Add register context for i386 on Linux.

Patch by Marco Minutoli!

llvm-svn: 126696

3 files changed, 791 insertions, 4 deletions

diff --git a/lldb/source/Plugins/Process/Linux/LinuxThread.cpp b/lldb/source/Plugins/Process/Linux/LinuxThread.cpp
index 397d31bf497..ebda0d8965c 100644
--- a/lldb/source/Plugins/Process/Linux/LinuxThread.cpp
+++ b/lldb/source/Plugins/Process/Linux/LinuxThread.cpp
@@ -12,6 +12,7 @@
 
 // C++ Includes
 // Other libraries and framework includes
+#include "lldb/Host/Host.h"
 #include "lldb/Target/Process.h"
 #include "lldb/Target/StopInfo.h"
 #include "lldb/Target/Target.h"
@@ -19,6 +20,7 @@
 #include "LinuxThread.h"
 #include "ProcessLinux.h"
 #include "ProcessMonitor.h"
+#include "RegisterContextLinux_i386.h"
 #include "RegisterContextLinux_x86_64.h"
 #include "UnwindLLDB.h"
 
@@ -59,11 +61,9 @@ LinuxThread::GetInfo()
 lldb::RegisterContextSP
 LinuxThread::GetRegisterContext()
 {
-    ProcessLinux &process = static_cast<ProcessLinux&>(GetProcess());
-
     if (!m_reg_context_sp)
     {
-        ArchSpec arch = process.GetTarget().GetArchitecture();
+        ArchSpec arch = Host::GetArchitecture();
 
         switch (arch.GetCore())
         {
@@ -71,6 +71,12 @@ LinuxThread::GetRegisterContext()
             assert(false && "CPU type not supported!");
             break;
 
+        case ArchSpec::eCore_x86_32_i386:
+        case ArchSpec::eCore_x86_32_i486:
+        case ArchSpec::eCore_x86_32_i486sx:
+            m_reg_context_sp.reset(new RegisterContextLinux_i386(*this, 0));
+            break;
+
         case ArchSpec::eCore_x86_64_x86_64:
             m_reg_context_sp.reset(new RegisterContextLinux_x86_64(*this, 0));
             break;
@@ -99,7 +105,7 @@ LinuxThread::CreateRegisterContextForFrame(lldb_private::StackFrame *frame)
 
     if (frame)
         concrete_frame_idx = frame->GetConcreteFrameIndex();
-        
+
     if (concrete_frame_idx == 0)
         reg_ctx_sp = GetRegisterContext();
     else
diff --git a/lldb/source/Plugins/Process/Linux/RegisterContextLinux_i386.cpp b/lldb/source/Plugins/Process/Linux/RegisterContextLinux_i386.cpp
new file mode 100644
index 00000000000..6bee0c90906
--- /dev/null
+++ b/lldb/source/Plugins/Process/Linux/RegisterContextLinux_i386.cpp
@@ -0,0 +1,633 @@
+//===-- RegisterContextLinux_i386.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/Core/DataExtractor.h"
+#include "lldb/Target/Thread.h"
+#include "lldb/Host/Endian.h"
+
+#include "ProcessLinux.h"
+#include "ProcessMonitor.h"
+#include "RegisterContextLinux_i386.h"
+
+using namespace lldb_private;
+using namespace lldb;
+
+enum
+{
+    k_first_gpr,
+    gpr_eax = k_first_gpr,
+    gpr_ebx,
+    gpr_ecx,
+    gpr_edx,
+    gpr_edi,
+    gpr_esi,
+    gpr_ebp,
+    gpr_esp,
+    gpr_ss,
+    gpr_eflags,
+    gpr_orig_ax,
+    gpr_eip,
+    gpr_cs,
+    gpr_ds,
+    gpr_es,
+    gpr_fs,
+    gpr_gs,
+    k_last_gpr = gpr_gs,
+
+    k_first_fpr,
+    fpu_fcw = k_first_fpr,
+    fpu_fsw,
+    fpu_ftw,
+    fpu_fop,
+    fpu_ip,
+    fpu_cs,
+    fpu_foo,
+    fpu_fos,
+    fpu_mxcsr,
+    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,
+    k_last_fpr = fpu_xmm7,
+
+    k_num_registers,
+    k_num_gpr_registers = k_last_gpr - k_first_gpr + 1,
+    k_num_fpu_registers = k_last_fpr - k_first_fpr + 1
+};
+
+// Number of register sets provided by this context.
+enum
+{
+    k_num_register_sets = 2
+};
+
+enum
+{
+    gcc_eax = 0,
+    gcc_ecx,
+    gcc_edx,
+    gcc_ebx,
+    gcc_ebp,
+    gcc_esp,
+    gcc_esi,
+    gcc_edi,
+    gcc_eip,
+    gcc_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
+};
+
+enum
+{
+    gdb_eax        =  0,
+    gdb_ecx        =  1,
+    gdb_edx        =  2,
+    gdb_ebx        =  3,
+    gdb_esp        =  4,
+    gdb_ebp        =  5,
+    gdb_esi        =  6,
+    gdb_edi        =  7,
+    gdb_eip        =  8,
+    gdb_eflags     =  9,
+    gdb_cs         = 10,
+    gdb_ss         = 11,
+    gdb_ds         = 12,
+    gdb_es         = 13,
+    gdb_fs         = 14,
+    gdb_gs         = 15,
+    gdb_stmm0      = 16,
+    gdb_stmm1      = 17,
+    gdb_stmm2      = 18,
+    gdb_stmm3      = 19,
+    gdb_stmm4      = 20,
+    gdb_stmm5      = 21,
+    gdb_stmm6      = 22,
+    gdb_stmm7      = 23,
+    gdb_fcw        = 24,
+    gdb_fsw        = 25,
+    gdb_ftw        = 26,
+    gdb_fpu_cs     = 27,
+    gdb_ip         = 28,
+    gdb_fpu_ds     = 29,
+    gdb_dp         = 30,
+    gdb_fop        = 31,
+    gdb_xmm0       = 32,
+    gdb_xmm1       = 33,
+    gdb_xmm2       = 34,
+    gdb_xmm3       = 35,
+    gdb_xmm4       = 36,
+    gdb_xmm5       = 37,
+    gdb_xmm6       = 38,
+    gdb_xmm7       = 39,
+    gdb_mxcsr      = 40,
+    gdb_mm0        = 41,
+    gdb_mm1        = 42,
+    gdb_mm2        = 43,
+    gdb_mm3        = 44,
+    gdb_mm4        = 45,
+    gdb_mm5        = 46,
+    gdb_mm6        = 47,
+    gdb_mm7        = 48
+};
+
+static const
+uint32_t g_gpr_regnums[k_num_gpr_registers] =
+{
+    gpr_eax,
+    gpr_ebx,
+    gpr_ecx,
+    gpr_edx,
+    gpr_edi,
+    gpr_esi,
+    gpr_ebp,
+    gpr_esp,
+    gpr_ss,
+    gpr_eflags,
+    gpr_orig_ax,
+    gpr_eip,
+    gpr_cs,
+    gpr_ds,
+    gpr_es,
+    gpr_fs,
+    gpr_gs,
+};
+
+static const uint32_t
+g_fpu_regnums[k_num_fpu_registers] =
+{
+    fpu_fcw,
+    fpu_fsw,
+    fpu_ftw,
+    fpu_fop,
+    fpu_ip,
+    fpu_cs,
+    fpu_foo,
+    fpu_fos,
+    fpu_mxcsr,
+    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,
+};
+
+static const RegisterSet
+g_reg_sets[k_num_register_sets] =
+{
+    { "General Purpose Registers", "gpr", k_num_gpr_registers, g_gpr_regnums },
+    { "Floating Point Registers",  "fpu", k_num_fpu_registers, g_fpu_regnums }
+};
+
+// Computes the offset of the given GPR in the user data area.
+#define GPR_OFFSET(regname) \
+    (offsetof(RegisterContextLinux_i386::UserArea, regs) + \
+     offsetof(RegisterContextLinux_i386::GPR, regname))
+
+// Computes the offset of the given FPR in the user data area.
+#define FPR_OFFSET(regname) \
+    (offsetof(RegisterContextLinux_i386::UserArea, i387) + \
+     offsetof(RegisterContextLinux_i386::FPU, regname))
+
+// Number of bytes needed to represent a GPR.
+#define GPR_SIZE(reg) sizeof(((RegisterContextLinux_i386::GPR*)NULL)->reg)
+
+// Number of bytes needed to represent a FPR.
+#define FPR_SIZE(reg) sizeof(((RegisterContextLinux_i386::FPU*)NULL)->reg)
+
+// Number of bytes needed to represent the i'th FP register.
+#define FP_SIZE sizeof(((RegisterContextLinux_i386::MMSReg*)NULL)->bytes)
+
+// Number of bytes needed to represent an XMM register.
+#define XMM_SIZE sizeof(RegisterContextLinux_i386::XMMReg)
+
+#define DEFINE_GPR(reg, alt, kind1, kind2, kind3, kind4)        \
+    { #reg, alt, GPR_SIZE(reg), GPR_OFFSET(reg), eEncodingUint, \
+      eFormatHex, { kind1, kind2, kind3, kind4, gpr_##reg } }
+
+#define DEFINE_FPR(reg, kind1, kind2, kind3, kind4)              \
+    { #reg, NULL, FPR_SIZE(reg), FPR_OFFSET(reg), eEncodingUint, \
+      eFormatHex, { kind1, kind2, kind3, kind4, fpu_##reg } }
+
+#define DEFINE_FP(reg, i)                                          \
+    { #reg#i, NULL, FP_SIZE, FPR_OFFSET(reg[i]), eEncodingVector,  \
+      eFormatVectorOfUInt8,                                        \
+      { dwarf_##reg##i, dwarf_##reg##i,                            \
+        LLDB_INVALID_REGNUM, gdb_##reg##i, fpu_##reg##i } }
+
+#define DEFINE_XMM(reg, i)                                         \
+    { #reg#i, NULL, XMM_SIZE, FPR_OFFSET(reg[i]), eEncodingVector, \
+      eFormatVectorOfUInt8,                                        \
+      { dwarf_##reg##i, dwarf_##reg##i,                            \
+        LLDB_INVALID_REGNUM, gdb_##reg##i, fpu_##reg##i } }
+
+static RegisterInfo
+g_register_infos[k_num_registers] =
+{
+    // General purpose registers.
+    DEFINE_GPR(eax,    NULL,    gcc_eax,    dwarf_eax,    LLDB_INVALID_REGNUM,    gdb_eax),
+    DEFINE_GPR(ebx,    NULL,    gcc_ebx,    dwarf_ebx,    LLDB_INVALID_REGNUM,    gdb_ebx),
+    DEFINE_GPR(ecx,    NULL,    gcc_ecx,    dwarf_ecx,    LLDB_INVALID_REGNUM,    gdb_ecx),
+    DEFINE_GPR(edx,    NULL,    gcc_edx,    dwarf_edx,    LLDB_INVALID_REGNUM,    gdb_edx),
+    DEFINE_GPR(edi,    NULL,    gcc_edi,    dwarf_edi,    LLDB_INVALID_REGNUM,    gdb_edi),
+    DEFINE_GPR(esi,    NULL,    gcc_esi,    dwarf_esi,    LLDB_INVALID_REGNUM,    gdb_esi),
+    DEFINE_GPR(ebp,    "fp",    gcc_ebp,    dwarf_ebp,    LLDB_INVALID_REGNUM,    gdb_ebp),
+    DEFINE_GPR(esp,    "sp",    gcc_esp,    dwarf_esp,    LLDB_INVALID_REGNUM,    gdb_esp),
+    DEFINE_GPR(ss,     NULL,    LLDB_INVALID_REGNUM,     LLDB_INVALID_REGNUM,     LLDB_INVALID_REGNUM,    gdb_ss),
+    DEFINE_GPR(eflags, "flags", gcc_eflags, dwarf_eflags, LLDB_INVALID_REGNUM,    gdb_eflags),
+    DEFINE_GPR(eip,    "pc",    gcc_eip,    dwarf_eip,    LLDB_INVALID_REGNUM,    gdb_eip),
+    DEFINE_GPR(cs,     NULL,    LLDB_INVALID_REGNUM,     LLDB_INVALID_REGNUM,     LLDB_INVALID_REGNUM,    gdb_cs),
+    DEFINE_GPR(ds,     NULL,    LLDB_INVALID_REGNUM,     LLDB_INVALID_REGNUM,     LLDB_INVALID_REGNUM,    gdb_ds),
+    DEFINE_GPR(es,     NULL,    LLDB_INVALID_REGNUM,     LLDB_INVALID_REGNUM,     LLDB_INVALID_REGNUM,    gdb_es),
+    DEFINE_GPR(fs,     NULL,    LLDB_INVALID_REGNUM,     LLDB_INVALID_REGNUM,     LLDB_INVALID_REGNUM,    gdb_fs),
+    DEFINE_GPR(gs,     NULL,    LLDB_INVALID_REGNUM,     LLDB_INVALID_REGNUM,     LLDB_INVALID_REGNUM,    gdb_gs),
+
+    // Floating point registers.
+    DEFINE_FPR(fcw,       LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, gdb_fcw),
+    DEFINE_FPR(fsw,       LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, gdb_fsw),
+    DEFINE_FPR(ftw,       LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, gdb_ftw),
+    DEFINE_FPR(fop,       LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, gdb_fop),
+    DEFINE_FPR(ip,        LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, gdb_ip),
+    DEFINE_FPR(cs,        LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, gdb_fpu_cs),
+    DEFINE_FPR(foo,       LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, gdb_dp),
+    DEFINE_FPR(fos,       LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, gdb_fpu_ds),
+    DEFINE_FPR(mxcsr,     LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, gdb_mxcsr),
+
+    DEFINE_FP(stmm, 0),
+    DEFINE_FP(stmm, 1),
+    DEFINE_FP(stmm, 2),
+    DEFINE_FP(stmm, 3),
+    DEFINE_FP(stmm, 4),
+    DEFINE_FP(stmm, 5),
+    DEFINE_FP(stmm, 6),
+    DEFINE_FP(stmm, 7),
+
+    // XMM registers
+    DEFINE_XMM(xmm, 0),
+    DEFINE_XMM(xmm, 1),
+    DEFINE_XMM(xmm, 2),
+    DEFINE_XMM(xmm, 3),
+    DEFINE_XMM(xmm, 4),
+    DEFINE_XMM(xmm, 5),
+    DEFINE_XMM(xmm, 6),
+    DEFINE_XMM(xmm, 7),
+
+};
+
+static unsigned GetRegOffset(unsigned reg)
+{
+    assert(reg < k_num_registers && "Invalid register number.");
+    return g_register_infos[reg].byte_offset;
+}
+
+static unsigned GetRegSize(unsigned reg)
+{
+    assert(reg < k_num_registers && "Invalid register number.");
+    return g_register_infos[reg].byte_size;
+}
+
+static bool IsGPR(unsigned reg)
+{
+    return reg <= k_last_gpr;   // GPR's come first.
+}
+
+static bool IsFPR(unsigned reg)
+{
+    return (k_first_fpr <= reg && reg <= k_last_fpr);
+}
+
+
+RegisterContextLinux_i386::RegisterContextLinux_i386(Thread &thread,
+                                                     uint32_t concrete_frame_idx)
+    : RegisterContextLinux(thread, concrete_frame_idx)
+{
+}
+
+RegisterContextLinux_i386::~RegisterContextLinux_i386()
+{
+}
+
+ProcessMonitor &
+RegisterContextLinux_i386::GetMonitor()
+{
+    ProcessLinux *process = static_cast<ProcessLinux*>(CalculateProcess());
+    return process->GetMonitor();
+}
+
+void
+RegisterContextLinux_i386::Invalidate()
+{
+}
+
+void
+RegisterContextLinux_i386::InvalidateAllRegisters()
+{
+}
+
+size_t
+RegisterContextLinux_i386::GetRegisterCount()
+{
+    return k_num_registers;
+}
+
+const RegisterInfo *
+RegisterContextLinux_i386::GetRegisterInfoAtIndex(uint32_t reg)
+{
+    if (reg < k_num_registers)
+        return &g_register_infos[reg];
+    else
+        return NULL;
+}
+
+size_t
+RegisterContextLinux_i386::GetRegisterSetCount()
+{
+    return k_num_register_sets;
+}
+
+const RegisterSet *
+RegisterContextLinux_i386::GetRegisterSet(uint32_t set)
+{
+    if (set < k_num_register_sets)
+        return &g_reg_sets[set];
+    else
+        return NULL;
+}
+
+bool
+RegisterContextLinux_i386::ReadRegisterValue(uint32_t reg,
+                                               Scalar &value)
+{
+    ProcessMonitor &monitor = GetMonitor();
+    return monitor.ReadRegisterValue(GetRegOffset(reg), value);
+}
+
+bool
+RegisterContextLinux_i386::ReadRegisterBytes(uint32_t reg,
+                                             DataExtractor &data)
+{
+    uint8_t *buf = reinterpret_cast<uint8_t*>(&user);
+    bool status;
+
+    if (IsGPR(reg))
+        status = ReadGPR();
+    else if (IsFPR(reg))
+        status = ReadFPR();
+    else
+    {
+        assert(false && "invalid register number");
+        status = false;
+    }
+
+    if (status)
+        data.SetData(buf + GetRegOffset(reg), GetRegSize(reg), lldb::endian::InlHostByteOrder());
+
+    return status;
+}
+
+bool
+RegisterContextLinux_i386::ReadAllRegisterValues(DataBufferSP &data_sp)
+{
+    return false;
+}
+
+bool
+RegisterContextLinux_i386::WriteRegisterValue(uint32_t reg,
+                                              const Scalar &value)
+{
+    ProcessMonitor &monitor = GetMonitor();
+    return monitor.WriteRegisterValue(GetRegOffset(reg), value);
+}
+
+bool
+RegisterContextLinux_i386::WriteRegisterBytes(uint32_t reg,
+                                              DataExtractor &data,
+                                              uint32_t data_offset)
+{
+    return false;
+}
+
+bool
+RegisterContextLinux_i386::WriteAllRegisterValues(const DataBufferSP &data)
+{
+    return false;
+}
+
+bool
+RegisterContextLinux_i386::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;
+}
+
+uint32_t
+RegisterContextLinux_i386::ConvertRegisterKindToRegisterNumber(uint32_t kind,
+                                                               uint32_t num)
+{
+    if (kind == eRegisterKindGeneric)
+    {
+        switch (num)
+        {
+        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:
+            return LLDB_INVALID_REGNUM;
+        }
+    }
+
+    if (kind == eRegisterKindGCC || kind == eRegisterKindDWARF)
+    {
+        switch (num)
+        {
+        case dwarf_eax:  return gpr_eax;
+        case dwarf_edx:  return gpr_edx;
+        case dwarf_ecx:  return gpr_ecx;
+        case dwarf_ebx:  return gpr_ebx;
+        case dwarf_esi:  return gpr_esi;
+        case dwarf_edi:  return gpr_edi;
+        case dwarf_ebp:  return gpr_ebp;
+        case dwarf_esp:  return gpr_esp;
+        case dwarf_eip:  return gpr_eip;
+        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;
+        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;
+        default:
+            return LLDB_INVALID_REGNUM;
+        }
+    }
+
+    if (kind == eRegisterKindGDB)
+    {
+        switch (num)
+        {
+        case gdb_eax     : return gpr_eax;
+        case gdb_ebx     : return gpr_ebx;
+        case gdb_ecx     : return gpr_ecx;
+        case gdb_edx     : return gpr_edx;
+        case gdb_esi     : return gpr_esi;
+        case gdb_edi     : return gpr_edi;
+        case gdb_ebp     : return gpr_ebp;
+        case gdb_esp     : return gpr_esp;
+        case gdb_eip     : return gpr_eip;
+        case gdb_eflags  : return gpr_eflags;
+        case gdb_cs      : return gpr_cs;
+        case gdb_ss      : return gpr_ss;
+        case gdb_ds      : return gpr_ds;
+        case gdb_es      : return gpr_es;
+        case gdb_fs      : return gpr_fs;
+        case gdb_gs      : return gpr_gs;
+        case gdb_stmm0   : return fpu_stmm0;
+        case gdb_stmm1   : return fpu_stmm1;
+        case gdb_stmm2   : return fpu_stmm2;
+        case gdb_stmm3   : return fpu_stmm3;
+        case gdb_stmm4   : return fpu_stmm4;
+        case gdb_stmm5   : return fpu_stmm5;
+        case gdb_stmm6   : return fpu_stmm6;
+        case gdb_stmm7   : return fpu_stmm7;
+        case gdb_fcw     : return fpu_fcw;
+        case gdb_fsw     : return fpu_fsw;
+        case gdb_ftw     : return fpu_ftw;
+        case gdb_fpu_cs  : return fpu_cs;
+        case gdb_ip      : return fpu_ip;
+        case gdb_fpu_ds  : return fpu_fos;
+        case gdb_dp      : return fpu_foo;
+        case gdb_fop     : return fpu_fop;
+        case gdb_xmm0    : return fpu_xmm0;
+        case gdb_xmm1    : return fpu_xmm1;
+        case gdb_xmm2    : return fpu_xmm2;
+        case gdb_xmm3    : return fpu_xmm3;
+        case gdb_xmm4    : return fpu_xmm4;
+        case gdb_xmm5    : return fpu_xmm5;
+        case gdb_xmm6    : return fpu_xmm6;
+        case gdb_xmm7    : return fpu_xmm7;
+        case gdb_mxcsr   : return fpu_mxcsr;
+        default:
+            return LLDB_INVALID_REGNUM;
+        }
+    }
+    else if (kind == eRegisterKindLLDB)
+    {
+        return num;
+    }
+
+    return LLDB_INVALID_REGNUM;
+}
+
+bool
+RegisterContextLinux_i386::HardwareSingleStep(bool enable)
+{
+    enum { TRACE_BIT = 0x100 };
+    uint64_t eflags;
+
+    if ((eflags = ReadRegisterAsUnsigned(gpr_eflags, -1UL)) == -1UL)
+        return false;
+
+    if (enable)
+    {
+        if (eflags & TRACE_BIT)
+            return true;
+
+        eflags |= TRACE_BIT;
+    }
+    else
+    {
+        if (!(eflags & TRACE_BIT))
+            return false;
+
+        eflags &= ~TRACE_BIT;
+    }
+
+    return WriteRegisterFromUnsigned(gpr_eflags, eflags);
+}
+
+bool
+RegisterContextLinux_i386::ReadGPR()
+{
+     ProcessMonitor &monitor = GetMonitor();
+     return monitor.ReadGPR(&user.regs);
+}
+
+bool
+RegisterContextLinux_i386::ReadFPR()
+{
+    ProcessMonitor &monitor = GetMonitor();
+    return monitor.ReadFPR(&user.i387);
+}
diff --git a/lldb/source/Plugins/Process/Linux/RegisterContextLinux_i386.h b/lldb/source/Plugins/Process/Linux/RegisterContextLinux_i386.h
new file mode 100644
index 00000000000..30b3d7073c1
--- /dev/null
+++ b/lldb/source/Plugins/Process/Linux/RegisterContextLinux_i386.h
@@ -0,0 +1,148 @@
+//===-- RegisterContextLinux_i386.h ------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef liblldb_RegisterContextLinux_i386_h_
+#define liblldb_RegisterContextLinux_i386_h_
+
+// C Includes
+// C++ Includes
+// Other libraries and framework includes
+// Project includes
+#include "RegisterContextLinux.h"
+
+class RegisterContextLinux_i386 : public RegisterContextLinux
+{
+public:
+    RegisterContextLinux_i386(lldb_private::Thread &thread,
+                              uint32_t concreate_frame_idx);
+
+    ~RegisterContextLinux_i386();
+
+    void
+    Invalidate();
+
+    void
+    InvalidateAllRegisters();
+
+    size_t
+    GetRegisterCount();
+
+    const lldb::RegisterInfo *
+    GetRegisterInfoAtIndex(uint32_t reg);
+
+    size_t
+    GetRegisterSetCount();
+
+    const lldb::RegisterSet *
+    GetRegisterSet(uint32_t set);
+
+    bool
+    ReadRegisterValue(uint32_t reg, lldb_private::Scalar &value);
+
+    bool
+    ReadRegisterBytes(uint32_t reg, lldb_private::DataExtractor &data);
+
+    bool
+    ReadAllRegisterValues(lldb::DataBufferSP &data_sp);
+
+    bool
+    WriteRegisterValue(uint32_t reg, const lldb_private::Scalar &value);
+
+    bool
+    WriteRegisterBytes(uint32_t reg, lldb_private::DataExtractor &data,
+                       uint32_t data_offset = 0);
+
+    bool
+    WriteAllRegisterValues(const lldb::DataBufferSP &data_sp);
+
+    uint32_t
+    ConvertRegisterKindToRegisterNumber(uint32_t kind, uint32_t num);
+
+    bool
+    HardwareSingleStep(bool enable);
+
+    bool
+    UpdateAfterBreakpoint();
+
+    struct GPR
+    {
+        uint32_t ebx;
+        uint32_t ecx;
+        uint32_t edx;
+        uint32_t esi;
+        uint32_t edi;
+        uint32_t ebp;
+        uint32_t eax;
+        uint32_t ds;
+        uint32_t es;
+        uint32_t fs;
+        uint32_t gs;
+        uint32_t orig_ax;
+        uint32_t eip;
+        uint32_t cs;
+        uint32_t eflags;
+        uint32_t esp;
+        uint32_t ss;
+    };
+
+    struct MMSReg
+    {
+        uint8_t bytes[8];
+    };
+
+    struct XMMReg
+    {
+        uint8_t bytes[16];
+    };
+
+    struct FPU
+    {
+        uint16_t    fcw;
+        uint16_t    fsw;
+        uint16_t    ftw;
+        uint16_t    fop;
+        uint32_t    ip;
+        uint32_t    cs;
+        uint32_t    foo;
+        uint32_t    fos;
+        uint32_t    mxcsr;
+        uint32_t    reserved;
+        MMSReg      stmm[8];
+        XMMReg      xmm[8];
+        uint32_t    pad[56];
+    };
+
+    struct UserArea
+    {
+        GPR      regs;          // General purpose registers.
+        int32_t  fpvalid;       // True if FPU is being used.
+        FPU      i387;          // FPU registers.
+        uint32_t tsize;         // Text segment size.
+        uint32_t dsize;         // Data segment size.
+        uint32_t ssize;         // Stack segment size.
+        uint32_t start_code;    // VM address of text.
+        uint32_t start_stack;   // VM address of stack bottom (top in rsp).
+        int32_t  signal;        // Signal causing core dump.
+        int32_t  reserved;      // Unused.
+        uint32_t ar0;           // Location of GPR's.
+        FPU*     fpstate;       // Location of FPR's.
+        uint32_t magic;         // Identifier for core dumps.
+        char     u_comm[32];    // Command causing core dump.
+        uint32_t u_debugreg[8]; // Debug registers (DR0 - DR7).
+    };
+private:
+    UserArea user;
+
+    ProcessMonitor &GetMonitor();
+
+    bool ReadGPR();
+    bool ReadFPR();
+};
+
+#endif // #ifndef liblldb_RegisterContextLinux_i386_h_