lldb/source/Expression/UtilityFunction.cpp

   1 //===-- UtilityFunction.cpp -----------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include <cstdio>
  10 #include <sys/types.h>
  11
  12 #include "lldb/Core/Module.h"
  13 #include "lldb/Expression/DiagnosticManager.h"
  14 #include "lldb/Expression/FunctionCaller.h"
  15 #include "lldb/Expression/IRExecutionUnit.h"
  16 #include "lldb/Expression/UtilityFunction.h"
  17 #include "lldb/Host/Host.h"
  18 #include "lldb/Target/ExecutionContext.h"
  19 #include "lldb/Target/Process.h"
  20 #include "lldb/Target/Target.h"
  21 #include "lldb/Utility/ConstString.h"
  22 #include "lldb/Utility/Log.h"
  23 #include "lldb/Utility/State.h"
  24 #include "lldb/Utility/Stream.h"
  25
  26 using namespace lldb_private;
  27 using namespace lldb;
  28
  29 char UtilityFunction::ID;
  30
  31 /// Constructor
  32 ///
  33 /// \param[in] text
  34 ///     The text of the function.  Must be a full translation unit.
  35 ///
  36 /// \param[in] name
  37 ///     The name of the function, as used in the text.
  38 UtilityFunction::UtilityFunction(ExecutionContextScope &exe_scope,
  39                                  std::string text, std::string name,
  40                                  bool enable_debugging)
  41     : Expression(exe_scope), m_execution_unit_sp(), m_jit_module_wp(),
  42       m_function_text(std::move(text)), m_function_name(std::move(name)) {}
  43
  44 UtilityFunction::~UtilityFunction() {
  45   lldb::ProcessSP process_sp(m_jit_process_wp.lock());
  46   if (process_sp) {
  47     lldb::ModuleSP jit_module_sp(m_jit_module_wp.lock());
  48     if (jit_module_sp)
  49       process_sp->GetTarget().GetImages().Remove(jit_module_sp);
  50   }
  51 }
  52
  53 // FIXME: We should check that every time this is called it is called with the
  54 // same return type & arguments...
  55
  56 FunctionCaller *UtilityFunction::MakeFunctionCaller(
  57     const CompilerType &return_type, const ValueList &arg_value_list,
  58     lldb::ThreadSP thread_to_use_sp, Status &error) {
  59   if (m_caller_up)
  60     return m_caller_up.get();
  61
  62   ProcessSP process_sp = m_jit_process_wp.lock();
  63   if (!process_sp) {
  64     error = Status::FromErrorString(
  65         "Can't make a function caller without a process.");
  66     return nullptr;
  67   }
  68   // Since we might need to allocate memory and maybe call code to make
  69   // the caller, we need to be stopped.
  70   if (process_sp->GetState() != lldb::eStateStopped) {
  71     error = Status::FromErrorStringWithFormatv(
  72         "Can't make a function caller while the process is {0}: the process "
  73         "must be stopped to allocate memory.",
  74         StateAsCString(process_sp->GetState()));
  75     return nullptr;
  76   }
  77
  78   Address impl_code_address;
  79   impl_code_address.SetOffset(StartAddress());
  80   std::string name(m_function_name);
  81   name.append("-caller");
  82
  83   m_caller_up.reset(process_sp->GetTarget().GetFunctionCallerForLanguage(
  84       Language().AsLanguageType(), return_type, impl_code_address,
  85       arg_value_list, name.c_str(), error));
  86   if (error.Fail())
  87     return nullptr;
  88
  89   if (m_caller_up) {
  90     DiagnosticManager diagnostics;
  91
  92     unsigned num_errors =
  93         m_caller_up->CompileFunction(thread_to_use_sp, diagnostics);
  94     if (num_errors) {
  95       error = Status::FromError(diagnostics.GetAsError(
  96           lldb::eExpressionParseError,
  97           "Error compiling " + m_function_name + " caller function:"));
  98
  99       m_caller_up.reset();
 100       return nullptr;
 101     }
 102
 103     diagnostics.Clear();
 104     ExecutionContext exe_ctx(process_sp);
 105
 106     if (!m_caller_up->WriteFunctionWrapper(exe_ctx, diagnostics)) {
 107       error = Status::FromError(diagnostics.GetAsError(
 108           lldb::eExpressionSetupError,
 109           "Error inserting " + m_function_name + " caller function:"));
 110       m_caller_up.reset();
 111       return nullptr;
 112     }
 113   }
 114   return m_caller_up.get();
 115 }