xref: /freebsd/contrib/llvm-project/lldb/source/Expression/UtilityFunction.cpp (revision aa1a8ff2d6dbc51ef058f46f3db5a8bb77967145)
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.SetErrorString("Can't make a function caller without a process.");
65     return nullptr;
66   }
67   // Since we might need to allocate memory and maybe call code to make
68   // the caller, we need to be stopped.
69   if (process_sp->GetState() != lldb::eStateStopped) {
70     error.SetErrorStringWithFormatv(
71         "Can't make a function caller while the process is {0}: the process "
72         "must be stopped to allocate memory.",
73         StateAsCString(process_sp->GetState()));
74     return nullptr;
75   }
76 
77   Address impl_code_address;
78   impl_code_address.SetOffset(StartAddress());
79   std::string name(m_function_name);
80   name.append("-caller");
81 
82   m_caller_up.reset(process_sp->GetTarget().GetFunctionCallerForLanguage(
83       Language(), return_type, impl_code_address, arg_value_list, name.c_str(),
84       error));
85   if (error.Fail()) {
86 
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.SetErrorStringWithFormat(
96           "Error compiling %s caller function: \"%s\".",
97           m_function_name.c_str(), diagnostics.GetString().c_str());
98       m_caller_up.reset();
99       return nullptr;
100     }
101 
102     diagnostics.Clear();
103     ExecutionContext exe_ctx(process_sp);
104 
105     if (!m_caller_up->WriteFunctionWrapper(exe_ctx, diagnostics)) {
106       error.SetErrorStringWithFormat(
107           "Error inserting caller function for %s: \"%s\".",
108           m_function_name.c_str(), diagnostics.GetString().c_str());
109       m_caller_up.reset();
110       return nullptr;
111     }
112   }
113   return m_caller_up.get();
114 }
115