llvm/llvm/lib/Target/PowerPC/PPCPreEmitPeephole.cpp

//===--------- PPCPreEmitPeephole.cpp - Late peephole optimizations -------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// A pre-emit peephole for catching opportunities introduced by late passes such
// as MachineBlockPlacement.
//
//===----------------------------------------------------------------------===//

#include "PPC.h"
#include "PPCInstrInfo.h"
#include "PPCSubtarget.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/CodeGen/LivePhysRegs.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/RegisterScavenging.h"
#include "llvm/MC/MCContext.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"

usingnamespacellvm;

#define DEBUG_TYPE …

STATISTIC(NumRRConvertedInPreEmit,
          "Number of r+r instructions converted to r+i in pre-emit peephole");
STATISTIC(NumRemovedInPreEmit,
          "Number of instructions deleted in pre-emit peephole");
STATISTIC(NumberOfSelfCopies,
          "Number of self copy instructions eliminated");
STATISTIC(NumFrameOffFoldInPreEmit,
          "Number of folding frame offset by using r+r in pre-emit peephole");
STATISTIC(NumCmpsInPreEmit,
          "Number of compares eliminated in pre-emit peephole");

static cl::opt<bool>
EnablePCRelLinkerOpt("ppc-pcrel-linker-opt", cl::Hidden, cl::init(true),
                     cl::desc("enable PC Relative linker optimization"));

static cl::opt<bool>
RunPreEmitPeephole("ppc-late-peephole", cl::Hidden, cl::init(true),
                   cl::desc("Run pre-emit peephole optimizations."));

static cl::opt<uint64_t>
DSCRValue("ppc-set-dscr", cl::Hidden,
          cl::desc("Set the Data Stream Control Register."));

namespace {

static bool hasPCRelativeForm(MachineInstr &Use) { … }

  class PPCPreEmitPeephole : public MachineFunctionPass { … };
}

INITIALIZE_PASS(…)
char PPCPreEmitPeephole::ID = …;

FunctionPass *llvm::createPPCPreEmitPeepholePass() { … }