//===- llvm/CodeGen/GlobalISel/CombinerInfo.h ------*- 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
 
//
 
//===----------------------------------------------------------------------===//
 
/// \file
 
/// Interface for Targets to specify which operations are combined how and when.
 
///
 
//===----------------------------------------------------------------------===//
 
 
 
#ifndef LLVM_CODEGEN_GLOBALISEL_COMBINERINFO_H
 
#define LLVM_CODEGEN_GLOBALISEL_COMBINERINFO_H
 
 
 
#include <cassert>
 
namespace llvm {
 
 
 
class GISelChangeObserver;
 
class LegalizerInfo;
 
class MachineInstr;
 
class MachineIRBuilder;
 
 
 
// Contains information relevant to enabling/disabling various combines for a
 
// pass.
 
class CombinerInfo {
 
public:
 
  CombinerInfo(bool AllowIllegalOps, bool ShouldLegalizeIllegal,
 
               const LegalizerInfo *LInfo, bool OptEnabled, bool OptSize,
 
               bool MinSize)
 
      : IllegalOpsAllowed(AllowIllegalOps),
 
        LegalizeIllegalOps(ShouldLegalizeIllegal), LInfo(LInfo),
 
        EnableOpt(OptEnabled), EnableOptSize(OptSize), EnableMinSize(MinSize) {
 
    assert(((AllowIllegalOps || !LegalizeIllegalOps) || LInfo) &&
 
           "Expecting legalizerInfo when illegalops not allowed");
 
  }
 
  virtual ~CombinerInfo() = default;
 
  /// If \p IllegalOpsAllowed is false, the CombinerHelper will make use of
 
  /// the legalizerInfo to check for legality before each transformation.
 
  bool IllegalOpsAllowed; // TODO: Make use of this.
 
 
 
  /// If \p LegalizeIllegalOps is true, the Combiner will also legalize the
 
  /// illegal ops that are created.
 
  bool LegalizeIllegalOps; // TODO: Make use of this.
 
  const LegalizerInfo *LInfo;
 
 
 
  /// Whether optimizations should be enabled. This is to distinguish between
 
  /// uses of the combiner unconditionally and only when optimizations are
 
  /// specifically enabled/
 
  bool EnableOpt;
 
  /// Whether we're optimizing for size.
 
  bool EnableOptSize;
 
  /// Whether we're optimizing for minsize (-Oz).
 
  bool EnableMinSize;
 
 
 
  /// Attempt to combine instructions using MI as the root.
 
  ///
 
  /// Use Observer to report the creation, modification, and erasure of
 
  /// instructions. GISelChangeObserver will automatically report certain
 
  /// kinds of operations. These operations are:
 
  /// * Instructions that are newly inserted into the MachineFunction
 
  /// * Instructions that are erased from the MachineFunction.
 
  ///
 
  /// However, it is important to report instruction modification and this is
 
  /// not automatic.
 
  virtual bool combine(GISelChangeObserver &Observer, MachineInstr &MI,
 
                       MachineIRBuilder &B) const = 0;
 
};
 
} // namespace llvm
 
 
 
#endif