C++ Process::AllocateMemory方法代码示例

bool
RecordingMemoryManager::CommitAllocations (Process &process)
{
    bool ret = true;

    for (AllocationList::iterator ai = m_allocations.begin(), ae = m_allocations.end();
            ai != ae;
            ++ai)
    {
        if (ai->m_allocated)
            continue;

        lldb_private::Error err;

        size_t allocation_size = (ai->m_size ? ai->m_size : 1) + ai->m_alignment - 1;

        if (allocation_size == 0)
            allocation_size = 1;

        ai->m_remote_allocation = process.AllocateMemory(
                                      allocation_size,
                                      ai->m_executable ? (lldb::ePermissionsReadable | lldb::ePermissionsExecutable)
                                      : (lldb::ePermissionsReadable | lldb::ePermissionsWritable),
                                      err);

        uint64_t mask = ai->m_alignment - 1;

        ai->m_remote_start = (ai->m_remote_allocation + mask) & (~mask);

        if (!err.Success())
        {
            ret = false;
            break;
        }

        ai->m_allocated = true;

        if (m_log)
        {
            m_log->Printf("RecordingMemoryManager::CommitAllocations() committed an allocation");
            ai->dump(m_log);
        }
    }

    if (!ret)
    {
        for (AllocationList::iterator ai = m_allocations.end(), ae = m_allocations.end();
                ai != ae;
                ++ai)
        {
            if (ai->m_allocated)
                process.DeallocateMemory(ai->m_remote_start);
        }
    }

    return ret;
}

bool
ClangFunction::WriteFunctionArguments (ExecutionContext &exe_ctx, 
                                       lldb::addr_t &args_addr_ref, 
                                       Address function_address, 
                                       ValueList &arg_values, 
                                       Stream &errors)
{
    // All the information to reconstruct the struct is provided by the
    // StructExtractor.
    if (!m_struct_valid)
    {
        errors.Printf("Argument information was not correctly parsed, so the function cannot be called.");
        return false;
    }
        
    Error error;
    using namespace clang;
    ExecutionResults return_value = eExecutionSetupError;

    Process *process = exe_ctx.GetProcessPtr();

    if (process == NULL)
        return return_value;

    if (process != m_jit_process_sp.get())
        return false;
                
    if (args_addr_ref == LLDB_INVALID_ADDRESS)
    {
        args_addr_ref = process->AllocateMemory(m_struct_size, lldb::ePermissionsReadable|lldb::ePermissionsWritable, error);
        if (args_addr_ref == LLDB_INVALID_ADDRESS)
            return false;
        m_wrapper_args_addrs.push_back (args_addr_ref);
    } 
    else 
    {
        // Make sure this is an address that we've already handed out.
        if (find (m_wrapper_args_addrs.begin(), m_wrapper_args_addrs.end(), args_addr_ref) == m_wrapper_args_addrs.end())
        {
            return false;
        }
    }

    // TODO: verify fun_addr needs to be a callable address
    Scalar fun_addr (function_address.GetCallableLoadAddress(exe_ctx.GetTargetPtr()));
    int first_offset = m_member_offsets[0];
    process->WriteScalarToMemory(args_addr_ref + first_offset, fun_addr, process->GetAddressByteSize(), error);

    // FIXME: We will need to extend this for Variadic functions.

    Error value_error;
    
    size_t num_args = arg_values.GetSize();
    if (num_args != m_arg_values.GetSize())
    {
        errors.Printf ("Wrong number of arguments - was: %lu should be: %lu", num_args, m_arg_values.GetSize());
        return false;
    }
    
    for (size_t i = 0; i < num_args; i++)
    {
        // FIXME: We should sanity check sizes.

        int offset = m_member_offsets[i+1]; // Clang sizes are in bytes.
        Value *arg_value = arg_values.GetValueAtIndex(i);
        
        // FIXME: For now just do scalars:
        
        // Special case: if it's a pointer, don't do anything (the ABI supports passing cstrings)
        
        if (arg_value->GetValueType() == Value::eValueTypeHostAddress &&
            arg_value->GetContextType() == Value::eContextTypeClangType &&
            ClangASTContext::IsPointerType(arg_value->GetClangType()))
            continue;
        
        const Scalar &arg_scalar = arg_value->ResolveValue(&exe_ctx, m_clang_ast_context->getASTContext());

        if (!process->WriteScalarToMemory(args_addr_ref + offset, arg_scalar, arg_scalar.GetByteSize(), error))
            return false;
    }

    return true;
}

//.........这里部分代码省略.........
        return err;
    }
    
    m_jitted_functions.push_back (ClangExpressionParser::JittedFunction(function_name.c_str(), (lldb::addr_t)fun_ptr));
    

    Process *process = exe_ctx.GetProcessPtr();
    if (process == NULL)
    {
        err.SetErrorToGenericError();
        err.SetErrorString("Couldn't write the JIT compiled code into the target because there is no target");
        return err;
    }
    
    // Look over the regions allocated for the function compiled.  The JIT
    // tries to allocate the functions & stubs close together, so we should try to
    // write them that way too...
    // For now I only write functions with no stubs, globals, exception tables,
    // etc.  So I only need to write the functions.
    
    size_t alloc_size = 0;
    
    std::map<uint8_t *, uint8_t *>::iterator fun_pos = jit_memory_manager->m_functions.begin();
    std::map<uint8_t *, uint8_t *>::iterator fun_end = jit_memory_manager->m_functions.end();

    for (; fun_pos != fun_end; ++fun_pos)
    {
        size_t mem_size = fun_pos->second - fun_pos->first;
        if (log)
            log->Printf ("JIT memory: [%p - %p) size = %zu", fun_pos->first, fun_pos->second, mem_size);
        alloc_size += mem_size;
    }
    
    Error alloc_error;
    func_allocation_addr = process->AllocateMemory (alloc_size, 
                                                                lldb::ePermissionsReadable|lldb::ePermissionsExecutable, 
                                                                alloc_error);
    
    if (func_allocation_addr == LLDB_INVALID_ADDRESS)
    {
        err.SetErrorToGenericError();
        err.SetErrorStringWithFormat("Couldn't allocate memory for the JITted function: %s", alloc_error.AsCString("unknown error"));
        return err;
    }
    
    lldb::addr_t cursor = func_allocation_addr;
        
    for (fun_pos = jit_memory_manager->m_functions.begin(); fun_pos != fun_end; fun_pos++)
    {
        lldb::addr_t lstart = (lldb::addr_t) (*fun_pos).first;
        lldb::addr_t lend = (lldb::addr_t) (*fun_pos).second;
        size_t size = lend - lstart;
        
        Error write_error;
        
        if (process->WriteMemory(cursor, (void *) lstart, size, write_error) != size)
        {
            err.SetErrorToGenericError();
            err.SetErrorStringWithFormat("Couldn't copy JIT code for function into the target: %s", write_error.AsCString("unknown error"));
            return err;
        }
            
        jit_memory_manager->AddToLocalToRemoteMap (lstart, size, cursor);
        cursor += size;
    }
    
    std::vector<JittedFunction>::iterator pos, end = m_jitted_functions.end();
    
    for (pos = m_jitted_functions.begin(); pos != end; pos++)
    {
        (*pos).m_remote_addr = jit_memory_manager->GetRemoteAddressForLocal ((*pos).m_local_addr);
    
        if (!(*pos).m_name.compare(function_name.c_str()))
        {
            func_end = jit_memory_manager->GetRemoteRangeForLocal ((*pos).m_local_addr).second;
            func_addr = (*pos).m_remote_addr;
        }
    }
    
    if (log)
    {
        log->Printf("Code can be run in the target.");
        
        StreamString disassembly_stream;
        
        Error err = DisassembleFunction(disassembly_stream, exe_ctx, jit_memory_manager);
        
        if (!err.Success())
        {
            log->Printf("Couldn't disassemble function : %s", err.AsCString("unknown error"));
        }
        else
        {
            log->Printf("Function disassembly:\n%s", disassembly_stream.GetData());
        }
    }
    
    err.Clear();
    return err;
}

bool FunctionCaller::WriteFunctionArguments(
    ExecutionContext &exe_ctx, lldb::addr_t &args_addr_ref,
    ValueList &arg_values, DiagnosticManager &diagnostic_manager) {
  // All the information to reconstruct the struct is provided by the
  // StructExtractor.
  if (!m_struct_valid) {
    diagnostic_manager.PutString(eDiagnosticSeverityError,
                                 "Argument information was not correctly "
                                 "parsed, so the function cannot be called.");
    return false;
  }

  Status error;
  lldb::ExpressionResults return_value = lldb::eExpressionSetupError;

  Process *process = exe_ctx.GetProcessPtr();

  if (process == NULL)
    return return_value;

  lldb::ProcessSP jit_process_sp(m_jit_process_wp.lock());

  if (process != jit_process_sp.get())
    return false;

  if (args_addr_ref == LLDB_INVALID_ADDRESS) {
    args_addr_ref = process->AllocateMemory(
        m_struct_size, lldb::ePermissionsReadable | lldb::ePermissionsWritable,
        error);
    if (args_addr_ref == LLDB_INVALID_ADDRESS)
      return false;
    m_wrapper_args_addrs.push_back(args_addr_ref);
  } else {
    // Make sure this is an address that we've already handed out.
    if (find(m_wrapper_args_addrs.begin(), m_wrapper_args_addrs.end(),
             args_addr_ref) == m_wrapper_args_addrs.end()) {
      return false;
    }
  }

  // TODO: verify fun_addr needs to be a callable address
  Scalar fun_addr(
      m_function_addr.GetCallableLoadAddress(exe_ctx.GetTargetPtr()));
  uint64_t first_offset = m_member_offsets[0];
  process->WriteScalarToMemory(args_addr_ref + first_offset, fun_addr,
                               process->GetAddressByteSize(), error);

  // FIXME: We will need to extend this for Variadic functions.

  Status value_error;

  size_t num_args = arg_values.GetSize();
  if (num_args != m_arg_values.GetSize()) {
    diagnostic_manager.Printf(
        eDiagnosticSeverityError,
        "Wrong number of arguments - was: %" PRIu64 " should be: %" PRIu64 "",
        (uint64_t)num_args, (uint64_t)m_arg_values.GetSize());
    return false;
  }

  for (size_t i = 0; i < num_args; i++) {
    // FIXME: We should sanity check sizes.

    uint64_t offset = m_member_offsets[i + 1]; // Clang sizes are in bytes.
    Value *arg_value = arg_values.GetValueAtIndex(i);

    // FIXME: For now just do scalars:

    // Special case: if it's a pointer, don't do anything (the ABI supports
    // passing cstrings)

    if (arg_value->GetValueType() == Value::eValueTypeHostAddress &&
        arg_value->GetContextType() == Value::eContextTypeInvalid &&
        arg_value->GetCompilerType().IsPointerType())
      continue;

    const Scalar &arg_scalar = arg_value->ResolveValue(&exe_ctx);

    if (!process->WriteScalarToMemory(args_addr_ref + offset, arg_scalar,
                                      arg_scalar.GetByteSize(), error))
      return false;
  }

  return true;
}