//===-- RegisterContextDarwin_i386.cpp --------------------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//


// C Includes
#include <stddef.h>  // offsetof

// C++ Includes
// Other libraries and framework includes
#include "lldb/Core/DataBufferHeap.h"
#include "lldb/Core/DataExtractor.h"
#include "lldb/Core/Log.h"
#include "lldb/Core/RegisterValue.h"
#include "lldb/Core/Scalar.h"
#include "lldb/Host/Endian.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Support/Compiler.h"

// Support building against older versions of LLVM, this macro was added
// recently.
#ifndef LLVM_EXTENSION
#define LLVM_EXTENSION
#endif

// Project includes
#include "RegisterContextDarwin_i386.h"

using namespace lldb;
using namespace lldb_private;

enum
{
    gpr_eax = 0,
    gpr_ebx,
    gpr_ecx,
    gpr_edx,
    gpr_edi,
    gpr_esi,
    gpr_ebp,
    gpr_esp,
    gpr_ss,
    gpr_eflags,
    gpr_eip,
    gpr_cs,
    gpr_ds,
    gpr_es,
    gpr_fs,
    gpr_gs,

    fpu_fcw,
    fpu_fsw,
    fpu_ftw,
    fpu_fop,
    fpu_ip,
    fpu_cs,
    fpu_dp,
    fpu_ds,
    fpu_mxcsr,
    fpu_mxcsrmask,
    fpu_stmm0,
    fpu_stmm1,
    fpu_stmm2,
    fpu_stmm3,
    fpu_stmm4,
    fpu_stmm5,
    fpu_stmm6,
    fpu_stmm7,
    fpu_xmm0,
    fpu_xmm1,
    fpu_xmm2,
    fpu_xmm3,
    fpu_xmm4,
    fpu_xmm5,
    fpu_xmm6,
    fpu_xmm7,

    exc_trapno,
    exc_err,
    exc_faultvaddr,

    k_num_registers,

    // Aliases
    fpu_fctrl = fpu_fcw,
    fpu_fstat = fpu_fsw,
    fpu_ftag  = fpu_ftw,
    fpu_fiseg = fpu_cs,
    fpu_fioff = fpu_ip,
    fpu_foseg = fpu_ds,
    fpu_fooff = fpu_dp
};

enum
{
    ehframe_eax = 0,
    ehframe_ecx,
    ehframe_edx,
    ehframe_ebx,
    ehframe_ebp,
    ehframe_esp,
    ehframe_esi,
    ehframe_edi,
    ehframe_eip,
    ehframe_eflags
};

enum
{
    dwarf_eax = 0,
    dwarf_ecx,
    dwarf_edx,
    dwarf_ebx,
    dwarf_esp,
    dwarf_ebp,
    dwarf_esi,
    dwarf_edi,
    dwarf_eip,
    dwarf_eflags,
    dwarf_stmm0 = 11,
    dwarf_stmm1,
    dwarf_stmm2,
    dwarf_stmm3,
    dwarf_stmm4,
    dwarf_stmm5,
    dwarf_stmm6,
    dwarf_stmm7,
    dwarf_xmm0 = 21,
    dwarf_xmm1,
    dwarf_xmm2,
    dwarf_xmm3,
    dwarf_xmm4,
    dwarf_xmm5,
    dwarf_xmm6,
    dwarf_xmm7
};


#define GPR_OFFSET(reg) (LLVM_EXTENSION offsetof (RegisterContextDarwin_i386::GPR, reg))
#define FPU_OFFSET(reg) (LLVM_EXTENSION offsetof (RegisterContextDarwin_i386::FPU, reg) + sizeof (RegisterContextDarwin_i386::GPR))
#define EXC_OFFSET(reg) (LLVM_EXTENSION offsetof (RegisterContextDarwin_i386::EXC, reg) + sizeof (RegisterContextDarwin_i386::GPR) + sizeof (RegisterContextDarwin_i386::FPU))

// These macros will auto define the register name, alt name, register size,
// register offset, encoding, format and native register. This ensures that
// the register state structures are defined correctly and have the correct
// sizes and offsets.
#define DEFINE_GPR(reg, alt)    #reg, alt, sizeof(((RegisterContextDarwin_i386::GPR *)NULL)->reg), GPR_OFFSET(reg), eEncodingUint, eFormatHex
#define DEFINE_FPU_UINT(reg)    #reg, NULL, sizeof(((RegisterContextDarwin_i386::FPU *)NULL)->reg), FPU_OFFSET(reg), eEncodingUint, eFormatHex
#define DEFINE_FPU_VECT(reg, i) #reg#i, NULL, sizeof(((RegisterContextDarwin_i386::FPU *)NULL)->reg[i].bytes), FPU_OFFSET(reg[i]), eEncodingVector, eFormatVectorOfUInt8, { LLDB_INVALID_REGNUM, dwarf_##reg##i, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, fpu_##reg##i }, NULL, NULL

#define DEFINE_EXC(reg)         #reg, NULL, sizeof(((RegisterContextDarwin_i386::EXC *)NULL)->reg), EXC_OFFSET(reg), eEncodingUint, eFormatHex
#define REG_CONTEXT_SIZE (sizeof (RegisterContextDarwin_i386::GPR) + sizeof (RegisterContextDarwin_i386::FPU) + sizeof (RegisterContextDarwin_i386::EXC))

static RegisterInfo g_register_infos[] =
{
//  Macro auto defines most stuff   eh_frame                DWARF                 GENERIC                    PROCESS PLUGIN       LLDB              VALUE REGS    INVALIDATE REGS
//  =============================== ======================= ===================   =========================  ==================   ================= ==========    ===============
    { DEFINE_GPR(eax    , NULL)     , { ehframe_eax        , dwarf_eax          , LLDB_INVALID_REGNUM       , LLDB_INVALID_REGNUM, gpr_eax      },      NULL,              NULL},
    { DEFINE_GPR(ebx    , NULL)     , { ehframe_ebx        , dwarf_ebx          , LLDB_INVALID_REGNUM       , LLDB_INVALID_REGNUM, gpr_ebx      },      NULL,              NULL},
    { DEFINE_GPR(ecx    , NULL)     , { ehframe_ecx        , dwarf_ecx          , LLDB_INVALID_REGNUM       , LLDB_INVALID_REGNUM, gpr_ecx      },      NULL,              NULL},
    { DEFINE_GPR(edx    , NULL)     , { ehframe_edx        , dwarf_edx          , LLDB_INVALID_REGNUM       , LLDB_INVALID_REGNUM, gpr_edx      },      NULL,              NULL},
    { DEFINE_GPR(edi    , NULL)     , { ehframe_edi        , dwarf_edi          , LLDB_INVALID_REGNUM       , LLDB_INVALID_REGNUM, gpr_edi      },      NULL,              NULL},
    { DEFINE_GPR(esi    , NULL)     , { ehframe_esi        , dwarf_esi          , LLDB_INVALID_REGNUM       , LLDB_INVALID_REGNUM, gpr_esi      },      NULL,              NULL},
    { DEFINE_GPR(ebp    , "fp")     , { ehframe_ebp        , dwarf_ebp          , LLDB_REGNUM_GENERIC_FP    , LLDB_INVALID_REGNUM, gpr_ebp      },      NULL,              NULL},
    { DEFINE_GPR(esp    , "sp")     , { ehframe_esp        , dwarf_esp          , LLDB_REGNUM_GENERIC_SP    , LLDB_INVALID_REGNUM, gpr_esp      },      NULL,              NULL},
    { DEFINE_GPR(ss     , NULL)     , { LLDB_INVALID_REGNUM , LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM      , LLDB_INVALID_REGNUM, gpr_ss       },      NULL,              NULL},
    { DEFINE_GPR(eflags , "flags")  , { ehframe_eflags     , dwarf_eflags       , LLDB_REGNUM_GENERIC_FLAGS , LLDB_INVALID_REGNUM, gpr_eflags   },      NULL,              NULL},
    { DEFINE_GPR(eip    , "pc")     , { ehframe_eip        , dwarf_eip          , LLDB_REGNUM_GENERIC_PC    , LLDB_INVALID_REGNUM, gpr_eip      },      NULL,              NULL},
    { DEFINE_GPR(cs     , NULL)     , { LLDB_INVALID_REGNUM , LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM      , LLDB_INVALID_REGNUM, gpr_cs       },      NULL,              NULL},
    { DEFINE_GPR(ds     , NULL)     , { LLDB_INVALID_REGNUM , LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM      , LLDB_INVALID_REGNUM, gpr_ds       },      NULL,              NULL},
    { DEFINE_GPR(es     , NULL)     , { LLDB_INVALID_REGNUM , LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM      , LLDB_INVALID_REGNUM, gpr_es       },      NULL,              NULL},
    { DEFINE_GPR(fs     , NULL)     , { LLDB_INVALID_REGNUM , LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM      , LLDB_INVALID_REGNUM, gpr_fs       },      NULL,              NULL},
    { DEFINE_GPR(gs     , NULL)     , { LLDB_INVALID_REGNUM , LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM      , LLDB_INVALID_REGNUM, gpr_gs       },      NULL,              NULL},

    { DEFINE_FPU_UINT(fcw)          , { LLDB_INVALID_REGNUM , LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM      , LLDB_INVALID_REGNUM, fpu_fcw      },      NULL,              NULL},
    { DEFINE_FPU_UINT(fsw)          , { LLDB_INVALID_REGNUM , LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM      , LLDB_INVALID_REGNUM, fpu_fsw      },      NULL,              NULL},
    { DEFINE_FPU_UINT(ftw)          , { LLDB_INVALID_REGNUM , LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM      , LLDB_INVALID_REGNUM, fpu_ftw      },      NULL,              NULL},
    { DEFINE_FPU_UINT(fop)          , { LLDB_INVALID_REGNUM , LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM      , LLDB_INVALID_REGNUM, fpu_fop      },      NULL,              NULL},
    { DEFINE_FPU_UINT(ip)           , { LLDB_INVALID_REGNUM , LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM      , LLDB_INVALID_REGNUM, fpu_ip       },      NULL,              NULL},
    { DEFINE_FPU_UINT(cs)           , { LLDB_INVALID_REGNUM , LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM      , LLDB_INVALID_REGNUM, fpu_cs       },      NULL,              NULL},
    { DEFINE_FPU_UINT(dp)           , { LLDB_INVALID_REGNUM , LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM      , LLDB_INVALID_REGNUM, fpu_dp       },      NULL,              NULL},
    { DEFINE_FPU_UINT(ds)           , { LLDB_INVALID_REGNUM , LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM      , LLDB_INVALID_REGNUM, fpu_ds       },      NULL,              NULL},
    { DEFINE_FPU_UINT(mxcsr)        , { LLDB_INVALID_REGNUM , LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM      , LLDB_INVALID_REGNUM, fpu_mxcsr    },      NULL,              NULL},
    { DEFINE_FPU_UINT(mxcsrmask)    , { LLDB_INVALID_REGNUM , LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM      , LLDB_INVALID_REGNUM, fpu_mxcsrmask},      NULL,              NULL},
    { DEFINE_FPU_VECT(stmm,0)   },
    { DEFINE_FPU_VECT(stmm,1)   },
    { DEFINE_FPU_VECT(stmm,2)   },
    { DEFINE_FPU_VECT(stmm,3)   },
    { DEFINE_FPU_VECT(stmm,4)   },
    { DEFINE_FPU_VECT(stmm,5)   },
    { DEFINE_FPU_VECT(stmm,6)   },
    { DEFINE_FPU_VECT(stmm,7)   },
    { DEFINE_FPU_VECT(xmm,0)    },
    { DEFINE_FPU_VECT(xmm,1)    },
    { DEFINE_FPU_VECT(xmm,2)    },
    { DEFINE_FPU_VECT(xmm,3)    },
    { DEFINE_FPU_VECT(xmm,4)    },
    { DEFINE_FPU_VECT(xmm,5)    },
    { DEFINE_FPU_VECT(xmm,6)    },
    { DEFINE_FPU_VECT(xmm,7)    },

    { DEFINE_EXC(trapno)            , { LLDB_INVALID_REGNUM , LLDB_INVALID_REGNUM   , LLDB_INVALID_REGNUM   , LLDB_INVALID_REGNUM, exc_trapno },       NULL,              NULL},
    { DEFINE_EXC(err)               , { LLDB_INVALID_REGNUM , LLDB_INVALID_REGNUM   , LLDB_INVALID_REGNUM   , LLDB_INVALID_REGNUM, exc_err },          NULL,              NULL},
    { DEFINE_EXC(faultvaddr)        , { LLDB_INVALID_REGNUM , LLDB_INVALID_REGNUM   , LLDB_INVALID_REGNUM   , LLDB_INVALID_REGNUM, exc_faultvaddr },   NULL,              NULL}
};

static size_t k_num_register_infos = llvm::array_lengthof(g_register_infos);

RegisterContextDarwin_i386::RegisterContextDarwin_i386 (Thread &thread, uint32_t concrete_frame_idx) :
    RegisterContext(thread, concrete_frame_idx),
    gpr(),
    fpu(),
    exc()
{
    uint32_t i;
    for (i=0; i<kNumErrors; i++)
    {
        gpr_errs[i] = -1;
        fpu_errs[i] = -1;
        exc_errs[i] = -1;
    }
}

RegisterContextDarwin_i386::~RegisterContextDarwin_i386()
{
}


void
RegisterContextDarwin_i386::InvalidateAllRegisters ()
{
    InvalidateAllRegisterStates();
}


size_t
RegisterContextDarwin_i386::GetRegisterCount ()
{
    assert(k_num_register_infos == k_num_registers);
    return k_num_registers;
}

const RegisterInfo *
RegisterContextDarwin_i386::GetRegisterInfoAtIndex (size_t reg)
{
    assert(k_num_register_infos == k_num_registers);
    if (reg < k_num_registers)
        return &g_register_infos[reg];
    return NULL;
}

size_t
RegisterContextDarwin_i386::GetRegisterInfosCount ()
{
    return k_num_register_infos;
}

const RegisterInfo *
RegisterContextDarwin_i386::GetRegisterInfos ()
{
    return g_register_infos;
}


// General purpose registers
static uint32_t
g_gpr_regnums[] =
{
    gpr_eax,
    gpr_ebx,
    gpr_ecx,
    gpr_edx,
    gpr_edi,
    gpr_esi,
    gpr_ebp,
    gpr_esp,
    gpr_ss,
    gpr_eflags,
    gpr_eip,
    gpr_cs,
    gpr_ds,
    gpr_es,
    gpr_fs,
    gpr_gs
};

// Floating point registers
static uint32_t
g_fpu_regnums[] =
{
    fpu_fcw,
    fpu_fsw,
    fpu_ftw,
    fpu_fop,
    fpu_ip,
    fpu_cs,
    fpu_dp,
    fpu_ds,
    fpu_mxcsr,
    fpu_mxcsrmask,
    fpu_stmm0,
    fpu_stmm1,
    fpu_stmm2,
    fpu_stmm3,
    fpu_stmm4,
    fpu_stmm5,
    fpu_stmm6,
    fpu_stmm7,
    fpu_xmm0,
    fpu_xmm1,
    fpu_xmm2,
    fpu_xmm3,
    fpu_xmm4,
    fpu_xmm5,
    fpu_xmm6,
    fpu_xmm7
};

// Exception registers

static uint32_t
g_exc_regnums[] =
{
    exc_trapno,
    exc_err,
    exc_faultvaddr
};

// Number of registers in each register set
const size_t k_num_gpr_registers = llvm::array_lengthof(g_gpr_regnums);
const size_t k_num_fpu_registers = llvm::array_lengthof(g_fpu_regnums);
const size_t k_num_exc_registers = llvm::array_lengthof(g_exc_regnums);

//----------------------------------------------------------------------
// Register set definitions. The first definitions at register set index
// of zero is for all registers, followed by other registers sets. The
// register information for the all register set need not be filled in.
//----------------------------------------------------------------------
static const RegisterSet g_reg_sets[] =
{
    { "General Purpose Registers",  "gpr",  k_num_gpr_registers,    g_gpr_regnums,      },
    { "Floating Point Registers",   "fpu",  k_num_fpu_registers,    g_fpu_regnums       },
    { "Exception State Registers",  "exc",  k_num_exc_registers,    g_exc_regnums       }
};

const size_t k_num_regsets = llvm::array_lengthof(g_reg_sets);


size_t
RegisterContextDarwin_i386::GetRegisterSetCount ()
{
    return k_num_regsets;
}

const RegisterSet *
RegisterContextDarwin_i386::GetRegisterSet (size_t reg_set)
{
    if (reg_set < k_num_regsets)
        return &g_reg_sets[reg_set];
    return NULL;
}


//----------------------------------------------------------------------
// Register information definitions for 32 bit i386.
//----------------------------------------------------------------------
int
RegisterContextDarwin_i386::GetSetForNativeRegNum (int reg_num)
{
    if (reg_num < fpu_fcw)
        return GPRRegSet;
    else if (reg_num < exc_trapno)
        return FPURegSet;
    else if (reg_num < k_num_registers)
        return EXCRegSet;
    return -1;
}


void
RegisterContextDarwin_i386::LogGPR(Log *log, const char *title)
{
    if (log)
    {
        if (title)
            log->Printf ("%s", title);
        for (uint32_t i=0; i<k_num_gpr_registers; i++)
        {
            uint32_t reg = gpr_eax + i;
            log->Printf("%12s = 0x%8.8x", g_register_infos[reg].name, (&gpr.eax)[reg]);
        }
    }
}



int
RegisterContextDarwin_i386::ReadGPR (bool force)
{
    int set = GPRRegSet;
    if (force || !RegisterSetIsCached(set))
    {
        SetError(set, Read, DoReadGPR(GetThreadID(), set, gpr));
    }
    return GetError(set, Read);
}

int
RegisterContextDarwin_i386::ReadFPU (bool force)
{
    int set = FPURegSet;
    if (force || !RegisterSetIsCached(set))
    {
        SetError(set, Read, DoReadFPU(GetThreadID(), set, fpu));
    }
    return GetError(set, Read);
}

int
RegisterContextDarwin_i386::ReadEXC (bool force)
{
    int set = EXCRegSet;
    if (force || !RegisterSetIsCached(set))
    {
        SetError(set, Read, DoReadEXC(GetThreadID(), set, exc));
    }
    return GetError(set, Read);
}

int
RegisterContextDarwin_i386::WriteGPR ()
{
    int set = GPRRegSet;
    if (!RegisterSetIsCached(set))
    {
        SetError (set, Write, -1);
        return -1;
    }
    SetError (set, Write, DoWriteGPR(GetThreadID(), set, gpr));
    SetError (set, Read, -1);
    return GetError(set, Write);
}

int
RegisterContextDarwin_i386::WriteFPU ()
{
    int set = FPURegSet;
    if (!RegisterSetIsCached(set))
    {
        SetError (set, Write, -1);
        return -1;
    }
    SetError (set, Write, DoWriteFPU(GetThreadID(), set, fpu));
    SetError (set, Read, -1);
    return GetError(set, Write);
}

int
RegisterContextDarwin_i386::WriteEXC ()
{
    int set = EXCRegSet;
    if (!RegisterSetIsCached(set))
    {
        SetError (set, Write, -1);
        return -1;
    }
    SetError (set, Write, DoWriteEXC(GetThreadID(), set, exc));
    SetError (set, Read, -1);
    return GetError(set, Write);
}

int
RegisterContextDarwin_i386::ReadRegisterSet (uint32_t set, bool force)
{
    switch (set)
    {
    case GPRRegSet:    return ReadGPR(force);
    case FPURegSet:    return ReadFPU(force);
    case EXCRegSet:    return ReadEXC(force);
    default: break;
    }
    return -1;
}

int
RegisterContextDarwin_i386::WriteRegisterSet (uint32_t set)
{
    // Make sure we have a valid context to set.
    if (RegisterSetIsCached(set))
    {
        switch (set)
        {
        case GPRRegSet:    return WriteGPR();
        case FPURegSet:    return WriteFPU();
        case EXCRegSet:    return WriteEXC();
        default: break;
        }
    }
    return -1;
}

bool
RegisterContextDarwin_i386::ReadRegister (const RegisterInfo *reg_info,
                                        RegisterValue &value)
{
    const uint32_t reg = reg_info->kinds[eRegisterKindLLDB];
    int set = RegisterContextDarwin_i386::GetSetForNativeRegNum (reg);

    if (set == -1)
        return false;

    if (ReadRegisterSet(set, false) != 0)
        return false;

    switch (reg)
    {
    case gpr_eax:
    case gpr_ebx:
    case gpr_ecx:
    case gpr_edx:
    case gpr_edi:
    case gpr_esi:
    case gpr_ebp:
    case gpr_esp:
    case gpr_ss:
    case gpr_eflags:
    case gpr_eip:
    case gpr_cs:
    case gpr_ds:
    case gpr_es:
    case gpr_fs:
    case gpr_gs:
        value = (&gpr.eax)[reg - gpr_eax];
        break;

    case fpu_fcw:
        value = fpu.fcw;
        break;

    case fpu_fsw:
        value = fpu.fsw;
        break;

    case fpu_ftw:
        value  = fpu.ftw;
        break;

    case fpu_fop:
        value = fpu.fop;
        break;

    case fpu_ip:
        value = fpu.ip;
        break;

    case fpu_cs:
        value = fpu.cs;
        break;

    case fpu_dp:
        value = fpu.dp;
        break;

    case fpu_ds:
        value = fpu.ds;
        break;

    case fpu_mxcsr:
        value = fpu.mxcsr;
        break;

    case fpu_mxcsrmask:
        value = fpu.mxcsrmask;
        break;

    case fpu_stmm0:
    case fpu_stmm1:
    case fpu_stmm2:
    case fpu_stmm3:
    case fpu_stmm4:
    case fpu_stmm5:
    case fpu_stmm6:
    case fpu_stmm7:
        // These values don't fit into scalar types,
        // RegisterContext::ReadRegisterBytes() must be used for these
        // registers
        //::memcpy (reg_value.value.vector.uint8, fpu.stmm[reg - fpu_stmm0].bytes, 10);
        return false;

    case fpu_xmm0:
    case fpu_xmm1:
    case fpu_xmm2:
    case fpu_xmm3:
    case fpu_xmm4:
    case fpu_xmm5:
    case fpu_xmm6:
    case fpu_xmm7:
        // These values don't fit into scalar types, RegisterContext::ReadRegisterBytes()
        // must be used for these registers
        //::memcpy (reg_value.value.vector.uint8, fpu.xmm[reg - fpu_xmm0].bytes, 16);
        return false;

    case exc_trapno:
        value = exc.trapno;
        break;

    case exc_err:
        value = exc.err;
        break;

    case exc_faultvaddr:
        value = exc.faultvaddr;
        break;

    default:
        return false;
    }
    return true;
}


bool
RegisterContextDarwin_i386::WriteRegister (const RegisterInfo *reg_info,
                                         const RegisterValue &value)
{
    const uint32_t reg = reg_info->kinds[eRegisterKindLLDB];
    int set = GetSetForNativeRegNum (reg);

    if (set == -1)
        return false;

    if (ReadRegisterSet(set, false) != 0)
        return false;

    switch (reg)
    {
    case gpr_eax:
    case gpr_ebx:
    case gpr_ecx:
    case gpr_edx:
    case gpr_edi:
    case gpr_esi:
    case gpr_ebp:
    case gpr_esp:
    case gpr_ss:
    case gpr_eflags:
    case gpr_eip:
    case gpr_cs:
    case gpr_ds:
    case gpr_es:
    case gpr_fs:
    case gpr_gs:
        (&gpr.eax)[reg - gpr_eax] = value.GetAsUInt32();
        break;

    case fpu_fcw:
        fpu.fcw = value.GetAsUInt16();
        break;

    case fpu_fsw:
        fpu.fsw = value.GetAsUInt16();
        break;

    case fpu_ftw:
        fpu.ftw = value.GetAsUInt8();
        break;

    case fpu_fop:
        fpu.fop = value.GetAsUInt16();
        break;

    case fpu_ip:
        fpu.ip = value.GetAsUInt32();
        break;

    case fpu_cs:
        fpu.cs = value.GetAsUInt16();
        break;

    case fpu_dp:
        fpu.dp = value.GetAsUInt32();
        break;

    case fpu_ds:
        fpu.ds = value.GetAsUInt16();
        break;

    case fpu_mxcsr:
        fpu.mxcsr = value.GetAsUInt32();
        break;

    case fpu_mxcsrmask:
        fpu.mxcsrmask = value.GetAsUInt32();
        break;

    case fpu_stmm0:
    case fpu_stmm1:
    case fpu_stmm2:
    case fpu_stmm3:
    case fpu_stmm4:
    case fpu_stmm5:
    case fpu_stmm6:
    case fpu_stmm7:
        // These values don't fit into scalar types, RegisterContext::ReadRegisterBytes()
        // must be used for these registers
        ::memcpy (fpu.stmm[reg - fpu_stmm0].bytes, value.GetBytes(), value.GetByteSize());
        return false;

    case fpu_xmm0:
    case fpu_xmm1:
    case fpu_xmm2:
    case fpu_xmm3:
    case fpu_xmm4:
    case fpu_xmm5:
    case fpu_xmm6:
    case fpu_xmm7:
        // These values don't fit into scalar types, RegisterContext::ReadRegisterBytes()
        // must be used for these registers
        ::memcpy (fpu.xmm[reg - fpu_xmm0].bytes, value.GetBytes(), value.GetByteSize());
        return false;

    case exc_trapno:
        exc.trapno = value.GetAsUInt32();
        break;

    case exc_err:
        exc.err = value.GetAsUInt32();
        break;

    case exc_faultvaddr:
        exc.faultvaddr = value.GetAsUInt32();
        break;

    default:
        return false;
    }
    return WriteRegisterSet(set) == 0;
}

bool
RegisterContextDarwin_i386::ReadAllRegisterValues (lldb::DataBufferSP &data_sp)
{
    data_sp.reset (new DataBufferHeap (REG_CONTEXT_SIZE, 0));
    if (data_sp &&
        ReadGPR (false) == 0 &&
        ReadFPU (false) == 0 &&
        ReadEXC (false) == 0)
    {
        uint8_t *dst = data_sp->GetBytes();
        ::memcpy (dst, &gpr, sizeof(gpr));
        dst += sizeof(gpr);

        ::memcpy (dst, &fpu, sizeof(fpu));
        dst += sizeof(gpr);

        ::memcpy (dst, &exc, sizeof(exc));
        return true;
    }
    return false;
}

bool
RegisterContextDarwin_i386::WriteAllRegisterValues (const lldb::DataBufferSP &data_sp)
{
    if (data_sp && data_sp->GetByteSize() == REG_CONTEXT_SIZE)
    {
        const uint8_t *src = data_sp->GetBytes();
        ::memcpy (&gpr, src, sizeof(gpr));
        src += sizeof(gpr);

        ::memcpy (&fpu, src, sizeof(fpu));
        src += sizeof(gpr);

        ::memcpy (&exc, src, sizeof(exc));
        uint32_t success_count = 0;
        if (WriteGPR() == 0)
            ++success_count;
        if (WriteFPU() == 0)
            ++success_count;
        if (WriteEXC() == 0)
            ++success_count;
        return success_count == 3;
    }
    return false;
}


uint32_t
RegisterContextDarwin_i386::ConvertRegisterKindToRegisterNumber (lldb::RegisterKind kind, uint32_t reg)
{
    if (kind == eRegisterKindGeneric)
    {
        switch (reg)
        {
        case LLDB_REGNUM_GENERIC_PC:        return gpr_eip;
        case LLDB_REGNUM_GENERIC_SP:        return gpr_esp;
        case LLDB_REGNUM_GENERIC_FP:        return gpr_ebp;
        case LLDB_REGNUM_GENERIC_FLAGS:     return gpr_eflags;
        case LLDB_REGNUM_GENERIC_RA:
        default:
            break;
        }
    }
    else if (kind == eRegisterKindEHFrame || kind == eRegisterKindDWARF)
    {
        switch (reg)
        {
        case dwarf_eax:     return gpr_eax;
        case dwarf_ecx:     return gpr_ecx;
        case dwarf_edx:     return gpr_edx;
        case dwarf_ebx:     return gpr_ebx;
        case dwarf_esp:     return gpr_esp;
        case dwarf_ebp:     return gpr_ebp;
        case dwarf_esi:     return gpr_esi;
        case dwarf_edi:     return gpr_edi;
        case dwarf_eip:     return gpr_eip;
        case dwarf_eflags:  return gpr_eflags;
        case dwarf_stmm0:   return fpu_stmm0;
        case dwarf_stmm1:   return fpu_stmm1;
        case dwarf_stmm2:   return fpu_stmm2;
        case dwarf_stmm3:   return fpu_stmm3;
        case dwarf_stmm4:   return fpu_stmm4;
        case dwarf_stmm5:   return fpu_stmm5;
        case dwarf_stmm6:   return fpu_stmm6;
        case dwarf_stmm7:   return fpu_stmm7;
        case dwarf_xmm0:    return fpu_xmm0;
        case dwarf_xmm1:    return fpu_xmm1;
        case dwarf_xmm2:    return fpu_xmm2;
        case dwarf_xmm3:    return fpu_xmm3;
        case dwarf_xmm4:    return fpu_xmm4;
        case dwarf_xmm5:    return fpu_xmm5;
        case dwarf_xmm6:    return fpu_xmm6;
        case dwarf_xmm7:    return fpu_xmm7;
        default:
            break;
        }
    }
    else if (kind == eRegisterKindLLDB)
    {
        return reg;
    }
    return LLDB_INVALID_REGNUM;
}


bool
RegisterContextDarwin_i386::HardwareSingleStep (bool enable)
{
    if (ReadGPR(false) != 0)
        return false;

    const uint32_t trace_bit = 0x100u;
    if (enable)
    {
        // If the trace bit is already set, there is nothing to do
        if (gpr.eflags & trace_bit)
            return true;
        else
            gpr.eflags |= trace_bit;
    }
    else
    {
        // If the trace bit is already cleared, there is nothing to do
        if (gpr.eflags & trace_bit)
            gpr.eflags &= ~trace_bit;
        else
            return true;
    }

    return WriteGPR() == 0;
}



