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
25using namespace llvm;
26using namespace clang;
27using namespace lldb_private;
28
29ASTStructExtractor::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>(Val: passthrough);
39}
40
41ASTStructExtractor::~ASTStructExtractor() = default;
42
43void ASTStructExtractor::Initialize(ASTContext &Context) {
44 m_ast_context = &Context;
45
46 if (m_passthrough)
47 m_passthrough->Initialize(Context);
48}
49
50void 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>(Val: 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>(Val: 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>(Val: 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(D: 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(FieldNo: 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 x: struct_layout->getFieldOffset(FieldNo: field_index) / 8);
106 }
107
108 m_function.m_struct_valid = true;
109}
110
111void ASTStructExtractor::ExtractFromTopLevelDecl(Decl *D) {
112 LinkageSpecDecl *linkage_spec_decl = dyn_cast<LinkageSpecDecl>(Val: 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(D: *decl_iterator);
120 }
121 }
122
123 FunctionDecl *function_decl = dyn_cast<FunctionDecl>(Val: D);
124
125 if (m_ast_context && function_decl &&
126 m_function.m_wrapper_function_name == function_decl->getNameAsString()) {
127 ExtractFromFunctionDecl(F: function_decl);
128 }
129}
130
131bool ASTStructExtractor::HandleTopLevelDecl(DeclGroupRef D) {
132 DeclGroupRef::iterator decl_iterator;
133
134 for (decl_iterator = D.begin(); decl_iterator != D.end(); ++decl_iterator) {
135 Decl *decl = *decl_iterator;
136
137 ExtractFromTopLevelDecl(D: decl);
138 }
139
140 if (m_passthrough)
141 return m_passthrough->HandleTopLevelDecl(D);
142 return true;
143}
144
145void ASTStructExtractor::HandleTranslationUnit(ASTContext &Ctx) {
146 if (m_passthrough)
147 m_passthrough->HandleTranslationUnit(Ctx);
148}
149
150void ASTStructExtractor::HandleTagDeclDefinition(TagDecl *D) {
151 if (m_passthrough)
152 m_passthrough->HandleTagDeclDefinition(D);
153}
154
155void ASTStructExtractor::CompleteTentativeDefinition(VarDecl *D) {
156 if (m_passthrough)
157 m_passthrough->CompleteTentativeDefinition(D);
158}
159
160void ASTStructExtractor::HandleVTable(CXXRecordDecl *RD) {
161 if (m_passthrough)
162 m_passthrough->HandleVTable(RD);
163}
164
165void ASTStructExtractor::PrintStats() {
166 if (m_passthrough)
167 m_passthrough->PrintStats();
168}
169
170void ASTStructExtractor::InitializeSema(Sema &S) {
171 m_sema = &S;
172
173 if (m_passthrough_sema)
174 m_passthrough_sema->InitializeSema(S);
175}
176
177void ASTStructExtractor::ForgetSema() {
178 m_sema = nullptr;
179
180 if (m_passthrough_sema)
181 m_passthrough_sema->ForgetSema();
182}
183

source code of lldb/source/Plugins/ExpressionParser/Clang/ASTStructExtractor.cpp