Files
clang-p2996/lldb/source/Plugins/Disassembler/llvm/DisassemblerLLVM.cpp
Greg Clayton d9e416c0ea The second part in thread hardening the internals of LLDB where we make
the lldb_private::StackFrame objects hold onto a weak pointer to the thread
object. The lldb_private::StackFrame objects the the most volatile objects
we have as when we are doing single stepping, frames can often get lost or
thrown away, only to be re-created as another object that still refers to the
same frame. We have another bug tracking that. But we need to be able to 
have frames no longer be able to get the thread when they are not part of
a thread anymore, and this is the first step (this fix makes that possible
but doesn't implement it yet).

Also changed lldb_private::ExecutionContextScope to return shared pointers to
all objects in the execution context to further thread harden the internals.

llvm-svn: 150871
2012-02-18 05:35:26 +00:00

800 lines
26 KiB
C++

//===-- DisassemblerLLVM.cpp ------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "DisassemblerLLVM.h"
#include "llvm-c/EnhancedDisassembly.h"
#include "llvm/Support/TargetSelect.h"
#include "lldb/Core/Address.h"
#include "lldb/Core/DataExtractor.h"
#include "lldb/Core/Disassembler.h"
#include "lldb/Core/Module.h"
#include "lldb/Core/PluginManager.h"
#include "lldb/Core/Stream.h"
#include "lldb/Core/StreamString.h"
#include "lldb/Symbol/SymbolContext.h"
#include "lldb/Target/ExecutionContext.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/RegisterContext.h"
#include "lldb/Target/Target.h"
#include <assert.h>
using namespace lldb;
using namespace lldb_private;
static int
DataExtractorByteReader (uint8_t *byte, uint64_t address, void *arg)
{
DataExtractor &extractor = *((DataExtractor *)arg);
if (extractor.ValidOffset(address))
{
*byte = *(extractor.GetDataStart() + address);
return 0;
}
else
{
return -1;
}
}
namespace {
struct RegisterReaderArg {
const lldb::addr_t instructionPointer;
const EDDisassemblerRef disassembler;
RegisterReaderArg(lldb::addr_t ip,
EDDisassemblerRef dis) :
instructionPointer(ip),
disassembler(dis)
{
}
};
}
static int IPRegisterReader(uint64_t *value, unsigned regID, void* arg)
{
uint64_t instructionPointer = ((RegisterReaderArg*)arg)->instructionPointer;
EDDisassemblerRef disassembler = ((RegisterReaderArg*)arg)->disassembler;
if (EDRegisterIsProgramCounter(disassembler, regID)) {
*value = instructionPointer;
return 0;
}
return -1;
}
InstructionLLVM::InstructionLLVM (const Address &addr,
AddressClass addr_class,
EDDisassemblerRef disassembler,
llvm::Triple::ArchType arch_type) :
Instruction (addr, addr_class),
m_disassembler (disassembler),
m_inst (NULL),
m_arch_type (arch_type)
{
}
InstructionLLVM::~InstructionLLVM()
{
if (m_inst)
{
EDReleaseInst(m_inst);
m_inst = NULL;
}
}
static void
PadString(Stream *s, const std::string &str, size_t width)
{
int diff = width - str.length();
if (diff > 0)
s->Printf("%s%*.*s", str.c_str(), diff, diff, "");
else
s->Printf("%s ", str.c_str());
}
static void
AddSymbolicInfo (const ExecutionContext *exe_ctx,
StreamString &comment,
uint64_t operand_value,
const Address &inst_addr)
{
Address so_addr;
Target *target = NULL;
if (exe_ctx)
target = exe_ctx->GetTargetPtr();
if (target && !target->GetSectionLoadList().IsEmpty())
{
if (target->GetSectionLoadList().ResolveLoadAddress(operand_value, so_addr))
so_addr.Dump (&comment,
exe_ctx ? exe_ctx->GetBestExecutionContextScope() : NULL,
Address::DumpStyleResolvedDescriptionNoModule,
Address::DumpStyleSectionNameOffset);
}
else
{
Module *module = inst_addr.GetModulePtr();
if (module)
{
if (module->ResolveFileAddress(operand_value, so_addr))
so_addr.Dump (&comment,
exe_ctx ? exe_ctx->GetBestExecutionContextScope() : NULL,
Address::DumpStyleResolvedDescriptionNoModule,
Address::DumpStyleSectionNameOffset);
}
}
}
#include "llvm/ADT/StringRef.h"
static inline void StripSpaces(llvm::StringRef &Str)
{
while (!Str.empty() && isspace(Str[0]))
Str = Str.substr(1);
while (!Str.empty() && isspace(Str.back()))
Str = Str.substr(0, Str.size()-1);
}
static inline void RStrip(llvm::StringRef &Str, char c)
{
if (!Str.empty() && Str.back() == c)
Str = Str.substr(0, Str.size()-1);
}
// Aligns the raw disassembly (passed as 'str') with the rest of edis'ed disassembly output.
// This is called from non-raw mode when edis of the current m_inst fails for some reason.
static void
Align(Stream *s, const char *str, size_t opcodeColWidth, size_t operandColWidth)
{
llvm::StringRef raw_disasm(str);
StripSpaces(raw_disasm);
// Split the raw disassembly into opcode and operands.
std::pair<llvm::StringRef, llvm::StringRef> p = raw_disasm.split('\t');
PadString(s, p.first, opcodeColWidth);
if (!p.second.empty())
PadString(s, p.second, operandColWidth);
}
#define AlignPC(pc_val) (pc_val & 0xFFFFFFFC)
void
InstructionLLVM::Dump
(
Stream *s,
uint32_t max_opcode_byte_size,
bool show_address,
bool show_bytes,
const ExecutionContext* exe_ctx,
bool raw
)
{
const size_t opcodeColumnWidth = 7;
const size_t operandColumnWidth = 25;
ExecutionContextScope *exe_scope = NULL;
if (exe_ctx)
exe_scope = exe_ctx->GetBestExecutionContextScope();
// If we have an address, print it out
if (GetAddress().IsValid() && show_address)
{
if (GetAddress().Dump (s,
exe_scope,
Address::DumpStyleLoadAddress,
Address::DumpStyleModuleWithFileAddress,
0))
s->PutCString(": ");
}
// If we are supposed to show bytes, "bytes" will be non-NULL.
if (show_bytes)
{
if (m_opcode.GetType() == Opcode::eTypeBytes)
{
// x86_64 and i386 are the only ones that use bytes right now so
// pad out the byte dump to be able to always show 15 bytes (3 chars each)
// plus a space
if (max_opcode_byte_size > 0)
m_opcode.Dump (s, max_opcode_byte_size * 3 + 1);
else
m_opcode.Dump (s, 15 * 3 + 1);
}
else
{
// Else, we have ARM which can show up to a uint32_t 0x00000000 (10 spaces)
// plus two for padding...
if (max_opcode_byte_size > 0)
m_opcode.Dump (s, max_opcode_byte_size * 3 + 1);
else
m_opcode.Dump (s, 12);
}
}
int numTokens = -1;
// FIXME!!!
/* Remove the following section of code related to force_raw .... */
/*
bool force_raw = m_arch_type == llvm::Triple::arm ||
m_arch_type == llvm::Triple::thumb;
if (!raw)
raw = force_raw;
*/
/* .... when we fix the edis for arm/thumb. */
if (!raw)
numTokens = EDNumTokens(m_inst);
int currentOpIndex = -1;
bool printTokenized = false;
if (numTokens != -1 && !raw)
{
addr_t base_addr = LLDB_INVALID_ADDRESS;
uint32_t addr_nibble_size = 8;
Target *target = NULL;
if (exe_ctx)
target = exe_ctx->GetTargetPtr();
if (target)
{
if (!target->GetSectionLoadList().IsEmpty())
base_addr = GetAddress().GetLoadAddress (target);
addr_nibble_size = target->GetArchitecture().GetAddressByteSize() * 2;
}
if (base_addr == LLDB_INVALID_ADDRESS)
base_addr = GetAddress().GetFileAddress ();
lldb::addr_t PC = base_addr + EDInstByteSize(m_inst);
// When executing an ARM instruction, PC reads as the address of the
// current instruction plus 8. And for Thumb, it is plus 4.
if (m_arch_type == llvm::Triple::arm)
PC = base_addr + 8;
else if (m_arch_type == llvm::Triple::thumb)
PC = base_addr + 4;
RegisterReaderArg rra(PC, m_disassembler);
printTokenized = true;
// Handle the opcode column.
StreamString opcode;
int tokenIndex = 0;
EDTokenRef token;
const char *tokenStr;
if (EDGetToken(&token, m_inst, tokenIndex)) // 0 on success
printTokenized = false;
else if (!EDTokenIsOpcode(token))
printTokenized = false;
else if (EDGetTokenString(&tokenStr, token)) // 0 on success
printTokenized = false;
if (printTokenized)
{
// Put the token string into our opcode string
opcode.PutCString(tokenStr);
// If anything follows, it probably starts with some whitespace. Skip it.
if (++tokenIndex < numTokens)
{
if (EDGetToken(&token, m_inst, tokenIndex)) // 0 on success
printTokenized = false;
else if (!EDTokenIsWhitespace(token))
printTokenized = false;
}
++tokenIndex;
}
// Handle the operands and the comment.
StreamString operands;
StreamString comment;
if (printTokenized)
{
bool show_token = false;
for (; tokenIndex < numTokens; ++tokenIndex)
{
if (EDGetToken(&token, m_inst, tokenIndex))
return;
int operandIndex = EDOperandIndexForToken(token);
if (operandIndex >= 0)
{
if (operandIndex != currentOpIndex)
{
show_token = true;
currentOpIndex = operandIndex;
EDOperandRef operand;
if (!EDGetOperand(&operand, m_inst, currentOpIndex))
{
if (EDOperandIsMemory(operand))
{
uint64_t operand_value;
if (!EDEvaluateOperand(&operand_value, operand, IPRegisterReader, &rra))
{
if (EDInstIsBranch(m_inst))
{
operands.Printf("0x%*.*llx ", addr_nibble_size, addr_nibble_size, operand_value);
show_token = false;
}
else
{
// Put the address value into the comment
comment.Printf("0x%*.*llx ", addr_nibble_size, addr_nibble_size, operand_value);
}
AddSymbolicInfo(exe_ctx, comment, operand_value, GetAddress());
} // EDEvaluateOperand
} // EDOperandIsMemory
} // EDGetOperand
} // operandIndex != currentOpIndex
} // operandIndex >= 0
if (show_token)
{
if (EDGetTokenString(&tokenStr, token))
{
printTokenized = false;
break;
}
operands.PutCString(tokenStr);
}
} // for (tokenIndex)
// FIXME!!!
// Workaround for llvm::tB's operands not properly parsed by ARMAsmParser.
if (m_arch_type == llvm::Triple::thumb && opcode.GetString() == "b") {
const char *inst_str;
const char *pos = NULL;
operands.Clear(); comment.Clear();
if (EDGetInstString(&inst_str, m_inst) == 0 && (pos = strstr(inst_str, "#")) != NULL) {
uint64_t operand_value = PC + atoi(++pos);
// Put the address value into the operands.
operands.Printf("0x%8.8llx ", operand_value);
AddSymbolicInfo(exe_ctx, comment, operand_value, GetAddress());
}
}
// Yet more workaround for "bl #..." and "blx #...".
if ((m_arch_type == llvm::Triple::arm || m_arch_type == llvm::Triple::thumb) &&
(opcode.GetString() == "bl" || opcode.GetString() == "blx")) {
const char *inst_str;
const char *pos = NULL;
operands.Clear(); comment.Clear();
if (EDGetInstString(&inst_str, m_inst) == 0 && (pos = strstr(inst_str, "#")) != NULL) {
if (m_arch_type == llvm::Triple::thumb && opcode.GetString() == "blx") {
// A8.6.23 BLX (immediate)
// Target Address = Align(PC,4) + offset value
PC = AlignPC(PC);
}
uint64_t operand_value = PC + atoi(++pos);
// Put the address value into the comment.
comment.Printf("0x%8.8llx ", operand_value);
// And the original token string into the operands.
llvm::StringRef Str(pos - 1);
RStrip(Str, '\n');
operands.PutCString(Str.str().c_str());
AddSymbolicInfo(exe_ctx, comment, operand_value, GetAddress());
}
}
// END of workaround.
// If both operands and comment are empty, we will just print out
// the raw disassembly.
if (operands.GetString().empty() && comment.GetString().empty())
{
const char *str;
if (EDGetInstString(&str, m_inst))
return;
Align(s, str, opcodeColumnWidth, operandColumnWidth);
}
else
{
PadString(s, opcode.GetString(), opcodeColumnWidth);
if (comment.GetString().empty())
s->PutCString(operands.GetString().c_str());
else
{
PadString(s, operands.GetString(), operandColumnWidth);
s->PutCString("; ");
s->PutCString(comment.GetString().c_str());
} // else (comment.GetString().empty())
} // else (operands.GetString().empty() && comment.GetString().empty())
} // printTokenized
} // numTokens != -1
if (!printTokenized)
{
const char *str;
if (EDGetInstString(&str, m_inst)) // 0 on success
return;
if (raw)
s->Write(str, strlen(str) - 1);
else
{
// EDis fails to parse the tokens of this inst. Need to align this
// raw disassembly's opcode with the rest of output.
Align(s, str, opcodeColumnWidth, operandColumnWidth);
}
}
}
void
InstructionLLVM::CalculateMnemonicOperandsAndComment (ExecutionContextScope *exe_scope)
{
const int num_tokens = EDNumTokens(m_inst);
if (num_tokens > 0)
{
const char *token_cstr = NULL;
int currentOpIndex = -1;
StreamString comment;
uint32_t addr_nibble_size = 8;
addr_t base_addr = LLDB_INVALID_ADDRESS;
ExecutionContext exe_ctx (exe_scope);
Target *target = exe_ctx.GetTargetPtr();
if (target && !target->GetSectionLoadList().IsEmpty())
base_addr = GetAddress().GetLoadAddress (target);
if (base_addr == LLDB_INVALID_ADDRESS)
base_addr = GetAddress().GetFileAddress ();
addr_nibble_size = target->GetArchitecture().GetAddressByteSize() * 2;
lldb::addr_t PC = base_addr + EDInstByteSize(m_inst);
// When executing an ARM instruction, PC reads as the address of the
// current instruction plus 8. And for Thumb, it is plus 4.
if (m_arch_type == llvm::Triple::arm)
PC = base_addr + 8;
else if (m_arch_type == llvm::Triple::thumb)
PC = base_addr + 4;
RegisterReaderArg rra(PC, m_disassembler);
for (int token_idx = 0; token_idx < num_tokens; ++token_idx)
{
EDTokenRef token;
if (EDGetToken(&token, m_inst, token_idx))
break;
if (EDTokenIsOpcode(token) == 1)
{
if (EDGetTokenString(&token_cstr, token) == 0) // 0 on success
{
if (token_cstr)
m_opcode_name.assign(token_cstr);
}
}
else
{
int operandIndex = EDOperandIndexForToken(token);
if (operandIndex >= 0)
{
if (operandIndex != currentOpIndex)
{
currentOpIndex = operandIndex;
EDOperandRef operand;
if (!EDGetOperand(&operand, m_inst, currentOpIndex))
{
if (EDOperandIsMemory(operand))
{
uint64_t operand_value;
if (!EDEvaluateOperand(&operand_value, operand, IPRegisterReader, &rra))
{
comment.Printf("0x%*.*llx ", addr_nibble_size, addr_nibble_size, operand_value);
AddSymbolicInfo (&exe_ctx, comment, operand_value, GetAddress());
}
}
}
}
}
if (m_mnemocics.empty() && EDTokenIsWhitespace (token) == 1)
continue;
if (EDGetTokenString (&token_cstr, token))
break;
m_mnemocics.append (token_cstr);
}
}
// FIXME!!!
// Workaround for llvm::tB's operands not properly parsed by ARMAsmParser.
if (m_arch_type == llvm::Triple::thumb && m_opcode_name.compare("b") == 0)
{
const char *inst_str;
const char *pos = NULL;
comment.Clear();
if (EDGetInstString(&inst_str, m_inst) == 0 && (pos = strstr(inst_str, "#")) != NULL)
{
uint64_t operand_value = PC + atoi(++pos);
// Put the address value into the operands.
comment.Printf("0x%*.*llx ", addr_nibble_size, addr_nibble_size, operand_value);
AddSymbolicInfo (&exe_ctx, comment, operand_value, GetAddress());
}
}
// Yet more workaround for "bl #..." and "blx #...".
if ((m_arch_type == llvm::Triple::arm || m_arch_type == llvm::Triple::thumb) &&
(m_opcode_name.compare("bl") == 0 || m_opcode_name.compare("blx") == 0))
{
const char *inst_str;
const char *pos = NULL;
comment.Clear();
if (EDGetInstString(&inst_str, m_inst) == 0 && (pos = strstr(inst_str, "#")) != NULL)
{
if (m_arch_type == llvm::Triple::thumb && m_opcode_name.compare("blx") == 0)
{
// A8.6.23 BLX (immediate)
// Target Address = Align(PC,4) + offset value
PC = AlignPC(PC);
}
uint64_t operand_value = PC + atoi(++pos);
// Put the address value into the comment.
comment.Printf("0x%*.*llx ", addr_nibble_size, addr_nibble_size, operand_value);
// And the original token string into the operands.
// llvm::StringRef Str(pos - 1);
// RStrip(Str, '\n');
// operands.PutCString(Str.str().c_str());
AddSymbolicInfo (&exe_ctx, comment, operand_value, GetAddress());
}
}
// END of workaround.
m_comment.swap (comment.GetString());
}
}
bool
InstructionLLVM::DoesBranch() const
{
return EDInstIsBranch(m_inst);
}
size_t
InstructionLLVM::Decode (const Disassembler &disassembler,
const lldb_private::DataExtractor &data,
uint32_t data_offset)
{
if (EDCreateInsts(&m_inst, 1, m_disassembler, DataExtractorByteReader, data_offset, (void*)(&data)))
{
const int byte_size = EDInstByteSize(m_inst);
uint32_t offset = data_offset;
// Make a copy of the opcode in m_opcode
switch (disassembler.GetArchitecture().GetMachine())
{
case llvm::Triple::x86:
case llvm::Triple::x86_64:
m_opcode.SetOpcodeBytes (data.PeekData (data_offset, byte_size), byte_size);
break;
case llvm::Triple::arm:
case llvm::Triple::thumb:
switch (byte_size)
{
case 2:
m_opcode.SetOpcode16 (data.GetU16 (&offset));
break;
case 4:
{
if (GetAddressClass() == eAddressClassCodeAlternateISA)
{
// If it is a 32-bit THUMB instruction, we need to swap the upper & lower halves.
uint32_t orig_bytes = data.GetU32 (&offset);
uint16_t upper_bits = (orig_bytes >> 16) & ((1u << 16) - 1);
uint16_t lower_bits = orig_bytes & ((1u << 16) - 1);
uint32_t swapped = (lower_bits << 16) | upper_bits;
m_opcode.SetOpcode32 (swapped);
}
else
m_opcode.SetOpcode32 (data.GetU32 (&offset));
}
break;
default:
assert (!"Invalid ARM opcode size");
break;
}
break;
default:
assert (!"This shouldn't happen since we control the architecture we allow DisassemblerLLVM to be created for");
break;
}
return byte_size;
}
else
return 0;
}
static inline EDAssemblySyntax_t
SyntaxForArchSpec (const ArchSpec &arch)
{
switch (arch.GetMachine ())
{
case llvm::Triple::x86:
case llvm::Triple::x86_64:
return kEDAssemblySyntaxX86ATT;
case llvm::Triple::arm:
case llvm::Triple::thumb:
return kEDAssemblySyntaxARMUAL;
default:
break;
}
return (EDAssemblySyntax_t)0; // default
}
Disassembler *
DisassemblerLLVM::CreateInstance(const ArchSpec &arch)
{
std::auto_ptr<DisassemblerLLVM> disasm_ap (new DisassemblerLLVM(arch));
if (disasm_ap.get() && disasm_ap->IsValid())
return disasm_ap.release();
return NULL;
}
DisassemblerLLVM::DisassemblerLLVM(const ArchSpec &arch) :
Disassembler (arch),
m_disassembler (NULL),
m_disassembler_thumb (NULL) // For ARM only
{
// Initialize the LLVM objects needed to use the disassembler.
static struct InitializeLLVM {
InitializeLLVM() {
llvm::InitializeAllTargetInfos();
llvm::InitializeAllTargetMCs();
llvm::InitializeAllAsmParsers();
llvm::InitializeAllDisassemblers();
}
} InitializeLLVM;
const std::string &arch_triple = arch.GetTriple().str();
if (!arch_triple.empty())
{
if (EDGetDisassembler(&m_disassembler, arch_triple.c_str(), SyntaxForArchSpec (arch)))
m_disassembler = NULL;
llvm::Triple::ArchType llvm_arch = arch.GetTriple().getArch();
// Don't have the lldb::Triple::thumb architecture here. If someone specifies
// "thumb" as the architecture, we want a thumb only disassembler. But if any
// architecture starting with "arm" if specified, we want to auto detect the
// arm/thumb code automatically using the AddressClass from section offset
// addresses.
if (llvm_arch == llvm::Triple::arm)
{
if (EDGetDisassembler(&m_disassembler_thumb, "thumbv7-apple-darwin", kEDAssemblySyntaxARMUAL))
m_disassembler_thumb = NULL;
}
}
}
DisassemblerLLVM::~DisassemblerLLVM()
{
}
size_t
DisassemblerLLVM::DecodeInstructions
(
const Address &base_addr,
const DataExtractor& data,
uint32_t data_offset,
uint32_t num_instructions,
bool append
)
{
if (m_disassembler == NULL)
return 0;
size_t total_inst_byte_size = 0;
if (!append)
m_instruction_list.Clear();
while (data.ValidOffset(data_offset) && num_instructions)
{
Address inst_addr (base_addr);
inst_addr.Slide(data_offset);
bool use_thumb = false;
// If we have a thumb disassembler, then we have an ARM architecture
// so we need to check what the instruction address class is to make
// sure we shouldn't be disassembling as thumb...
AddressClass inst_address_class = eAddressClassInvalid;
if (m_disassembler_thumb)
{
inst_address_class = inst_addr.GetAddressClass ();
if (inst_address_class == eAddressClassCodeAlternateISA)
use_thumb = true;
}
InstructionSP inst_sp (new InstructionLLVM (inst_addr,
inst_address_class,
use_thumb ? m_disassembler_thumb : m_disassembler,
use_thumb ? llvm::Triple::thumb : m_arch.GetMachine()));
size_t inst_byte_size = inst_sp->Decode (*this, data, data_offset);
if (inst_byte_size == 0)
break;
m_instruction_list.Append (inst_sp);
total_inst_byte_size += inst_byte_size;
data_offset += inst_byte_size;
num_instructions--;
}
return total_inst_byte_size;
}
void
DisassemblerLLVM::Initialize()
{
PluginManager::RegisterPlugin (GetPluginNameStatic(),
GetPluginDescriptionStatic(),
CreateInstance);
}
void
DisassemblerLLVM::Terminate()
{
PluginManager::UnregisterPlugin (CreateInstance);
}
const char *
DisassemblerLLVM::GetPluginNameStatic()
{
return "llvm";
}
const char *
DisassemblerLLVM::GetPluginDescriptionStatic()
{
return "Disassembler that uses LLVM opcode tables to disassemble i386, x86_64 and ARM.";
}
//------------------------------------------------------------------
// PluginInterface protocol
//------------------------------------------------------------------
const char *
DisassemblerLLVM::GetPluginName()
{
return "DisassemblerLLVM";
}
const char *
DisassemblerLLVM::GetShortPluginName()
{
return GetPluginNameStatic();
}
uint32_t
DisassemblerLLVM::GetPluginVersion()
{
return 1;
}