1 //===-- FEntryInsertion.cpp - Patchable prologues for LLVM -------------===// 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-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file edits function bodies to insert fentry calls. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #include "llvm/CodeGen/MachineFunction.h" 14 #include "llvm/CodeGen/MachineFunctionPass.h" 15 #include "llvm/CodeGen/MachineInstrBuilder.h" 16 #include "llvm/CodeGen/TargetInstrInfo.h" 17 #include "llvm/CodeGen/TargetSubtargetInfo.h" 18 #include "llvm/IR/Function.h" 19 #include "llvm/InitializePasses.h" 20 21 using namespace llvm; 22 23 namespace { 24 struct FEntryInserter : public MachineFunctionPass { 25 static char ID; // Pass identification, replacement for typeid FEntryInserter__anon05c660f80111::FEntryInserter26 FEntryInserter() : MachineFunctionPass(ID) { 27 initializeFEntryInserterPass(*PassRegistry::getPassRegistry()); 28 } 29 30 bool runOnMachineFunction(MachineFunction &F) override; 31 }; 32 } 33 runOnMachineFunction(MachineFunction & MF)34bool FEntryInserter::runOnMachineFunction(MachineFunction &MF) { 35 const std::string FEntryName = std::string( 36 MF.getFunction().getFnAttribute("fentry-call").getValueAsString()); 37 if (FEntryName != "true") 38 return false; 39 40 auto &FirstMBB = *MF.begin(); 41 auto *TII = MF.getSubtarget().getInstrInfo(); 42 BuildMI(FirstMBB, FirstMBB.begin(), DebugLoc(), 43 TII->get(TargetOpcode::FENTRY_CALL)); 44 return true; 45 } 46 47 char FEntryInserter::ID = 0; 48 char &llvm::FEntryInserterID = FEntryInserter::ID; 49 INITIALIZE_PASS(FEntryInserter, "fentry-insert", "Insert fentry calls", false, 50 false) 51