It is typically expected to contain only a handful of
 // affine constraints, and is immutable like an affine map. Integer sets are not
-// unique'd - although affine expressions that make up its equalities and
+// unique'd unless the number of constraints they contain are below a certain
+// threshold - although affine expressions that make up its equalities and
 // inequalities are themselves unique.
 
 // This class is not meant for affine analysis and operations like set
@@ -30,13 +31,14 @@
 
 namespace detail {
 struct IntegerSetStorage;
-}
+} // end namespace detail
 
 class MLIRContext;
 
 /// An integer set representing a conjunction of one or more affine equalities
 /// and inequalities. An integer set in the IR is immutable like the affine map,
-/// but integer sets are not unique'd. The affine expressions that make up the
+/// but integer sets are not unique'd unless the number of constraints in them
+/// is below `kUniquingThreshold`. The affine expressions that make up the
 /// equalities and inequalities of an integer set are themselves unique and are
 /// allocated by the bump pointer allocator.
 class IntegerSet {
@@ -54,7 +56,7 @@
   static IntegerSet getEmptySet(unsigned numDims, unsigned numSymbols,
                                 MLIRContext *context) {
     auto one = getAffineConstantExpr(1, context);
-    /* 1 == 0 */
+    // 1 == 0.
     return get(numDims, numSymbols, one, true);
   }
 
@@ -127,14 +129,14 @@
 } // end namespace mlir
 namespace llvm {
 
-// IntegerSet hash just like pointers
+// IntegerSet hash just like pointers.
 template <> struct DenseMapInfo<mlir::IntegerSet> {
   static mlir::IntegerSet getEmptyKey() {
-    auto pointer = llvm::DenseMapInfo<void *>::getEmptyKey();
+    auto *pointer = llvm::DenseMapInfo<void *>::getEmptyKey();
     return mlir::IntegerSet(static_cast<mlir::IntegerSet::ImplType *>(pointer));
   }
   static mlir::IntegerSet getTombstoneKey() {
-    auto pointer = llvm::DenseMapInfo<void *>::getTombstoneKey();
+    auto *pointer = llvm::DenseMapInfo<void *>::getTombstoneKey();
     return mlir::IntegerSet(static_cast<mlir::IntegerSet::ImplType *>(pointer));
   }
   static unsigned getHashValue(mlir::IntegerSet val) {