1 //===-- ASTStructExtractor.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 "ASTStructExtractor.h"
10
11 #include "lldb/Utility/Log.h"
12 #include "clang/AST/ASTContext.h"
13 #include "clang/AST/Decl.h"
14 #include "clang/AST/DeclCXX.h"
15 #include "clang/AST/DeclGroup.h"
16 #include "clang/AST/Expr.h"
17 #include "clang/AST/RecordLayout.h"
18 #include "clang/AST/Stmt.h"
19 #include "clang/Parse/Parser.h"
20 #include "clang/Sema/Sema.h"
21 #include "llvm/Support/Casting.h"
22 #include "llvm/Support/raw_ostream.h"
23 #include <cstdlib>
24
25 using namespace llvm;
26 using namespace clang;
27 using namespace lldb_private;
28
ASTStructExtractor(ASTConsumer * passthrough,const char * struct_name,ClangFunctionCaller & function)29 ASTStructExtractor::ASTStructExtractor(ASTConsumer *passthrough,
30 const char *struct_name,
31 ClangFunctionCaller &function)
32 : m_ast_context(nullptr), m_passthrough(passthrough),
33 m_passthrough_sema(nullptr), m_sema(nullptr), m_function(function),
34 m_struct_name(struct_name) {
35 if (!m_passthrough)
36 return;
37
38 m_passthrough_sema = dyn_cast<SemaConsumer>(passthrough);
39 }
40
41 ASTStructExtractor::~ASTStructExtractor() = default;
42
Initialize(ASTContext & Context)43 void ASTStructExtractor::Initialize(ASTContext &Context) {
44 m_ast_context = &Context;
45
46 if (m_passthrough)
47 m_passthrough->Initialize(Context);
48 }
49
ExtractFromFunctionDecl(FunctionDecl * F)50 void ASTStructExtractor::ExtractFromFunctionDecl(FunctionDecl *F) {
51 if (!F->hasBody())
52 return;
53
54 Stmt *body_stmt = F->getBody();
55 CompoundStmt *body_compound_stmt = dyn_cast<CompoundStmt>(body_stmt);
56
57 if (!body_compound_stmt)
58 return; // do we have to handle this?
59
60 RecordDecl *struct_decl = nullptr;
61
62 StringRef desired_name(m_struct_name);
63
64 for (CompoundStmt::const_body_iterator bi = body_compound_stmt->body_begin(),
65 be = body_compound_stmt->body_end();
66 bi != be; ++bi) {
67 Stmt *curr_stmt = *bi;
68 DeclStmt *curr_decl_stmt = dyn_cast<DeclStmt>(curr_stmt);
69 if (!curr_decl_stmt)
70 continue;
71 DeclGroupRef decl_group = curr_decl_stmt->getDeclGroup();
72 for (Decl *candidate_decl : decl_group) {
73 RecordDecl *candidate_record_decl = dyn_cast<RecordDecl>(candidate_decl);
74 if (!candidate_record_decl)
75 continue;
76 if (candidate_record_decl->getName() == desired_name) {
77 struct_decl = candidate_record_decl;
78 break;
79 }
80 }
81 if (struct_decl)
82 break;
83 }
84
85 if (!struct_decl)
86 return;
87
88 const ASTRecordLayout *struct_layout(
89 &m_ast_context->getASTRecordLayout(struct_decl));
90
91 if (!struct_layout)
92 return;
93
94 m_function.m_struct_size =
95 struct_layout->getSize()
96 .getQuantity(); // TODO Store m_struct_size as CharUnits
97 m_function.m_return_offset =
98 struct_layout->getFieldOffset(struct_layout->getFieldCount() - 1) / 8;
99 m_function.m_return_size =
100 struct_layout->getDataSize().getQuantity() - m_function.m_return_offset;
101
102 for (unsigned field_index = 0, num_fields = struct_layout->getFieldCount();
103 field_index < num_fields; ++field_index) {
104 m_function.m_member_offsets.push_back(
105 struct_layout->getFieldOffset(field_index) / 8);
106 }
107
108 m_function.m_struct_valid = true;
109 }
110
ExtractFromTopLevelDecl(Decl * D)111 void ASTStructExtractor::ExtractFromTopLevelDecl(Decl *D) {
112 LinkageSpecDecl *linkage_spec_decl = dyn_cast<LinkageSpecDecl>(D);
113
114 if (linkage_spec_decl) {
115 RecordDecl::decl_iterator decl_iterator;
116
117 for (decl_iterator = linkage_spec_decl->decls_begin();
118 decl_iterator != linkage_spec_decl->decls_end(); ++decl_iterator) {
119 ExtractFromTopLevelDecl(*decl_iterator);
120 }
121 }
122
123 FunctionDecl *function_decl = dyn_cast<FunctionDecl>(D);
124
125 if (m_ast_context && function_decl &&
126 !m_function.m_wrapper_function_name.compare(
127 function_decl->getNameAsString())) {
128 ExtractFromFunctionDecl(function_decl);
129 }
130 }
131
HandleTopLevelDecl(DeclGroupRef D)132 bool ASTStructExtractor::HandleTopLevelDecl(DeclGroupRef D) {
133 DeclGroupRef::iterator decl_iterator;
134
135 for (decl_iterator = D.begin(); decl_iterator != D.end(); ++decl_iterator) {
136 Decl *decl = *decl_iterator;
137
138 ExtractFromTopLevelDecl(decl);
139 }
140
141 if (m_passthrough)
142 return m_passthrough->HandleTopLevelDecl(D);
143 return true;
144 }
145
HandleTranslationUnit(ASTContext & Ctx)146 void ASTStructExtractor::HandleTranslationUnit(ASTContext &Ctx) {
147 if (m_passthrough)
148 m_passthrough->HandleTranslationUnit(Ctx);
149 }
150
HandleTagDeclDefinition(TagDecl * D)151 void ASTStructExtractor::HandleTagDeclDefinition(TagDecl *D) {
152 if (m_passthrough)
153 m_passthrough->HandleTagDeclDefinition(D);
154 }
155
CompleteTentativeDefinition(VarDecl * D)156 void ASTStructExtractor::CompleteTentativeDefinition(VarDecl *D) {
157 if (m_passthrough)
158 m_passthrough->CompleteTentativeDefinition(D);
159 }
160
HandleVTable(CXXRecordDecl * RD)161 void ASTStructExtractor::HandleVTable(CXXRecordDecl *RD) {
162 if (m_passthrough)
163 m_passthrough->HandleVTable(RD);
164 }
165
PrintStats()166 void ASTStructExtractor::PrintStats() {
167 if (m_passthrough)
168 m_passthrough->PrintStats();
169 }
170
InitializeSema(Sema & S)171 void ASTStructExtractor::InitializeSema(Sema &S) {
172 m_sema = &S;
173
174 if (m_passthrough_sema)
175 m_passthrough_sema->InitializeSema(S);
176 }
177
ForgetSema()178 void ASTStructExtractor::ForgetSema() {
179 m_sema = nullptr;
180
181 if (m_passthrough_sema)
182 m_passthrough_sema->ForgetSema();
183 }
184