1 //===-- ClangPersistentVariables.cpp ----------------------------*- C++ -*-===//
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 "ClangPersistentVariables.h"
10 
11 #include "lldb/Core/Value.h"
12 #include "lldb/Symbol/ClangASTContext.h"
13 #include "lldb/Target/Target.h"
14 #include "lldb/Utility/DataExtractor.h"
15 #include "lldb/Utility/Log.h"
16 #include "lldb/Utility/StreamString.h"
17 
18 #include "clang/AST/Decl.h"
19 
20 #include "llvm/ADT/StringMap.h"
21 
22 using namespace lldb;
23 using namespace lldb_private;
24 
25 ClangPersistentVariables::ClangPersistentVariables()
26     : lldb_private::PersistentExpressionState(LLVMCastKind::eKindClang) {}
27 
28 ExpressionVariableSP ClangPersistentVariables::CreatePersistentVariable(
29     const lldb::ValueObjectSP &valobj_sp) {
30   return AddNewlyConstructedVariable(new ClangExpressionVariable(valobj_sp));
31 }
32 
33 ExpressionVariableSP ClangPersistentVariables::CreatePersistentVariable(
34     ExecutionContextScope *exe_scope, ConstString name,
35     const CompilerType &compiler_type, lldb::ByteOrder byte_order,
36     uint32_t addr_byte_size) {
37   return AddNewlyConstructedVariable(new ClangExpressionVariable(
38       exe_scope, name, compiler_type, byte_order, addr_byte_size));
39 }
40 
41 void ClangPersistentVariables::RemovePersistentVariable(
42     lldb::ExpressionVariableSP variable) {
43   RemoveVariable(variable);
44 
45   // Check if the removed variable was the last one that was created. If yes,
46   // reuse the variable id for the next variable.
47 
48   // Nothing to do if we have not assigned a variable id so far.
49   if (m_next_persistent_variable_id == 0)
50     return;
51 
52   llvm::StringRef name = variable->GetName().GetStringRef();
53   // Remove the prefix from the variable that only the indes is left.
54   if (!name.consume_front(GetPersistentVariablePrefix(false)))
55     return;
56 
57   // Check if the variable contained a variable id.
58   uint32_t variable_id;
59   if (name.getAsInteger(10, variable_id))
60     return;
61   // If it's the most recent variable id that was assigned, make sure that this
62   // variable id will be used for the next persistent variable.
63   if (variable_id == m_next_persistent_variable_id - 1)
64     m_next_persistent_variable_id--;
65 }
66 
67 llvm::Optional<CompilerType>
68 ClangPersistentVariables::GetCompilerTypeFromPersistentDecl(
69     ConstString type_name) {
70   PersistentDecl p = m_persistent_decls.lookup(type_name.GetCString());
71 
72   if (p.m_decl == nullptr)
73     return llvm::None;
74 
75   if (clang::TypeDecl *tdecl = llvm::dyn_cast<clang::TypeDecl>(p.m_decl)) {
76     opaque_compiler_type_t t = static_cast<opaque_compiler_type_t>(
77         const_cast<clang::Type *>(tdecl->getTypeForDecl()));
78     return CompilerType(p.m_context, t);
79   }
80   return llvm::None;
81 }
82 
83 void ClangPersistentVariables::RegisterPersistentDecl(ConstString name,
84                                                       clang::NamedDecl *decl,
85                                                       ClangASTContext *ctx) {
86   PersistentDecl p = {decl, ctx};
87   m_persistent_decls.insert(std::make_pair(name.GetCString(), p));
88 
89   if (clang::EnumDecl *enum_decl = llvm::dyn_cast<clang::EnumDecl>(decl)) {
90     for (clang::EnumConstantDecl *enumerator_decl : enum_decl->enumerators()) {
91       p = {enumerator_decl, ctx};
92       m_persistent_decls.insert(std::make_pair(
93           ConstString(enumerator_decl->getNameAsString()).GetCString(), p));
94     }
95   }
96 }
97 
98 clang::NamedDecl *
99 ClangPersistentVariables::GetPersistentDecl(ConstString name) {
100   return m_persistent_decls.lookup(name.GetCString()).m_decl;
101 }
102