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
11namespace llvm {
12namespace ARM {
13namespace WinEH {
14std::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(x&: GPRMask, y&: VFPMask);
45}
46} // namespace WinEH
47} // namespace ARM
48} // namespace llvm
49
50