//===-- ClangFunction.h -----------------------------------------*- C++ -*-===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// #ifndef lldb_ClangFunction_h_ #define lldb_ClangFunction_h_ // C Includes // C++ Includes #include <vector> #include <list> // Other libraries and framework includes // Project includes #include "lldb/Core/ClangForward.h" #include "lldb/Core/Address.h" #include "lldb/Core/ArchSpec.h" #include "lldb/Core/Value.h" #include "lldb/Core/ValueObjectList.h" #include "lldb/Expression/ClangExpression.h" #include "lldb/Target/Process.h" namespace lldb_private { class ASTStructExtractor; class ClangExpressionParser; //---------------------------------------------------------------------- /// @class ClangFunction ClangFunction.h "lldb/Expression/ClangFunction.h" /// @brief Encapsulates a function that can be called. /// /// A given ClangFunction object can handle a single function signature. /// Once constructed, it can set up any number of concurrent calls to /// functions with that signature. /// /// It performs the call by synthesizing a structure that contains the pointer /// to the function and the arguments that should be passed to that function, /// and producing a special-purpose JIT-compiled function that accepts a void* /// pointing to this struct as its only argument and calls the function in the /// struct with the written arguments. This method lets Clang handle the /// vagaries of function calling conventions. /// /// The simplest use of the ClangFunction is to construct it with a /// function representative of the signature you want to use, then call /// ExecuteFunction(ExecutionContext &, Stream &, Value &). /// /// If you need to reuse the arguments for several calls, you can call /// InsertFunction() followed by WriteFunctionArguments(), which will return /// the location of the args struct for the wrapper function in args_addr_ref. /// /// If you need to call the function on the thread plan stack, you can also /// call InsertFunction() followed by GetThreadPlanToCallFunction(). /// /// Any of the methods that take arg_addr_ptr or arg_addr_ref can be passed /// a pointer set to LLDB_INVALID_ADDRESS and new structure will be allocated /// and its address returned in that variable. /// /// Any of the methods that take arg_addr_ptr can be passed NULL, and the /// argument space will be managed for you. //---------------------------------------------------------------------- class ClangFunction : public ClangExpression { friend class ASTStructExtractor; public: //------------------------------------------------------------------ /// Constructor /// /// @param[in] exe_scope /// An execution context scope that gets us at least a target and /// process. /// /// @param[in] function_ptr /// The default function to be called. Can be overridden using /// WriteFunctionArguments(). /// /// @param[in] ast_context /// The AST context to evaluate argument types in. /// /// @param[in] arg_value_list /// The default values to use when calling this function. Can /// be overridden using WriteFunctionArguments(). //------------------------------------------------------------------ ClangFunction (ExecutionContextScope &exe_scope, Function &function_ptr, ClangASTContext *ast_context, const ValueList &arg_value_list); //------------------------------------------------------------------ /// Constructor /// /// @param[in] exe_scope /// An execution context scope that gets us at least a target and /// process. /// /// @param[in] ast_context /// The AST context to evaluate argument types in. /// /// @param[in] return_qualtype /// An opaque Clang QualType for the function result. Should be /// defined in ast_context. /// /// @param[in] function_address /// The address of the function to call. /// /// @param[in] arg_value_list /// The default values to use when calling this function. Can /// be overridden using WriteFunctionArguments(). //------------------------------------------------------------------ ClangFunction (ExecutionContextScope &exe_scope, const ClangASTType &return_type, const Address& function_address, const ValueList &arg_value_list); //------------------------------------------------------------------ /// Destructor //------------------------------------------------------------------ virtual ~ClangFunction(); //------------------------------------------------------------------ /// Compile the wrapper function /// /// @param[in] errors /// The stream to print parser errors to. /// /// @return /// The number of errors. //------------------------------------------------------------------ unsigned CompileFunction (Stream &errors); //------------------------------------------------------------------ /// Insert the default function wrapper and its default argument struct /// /// @param[in] exe_ctx /// The execution context to insert the function and its arguments /// into. /// /// @param[in,out] args_addr_ref /// The address of the structure to write the arguments into. May /// be LLDB_INVALID_ADDRESS; if it is, a new structure is allocated /// and args_addr_ref is pointed to it. /// /// @param[in] errors /// The stream to write errors to. /// /// @return /// True on success; false otherwise. //------------------------------------------------------------------ bool InsertFunction (ExecutionContext &exe_ctx, lldb::addr_t &args_addr_ref, Stream &errors); //------------------------------------------------------------------ /// Insert the default function wrapper (using the JIT) /// /// @param[in] exe_ctx /// The execution context to insert the function and its arguments /// into. /// /// @param[in] errors /// The stream to write errors to. /// /// @return /// True on success; false otherwise. //------------------------------------------------------------------ bool WriteFunctionWrapper (ExecutionContext &exe_ctx, Stream &errors); //------------------------------------------------------------------ /// Insert the default function argument struct /// /// @param[in] exe_ctx /// The execution context to insert the function and its arguments /// into. /// /// @param[in,out] args_addr_ref /// The address of the structure to write the arguments into. May /// be LLDB_INVALID_ADDRESS; if it is, a new structure is allocated /// and args_addr_ref is pointed to it. /// /// @param[in] errors /// The stream to write errors to. /// /// @return /// True on success; false otherwise. //------------------------------------------------------------------ bool WriteFunctionArguments (ExecutionContext &exe_ctx, lldb::addr_t &args_addr_ref, Stream &errors); //------------------------------------------------------------------ /// Insert an argument struct with a non-default function address and /// non-default argument values /// /// @param[in] exe_ctx /// The execution context to insert the function and its arguments /// into. /// /// @param[in,out] args_addr_ref /// The address of the structure to write the arguments into. May /// be LLDB_INVALID_ADDRESS; if it is, a new structure is allocated /// and args_addr_ref is pointed to it. /// /// @param[in] function_address /// The address of the function to call. /// /// @param[in] arg_values /// The values of the function's arguments. /// /// @param[in] errors /// The stream to write errors to. /// /// @return /// True on success; false otherwise. //------------------------------------------------------------------ bool WriteFunctionArguments (ExecutionContext &exe_ctx, lldb::addr_t &args_addr_ref, Address function_address, ValueList &arg_values, Stream &errors); //------------------------------------------------------------------ /// Run the function this ClangFunction was created with. /// /// This is the full version. /// /// @param[in] exe_ctx /// The thread & process in which this function will run. /// /// @param[in] args_addr_ptr /// If NULL, the function will take care of allocating & deallocating the wrapper /// args structure. Otherwise, if set to LLDB_INVALID_ADDRESS, a new structure /// will be allocated, filled and the address returned to you. You are responsible /// for deallocating it. And if passed in with a value other than LLDB_INVALID_ADDRESS, /// this should point to an already allocated structure with the values already written. /// /// @param[in] errors /// Errors will be written here if there are any. /// /// @param[in] options /// The options for this expression execution. /// /// @param[out] results /// The result value will be put here after running the function. /// /// @return /// Returns one of the ExecutionResults enum indicating function call status. //------------------------------------------------------------------ ExecutionResults ExecuteFunction(ExecutionContext &exe_ctx, lldb::addr_t *args_addr_ptr, const EvaluateExpressionOptions &options, Stream &errors, Value &results); //------------------------------------------------------------------ /// Get a thread plan to run the function this ClangFunction was created with. /// /// @param[in] exe_ctx /// The execution context to insert the function and its arguments /// into. /// /// @param[in] func_addr /// The address of the function in the target process. /// /// @param[in] args_addr /// The address of the argument struct. /// /// @param[in] errors /// The stream to write errors to. /// /// @param[in] stop_others /// True if other threads should pause during execution. /// /// @param[in] unwind_on_error /// True if the thread plan may simply be discarded if an error occurs. /// /// @return /// A ThreadPlan for executing the function. //------------------------------------------------------------------ ThreadPlan * GetThreadPlanToCallFunction (ExecutionContext &exe_ctx, lldb::addr_t args_addr, const EvaluateExpressionOptions &options, Stream &errors); //------------------------------------------------------------------ /// Get the result of the function from its struct /// /// @param[in] exe_ctx /// The execution context to retrieve the result from. /// /// @param[in] args_addr /// The address of the argument struct. /// /// @param[in] ret_value /// The value returned by the function. /// /// @return /// True on success; false otherwise. //------------------------------------------------------------------ bool FetchFunctionResults (ExecutionContext &exe_ctx, lldb::addr_t args_addr, Value &ret_value); //------------------------------------------------------------------ /// Deallocate the arguments structure /// /// @param[in] exe_ctx /// The execution context to insert the function and its arguments /// into. /// /// @param[in] args_addr /// The address of the argument struct. //------------------------------------------------------------------ void DeallocateFunctionResults (ExecutionContext &exe_ctx, lldb::addr_t args_addr); //------------------------------------------------------------------ /// Interface for ClangExpression //------------------------------------------------------------------ //------------------------------------------------------------------ /// Return the string that the parser should parse. Must be a full /// translation unit. //------------------------------------------------------------------ const char * Text () { return m_wrapper_function_text.c_str(); } //------------------------------------------------------------------ /// Return the function name that should be used for executing the /// expression. Text() should contain the definition of this /// function. //------------------------------------------------------------------ const char * FunctionName () { return m_wrapper_function_name.c_str(); } //------------------------------------------------------------------ /// Return the object that the parser should use when resolving external /// values. May be NULL if everything should be self-contained. //------------------------------------------------------------------ ClangExpressionDeclMap * DeclMap () { return NULL; } //------------------------------------------------------------------ /// Return the object that the parser should use when registering /// local variables. May be NULL if the Expression doesn't care. //------------------------------------------------------------------ ClangExpressionVariableList * LocalVariables () { return NULL; } //------------------------------------------------------------------ /// Return the object that the parser should allow to access ASTs. /// May be NULL if the ASTs do not need to be transformed. /// /// @param[in] passthrough /// The ASTConsumer that the returned transformer should send /// the ASTs to after transformation. //------------------------------------------------------------------ clang::ASTConsumer * ASTTransformer (clang::ASTConsumer *passthrough); //------------------------------------------------------------------ /// Return true if validation code should be inserted into the /// expression. //------------------------------------------------------------------ bool NeedsValidation () { return false; } //------------------------------------------------------------------ /// Return true if external variables in the expression should be /// resolved. //------------------------------------------------------------------ bool NeedsVariableResolution () { return false; } ValueList GetArgumentValues () const { return m_arg_values; } private: //------------------------------------------------------------------ // For ClangFunction only //------------------------------------------------------------------ std::unique_ptr<ClangExpressionParser> m_parser; ///< The parser responsible for compiling the function. std::unique_ptr<IRExecutionUnit> m_execution_unit_ap; Function *m_function_ptr; ///< The function we're going to call. May be NULL if we don't have debug info for the function. Address m_function_addr; ///< If we don't have the FunctionSP, we at least need the address & return type. ClangASTType m_function_return_type; ///< The opaque clang qual type for the function return type. std::string m_wrapper_function_name; ///< The name of the wrapper function. std::string m_wrapper_function_text; ///< The contents of the wrapper function. std::string m_wrapper_struct_name; ///< The name of the struct that contains the target function address, arguments, and result. std::list<lldb::addr_t> m_wrapper_args_addrs; ///< The addresses of the arguments to the wrapper function. std::unique_ptr<ASTStructExtractor> m_struct_extractor; ///< The class that generates the argument struct below. bool m_struct_valid; ///< True if the ASTStructExtractor has populated the variables below. //------------------------------------------------------------------ /// These values are populated by the ASTStructExtractor size_t m_struct_size; ///< The size of the argument struct, in bytes. std::vector<uint64_t> m_member_offsets; ///< The offset of each member in the struct, in bytes. uint64_t m_return_size; ///< The size of the result variable, in bytes. uint64_t m_return_offset; ///< The offset of the result variable in the struct, in bytes. //------------------------------------------------------------------ ValueList m_arg_values; ///< The default values of the arguments. bool m_compiled; ///< True if the wrapper function has already been parsed. bool m_JITted; ///< True if the wrapper function has already been JIT-compiled. }; } // Namespace lldb_private #endif // lldb_ClangFunction_h_