1 /*
   2  * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_RUNTIME_FRAME_HPP
  26 #define SHARE_RUNTIME_FRAME_HPP
  27 
  28 #include "oops/method.hpp"
  29 #include "runtime/basicLock.hpp"
  30 #include "runtime/monitorChunk.hpp"
  31 #include "runtime/registerMap.hpp"
  32 #include "utilities/macros.hpp"
  33 #ifdef ZERO
  34 # include "stack_zero.hpp"
  35 #endif
  36 
  37 typedef class BytecodeInterpreter* interpreterState;
  38 
  39 class CodeBlob;
  40 class FrameValues;
  41 class vframeArray;
  42 class JavaCallWrapper;
  43 
  44 
  45 // A frame represents a physical stack frame (an activation).  Frames
  46 // can be C or Java frames, and the Java frames can be interpreted or
  47 // compiled.  In contrast, vframes represent source-level activations,
  48 // so that one physical frame can correspond to multiple source level
  49 // frames because of inlining.
  50 
  51 class frame {
  52  private:
  53   // Instance variables:
  54   intptr_t* _sp; // stack pointer (from Thread::last_Java_sp)
  55   address   _pc; // program counter (the next instruction after the call)
  56 
  57   CodeBlob* _cb; // CodeBlob that "owns" pc
  58   enum deopt_state {
  59     not_deoptimized,
  60     is_deoptimized,
  61     unknown
  62   };
  63 
  64   deopt_state _deopt_state;
  65 
  66  public:
  67   // Constructors
  68   frame();
  69 
  70 #ifndef PRODUCT
  71   // This is a generic constructor which is only used by pns() in debug.cpp.
  72   // pns (i.e. print native stack) uses this constructor to create a starting
  73   // frame for stack walking. The implementation of this constructor is platform
  74   // dependent (i.e. SPARC doesn't need an 'fp' argument an will ignore it) but
  75   // we want to keep the signature generic because pns() is shared code.
  76   frame(void* sp, void* fp, void* pc);
  77 #endif
  78 
  79   // Accessors
  80 
  81   // pc: Returns the pc at which this frame will continue normally.
  82   // It must point at the beginning of the next instruction to execute.
  83   address pc() const             { return _pc; }
  84 
  85   // This returns the pc that if you were in the debugger you'd see. Not
  86   // the idealized value in the frame object. This undoes the magic conversion
  87   // that happens for deoptimized frames. In addition it makes the value the
  88   // hardware would want to see in the native frame. The only user (at this point)
  89   // is deoptimization. It likely no one else should ever use it.
  90   address raw_pc() const;
  91 
  92   void set_pc( address   newpc );
  93 
  94   intptr_t* sp() const           { return _sp; }
  95   void set_sp( intptr_t* newsp ) { _sp = newsp; }
  96 
  97 
  98   CodeBlob* cb() const           { return _cb; }
  99 
 100   // patching operations
 101   void   patch_pc(Thread* thread, address pc);
 102 
 103   // Every frame needs to return a unique id which distinguishes it from all other frames.
 104   // For sparc and ia32 use sp. ia64 can have memory frames that are empty so multiple frames
 105   // will have identical sp values. For ia64 the bsp (fp) value will serve. No real frame
 106   // should have an id() of NULL so it is a distinguishing value for an unmatchable frame.
 107   // We also have relationals which allow comparing a frame to anoth frame's id() allow
 108   // us to distinguish younger (more recent activation) from older (less recent activations)
 109   // A NULL id is only valid when comparing for equality.
 110 
 111   intptr_t* id(void) const;
 112   bool is_younger(intptr_t* id) const;
 113   bool is_older(intptr_t* id) const;
 114 
 115   // testers
 116 
 117   // Compares for strict equality. Rarely used or needed.
 118   // It can return a different result than f1.id() == f2.id()
 119   bool equal(frame other) const;
 120 
 121   // type testers
 122   bool is_interpreted_frame()    const;
 123   bool is_java_frame()           const;
 124   bool is_entry_frame()          const;             // Java frame called from C?
 125   bool is_stub_frame()           const;
 126   bool is_ignored_frame()        const;
 127   bool is_native_frame()         const;
 128   bool is_runtime_frame()        const;
 129   bool is_compiled_frame()       const;
 130   bool is_safepoint_blob_frame() const;
 131   bool is_deoptimized_frame()    const;
 132 
 133   // testers
 134   bool is_first_frame() const; // oldest frame? (has no sender)
 135   bool is_first_java_frame() const;              // same for Java frame
 136 
 137   bool is_interpreted_frame_valid(JavaThread* thread) const;       // performs sanity checks on interpreted frames.
 138 
 139   // tells whether this frame is marked for deoptimization
 140   bool should_be_deoptimized() const;
 141 
 142   // tells whether this frame can be deoptimized
 143   bool can_be_deoptimized() const;
 144 
 145   // returns the frame size in stack slots
 146   int frame_size(RegisterMap* map) const;
 147 
 148   // returns the sending frame
 149   frame sender(RegisterMap* map) const;
 150 
 151   bool safe_for_sender(JavaThread *thread);
 152 
 153   // returns the sender, but skips conversion frames
 154   frame real_sender(RegisterMap* map) const;
 155 
 156   // returns the the sending Java frame, skipping any intermediate C frames
 157   // NB: receiver must not be first frame
 158   frame java_sender() const;
 159 
 160  private:
 161   // Helper methods for better factored code in frame::sender
 162   frame sender_for_compiled_frame(RegisterMap* map) const;
 163   frame sender_for_entry_frame(RegisterMap* map) const;
 164   frame sender_for_interpreter_frame(RegisterMap* map) const;
 165   frame sender_for_native_frame(RegisterMap* map) const;
 166 
 167   bool is_entry_frame_valid(JavaThread* thread) const;
 168 
 169   // All frames:
 170 
 171   // A low-level interface for vframes:
 172 
 173  public:
 174 
 175   intptr_t* addr_at(int index) const             { return &fp()[index];    }
 176   intptr_t  at(int index) const                  { return *addr_at(index); }
 177 
 178   // accessors for locals
 179   oop obj_at(int offset) const                   { return *obj_at_addr(offset);  }
 180   void obj_at_put(int offset, oop value)         { *obj_at_addr(offset) = value; }
 181 
 182   jint int_at(int offset) const                  { return *int_at_addr(offset);  }
 183   void int_at_put(int offset, jint value)        { *int_at_addr(offset) = value; }
 184 
 185   oop*      obj_at_addr(int offset) const        { return (oop*)     addr_at(offset); }
 186 
 187   oop*      adjusted_obj_at_addr(Method* method, int index) { return obj_at_addr(adjust_offset(method, index)); }
 188 
 189  private:
 190   jint*    int_at_addr(int offset) const         { return (jint*)    addr_at(offset); }
 191 
 192  public:
 193   // Link (i.e., the pointer to the previous frame)
 194   intptr_t* link() const;
 195 
 196   // Return address
 197   address  sender_pc() const;
 198 
 199   // Support for deoptimization
 200   void deoptimize(JavaThread* thread);
 201 
 202   // The frame's original SP, before any extension by an interpreted callee;
 203   // used for packing debug info into vframeArray objects and vframeArray lookup.
 204   intptr_t* unextended_sp() const;
 205 
 206   // returns the stack pointer of the calling frame
 207   intptr_t* sender_sp() const;
 208 
 209   // Returns the real 'frame pointer' for the current frame.
 210   // This is the value expected by the platform ABI when it defines a
 211   // frame pointer register. It may differ from the effective value of
 212   // the FP register when that register is used in the JVM for other
 213   // purposes (like compiled frames on some platforms).
 214   // On other platforms, it is defined so that the stack area used by
 215   // this frame goes from real_fp() to sp().
 216   intptr_t* real_fp() const;
 217 
 218   // Deoptimization info, if needed (platform dependent).
 219   // Stored in the initial_info field of the unroll info, to be used by
 220   // the platform dependent deoptimization blobs.
 221   intptr_t *initial_deoptimization_info();
 222 
 223   // Interpreter frames:
 224 
 225  private:
 226   intptr_t** interpreter_frame_locals_addr() const;
 227   intptr_t*  interpreter_frame_bcp_addr() const;
 228   intptr_t*  interpreter_frame_mdp_addr() const;
 229 
 230  public:
 231   // Locals
 232 
 233   // The _at version returns a pointer because the address is used for GC.
 234   intptr_t* interpreter_frame_local_at(int index) const;
 235 
 236   void interpreter_frame_set_locals(intptr_t* locs);
 237 
 238   // byte code index
 239   jint interpreter_frame_bci() const;
 240 
 241   // byte code pointer
 242   address interpreter_frame_bcp() const;
 243   void    interpreter_frame_set_bcp(address bcp);
 244 
 245   // method data pointer
 246   address interpreter_frame_mdp() const;
 247   void    interpreter_frame_set_mdp(address dp);
 248 
 249   // Find receiver out of caller's (compiled) argument list
 250   oop retrieve_receiver(RegisterMap *reg_map);
 251 
 252   // Return the monitor owner and BasicLock for compiled synchronized
 253   // native methods so that biased locking can revoke the receiver's
 254   // bias if necessary.  This is also used by JVMTI's GetLocalInstance method
 255   // (via VM_GetReceiver) to retrieve the receiver from a native wrapper frame.
 256   BasicLock* get_native_monitor();
 257   oop        get_native_receiver();
 258 
 259   // Find receiver for an invoke when arguments are just pushed on stack (i.e., callee stack-frame is
 260   // not setup)
 261   oop interpreter_callee_receiver(Symbol* signature)     { return *interpreter_callee_receiver_addr(signature); }
 262 
 263 
 264   oop* interpreter_callee_receiver_addr(Symbol* signature);
 265 
 266 
 267   // expression stack (may go up or down, direction == 1 or -1)
 268  public:
 269   intptr_t* interpreter_frame_expression_stack() const;
 270 
 271   // The _at version returns a pointer because the address is used for GC.
 272   intptr_t* interpreter_frame_expression_stack_at(jint offset) const;
 273 
 274   // top of expression stack
 275   intptr_t* interpreter_frame_tos_at(jint offset) const;
 276   intptr_t* interpreter_frame_tos_address() const;
 277 
 278 
 279   jint  interpreter_frame_expression_stack_size() const;
 280 
 281   intptr_t* interpreter_frame_sender_sp() const;
 282 
 283 #ifndef CC_INTERP
 284   // template based interpreter deoptimization support
 285   void  set_interpreter_frame_sender_sp(intptr_t* sender_sp);
 286   void interpreter_frame_set_monitor_end(BasicObjectLock* value);
 287 #endif // CC_INTERP
 288 
 289   // Address of the temp oop in the frame. Needed as GC root.
 290   oop* interpreter_frame_temp_oop_addr() const;
 291 
 292   // BasicObjectLocks:
 293   //
 294   // interpreter_frame_monitor_begin is higher in memory than interpreter_frame_monitor_end
 295   // Interpreter_frame_monitor_begin points to one element beyond the oldest one,
 296   // interpreter_frame_monitor_end   points to the youngest one, or if there are none,
 297   //                                 it points to one beyond where the first element will be.
 298   // interpreter_frame_monitor_size  reports the allocation size of a monitor in the interpreter stack.
 299   //                                 this value is >= BasicObjectLock::size(), and may be rounded up
 300 
 301   BasicObjectLock* interpreter_frame_monitor_begin() const;
 302   BasicObjectLock* interpreter_frame_monitor_end()   const;
 303   BasicObjectLock* next_monitor_in_interpreter_frame(BasicObjectLock* current) const;
 304   BasicObjectLock* previous_monitor_in_interpreter_frame(BasicObjectLock* current) const;
 305   static int interpreter_frame_monitor_size();
 306 
 307   void interpreter_frame_verify_monitor(BasicObjectLock* value) const;
 308 
 309   // Return/result value from this interpreter frame
 310   // If the method return type is T_OBJECT or T_ARRAY populates oop_result
 311   // For other (non-T_VOID) the appropriate field in the jvalue is populated
 312   // with the result value.
 313   // Should only be called when at method exit when the method is not
 314   // exiting due to an exception.
 315   BasicType interpreter_frame_result(oop* oop_result, jvalue* value_result);
 316 
 317  public:
 318   // Method & constant pool cache
 319   Method* interpreter_frame_method() const;
 320   void interpreter_frame_set_method(Method* method);
 321   Method** interpreter_frame_method_addr() const;
 322   ConstantPoolCache** interpreter_frame_cache_addr() const;
 323   oop* interpreter_frame_mirror_addr() const;
 324 
 325   void interpreter_frame_set_mirror(oop mirror);
 326 
 327  public:
 328   // Entry frames
 329   JavaCallWrapper* entry_frame_call_wrapper() const { return *entry_frame_call_wrapper_addr(); }
 330   JavaCallWrapper* entry_frame_call_wrapper_if_safe(JavaThread* thread) const;
 331   JavaCallWrapper** entry_frame_call_wrapper_addr() const;
 332   intptr_t* entry_frame_argument_at(int offset) const;
 333 
 334   // tells whether there is another chunk of Delta stack above
 335   bool entry_frame_is_first() const;
 336 
 337   // Safepoints
 338 
 339  public:
 340   oop saved_oop_result(RegisterMap* map) const;
 341   void set_saved_oop_result(RegisterMap* map, oop obj);
 342 
 343   // For debugging
 344  private:
 345   const char* print_name() const;
 346 
 347   void describe_pd(FrameValues& values, int frame_no);
 348 
 349  public:
 350   void print_value() const { print_value_on(tty,NULL); }
 351   void print_value_on(outputStream* st, JavaThread *thread) const;
 352   void print_on(outputStream* st) const;
 353   void interpreter_frame_print_on(outputStream* st) const;
 354   void print_on_error(outputStream* st, char* buf, int buflen, bool verbose = false) const;
 355   static void print_C_frame(outputStream* st, char* buf, int buflen, address pc);
 356 
 357   // Add annotated descriptions of memory locations belonging to this frame to values
 358   void describe(FrameValues& values, int frame_no);
 359 
 360   // Conversion from a VMReg to physical stack location
 361   oop* oopmapreg_to_location(VMReg reg, const RegisterMap* reg_map) const;
 362 
 363   // Oops-do's
 364   void oops_compiled_arguments_do(Symbol* signature, bool has_receiver, bool has_appendix, const RegisterMap* reg_map, OopClosure* f);
 365   void oops_interpreted_do(OopClosure* f, const RegisterMap* map, bool query_oop_map_cache = true);
 366 
 367  private:
 368   void oops_interpreted_arguments_do(Symbol* signature, bool has_receiver, OopClosure* f);
 369 
 370   // Iteration of oops
 371   void oops_do_internal(OopClosure* f, CodeBlobClosure* cf, RegisterMap* map, bool use_interpreter_oop_map_cache);
 372   void oops_entry_do(OopClosure* f, const RegisterMap* map);
 373   void oops_code_blob_do(OopClosure* f, CodeBlobClosure* cf, const RegisterMap* map);
 374   int adjust_offset(Method* method, int index); // helper for above fn
 375  public:
 376   // Memory management
 377   void oops_do(OopClosure* f, CodeBlobClosure* cf, RegisterMap* map) { oops_do_internal(f, cf, map, true); }
 378   void nmethods_do(CodeBlobClosure* cf);
 379 
 380   // RedefineClasses support for finding live interpreted methods on the stack
 381   void metadata_do(MetadataClosure* f);
 382 
 383   // Verification
 384   void verify(const RegisterMap* map);
 385   static bool verify_return_pc(address x);
 386   // Usage:
 387   // assert(frame::verify_return_pc(return_address), "must be a return pc");
 388 
 389   NOT_PRODUCT(void pd_ps();)  // platform dependent frame printing
 390 
 391 #include CPU_HEADER(frame)
 392 
 393 };
 394 
 395 #ifndef PRODUCT
 396 // A simple class to describe a location on the stack
 397 class FrameValue {
 398  public:
 399   intptr_t* location;
 400   char* description;
 401   int owner;
 402   int priority;
 403 
 404   FrameValue() {
 405     location = NULL;
 406     description = NULL;
 407     owner = -1;
 408     priority = 0;
 409   }
 410 
 411 };
 412 
 413 
 414 // A collection of described stack values that can print a symbolic
 415 // description of the stack memory.  Interpreter frame values can be
 416 // in the caller frames so all the values are collected first and then
 417 // sorted before being printed.
 418 class FrameValues {
 419  private:
 420   GrowableArray<FrameValue> _values;
 421 
 422   static int compare(FrameValue* a, FrameValue* b) {
 423     if (a->location == b->location) {
 424       return a->priority - b->priority;
 425     }
 426     return a->location - b->location;
 427   }
 428 
 429  public:
 430   // Used by frame functions to describe locations.
 431   void describe(int owner, intptr_t* location, const char* description, int priority = 0);
 432 
 433 #ifdef ASSERT
 434   void validate();
 435 #endif
 436   void print(JavaThread* thread);
 437 };
 438 
 439 #endif
 440 
 441 //
 442 // StackFrameStream iterates through the frames of a thread starting from
 443 // top most frame. It automatically takes care of updating the location of
 444 // all (callee-saved) registers. Notice: If a thread is stopped at
 445 // a safepoint, all registers are saved, not only the callee-saved ones.
 446 //
 447 // Use:
 448 //
 449 //   for(StackFrameStream fst(thread); !fst.is_done(); fst.next()) {
 450 //     ...
 451 //   }
 452 //
 453 class StackFrameStream : public StackObj {
 454  private:
 455   frame       _fr;
 456   RegisterMap _reg_map;
 457   bool        _is_done;
 458  public:
 459    StackFrameStream(JavaThread *thread, bool update = true);
 460 
 461   // Iteration
 462   inline bool is_done();
 463   void next()                     { if (!_is_done) _fr = _fr.sender(&_reg_map); }
 464 
 465   // Query
 466   frame *current()                { return &_fr; }
 467   RegisterMap* register_map()     { return &_reg_map; }
 468 };
 469 
 470 #endif // SHARE_RUNTIME_FRAME_HPP