1//===-- BPFTargetMachine.cpp - Define TargetMachine for BPF ---------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// Implements the info about BPF target spec. 11// 12//===----------------------------------------------------------------------===// 13 14#include "BPF.h" 15#include "BPFTargetMachine.h" 16#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h" 17#include "llvm/IR/LegacyPassManager.h" 18#include "llvm/CodeGen/Passes.h" 19#include "llvm/Support/FormattedStream.h" 20#include "llvm/Support/TargetRegistry.h" 21#include "llvm/Target/TargetOptions.h" 22using namespace llvm; 23 24extern "C" void LLVMInitializeBPFTarget() { 25 // Register the target. 26 RegisterTargetMachine<BPFTargetMachine> X(TheBPFTarget); 27} 28 29// DataLayout --> Little-endian, 64-bit pointer/ABI/alignment 30// The stack is always 8 byte aligned 31// On function prologue, the stack is created by decrementing 32// its pointer. Once decremented, all references are done with positive 33// offset from the stack/frame pointer. 34BPFTargetMachine::BPFTargetMachine(const Target &T, StringRef TT, StringRef CPU, 35 StringRef FS, const TargetOptions &Options, 36 Reloc::Model RM, CodeModel::Model CM, 37 CodeGenOpt::Level OL) 38 : LLVMTargetMachine(T, "e-m:e-p:64:64-i64:64-n32:64-S128", TT, CPU, FS, 39 Options, RM, CM, OL), 40 TLOF(make_unique<TargetLoweringObjectFileELF>()), 41 Subtarget(TT, CPU, FS, *this) { 42 initAsmInfo(); 43} 44namespace { 45// BPF Code Generator Pass Configuration Options. 46class BPFPassConfig : public TargetPassConfig { 47public: 48 BPFPassConfig(BPFTargetMachine *TM, PassManagerBase &PM) 49 : TargetPassConfig(TM, PM) {} 50 51 BPFTargetMachine &getBPFTargetMachine() const { 52 return getTM<BPFTargetMachine>(); 53 } 54 55 bool addInstSelector() override; 56}; 57} 58 59TargetPassConfig *BPFTargetMachine::createPassConfig(PassManagerBase &PM) { 60 return new BPFPassConfig(this, PM); 61} 62 63// Install an instruction selector pass using 64// the ISelDag to gen BPF code. 65bool BPFPassConfig::addInstSelector() { 66 addPass(createBPFISelDag(getBPFTargetMachine())); 67 68 return false; 69} 70