diff options
Diffstat (limited to 'contrib/llvm-project/lldb/source/Plugins/ExpressionParser/Clang/ASTResultSynthesizer.h')
| -rw-r--r-- | contrib/llvm-project/lldb/source/Plugins/ExpressionParser/Clang/ASTResultSynthesizer.h | 173 |
1 files changed, 173 insertions, 0 deletions
diff --git a/contrib/llvm-project/lldb/source/Plugins/ExpressionParser/Clang/ASTResultSynthesizer.h b/contrib/llvm-project/lldb/source/Plugins/ExpressionParser/Clang/ASTResultSynthesizer.h new file mode 100644 index 000000000000..9de823bc75a7 --- /dev/null +++ b/contrib/llvm-project/lldb/source/Plugins/ExpressionParser/Clang/ASTResultSynthesizer.h @@ -0,0 +1,173 @@ +//===-- ASTResultSynthesizer.h ----------------------------------*- C++ -*-===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#ifndef LLDB_SOURCE_PLUGINS_EXPRESSIONPARSER_CLANG_ASTRESULTSYNTHESIZER_H +#define LLDB_SOURCE_PLUGINS_EXPRESSIONPARSER_CLANG_ASTRESULTSYNTHESIZER_H + +#include "lldb/Target/Target.h" +#include "clang/Sema/SemaConsumer.h" + +namespace clang { +class CompoundStmt; +class DeclContext; +class NamedDecl; +class ObjCMethodDecl; +class TypeDecl; +} // namespace clang + +namespace lldb_private { + +/// \class ASTResultSynthesizer ASTResultSynthesizer.h +/// "lldb/Expression/ASTResultSynthesizer.h" Adds a result variable +/// declaration to the ASTs for an expression. +/// +/// Users expect the expression "i + 3" to return a result, even if a result +/// variable wasn't specifically declared. To fulfil this requirement, LLDB +/// adds a result variable to the expression, transforming it to "int +/// $__lldb_expr_result = i + 3." The IR transformers ensure that the +/// resulting variable is mapped to the right piece of memory. +/// ASTResultSynthesizer's job is to add the variable and its initialization +/// to the ASTs for the expression, and it does so by acting as a SemaConsumer +/// for Clang. +class ASTResultSynthesizer : public clang::SemaConsumer { +public: + /// Constructor + /// + /// \param[in] passthrough + /// Since the ASTs must typically go through to the Clang code generator + /// in order to produce LLVM IR, this SemaConsumer must allow them to + /// pass to the next step in the chain after processing. Passthrough is + /// the next ASTConsumer, or NULL if none is required. + /// + /// \param[in] top_level + /// If true, register all top-level Decls and don't try to handle the + /// main function. + /// + /// \param[in] target + /// The target, which contains the persistent variable store and the + /// AST importer. + ASTResultSynthesizer(clang::ASTConsumer *passthrough, bool top_level, + Target &target); + + /// Destructor + ~ASTResultSynthesizer() override; + + /// Link this consumer with a particular AST context + /// + /// \param[in] Context + /// This AST context will be used for types and identifiers, and also + /// forwarded to the passthrough consumer, if one exists. + void Initialize(clang::ASTContext &Context) override; + + /// Examine a list of Decls to find the function $__lldb_expr and transform + /// its code + /// + /// \param[in] D + /// The list of Decls to search. These may contain LinkageSpecDecls, + /// which need to be searched recursively. That job falls to + /// TransformTopLevelDecl. + bool HandleTopLevelDecl(clang::DeclGroupRef D) override; + + /// Passthrough stub + void HandleTranslationUnit(clang::ASTContext &Ctx) override; + + /// Passthrough stub + void HandleTagDeclDefinition(clang::TagDecl *D) override; + + /// Passthrough stub + void CompleteTentativeDefinition(clang::VarDecl *D) override; + + /// Passthrough stub + void HandleVTable(clang::CXXRecordDecl *RD) override; + + /// Passthrough stub + void PrintStats() override; + + /// Set the Sema object to use when performing transforms, and pass it on + /// + /// \param[in] S + /// The Sema to use. Because Sema isn't externally visible, this class + /// casts it to an Action for actual use. + void InitializeSema(clang::Sema &S) override; + + /// Reset the Sema to NULL now that transformations are done + void ForgetSema() override; + + /// The parse has succeeded, so record its persistent decls + void CommitPersistentDecls(); + +private: + /// Hunt the given Decl for FunctionDecls named $__lldb_expr, recursing as + /// necessary through LinkageSpecDecls, and calling SynthesizeResult on + /// anything that was found + /// + /// \param[in] D + /// The Decl to hunt. + void TransformTopLevelDecl(clang::Decl *D); + + /// Process an Objective-C method and produce the result variable and + /// initialization + /// + /// \param[in] MethodDecl + /// The method to process. + bool SynthesizeObjCMethodResult(clang::ObjCMethodDecl *MethodDecl); + + /// Process a function and produce the result variable and initialization + /// + /// \param[in] FunDecl + /// The function to process. + bool SynthesizeFunctionResult(clang::FunctionDecl *FunDecl); + + /// Process a function body and produce the result variable and + /// initialization + /// + /// \param[in] Body + /// The body of the function. + /// + /// \param[in] DC + /// The DeclContext of the function, into which the result variable + /// is inserted. + bool SynthesizeBodyResult(clang::CompoundStmt *Body, clang::DeclContext *DC); + + /// Given a DeclContext for a function or method, find all types declared in + /// the context and record any persistent types found. + /// + /// \param[in] FunDeclCtx + /// The context for the function to process. + void RecordPersistentTypes(clang::DeclContext *FunDeclCtx); + + /// Given a TypeDecl, if it declares a type whose name starts with a dollar + /// sign, register it as a pointer type in the target's scratch AST context. + void MaybeRecordPersistentType(clang::TypeDecl *D); + + /// Given a NamedDecl, register it as a pointer type in the target's scratch + /// AST context. + void RecordPersistentDecl(clang::NamedDecl *D); + + clang::ASTContext + *m_ast_context; ///< The AST context to use for identifiers and types. + clang::ASTConsumer *m_passthrough; ///< The ASTConsumer down the chain, for + ///passthrough. NULL if it's a + ///SemaConsumer. + clang::SemaConsumer *m_passthrough_sema; ///< The SemaConsumer down the chain, + ///for passthrough. NULL if it's an + ///ASTConsumer. + + std::vector<clang::NamedDecl *> m_decls; ///< Persistent declarations to + ///register assuming the expression + ///succeeds. + + Target &m_target; ///< The target, which contains the persistent variable + ///store and the + clang::Sema *m_sema; ///< The Sema to use. + bool m_top_level; +}; + +} // namespace lldb_private + +#endif // LLDB_SOURCE_PLUGINS_EXPRESSIONPARSER_CLANG_ASTRESULTSYNTHESIZER_H |