Files
clang-p2996/lldb/source/Plugins/Instruction/ARM/EmulationStateARM.cpp
Ulrich Weigand 91a2ad182d Fix ARM instruction emulation tests on big-endian systems
Running the ARM instruction emulation test on a big-endian system
would fail, since the code doesn't respect endianness properly.

In EmulateInstructionARM::TestEmulation, code assumes that an
instruction opcode read in from the test file is in target byte
order, but it was in fact read in in host byte order.

More difficult to fix, the EmulationStateARM structure models
the overlapping sregs and dregs by a union in _sd_regs.  This
only works correctly if the host is a little-endian system.
I've removed the union in favor of a simple array containing
the 32 sregs, and changed any code accessing dregs to explicitly
use the correct two sregs overlaying that dreg in the proper
target order.

Also, the EmulationStateARM::ReadPseudoMemory and WritePseudoMemory
track memory as a map of uint32_t values in host byte order, and
implement 64-bit memory accessing by splitting them up into two
uint32_t ones.  However, callers expect memory contents to be
provided in the form of a byte array (in target byte order).
This means the uint32_t contents need to be byte-swapped on
BE systems, and when splitting up a 64-bit access into two 32-bit
ones, byte order has to be respected.

Differential Revision: http://reviews.llvm.org/D18984

llvm-svn: 266314
2016-04-14 14:34:19 +00:00

419 lines
12 KiB
C++

//===-- EmulationStateARM.cpp -----------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "EmulationStateARM.h"
#include "lldb/Core/RegisterValue.h"
#include "lldb/Core/Scalar.h"
#include "lldb/Interpreter/OptionValueArray.h"
#include "lldb/Interpreter/OptionValueDictionary.h"
#include "lldb/Target/StackFrame.h"
#include "lldb/Target/RegisterContext.h"
#include "Utility/ARM_DWARF_Registers.h"
using namespace lldb;
using namespace lldb_private;
EmulationStateARM::EmulationStateARM () :
m_gpr (),
m_vfp_regs (),
m_memory ()
{
ClearPseudoRegisters();
}
EmulationStateARM::~EmulationStateARM ()
{
}
bool
EmulationStateARM::LoadPseudoRegistersFromFrame (StackFrame &frame)
{
RegisterContext *reg_ctx = frame.GetRegisterContext().get();
bool success = true;
uint32_t reg_num;
for (int i = dwarf_r0; i < dwarf_r0 + 17; ++i)
{
reg_num = reg_ctx->ConvertRegisterKindToRegisterNumber (eRegisterKindDWARF, i);
const RegisterInfo *reg_info = reg_ctx->GetRegisterInfoAtIndex (reg_num);
RegisterValue reg_value;
if (reg_ctx->ReadRegister (reg_info, reg_value))
{
m_gpr[i - dwarf_r0] = reg_value.GetAsUInt32();
}
else
success = false;
}
for (int i = dwarf_d0; i < dwarf_d0 + 32; ++i)
{
reg_num = reg_ctx->ConvertRegisterKindToRegisterNumber (eRegisterKindDWARF, i);
RegisterValue reg_value;
const RegisterInfo *reg_info = reg_ctx->GetRegisterInfoAtIndex (reg_num);
if (reg_ctx->ReadRegister (reg_info, reg_value))
{
uint64_t value = reg_value.GetAsUInt64();
uint32_t idx = i - dwarf_d0;
if (i < 16)
{
m_vfp_regs.s_regs[idx * 2] = (uint32_t)value;
m_vfp_regs.s_regs[idx * 2 + 1] = (uint32_t)(value >> 32);
}
else
m_vfp_regs.d_regs[idx - 16] = value;
}
else
success = false;
}
return success;
}
bool
EmulationStateARM::StorePseudoRegisterValue (uint32_t reg_num, uint64_t value)
{
if ((dwarf_r0 <= reg_num) && (reg_num <= dwarf_cpsr))
m_gpr[reg_num - dwarf_r0] = (uint32_t) value;
else if ((dwarf_s0 <= reg_num) && (reg_num <= dwarf_s31))
{
uint32_t idx = reg_num - dwarf_s0;
m_vfp_regs.s_regs[idx] = (uint32_t)value;
}
else if ((dwarf_d0 <= reg_num) && (reg_num <= dwarf_d31))
{
uint32_t idx = reg_num - dwarf_d0;
if (idx < 16)
{
m_vfp_regs.s_regs[idx * 2] = (uint32_t)value;
m_vfp_regs.s_regs[idx * 2 + 1] = (uint32_t)(value >> 32);
}
else
m_vfp_regs.d_regs[idx - 16] = value;
}
else
return false;
return true;
}
uint64_t
EmulationStateARM::ReadPseudoRegisterValue (uint32_t reg_num, bool &success)
{
uint64_t value = 0;
success = true;
if ((dwarf_r0 <= reg_num) && (reg_num <= dwarf_cpsr))
value = m_gpr[reg_num - dwarf_r0];
else if ((dwarf_s0 <= reg_num) && (reg_num <= dwarf_s31))
{
uint32_t idx = reg_num - dwarf_s0;
value = m_vfp_regs.d_regs[idx];
}
else if ((dwarf_d0 <= reg_num) && (reg_num <= dwarf_d31))
{
uint32_t idx = reg_num - dwarf_d0;
if (idx < 16)
value = (uint64_t)m_vfp_regs.s_regs[idx * 2] | ((uint64_t)m_vfp_regs.s_regs[idx * 2 + 1] >> 32);
else
value = m_vfp_regs.d_regs[idx - 16];
}
else
success = false;
return value;
}
void
EmulationStateARM::ClearPseudoRegisters ()
{
for (int i = 0; i < 17; ++i)
m_gpr[i] = 0;
for (int i = 0; i < 32; ++i)
m_vfp_regs.s_regs[i] = 0;
for (int i = 0; i < 16; ++i)
m_vfp_regs.d_regs[i] = 0;
}
void
EmulationStateARM::ClearPseudoMemory ()
{
m_memory.clear();
}
bool
EmulationStateARM::StoreToPseudoAddress (lldb::addr_t p_address, uint32_t value)
{
m_memory[p_address] = value;
return true;
}
uint32_t
EmulationStateARM::ReadFromPseudoAddress (lldb::addr_t p_address, bool &success)
{
std::map<lldb::addr_t,uint32_t>::iterator pos;
uint32_t ret_val = 0;
success = true;
pos = m_memory.find(p_address);
if (pos != m_memory.end())
ret_val = pos->second;
else
success = false;
return ret_val;
}
size_t
EmulationStateARM::ReadPseudoMemory (EmulateInstruction *instruction,
void *baton,
const EmulateInstruction::Context &context,
lldb::addr_t addr,
void *dst,
size_t length)
{
if (!baton)
return 0;
bool success = true;
EmulationStateARM *pseudo_state = (EmulationStateARM *) baton;
if (length <= 4)
{
uint32_t value = pseudo_state->ReadFromPseudoAddress (addr, success);
if (!success)
return 0;
if (endian::InlHostByteOrder() == lldb::eByteOrderBig)
value = llvm::ByteSwap_32 (value);
*((uint32_t *) dst) = value;
}
else if (length == 8)
{
uint32_t value1 = pseudo_state->ReadFromPseudoAddress (addr, success);
if (!success)
return 0;
uint32_t value2 = pseudo_state->ReadFromPseudoAddress (addr + 4, success);
if (!success)
return 0;
if (endian::InlHostByteOrder() == lldb::eByteOrderBig)
{
value1 = llvm::ByteSwap_32 (value1);
value2 = llvm::ByteSwap_32 (value2);
}
((uint32_t *) dst)[0] = value1;
((uint32_t *) dst)[1] = value2;
}
else
success = false;
if (success)
return length;
return 0;
}
size_t
EmulationStateARM::WritePseudoMemory (EmulateInstruction *instruction,
void *baton,
const EmulateInstruction::Context &context,
lldb::addr_t addr,
const void *dst,
size_t length)
{
if (!baton)
return 0;
EmulationStateARM *pseudo_state = (EmulationStateARM *) baton;
if (length <= 4)
{
uint32_t value = *((const uint32_t *) dst);
if (endian::InlHostByteOrder() == lldb::eByteOrderBig)
value = llvm::ByteSwap_32 (value);
pseudo_state->StoreToPseudoAddress (addr, value);
return length;
}
else if (length == 8)
{
uint32_t value1 = ((const uint32_t *) dst)[0];
uint32_t value2 = ((const uint32_t *) dst)[1];
if (endian::InlHostByteOrder() == lldb::eByteOrderBig)
{
value1 = llvm::ByteSwap_32 (value1);
value2 = llvm::ByteSwap_32 (value2);
}
pseudo_state->StoreToPseudoAddress (addr, value1);
pseudo_state->StoreToPseudoAddress (addr + 4, value2);
return length;
}
return 0;
}
bool
EmulationStateARM::ReadPseudoRegister (EmulateInstruction *instruction,
void *baton,
const lldb_private::RegisterInfo *reg_info,
lldb_private::RegisterValue &reg_value)
{
if (!baton || !reg_info)
return false;
bool success = true;
EmulationStateARM *pseudo_state = (EmulationStateARM *) baton;
const uint32_t dwarf_reg_num = reg_info->kinds[eRegisterKindDWARF];
assert (dwarf_reg_num != LLDB_INVALID_REGNUM);
uint64_t reg_uval = pseudo_state->ReadPseudoRegisterValue (dwarf_reg_num, success);
if (success)
success = reg_value.SetUInt(reg_uval, reg_info->byte_size);
return success;
}
bool
EmulationStateARM::WritePseudoRegister (EmulateInstruction *instruction,
void *baton,
const EmulateInstruction::Context &context,
const lldb_private::RegisterInfo *reg_info,
const lldb_private::RegisterValue &reg_value)
{
if (!baton || !reg_info)
return false;
EmulationStateARM *pseudo_state = (EmulationStateARM *) baton;
const uint32_t dwarf_reg_num = reg_info->kinds[eRegisterKindDWARF];
assert (dwarf_reg_num != LLDB_INVALID_REGNUM);
return pseudo_state->StorePseudoRegisterValue (dwarf_reg_num, reg_value.GetAsUInt64());
}
bool
EmulationStateARM::CompareState (EmulationStateARM &other_state)
{
bool match = true;
for (int i = 0; match && i < 17; ++i)
{
if (m_gpr[i] != other_state.m_gpr[i])
match = false;
}
for (int i = 0; match && i < 32; ++i)
{
if (m_vfp_regs.s_regs[i] != other_state.m_vfp_regs.s_regs[i])
match = false;
}
for (int i = 0; match && i < 16; ++i)
{
if (m_vfp_regs.d_regs[i] != other_state.m_vfp_regs.d_regs[i])
match = false;
}
return match;
}
bool
EmulationStateARM::LoadStateFromDictionary (OptionValueDictionary *test_data)
{
static ConstString memory_key ("memory");
static ConstString registers_key ("registers");
if (!test_data)
return false;
OptionValueSP value_sp = test_data->GetValueForKey (memory_key);
// Load memory, if present.
if (value_sp.get() != NULL)
{
static ConstString address_key ("address");
static ConstString data_key ("data");
uint64_t start_address = 0;
OptionValueDictionary *mem_dict = value_sp->GetAsDictionary();
value_sp = mem_dict->GetValueForKey (address_key);
if (value_sp.get() == NULL)
return false;
else
start_address = value_sp->GetUInt64Value ();
value_sp = mem_dict->GetValueForKey (data_key);
OptionValueArray *mem_array = value_sp->GetAsArray();
if (!mem_array)
return false;
uint32_t num_elts = mem_array->GetSize();
uint32_t address = (uint32_t) start_address;
for (uint32_t i = 0; i < num_elts; ++i)
{
value_sp = mem_array->GetValueAtIndex (i);
if (value_sp.get() == NULL)
return false;
uint64_t value = value_sp->GetUInt64Value();
StoreToPseudoAddress (address, value);
address = address + 4;
}
}
value_sp = test_data->GetValueForKey (registers_key);
if (value_sp.get() == NULL)
return false;
// Load General Registers
OptionValueDictionary *reg_dict = value_sp->GetAsDictionary ();
StreamString sstr;
for (int i = 0; i < 16; ++i)
{
sstr.Clear();
sstr.Printf ("r%d", i);
ConstString reg_name (sstr.GetData());
value_sp = reg_dict->GetValueForKey (reg_name);
if (value_sp.get() == NULL)
return false;
uint64_t reg_value = value_sp->GetUInt64Value();
StorePseudoRegisterValue (dwarf_r0 + i, reg_value);
}
static ConstString cpsr_name ("cpsr");
value_sp = reg_dict->GetValueForKey (cpsr_name);
if (value_sp.get() == NULL)
return false;
StorePseudoRegisterValue (dwarf_cpsr, value_sp->GetUInt64Value());
// Load s/d Registers
for (int i = 0; i < 32; ++i)
{
sstr.Clear();
sstr.Printf ("s%d", i);
ConstString reg_name (sstr.GetData());
value_sp = reg_dict->GetValueForKey (reg_name);
if (value_sp.get() == NULL)
return false;
uint64_t reg_value = value_sp->GetUInt64Value();
StorePseudoRegisterValue (dwarf_s0 + i, reg_value);
}
return true;
}