llvm/llvm/lib/Target/Hexagon/HexagonCopyHoisting.cpp

//===--------- HexagonCopyHoisting.cpp - Hexagon Copy Hoisting  ----------===//
//
// 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
//
//===----------------------------------------------------------------------===//
// The purpose of this pass is to move the copy instructions that are
// present in all the successor of a basic block (BB) to the end of BB.
//===----------------------------------------------------------------------===//

#include "HexagonTargetMachine.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/PostOrderIterator.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/Twine.h"
#include "llvm/CodeGen/LiveInterval.h"
#include "llvm/CodeGen/LiveIntervals.h"
#include "llvm/CodeGen/MachineDominators.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"

#define DEBUG_TYPE …

usingnamespacellvm;

static cl::opt<std::string> CPHoistFn("cphoistfn", cl::Hidden, cl::desc(""),
                                      cl::init(""));

namespace llvm {
void initializeHexagonCopyHoistingPass(PassRegistry &Registry);
FunctionPass *createHexagonCopyHoisting();
} // namespace llvm

namespace {

class HexagonCopyHoisting : public MachineFunctionPass { … };

} // namespace

char HexagonCopyHoisting::ID = …;

namespace llvm {
char &HexagonCopyHoistingID = …;
} // namespace llvm

bool HexagonCopyHoisting::runOnMachineFunction(MachineFunction &Fn) { … }

//===----------------------------------------------------------------------===//
// Save all COPY instructions for each basic block in CopyMIList vector.
//===----------------------------------------------------------------------===//
void HexagonCopyHoisting::collectCopyInst() { … }

void HexagonCopyHoisting::addMItoCopyList(MachineInstr *MI) { … }

//===----------------------------------------------------------------------===//
// Look at the COPY instructions of all the successors of BB. If the same
// instruction is present in every successor and can be safely moved,
// pull it into BB.
//===----------------------------------------------------------------------===//
bool HexagonCopyHoisting::analyzeCopy(MachineBasicBlock *BB) { … }

bool HexagonCopyHoisting::isSafetoMove(MachineInstr *CandMI) { … }

void HexagonCopyHoisting::moveCopyInstr(MachineBasicBlock *DestBB,
                                        std::pair<Register, Register> Key,
                                        MachineInstr *MI) { … }

//===----------------------------------------------------------------------===//
//                         Public Constructor Functions
//===----------------------------------------------------------------------===//

INITIALIZE_PASS(…)

FunctionPass *llvm::createHexagonCopyHoisting() { … }