| //===-- EHContGuardCatchret.cpp - Catchret target symbols -------*- 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 |
| // |
| //===----------------------------------------------------------------------===// |
| /// |
| /// \file |
| /// This file contains a machine function pass to insert a symbol before each |
| /// valid catchret target and store this in the MachineFunction's |
| /// CatchRetTargets vector. This will be used to emit the table of valid targets |
| /// used by EHCont Guard. |
| /// |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/ADT/Statistic.h" |
| #include "llvm/CodeGen/MachineBasicBlock.h" |
| #include "llvm/CodeGen/MachineFunctionPass.h" |
| #include "llvm/CodeGen/MachineInstr.h" |
| #include "llvm/CodeGen/MachineModuleInfo.h" |
| #include "llvm/CodeGen/MachineOperand.h" |
| #include "llvm/CodeGen/Passes.h" |
| #include "llvm/InitializePasses.h" |
| |
| using namespace llvm; |
| |
| #define DEBUG_TYPE "ehcontguard-catchret" |
| |
| STATISTIC(EHContGuardCatchretTargets, |
| "Number of EHCont Guard catchret targets"); |
| |
| namespace { |
| |
| /// MachineFunction pass to insert a symbol before each valid catchret target |
| /// and store these in the MachineFunction's CatchRetTargets vector. |
| class EHContGuardCatchret : public MachineFunctionPass { |
| public: |
| static char ID; |
| |
| EHContGuardCatchret() : MachineFunctionPass(ID) { |
| initializeEHContGuardCatchretPass(*PassRegistry::getPassRegistry()); |
| } |
| |
| StringRef getPassName() const override { |
| return "EH Cont Guard catchret targets"; |
| } |
| |
| bool runOnMachineFunction(MachineFunction &MF) override; |
| }; |
| |
| } // end anonymous namespace |
| |
| char EHContGuardCatchret::ID = 0; |
| |
| INITIALIZE_PASS(EHContGuardCatchret, "EHContGuardCatchret", |
| "Insert symbols at valid catchret targets for /guard:ehcont", |
| false, false) |
| FunctionPass *llvm::createEHContGuardCatchretPass() { |
| return new EHContGuardCatchret(); |
| } |
| |
| bool EHContGuardCatchret::runOnMachineFunction(MachineFunction &MF) { |
| |
| // Skip modules for which the ehcontguard flag is not set. |
| if (!MF.getMMI().getModule()->getModuleFlag("ehcontguard")) |
| return false; |
| |
| // Skip functions that do not have catchret |
| if (!MF.hasEHCatchret()) |
| return false; |
| |
| bool Result = false; |
| |
| for (MachineBasicBlock &MBB : MF) { |
| if (MBB.isEHCatchretTarget()) { |
| MF.addCatchretTarget(MBB.getEHCatchretSymbol()); |
| EHContGuardCatchretTargets++; |
| Result = true; |
| } |
| } |
| |
| return Result; |
| } |