llvm/llvm/include/llvm/CodeGen/GlobalISel/CSEInfo.h

//===- llvm/CodeGen/GlobalISel/CSEInfo.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
/// Provides analysis for continuously CSEing during GISel passes.
///
//===----------------------------------------------------------------------===//
#ifndef LLVM_CODEGEN_GLOBALISEL_CSEINFO_H
#define LLVM_CODEGEN_GLOBALISEL_CSEINFO_H

#include "llvm/ADT/FoldingSet.h"
#include "llvm/CodeGen/CSEConfigBase.h"
#include "llvm/CodeGen/GlobalISel/GISelChangeObserver.h"
#include "llvm/CodeGen/GlobalISel/GISelWorkList.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/Support/Allocator.h"
#include "llvm/Support/CodeGen.h"

namespace llvm {
class MachineBasicBlock;

/// A class that wraps MachineInstrs and derives from FoldingSetNode in order to
/// be uniqued in a CSEMap. The tradeoff here is extra memory allocations for
/// UniqueMachineInstr vs making MachineInstr bigger.
class UniqueMachineInstr : public FoldingSetNode { … };

// A CSE config for fully optimized builds.
class CSEConfigFull : public CSEConfigBase { … };

// Commonly used for O0 config.
class CSEConfigConstantOnly : public CSEConfigBase { … };

// Returns the standard expected CSEConfig for the given optimization level.
// We have this logic here so targets can make use of it from their derived
// TargetPassConfig, but can't put this logic into TargetPassConfig directly
// because the CodeGen library can't depend on GlobalISel.
std::unique_ptr<CSEConfigBase>
getStandardCSEConfigForOpt(CodeGenOptLevel Level);

/// The CSE Analysis object.
/// This installs itself as a delegate to the MachineFunction to track
/// new instructions as well as deletions. It however will not be able to
/// track instruction mutations. In such cases, recordNewInstruction should be
/// called (for eg inside MachineIRBuilder::recordInsertion).
/// Also because of how just the instruction can be inserted without adding any
/// operands to the instruction, instructions are uniqued and inserted lazily.
/// CSEInfo should assert when trying to enter an incomplete instruction into
/// the CSEMap. There is Opcode level granularity on which instructions can be
/// CSE'd and for now, only Generic instructions are CSEable.
class GISelCSEInfo : public GISelChangeObserver { … };

class TargetRegisterClass;
class RegisterBank;

// Simple builder class to easily profile properties about MIs.
class GISelInstProfileBuilder { … };

/// Simple wrapper that does the following.
/// 1) Lazily evaluate the MachineFunction to compute CSEable instructions.
/// 2) Allows configuration of which instructions are CSEd through CSEConfig
/// object. Provides a method called get which takes a CSEConfig object.
class GISelCSEAnalysisWrapper { … };

/// The actual analysis pass wrapper.
class GISelCSEAnalysisWrapperPass : public MachineFunctionPass { … };

} // namespace llvm

#endif