llvm-project/llvm/lib/Target/BPF/BPFTargetMachine.cpp

70 lines
2.3 KiB
C++

//===-- BPFTargetMachine.cpp - Define TargetMachine for BPF ---------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Implements the info about BPF target spec.
//
//===----------------------------------------------------------------------===//
#include "BPF.h"
#include "BPFTargetMachine.h"
#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/Support/FormattedStream.h"
#include "llvm/Support/TargetRegistry.h"
#include "llvm/Target/TargetOptions.h"
using namespace llvm;
extern "C" void LLVMInitializeBPFTarget() {
// Register the target.
RegisterTargetMachine<BPFTargetMachine> X(TheBPFTarget);
}
// DataLayout --> Little-endian, 64-bit pointer/ABI/alignment
// The stack is always 8 byte aligned
// On function prologue, the stack is created by decrementing
// its pointer. Once decremented, all references are done with positive
// offset from the stack/frame pointer.
BPFTargetMachine::BPFTargetMachine(const Target &T, StringRef TT, StringRef CPU,
StringRef FS, const TargetOptions &Options,
Reloc::Model RM, CodeModel::Model CM,
CodeGenOpt::Level OL)
: LLVMTargetMachine(T, "e-m:e-p:64:64-i64:64-n32:64-S128", TT, CPU, FS,
Options, RM, CM, OL),
TLOF(make_unique<TargetLoweringObjectFileELF>()),
Subtarget(TT, CPU, FS, *this) {
initAsmInfo();
}
namespace {
// BPF Code Generator Pass Configuration Options.
class BPFPassConfig : public TargetPassConfig {
public:
BPFPassConfig(BPFTargetMachine *TM, PassManagerBase &PM)
: TargetPassConfig(TM, PM) {}
BPFTargetMachine &getBPFTargetMachine() const {
return getTM<BPFTargetMachine>();
}
bool addInstSelector() override;
};
}
TargetPassConfig *BPFTargetMachine::createPassConfig(PassManagerBase &PM) {
return new BPFPassConfig(this, PM);
}
// Install an instruction selector pass using
// the ISelDag to gen BPF code.
bool BPFPassConfig::addInstSelector() {
addPass(createBPFISelDag(getBPFTargetMachine()));
return false;
}