DirectXShaderCompiler/lib/Support/ARMWinEH.cpp

//===-- ARMWinEH.cpp - Windows on ARM EH Support Functions ------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#include "llvm/Support/ARMWinEH.h"
#include "llvm/Support/raw_ostream.h"

namespace llvm {
namespace ARM {
namespace WinEH {
std::pair<uint16_t, uint32_t> SavedRegisterMask(const RuntimeFunction &RF) {
  uint8_t NumRegisters = RF.Reg();
  uint8_t RegistersVFP = RF.R();
  uint8_t LinkRegister = RF.L();
  uint8_t ChainedFrame = RF.C();

  uint16_t GPRMask = (ChainedFrame << 11) | (LinkRegister << 14);
  uint32_t VFPMask = 0;

  if (RegistersVFP)
    VFPMask |= (((1 << ((NumRegisters + 1) % 8)) - 1) << 8);
  else
    GPRMask |= (((1 << (NumRegisters + 1)) - 1) << 4);

  if (PrologueFolding(RF))
    GPRMask |= (((1 << (NumRegisters + 1)) - 1) << (~RF.StackAdjust() & 0x3));

  return std::make_pair(GPRMask, VFPMask);
}
}
}
}