lib/Support/ARMWinEH.cpp

   1 //===-- ARMWinEH.cpp - Windows on ARM EH Support Functions ------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "llvm/Support/ARMWinEH.h"
  10 #include "llvm/Support/raw_ostream.h"
  11
  12 namespace llvm {
  13 namespace ARM {
  14 namespace WinEH {
  15 std::pair<uint16_t, uint32_t> SavedRegisterMask(const RuntimeFunction &RF) {
  16   uint8_t NumRegisters = RF.Reg();
  17   uint8_t RegistersVFP = RF.R();
  18   uint8_t LinkRegister = RF.L();
  19   uint8_t ChainedFrame = RF.C();
  20
  21   uint16_t GPRMask = (ChainedFrame << 11) | (LinkRegister << 14);
  22   uint32_t VFPMask = 0;
  23
  24   if (RegistersVFP)
  25     VFPMask |= (((1 << ((NumRegisters + 1) % 8)) - 1) << 8);
  26   else
  27     GPRMask |= (((1 << (NumRegisters + 1)) - 1) << 4);
  28
  29   if (PrologueFolding(RF))
  30     GPRMask |= (((1 << (NumRegisters + 1)) - 1) << (~RF.StackAdjust() & 0x3));
  31
  32   return std::make_pair(GPRMask, VFPMask);
  33 }
  34 }
  35 }
  36 }
  37