96 lines · cpp
1//===- MachineCFGPrinter.cpp - DOT Printer for Machine Functions ----------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//===----------------------------------------------------------------------===//9//10// This file defines the `-dot-machine-cfg` analysis pass, which emits11// Machine Function in DOT format in file titled `<prefix>.<function-name>.dot.12//===----------------------------------------------------------------------===//13 14#include "llvm/CodeGen/MachineCFGPrinter.h"15#include "llvm/CodeGen/MachineBasicBlock.h"16#include "llvm/CodeGen/MachineFunctionPass.h"17#include "llvm/CodeGen/TargetSubtargetInfo.h"18#include "llvm/InitializePasses.h"19#include "llvm/Pass.h"20#include "llvm/PassRegistry.h"21#include "llvm/Support/GraphWriter.h"22 23using namespace llvm;24 25#define DEBUG_TYPE "dot-machine-cfg"26 27static cl::opt<std::string>28 MCFGFuncName("mcfg-func-name", cl::Hidden,29 cl::desc("The name of a function (or its substring)"30 " whose CFG is viewed/printed."));31 32static cl::opt<std::string> MCFGDotFilenamePrefix(33 "mcfg-dot-filename-prefix", cl::Hidden,34 cl::desc("The prefix used for the Machine CFG dot file names."));35 36static cl::opt<bool>37 CFGOnly("dot-mcfg-only", cl::init(false), cl::Hidden,38 cl::desc("Print only the CFG without blocks body"));39 40static void writeMCFGToDotFile(MachineFunction &MF) {41 std::string Filename =42 (MCFGDotFilenamePrefix + "." + MF.getName() + ".dot").str();43 errs() << "Writing '" << Filename << "'...";44 45 std::error_code EC;46 raw_fd_ostream File(Filename, EC, sys::fs::OF_Text);47 48 DOTMachineFuncInfo MCFGInfo(&MF);49 50 if (!EC)51 WriteGraph(File, &MCFGInfo, CFGOnly);52 else53 errs() << " error opening file for writing!";54 errs() << '\n';55}56 57namespace {58 59class MachineCFGPrinter : public MachineFunctionPass {60public:61 static char ID;62 63 MachineCFGPrinter();64 65 bool runOnMachineFunction(MachineFunction &MF) override;66 67 void getAnalysisUsage(AnalysisUsage &AU) const override {68 AU.setPreservesCFG();69 MachineFunctionPass::getAnalysisUsage(AU);70 }71};72 73} // namespace74 75char MachineCFGPrinter::ID = 0;76 77char &llvm::MachineCFGPrinterID = MachineCFGPrinter::ID;78 79INITIALIZE_PASS(MachineCFGPrinter, DEBUG_TYPE, "Machine CFG Printer Pass",80 false, true)81 82/// Default construct and initialize the pass.83MachineCFGPrinter::MachineCFGPrinter() : MachineFunctionPass(ID) {84 initializeMachineCFGPrinterPass(*PassRegistry::getPassRegistry());85}86 87bool MachineCFGPrinter::runOnMachineFunction(MachineFunction &MF) {88 if (!MCFGFuncName.empty() && !MF.getName().contains(MCFGFuncName))89 return false;90 errs() << "Writing Machine CFG for function ";91 errs().write_escaped(MF.getName()) << '\n';92 93 writeMCFGToDotFile(MF);94 return false;95}96