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/Passes.h" 17 #include "llvm/CodeGen/TargetFrameLowering.h" 18 #include "llvm/CodeGen/TargetInstrInfo.h" 19 #include "llvm/CodeGen/TargetSubtargetInfo.h" 20 #include "llvm/IR/Function.h" 21 #include "llvm/IR/Module.h" 22 #include "llvm/InitializePasses.h" 23 24 using namespace llvm; 25 26 namespace { 27 struct FEntryInserter : public MachineFunctionPass { 28 static char ID; // Pass identification, replacement for typeid 29 FEntryInserter() : MachineFunctionPass(ID) { 30 initializeFEntryInserterPass(*PassRegistry::getPassRegistry()); 31 } 32 33 bool runOnMachineFunction(MachineFunction &F) override; 34 }; 35 } 36 37 bool FEntryInserter::runOnMachineFunction(MachineFunction &MF) { 38 const std::string FEntryName = std::string( 39 MF.getFunction().getFnAttribute("fentry-call").getValueAsString()); 40 if (FEntryName != "true") 41 return false; 42 43 auto &FirstMBB = *MF.begin(); 44 auto *TII = MF.getSubtarget().getInstrInfo(); 45 BuildMI(FirstMBB, FirstMBB.begin(), DebugLoc(), 46 TII->get(TargetOpcode::FENTRY_CALL)); 47 return true; 48 } 49 50 char FEntryInserter::ID = 0; 51 char &llvm::FEntryInserterID = FEntryInserter::ID; 52 INITIALIZE_PASS(FEntryInserter, "fentry-insert", "Insert fentry calls", false, 53 false) 54