ClangFunction.h revision 36da2aa6dc5ad9994b638ed09eb81c44cc05540b
1//===-- ClangFunction.h -----------------------------------------*- C++ -*-===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9 10#ifndef lldb_ClangFunction_h_ 11#define lldb_ClangFunction_h_ 12 13// C Includes 14// C++ Includes 15#include <vector> 16#include <list> 17// Other libraries and framework includes 18// Project includes 19#include "lldb/Core/ClangForward.h" 20#include "lldb/Core/Address.h" 21#include "lldb/Core/ArchSpec.h" 22#include "lldb/Core/Value.h" 23#include "lldb/Core/ValueObjectList.h" 24#include "lldb/Expression/ClangExpression.h" 25#include "lldb/Target/Process.h" 26 27namespace lldb_private 28{ 29 30class ASTStructExtractor; 31class ClangExpressionParser; 32 33//---------------------------------------------------------------------- 34/// @class ClangFunction ClangFunction.h "lldb/Expression/ClangFunction.h" 35/// @brief Encapsulates a function that can be called. 36/// 37/// A given ClangFunction object can handle a single function signature. 38/// Once constructed, it can set up any number of concurrent calls to 39/// functions with that signature. 40/// 41/// It performs the call by synthesizing a structure that contains the pointer 42/// to the function and the arguments that should be passed to that function, 43/// and producing a special-purpose JIT-compiled function that accepts a void* 44/// pointing to this struct as its only argument and calls the function in the 45/// struct with the written arguments. This method lets Clang handle the 46/// vagaries of function calling conventions. 47/// 48/// The simplest use of the ClangFunction is to construct it with a 49/// function representative of the signature you want to use, then call 50/// ExecuteFunction(ExecutionContext &, Stream &, Value &). 51/// 52/// If you need to reuse the arguments for several calls, you can call 53/// InsertFunction() followed by WriteFunctionArguments(), which will return 54/// the location of the args struct for the wrapper function in args_addr_ref. 55/// 56/// If you need to call the function on the thread plan stack, you can also 57/// call InsertFunction() followed by GetThreadPlanToCallFunction(). 58/// 59/// Any of the methods that take arg_addr_ptr or arg_addr_ref can be passed 60/// a pointer set to LLDB_INVALID_ADDRESS and new structure will be allocated 61/// and its address returned in that variable. 62/// 63/// Any of the methods that take arg_addr_ptr can be passed NULL, and the 64/// argument space will be managed for you. 65//---------------------------------------------------------------------- 66class ClangFunction : public ClangExpression 67{ 68 friend class ASTStructExtractor; 69public: 70 //------------------------------------------------------------------ 71 /// Constructor 72 /// 73 /// @param[in] exe_scope 74 /// An execution context scope that gets us at least a target and 75 /// process. 76 /// 77 /// @param[in] function_ptr 78 /// The default function to be called. Can be overridden using 79 /// WriteFunctionArguments(). 80 /// 81 /// @param[in] ast_context 82 /// The AST context to evaluate argument types in. 83 /// 84 /// @param[in] arg_value_list 85 /// The default values to use when calling this function. Can 86 /// be overridden using WriteFunctionArguments(). 87 //------------------------------------------------------------------ 88 ClangFunction (ExecutionContextScope &exe_scope, 89 Function &function_ptr, 90 ClangASTContext *ast_context, 91 const ValueList &arg_value_list); 92 93 //------------------------------------------------------------------ 94 /// Constructor 95 /// 96 /// @param[in] exe_scope 97 /// An execution context scope that gets us at least a target and 98 /// process. 99 /// 100 /// @param[in] ast_context 101 /// The AST context to evaluate argument types in. 102 /// 103 /// @param[in] return_qualtype 104 /// An opaque Clang QualType for the function result. Should be 105 /// defined in ast_context. 106 /// 107 /// @param[in] function_address 108 /// The address of the function to call. 109 /// 110 /// @param[in] arg_value_list 111 /// The default values to use when calling this function. Can 112 /// be overridden using WriteFunctionArguments(). 113 //------------------------------------------------------------------ 114 ClangFunction (ExecutionContextScope &exe_scope, 115 ClangASTContext *ast_context, 116 void *return_qualtype, 117 const Address& function_address, 118 const ValueList &arg_value_list); 119 120 //------------------------------------------------------------------ 121 /// Destructor 122 //------------------------------------------------------------------ 123 virtual 124 ~ClangFunction(); 125 126 //------------------------------------------------------------------ 127 /// Compile the wrapper function 128 /// 129 /// @param[in] errors 130 /// The stream to print parser errors to. 131 /// 132 /// @return 133 /// The number of errors. 134 //------------------------------------------------------------------ 135 unsigned 136 CompileFunction (Stream &errors); 137 138 //------------------------------------------------------------------ 139 /// Insert the default function wrapper and its default argument struct 140 /// 141 /// @param[in] exe_ctx 142 /// The execution context to insert the function and its arguments 143 /// into. 144 /// 145 /// @param[in,out] args_addr_ref 146 /// The address of the structure to write the arguments into. May 147 /// be LLDB_INVALID_ADDRESS; if it is, a new structure is allocated 148 /// and args_addr_ref is pointed to it. 149 /// 150 /// @param[in] errors 151 /// The stream to write errors to. 152 /// 153 /// @return 154 /// True on success; false otherwise. 155 //------------------------------------------------------------------ 156 bool 157 InsertFunction (ExecutionContext &exe_ctx, 158 lldb::addr_t &args_addr_ref, 159 Stream &errors); 160 161 //------------------------------------------------------------------ 162 /// Insert the default function wrapper (using the JIT) 163 /// 164 /// @param[in] exe_ctx 165 /// The execution context to insert the function and its arguments 166 /// into. 167 /// 168 /// @param[in] errors 169 /// The stream to write errors to. 170 /// 171 /// @return 172 /// True on success; false otherwise. 173 //------------------------------------------------------------------ 174 bool WriteFunctionWrapper (ExecutionContext &exe_ctx, 175 Stream &errors); 176 177 //------------------------------------------------------------------ 178 /// Insert the default function argument struct 179 /// 180 /// @param[in] exe_ctx 181 /// The execution context to insert the function and its arguments 182 /// into. 183 /// 184 /// @param[in,out] args_addr_ref 185 /// The address of the structure to write the arguments into. May 186 /// be LLDB_INVALID_ADDRESS; if it is, a new structure is allocated 187 /// and args_addr_ref is pointed to it. 188 /// 189 /// @param[in] errors 190 /// The stream to write errors to. 191 /// 192 /// @return 193 /// True on success; false otherwise. 194 //------------------------------------------------------------------ 195 bool WriteFunctionArguments (ExecutionContext &exe_ctx, 196 lldb::addr_t &args_addr_ref, 197 Stream &errors); 198 199 //------------------------------------------------------------------ 200 /// Insert an argument struct with a non-default function address and 201 /// non-default argument values 202 /// 203 /// @param[in] exe_ctx 204 /// The execution context to insert the function and its arguments 205 /// into. 206 /// 207 /// @param[in,out] args_addr_ref 208 /// The address of the structure to write the arguments into. May 209 /// be LLDB_INVALID_ADDRESS; if it is, a new structure is allocated 210 /// and args_addr_ref is pointed to it. 211 /// 212 /// @param[in] function_address 213 /// The address of the function to call. 214 /// 215 /// @param[in] arg_values 216 /// The values of the function's arguments. 217 /// 218 /// @param[in] errors 219 /// The stream to write errors to. 220 /// 221 /// @return 222 /// True on success; false otherwise. 223 //------------------------------------------------------------------ 224 bool WriteFunctionArguments (ExecutionContext &exe_ctx, 225 lldb::addr_t &args_addr_ref, 226 Address function_address, 227 ValueList &arg_values, 228 Stream &errors); 229 230 //------------------------------------------------------------------ 231 /// [Static] Execute a function, passing it a single void* parameter. 232 /// ClangFunction uses this to call the wrapper function. 233 /// 234 /// @param[in] exe_ctx 235 /// The execution context to insert the function and its arguments 236 /// into. 237 /// 238 /// @param[in] function_address 239 /// The address of the function in the target process. 240 /// 241 /// @param[in] void_arg 242 /// The value of the void* parameter. 243 /// 244 /// @param[in] stop_others 245 /// True if other threads should pause during execution. 246 /// 247 /// @param[in] try_all_threads 248 /// If the timeout expires, true if other threads should run. If 249 /// the function may try to take locks, this is useful. 250 /// 251 /// @param[in] unwind_on_error 252 /// If true, and the execution stops before completion, we unwind the 253 /// function call, and return the program state to what it was before the 254 /// execution. If false, we leave the program in the stopped state. 255 /// 256 /// @param[in] timeout_usec 257 /// Timeout value (0 for no timeout). If try_all_threads is true, then we 258 /// will try on one thread for the lesser of .25 sec and half the total timeout. 259 /// then switch to running all threads, otherwise this will be the total timeout. 260 /// 261 /// @param[in] errors 262 /// The stream to write errors to. 263 /// 264 /// @param[in] this_arg 265 /// If non-NULL, the function is invoked like a C++ method, with the 266 /// value pointed to by the pointer as its 'this' argument. 267 /// 268 /// @return 269 /// Returns one of the ExecutionResults enum indicating function call status. 270 //------------------------------------------------------------------ 271 static ExecutionResults 272 ExecuteFunction (ExecutionContext &exe_ctx, 273 lldb::addr_t function_address, 274 lldb::addr_t &void_arg, 275 bool stop_others, 276 bool try_all_threads, 277 bool unwind_on_error, 278 bool ignore_breakpoints, 279 uint32_t timeout_usec, 280 Stream &errors, 281 lldb::addr_t* this_arg = 0); 282 283 //------------------------------------------------------------------ 284 /// Run the function this ClangFunction was created with. 285 /// 286 /// This simple version will run the function stopping other threads 287 /// for a fixed timeout period (1000 usec) and if it does not complete, 288 /// we halt the process and try with all threads running. 289 /// 290 /// @param[in] exe_ctx 291 /// The thread & process in which this function will run. 292 /// 293 /// @param[in] errors 294 /// Errors will be written here if there are any. 295 /// 296 /// @param[out] results 297 /// The result value will be put here after running the function. 298 /// 299 /// @return 300 /// Returns one of the ExecutionResults enum indicating function call status. 301 //------------------------------------------------------------------ 302 ExecutionResults 303 ExecuteFunction(ExecutionContext &exe_ctx, 304 Stream &errors, 305 Value &results); 306 307 //------------------------------------------------------------------ 308 /// Run the function this ClangFunction was created with. 309 /// 310 /// This simple version will run the function obeying the stop_others 311 /// argument. There is no timeout. 312 /// 313 /// @param[in] exe_ctx 314 /// The thread & process in which this function will run. 315 /// 316 /// @param[in] errors 317 /// Errors will be written here if there are any. 318 /// 319 /// @param[in] stop_others 320 /// If \b true, run only this thread, if \b false let all threads run. 321 /// 322 /// @param[out] results 323 /// The result value will be put here after running the function. 324 /// 325 /// @return 326 /// Returns one of the ExecutionResults enum indicating function call status. 327 //------------------------------------------------------------------ 328 ExecutionResults 329 ExecuteFunction(ExecutionContext &exe_ctx, 330 Stream &errors, bool stop_others, 331 Value &results); 332 333 //------------------------------------------------------------------ 334 /// Run the function this ClangFunction was created with. 335 /// 336 /// This simple version will run the function on one thread. If \a timeout_usec 337 /// is not zero, we time out after that timeout. If \a try_all_threads is true, then we will 338 /// resume with all threads on, otherwise we halt the process, and eExecutionInterrupted will be returned. 339 /// 340 /// @param[in] exe_ctx 341 /// The thread & process in which this function will run. 342 /// 343 /// @param[in] errors 344 /// Errors will be written here if there are any. 345 /// 346 /// @param[in] timeout_usec 347 /// Timeout value (0 for no timeout). If try_all_threads is true, then we 348 /// will try on one thread for the lesser of .25 sec and half the total timeout. 349 /// then switch to running all threads, otherwise this will be the total timeout. 350 /// 351 /// @param[in] try_all_threads 352 /// If \b true, run only this thread, if \b false let all threads run. 353 /// 354 /// @param[out] results 355 /// The result value will be put here after running the function. 356 /// 357 /// @return 358 /// Returns one of the ExecutionResults enum indicating function call status. 359 //------------------------------------------------------------------ 360 ExecutionResults 361 ExecuteFunction(ExecutionContext &exe_ctx, 362 Stream &errors, 363 uint32_t single_thread_timeout_usec, 364 bool try_all_threads, 365 Value &results); 366 367 //------------------------------------------------------------------ 368 /// Run the function this ClangFunction was created with. 369 /// 370 /// This is the full version. 371 /// 372 /// @param[in] exe_ctx 373 /// The thread & process in which this function will run. 374 /// 375 /// @param[in] args_addr_ptr 376 /// If NULL, the function will take care of allocating & deallocating the wrapper 377 /// args structure. Otherwise, if set to LLDB_INVALID_ADDRESS, a new structure 378 /// will be allocated, filled and the address returned to you. You are responsible 379 /// for deallocating it. And if passed in with a value other than LLDB_INVALID_ADDRESS, 380 /// this should point to an already allocated structure with the values already written. 381 /// 382 /// @param[in] errors 383 /// Errors will be written here if there are any. 384 /// 385 /// @param[in] stop_others 386 /// If \b true, run only this thread, if \b false let all threads run. 387 /// 388 /// @param[in] timeout_usec 389 /// Timeout value (0 for no timeout). If try_all_threads is true, then we 390 /// will try on one thread for the lesser of .25 sec and half the total timeout. 391 /// then switch to running all threads, otherwise this will be the total timeout. 392 /// 393 /// 394 /// @param[in] try_all_threads 395 /// If \b true, run only this thread, if \b false let all threads run. 396 /// 397 /// @param[out] results 398 /// The result value will be put here after running the function. 399 /// 400 /// @return 401 /// Returns one of the ExecutionResults enum indicating function call status. 402 //------------------------------------------------------------------ 403 ExecutionResults 404 ExecuteFunction(ExecutionContext &exe_ctx, 405 lldb::addr_t *args_addr_ptr, 406 Stream &errors, 407 bool stop_others, 408 uint32_t timeout_usec, 409 bool try_all_threads, 410 bool unwind_on_error, 411 bool ignore_breakpoints, 412 Value &results); 413 414 //------------------------------------------------------------------ 415 /// [static] Get a thread plan to run a function. 416 /// 417 /// @param[in] exe_ctx 418 /// The execution context to insert the function and its arguments 419 /// into. 420 /// 421 /// @param[in] func_addr 422 /// The address of the function in the target process. 423 /// 424 /// @param[in] args_addr_ref 425 /// The value of the void* parameter. 426 /// 427 /// @param[in] errors 428 /// The stream to write errors to. 429 /// 430 /// @param[in] stop_others 431 /// True if other threads should pause during execution. 432 /// 433 /// @param[in] unwind_on_error 434 /// True if the thread plan may simply be discarded if an error occurs. 435 /// 436 /// @param[in] ignore_breakpoints 437 /// True if the expression execution will ignore breakpoint hits and continue executing. 438 /// 439 /// @param[in] this_arg 440 /// If non-NULL (and cmd_arg is NULL), the function is invoked like a C++ 441 /// method, with the value pointed to by the pointer as its 'this' 442 /// argument. 443 /// 444 /// @param[in] cmd_arg 445 /// If non-NULL, the function is invoked like an Objective-C method, with 446 /// this_arg in the 'self' slot and cmd_arg in the '_cmd' slot 447 /// 448 /// @return 449 /// A ThreadPlan for executing the function. 450 //------------------------------------------------------------------ 451 static ThreadPlan * 452 GetThreadPlanToCallFunction (ExecutionContext &exe_ctx, 453 lldb::addr_t func_addr, 454 lldb::addr_t &args_addr_ref, 455 Stream &errors, 456 bool stop_others, 457 bool unwind_on_error, 458 bool ignore_breakpoints, 459 lldb::addr_t *this_arg = 0, 460 lldb::addr_t *cmd_arg = 0); 461 462 //------------------------------------------------------------------ 463 /// Get a thread plan to run the function this ClangFunction was created with. 464 /// 465 /// @param[in] exe_ctx 466 /// The execution context to insert the function and its arguments 467 /// into. 468 /// 469 /// @param[in] func_addr 470 /// The address of the function in the target process. 471 /// 472 /// @param[in] args_addr_ref 473 /// The value of the void* parameter. 474 /// 475 /// @param[in] errors 476 /// The stream to write errors to. 477 /// 478 /// @param[in] stop_others 479 /// True if other threads should pause during execution. 480 /// 481 /// @param[in] unwind_on_error 482 /// True if the thread plan may simply be discarded if an error occurs. 483 /// 484 /// @return 485 /// A ThreadPlan for executing the function. 486 //------------------------------------------------------------------ 487 ThreadPlan * 488 GetThreadPlanToCallFunction (ExecutionContext &exe_ctx, 489 lldb::addr_t &args_addr_ref, 490 Stream &errors, 491 bool stop_others, 492 bool unwind_on_error = true, 493 bool ignore_breakpoints = true) 494 { 495 return ClangFunction::GetThreadPlanToCallFunction (exe_ctx, 496 m_jit_start_addr, 497 args_addr_ref, 498 errors, 499 stop_others, 500 unwind_on_error, 501 ignore_breakpoints); 502 } 503 504 //------------------------------------------------------------------ 505 /// Get the result of the function from its struct 506 /// 507 /// @param[in] exe_ctx 508 /// The execution context to retrieve the result from. 509 /// 510 /// @param[in] args_addr 511 /// The address of the argument struct. 512 /// 513 /// @param[in] ret_value 514 /// The value returned by the function. 515 /// 516 /// @return 517 /// True on success; false otherwise. 518 //------------------------------------------------------------------ 519 bool FetchFunctionResults (ExecutionContext &exe_ctx, 520 lldb::addr_t args_addr, 521 Value &ret_value); 522 523 //------------------------------------------------------------------ 524 /// Deallocate the arguments structure 525 /// 526 /// @param[in] exe_ctx 527 /// The execution context to insert the function and its arguments 528 /// into. 529 /// 530 /// @param[in] args_addr 531 /// The address of the argument struct. 532 //------------------------------------------------------------------ 533 void DeallocateFunctionResults (ExecutionContext &exe_ctx, 534 lldb::addr_t args_addr); 535 536 //------------------------------------------------------------------ 537 /// Interface for ClangExpression 538 //------------------------------------------------------------------ 539 540 //------------------------------------------------------------------ 541 /// Return the string that the parser should parse. Must be a full 542 /// translation unit. 543 //------------------------------------------------------------------ 544 const char * 545 Text () 546 { 547 return m_wrapper_function_text.c_str(); 548 } 549 550 //------------------------------------------------------------------ 551 /// Return the function name that should be used for executing the 552 /// expression. Text() should contain the definition of this 553 /// function. 554 //------------------------------------------------------------------ 555 const char * 556 FunctionName () 557 { 558 return m_wrapper_function_name.c_str(); 559 } 560 561 //------------------------------------------------------------------ 562 /// Return the object that the parser should use when resolving external 563 /// values. May be NULL if everything should be self-contained. 564 //------------------------------------------------------------------ 565 ClangExpressionDeclMap * 566 DeclMap () 567 { 568 return NULL; 569 } 570 571 //------------------------------------------------------------------ 572 /// Return the object that the parser should use when registering 573 /// local variables. May be NULL if the Expression doesn't care. 574 //------------------------------------------------------------------ 575 ClangExpressionVariableList * 576 LocalVariables () 577 { 578 return NULL; 579 } 580 581 //------------------------------------------------------------------ 582 /// Return the object that the parser should allow to access ASTs. 583 /// May be NULL if the ASTs do not need to be transformed. 584 /// 585 /// @param[in] passthrough 586 /// The ASTConsumer that the returned transformer should send 587 /// the ASTs to after transformation. 588 //------------------------------------------------------------------ 589 clang::ASTConsumer * 590 ASTTransformer (clang::ASTConsumer *passthrough); 591 592 //------------------------------------------------------------------ 593 /// Return true if validation code should be inserted into the 594 /// expression. 595 //------------------------------------------------------------------ 596 bool 597 NeedsValidation () 598 { 599 return false; 600 } 601 602 //------------------------------------------------------------------ 603 /// Return true if external variables in the expression should be 604 /// resolved. 605 //------------------------------------------------------------------ 606 bool 607 NeedsVariableResolution () 608 { 609 return false; 610 } 611 612private: 613 //------------------------------------------------------------------ 614 // For ClangFunction only 615 //------------------------------------------------------------------ 616 617 std::auto_ptr<ClangExpressionParser> m_parser; ///< The parser responsible for compiling the function. 618 619 Function *m_function_ptr; ///< The function we're going to call. May be NULL if we don't have debug info for the function. 620 Address m_function_addr; ///< If we don't have the FunctionSP, we at least need the address & return type. 621 lldb::clang_type_t m_function_return_qual_type; ///< The opaque clang qual type for the function return type. 622 ClangASTContext *m_clang_ast_context; ///< This is the clang_ast_context that we're getting types from the and value, and the function return the function pointer is NULL. 623 624 std::string m_wrapper_function_name; ///< The name of the wrapper function. 625 std::string m_wrapper_function_text; ///< The contents of the wrapper function. 626 std::string m_wrapper_struct_name; ///< The name of the struct that contains the target function address, arguments, and result. 627 std::list<lldb::addr_t> m_wrapper_args_addrs; ///< The addresses of the arguments to the wrapper function. 628 629 bool m_struct_valid; ///< True if the ASTStructExtractor has populated the variables below. 630 631 //------------------------------------------------------------------ 632 /// These values are populated by the ASTStructExtractor 633 size_t m_struct_size; ///< The size of the argument struct, in bytes. 634 std::vector<uint64_t> m_member_offsets; ///< The offset of each member in the struct, in bytes. 635 uint64_t m_return_size; ///< The size of the result variable, in bytes. 636 uint64_t m_return_offset; ///< The offset of the result variable in the struct, in bytes. 637 //------------------------------------------------------------------ 638 639 ValueList m_arg_values; ///< The default values of the arguments. 640 641 bool m_compiled; ///< True if the wrapper function has already been parsed. 642 bool m_JITted; ///< True if the wrapper function has already been JIT-compiled. 643}; 644 645} // Namespace lldb_private 646 647#endif // lldb_ClangFunction_h_ 648