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diff --git a/source/Plugins/Process/FreeBSD/RegisterContextPOSIXProcessMonitor_x86.cpp b/source/Plugins/Process/FreeBSD/RegisterContextPOSIXProcessMonitor_x86.cpp
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index 000000000000..9245441f659f
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+++ b/source/Plugins/Process/FreeBSD/RegisterContextPOSIXProcessMonitor_x86.cpp
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+//===-- RegisterContextPOSIXProcessMonitor_x86.h ---------------*- 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/DataBufferHeap.h"
+#include "lldb/Core/RegisterValue.h"
+#include "lldb/Target/Thread.h"
+
+#include "Plugins/Process/FreeBSD/ProcessPOSIX.h"
+#include "RegisterContextPOSIXProcessMonitor_x86.h"
+#include "Plugins/Process/FreeBSD/ProcessMonitor.h"
+
+using namespace lldb_private;
+using namespace lldb;
+
+// Support ptrace extensions even when compiled without required kernel support
+#ifndef NT_X86_XSTATE
+ #define NT_X86_XSTATE 0x202
+#endif
+
+#define REG_CONTEXT_SIZE (GetGPRSize() + sizeof(FPR))
+
+static uint32_t
+size_and_rw_bits(size_t size, bool read, bool write)
+{
+ uint32_t rw;
+
+ if (read)
+ rw = 0x3; // READ or READ/WRITE
+ else if (write)
+ rw = 0x1; // WRITE
+ else
+ assert(0 && "read and write cannot both be false");
+
+ switch (size)
+ {
+ case 1:
+ return rw;
+ case 2:
+ return (0x1 << 2) | rw;
+ case 4:
+ return (0x3 << 2) | rw;
+ case 8:
+ return (0x2 << 2) | rw;
+ default:
+ assert(0 && "invalid size, must be one of 1, 2, 4, or 8");
+ return 0; // Unreachable. Just to silence compiler.
+ }
+}
+
+RegisterContextPOSIXProcessMonitor_x86_64::RegisterContextPOSIXProcessMonitor_x86_64(Thread &thread,
+ uint32_t concrete_frame_idx,
+ lldb_private::RegisterInfoInterface *register_info)
+ : RegisterContextPOSIX_x86(thread, concrete_frame_idx, register_info)
+{
+}
+
+ProcessMonitor &
+RegisterContextPOSIXProcessMonitor_x86_64::GetMonitor()
+{
+ ProcessSP base = CalculateProcess();
+ ProcessPOSIX *process = static_cast<ProcessPOSIX*>(base.get());
+ return process->GetMonitor();
+}
+
+bool
+RegisterContextPOSIXProcessMonitor_x86_64::ReadGPR()
+{
+ ProcessMonitor &monitor = GetMonitor();
+ return monitor.ReadGPR(m_thread.GetID(), &m_gpr_x86_64, GetGPRSize());
+}
+
+bool
+RegisterContextPOSIXProcessMonitor_x86_64::ReadFPR()
+{
+ ProcessMonitor &monitor = GetMonitor();
+ if (GetFPRType() == eFXSAVE)
+ return monitor.ReadFPR(m_thread.GetID(), &m_fpr.xstate.fxsave, sizeof(m_fpr.xstate.fxsave));
+
+ if (GetFPRType() == eXSAVE)
+ return monitor.ReadRegisterSet(m_thread.GetID(), &m_iovec, sizeof(m_fpr.xstate.xsave), NT_X86_XSTATE);
+ return false;
+}
+
+bool
+RegisterContextPOSIXProcessMonitor_x86_64::WriteGPR()
+{
+ ProcessMonitor &monitor = GetMonitor();
+ return monitor.WriteGPR(m_thread.GetID(), &m_gpr_x86_64, GetGPRSize());
+}
+
+bool
+RegisterContextPOSIXProcessMonitor_x86_64::WriteFPR()
+{
+ ProcessMonitor &monitor = GetMonitor();
+ if (GetFPRType() == eFXSAVE)
+ return monitor.WriteFPR(m_thread.GetID(), &m_fpr.xstate.fxsave, sizeof(m_fpr.xstate.fxsave));
+
+ if (GetFPRType() == eXSAVE)
+ return monitor.WriteRegisterSet(m_thread.GetID(), &m_iovec, sizeof(m_fpr.xstate.xsave), NT_X86_XSTATE);
+ return false;
+}
+
+bool
+RegisterContextPOSIXProcessMonitor_x86_64::ReadRegister(const unsigned reg,
+ RegisterValue &value)
+{
+ ProcessMonitor &monitor = GetMonitor();
+
+#if defined(__FreeBSD__)
+ if (reg >= m_reg_info.first_dr)
+ return monitor.ReadDebugRegisterValue(m_thread.GetID(),
+ GetRegisterOffset(reg),
+ GetRegisterName(reg),
+ GetRegisterSize(reg),
+ value);
+#endif
+ return monitor.ReadRegisterValue(m_thread.GetID(),
+ GetRegisterOffset(reg),
+ GetRegisterName(reg),
+ GetRegisterSize(reg),
+ value);
+}
+
+bool
+RegisterContextPOSIXProcessMonitor_x86_64::WriteRegister(const unsigned reg,
+ const RegisterValue &value)
+{
+ unsigned reg_to_write = reg;
+ RegisterValue value_to_write = value;
+
+ // Check if this is a subregister of a full register.
+ const RegisterInfo *reg_info = GetRegisterInfoAtIndex(reg);
+ if (reg_info->invalidate_regs && (reg_info->invalidate_regs[0] != LLDB_INVALID_REGNUM))
+ {
+ RegisterValue full_value;
+ uint32_t full_reg = reg_info->invalidate_regs[0];
+ const RegisterInfo *full_reg_info = GetRegisterInfoAtIndex(full_reg);
+
+ // Read the full register.
+ if (ReadRegister(full_reg_info, full_value))
+ {
+ Error error;
+ ByteOrder byte_order = GetByteOrder();
+ uint8_t dst[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[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();
+#if defined(__FreeBSD__)
+ if (reg >= m_reg_info.first_dr)
+ return monitor.WriteDebugRegisterValue(m_thread.GetID(),
+ GetRegisterOffset(reg_to_write),
+ GetRegisterName(reg_to_write),
+ value_to_write);
+#endif
+ return monitor.WriteRegisterValue(m_thread.GetID(),
+ GetRegisterOffset(reg_to_write),
+ GetRegisterName(reg_to_write),
+ value_to_write);
+}
+
+bool
+RegisterContextPOSIXProcessMonitor_x86_64::ReadRegister(const RegisterInfo *reg_info, RegisterValue &value)
+{
+ if (!reg_info)
+ return false;
+
+ const uint32_t reg = reg_info->kinds[eRegisterKindLLDB];
+
+ if (IsFPR(reg, GetFPRType()))
+ {
+ 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];
+ }
+
+ bool success = ReadRegister(full_reg, value);
+
+ if (success)
+ {
+ // If our read was not aligned (for ah,bh,ch,dh), shift our returned value one byte to the right.
+ if (is_subreg && (reg_info->byte_offset & 0x1))
+ value.SetUInt64(value.GetAsUInt64() >> 8);
+
+ // If our return byte size was greater than the return value reg size, then
+ // use the type specified by reg_info rather than the uint64_t default
+ if (value.GetByteSize() > reg_info->byte_size)
+ value.SetType(reg_info);
+ }
+ return success;
+ }
+
+ if (reg_info->encoding == eEncodingVector)
+ {
+ ByteOrder byte_order = GetByteOrder();
+
+ if (byte_order != ByteOrder::eByteOrderInvalid)
+ {
+ if (reg >= m_reg_info.first_st && reg <= m_reg_info.last_st)
+ value.SetBytes(m_fpr.xstate.fxsave.stmm[reg - m_reg_info.first_st].bytes, reg_info->byte_size, byte_order);
+ if (reg >= m_reg_info.first_mm && reg <= m_reg_info.last_mm)
+ value.SetBytes(m_fpr.xstate.fxsave.stmm[reg - m_reg_info.first_mm].bytes, reg_info->byte_size, byte_order);
+ if (reg >= m_reg_info.first_xmm && reg <= m_reg_info.last_xmm)
+ value.SetBytes(m_fpr.xstate.fxsave.xmm[reg - m_reg_info.first_xmm].bytes, reg_info->byte_size, byte_order);
+ if (reg >= m_reg_info.first_ymm && reg <= m_reg_info.last_ymm)
+ {
+ // Concatenate ymm using the register halves in xmm.bytes and ymmh.bytes
+ if (GetFPRType() == eXSAVE && CopyXSTATEtoYMM(reg, byte_order))
+ value.SetBytes(m_ymm_set.ymm[reg - m_reg_info.first_ymm].bytes, reg_info->byte_size, byte_order);
+ else
+ return false;
+ }
+ return value.GetType() == RegisterValue::eTypeBytes;
+ }
+ return false;
+ }
+
+ // Get pointer to m_fpr.xstate.fxsave 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_x86_64::WriteRegister(const RegisterInfo *reg_info, const RegisterValue &value)
+{
+ const uint32_t reg = reg_info->kinds[eRegisterKindLLDB];
+
+ if (IsGPR(reg))
+ return WriteRegister(reg, value);
+
+ if (IsFPR(reg, GetFPRType()))
+ {
+ if (reg_info->encoding == eEncodingVector)
+ {
+ if (reg >= m_reg_info.first_st && reg <= m_reg_info.last_st)
+ ::memcpy (m_fpr.xstate.fxsave.stmm[reg - m_reg_info.first_st].bytes, value.GetBytes(), value.GetByteSize());
+
+ if (reg >= m_reg_info.first_mm && reg <= m_reg_info.last_mm)
+ ::memcpy (m_fpr.xstate.fxsave.stmm[reg - m_reg_info.first_mm].bytes, value.GetBytes(), value.GetByteSize());
+
+ if (reg >= m_reg_info.first_xmm && reg <= m_reg_info.last_xmm)
+ ::memcpy (m_fpr.xstate.fxsave.xmm[reg - m_reg_info.first_xmm].bytes, value.GetBytes(), value.GetByteSize());
+
+ if (reg >= m_reg_info.first_ymm && reg <= m_reg_info.last_ymm)
+ {
+ if (GetFPRType() != eXSAVE)
+ return false; // the target processor does not support AVX
+
+ // Store ymm register content, and split into the register halves in xmm.bytes and ymmh.bytes
+ ::memcpy (m_ymm_set.ymm[reg - m_reg_info.first_ymm].bytes, value.GetBytes(), value.GetByteSize());
+ if (false == CopyYMMtoXSTATE(reg, GetByteOrder()))
+ return false;
+ }
+ }
+ else
+ {
+ // Get pointer to m_fpr.xstate.fxsave variable and set the data to it.
+ assert (reg_info->byte_offset < sizeof(m_fpr));
+ uint8_t *dst = (uint8_t *)&m_fpr + reg_info->byte_offset;
+ switch (reg_info->byte_size)
+ {
+ case 2:
+ *(uint16_t *)dst = value.GetAsUInt16();
+ break;
+ case 4:
+ *(uint32_t *)dst = value.GetAsUInt32();
+ break;
+ case 8:
+ *(uint64_t *)dst = value.GetAsUInt64();
+ break;
+ default:
+ assert(false && "Unhandled data size.");
+ return false;
+ }
+ }
+
+ if (WriteFPR())
+ {
+ if (IsAVX(reg))
+ return CopyYMMtoXSTATE(reg, GetByteOrder());
+ return true;
+ }
+ }
+ return false;
+}
+
+bool
+RegisterContextPOSIXProcessMonitor_x86_64::ReadAllRegisterValues(DataBufferSP &data_sp)
+{
+ bool success = false;
+ data_sp.reset (new 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_x86_64, GetGPRSize());
+ dst += GetGPRSize();
+ if (GetFPRType() == eFXSAVE)
+ ::memcpy (dst, &m_fpr.xstate.fxsave, sizeof(m_fpr.xstate.fxsave));
+ }
+
+ if (GetFPRType() == eXSAVE)
+ {
+ ByteOrder byte_order = GetByteOrder();
+
+ // Assemble the YMM register content from the register halves.
+ for (uint32_t reg = m_reg_info.first_ymm; success && reg <= m_reg_info.last_ymm; ++reg)
+ success = CopyXSTATEtoYMM(reg, byte_order);
+
+ if (success)
+ {
+ // Copy the extended register state including the assembled ymm registers.
+ ::memcpy (dst, &m_fpr, sizeof(m_fpr));
+ }
+ }
+ }
+ return success;
+}
+
+bool
+RegisterContextPOSIXProcessMonitor_x86_64::WriteAllRegisterValues(const 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_x86_64, src, GetGPRSize());
+
+ if (WriteGPR())
+ {
+ src += GetGPRSize();
+ if (GetFPRType() == eFXSAVE)
+ ::memcpy (&m_fpr.xstate.fxsave, src, sizeof(m_fpr.xstate.fxsave));
+ if (GetFPRType() == eXSAVE)
+ ::memcpy (&m_fpr.xstate.xsave, src, sizeof(m_fpr.xstate.xsave));
+
+ success = WriteFPR();
+ if (success)
+ {
+ if (GetFPRType() == eXSAVE)
+ {
+ ByteOrder byte_order = GetByteOrder();
+
+ // Parse the YMM register content from the register halves.
+ for (uint32_t reg = m_reg_info.first_ymm; success && reg <= m_reg_info.last_ymm; ++reg)
+ success = CopyYMMtoXSTATE(reg, byte_order);
+ }
+ }
+ }
+ }
+ }
+ return success;
+}
+
+uint32_t
+RegisterContextPOSIXProcessMonitor_x86_64::SetHardwareWatchpoint(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_x86_64::ClearHardwareWatchpoint(uint32_t hw_index)
+{
+ if (hw_index < NumSupportedHardwareWatchpoints())
+ {
+ RegisterValue current_dr7_bits;
+
+ if (ReadRegister(m_reg_info.first_dr + 7, current_dr7_bits))
+ {
+ uint64_t new_dr7_bits = current_dr7_bits.GetAsUInt64() & ~(3 << (2*hw_index));
+
+ if (WriteRegister(m_reg_info.first_dr + 7, RegisterValue(new_dr7_bits)))
+ return true;
+ }
+ }
+
+ return false;
+}
+
+bool
+RegisterContextPOSIXProcessMonitor_x86_64::HardwareSingleStep(bool enable)
+{
+ enum { TRACE_BIT = 0x100 };
+ uint64_t rflags;
+
+ if ((rflags = ReadRegisterAsUnsigned(m_reg_info.gpr_flags, -1UL)) == -1UL)
+ return false;
+
+ if (enable)
+ {
+ if (rflags & TRACE_BIT)
+ return true;
+
+ rflags |= TRACE_BIT;
+ }
+ else
+ {
+ if (!(rflags & TRACE_BIT))
+ return false;
+
+ rflags &= ~TRACE_BIT;
+ }
+
+ return WriteRegisterFromUnsigned(m_reg_info.gpr_flags, rflags);
+}
+
+bool
+RegisterContextPOSIXProcessMonitor_x86_64::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_x86_64::GetRegisterIndexFromOffset(unsigned offset)
+{
+ unsigned reg;
+ for (reg = 0; reg < m_reg_info.num_registers; reg++)
+ {
+ if (GetRegisterInfo()[reg].byte_offset == offset)
+ break;
+ }
+ assert(reg < m_reg_info.num_registers && "Invalid register offset.");
+ return reg;
+}
+
+bool
+RegisterContextPOSIXProcessMonitor_x86_64::IsWatchpointHit(uint32_t hw_index)
+{
+ bool is_hit = false;
+
+ if (m_watchpoints_initialized == false)
+ {
+ // Reset the debug status and debug control registers
+ RegisterValue zero_bits = RegisterValue(uint64_t(0));
+ if (!WriteRegister(m_reg_info.first_dr + 6, zero_bits) || !WriteRegister(m_reg_info.first_dr + 7, zero_bits))
+ assert(false && "Could not initialize watchpoint registers");
+ m_watchpoints_initialized = true;
+ }
+
+ if (hw_index < NumSupportedHardwareWatchpoints())
+ {
+ RegisterValue value;
+
+ if (ReadRegister(m_reg_info.first_dr + 6, value))
+ {
+ uint64_t val = value.GetAsUInt64();
+ is_hit = val & (1 << hw_index);
+ }
+ }
+
+ return is_hit;
+}
+
+bool
+RegisterContextPOSIXProcessMonitor_x86_64::ClearWatchpointHits()
+{
+ return WriteRegister(m_reg_info.first_dr + 6, RegisterValue((uint64_t)0));
+}
+
+addr_t
+RegisterContextPOSIXProcessMonitor_x86_64::GetWatchpointAddress(uint32_t hw_index)
+{
+ addr_t wp_monitor_addr = LLDB_INVALID_ADDRESS;
+
+ if (hw_index < NumSupportedHardwareWatchpoints())
+ {
+ if (!IsWatchpointVacant(hw_index))
+ {
+ RegisterValue value;
+
+ if (ReadRegister(m_reg_info.first_dr + hw_index, value))
+ wp_monitor_addr = value.GetAsUInt64();
+ }
+ }
+
+ return wp_monitor_addr;
+}
+
+bool
+RegisterContextPOSIXProcessMonitor_x86_64::IsWatchpointVacant(uint32_t hw_index)
+{
+ bool is_vacant = false;
+ RegisterValue value;
+
+ assert(hw_index < NumSupportedHardwareWatchpoints());
+
+ if (m_watchpoints_initialized == false)
+ {
+ // Reset the debug status and debug control registers
+ RegisterValue zero_bits = RegisterValue(uint64_t(0));
+ if (!WriteRegister(m_reg_info.first_dr + 6, zero_bits) || !WriteRegister(m_reg_info.first_dr + 7, zero_bits))
+ assert(false && "Could not initialize watchpoint registers");
+ m_watchpoints_initialized = true;
+ }
+
+ if (ReadRegister(m_reg_info.first_dr + 7, value))
+ {
+ uint64_t val = value.GetAsUInt64();
+ is_vacant = (val & (3 << 2*hw_index)) == 0;
+ }
+
+ return is_vacant;
+}
+
+bool
+RegisterContextPOSIXProcessMonitor_x86_64::SetHardwareWatchpointWithIndex(addr_t addr, size_t size,
+ bool read, bool write,
+ uint32_t hw_index)
+{
+ const uint32_t num_hw_watchpoints = NumSupportedHardwareWatchpoints();
+
+ if (num_hw_watchpoints == 0 || hw_index >= num_hw_watchpoints)
+ return false;
+
+ if (!(size == 1 || size == 2 || size == 4 || size == 8))
+ return false;
+
+ if (read == false && write == false)
+ return false;
+
+ if (!IsWatchpointVacant(hw_index))
+ return false;
+
+ // Set both dr7 (debug control register) and dri (debug address register).
+
+ // dr7{7-0} encodes the local/global enable bits:
+ // global enable --. .-- local enable
+ // | |
+ // v v
+ // dr0 -> bits{1-0}
+ // dr1 -> bits{3-2}
+ // dr2 -> bits{5-4}
+ // dr3 -> bits{7-6}
+ //
+ // dr7{31-16} encodes the rw/len bits:
+ // b_x+3, b_x+2, b_x+1, b_x
+ // where bits{x+1, x} => rw
+ // 0b00: execute, 0b01: write, 0b11: read-or-write,
+ // 0b10: io read-or-write (unused)
+ // and bits{x+3, x+2} => len
+ // 0b00: 1-byte, 0b01: 2-byte, 0b11: 4-byte, 0b10: 8-byte
+ //
+ // dr0 -> bits{19-16}
+ // dr1 -> bits{23-20}
+ // dr2 -> bits{27-24}
+ // dr3 -> bits{31-28}
+ if (hw_index < num_hw_watchpoints)
+ {
+ RegisterValue current_dr7_bits;
+
+ if (ReadRegister(m_reg_info.first_dr + 7, current_dr7_bits))
+ {
+ uint64_t new_dr7_bits = current_dr7_bits.GetAsUInt64() |
+ (1 << (2*hw_index) |
+ size_and_rw_bits(size, read, write) <<
+ (16+4*hw_index));
+
+ if (WriteRegister(m_reg_info.first_dr + hw_index, RegisterValue(addr)) &&
+ WriteRegister(m_reg_info.first_dr + 7, RegisterValue(new_dr7_bits)))
+ return true;
+ }
+ }
+
+ return false;
+}
+
+uint32_t
+RegisterContextPOSIXProcessMonitor_x86_64::NumSupportedHardwareWatchpoints()
+{
+ // Available debug address registers: dr0, dr1, dr2, dr3
+ return 4;
+}
+