//===-- ClangFunction.cpp ---------------------------------------*- C++ -*-===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // C Includes // C++ Includes // Other libraries and framework includes #include "clang/AST/ASTContext.h" #include "clang/AST/RecordLayout.h" #include "clang/CodeGen/CodeGenAction.h" #include "clang/CodeGen/ModuleBuilder.h" #include "clang/Frontend/CompilerInstance.h" #include "llvm/ADT/StringRef.h" #include "llvm/ADT/Triple.h" #include "llvm/ExecutionEngine/ExecutionEngine.h" #include "llvm/Module.h" // Project includes #include "lldb/Expression/ASTStructExtractor.h" #include "lldb/Expression/ClangExpressionParser.h" #include "lldb/Expression/ClangFunction.h" #include "lldb/Symbol/Type.h" #include "lldb/Core/DataExtractor.h" #include "lldb/Core/State.h" #include "lldb/Core/ValueObject.h" #include "lldb/Core/ValueObjectList.h" #include "lldb/Interpreter/CommandReturnObject.h" #include "lldb/Symbol/ClangASTContext.h" #include "lldb/Symbol/Function.h" #include "lldb/Target/ExecutionContext.h" #include "lldb/Target/Process.h" #include "lldb/Target/RegisterContext.h" #include "lldb/Target/StopInfo.h" #include "lldb/Target/Target.h" #include "lldb/Target/Thread.h" #include "lldb/Target/ThreadPlan.h" #include "lldb/Target/ThreadPlanCallFunction.h" #include "lldb/Core/Log.h" using namespace lldb_private; //---------------------------------------------------------------------- // ClangFunction constructor //---------------------------------------------------------------------- ClangFunction::ClangFunction ( ExecutionContextScope &exe_scope, ClangASTContext *ast_context, void *return_qualtype, const Address& functionAddress, const ValueList &arg_value_list ) : m_function_ptr (NULL), m_function_addr (functionAddress), m_function_return_qual_type(return_qualtype), m_clang_ast_context (ast_context), m_wrapper_function_name ("__lldb_caller_function"), m_wrapper_struct_name ("__lldb_caller_struct"), m_wrapper_args_addrs (), m_arg_values (arg_value_list), m_compiled (false), m_JITted (false) { Process *process = exe_scope.CalculateProcess(); // Can't make a ClangFunction without a process. assert (process != NULL); m_jit_process_sp = process->GetSP(); } ClangFunction::ClangFunction ( ExecutionContextScope &exe_scope, Function &function, ClangASTContext *ast_context, const ValueList &arg_value_list ) : m_function_ptr (&function), m_function_addr (), m_function_return_qual_type (), m_clang_ast_context (ast_context), m_wrapper_function_name ("__lldb_function_caller"), m_wrapper_struct_name ("__lldb_caller_struct"), m_wrapper_args_addrs (), m_arg_values (arg_value_list), m_compiled (false), m_JITted (false) { Process *process = exe_scope.CalculateProcess(); // Can't make a ClangFunction without a process. assert (process != NULL); m_jit_process_sp = process->GetSP(); m_function_addr = m_function_ptr->GetAddressRange().GetBaseAddress(); m_function_return_qual_type = m_function_ptr->GetReturnClangType(); } //---------------------------------------------------------------------- // Destructor //---------------------------------------------------------------------- ClangFunction::~ClangFunction() { } unsigned ClangFunction::CompileFunction (Stream &errors) { if (m_compiled) return 0; // FIXME: How does clang tell us there's no return value? We need to handle that case. unsigned num_errors = 0; std::string return_type_str (ClangASTType::GetTypeNameForOpaqueQualType (m_function_return_qual_type)); // Cons up the function we're going to wrap our call in, then compile it... // We declare the function "extern "C"" because the compiler might be in C++ // mode which would mangle the name and then we couldn't find it again... m_wrapper_function_text.clear(); m_wrapper_function_text.append ("extern \"C\" void "); m_wrapper_function_text.append (m_wrapper_function_name); m_wrapper_function_text.append (" (void *input)\n{\n struct "); m_wrapper_function_text.append (m_wrapper_struct_name); m_wrapper_function_text.append (" \n {\n"); m_wrapper_function_text.append (" "); m_wrapper_function_text.append (return_type_str); m_wrapper_function_text.append (" (*fn_ptr) ("); // Get the number of arguments. If we have a function type and it is prototyped, // trust that, otherwise use the values we were given. // FIXME: This will need to be extended to handle Variadic functions. We'll need // to pull the defined arguments out of the function, then add the types from the // arguments list for the variable arguments. uint32_t num_args = UINT32_MAX; bool trust_function = false; // GetArgumentCount returns -1 for an unprototyped function. if (m_function_ptr) { int num_func_args = m_function_ptr->GetArgumentCount(); if (num_func_args >= 0) trust_function = true; else num_args = num_func_args; } if (num_args == UINT32_MAX) num_args = m_arg_values.GetSize(); std::string args_buffer; // This one stores the definition of all the args in "struct caller". std::string args_list_buffer; // This one stores the argument list called from the structure. for (size_t i = 0; i < num_args; i++) { std::string type_name; if (trust_function) { lldb::clang_type_t arg_clang_type = m_function_ptr->GetArgumentTypeAtIndex(i); type_name = ClangASTType::GetTypeNameForOpaqueQualType (arg_clang_type); } else { Value *arg_value = m_arg_values.GetValueAtIndex(i); lldb::clang_type_t clang_qual_type = arg_value->GetClangType (); if (clang_qual_type != NULL) { type_name = ClangASTType::GetTypeNameForOpaqueQualType (clang_qual_type); } else { errors.Printf("Could not determine type of input value %d.", i); return 1; } } m_wrapper_function_text.append (type_name); if (i < num_args - 1) m_wrapper_function_text.append (", "); char arg_buf[32]; args_buffer.append (" "); args_buffer.append (type_name); snprintf(arg_buf, 31, "arg_%zd", i); args_buffer.push_back (' '); args_buffer.append (arg_buf); args_buffer.append (";\n"); args_list_buffer.append ("__lldb_fn_data->"); args_list_buffer.append (arg_buf); if (i < num_args - 1) args_list_buffer.append (", "); } m_wrapper_function_text.append (");\n"); // Close off the function calling prototype. m_wrapper_function_text.append (args_buffer); m_wrapper_function_text.append (" "); m_wrapper_function_text.append (return_type_str); m_wrapper_function_text.append (" return_value;"); m_wrapper_function_text.append ("\n };\n struct "); m_wrapper_function_text.append (m_wrapper_struct_name); m_wrapper_function_text.append ("* __lldb_fn_data = (struct "); m_wrapper_function_text.append (m_wrapper_struct_name); m_wrapper_function_text.append (" *) input;\n"); m_wrapper_function_text.append (" __lldb_fn_data->return_value = __lldb_fn_data->fn_ptr ("); m_wrapper_function_text.append (args_list_buffer); m_wrapper_function_text.append (");\n}\n"); lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS)); if (log) log->Printf ("Expression: \n\n%s\n\n", m_wrapper_function_text.c_str()); // Okay, now compile this expression m_parser.reset(new ClangExpressionParser(m_jit_process_sp.get(), *this)); num_errors = m_parser->Parse (errors); m_compiled = (num_errors == 0); if (!m_compiled) return num_errors; return num_errors; } bool ClangFunction::WriteFunctionWrapper (ExecutionContext &exe_ctx, Stream &errors) { Process *process = exe_ctx.process; if (!process) return false; if (process != m_jit_process_sp.get()) return false; if (!m_compiled) return false; if (m_JITted) return true; lldb::ClangExpressionVariableSP const_result; bool evaluated_statically = false; // should stay that way Error jit_error (m_parser->PrepareForExecution (m_jit_alloc, m_jit_start_addr, m_jit_end_addr, exe_ctx, NULL, evaluated_statically, const_result, eExecutionPolicyAlways)); if (!jit_error.Success()) return false; if (exe_ctx.process && m_jit_alloc != LLDB_INVALID_ADDRESS) m_jit_process_sp = exe_ctx.process->GetSP(); return true; } bool ClangFunction::WriteFunctionArguments (ExecutionContext &exe_ctx, lldb::addr_t &args_addr_ref, Stream &errors) { return WriteFunctionArguments(exe_ctx, args_addr_ref, m_function_addr, m_arg_values, errors); } // FIXME: Assure that the ValueList we were passed in is consistent with the one that defined this function. bool ClangFunction::WriteFunctionArguments (ExecutionContext &exe_ctx, lldb::addr_t &args_addr_ref, Address function_address, ValueList &arg_values, Stream &errors) { // All the information to reconstruct the struct is provided by the // StructExtractor. if (!m_struct_valid) { errors.Printf("Argument information was not correctly parsed, so the function cannot be called."); return false; } Error error; using namespace clang; ExecutionResults return_value = eExecutionSetupError; Process *process = exe_ctx.process; if (process == NULL) return return_value; if (process != m_jit_process_sp.get()) return false; if (args_addr_ref == LLDB_INVALID_ADDRESS) { args_addr_ref = process->AllocateMemory(m_struct_size, lldb::ePermissionsReadable|lldb::ePermissionsWritable, error); if (args_addr_ref == LLDB_INVALID_ADDRESS) return false; m_wrapper_args_addrs.push_back (args_addr_ref); } else { // Make sure this is an address that we've already handed out. if (find (m_wrapper_args_addrs.begin(), m_wrapper_args_addrs.end(), args_addr_ref) == m_wrapper_args_addrs.end()) { return false; } } // TODO: verify fun_addr needs to be a callable address Scalar fun_addr (function_address.GetCallableLoadAddress(exe_ctx.target)); int first_offset = m_member_offsets[0]; process->WriteScalarToMemory(args_addr_ref + first_offset, fun_addr, process->GetAddressByteSize(), error); // FIXME: We will need to extend this for Variadic functions. Error value_error; size_t num_args = arg_values.GetSize(); if (num_args != m_arg_values.GetSize()) { errors.Printf ("Wrong number of arguments - was: %d should be: %d", num_args, m_arg_values.GetSize()); return false; } for (size_t i = 0; i < num_args; i++) { // FIXME: We should sanity check sizes. int offset = m_member_offsets[i+1]; // Clang sizes are in bytes. Value *arg_value = arg_values.GetValueAtIndex(i); // FIXME: For now just do scalars: // Special case: if it's a pointer, don't do anything (the ABI supports passing cstrings) if (arg_value->GetValueType() == Value::eValueTypeHostAddress && arg_value->GetContextType() == Value::eContextTypeClangType && ClangASTContext::IsPointerType(arg_value->GetClangType())) continue; const Scalar &arg_scalar = arg_value->ResolveValue(&exe_ctx, m_clang_ast_context->getASTContext()); if (!process->WriteScalarToMemory(args_addr_ref + offset, arg_scalar, arg_scalar.GetByteSize(), error)) return false; } return true; } bool ClangFunction::InsertFunction (ExecutionContext &exe_ctx, lldb::addr_t &args_addr_ref, Stream &errors) { using namespace clang; if (CompileFunction(errors) != 0) return false; if (!WriteFunctionWrapper(exe_ctx, errors)) return false; if (!WriteFunctionArguments(exe_ctx, args_addr_ref, errors)) return false; lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP)); if (log) log->Printf ("Call Address: 0x%llx Struct Address: 0x%llx.\n", m_jit_start_addr, args_addr_ref); return true; } ThreadPlan * ClangFunction::GetThreadPlanToCallFunction (ExecutionContext &exe_ctx, lldb::addr_t func_addr, lldb::addr_t &args_addr, Stream &errors, bool stop_others, bool discard_on_error, lldb::addr_t *this_arg, lldb::addr_t *cmd_arg) { // FIXME: Use the errors Stream for better error reporting. if (exe_ctx.thread == NULL) { errors.Printf("Can't call a function without a valid thread."); return NULL; } // Okay, now run the function: Address wrapper_address (NULL, func_addr); ThreadPlan *new_plan = new ThreadPlanCallFunction (*exe_ctx.thread, wrapper_address, args_addr, stop_others, discard_on_error, this_arg, cmd_arg); return new_plan; } bool ClangFunction::FetchFunctionResults (ExecutionContext &exe_ctx, lldb::addr_t args_addr, Value &ret_value) { // Read the return value - it is the last field in the struct: // FIXME: How does clang tell us there's no return value? We need to handle that case. Process *process = exe_ctx.process; if (process == NULL) return false; if (process != m_jit_process_sp.get()) return false; Error error; ret_value.GetScalar() = process->ReadUnsignedIntegerFromMemory (args_addr + m_return_offset, m_return_size, 0, error); if (error.Fail()) return false; ret_value.SetContext (Value::eContextTypeClangType, m_function_return_qual_type); ret_value.SetValueType(Value::eValueTypeScalar); return true; } void ClangFunction::DeallocateFunctionResults (ExecutionContext &exe_ctx, lldb::addr_t args_addr) { std::list::iterator pos; pos = std::find(m_wrapper_args_addrs.begin(), m_wrapper_args_addrs.end(), args_addr); if (pos != m_wrapper_args_addrs.end()) m_wrapper_args_addrs.erase(pos); exe_ctx.process->DeallocateMemory(args_addr); } ExecutionResults ClangFunction::ExecuteFunction(ExecutionContext &exe_ctx, Stream &errors, Value &results) { return ExecuteFunction (exe_ctx, errors, 1000, true, results); } ExecutionResults ClangFunction::ExecuteFunction(ExecutionContext &exe_ctx, Stream &errors, bool stop_others, Value &results) { const bool try_all_threads = false; const bool discard_on_error = true; return ExecuteFunction (exe_ctx, NULL, errors, stop_others, NULL, try_all_threads, discard_on_error, results); } ExecutionResults ClangFunction::ExecuteFunction( ExecutionContext &exe_ctx, Stream &errors, uint32_t single_thread_timeout_usec, bool try_all_threads, Value &results) { const bool stop_others = true; const bool discard_on_error = true; return ExecuteFunction (exe_ctx, NULL, errors, stop_others, single_thread_timeout_usec, try_all_threads, discard_on_error, results); } // This is the static function ExecutionResults ClangFunction::ExecuteFunction ( ExecutionContext &exe_ctx, lldb::addr_t function_address, lldb::addr_t &void_arg, bool stop_others, bool try_all_threads, bool discard_on_error, uint32_t single_thread_timeout_usec, Stream &errors, lldb::addr_t *this_arg) { lldb::ThreadPlanSP call_plan_sp(ClangFunction::GetThreadPlanToCallFunction(exe_ctx, function_address, void_arg, errors, stop_others, discard_on_error, this_arg)); if (call_plan_sp == NULL) return eExecutionSetupError; call_plan_sp->SetPrivate(true); return exe_ctx.process->RunThreadPlan (exe_ctx, call_plan_sp, stop_others, try_all_threads, discard_on_error, single_thread_timeout_usec, errors); } ExecutionResults ClangFunction::ExecuteFunction( ExecutionContext &exe_ctx, lldb::addr_t *args_addr_ptr, Stream &errors, bool stop_others, uint32_t single_thread_timeout_usec, bool try_all_threads, bool discard_on_error, Value &results) { using namespace clang; ExecutionResults return_value = eExecutionSetupError; lldb::addr_t args_addr; if (args_addr_ptr != NULL) args_addr = *args_addr_ptr; else args_addr = LLDB_INVALID_ADDRESS; if (CompileFunction(errors) != 0) return eExecutionSetupError; if (args_addr == LLDB_INVALID_ADDRESS) { if (!InsertFunction(exe_ctx, args_addr, errors)) return eExecutionSetupError; } return_value = ClangFunction::ExecuteFunction (exe_ctx, m_jit_start_addr, args_addr, stop_others, try_all_threads, discard_on_error, single_thread_timeout_usec, errors); if (args_addr_ptr != NULL) *args_addr_ptr = args_addr; if (return_value != eExecutionCompleted) return return_value; FetchFunctionResults(exe_ctx, args_addr, results); if (args_addr_ptr == NULL) DeallocateFunctionResults(exe_ctx, args_addr); return eExecutionCompleted; } clang::ASTConsumer * ClangFunction::ASTTransformer (clang::ASTConsumer *passthrough) { return new ASTStructExtractor(passthrough, m_wrapper_struct_name.c_str(), *this); }