llvm-project/llvm/lib/Target/BPF/BPFTargetMachine.cpp
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00

117 lines
4.0 KiB
C++

//===-- BPFTargetMachine.cpp - Define TargetMachine for BPF ---------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// Implements the info about BPF target spec.
//
//===----------------------------------------------------------------------===//
#include "BPFTargetMachine.h"
#include "BPF.h"
#include "MCTargetDesc/BPFMCAsmInfo.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
#include "llvm/CodeGen/TargetPassConfig.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/Support/FormattedStream.h"
#include "llvm/Support/TargetRegistry.h"
#include "llvm/Target/TargetOptions.h"
using namespace llvm;
static cl::
opt<bool> DisableMIPeephole("disable-bpf-peephole", cl::Hidden,
cl::desc("Disable machine peepholes for BPF"));
extern "C" void LLVMInitializeBPFTarget() {
// Register the target.
RegisterTargetMachine<BPFTargetMachine> X(getTheBPFleTarget());
RegisterTargetMachine<BPFTargetMachine> Y(getTheBPFbeTarget());
RegisterTargetMachine<BPFTargetMachine> Z(getTheBPFTarget());
PassRegistry &PR = *PassRegistry::getPassRegistry();
initializeBPFMIPeepholePass(PR);
}
// DataLayout: little or big endian
static std::string computeDataLayout(const Triple &TT) {
if (TT.getArch() == Triple::bpfeb)
return "E-m:e-p:64:64-i64:64-n32:64-S128";
else
return "e-m:e-p:64:64-i64:64-n32:64-S128";
}
static Reloc::Model getEffectiveRelocModel(Optional<Reloc::Model> RM) {
if (!RM.hasValue())
return Reloc::PIC_;
return *RM;
}
BPFTargetMachine::BPFTargetMachine(const Target &T, const Triple &TT,
StringRef CPU, StringRef FS,
const TargetOptions &Options,
Optional<Reloc::Model> RM,
Optional<CodeModel::Model> CM,
CodeGenOpt::Level OL, bool JIT)
: LLVMTargetMachine(T, computeDataLayout(TT), TT, CPU, FS, Options,
getEffectiveRelocModel(RM),
getEffectiveCodeModel(CM, CodeModel::Small), OL),
TLOF(make_unique<TargetLoweringObjectFileELF>()),
Subtarget(TT, CPU, FS, *this) {
initAsmInfo();
BPFMCAsmInfo *MAI =
static_cast<BPFMCAsmInfo *>(const_cast<MCAsmInfo *>(AsmInfo.get()));
MAI->setDwarfUsesRelocationsAcrossSections(!Subtarget.getUseDwarfRIS());
}
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;
void addMachineSSAOptimization() override;
void addPreEmitPass() 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;
}
void BPFPassConfig::addMachineSSAOptimization() {
// The default implementation must be called first as we want eBPF
// Peephole ran at last.
TargetPassConfig::addMachineSSAOptimization();
const BPFSubtarget *Subtarget = getBPFTargetMachine().getSubtargetImpl();
if (Subtarget->getHasAlu32() && !DisableMIPeephole)
addPass(createBPFMIPeepholePass());
}
void BPFPassConfig::addPreEmitPass() {
const BPFSubtarget *Subtarget = getBPFTargetMachine().getSubtargetImpl();
addPass(createBPFMIPreEmitCheckingPass());
if (getOptLevel() != CodeGenOpt::None)
if (Subtarget->getHasAlu32() && !DisableMIPeephole)
addPass(createBPFMIPreEmitPeepholePass());
}