llvm/llvm/lib/CodeGen/SpillPlacement.h

//===- SpillPlacement.h - Optimal Spill Code Placement ---------*- 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 analysis computes the optimal spill code placement between basic blocks.
//
// The runOnMachineFunction() method only precomputes some profiling information
// about the CFG. The real work is done by prepare(), addConstraints(), and
// finish() which are called by the register allocator.
//
// Given a variable that is live across multiple basic blocks, and given
// constraints on the basic blocks where the variable is live, determine which
// edge bundles should have the variable in a register and which edge bundles
// should have the variable in a stack slot.
//
// The returned bit vector can be used to place optimal spill code at basic
// block entries and exits. Spill code placement inside a basic block is not
// considered.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_LIB_CODEGEN_SPILLPLACEMENT_H
#define LLVM_LIB_CODEGEN_SPILLPLACEMENT_H

#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/SparseSet.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/Support/BlockFrequency.h"

namespace llvm {

class BitVector;
class EdgeBundles;
class MachineBlockFrequencyInfo;
class MachineFunction;

class SpillPlacement : public MachineFunctionPass { … };

} // end namespace llvm

#endif // LLVM_LIB_CODEGEN_SPILLPLACEMENT_H