xref: /llvm-project/lldb/source/Plugins/ExpressionParser/Clang/ASTStructExtractor.h (revision cdc514e4c67f268b07863bbac3d8d7e0d088186c)
14dbb271fSSean Callanan //===-- ASTStructExtractor.h ------------------------------------*- C++ -*-===//
24dbb271fSSean Callanan //
32946cd70SChandler Carruth // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
42946cd70SChandler Carruth // See https://llvm.org/LICENSE.txt for license information.
52946cd70SChandler Carruth // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
64dbb271fSSean Callanan //
74dbb271fSSean Callanan //===----------------------------------------------------------------------===//
84dbb271fSSean Callanan 
9*cdc514e4SJonas Devlieghere #ifndef LLDB_SOURCE_PLUGINS_EXPRESSIONPARSER_CLANG_ASTSTRUCTEXTRACTOR_H
10*cdc514e4SJonas Devlieghere #define LLDB_SOURCE_PLUGINS_EXPRESSIONPARSER_CLANG_ASTSTRUCTEXTRACTOR_H
114dbb271fSSean Callanan 
124dbb271fSSean Callanan #include "ClangExpressionVariable.h"
134dbb271fSSean Callanan #include "ClangFunctionCaller.h"
144dbb271fSSean Callanan 
15b9c1b51eSKate Stone #include "clang/Sema/SemaConsumer.h"
164dbb271fSSean Callanan 
174dbb271fSSean Callanan namespace lldb_private {
184dbb271fSSean Callanan 
19f05b42e9SAdrian Prantl /// \class ASTStructExtractor ASTStructExtractor.h
20d8f460e8SAdrian Prantl /// "lldb/Expression/ASTStructExtractor.h" Extracts and describes the argument
21d8f460e8SAdrian Prantl /// structure for a wrapped function.
224dbb271fSSean Callanan ///
23b9c1b51eSKate Stone /// This pass integrates with ClangFunctionCaller, which calls functions with
24d8f460e8SAdrian Prantl /// custom sets of arguments.  To avoid having to implement the full calling
25d8f460e8SAdrian Prantl /// convention for the target's architecture, ClangFunctionCaller writes a
26d8f460e8SAdrian Prantl /// simple wrapper function that takes a pointer to an argument structure that
27d8f460e8SAdrian Prantl /// contains room for the address of the function to be called, the values of
28d8f460e8SAdrian Prantl /// all its arguments, and room for the function's return value.
294dbb271fSSean Callanan ///
30d8f460e8SAdrian Prantl /// The definition of this struct is itself in the body of the wrapper
31d8f460e8SAdrian Prantl /// function, so Clang does the structure layout itself.  ASTStructExtractor
32d8f460e8SAdrian Prantl /// reads through the AST for the wrapper function and finds the struct.
33b9c1b51eSKate Stone class ASTStructExtractor : public clang::SemaConsumer {
344dbb271fSSean Callanan public:
354dbb271fSSean Callanan   /// Constructor
364dbb271fSSean Callanan   ///
37f05b42e9SAdrian Prantl   /// \param[in] passthrough
384dbb271fSSean Callanan   ///     Since the ASTs must typically go through to the Clang code generator
394dbb271fSSean Callanan   ///     in order to produce LLVM IR, this SemaConsumer must allow them to
404dbb271fSSean Callanan   ///     pass to the next step in the chain after processing.  Passthrough is
414dbb271fSSean Callanan   ///     the next ASTConsumer, or NULL if none is required.
424dbb271fSSean Callanan   ///
43f05b42e9SAdrian Prantl   /// \param[in] struct_name
444dbb271fSSean Callanan   ///     The name of the structure to extract from the wrapper function.
454dbb271fSSean Callanan   ///
46f05b42e9SAdrian Prantl   /// \param[in] function
474dbb271fSSean Callanan   ///     The caller object whose members should be populated with information
48b9c1b51eSKate Stone   ///     about the argument struct.  ClangFunctionCaller friends
49b9c1b51eSKate Stone   ///     ASTStructExtractor
504dbb271fSSean Callanan   ///     for this purpose.
51b9c1b51eSKate Stone   ASTStructExtractor(clang::ASTConsumer *passthrough, const char *struct_name,
524dbb271fSSean Callanan                      ClangFunctionCaller &function);
534dbb271fSSean Callanan 
544dbb271fSSean Callanan   /// Destructor
554dbb271fSSean Callanan   ~ASTStructExtractor() override;
564dbb271fSSean Callanan 
574dbb271fSSean Callanan   /// Link this consumer with a particular AST context
584dbb271fSSean Callanan   ///
59f05b42e9SAdrian Prantl   /// \param[in] Context
604dbb271fSSean Callanan   ///     This AST context will be used for types and identifiers, and also
614dbb271fSSean Callanan   ///     forwarded to the passthrough consumer, if one exists.
624dbb271fSSean Callanan   void Initialize(clang::ASTContext &Context) override;
634dbb271fSSean Callanan 
64d8f460e8SAdrian Prantl   /// Examine a list of Decls to find the function $__lldb_expr and transform
65d8f460e8SAdrian Prantl   /// its code
664dbb271fSSean Callanan   ///
67f05b42e9SAdrian Prantl   /// \param[in] D
684dbb271fSSean Callanan   ///     The list of Decls to search.  These may contain LinkageSpecDecls,
694dbb271fSSean Callanan   ///     which need to be searched recursively.  That job falls to
704dbb271fSSean Callanan   ///     TransformTopLevelDecl.
714dbb271fSSean Callanan   bool HandleTopLevelDecl(clang::DeclGroupRef D) override;
724dbb271fSSean Callanan 
734dbb271fSSean Callanan   /// Passthrough stub
744dbb271fSSean Callanan   void HandleTranslationUnit(clang::ASTContext &Ctx) override;
754dbb271fSSean Callanan 
764dbb271fSSean Callanan   /// Passthrough stub
774dbb271fSSean Callanan   void HandleTagDeclDefinition(clang::TagDecl *D) override;
784dbb271fSSean Callanan 
794dbb271fSSean Callanan   /// Passthrough stub
804dbb271fSSean Callanan   void CompleteTentativeDefinition(clang::VarDecl *D) override;
814dbb271fSSean Callanan 
824dbb271fSSean Callanan   /// Passthrough stub
834dbb271fSSean Callanan   void HandleVTable(clang::CXXRecordDecl *RD) override;
844dbb271fSSean Callanan 
854dbb271fSSean Callanan   /// Passthrough stub
864dbb271fSSean Callanan   void PrintStats() override;
874dbb271fSSean Callanan 
884dbb271fSSean Callanan   /// Set the Sema object to use when performing transforms, and pass it on
894dbb271fSSean Callanan   ///
90f05b42e9SAdrian Prantl   /// \param[in] S
914dbb271fSSean Callanan   ///     The Sema to use.  Because Sema isn't externally visible, this class
924dbb271fSSean Callanan   ///     casts it to an Action for actual use.
934dbb271fSSean Callanan   void InitializeSema(clang::Sema &S) override;
944dbb271fSSean Callanan 
954dbb271fSSean Callanan   /// Reset the Sema to NULL now that transformations are done
964dbb271fSSean Callanan   void ForgetSema() override;
974dbb271fSSean Callanan 
984dbb271fSSean Callanan private:
994dbb271fSSean Callanan   /// Hunt the given FunctionDecl for the argument struct and place
1004dbb271fSSean Callanan   /// information about it into m_function
1014dbb271fSSean Callanan   ///
102f05b42e9SAdrian Prantl   /// \param[in] F
1034dbb271fSSean Callanan   ///     The FunctionDecl to hunt.
104b9c1b51eSKate Stone   void ExtractFromFunctionDecl(clang::FunctionDecl *F);
1054dbb271fSSean Callanan 
1064dbb271fSSean Callanan   /// Hunt the given Decl for FunctionDecls named the same as the wrapper
1074dbb271fSSean Callanan   /// function name, recursing as necessary through LinkageSpecDecls, and
1084dbb271fSSean Callanan   /// calling ExtractFromFunctionDecl on anything that was found
1094dbb271fSSean Callanan   ///
110f05b42e9SAdrian Prantl   /// \param[in] D
1114dbb271fSSean Callanan   ///     The Decl to hunt.
112b9c1b51eSKate Stone   void ExtractFromTopLevelDecl(clang::Decl *D);
1134dbb271fSSean Callanan 
114b9c1b51eSKate Stone   clang::ASTContext
115b9c1b51eSKate Stone       *m_ast_context; ///< The AST context to use for identifiers and types.
116b9c1b51eSKate Stone   clang::ASTConsumer *m_passthrough; ///< The ASTConsumer down the chain, for
117b9c1b51eSKate Stone                                      ///passthrough.  NULL if it's a
118b9c1b51eSKate Stone                                      ///SemaConsumer.
119b9c1b51eSKate Stone   clang::SemaConsumer *m_passthrough_sema; ///< The SemaConsumer down the chain,
120b9c1b51eSKate Stone                                            ///for passthrough.  NULL if it's an
121b9c1b51eSKate Stone                                            ///ASTConsumer.
1224dbb271fSSean Callanan   clang::Sema *m_sema;                     ///< The Sema to use.
1234dbb271fSSean Callanan 
124b9c1b51eSKate Stone   ClangFunctionCaller &m_function; ///< The function to populate with
125b9c1b51eSKate Stone                                    ///information about the argument structure.
1264dbb271fSSean Callanan   std::string m_struct_name;       ///< The name of the structure to extract.
1274dbb271fSSean Callanan };
1284dbb271fSSean Callanan 
1294dbb271fSSean Callanan } // namespace lldb_private
1304dbb271fSSean Callanan 
131*cdc514e4SJonas Devlieghere #endif // LLDB_SOURCE_PLUGINS_EXPRESSIONPARSER_CLANG_ASTSTRUCTEXTRACTOR_H
132