hanchenye-llvm-project/lldb/source/Plugins/Process/POSIX/RegisterContextPOSIXProcessMonitor_arm64.cpp

//===-- RegisterContextPOSIXProcessMonitor_arm64.cpp -----------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===---------------------------------------------------------------------===//

#include "lldb/Target/Thread.h"
#include "lldb/Core/RegisterValue.h"

#include "Plugins/Process/Utility/RegisterContextPOSIX_arm64.h"
#include "ProcessPOSIX.h"
#include "RegisterContextPOSIXProcessMonitor_arm64.h"
#include "Plugins/Process/Linux/ProcessMonitor.h"

#define REG_CONTEXT_SIZE (GetGPRSize())

RegisterContextPOSIXProcessMonitor_arm64::RegisterContextPOSIXProcessMonitor_arm64(lldb_private::Thread &thread,
                                                                                   uint32_t concrete_frame_idx,
                                                                                   lldb_private::RegisterInfoInterface *register_info)
    : RegisterContextPOSIX_arm64(thread, concrete_frame_idx, register_info)
{
}

ProcessMonitor &
RegisterContextPOSIXProcessMonitor_arm64::GetMonitor()
{
    lldb::ProcessSP base = CalculateProcess();
    ProcessPOSIX *process = static_cast<ProcessPOSIX*>(base.get());
    return process->GetMonitor();
}

bool
RegisterContextPOSIXProcessMonitor_arm64::ReadGPR()
{
     ProcessMonitor &monitor = GetMonitor();
     return monitor.ReadGPR(m_thread.GetID(), &m_gpr_arm64, GetGPRSize());
}

bool
RegisterContextPOSIXProcessMonitor_arm64::ReadFPR()
{
    ProcessMonitor &monitor = GetMonitor();
    return monitor.ReadFPR(m_thread.GetID(), &m_fpr, sizeof m_fpr);
}

bool
RegisterContextPOSIXProcessMonitor_arm64::WriteGPR()
{
    ProcessMonitor &monitor = GetMonitor();
    return monitor.WriteGPR(m_thread.GetID(), &m_gpr_arm64, GetGPRSize());
}

bool
RegisterContextPOSIXProcessMonitor_arm64::WriteFPR()
{
    ProcessMonitor &monitor = GetMonitor();
    return monitor.WriteFPR(m_thread.GetID(), &m_fpr, sizeof m_fpr);
}

bool
RegisterContextPOSIXProcessMonitor_arm64::ReadRegister(const unsigned reg,
                                                       lldb_private::RegisterValue &value)
{
    ProcessMonitor &monitor = GetMonitor();
    return monitor.ReadRegisterValue(m_thread.GetID(),
                                     GetRegisterOffset(reg),
                                     GetRegisterName(reg),
                                     GetRegisterSize(reg),
                                     value);
}

bool
RegisterContextPOSIXProcessMonitor_arm64::WriteRegister(const unsigned reg,
                                                         const lldb_private::RegisterValue &value)
{
    unsigned reg_to_write = reg;
    lldb_private::RegisterValue value_to_write = value;

    // Check if this is a subregister of a full register.
    const lldb_private::RegisterInfo *reg_info = GetRegisterInfoAtIndex(reg);
    if (reg_info->invalidate_regs && (reg_info->invalidate_regs[0] != LLDB_INVALID_REGNUM))
    {
        lldb_private::RegisterValue full_value;
        uint32_t full_reg = reg_info->invalidate_regs[0];
        const lldb_private::RegisterInfo *full_reg_info = GetRegisterInfoAtIndex(full_reg);

        // Read the full register.
        if (ReadRegister(full_reg_info, full_value))
        {
            lldb_private::Error error;
            lldb::ByteOrder byte_order = GetByteOrder();
            uint8_t dst[lldb_private::RegisterValue::kMaxRegisterByteSize];

            // Get the bytes for the full register.
            const uint32_t dest_size = full_value.GetAsMemoryData (full_reg_info,
                                                                   dst,
                                                                   sizeof(dst),
                                                                   byte_order,
                                                                   error);
            if (error.Success() && dest_size)
            {
                uint8_t src[lldb_private::RegisterValue::kMaxRegisterByteSize];

                // Get the bytes for the source data.
                const uint32_t src_size = value.GetAsMemoryData (reg_info, src, sizeof(src), byte_order, error);
                if (error.Success() && src_size && (src_size < dest_size))
                {
                    // Copy the src bytes to the destination.
                    ::memcpy (dst + (reg_info->byte_offset & 0x1), src, src_size);
                    // Set this full register as the value to write.
                    value_to_write.SetBytes(dst, full_value.GetByteSize(), byte_order);
                    value_to_write.SetType(full_reg_info);
                    reg_to_write = full_reg;
                }
            }
        }
    }

    ProcessMonitor &monitor = GetMonitor();
    return monitor.WriteRegisterValue(m_thread.GetID(),
                                      GetRegisterOffset(reg_to_write),
                                      GetRegisterName(reg_to_write),
                                      value_to_write);
}

bool
RegisterContextPOSIXProcessMonitor_arm64::ReadRegister(const lldb_private::RegisterInfo *reg_info, lldb_private::RegisterValue &value)
{
    if (!reg_info)
        return false;

    const uint32_t reg = reg_info->kinds[lldb::eRegisterKindLLDB];

    if (IsFPR(reg))
    {
        if (!ReadFPR())
            return false;
    }
    else
    {
        uint32_t full_reg = reg;
        bool is_subreg = reg_info->invalidate_regs && (reg_info->invalidate_regs[0] != LLDB_INVALID_REGNUM);

        if (is_subreg)
        {
            // Read the full aligned 64-bit register.
            full_reg = reg_info->invalidate_regs[0];
        }
        return ReadRegister(full_reg, value);
    }

    // Get pointer to m_fpr variable and set the data from it.
    assert (reg_info->byte_offset < sizeof m_fpr);
    uint8_t *src = (uint8_t *)&m_fpr + reg_info->byte_offset;
    switch (reg_info->byte_size)
    {
        case 2:
            value.SetUInt16(*(uint16_t *)src);
            return true;
        case 4:
            value.SetUInt32(*(uint32_t *)src);
            return true;
        case 8:
            value.SetUInt64(*(uint64_t *)src);
            return true;
        default:
            assert(false && "Unhandled data size.");
            return false;
    }
}

bool
RegisterContextPOSIXProcessMonitor_arm64::WriteRegister(const lldb_private::RegisterInfo *reg_info, const lldb_private::RegisterValue &value)
{
    const uint32_t reg = reg_info->kinds[lldb::eRegisterKindLLDB];

    if (IsGPR(reg))
        return WriteRegister(reg, value);

    return false;
}

bool
RegisterContextPOSIXProcessMonitor_arm64::ReadAllRegisterValues(lldb::DataBufferSP &data_sp)
{
    bool success = false;
    data_sp.reset (new lldb_private::DataBufferHeap (REG_CONTEXT_SIZE, 0));
    if (data_sp && ReadGPR () && ReadFPR ())
    {
        uint8_t *dst = data_sp->GetBytes();
        success = dst != 0;

        if (success)
        {
            ::memcpy (dst, &m_gpr_arm64, GetGPRSize());
            dst += GetGPRSize();
            ::memcpy (dst, &m_fpr, sizeof m_fpr);
        }
    }
    return success;
}

bool
RegisterContextPOSIXProcessMonitor_arm64::WriteAllRegisterValues(const lldb::DataBufferSP &data_sp)
{
    bool success = false;
    if (data_sp && data_sp->GetByteSize() == REG_CONTEXT_SIZE)
    {
        uint8_t *src = data_sp->GetBytes();
        if (src)
        {
            ::memcpy (&m_gpr_arm64, src, GetGPRSize());
            if (WriteGPR()) {
                src += GetGPRSize();
                ::memcpy (&m_fpr, src, sizeof m_fpr);
                success = WriteFPR();
            }
        }
    }
    return success;
}

uint32_t
RegisterContextPOSIXProcessMonitor_arm64::SetHardwareWatchpoint(lldb::addr_t addr, size_t size,
                                                                bool read, bool write)
{
    const uint32_t num_hw_watchpoints = NumSupportedHardwareWatchpoints();
    uint32_t hw_index;

    for (hw_index = 0; hw_index < num_hw_watchpoints; ++hw_index)
    {
        if (IsWatchpointVacant(hw_index))
            return SetHardwareWatchpointWithIndex(addr, size,
                                                  read, write,
                                                  hw_index);
    }

    return LLDB_INVALID_INDEX32;
}

bool
RegisterContextPOSIXProcessMonitor_arm64::ClearHardwareWatchpoint(uint32_t hw_index)
{
    return false;
}

bool
RegisterContextPOSIXProcessMonitor_arm64::HardwareSingleStep(bool enable)
{
    return false;
}

bool
RegisterContextPOSIXProcessMonitor_arm64::UpdateAfterBreakpoint()
{
    // PC points one byte past the int3 responsible for the breakpoint.
    lldb::addr_t pc;

    if ((pc = GetPC()) == LLDB_INVALID_ADDRESS)
        return false;

    SetPC(pc - 1);
    return true;
}

unsigned
RegisterContextPOSIXProcessMonitor_arm64::GetRegisterIndexFromOffset(unsigned offset)
{
    unsigned reg;
    for (reg = 0; reg < k_num_registers_arm64; reg++)
    {
        if (GetRegisterInfo()[reg].byte_offset == offset)
            break;
    }
    assert(reg < k_num_registers_arm64 && "Invalid register offset.");
    return reg;
}

bool
RegisterContextPOSIXProcessMonitor_arm64::IsWatchpointHit(uint32_t hw_index)
{
    return false;
}

bool
RegisterContextPOSIXProcessMonitor_arm64::ClearWatchpointHits()
{
    return false;
}

lldb::addr_t
RegisterContextPOSIXProcessMonitor_arm64::GetWatchpointAddress(uint32_t hw_index)
{
    return LLDB_INVALID_ADDRESS;
}

bool
RegisterContextPOSIXProcessMonitor_arm64::IsWatchpointVacant(uint32_t hw_index)
{
    return false;
}

bool
RegisterContextPOSIXProcessMonitor_arm64::SetHardwareWatchpointWithIndex(lldb::addr_t addr, size_t size,
                                                                         bool read, bool write,
                                                                         uint32_t hw_index)
{
    return false;
}

uint32_t
RegisterContextPOSIXProcessMonitor_arm64::NumSupportedHardwareWatchpoints()
{
    return 0;
}