llvm-mirror/lib/Target/ARM/ARMCallLowering.cpp

//===-- llvm/lib/Target/ARM/ARMCallLowering.cpp - Call lowering -----------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
///
/// \file
/// This file implements the lowering of LLVM calls to machine code calls for
/// GlobalISel.
///
//===----------------------------------------------------------------------===//

#include "ARMCallLowering.h"

#include "ARMBaseInstrInfo.h"
#include "ARMISelLowering.h"

#include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h"

using namespace llvm;

#ifndef LLVM_BUILD_GLOBAL_ISEL
#error "This shouldn't be built without GISel"
#endif

ARMCallLowering::ARMCallLowering(const ARMTargetLowering &TLI)
    : CallLowering(&TLI) {}

bool ARMCallLowering::lowerReturn(MachineIRBuilder &MIRBuilder,
                                  const Value *Val, unsigned VReg) const {
  // We're currently only handling void returns
  if (Val != nullptr)
    return false;

  AddDefaultPred(MIRBuilder.buildInstr(ARM::BX_RET));

  return true;
}

bool ARMCallLowering::lowerFormalArguments(MachineIRBuilder &MIRBuilder,
                                           const Function &F,
                                           ArrayRef<unsigned> VRegs) const {
  return F.arg_empty();
}