[flang-commits] [flang] 4b3f251 - [mlir] [dataflow] unify semantics of program point (#110344)

via flang-commits flang-commits at lists.llvm.org
Fri Oct 11 06:59:09 PDT 2024


Author: donald chen
Date: 2024-10-11T21:59:05+08:00
New Revision: 4b3f251bada55cfc20a2c72321fa0bbfd7a759d5

URL: https://github.com/llvm/llvm-project/commit/4b3f251bada55cfc20a2c72321fa0bbfd7a759d5
DIFF: https://github.com/llvm/llvm-project/commit/4b3f251bada55cfc20a2c72321fa0bbfd7a759d5.diff

LOG: [mlir] [dataflow] unify semantics of program point (#110344)

The concept of a 'program point' in the original data flow framework is
ambiguous. It can refer to either an operation or a block itself. This
representation has different interpretations in forward and backward
data-flow analysis. In forward data-flow analysis, the program point of
an operation represents the state after the operation, while in backward
data flow analysis, it represents the state before the operation. When
using forward or backward data-flow analysis, it is crucial to carefully
handle this distinction to ensure correctness.

This patch refactors the definition of program point, unifying the
interpretation of program points in both forward and backward data-flow
analysis.

How to integrate this patch?

For dense forward data-flow analysis and other analysis (except dense
backward data-flow analysis), the program point corresponding to the
original operation can be obtained by `getProgramPointAfter(op)`, and
the program point corresponding to the original block can be obtained by
`getProgramPointBefore(block)`.

For dense backward data-flow analysis, the program point corresponding
to the original operation can be obtained by
`getProgramPointBefore(op)`, and the program point corresponding to the
original block can be obtained by `getProgramPointAfter(block)`.

NOTE: If you need to get the lattice of other data-flow analyses in
dense backward data-flow analysis, you should still use the dense
forward data-flow approach. For example, to get the Executable state of
a block in dense backward data-flow analysis and add the dependency of
the current operation, you should write:

``getOrCreateFor<Executable>(getProgramPointBefore(op),
getProgramPointBefore(block))``

In case above, we use getProgramPointBefore(op) because the analysis we
rely on is dense backward data-flow, and we use
getProgramPointBefore(block) because the lattice we query is the result
of a non-dense backward data flow computation.

related dsscussion:
https://discourse.llvm.org/t/rfc-unify-the-semantics-of-program-points/80671/8
corresponding PSA:
https://discourse.llvm.org/t/psa-program-point-semantics-change/81479

Added: 
    

Modified: 
    flang/lib/Optimizer/Transforms/StackArrays.cpp
    mlir/include/mlir/Analysis/DataFlow/DeadCodeAnalysis.h
    mlir/include/mlir/Analysis/DataFlow/DenseAnalysis.h
    mlir/include/mlir/Analysis/DataFlow/SparseAnalysis.h
    mlir/include/mlir/Analysis/DataFlowFramework.h
    mlir/include/mlir/IR/Block.h
    mlir/lib/Analysis/DataFlow/DeadCodeAnalysis.cpp
    mlir/lib/Analysis/DataFlow/DenseAnalysis.cpp
    mlir/lib/Analysis/DataFlow/IntegerRangeAnalysis.cpp
    mlir/lib/Analysis/DataFlow/LivenessAnalysis.cpp
    mlir/lib/Analysis/DataFlow/SparseAnalysis.cpp
    mlir/lib/Analysis/DataFlowFramework.cpp
    mlir/lib/Dialect/Arith/Transforms/IntRangeOptimizations.cpp
    mlir/test/lib/Analysis/DataFlow/TestDeadCodeAnalysis.cpp
    mlir/test/lib/Analysis/DataFlow/TestDenseBackwardDataFlowAnalysis.cpp
    mlir/test/lib/Analysis/DataFlow/TestDenseForwardDataFlowAnalysis.cpp
    mlir/test/lib/Analysis/DataFlow/TestSparseBackwardDataFlowAnalysis.cpp
    mlir/test/lib/Analysis/TestDataFlowFramework.cpp

Removed: 
    


################################################################################
diff  --git a/flang/lib/Optimizer/Transforms/StackArrays.cpp b/flang/lib/Optimizer/Transforms/StackArrays.cpp
index d9e7bd684d4600..0c474f463f09c1 100644
--- a/flang/lib/Optimizer/Transforms/StackArrays.cpp
+++ b/flang/lib/Optimizer/Transforms/StackArrays.cpp
@@ -375,7 +375,7 @@ mlir::LogicalResult AllocationAnalysis::visitOperation(
     }
   } else if (mlir::isa<fir::ResultOp>(op)) {
     mlir::Operation *parent = op->getParentOp();
-    LatticePoint *parentLattice = getLattice(parent);
+    LatticePoint *parentLattice = getLattice(getProgramPointAfter(parent));
     assert(parentLattice);
     mlir::ChangeResult parentChanged = parentLattice->join(*after);
     propagateIfChanged(parentLattice, parentChanged);
@@ -396,28 +396,29 @@ void AllocationAnalysis::setToEntryState(LatticePoint *lattice) {
 /// Mostly a copy of AbstractDenseLattice::processOperation - the 
diff erence
 /// being that call operations are passed through to the transfer function
 mlir::LogicalResult AllocationAnalysis::processOperation(mlir::Operation *op) {
+  mlir::ProgramPoint *point = getProgramPointAfter(op);
   // If the containing block is not executable, bail out.
-  if (!getOrCreateFor<mlir::dataflow::Executable>(op, op->getBlock())->isLive())
+  if (op->getBlock() != nullptr &&
+      !getOrCreateFor<mlir::dataflow::Executable>(
+           point, getProgramPointBefore(op->getBlock()))
+           ->isLive())
     return mlir::success();
 
   // Get the dense lattice to update
-  mlir::dataflow::AbstractDenseLattice *after = getLattice(op);
+  mlir::dataflow::AbstractDenseLattice *after = getLattice(point);
 
   // If this op implements region control-flow, then control-flow dictates its
   // transfer function.
   if (auto branch = mlir::dyn_cast<mlir::RegionBranchOpInterface>(op)) {
-    visitRegionBranchOperation(op, branch, after);
+    visitRegionBranchOperation(point, branch, after);
     return mlir::success();
   }
 
   // pass call operations through to the transfer function
 
   // Get the dense state before the execution of the op.
-  const mlir::dataflow::AbstractDenseLattice *before;
-  if (mlir::Operation *prev = op->getPrevNode())
-    before = getLatticeFor(op, prev);
-  else
-    before = getLatticeFor(op, op->getBlock());
+  const mlir::dataflow::AbstractDenseLattice *before =
+      getLatticeFor(point, getProgramPointBefore(op));
 
   /// Invoke the operation transfer function
   return visitOperationImpl(op, *before, after);
@@ -452,9 +453,10 @@ StackArraysAnalysisWrapper::analyseFunction(mlir::Operation *func) {
     return mlir::failure();
   }
 
-  LatticePoint point{func};
+  LatticePoint point{solver.getProgramPointAfter(func)};
   auto joinOperationLattice = [&](mlir::Operation *op) {
-    const LatticePoint *lattice = solver.lookupState<LatticePoint>(op);
+    const LatticePoint *lattice =
+        solver.lookupState<LatticePoint>(solver.getProgramPointAfter(op));
     // there will be no lattice for an unreachable block
     if (lattice)
       (void)point.join(*lattice);

diff  --git a/mlir/include/mlir/Analysis/DataFlow/DeadCodeAnalysis.h b/mlir/include/mlir/Analysis/DataFlow/DeadCodeAnalysis.h
index 80c8b86c63678a..2250db823b5519 100644
--- a/mlir/include/mlir/Analysis/DataFlow/DeadCodeAnalysis.h
+++ b/mlir/include/mlir/Analysis/DataFlow/DeadCodeAnalysis.h
@@ -182,7 +182,7 @@ class DeadCodeAnalysis : public DataFlowAnalysis {
 
   /// Visit an operation with control-flow semantics and deduce which of its
   /// successors are live.
-  LogicalResult visit(ProgramPoint point) override;
+  LogicalResult visit(ProgramPoint *point) override;
 
 private:
   /// Find and mark symbol callables with potentially unknown callsites as

diff  --git a/mlir/include/mlir/Analysis/DataFlow/DenseAnalysis.h b/mlir/include/mlir/Analysis/DataFlow/DenseAnalysis.h
index 7917f1e3ba6485..2e32bd1bc14617 100644
--- a/mlir/include/mlir/Analysis/DataFlow/DenseAnalysis.h
+++ b/mlir/include/mlir/Analysis/DataFlow/DenseAnalysis.h
@@ -36,8 +36,7 @@ enum class CallControlFlowAction { EnterCallee, ExitCallee, ExternalCallee };
 //===----------------------------------------------------------------------===//
 
 /// This class represents a dense lattice. A dense lattice is attached to
-/// operations to represent the program state after their execution or to blocks
-/// to represent the program state at the beginning of the block. A dense
+/// program point to represent the program state at the program point.
 /// lattice is propagated through the IR by dense data-flow analysis.
 class AbstractDenseLattice : public AnalysisState {
 public:
@@ -59,15 +58,13 @@ class AbstractDenseLattice : public AnalysisState {
 //===----------------------------------------------------------------------===//
 
 /// Base class for dense forward data-flow analyses. Dense data-flow analysis
-/// attaches a lattice between the execution of operations and implements a
-/// transfer function from the lattice before each operation to the lattice
-/// after. The lattice contains information about the state of the program at
-/// that point.
+/// attaches a lattice to program points and implements a transfer function from
+/// the lattice before each operation to the lattice after. The lattice contains
+/// information about the state of the program at that program point.
 ///
-/// In this implementation, a lattice attached to an operation represents the
-/// state of the program after its execution, and a lattice attached to block
-/// represents the state of the program right before it starts executing its
-/// body.
+/// Visit a program point in forward dense data-flow analysis will invoke the
+/// transfer function of the operation preceding the program point iterator.
+/// Visit a program point at the begining of block will visit the block itself.
 class AbstractDenseForwardDataFlowAnalysis : public DataFlowAnalysis {
 public:
   using DataFlowAnalysis::DataFlowAnalysis;
@@ -76,13 +73,14 @@ class AbstractDenseForwardDataFlowAnalysis : public DataFlowAnalysis {
   /// may modify the program state; that is, every operation and block.
   LogicalResult initialize(Operation *top) override;
 
-  /// Visit a program point that modifies the state of the program. If this is a
-  /// block, then the state is propagated from control-flow predecessors or
-  /// callsites. If this is a call operation or region control-flow operation,
-  /// then the state after the execution of the operation is set by control-flow
-  /// or the callgraph. Otherwise, this function invokes the operation transfer
-  /// function.
-  LogicalResult visit(ProgramPoint point) override;
+  /// Visit a program point that modifies the state of the program. If the
+  /// program point is at the beginning of a block, then the state is propagated
+  /// from control-flow predecessors or callsites.  If the operation before
+  /// program point iterator is a call operation or region control-flow
+  /// operation, then the state after the execution of the operation is set by
+  /// control-flow or the callgraph. Otherwise, this function invokes the
+  /// operation transfer function before the program point iterator.
+  LogicalResult visit(ProgramPoint *point) override;
 
 protected:
   /// Propagate the dense lattice before the execution of an operation to the
@@ -91,15 +89,14 @@ class AbstractDenseForwardDataFlowAnalysis : public DataFlowAnalysis {
                                            const AbstractDenseLattice &before,
                                            AbstractDenseLattice *after) = 0;
 
-  /// Get the dense lattice after the execution of the given lattice anchor.
+  /// Get the dense lattice on the given lattice anchor.
   virtual AbstractDenseLattice *getLattice(LatticeAnchor anchor) = 0;
 
-  /// Get the dense lattice after the execution of the given program point and
-  /// add it as a dependency to a lattice anchor. That is, every time the
-  /// lattice after anchor is updated, the dependent program point must be
-  /// visited, and the newly triggered visit might update the lattice after
-  /// dependent.
-  const AbstractDenseLattice *getLatticeFor(ProgramPoint dependent,
+  /// Get the dense lattice on the given lattice anchor and add dependent as its
+  /// dependency. That is, every time the lattice after anchor is updated, the
+  /// dependent program point must be visited, and the newly triggered visit
+  /// might update the lattice on dependent.
+  const AbstractDenseLattice *getLatticeFor(ProgramPoint *dependent,
                                             LatticeAnchor anchor);
 
   /// Set the dense lattice at control flow entry point and propagate an update
@@ -153,7 +150,7 @@ class AbstractDenseForwardDataFlowAnalysis : public DataFlowAnalysis {
   /// Visit a program point within a region branch operation with predecessors
   /// in it. This can either be an entry block of one of the regions of the
   /// parent operation itself.
-  void visitRegionBranchOperation(ProgramPoint point,
+  void visitRegionBranchOperation(ProgramPoint *point,
                                   RegionBranchOpInterface branch,
                                   AbstractDenseLattice *after);
 
@@ -294,14 +291,12 @@ class DenseForwardDataFlowAnalysis
 //===----------------------------------------------------------------------===//
 
 /// Base class for dense backward dataflow analyses. Such analyses attach a
-/// lattice between the execution of operations and implement a transfer
-/// function from the lattice after the operation ot the lattice before it, thus
-/// propagating backward.
+/// lattice to program point and implement a transfer function from the lattice
+/// after the operation to the lattice before it, thus propagating backward.
 ///
-/// In this implementation, a lattice attached to an operation represents the
-/// state of the program before its execution, and a lattice attached to a block
-/// represents the state of the program before the end of the block, i.e., after
-/// its terminator.
+/// Visit a program point in dense backward data-flow analysis will invoke the
+/// transfer function of the operation following the program point iterator.
+/// Visit a program point at the end of block will visit the block itself.
 class AbstractDenseBackwardDataFlowAnalysis : public DataFlowAnalysis {
 public:
   /// Construct the analysis in the given solver. Takes a symbol table
@@ -321,9 +316,9 @@ class AbstractDenseBackwardDataFlowAnalysis : public DataFlowAnalysis {
   /// operations, the state is propagated using the transfer function
   /// (visitOperation).
   ///
-  /// Note: the transfer function is currently *not* invoked for operations with
-  /// region or call interface, but *is* invoked for block terminators.
-  LogicalResult visit(ProgramPoint point) override;
+  /// Note: the transfer function is currently *not* invoked before operations
+  /// with region or call interface, but *is* invoked before block terminators.
+  LogicalResult visit(ProgramPoint *point) override;
 
 protected:
   /// Propagate the dense lattice after the execution of an operation to the
@@ -337,10 +332,11 @@ class AbstractDenseBackwardDataFlowAnalysis : public DataFlowAnalysis {
   /// block.
   virtual AbstractDenseLattice *getLattice(LatticeAnchor anchor) = 0;
 
-  /// Get the dense lattice before the execution of the program point in
-  /// `anchor` and declare that the `dependent` program point must be updated
-  /// every time `point` is.
-  const AbstractDenseLattice *getLatticeFor(ProgramPoint dependent,
+  /// Get the dense lattice on the given lattice anchor and add dependent as its
+  /// dependency. That is, every time the lattice after anchor is updated, the
+  /// dependent program point must be visited, and the newly triggered visit
+  /// might update the lattice before dependent.
+  const AbstractDenseLattice *getLatticeFor(ProgramPoint *dependent,
                                             LatticeAnchor anchor);
 
   /// Set the dense lattice before at the control flow exit point and propagate
@@ -400,7 +396,7 @@ class AbstractDenseBackwardDataFlowAnalysis : public DataFlowAnalysis {
   /// (from which the state is propagated) in or after it. `regionNo` indicates
   /// the region that contains the successor, `nullopt` indicating the successor
   /// of the branch operation itself.
-  void visitRegionBranchOperation(ProgramPoint point,
+  void visitRegionBranchOperation(ProgramPoint *point,
                                   RegionBranchOpInterface branch,
                                   RegionBranchPoint branchPoint,
                                   AbstractDenseLattice *before);

diff  --git a/mlir/include/mlir/Analysis/DataFlow/SparseAnalysis.h b/mlir/include/mlir/Analysis/DataFlow/SparseAnalysis.h
index 933790b4f2a6eb..dce7ab3bb5ee79 100644
--- a/mlir/include/mlir/Analysis/DataFlow/SparseAnalysis.h
+++ b/mlir/include/mlir/Analysis/DataFlow/SparseAnalysis.h
@@ -179,18 +179,22 @@ class Lattice : public AbstractSparseLattice {
 /// operands to the lattices of the results. This analysis will propagate
 /// lattices across control-flow edges and the callgraph using liveness
 /// information.
+///
+/// Visit a program point in sparse forward data-flow analysis will invoke the
+/// transfer function of the operation preceding the program point iterator.
+/// Visit a program point at the begining of block will visit the block itself.
 class AbstractSparseForwardDataFlowAnalysis : public DataFlowAnalysis {
 public:
   /// Initialize the analysis by visiting every owner of an SSA value: all
   /// operations and blocks.
   LogicalResult initialize(Operation *top) override;
 
-  /// Visit a program point. If this is a block and all control-flow
-  /// predecessors or callsites are known, then the arguments lattices are
-  /// propagated from them. If this is a call operation or an operation with
-  /// region control-flow, then its result lattices are set accordingly.
-  /// Otherwise, the operation transfer function is invoked.
-  LogicalResult visit(ProgramPoint point) override;
+  /// Visit a program point. If this is at beginning of block and all
+  /// control-flow predecessors or callsites are known, then the arguments
+  /// lattices are propagated from them. If this is after call operation or an
+  /// operation with region control-flow, then its result lattices are set
+  /// accordingly.  Otherwise, the operation transfer function is invoked.
+  LogicalResult visit(ProgramPoint *point) override;
 
 protected:
   explicit AbstractSparseForwardDataFlowAnalysis(DataFlowSolver &solver);
@@ -221,7 +225,7 @@ class AbstractSparseForwardDataFlowAnalysis : public DataFlowAnalysis {
 
   /// Get a read-only lattice element for a value and add it as a dependency to
   /// a program point.
-  const AbstractSparseLattice *getLatticeElementFor(ProgramPoint point,
+  const AbstractSparseLattice *getLatticeElementFor(ProgramPoint *point,
                                                     Value value);
 
   /// Set the given lattice element(s) at control flow entry point(s).
@@ -251,7 +255,8 @@ class AbstractSparseForwardDataFlowAnalysis : public DataFlowAnalysis {
   /// operation `branch`, which can either be the entry block of one of the
   /// regions or the parent operation itself, and set either the argument or
   /// parent result lattices.
-  void visitRegionSuccessors(ProgramPoint point, RegionBranchOpInterface branch,
+  void visitRegionSuccessors(ProgramPoint *point,
+                             RegionBranchOpInterface branch,
                              RegionBranchPoint successor,
                              ArrayRef<AbstractSparseLattice *> lattices);
 };
@@ -312,7 +317,7 @@ class SparseForwardDataFlowAnalysis
 
   /// Get the lattice element for a value and create a dependency on the
   /// provided program point.
-  const StateT *getLatticeElementFor(ProgramPoint point, Value value) {
+  const StateT *getLatticeElementFor(ProgramPoint *point, Value value) {
     return static_cast<const StateT *>(
         AbstractSparseForwardDataFlowAnalysis::getLatticeElementFor(point,
                                                                     value));
@@ -377,10 +382,10 @@ class AbstractSparseBackwardDataFlowAnalysis : public DataFlowAnalysis {
   /// under it.
   LogicalResult initialize(Operation *top) override;
 
-  /// Visit a program point. If this is a call operation or an operation with
+  /// Visit a program point. If it is after call operation or an operation with
   /// block or region control-flow, then operand lattices are set accordingly.
   /// Otherwise, invokes the operation transfer function (`visitOperationImpl`).
-  LogicalResult visit(ProgramPoint point) override;
+  LogicalResult visit(ProgramPoint *point) override;
 
 protected:
   explicit AbstractSparseBackwardDataFlowAnalysis(
@@ -445,14 +450,14 @@ class AbstractSparseBackwardDataFlowAnalysis : public DataFlowAnalysis {
   /// Get the lattice element for a value, and also set up
   /// dependencies so that the analysis on the given ProgramPoint is re-invoked
   /// if the value changes.
-  const AbstractSparseLattice *getLatticeElementFor(ProgramPoint point,
+  const AbstractSparseLattice *getLatticeElementFor(ProgramPoint *point,
                                                     Value value);
 
   /// Get the lattice elements for a range of values, and also set up
   /// dependencies so that the analysis on the given ProgramPoint is re-invoked
   /// if any of the values change.
   SmallVector<const AbstractSparseLattice *>
-  getLatticeElementsFor(ProgramPoint point, ValueRange values);
+  getLatticeElementsFor(ProgramPoint *point, ValueRange values);
 
   SymbolTableCollection &symbolTable;
 };
@@ -465,6 +470,10 @@ class AbstractSparseBackwardDataFlowAnalysis : public DataFlowAnalysis {
 /// backwards across the IR by implementing transfer functions for operations.
 ///
 /// `StateT` is expected to be a subclass of `AbstractSparseLattice`.
+///
+/// Visit a program point in sparse backward data-flow analysis will invoke the
+/// transfer function of the operation preceding the program point iterator.
+/// Visit a program point at the begining of block will visit the block itself.
 template <typename StateT>
 class SparseBackwardDataFlowAnalysis
     : public AbstractSparseBackwardDataFlowAnalysis {

diff  --git a/mlir/include/mlir/Analysis/DataFlowFramework.h b/mlir/include/mlir/Analysis/DataFlowFramework.h
index b0450ecdbd99b8..969664dc7a4fe3 100644
--- a/mlir/include/mlir/Analysis/DataFlowFramework.h
+++ b/mlir/include/mlir/Analysis/DataFlowFramework.h
@@ -18,10 +18,12 @@
 
 #include "mlir/IR/Operation.h"
 #include "mlir/Support/StorageUniquer.h"
+#include "llvm/ADT/Hashing.h"
 #include "llvm/ADT/SetVector.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/TypeName.h"
 #include <queue>
+#include <tuple>
 
 namespace mlir {
 
@@ -51,23 +53,104 @@ class AnalysisState;
 
 /// Program point represents a specific location in the execution of a program.
 /// A sequence of program points can be combined into a control flow graph.
-struct ProgramPoint : public PointerUnion<Operation *, Block *> {
-  using ParentTy = PointerUnion<Operation *, Block *>;
-  /// Inherit constructors.
-  using ParentTy::PointerUnion;
-  /// Allow implicit conversion from the parent type.
-  ProgramPoint(ParentTy point = nullptr) : ParentTy(point) {}
-  /// Allow implicit conversions from operation wrappers.
-  /// TODO: For Windows only. Find a better solution.
-  template <typename OpT, typename = std::enable_if_t<
-                              std::is_convertible<OpT, Operation *>::value &&
-                              !std::is_same<OpT, Operation *>::value>>
-  ProgramPoint(OpT op) : ParentTy(op) {}
+struct ProgramPoint : public StorageUniquer::BaseStorage {
+  /// Creates a new program point at the given location.
+  ProgramPoint(Block *parentBlock, Block::iterator pp)
+      : block(parentBlock), point(pp) {}
+
+  /// Creates a new program point at the given operation.
+  ProgramPoint(Operation *op) : op(op) {}
+
+  /// The concrete key type used by the storage uniquer. This class is uniqued
+  /// by its contents.
+  using KeyTy = std::tuple<Block *, Block::iterator, Operation *>;
+
+  /// Create a empty program point.
+  ProgramPoint() {}
+
+  /// Create a new program point from the given program point.
+  ProgramPoint(const ProgramPoint &point) {
+    this->block = point.getBlock();
+    this->point = point.getPoint();
+    this->op = point.getOperation();
+  }
+
+  static ProgramPoint *construct(StorageUniquer::StorageAllocator &alloc,
+                                 KeyTy &&key) {
+    if (std::get<0>(key)) {
+      return new (alloc.allocate<ProgramPoint>())
+          ProgramPoint(std::get<0>(key), std::get<1>(key));
+    }
+    return new (alloc.allocate<ProgramPoint>()) ProgramPoint(std::get<2>(key));
+  }
+
+  /// Returns true if this program point is set.
+  bool isNull() const { return block == nullptr && op == nullptr; }
+
+  /// Two program points are equal if their block and iterator are equal.
+  bool operator==(const KeyTy &key) const {
+    return block == std::get<0>(key) && point == std::get<1>(key) &&
+           op == std::get<2>(key);
+  }
+
+  bool operator==(const ProgramPoint &pp) const {
+    return block == pp.block && point == pp.point && op == pp.op;
+  }
+
+  /// Get the block contains this program point.
+  Block *getBlock() const { return block; }
+
+  /// Get the the iterator this program point refers to.
+  Block::iterator getPoint() const { return point; }
+
+  /// Get the the iterator this program point refers to.
+  Operation *getOperation() const { return op; }
+
+  /// Get the next operation of this program point.
+  Operation *getNextOp() const {
+    assert(!isBlockEnd());
+    // If the current program point has no parent block, both the next op and
+    // the previous op point to the op corresponding to the current program
+    // point.
+    if (block == nullptr) {
+      return op;
+    }
+    return &*point;
+  }
+
+  /// Get the previous operation of this program point.
+  Operation *getPrevOp() const {
+    assert(!isBlockStart());
+    // If the current program point has no parent block, both the next op and
+    // the previous op point to the op corresponding to the current program
+    // point.
+    if (block == nullptr) {
+      return op;
+    }
+    return &*(--Block::iterator(point));
+  }
+
+  bool isBlockStart() const { return block && block->begin() == point; }
+
+  bool isBlockEnd() const { return block && block->end() == point; }
 
   /// Print the program point.
   void print(raw_ostream &os) const;
+
+private:
+  Block *block = nullptr;
+  Block::iterator point;
+
+  /// For operations without a parent block, we record the operation itself as
+  /// its program point.
+  Operation *op = nullptr;
 };
 
+inline raw_ostream &operator<<(raw_ostream &os, ProgramPoint point) {
+  point.print(os);
+  return os;
+}
+
 //===----------------------------------------------------------------------===//
 // GenericLatticeAnchor
 //===----------------------------------------------------------------------===//
@@ -165,21 +248,12 @@ class GenericLatticeAnchorBase : public GenericLatticeAnchor {
 
 /// Fundamental IR components are supported as first-class lattice anchor.
 struct LatticeAnchor
-    : public PointerUnion<GenericLatticeAnchor *, ProgramPoint, Value> {
-  using ParentTy = PointerUnion<GenericLatticeAnchor *, ProgramPoint, Value>;
+    : public PointerUnion<GenericLatticeAnchor *, ProgramPoint *, Value> {
+  using ParentTy = PointerUnion<GenericLatticeAnchor *, ProgramPoint *, Value>;
   /// Inherit constructors.
   using ParentTy::PointerUnion;
   /// Allow implicit conversion from the parent type.
   LatticeAnchor(ParentTy point = nullptr) : ParentTy(point) {}
-  /// Allow implicit conversions from operation wrappers.
-  /// TODO: For Windows only. Find a better solution.
-  template <typename OpT, typename = std::enable_if_t<
-                              std::is_convertible<OpT, Operation *>::value &&
-                              !std::is_same<OpT, Operation *>::value>>
-  LatticeAnchor(OpT op) : ParentTy(ProgramPoint(op)) {}
-
-  LatticeAnchor(Operation *op) : ParentTy(ProgramPoint(op)) {}
-  LatticeAnchor(Block *block) : ParentTy(ProgramPoint(block)) {}
 
   /// Print the lattice anchor.
   void print(raw_ostream &os) const;
@@ -238,7 +312,9 @@ class DataFlowConfig {
 class DataFlowSolver {
 public:
   explicit DataFlowSolver(const DataFlowConfig &config = DataFlowConfig())
-      : config(config) {}
+      : config(config) {
+    uniquer.registerParametricStorageType<ProgramPoint>();
+  }
 
   /// Load an analysis into the solver. Return the analysis instance.
   template <typename AnalysisT, typename... Args>
@@ -277,10 +353,39 @@ class DataFlowSolver {
     return AnchorT::get(uniquer, std::forward<Args>(args)...);
   }
 
+  /// Get a uniqued program point instance.
+  ProgramPoint *getProgramPointBefore(Operation *op) {
+    if (op->getBlock())
+      return uniquer.get<ProgramPoint>(/*initFn*/ {}, op->getBlock(),
+                                       Block::iterator(op), nullptr);
+    else
+      return uniquer.get<ProgramPoint>(/*initFn*/ {}, nullptr,
+                                       Block::iterator(), op);
+  }
+
+  ProgramPoint *getProgramPointBefore(Block *block) {
+    return uniquer.get<ProgramPoint>(/*initFn*/ {}, block, block->begin(),
+                                     nullptr);
+  }
+
+  ProgramPoint *getProgramPointAfter(Operation *op) {
+    if (op->getBlock())
+      return uniquer.get<ProgramPoint>(/*initFn*/ {}, op->getBlock(),
+                                       ++Block::iterator(op), nullptr);
+    else
+      return uniquer.get<ProgramPoint>(/*initFn*/ {}, nullptr,
+                                       Block::iterator(), op);
+  }
+
+  ProgramPoint *getProgramPointAfter(Block *block) {
+    return uniquer.get<ProgramPoint>(/*initFn*/ {}, block, block->end(),
+                                     nullptr);
+  }
+
   /// A work item on the solver queue is a program point, child analysis pair.
   /// Each item is processed by invoking the child analysis at the program
   /// point.
-  using WorkItem = std::pair<ProgramPoint, DataFlowAnalysis *>;
+  using WorkItem = std::pair<ProgramPoint *, DataFlowAnalysis *>;
   /// Push a work item onto the worklist.
   void enqueue(WorkItem item) { worklist.push(std::move(item)); }
 
@@ -343,7 +448,7 @@ class AnalysisState {
 public:
   virtual ~AnalysisState();
 
-  /// Create the analysis state at the given lattice anchor.
+  /// Create the analysis state on the given lattice anchor.
   AnalysisState(LatticeAnchor anchor) : anchor(anchor) {}
 
   /// Returns the lattice anchor this state is located at.
@@ -356,7 +461,7 @@ class AnalysisState {
   /// Add a dependency to this analysis state on a lattice anchor and an
   /// analysis. If this state is updated, the analysis will be invoked on the
   /// given lattice anchor again (in onUpdate()).
-  void addDependency(ProgramPoint point, DataFlowAnalysis *analysis);
+  void addDependency(ProgramPoint *point, DataFlowAnalysis *analysis);
 
 protected:
   /// This function is called by the solver when the analysis state is updated
@@ -446,12 +551,12 @@ class DataFlowAnalysis {
   /// `visit` can add new dependencies, but these dependencies will not be
   /// dynamically added to the worklist because the solver doesn't know what
   /// will provide a value for then.
-  virtual LogicalResult visit(ProgramPoint point) = 0;
+  virtual LogicalResult visit(ProgramPoint *point) = 0;
 
 protected:
   /// Create a dependency between the given analysis state and lattice anchor
   /// on this analysis.
-  void addDependency(AnalysisState *state, ProgramPoint point);
+  void addDependency(AnalysisState *state, ProgramPoint *point);
 
   /// Propagate an update to a state if it changed.
   void propagateIfChanged(AnalysisState *state, ChangeResult changed);
@@ -480,12 +585,29 @@ class DataFlowAnalysis {
   /// on `dependent`. If the return state is updated elsewhere, this analysis is
   /// re-invoked on the dependent.
   template <typename StateT, typename AnchorT>
-  const StateT *getOrCreateFor(ProgramPoint dependent, AnchorT anchor) {
+  const StateT *getOrCreateFor(ProgramPoint *dependent, AnchorT anchor) {
     StateT *state = getOrCreate<StateT>(anchor);
     addDependency(state, dependent);
     return state;
   }
 
+  /// Get a uniqued program point instance.
+  ProgramPoint *getProgramPointBefore(Operation *op) {
+    return solver.getProgramPointBefore(op);
+  }
+
+  ProgramPoint *getProgramPointBefore(Block *block) {
+    return solver.getProgramPointBefore(block);
+  }
+
+  ProgramPoint *getProgramPointAfter(Operation *op) {
+    return solver.getProgramPointAfter(op);
+  }
+
+  ProgramPoint *getProgramPointAfter(Block *block) {
+    return solver.getProgramPointAfter(block);
+  }
+
   /// Return the configuration of the solver used for this analysis.
   const DataFlowConfig &getSolverConfig() const { return solver.getConfig(); }
 
@@ -539,12 +661,30 @@ inline raw_ostream &operator<<(raw_ostream &os, LatticeAnchor anchor) {
 namespace llvm {
 /// Allow hashing of lattice anchors and program points.
 template <>
-struct DenseMapInfo<mlir::LatticeAnchor>
-    : public DenseMapInfo<mlir::LatticeAnchor::ParentTy> {};
+struct DenseMapInfo<mlir::ProgramPoint> {
+  static mlir::ProgramPoint getEmptyKey() {
+    void *pointer = llvm::DenseMapInfo<void *>::getEmptyKey();
+    return mlir::ProgramPoint(
+        (mlir::Block *)pointer,
+        mlir::Block::iterator((mlir::Operation *)pointer));
+  }
+  static mlir::ProgramPoint getTombstoneKey() {
+    void *pointer = llvm::DenseMapInfo<void *>::getTombstoneKey();
+    return mlir::ProgramPoint(
+        (mlir::Block *)pointer,
+        mlir::Block::iterator((mlir::Operation *)pointer));
+  }
+  static unsigned getHashValue(mlir::ProgramPoint pp) {
+    return hash_combine(pp.getBlock(), pp.getPoint().getNodePtr());
+  }
+  static bool isEqual(mlir::ProgramPoint lhs, mlir::ProgramPoint rhs) {
+    return lhs == rhs;
+  }
+};
 
 template <>
-struct DenseMapInfo<mlir::ProgramPoint>
-    : public DenseMapInfo<mlir::ProgramPoint::ParentTy> {};
+struct DenseMapInfo<mlir::LatticeAnchor>
+    : public DenseMapInfo<mlir::LatticeAnchor::ParentTy> {};
 
 // Allow llvm::cast style functions.
 template <typename To>
@@ -555,19 +695,6 @@ template <typename To>
 struct CastInfo<To, const mlir::LatticeAnchor>
     : public CastInfo<To, const mlir::LatticeAnchor::PointerUnion> {};
 
-template <typename To>
-struct CastInfo<To, mlir::ProgramPoint>
-    : public CastInfo<To, mlir::ProgramPoint::PointerUnion> {};
-
-template <typename To>
-struct CastInfo<To, const mlir::ProgramPoint>
-    : public CastInfo<To, const mlir::ProgramPoint::PointerUnion> {};
-
-/// Allow stealing the low bits of a ProgramPoint.
-template <>
-struct PointerLikeTypeTraits<mlir::ProgramPoint>
-    : public PointerLikeTypeTraits<mlir::ProgramPoint::ParentTy> {};
-
 } // end namespace llvm
 
 #endif // MLIR_ANALYSIS_DATAFLOWFRAMEWORK_H

diff  --git a/mlir/include/mlir/IR/Block.h b/mlir/include/mlir/IR/Block.h
index 67825eb1704bbe..536cbf9018e898 100644
--- a/mlir/include/mlir/IR/Block.h
+++ b/mlir/include/mlir/IR/Block.h
@@ -406,4 +406,25 @@ class alignas(8) Block : public IRObjectWithUseList<BlockOperand>,
 raw_ostream &operator<<(raw_ostream &, Block &);
 } // namespace mlir
 
+namespace llvm {
+template <>
+struct DenseMapInfo<mlir::Block::iterator> {
+  static mlir::Block::iterator getEmptyKey() {
+    void *pointer = llvm::DenseMapInfo<void *>::getEmptyKey();
+    return mlir::Block::iterator((mlir::Operation *)pointer);
+  }
+  static mlir::Block::iterator getTombstoneKey() {
+    void *pointer = llvm::DenseMapInfo<void *>::getTombstoneKey();
+    return mlir::Block::iterator((mlir::Operation *)pointer);
+  }
+  static unsigned getHashValue(mlir::Block::iterator iter) {
+    return hash_value(iter.getNodePtr());
+  }
+  static bool isEqual(mlir::Block::iterator lhs, mlir::Block::iterator rhs) {
+    return lhs == rhs;
+  }
+};
+
+} // end namespace llvm
+
 #endif // MLIR_IR_BLOCK_H

diff  --git a/mlir/lib/Analysis/DataFlow/DeadCodeAnalysis.cpp b/mlir/lib/Analysis/DataFlow/DeadCodeAnalysis.cpp
index beb68018a3b16e..3c190d4e991919 100644
--- a/mlir/lib/Analysis/DataFlow/DeadCodeAnalysis.cpp
+++ b/mlir/lib/Analysis/DataFlow/DeadCodeAnalysis.cpp
@@ -46,22 +46,23 @@ void Executable::print(raw_ostream &os) const {
 void Executable::onUpdate(DataFlowSolver *solver) const {
   AnalysisState::onUpdate(solver);
 
-  if (ProgramPoint pp = llvm::dyn_cast_if_present<ProgramPoint>(anchor)) {
-    if (Block *block = llvm::dyn_cast_if_present<Block *>(pp)) {
+  if (ProgramPoint *pp = llvm::dyn_cast_if_present<ProgramPoint *>(anchor)) {
+    if (pp->isBlockStart()) {
       // Re-invoke the analyses on the block itself.
       for (DataFlowAnalysis *analysis : subscribers)
-        solver->enqueue({block, analysis});
+        solver->enqueue({pp, analysis});
       // Re-invoke the analyses on all operations in the block.
       for (DataFlowAnalysis *analysis : subscribers)
-        for (Operation &op : *block)
-          solver->enqueue({&op, analysis});
+        for (Operation &op : *pp->getBlock())
+          solver->enqueue({solver->getProgramPointAfter(&op), analysis});
     }
   } else if (auto *latticeAnchor =
                  llvm::dyn_cast_if_present<GenericLatticeAnchor *>(anchor)) {
     // Re-invoke the analysis on the successor block.
     if (auto *edge = dyn_cast<CFGEdge>(latticeAnchor)) {
       for (DataFlowAnalysis *analysis : subscribers)
-        solver->enqueue({edge->getTo(), analysis});
+        solver->enqueue(
+            {solver->getProgramPointBefore(edge->getTo()), analysis});
     }
   }
 }
@@ -125,7 +126,8 @@ LogicalResult DeadCodeAnalysis::initialize(Operation *top) {
   for (Region &region : top->getRegions()) {
     if (region.empty())
       continue;
-    auto *state = getOrCreate<Executable>(&region.front());
+    auto *state =
+        getOrCreate<Executable>(getProgramPointBefore(&region.front()));
     propagateIfChanged(state, state->setToLive());
   }
 
@@ -154,7 +156,8 @@ void DeadCodeAnalysis::initializeSymbolCallables(Operation *top) {
       // Public symbol callables or those for which we can't see all uses have
       // potentially unknown callsites.
       if (symbol.isPublic() || (!allUsesVisible && symbol.isNested())) {
-        auto *state = getOrCreate<PredecessorState>(callable);
+        auto *state =
+            getOrCreate<PredecessorState>(getProgramPointAfter(callable));
         propagateIfChanged(state, state->setHasUnknownPredecessors());
       }
       foundSymbolCallable = true;
@@ -171,7 +174,8 @@ void DeadCodeAnalysis::initializeSymbolCallables(Operation *top) {
       // If we couldn't gather the symbol uses, conservatively assume that
       // we can't track information for any nested symbols.
       return top->walk([&](CallableOpInterface callable) {
-        auto *state = getOrCreate<PredecessorState>(callable);
+        auto *state =
+            getOrCreate<PredecessorState>(getProgramPointAfter(callable));
         propagateIfChanged(state, state->setHasUnknownPredecessors());
       });
     }
@@ -182,7 +186,7 @@ void DeadCodeAnalysis::initializeSymbolCallables(Operation *top) {
       // If a callable symbol has a non-call use, then we can't be guaranteed to
       // know all callsites.
       Operation *symbol = symbolTable.lookupSymbolIn(top, use.getSymbolRef());
-      auto *state = getOrCreate<PredecessorState>(symbol);
+      auto *state = getOrCreate<PredecessorState>(getProgramPointAfter(symbol));
       propagateIfChanged(state, state->setHasUnknownPredecessors());
     }
   };
@@ -193,7 +197,7 @@ void DeadCodeAnalysis::initializeSymbolCallables(Operation *top) {
 /// Returns true if the operation is a returning terminator in region
 /// control-flow or the terminator of a callable region.
 static bool isRegionOrCallableReturn(Operation *op) {
-  return !op->getNumSuccessors() &&
+  return op->getBlock() != nullptr && !op->getNumSuccessors() &&
          isa<RegionBranchOpInterface, CallableOpInterface>(op->getParentOp()) &&
          op->getBlock()->getTerminator() == op;
 }
@@ -205,9 +209,10 @@ LogicalResult DeadCodeAnalysis::initializeRecursively(Operation *op) {
     // When the liveness of the parent block changes, make sure to re-invoke the
     // analysis on the op.
     if (op->getBlock())
-      getOrCreate<Executable>(op->getBlock())->blockContentSubscribe(this);
+      getOrCreate<Executable>(getProgramPointBefore(op->getBlock()))
+          ->blockContentSubscribe(this);
     // Visit the op.
-    if (failed(visit(op)))
+    if (failed(visit(getProgramPointAfter(op))))
       return failure();
   }
   // Recurse on nested operations.
@@ -219,7 +224,7 @@ LogicalResult DeadCodeAnalysis::initializeRecursively(Operation *op) {
 }
 
 void DeadCodeAnalysis::markEdgeLive(Block *from, Block *to) {
-  auto *state = getOrCreate<Executable>(to);
+  auto *state = getOrCreate<Executable>(getProgramPointBefore(to));
   propagateIfChanged(state, state->setToLive());
   auto *edgeState =
       getOrCreate<Executable>(getLatticeAnchor<CFGEdge>(from, to));
@@ -230,18 +235,20 @@ void DeadCodeAnalysis::markEntryBlocksLive(Operation *op) {
   for (Region &region : op->getRegions()) {
     if (region.empty())
       continue;
-    auto *state = getOrCreate<Executable>(&region.front());
+    auto *state =
+        getOrCreate<Executable>(getProgramPointBefore(&region.front()));
     propagateIfChanged(state, state->setToLive());
   }
 }
 
-LogicalResult DeadCodeAnalysis::visit(ProgramPoint point) {
-  if (point.is<Block *>())
+LogicalResult DeadCodeAnalysis::visit(ProgramPoint *point) {
+  if (point->isBlockStart())
     return success();
-  auto *op = point.get<Operation *>();
+  Operation *op = point->getPrevOp();
 
   // If the parent block is not executable, there is nothing to do.
-  if (!getOrCreate<Executable>(op->getBlock())->isLive())
+  if (op->getBlock() != nullptr &&
+      !getOrCreate<Executable>(getProgramPointBefore(op->getBlock()))->isLive())
     return success();
 
   // We have a live call op. Add this as a live predecessor of the callee.
@@ -256,7 +263,8 @@ LogicalResult DeadCodeAnalysis::visit(ProgramPoint point) {
 
       // Check if this is a callable operation.
     } else if (auto callable = dyn_cast<CallableOpInterface>(op)) {
-      const auto *callsites = getOrCreateFor<PredecessorState>(op, callable);
+      const auto *callsites = getOrCreateFor<PredecessorState>(
+          getProgramPointAfter(op), getProgramPointAfter(callable));
 
       // If the callsites could not be resolved or are known to be non-empty,
       // mark the callable as executable.
@@ -316,11 +324,13 @@ void DeadCodeAnalysis::visitCallOperation(CallOpInterface call) {
   if (isa_and_nonnull<SymbolOpInterface>(callableOp) &&
       !isExternalCallable(callableOp)) {
     // Add the live callsite.
-    auto *callsites = getOrCreate<PredecessorState>(callableOp);
+    auto *callsites =
+        getOrCreate<PredecessorState>(getProgramPointAfter(callableOp));
     propagateIfChanged(callsites, callsites->join(call));
   } else {
     // Mark this call op's predecessors as overdefined.
-    auto *predecessors = getOrCreate<PredecessorState>(call);
+    auto *predecessors =
+        getOrCreate<PredecessorState>(getProgramPointAfter(call));
     propagateIfChanged(predecessors, predecessors->setHasUnknownPredecessors());
   }
 }
@@ -378,9 +388,10 @@ void DeadCodeAnalysis::visitRegionBranchOperation(
   branch.getEntrySuccessorRegions(*operands, successors);
   for (const RegionSuccessor &successor : successors) {
     // The successor can be either an entry block or the parent operation.
-    ProgramPoint point = successor.getSuccessor()
-                             ? &successor.getSuccessor()->front()
-                             : ProgramPoint(branch);
+    ProgramPoint *point =
+        successor.getSuccessor()
+            ? getProgramPointBefore(&successor.getSuccessor()->front())
+            : getProgramPointAfter(branch);
     // Mark the entry block as executable.
     auto *state = getOrCreate<Executable>(point);
     propagateIfChanged(state, state->setToLive());
@@ -409,12 +420,15 @@ void DeadCodeAnalysis::visitRegionTerminator(Operation *op,
   for (const RegionSuccessor &successor : successors) {
     PredecessorState *predecessors;
     if (Region *region = successor.getSuccessor()) {
-      auto *state = getOrCreate<Executable>(&region->front());
+      auto *state =
+          getOrCreate<Executable>(getProgramPointBefore(&region->front()));
       propagateIfChanged(state, state->setToLive());
-      predecessors = getOrCreate<PredecessorState>(&region->front());
+      predecessors = getOrCreate<PredecessorState>(
+          getProgramPointBefore(&region->front()));
     } else {
       // Add this terminator as a predecessor to the parent op.
-      predecessors = getOrCreate<PredecessorState>(branch);
+      predecessors =
+          getOrCreate<PredecessorState>(getProgramPointAfter(branch));
     }
     propagateIfChanged(predecessors,
                        predecessors->join(op, successor.getSuccessorInputs()));
@@ -424,11 +438,13 @@ void DeadCodeAnalysis::visitRegionTerminator(Operation *op,
 void DeadCodeAnalysis::visitCallableTerminator(Operation *op,
                                                CallableOpInterface callable) {
   // Add as predecessors to all callsites this return op.
-  auto *callsites = getOrCreateFor<PredecessorState>(op, callable);
+  auto *callsites = getOrCreateFor<PredecessorState>(
+      getProgramPointAfter(op), getProgramPointAfter(callable));
   bool canResolve = op->hasTrait<OpTrait::ReturnLike>();
   for (Operation *predecessor : callsites->getKnownPredecessors()) {
     assert(isa<CallOpInterface>(predecessor));
-    auto *predecessors = getOrCreate<PredecessorState>(predecessor);
+    auto *predecessors =
+        getOrCreate<PredecessorState>(getProgramPointAfter(predecessor));
     if (canResolve) {
       propagateIfChanged(predecessors, predecessors->join(op));
     } else {

diff  --git a/mlir/lib/Analysis/DataFlow/DenseAnalysis.cpp b/mlir/lib/Analysis/DataFlow/DenseAnalysis.cpp
index 300c6e5f9b8919..340aa399ec12e5 100644
--- a/mlir/lib/Analysis/DataFlow/DenseAnalysis.cpp
+++ b/mlir/lib/Analysis/DataFlow/DenseAnalysis.cpp
@@ -44,10 +44,10 @@ LogicalResult AbstractDenseForwardDataFlowAnalysis::initialize(Operation *top) {
   return success();
 }
 
-LogicalResult AbstractDenseForwardDataFlowAnalysis::visit(ProgramPoint point) {
-  if (auto *op = llvm::dyn_cast_if_present<Operation *>(point))
-    return processOperation(op);
-  visitBlock(point.get<Block *>());
+LogicalResult AbstractDenseForwardDataFlowAnalysis::visit(ProgramPoint *point) {
+  if (!point->isBlockStart())
+    return processOperation(point->getPrevOp());
+  visitBlock(point->getBlock());
   return success();
 }
 
@@ -64,8 +64,8 @@ void AbstractDenseForwardDataFlowAnalysis::visitCallOperation(
         call, CallControlFlowAction::ExternalCallee, before, after);
   }
 
-  const auto *predecessors =
-      getOrCreateFor<PredecessorState>(call.getOperation(), call);
+  const auto *predecessors = getOrCreateFor<PredecessorState>(
+      getProgramPointAfter(call.getOperation()), getProgramPointAfter(call));
   // Otherwise, if not all return sites are known, then conservatively assume we
   // can't reason about the data-flow.
   if (!predecessors->allPredecessorsKnown())
@@ -87,7 +87,8 @@ void AbstractDenseForwardDataFlowAnalysis::visitCallOperation(
     //   }
     AbstractDenseLattice *latticeAfterCall = after;
     const AbstractDenseLattice *latticeAtCalleeReturn =
-        getLatticeFor(call.getOperation(), predecessor);
+        getLatticeFor(getProgramPointAfter(call.getOperation()),
+                      getProgramPointAfter(predecessor));
     visitCallControlFlowTransfer(call, CallControlFlowAction::ExitCallee,
                                  *latticeAtCalleeReturn, latticeAfterCall);
   }
@@ -95,24 +96,24 @@ void AbstractDenseForwardDataFlowAnalysis::visitCallOperation(
 
 LogicalResult
 AbstractDenseForwardDataFlowAnalysis::processOperation(Operation *op) {
+  ProgramPoint *point = getProgramPointAfter(op);
   // If the containing block is not executable, bail out.
-  if (!getOrCreateFor<Executable>(op, op->getBlock())->isLive())
+  if (op->getBlock() != nullptr &&
+      !getOrCreateFor<Executable>(point, getProgramPointBefore(op->getBlock()))
+           ->isLive())
     return success();
 
   // Get the dense lattice to update.
-  AbstractDenseLattice *after = getLattice(op);
+  AbstractDenseLattice *after = getLattice(point);
 
   // Get the dense state before the execution of the op.
-  const AbstractDenseLattice *before;
-  if (Operation *prev = op->getPrevNode())
-    before = getLatticeFor(op, prev);
-  else
-    before = getLatticeFor(op, op->getBlock());
+  const AbstractDenseLattice *before =
+      getLatticeFor(point, getProgramPointBefore(op));
 
   // If this op implements region control-flow, then control-flow dictates its
   // transfer function.
   if (auto branch = dyn_cast<RegionBranchOpInterface>(op)) {
-    visitRegionBranchOperation(op, branch, after);
+    visitRegionBranchOperation(point, branch, after);
     return success();
   }
 
@@ -129,11 +130,12 @@ AbstractDenseForwardDataFlowAnalysis::processOperation(Operation *op) {
 
 void AbstractDenseForwardDataFlowAnalysis::visitBlock(Block *block) {
   // If the block is not executable, bail out.
-  if (!getOrCreateFor<Executable>(block, block)->isLive())
+  ProgramPoint *point = getProgramPointBefore(block);
+  if (!getOrCreateFor<Executable>(point, point)->isLive())
     return;
 
   // Get the dense lattice to update.
-  AbstractDenseLattice *after = getLattice(block);
+  AbstractDenseLattice *after = getLattice(point);
 
   // The dense lattices of entry blocks are set by region control-flow or the
   // callgraph.
@@ -141,7 +143,8 @@ void AbstractDenseForwardDataFlowAnalysis::visitBlock(Block *block) {
     // Check if this block is the entry block of a callable region.
     auto callable = dyn_cast<CallableOpInterface>(block->getParentOp());
     if (callable && callable.getCallableRegion() == block->getParent()) {
-      const auto *callsites = getOrCreateFor<PredecessorState>(block, callable);
+      const auto *callsites = getOrCreateFor<PredecessorState>(
+          point, getProgramPointAfter(callable));
       // If not all callsites are known, conservatively mark all lattices as
       // having reached their pessimistic fixpoints. Do the same if
       // interprocedural analysis is not enabled.
@@ -151,10 +154,7 @@ void AbstractDenseForwardDataFlowAnalysis::visitBlock(Block *block) {
       for (Operation *callsite : callsites->getKnownPredecessors()) {
         // Get the dense lattice before the callsite.
         const AbstractDenseLattice *before;
-        if (Operation *prev = callsite->getPrevNode())
-          before = getLatticeFor(block, prev);
-        else
-          before = getLatticeFor(block, callsite->getBlock());
+        before = getLatticeFor(point, getProgramPointBefore(callsite));
 
         visitCallControlFlowTransfer(cast<CallOpInterface>(callsite),
                                      CallControlFlowAction::EnterCallee,
@@ -165,7 +165,7 @@ void AbstractDenseForwardDataFlowAnalysis::visitBlock(Block *block) {
 
     // Check if we can reason about the control-flow.
     if (auto branch = dyn_cast<RegionBranchOpInterface>(block->getParentOp()))
-      return visitRegionBranchOperation(block, branch, after);
+      return visitRegionBranchOperation(point, branch, after);
 
     // Otherwise, we can't reason about the data-flow.
     return setToEntryState(after);
@@ -177,17 +177,18 @@ void AbstractDenseForwardDataFlowAnalysis::visitBlock(Block *block) {
     // Skip control edges that aren't executable.
     Block *predecessor = *it;
     if (!getOrCreateFor<Executable>(
-             block, getLatticeAnchor<CFGEdge>(predecessor, block))
+             point, getLatticeAnchor<CFGEdge>(predecessor, block))
              ->isLive())
       continue;
 
     // Merge in the state from the predecessor's terminator.
-    join(after, *getLatticeFor(block, predecessor->getTerminator()));
+    join(after, *getLatticeFor(
+                    point, getProgramPointAfter(predecessor->getTerminator())));
   }
 }
 
 void AbstractDenseForwardDataFlowAnalysis::visitRegionBranchOperation(
-    ProgramPoint point, RegionBranchOpInterface branch,
+    ProgramPoint *point, RegionBranchOpInterface branch,
     AbstractDenseLattice *after) {
   // Get the terminator predecessors.
   const auto *predecessors = getOrCreateFor<PredecessorState>(point, point);
@@ -198,19 +199,15 @@ void AbstractDenseForwardDataFlowAnalysis::visitRegionBranchOperation(
     const AbstractDenseLattice *before;
     // If the predecessor is the parent, get the state before the parent.
     if (op == branch) {
-      if (Operation *prev = op->getPrevNode())
-        before = getLatticeFor(point, prev);
-      else
-        before = getLatticeFor(point, op->getBlock());
-
+      before = getLatticeFor(point, getProgramPointBefore(op));
       // Otherwise, get the state after the terminator.
     } else {
-      before = getLatticeFor(point, op);
+      before = getLatticeFor(point, getProgramPointAfter(op));
     }
 
     // This function is called in two cases:
-    //   1. when visiting the block (point = block);
-    //   2. when visiting the parent operation (point = parent op).
+    //   1. when visiting the block (point = block start);
+    //   2. when visiting the parent operation (point = iter after parent op).
     // In both cases, we are looking for predecessor operations of the point,
     //   1. predecessor may be the terminator of another block from another
     //   region (assuming that the block does belong to another region via an
@@ -224,12 +221,12 @@ void AbstractDenseForwardDataFlowAnalysis::visitRegionBranchOperation(
     std::optional<unsigned> regionFrom =
         op == branch ? std::optional<unsigned>()
                      : op->getBlock()->getParent()->getRegionNumber();
-    if (auto *toBlock = point.dyn_cast<Block *>()) {
-      unsigned regionTo = toBlock->getParent()->getRegionNumber();
+    if (point->isBlockStart()) {
+      unsigned regionTo = point->getBlock()->getParent()->getRegionNumber();
       visitRegionBranchControlFlowTransfer(branch, regionFrom, regionTo,
                                            *before, after);
     } else {
-      assert(point.get<Operation *>() == branch &&
+      assert(point->getPrevOp() == branch &&
              "expected to be visiting the branch itself");
       // Only need to call the arc transfer when the predecessor is the region
       // or the op itself, not the previous op.
@@ -244,7 +241,7 @@ void AbstractDenseForwardDataFlowAnalysis::visitRegionBranchOperation(
 }
 
 const AbstractDenseLattice *
-AbstractDenseForwardDataFlowAnalysis::getLatticeFor(ProgramPoint dependent,
+AbstractDenseForwardDataFlowAnalysis::getLatticeFor(ProgramPoint *dependent,
                                                     LatticeAnchor anchor) {
   AbstractDenseLattice *state = getLattice(anchor);
   addDependency(state, dependent);
@@ -273,10 +270,11 @@ AbstractDenseBackwardDataFlowAnalysis::initialize(Operation *top) {
   return success();
 }
 
-LogicalResult AbstractDenseBackwardDataFlowAnalysis::visit(ProgramPoint point) {
-  if (auto *op = llvm::dyn_cast_if_present<Operation *>(point))
-    return processOperation(op);
-  visitBlock(point.get<Block *>());
+LogicalResult
+AbstractDenseBackwardDataFlowAnalysis::visit(ProgramPoint *point) {
+  if (!point->isBlockEnd())
+    return processOperation(point->getNextOp());
+  visitBlock(point->getBlock());
   return success();
 }
 
@@ -316,11 +314,9 @@ void AbstractDenseBackwardDataFlowAnalysis::visitCallOperation(
   //     ...
   //   }
   Block *calleeEntryBlock = &region->front();
-  ProgramPoint calleeEntry = calleeEntryBlock->empty()
-                                 ? ProgramPoint(calleeEntryBlock)
-                                 : &calleeEntryBlock->front();
+  ProgramPoint *calleeEntry = getProgramPointBefore(calleeEntryBlock);
   const AbstractDenseLattice &latticeAtCalleeEntry =
-      *getLatticeFor(call.getOperation(), calleeEntry);
+      *getLatticeFor(getProgramPointBefore(call.getOperation()), calleeEntry);
   AbstractDenseLattice *latticeBeforeCall = before;
   visitCallControlFlowTransfer(call, CallControlFlowAction::EnterCallee,
                                latticeAtCalleeEntry, latticeBeforeCall);
@@ -328,23 +324,24 @@ void AbstractDenseBackwardDataFlowAnalysis::visitCallOperation(
 
 LogicalResult
 AbstractDenseBackwardDataFlowAnalysis::processOperation(Operation *op) {
+  ProgramPoint *point = getProgramPointBefore(op);
   // If the containing block is not executable, bail out.
-  if (!getOrCreateFor<Executable>(op, op->getBlock())->isLive())
+  if (op->getBlock() != nullptr &&
+      !getOrCreateFor<Executable>(point, getProgramPointBefore(op->getBlock()))
+           ->isLive())
     return success();
 
   // Get the dense lattice to update.
-  AbstractDenseLattice *before = getLattice(op);
+  AbstractDenseLattice *before = getLattice(point);
 
   // Get the dense state after execution of this op.
-  const AbstractDenseLattice *after;
-  if (Operation *next = op->getNextNode())
-    after = getLatticeFor(op, next);
-  else
-    after = getLatticeFor(op, op->getBlock());
+  const AbstractDenseLattice *after =
+      getLatticeFor(point, getProgramPointAfter(op));
 
   // Special cases where control flow may dictate data flow.
   if (auto branch = dyn_cast<RegionBranchOpInterface>(op)) {
-    visitRegionBranchOperation(op, branch, RegionBranchPoint::parent(), before);
+    visitRegionBranchOperation(point, branch, RegionBranchPoint::parent(),
+                               before);
     return success();
   }
   if (auto call = dyn_cast<CallOpInterface>(op)) {
@@ -357,11 +354,13 @@ AbstractDenseBackwardDataFlowAnalysis::processOperation(Operation *op) {
 }
 
 void AbstractDenseBackwardDataFlowAnalysis::visitBlock(Block *block) {
+  ProgramPoint *point = getProgramPointAfter(block);
   // If the block is not executable, bail out.
-  if (!getOrCreateFor<Executable>(block, block)->isLive())
+  if (!getOrCreateFor<Executable>(point, getProgramPointBefore(block))
+           ->isLive())
     return;
 
-  AbstractDenseLattice *before = getLattice(block);
+  AbstractDenseLattice *before = getLattice(point);
 
   // We need "exit" blocks, i.e. the blocks that may return control to the
   // parent operation.
@@ -382,7 +381,8 @@ void AbstractDenseBackwardDataFlowAnalysis::visitBlock(Block *block) {
     // themselves are predecessors of the callable.
     auto callable = dyn_cast<CallableOpInterface>(block->getParentOp());
     if (callable && callable.getCallableRegion() == block->getParent()) {
-      const auto *callsites = getOrCreateFor<PredecessorState>(block, callable);
+      const auto *callsites = getOrCreateFor<PredecessorState>(
+          point, getProgramPointAfter(callable));
       // If not all call sites are known, conservative mark all lattices as
       // having reached their pessimistic fix points.
       if (!callsites->allPredecessorsKnown() ||
@@ -391,11 +391,8 @@ void AbstractDenseBackwardDataFlowAnalysis::visitBlock(Block *block) {
       }
 
       for (Operation *callsite : callsites->getKnownPredecessors()) {
-        const AbstractDenseLattice *after;
-        if (Operation *next = callsite->getNextNode())
-          after = getLatticeFor(block, next);
-        else
-          after = getLatticeFor(block, callsite->getBlock());
+        const AbstractDenseLattice *after =
+            getLatticeFor(point, getProgramPointAfter(callsite));
         visitCallControlFlowTransfer(cast<CallOpInterface>(callsite),
                                      CallControlFlowAction::ExitCallee, *after,
                                      before);
@@ -406,7 +403,7 @@ void AbstractDenseBackwardDataFlowAnalysis::visitBlock(Block *block) {
     // If this block is exiting from an operation with region-based control
     // flow, propagate the lattice back along the control flow edge.
     if (auto branch = dyn_cast<RegionBranchOpInterface>(block->getParentOp())) {
-      visitRegionBranchOperation(block, branch, block->getParent(), before);
+      visitRegionBranchOperation(point, branch, block->getParent(), before);
       return;
     }
 
@@ -417,22 +414,19 @@ void AbstractDenseBackwardDataFlowAnalysis::visitBlock(Block *block) {
 
   // Meet the state with the state before block's successors.
   for (Block *successor : block->getSuccessors()) {
-    if (!getOrCreateFor<Executable>(block,
+    if (!getOrCreateFor<Executable>(point,
                                     getLatticeAnchor<CFGEdge>(block, successor))
              ->isLive())
       continue;
 
     // Merge in the state from the successor: either the first operation, or the
     // block itself when empty.
-    if (successor->empty())
-      meet(before, *getLatticeFor(block, successor));
-    else
-      meet(before, *getLatticeFor(block, &successor->front()));
+    meet(before, *getLatticeFor(point, getProgramPointBefore(successor)));
   }
 }
 
 void AbstractDenseBackwardDataFlowAnalysis::visitRegionBranchOperation(
-    ProgramPoint point, RegionBranchOpInterface branch,
+    ProgramPoint *point, RegionBranchOpInterface branch,
     RegionBranchPoint branchPoint, AbstractDenseLattice *before) {
 
   // The successors of the operation may be either the first operation of the
@@ -443,22 +437,18 @@ void AbstractDenseBackwardDataFlowAnalysis::visitRegionBranchOperation(
   for (const RegionSuccessor &successor : successors) {
     const AbstractDenseLattice *after;
     if (successor.isParent() || successor.getSuccessor()->empty()) {
-      if (Operation *next = branch->getNextNode())
-        after = getLatticeFor(point, next);
-      else
-        after = getLatticeFor(point, branch->getBlock());
+      after = getLatticeFor(point, getProgramPointAfter(branch));
     } else {
       Region *successorRegion = successor.getSuccessor();
       assert(!successorRegion->empty() && "unexpected empty successor region");
       Block *successorBlock = &successorRegion->front();
 
-      if (!getOrCreateFor<Executable>(point, successorBlock)->isLive())
+      if (!getOrCreateFor<Executable>(point,
+                                      getProgramPointBefore(successorBlock))
+               ->isLive())
         continue;
 
-      if (successorBlock->empty())
-        after = getLatticeFor(point, successorBlock);
-      else
-        after = getLatticeFor(point, &successorBlock->front());
+      after = getLatticeFor(point, getProgramPointBefore(successorBlock));
     }
 
     visitRegionBranchControlFlowTransfer(branch, branchPoint, successor, *after,
@@ -467,7 +457,7 @@ void AbstractDenseBackwardDataFlowAnalysis::visitRegionBranchOperation(
 }
 
 const AbstractDenseLattice *
-AbstractDenseBackwardDataFlowAnalysis::getLatticeFor(ProgramPoint dependent,
+AbstractDenseBackwardDataFlowAnalysis::getLatticeFor(ProgramPoint *dependent,
                                                      LatticeAnchor anchor) {
   AbstractDenseLattice *state = getLattice(anchor);
   addDependency(state, dependent);

diff  --git a/mlir/lib/Analysis/DataFlow/IntegerRangeAnalysis.cpp b/mlir/lib/Analysis/DataFlow/IntegerRangeAnalysis.cpp
index 9a95f172d5df48..bf9eabbedc3a1f 100644
--- a/mlir/lib/Analysis/DataFlow/IntegerRangeAnalysis.cpp
+++ b/mlir/lib/Analysis/DataFlow/IntegerRangeAnalysis.cpp
@@ -111,7 +111,7 @@ void IntegerRangeAnalysis::visitNonControlFlowArguments(
     LLVM_DEBUG(llvm::dbgs() << "Inferring ranges for " << *op << "\n");
 
     auto argRanges = llvm::map_to_vector(op->getOperands(), [&](Value value) {
-      return getLatticeElementFor(op, value)->getValue();
+      return getLatticeElementFor(getProgramPointAfter(op), value)->getValue();
     });
 
     auto joinCallback = [&](Value v, const IntegerValueRange &attrs) {
@@ -159,7 +159,7 @@ void IntegerRangeAnalysis::visitNonControlFlowArguments(
           return bound.getValue();
       } else if (auto value = llvm::dyn_cast_if_present<Value>(*loopBound)) {
         const IntegerValueRangeLattice *lattice =
-            getLatticeElementFor(op, value);
+            getLatticeElementFor(getProgramPointAfter(op), value);
         if (lattice != nullptr && !lattice->getValue().isUninitialized())
           return getUpper ? lattice->getValue().getValue().smax()
                           : lattice->getValue().getValue().smin();

diff  --git a/mlir/lib/Analysis/DataFlow/LivenessAnalysis.cpp b/mlir/lib/Analysis/DataFlow/LivenessAnalysis.cpp
index 57a4d4a6800be0..9fb4d9df2530df 100644
--- a/mlir/lib/Analysis/DataFlow/LivenessAnalysis.cpp
+++ b/mlir/lib/Analysis/DataFlow/LivenessAnalysis.cpp
@@ -87,7 +87,7 @@ LivenessAnalysis::visitOperation(Operation *op, ArrayRef<Liveness *> operands,
         meet(operand, *r);
       foundLiveResult = true;
     }
-    addDependency(const_cast<Liveness *>(r), op);
+    addDependency(const_cast<Liveness *>(r), getProgramPointAfter(op));
   }
   return success();
 }

diff  --git a/mlir/lib/Analysis/DataFlow/SparseAnalysis.cpp b/mlir/lib/Analysis/DataFlow/SparseAnalysis.cpp
index 1bd6defef90be0..67cf8c9c5b81f2 100644
--- a/mlir/lib/Analysis/DataFlow/SparseAnalysis.cpp
+++ b/mlir/lib/Analysis/DataFlow/SparseAnalysis.cpp
@@ -36,7 +36,7 @@ void AbstractSparseLattice::onUpdate(DataFlowSolver *solver) const {
   // Push all users of the value to the queue.
   for (Operation *user : anchor.get<Value>().getUsers())
     for (DataFlowAnalysis *analysis : useDefSubscribers)
-      solver->enqueue({user, analysis});
+      solver->enqueue({solver->getProgramPointAfter(user), analysis});
 }
 
 //===----------------------------------------------------------------------===//
@@ -72,7 +72,8 @@ AbstractSparseForwardDataFlowAnalysis::initializeRecursively(Operation *op) {
 
   for (Region &region : op->getRegions()) {
     for (Block &block : region) {
-      getOrCreate<Executable>(&block)->blockContentSubscribe(this);
+      getOrCreate<Executable>(getProgramPointBefore(&block))
+          ->blockContentSubscribe(this);
       visitBlock(&block);
       for (Operation &op : block)
         if (failed(initializeRecursively(&op)))
@@ -83,10 +84,11 @@ AbstractSparseForwardDataFlowAnalysis::initializeRecursively(Operation *op) {
   return success();
 }
 
-LogicalResult AbstractSparseForwardDataFlowAnalysis::visit(ProgramPoint point) {
-  if (Operation *op = llvm::dyn_cast_if_present<Operation *>(point))
-    return visitOperation(op);
-  visitBlock(point.get<Block *>());
+LogicalResult
+AbstractSparseForwardDataFlowAnalysis::visit(ProgramPoint *point) {
+  if (!point->isBlockStart())
+    return visitOperation(point->getPrevOp());
+  visitBlock(point->getBlock());
   return success();
 }
 
@@ -97,7 +99,8 @@ AbstractSparseForwardDataFlowAnalysis::visitOperation(Operation *op) {
     return success();
 
   // If the containing block is not executable, bail out.
-  if (!getOrCreate<Executable>(op->getBlock())->isLive())
+  if (op->getBlock() != nullptr &&
+      !getOrCreate<Executable>(getProgramPointBefore(op->getBlock()))->isLive())
     return success();
 
   // Get the result lattices.
@@ -110,7 +113,7 @@ AbstractSparseForwardDataFlowAnalysis::visitOperation(Operation *op) {
 
   // The results of a region branch operation are determined by control-flow.
   if (auto branch = dyn_cast<RegionBranchOpInterface>(op)) {
-    visitRegionSuccessors({branch}, branch,
+    visitRegionSuccessors(getProgramPointAfter(branch), branch,
                           /*successor=*/RegionBranchPoint::parent(),
                           resultLattices);
     return success();
@@ -138,7 +141,8 @@ AbstractSparseForwardDataFlowAnalysis::visitOperation(Operation *op) {
 
     // Otherwise, the results of a call operation are determined by the
     // callgraph.
-    const auto *predecessors = getOrCreateFor<PredecessorState>(op, call);
+    const auto *predecessors = getOrCreateFor<PredecessorState>(
+        getProgramPointAfter(op), getProgramPointAfter(call));
     // If not all return sites are known, then conservatively assume we can't
     // reason about the data-flow.
     if (!predecessors->allPredecessorsKnown()) {
@@ -148,7 +152,8 @@ AbstractSparseForwardDataFlowAnalysis::visitOperation(Operation *op) {
     for (Operation *predecessor : predecessors->getKnownPredecessors())
       for (auto &&[operand, resLattice] :
            llvm::zip(predecessor->getOperands(), resultLattices))
-        join(resLattice, *getLatticeElementFor(op, operand));
+        join(resLattice,
+             *getLatticeElementFor(getProgramPointAfter(op), operand));
     return success();
   }
 
@@ -162,7 +167,7 @@ void AbstractSparseForwardDataFlowAnalysis::visitBlock(Block *block) {
     return;
 
   // If the block is not executable, bail out.
-  if (!getOrCreate<Executable>(block)->isLive())
+  if (!getOrCreate<Executable>(getProgramPointBefore(block))->isLive())
     return;
 
   // Get the argument lattices.
@@ -179,7 +184,8 @@ void AbstractSparseForwardDataFlowAnalysis::visitBlock(Block *block) {
     // Check if this block is the entry block of a callable region.
     auto callable = dyn_cast<CallableOpInterface>(block->getParentOp());
     if (callable && callable.getCallableRegion() == block->getParent()) {
-      const auto *callsites = getOrCreateFor<PredecessorState>(block, callable);
+      const auto *callsites = getOrCreateFor<PredecessorState>(
+          getProgramPointBefore(block), getProgramPointAfter(callable));
       // If not all callsites are known, conservatively mark all lattices as
       // having reached their pessimistic fixpoints.
       if (!callsites->allPredecessorsKnown() ||
@@ -189,15 +195,17 @@ void AbstractSparseForwardDataFlowAnalysis::visitBlock(Block *block) {
       for (Operation *callsite : callsites->getKnownPredecessors()) {
         auto call = cast<CallOpInterface>(callsite);
         for (auto it : llvm::zip(call.getArgOperands(), argLattices))
-          join(std::get<1>(it), *getLatticeElementFor(block, std::get<0>(it)));
+          join(std::get<1>(it),
+               *getLatticeElementFor(getProgramPointBefore(block),
+                                     std::get<0>(it)));
       }
       return;
     }
 
     // Check if the lattices can be determined from region control flow.
     if (auto branch = dyn_cast<RegionBranchOpInterface>(block->getParentOp())) {
-      return visitRegionSuccessors(block, branch, block->getParent(),
-                                   argLattices);
+      return visitRegionSuccessors(getProgramPointBefore(block), branch,
+                                   block->getParent(), argLattices);
     }
 
     // Otherwise, we can't reason about the data-flow.
@@ -226,7 +234,8 @@ void AbstractSparseForwardDataFlowAnalysis::visitBlock(Block *block) {
           branch.getSuccessorOperands(it.getSuccessorIndex());
       for (auto [idx, lattice] : llvm::enumerate(argLattices)) {
         if (Value operand = operands[idx]) {
-          join(lattice, *getLatticeElementFor(block, operand));
+          join(lattice,
+               *getLatticeElementFor(getProgramPointBefore(block), operand));
         } else {
           // Conservatively consider internally produced arguments as entry
           // points.
@@ -240,7 +249,7 @@ void AbstractSparseForwardDataFlowAnalysis::visitBlock(Block *block) {
 }
 
 void AbstractSparseForwardDataFlowAnalysis::visitRegionSuccessors(
-    ProgramPoint point, RegionBranchOpInterface branch,
+    ProgramPoint *point, RegionBranchOpInterface branch,
     RegionBranchPoint successor, ArrayRef<AbstractSparseLattice *> lattices) {
   const auto *predecessors = getOrCreateFor<PredecessorState>(point, point);
   assert(predecessors->allPredecessorsKnown() &&
@@ -270,7 +279,7 @@ void AbstractSparseForwardDataFlowAnalysis::visitRegionSuccessors(
 
     unsigned firstIndex = 0;
     if (inputs.size() != lattices.size()) {
-      if (llvm::dyn_cast_if_present<Operation *>(point)) {
+      if (!point->isBlockStart()) {
         if (!inputs.empty())
           firstIndex = cast<OpResult>(inputs.front()).getResultNumber();
         visitNonControlFlowArgumentsImpl(
@@ -281,7 +290,7 @@ void AbstractSparseForwardDataFlowAnalysis::visitRegionSuccessors(
       } else {
         if (!inputs.empty())
           firstIndex = cast<BlockArgument>(inputs.front()).getArgNumber();
-        Region *region = point.get<Block *>()->getParent();
+        Region *region = point->getBlock()->getParent();
         visitNonControlFlowArgumentsImpl(
             branch,
             RegionSuccessor(region, region->getArguments().slice(
@@ -296,7 +305,7 @@ void AbstractSparseForwardDataFlowAnalysis::visitRegionSuccessors(
 }
 
 const AbstractSparseLattice *
-AbstractSparseForwardDataFlowAnalysis::getLatticeElementFor(ProgramPoint point,
+AbstractSparseForwardDataFlowAnalysis::getLatticeElementFor(ProgramPoint *point,
                                                             Value value) {
   AbstractSparseLattice *state = getLatticeElement(value);
   addDependency(state, point);
@@ -336,7 +345,8 @@ AbstractSparseBackwardDataFlowAnalysis::initializeRecursively(Operation *op) {
 
   for (Region &region : op->getRegions()) {
     for (Block &block : region) {
-      getOrCreate<Executable>(&block)->blockContentSubscribe(this);
+      getOrCreate<Executable>(getProgramPointBefore(&block))
+          ->blockContentSubscribe(this);
       // Initialize ops in reverse order, so we can do as much initial
       // propagation as possible without having to go through the
       // solver queue.
@@ -349,14 +359,14 @@ AbstractSparseBackwardDataFlowAnalysis::initializeRecursively(Operation *op) {
 }
 
 LogicalResult
-AbstractSparseBackwardDataFlowAnalysis::visit(ProgramPoint point) {
-  if (Operation *op = llvm::dyn_cast_if_present<Operation *>(point))
-    return visitOperation(op);
+AbstractSparseBackwardDataFlowAnalysis::visit(ProgramPoint *point) {
   // For backward dataflow, we don't have to do any work for the blocks
   // themselves. CFG edges between blocks are processed by the BranchOp
   // logic in `visitOperation`, and entry blocks for functions are tied
   // to the CallOp arguments by visitOperation.
-  return success();
+  if (point->isBlockStart())
+    return success();
+  return visitOperation(point->getPrevOp());
 }
 
 SmallVector<AbstractSparseLattice *>
@@ -372,7 +382,7 @@ AbstractSparseBackwardDataFlowAnalysis::getLatticeElements(ValueRange values) {
 
 SmallVector<const AbstractSparseLattice *>
 AbstractSparseBackwardDataFlowAnalysis::getLatticeElementsFor(
-    ProgramPoint point, ValueRange values) {
+    ProgramPoint *point, ValueRange values) {
   SmallVector<const AbstractSparseLattice *> resultLattices;
   resultLattices.reserve(values.size());
   for (Value result : values) {
@@ -390,13 +400,14 @@ static MutableArrayRef<OpOperand> operandsToOpOperands(OperandRange &operands) {
 LogicalResult
 AbstractSparseBackwardDataFlowAnalysis::visitOperation(Operation *op) {
   // If we're in a dead block, bail out.
-  if (!getOrCreate<Executable>(op->getBlock())->isLive())
+  if (op->getBlock() != nullptr &&
+      !getOrCreate<Executable>(getProgramPointBefore(op->getBlock()))->isLive())
     return success();
 
   SmallVector<AbstractSparseLattice *> operandLattices =
       getLatticeElements(op->getOperands());
   SmallVector<const AbstractSparseLattice *> resultLattices =
-      getLatticeElementsFor(op, op->getResults());
+      getLatticeElementsFor(getProgramPointAfter(op), op->getResults());
 
   // Block arguments of region branch operations flow back into the operands
   // of the parent op
@@ -425,7 +436,7 @@ AbstractSparseBackwardDataFlowAnalysis::visitOperation(Operation *op) {
                   detail::getBranchSuccessorArgument(
                       successorOperands, operand.getOperandNumber(), block)) {
             meet(getLatticeElement(operand.get()),
-                 *getLatticeElementFor(op, *blockArg));
+                 *getLatticeElementFor(getProgramPointAfter(op), *blockArg));
           }
         }
       }
@@ -467,7 +478,7 @@ AbstractSparseBackwardDataFlowAnalysis::visitOperation(Operation *op) {
       for (auto [blockArg, argOpOperand] :
            llvm::zip(block.getArguments(), argOpOperands)) {
         meet(getLatticeElement(argOpOperand.get()),
-             *getLatticeElementFor(op, blockArg));
+             *getLatticeElementFor(getProgramPointAfter(op), blockArg));
         unaccounted.reset(argOpOperand.getOperandNumber());
       }
 
@@ -502,12 +513,13 @@ AbstractSparseBackwardDataFlowAnalysis::visitOperation(Operation *op) {
     // Going backwards, the operands of the return are derived from the
     // results of all CallOps calling this CallableOp.
     if (auto callable = dyn_cast<CallableOpInterface>(op->getParentOp())) {
-      const PredecessorState *callsites =
-          getOrCreateFor<PredecessorState>(op, callable);
+      const PredecessorState *callsites = getOrCreateFor<PredecessorState>(
+          getProgramPointAfter(op), getProgramPointAfter(callable));
       if (callsites->allPredecessorsKnown()) {
         for (Operation *call : callsites->getKnownPredecessors()) {
           SmallVector<const AbstractSparseLattice *> callResultLattices =
-              getLatticeElementsFor(op, call->getResults());
+              getLatticeElementsFor(getProgramPointAfter(op),
+                                    call->getResults());
           for (auto [op, result] :
                llvm::zip(operandLattices, callResultLattices))
             meet(op, *result);
@@ -542,7 +554,8 @@ void AbstractSparseBackwardDataFlowAnalysis::visitRegionSuccessors(
     MutableArrayRef<OpOperand> opoperands = operandsToOpOperands(operands);
     ValueRange inputs = successor.getSuccessorInputs();
     for (auto [operand, input] : llvm::zip(opoperands, inputs)) {
-      meet(getLatticeElement(operand.get()), *getLatticeElementFor(op, input));
+      meet(getLatticeElement(operand.get()),
+           *getLatticeElementFor(getProgramPointAfter(op), input));
       unaccounted.reset(operand.getOperandNumber());
     }
   }
@@ -576,7 +589,7 @@ void AbstractSparseBackwardDataFlowAnalysis::
     MutableArrayRef<OpOperand> opOperands = operandsToOpOperands(operands);
     for (auto [opOperand, input] : llvm::zip(opOperands, inputs)) {
       meet(getLatticeElement(opOperand.get()),
-           *getLatticeElementFor(terminator, input));
+           *getLatticeElementFor(getProgramPointAfter(terminator), input));
       unaccounted.reset(const_cast<OpOperand &>(opOperand).getOperandNumber());
     }
   }
@@ -588,8 +601,8 @@ void AbstractSparseBackwardDataFlowAnalysis::
 }
 
 const AbstractSparseLattice *
-AbstractSparseBackwardDataFlowAnalysis::getLatticeElementFor(ProgramPoint point,
-                                                             Value value) {
+AbstractSparseBackwardDataFlowAnalysis::getLatticeElementFor(
+    ProgramPoint *point, Value value) {
   AbstractSparseLattice *state = getLatticeElement(value);
   addDependency(state, point);
   return state;

diff  --git a/mlir/lib/Analysis/DataFlowFramework.cpp b/mlir/lib/Analysis/DataFlowFramework.cpp
index a65ddc13143bae..7e83668c067652 100644
--- a/mlir/lib/Analysis/DataFlowFramework.cpp
+++ b/mlir/lib/Analysis/DataFlowFramework.cpp
@@ -37,7 +37,7 @@ GenericLatticeAnchor::~GenericLatticeAnchor() = default;
 
 AnalysisState::~AnalysisState() = default;
 
-void AnalysisState::addDependency(ProgramPoint dependent,
+void AnalysisState::addDependency(ProgramPoint *dependent,
                                   DataFlowAnalysis *analysis) {
   auto inserted = dependents.insert({dependent, analysis});
   (void)inserted;
@@ -53,7 +53,7 @@ void AnalysisState::addDependency(ProgramPoint dependent,
 void AnalysisState::dump() const { print(llvm::errs()); }
 
 //===----------------------------------------------------------------------===//
-// LatticeAnchor
+// ProgramPoint
 //===----------------------------------------------------------------------===//
 
 void ProgramPoint::print(raw_ostream &os) const {
@@ -61,12 +61,18 @@ void ProgramPoint::print(raw_ostream &os) const {
     os << "<NULL POINT>";
     return;
   }
-  if (Operation *op = llvm::dyn_cast<Operation *>(*this)) {
-    return op->print(os, OpPrintingFlags().skipRegions());
+  if (!isBlockStart()) {
+    os << "<after operation>:";
+    return getPrevOp()->print(os, OpPrintingFlags().skipRegions());
   }
-  return get<Block *>()->print(os);
+  os << "<before operation>:";
+  return getNextOp()->print(os, OpPrintingFlags().skipRegions());
 }
 
+//===----------------------------------------------------------------------===//
+// LatticeAnchor
+//===----------------------------------------------------------------------===//
+
 void LatticeAnchor::print(raw_ostream &os) const {
   if (isNull()) {
     os << "<NULL POINT>";
@@ -78,7 +84,7 @@ void LatticeAnchor::print(raw_ostream &os) const {
     return value.print(os, OpPrintingFlags().skipRegions());
   }
 
-  return get<ProgramPoint>().print(os);
+  return get<ProgramPoint *>()->print(os);
 }
 
 Location LatticeAnchor::getLoc() const {
@@ -87,10 +93,10 @@ Location LatticeAnchor::getLoc() const {
   if (auto value = llvm::dyn_cast<Value>(*this))
     return value.getLoc();
 
-  ProgramPoint pp = get<ProgramPoint>();
-  if (auto *op = llvm::dyn_cast<Operation *>(pp))
-    return op->getLoc();
-  return pp.get<Block *>()->getParent()->getLoc();
+  ProgramPoint *pp = get<ProgramPoint *>();
+  if (!pp->isBlockStart())
+    return pp->getPrevOp()->getLoc();
+  return pp->getBlock()->getParent()->getLoc();
 }
 
 //===----------------------------------------------------------------------===//
@@ -144,7 +150,8 @@ DataFlowAnalysis::~DataFlowAnalysis() = default;
 
 DataFlowAnalysis::DataFlowAnalysis(DataFlowSolver &solver) : solver(solver) {}
 
-void DataFlowAnalysis::addDependency(AnalysisState *state, ProgramPoint point) {
+void DataFlowAnalysis::addDependency(AnalysisState *state,
+                                     ProgramPoint *point) {
   state->addDependency(point, this);
 }
 

diff  --git a/mlir/lib/Dialect/Arith/Transforms/IntRangeOptimizations.cpp b/mlir/lib/Dialect/Arith/Transforms/IntRangeOptimizations.cpp
index 8005f9103b2356..521138c1f6f4cd 100644
--- a/mlir/lib/Dialect/Arith/Transforms/IntRangeOptimizations.cpp
+++ b/mlir/lib/Dialect/Arith/Transforms/IntRangeOptimizations.cpp
@@ -80,7 +80,7 @@ class DataFlowListener : public RewriterBase::Listener {
 
 protected:
   void notifyOperationErased(Operation *op) override {
-    s.eraseState(op);
+    s.eraseState(s.getProgramPointAfter(op));
     for (Value res : op->getResults())
       s.eraseState(res);
   }

diff  --git a/mlir/test/lib/Analysis/DataFlow/TestDeadCodeAnalysis.cpp b/mlir/test/lib/Analysis/DataFlow/TestDeadCodeAnalysis.cpp
index d02efaaa3fe320..2dc77c9705d350 100644
--- a/mlir/test/lib/Analysis/DataFlow/TestDeadCodeAnalysis.cpp
+++ b/mlir/test/lib/Analysis/DataFlow/TestDeadCodeAnalysis.cpp
@@ -29,7 +29,8 @@ static void printAnalysisResults(DataFlowSolver &solver, Operation *op,
         os << "  ";
         block.printAsOperand(os);
         os << " = ";
-        auto *live = solver.lookupState<Executable>(&block);
+        auto *live = solver.lookupState<Executable>(
+            solver.getProgramPointBefore(&block));
         if (live)
           os << *live;
         else
@@ -49,12 +50,14 @@ static void printAnalysisResults(DataFlowSolver &solver, Operation *op,
         }
       }
       if (!region.empty()) {
-        auto *preds = solver.lookupState<PredecessorState>(&region.front());
+        auto *preds = solver.lookupState<PredecessorState>(
+            solver.getProgramPointBefore(&region.front()));
         if (preds)
           os << "region_preds: " << *preds << "\n";
       }
     }
-    auto *preds = solver.lookupState<PredecessorState>(op);
+    auto *preds =
+        solver.lookupState<PredecessorState>(solver.getProgramPointAfter(op));
     if (preds)
       os << "op_preds: " << *preds << "\n";
   });
@@ -68,15 +71,15 @@ struct ConstantAnalysis : public DataFlowAnalysis {
 
   LogicalResult initialize(Operation *top) override {
     WalkResult result = top->walk([&](Operation *op) {
-      if (failed(visit(op)))
+      if (failed(visit(getProgramPointAfter(op))))
         return WalkResult::interrupt();
       return WalkResult::advance();
     });
     return success(!result.wasInterrupted());
   }
 
-  LogicalResult visit(ProgramPoint point) override {
-    Operation *op = point.get<Operation *>();
+  LogicalResult visit(ProgramPoint *point) override {
+    Operation *op = point->getPrevOp();
     Attribute value;
     if (matchPattern(op, m_Constant(&value))) {
       auto *constant = getOrCreate<Lattice<ConstantValue>>(op->getResult(0));

diff  --git a/mlir/test/lib/Analysis/DataFlow/TestDenseBackwardDataFlowAnalysis.cpp b/mlir/test/lib/Analysis/DataFlow/TestDenseBackwardDataFlowAnalysis.cpp
index 6794cbbbd89941..fa6223aa9168be 100644
--- a/mlir/test/lib/Analysis/DataFlow/TestDenseBackwardDataFlowAnalysis.cpp
+++ b/mlir/test/lib/Analysis/DataFlow/TestDenseBackwardDataFlowAnalysis.cpp
@@ -115,7 +115,8 @@ LogicalResult NextAccessAnalysis::visitOperation(Operation *op,
     std::optional<Value> underlyingValue =
         UnderlyingValueAnalysis::getMostUnderlyingValue(
             value, [&](Value value) {
-              return getOrCreateFor<UnderlyingValueLattice>(op, value);
+              return getOrCreateFor<UnderlyingValueLattice>(
+                  getProgramPointBefore(op), value);
             });
 
     // If the underlying value is not known yet, don't propagate.
@@ -151,7 +152,7 @@ void NextAccessAnalysis::visitCallControlFlowTransfer(
           UnderlyingValueAnalysis::getMostUnderlyingValue(
               operand, [&](Value value) {
                 return getOrCreateFor<UnderlyingValueLattice>(
-                    call.getOperation(), value);
+                    getProgramPointBefore(call.getOperation()), value);
               });
       if (!underlyingValue)
         return;
@@ -283,9 +284,8 @@ struct TestNextAccessPass
       if (!tag)
         return;
 
-      const NextAccess *nextAccess = solver.lookupState<NextAccess>(
-          op->getNextNode() == nullptr ? ProgramPoint(op->getBlock())
-                                       : op->getNextNode());
+      const NextAccess *nextAccess =
+          solver.lookupState<NextAccess>(solver.getProgramPointAfter(op));
       op->setAttr(kNextAccessAttrName,
                   makeNextAccessAttribute(op, solver, nextAccess));
 
@@ -300,9 +300,8 @@ struct TestNextAccessPass
         if (!successor.getSuccessor() || successor.getSuccessor()->empty())
           continue;
         Block &successorBlock = successor.getSuccessor()->front();
-        ProgramPoint successorPoint = successorBlock.empty()
-                                          ? ProgramPoint(&successorBlock)
-                                          : &successorBlock.front();
+        ProgramPoint *successorPoint =
+            solver.getProgramPointBefore(&successorBlock);
         entryPointNextAccess.push_back(makeNextAccessAttribute(
             op, solver, solver.lookupState<NextAccess>(successorPoint)));
       }

diff  --git a/mlir/test/lib/Analysis/DataFlow/TestDenseForwardDataFlowAnalysis.cpp b/mlir/test/lib/Analysis/DataFlow/TestDenseForwardDataFlowAnalysis.cpp
index 301d2a20978c84..89b5c835744fdb 100644
--- a/mlir/test/lib/Analysis/DataFlow/TestDenseForwardDataFlowAnalysis.cpp
+++ b/mlir/test/lib/Analysis/DataFlow/TestDenseForwardDataFlowAnalysis.cpp
@@ -117,7 +117,8 @@ LogicalResult LastModifiedAnalysis::visitOperation(
     std::optional<Value> underlyingValue =
         UnderlyingValueAnalysis::getMostUnderlyingValue(
             value, [&](Value value) {
-              return getOrCreateFor<UnderlyingValueLattice>(op, value);
+              return getOrCreateFor<UnderlyingValueLattice>(
+                  getProgramPointAfter(op), value);
             });
 
     // If the underlying value is not yet known, don't propagate yet.
@@ -157,7 +158,7 @@ void LastModifiedAnalysis::visitCallControlFlowTransfer(
           UnderlyingValueAnalysis::getMostUnderlyingValue(
               operand, [&](Value value) {
                 return getOrCreateFor<UnderlyingValueLattice>(
-                    call.getOperation(), value);
+                    getProgramPointAfter(call.getOperation()), value);
               });
       if (!underlyingValue)
         return;
@@ -243,7 +244,7 @@ struct TestLastModifiedPass
         return;
       os << "test_tag: " << tag.getValue() << ":\n";
       const LastModification *lastMods =
-          solver.lookupState<LastModification>(op);
+          solver.lookupState<LastModification>(solver.getProgramPointAfter(op));
       assert(lastMods && "expected a dense lattice");
       for (auto [index, operand] : llvm::enumerate(op->getOperands())) {
         os << " operand #" << index << "\n";

diff  --git a/mlir/test/lib/Analysis/DataFlow/TestSparseBackwardDataFlowAnalysis.cpp b/mlir/test/lib/Analysis/DataFlow/TestSparseBackwardDataFlowAnalysis.cpp
index 2445b58452bd60..1f3cab1e02adbf 100644
--- a/mlir/test/lib/Analysis/DataFlow/TestSparseBackwardDataFlowAnalysis.cpp
+++ b/mlir/test/lib/Analysis/DataFlow/TestSparseBackwardDataFlowAnalysis.cpp
@@ -108,7 +108,7 @@ WrittenToAnalysis::visitOperation(Operation *op, ArrayRef<WrittenTo *> operands,
     for (WrittenTo *operand : operands) {
       meet(operand, *r);
     }
-    addDependency(const_cast<WrittenTo *>(r), op);
+    addDependency(const_cast<WrittenTo *>(r), getProgramPointAfter(op));
   }
   return success();
 }

diff  --git a/mlir/test/lib/Analysis/TestDataFlowFramework.cpp b/mlir/test/lib/Analysis/TestDataFlowFramework.cpp
index 9573ec1d143257..3eb39fc950dadb 100644
--- a/mlir/test/lib/Analysis/TestDataFlowFramework.cpp
+++ b/mlir/test/lib/Analysis/TestDataFlowFramework.cpp
@@ -75,7 +75,7 @@ class FooAnalysis : public DataFlowAnalysis {
   using DataFlowAnalysis::DataFlowAnalysis;
 
   LogicalResult initialize(Operation *top) override;
-  LogicalResult visit(ProgramPoint point) override;
+  LogicalResult visit(ProgramPoint *point) override;
 
 private:
   void visitBlock(Block *block);
@@ -100,7 +100,8 @@ LogicalResult FooAnalysis::initialize(Operation *top) {
     return top->emitError("expected at least one block in the region");
 
   // Initialize the top-level state.
-  (void)getOrCreate<FooState>(&top->getRegion(0).front())->join(0);
+  (void)getOrCreate<FooState>(getProgramPointBefore(&top->getRegion(0).front()))
+      ->join(0);
 
   // Visit all nested blocks and operations.
   for (Block &block : top->getRegion(0)) {
@@ -114,11 +115,11 @@ LogicalResult FooAnalysis::initialize(Operation *top) {
   return success();
 }
 
-LogicalResult FooAnalysis::visit(ProgramPoint point) {
-  if (auto *op = llvm::dyn_cast_if_present<Operation *>(point))
-    visitOperation(op);
+LogicalResult FooAnalysis::visit(ProgramPoint *point) {
+  if (!point->isBlockStart())
+    visitOperation(point->getPrevOp());
   else
-    visitBlock(point.get<Block *>());
+    visitBlock(point->getBlock());
   return success();
 }
 
@@ -127,27 +128,26 @@ void FooAnalysis::visitBlock(Block *block) {
     // This is the initial state. Let the framework default-initialize it.
     return;
   }
-  FooState *state = getOrCreate<FooState>(block);
+  ProgramPoint *point = getProgramPointBefore(block);
+  FooState *state = getOrCreate<FooState>(point);
   ChangeResult result = ChangeResult::NoChange;
   for (Block *pred : block->getPredecessors()) {
     // Join the state at the terminators of all predecessors.
-    const FooState *predState =
-        getOrCreateFor<FooState>(block, pred->getTerminator());
+    const FooState *predState = getOrCreateFor<FooState>(
+        point, getProgramPointAfter(pred->getTerminator()));
     result |= state->join(*predState);
   }
   propagateIfChanged(state, result);
 }
 
 void FooAnalysis::visitOperation(Operation *op) {
-  FooState *state = getOrCreate<FooState>(op);
+  ProgramPoint *point = getProgramPointAfter(op);
+  FooState *state = getOrCreate<FooState>(point);
   ChangeResult result = ChangeResult::NoChange;
 
   // Copy the state across the operation.
   const FooState *prevState;
-  if (Operation *prev = op->getPrevNode())
-    prevState = getOrCreateFor<FooState>(op, prev);
-  else
-    prevState = getOrCreateFor<FooState>(op, op->getBlock());
+  prevState = getOrCreateFor<FooState>(point, getProgramPointBefore(op));
   result |= state->set(*prevState);
 
   // Modify the state with the attribute, if specified.
@@ -172,7 +172,8 @@ void TestFooAnalysisPass::runOnOperation() {
     auto tag = op->getAttrOfType<StringAttr>("tag");
     if (!tag)
       return;
-    const FooState *state = solver.lookupState<FooState>(op);
+    const FooState *state =
+        solver.lookupState<FooState>(solver.getProgramPointAfter(op));
     assert(state && !state->isUninitialized());
     os << tag.getValue() << " -> " << state->getValue() << "\n";
   });


        


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