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 11 namespace llvm { 12 namespace ARM { 13 namespace WinEH { 14 std::pair<uint16_t, uint32_t> SavedRegisterMask(const RuntimeFunction &RF, 15 bool Prologue) { 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); 22 uint32_t VFPMask = 0; 23 24 if (Prologue) { 25 GPRMask |= (LinkRegister << 14); 26 } else { 27 // If Ret != 0, we pop into Lr and return later 28 if (RF.Ret() != ReturnType::RT_POP) 29 GPRMask |= (LinkRegister << 14); 30 else if (!RF.H()) // If H == 0, we pop directly into Pc 31 GPRMask |= (LinkRegister << 15); 32 // else, Ret == 0 && H == 1, we pop into Pc separately afterwards 33 } 34 35 if (RegistersVFP) 36 VFPMask |= (((1 << ((NumRegisters + 1) % 8)) - 1) << 8); 37 else 38 GPRMask |= (((1 << (NumRegisters + 1)) - 1) << 4); 39 40 if ((PrologueFolding(RF) && Prologue) || (EpilogueFolding(RF) && !Prologue)) 41 GPRMask |= (((1 << ((RF.StackAdjust() & 0x3) + 1)) - 1) 42 << (~RF.StackAdjust() & 0x3)); 43 44 return std::make_pair(GPRMask, VFPMask); 45 } 46 } // namespace WinEH 47 } // namespace ARM 48 } // namespace llvm 49 50