Files
llvm/lldb/source/API/SBInstruction.cpp
Greg Clayton b9556acc9e SBFrame is now threadsafe using some extra tricks. One issue is that stack
frames might go away (the object itself, not the actual logical frame) when
we are single stepping due to the way we currently sometimes end up flushing
frames when stepping in/out/over. They later will come back to life 
represented by another object yet they have the same StackID. Now when you get
a lldb::SBFrame object, it will track the frame it is initialized with until 
the thread goes away or the StackID no longer exists in the stack for the 
thread it was created on. It uses a weak_ptr to both the frame and thread and
also stores the StackID. These three items allow us to determine when the
stack frame object has gone away (the weak_ptr will be NULL) and allows us to
find the correct frame again. In our test suite we had such cases where we
were just getting lucky when something like this happened:

1 - stop at breakpoint
2 - get first frame in thread where we stopped
3 - run an expression that causes the program to JIT and run code
4 - run more expressions on the frame from step 2 which was very very luckily
    still around inside a shared pointer, yet, not part of the current 
    thread (a new stack frame object had appeared with the same stack ID and
    depth). 
    
We now avoid all such issues and properly keep up to date, or we start 
returning errors when the frame doesn't exist and always responds with
invalid answers.

Also fixed the UserSettingsController  (not going to rewrite this just yet)
so that it doesn't crash on shutdown. Using weak_ptr's came in real handy to
track when the master controller has already gone away and this allowed me to
pull out the previous NotifyOwnerIsShuttingDown() patch as it is no longer 
needed.

llvm-svn: 149231
2012-01-30 07:41:31 +00:00

250 lines
6.7 KiB
C++

//===-- SBInstruction.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/API/SBInstruction.h"
#include "lldb/API/SBAddress.h"
#include "lldb/API/SBFrame.h"
#include "lldb/API/SBInstruction.h"
#include "lldb/API/SBStream.h"
#include "lldb/API/SBTarget.h"
#include "lldb/Core/ArchSpec.h"
#include "lldb/Core/DataBufferHeap.h"
#include "lldb/Core/Disassembler.h"
#include "lldb/Core/EmulateInstruction.h"
#include "lldb/Core/StreamFile.h"
#include "lldb/Target/ExecutionContext.h"
#include "lldb/Target/StackFrame.h"
#include "lldb/Target/Target.h"
using namespace lldb;
using namespace lldb_private;
SBInstruction::SBInstruction ()
{
}
SBInstruction::SBInstruction (const lldb::InstructionSP& inst_sp) :
m_opaque_sp (inst_sp)
{
}
SBInstruction::SBInstruction(const SBInstruction &rhs) :
m_opaque_sp (rhs.m_opaque_sp)
{
}
const SBInstruction &
SBInstruction::operator = (const SBInstruction &rhs)
{
if (this != &rhs)
m_opaque_sp = rhs.m_opaque_sp;
return *this;
}
SBInstruction::~SBInstruction ()
{
}
bool
SBInstruction::IsValid()
{
return (m_opaque_sp.get() != NULL);
}
SBAddress
SBInstruction::GetAddress()
{
SBAddress sb_addr;
if (m_opaque_sp && m_opaque_sp->GetAddress().IsValid())
sb_addr.SetAddress(&m_opaque_sp->GetAddress());
return sb_addr;
}
const char *
SBInstruction::GetMnemonic(SBTarget target)
{
if (m_opaque_sp)
{
Mutex::Locker api_locker;
ExecutionContext exe_ctx;
TargetSP target_sp (target.GetSP());
if (target_sp)
{
api_locker.Reset (target_sp->GetAPIMutex().GetMutex());
target_sp->CalculateExecutionContext (exe_ctx);
exe_ctx.SetProcessSP(target_sp->GetProcessSP());
}
return m_opaque_sp->GetMnemonic(exe_ctx.GetBestExecutionContextScope());
}
return NULL;
}
const char *
SBInstruction::GetOperands(SBTarget target)
{
if (m_opaque_sp)
{
Mutex::Locker api_locker;
ExecutionContext exe_ctx;
TargetSP target_sp (target.GetSP());
if (target_sp)
{
api_locker.Reset (target_sp->GetAPIMutex().GetMutex());
target_sp->CalculateExecutionContext (exe_ctx);
exe_ctx.SetProcessSP(target_sp->GetProcessSP());
}
return m_opaque_sp->GetOperands(exe_ctx.GetBestExecutionContextScope());
}
return NULL;
}
const char *
SBInstruction::GetComment(SBTarget target)
{
if (m_opaque_sp)
{
Mutex::Locker api_locker;
ExecutionContext exe_ctx;
TargetSP target_sp (target.GetSP());
if (target_sp)
{
api_locker.Reset (target_sp->GetAPIMutex().GetMutex());
target_sp->CalculateExecutionContext (exe_ctx);
exe_ctx.SetProcessSP(target_sp->GetProcessSP());
}
return m_opaque_sp->GetComment(exe_ctx.GetBestExecutionContextScope());
}
return NULL;
}
size_t
SBInstruction::GetByteSize ()
{
if (m_opaque_sp)
return m_opaque_sp->GetOpcode().GetByteSize();
return 0;
}
SBData
SBInstruction::GetData (SBTarget target)
{
lldb::SBData sb_data;
if (m_opaque_sp)
{
const Opcode &opcode = m_opaque_sp->GetOpcode();
const void *opcode_data = opcode.GetOpcodeBytes();
const uint32_t opcode_data_size = opcode.GetByteSize();
if (opcode_data && opcode_data_size > 0)
{
ByteOrder data_byte_order = opcode.GetDataByteOrder();
TargetSP target_sp (target.GetSP());
if (data_byte_order == eByteOrderInvalid && target_sp)
data_byte_order = target_sp->GetArchitecture().GetByteOrder();
DataBufferSP data_buffer_sp (new DataBufferHeap (opcode_data, opcode_data_size));
DataExtractorSP data_extractor_sp (new DataExtractor (data_buffer_sp,
data_byte_order,
target_sp ? target_sp->GetArchitecture().GetAddressByteSize() : sizeof(void*)));
sb_data.SetOpaque (data_extractor_sp);
}
}
return sb_data;
}
bool
SBInstruction::DoesBranch ()
{
if (m_opaque_sp)
return m_opaque_sp->DoesBranch ();
return false;
}
void
SBInstruction::SetOpaque (const lldb::InstructionSP &inst_sp)
{
m_opaque_sp = inst_sp;
}
bool
SBInstruction::GetDescription (lldb::SBStream &s)
{
if (m_opaque_sp)
{
// Use the "ref()" instead of the "get()" accessor in case the SBStream
// didn't have a stream already created, one will get created...
m_opaque_sp->Dump (&s.ref(), 0, true, false, NULL, false);
return true;
}
return false;
}
void
SBInstruction::Print (FILE *out)
{
if (out == NULL)
return;
if (m_opaque_sp)
{
StreamFile out_stream (out, false);
m_opaque_sp->Dump (&out_stream, 0, true, false, NULL, false);
}
}
bool
SBInstruction::EmulateWithFrame (lldb::SBFrame &frame, uint32_t evaluate_options)
{
if (m_opaque_sp)
{
lldb::StackFrameSP frame_sp (frame.GetFrameSP());
if (frame_sp)
{
lldb_private::ExecutionContext exe_ctx;
frame_sp->CalculateExecutionContext (exe_ctx);
lldb_private::Target *target = exe_ctx.GetTargetPtr();
lldb_private::ArchSpec arch = target->GetArchitecture();
return m_opaque_sp->Emulate (arch,
evaluate_options,
(void *) frame_sp.get(),
&lldb_private::EmulateInstruction::ReadMemoryFrame,
&lldb_private::EmulateInstruction::WriteMemoryFrame,
&lldb_private::EmulateInstruction::ReadRegisterFrame,
&lldb_private::EmulateInstruction::WriteRegisterFrame);
}
}
return false;
}
bool
SBInstruction::DumpEmulation (const char *triple)
{
if (m_opaque_sp && triple)
{
lldb_private::ArchSpec arch (triple, NULL);
return m_opaque_sp->DumpEmulation (arch);
}
return false;
}
bool
SBInstruction::TestEmulation (lldb::SBStream &output_stream, const char *test_file)
{
if (!m_opaque_sp.get())
m_opaque_sp.reset (new PseudoInstruction());
return m_opaque_sp->TestEmulation (output_stream.get(), test_file);
}