llvm-project/llvm/lib/CodeGen/MachineLoopInfo.cpp

46 lines
1.6 KiB
C++

//===- MachineLoopInfo.cpp - Natural Loop Calculator ----------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the MachineLoopInfo class that is used to identify natural
// loops and determine the loop depth of various nodes of the CFG. Note that
// the loops identified may actually be several natural loops that share the
// same header node... not just a single natural loop.
//
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/MachineLoopInfo.h"
#include "llvm/CodeGen/MachineDominators.h"
#include "llvm/CodeGen/Passes.h"
using namespace llvm;
#define MLB class LoopBase<MachineBasicBlock, MachineLoop>
TEMPLATE_INSTANTIATION(MLB);
#undef MLB
#define MLIB class LoopInfoBase<MachineBasicBlock, MachineLoop>
TEMPLATE_INSTANTIATION(MLIB);
#undef MLIB
char MachineLoopInfo::ID = 0;
static RegisterPass<MachineLoopInfo>
X("machine-loops", "Machine Natural Loop Construction", true);
const PassInfo *const llvm::MachineLoopInfoID = &X;
bool MachineLoopInfo::runOnMachineFunction(MachineFunction &) {
releaseMemory();
LI.Calculate(getAnalysis<MachineDominatorTree>().getBase()); // Update
return false;
}
void MachineLoopInfo::getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesAll();
AU.addRequired<MachineDominatorTree>();
MachineFunctionPass::getAnalysisUsage(AU);
}