llvm/mlir/include/mlir/Analysis/DataFlow/IntegerRangeAnalysis.h

//===-IntegerRangeAnalysis.h - Integer range analysis -----------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file declares the dataflow analysis class for integer range inference
// so that it can be used in transformations over the `arith` dialect such as
// branch elimination or signed->unsigned rewriting.
//
// One can also implement InferIntRangeInterface on ops in custom dialects,
// and then use this analysis to propagate ranges with custom semantics.
//
//===----------------------------------------------------------------------===//

#ifndef MLIR_ANALYSIS_DATAFLOW_INTEGERANGEANALYSIS_H
#define MLIR_ANALYSIS_DATAFLOW_INTEGERANGEANALYSIS_H

#include "mlir/Analysis/DataFlow/SparseAnalysis.h"
#include "mlir/Interfaces/InferIntRangeInterface.h"

namespace mlir {
namespace dataflow {

/// This lattice element represents the integer value range of an SSA value.
/// When this lattice is updated, it automatically updates the constant value
/// of the SSA value (if the range can be narrowed to one).
class IntegerValueRangeLattice : public Lattice<IntegerValueRange> { … };

/// Integer range analysis determines the integer value range of SSA values
/// using operations that define `InferIntRangeInterface` and also sets the
/// range of iteration indices of loops with known bounds.
///
/// This analysis depends on DeadCodeAnalysis, and will be a silent no-op
/// if DeadCodeAnalysis is not loaded in the same solver context.
class IntegerRangeAnalysis
    : public SparseForwardDataFlowAnalysis<IntegerValueRangeLattice> { … };

} // end namespace dataflow
} // end namespace mlir

#endif // MLIR_ANALYSIS_DATAFLOW_INTEGERANGEANALYSIS_H