1 /*
   2  * Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * Copyright (c) 2012, 2017 SAP AG. All rights reserved.
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This code is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 only, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This code is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * version 2 for more details (a copy is included in the LICENSE file that
  14  * accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License version
  17  * 2 along with this work; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  21  * or visit www.oracle.com if you need additional information or have any
  22  * questions.
  23  *
  24  */
  25 
  26 #include "precompiled.hpp"
  27 #include "interpreter/interpreter.hpp"
  28 #include "memory/resourceArea.hpp"
  29 #include "oops/markOop.hpp"
  30 #include "oops/method.hpp"
  31 #include "oops/oop.inline.hpp"
  32 #include "runtime/frame.inline.hpp"
  33 #include "runtime/handles.inline.hpp"
  34 #include "runtime/javaCalls.hpp"
  35 #include "runtime/monitorChunk.hpp"
  36 #include "runtime/signature.hpp"
  37 #include "runtime/stubCodeGenerator.hpp"
  38 #include "runtime/stubRoutines.hpp"
  39 #include "vmreg_ppc.inline.hpp"
  40 #ifdef COMPILER1
  41 #include "c1/c1_Runtime1.hpp"
  42 #include "runtime/vframeArray.hpp"
  43 #endif
  44 
  45 #ifdef ASSERT
  46 void RegisterMap::check_location_valid() {
  47 }
  48 #endif // ASSERT
  49 
  50 bool frame::safe_for_sender(JavaThread *thread) {
  51   bool safe = false;
  52   address sp = (address)_sp;
  53   address fp = (address)_fp;
  54   address unextended_sp = (address)_unextended_sp;
  55 
  56   // Consider stack guards when trying to determine "safe" stack pointers
  57   static size_t stack_guard_size = os::uses_stack_guard_pages() ?
  58     thread->stack_red_zone_size() + thread->stack_yellow_zone_size() : 0;
  59   size_t usable_stack_size = thread->stack_size() - stack_guard_size;
  60 
  61   // sp must be within the usable part of the stack (not in guards)
  62   bool sp_safe = (sp < thread->stack_base()) &&
  63                  (sp >= thread->stack_base() - usable_stack_size);
  64 
  65 
  66   if (!sp_safe) {
  67     return false;
  68   }
  69 
  70   // Unextended sp must be within the stack and above or equal sp
  71   bool unextended_sp_safe = (unextended_sp < thread->stack_base()) && (unextended_sp >= sp);
  72 
  73   if (!unextended_sp_safe) {
  74     return false;
  75   }
  76 
  77   // An fp must be within the stack and above (but not equal) sp.
  78   bool fp_safe = (fp <= thread->stack_base()) &&  (fp > sp);
  79   // an interpreter fp must be within the stack and above (but not equal) sp
  80   bool fp_interp_safe = (fp <= thread->stack_base()) &&  (fp > sp) &&
  81     ((fp - sp) >= (ijava_state_size + top_ijava_frame_abi_size));
  82 
  83   // We know sp/unextended_sp are safe, only fp is questionable here
  84 
  85   // If the current frame is known to the code cache then we can attempt to
  86   // to construct the sender and do some validation of it. This goes a long way
  87   // toward eliminating issues when we get in frame construction code
  88 
  89   if (_cb != NULL ){
  90     // Entry frame checks
  91     if (is_entry_frame()) {
  92       // An entry frame must have a valid fp.
  93       return fp_safe && is_entry_frame_valid(thread);
  94     }
  95 
  96     // Now check if the frame is complete and the test is
  97     // reliable. Unfortunately we can only check frame completeness for
  98     // runtime stubs and nmethods. Other generic buffer blobs are more
  99     // problematic so we just assume they are OK. Adapter blobs never have a
 100     // complete frame and are never OK
 101     if (!_cb->is_frame_complete_at(_pc)) {
 102       if (_cb->is_nmethod() || _cb->is_adapter_blob() || _cb->is_runtime_stub()) {
 103         return false;
 104       }
 105     }
 106 
 107     // Could just be some random pointer within the codeBlob.
 108     if (!_cb->code_contains(_pc)) {
 109       return false;
 110     }
 111 
 112     if (is_interpreted_frame() && !fp_interp_safe) {
 113       return false;
 114     }
 115 
 116     abi_minframe* sender_abi = (abi_minframe*) fp;
 117     intptr_t* sender_sp = (intptr_t*) fp;
 118     address   sender_pc = (address) sender_abi->lr;;
 119 
 120     // We must always be able to find a recognizable pc.
 121     CodeBlob* sender_blob = CodeCache::find_blob_unsafe(sender_pc);
 122     if (sender_blob == NULL) {
 123       return false;
 124     }
 125 
 126     // Could be a zombie method
 127     if (sender_blob->is_zombie() || sender_blob->is_unloaded()) {
 128       return false;
 129     }
 130 
 131     // It should be safe to construct the sender though it might not be valid.
 132 
 133     frame sender(sender_sp, sender_pc);
 134 
 135     // Do we have a valid fp?
 136     address sender_fp = (address) sender.fp();
 137 
 138     // sender_fp must be within the stack and above (but not
 139     // equal) current frame's fp.
 140     if (sender_fp > thread->stack_base() || sender_fp <= fp) {
 141         return false;
 142     }
 143 
 144     // If the potential sender is the interpreter then we can do some more checking.
 145     if (Interpreter::contains(sender_pc)) {
 146       return sender.is_interpreted_frame_valid(thread);
 147     }
 148 
 149     // Could just be some random pointer within the codeBlob.
 150     if (!sender.cb()->code_contains(sender_pc)) {
 151       return false;
 152     }
 153 
 154     // We should never be able to see an adapter if the current frame is something from code cache.
 155     if (sender_blob->is_adapter_blob()) {
 156       return false;
 157     }
 158 
 159     if (sender.is_entry_frame()) {
 160       return sender.is_entry_frame_valid(thread);
 161     }
 162 
 163     // Frame size is always greater than zero. If the sender frame size is zero or less,
 164     // something is really weird and we better give up.
 165     if (sender_blob->frame_size() <= 0) {
 166       return false;
 167     }
 168 
 169     return true;
 170   }
 171 
 172   // Must be native-compiled frame. Since sender will try and use fp to find
 173   // linkages it must be safe
 174 
 175   if (!fp_safe) {
 176     return false;
 177   }
 178 
 179   return true;
 180 }
 181 
 182 bool frame::is_interpreted_frame() const  {
 183   return Interpreter::contains(pc());
 184 }
 185 
 186 frame frame::sender_for_entry_frame(RegisterMap *map) const {
 187   assert(map != NULL, "map must be set");
 188   // Java frame called from C; skip all C frames and return top C
 189   // frame of that chunk as the sender.
 190   JavaFrameAnchor* jfa = entry_frame_call_wrapper()->anchor();
 191   assert(!entry_frame_is_first(), "next Java fp must be non zero");
 192   assert(jfa->last_Java_sp() > _sp, "must be above this frame on stack");
 193   map->clear();
 194   assert(map->include_argument_oops(), "should be set by clear");
 195 
 196   if (jfa->last_Java_pc() != NULL) {
 197     frame fr(jfa->last_Java_sp(), jfa->last_Java_pc());
 198     return fr;
 199   }
 200   // Last_java_pc is not set, if we come here from compiled code. The
 201   // constructor retrieves the PC from the stack.
 202   frame fr(jfa->last_Java_sp());
 203   return fr;
 204 }
 205 
 206 frame frame::sender_for_interpreter_frame(RegisterMap *map) const {
 207   // Pass callers initial_caller_sp as unextended_sp.
 208   return frame(sender_sp(), sender_pc(),
 209                CC_INTERP_ONLY((intptr_t*)((parent_ijava_frame_abi *)callers_abi())->initial_caller_sp)
 210                NOT_CC_INTERP((intptr_t*)get_ijava_state()->sender_sp)
 211                );
 212 }
 213 
 214 frame frame::sender_for_compiled_frame(RegisterMap *map) const {
 215   assert(map != NULL, "map must be set");
 216 
 217   // Frame owned by compiler.
 218   address pc = *compiled_sender_pc_addr(_cb);
 219   frame caller(compiled_sender_sp(_cb), pc);
 220 
 221   // Now adjust the map.
 222 
 223   // Get the rest.
 224   if (map->update_map()) {
 225     // Tell GC to use argument oopmaps for some runtime stubs that need it.
 226     map->set_include_argument_oops(_cb->caller_must_gc_arguments(map->thread()));
 227     if (_cb->oop_maps() != NULL) {
 228       OopMapSet::update_register_map(this, map);
 229     }
 230   }
 231 
 232   return caller;
 233 }
 234 
 235 intptr_t* frame::compiled_sender_sp(CodeBlob* cb) const {
 236   return sender_sp();
 237 }
 238 
 239 address* frame::compiled_sender_pc_addr(CodeBlob* cb) const {
 240   return sender_pc_addr();
 241 }
 242 
 243 frame frame::sender(RegisterMap* map) const {
 244   // Default is we do have to follow them. The sender_for_xxx will
 245   // update it accordingly.
 246   map->set_include_argument_oops(false);
 247 
 248   if (is_entry_frame())       return sender_for_entry_frame(map);
 249   if (is_interpreted_frame()) return sender_for_interpreter_frame(map);
 250   assert(_cb == CodeCache::find_blob(pc()),"Must be the same");
 251 
 252   if (_cb != NULL) {
 253     return sender_for_compiled_frame(map);
 254   }
 255   // Must be native-compiled frame, i.e. the marshaling code for native
 256   // methods that exists in the core system.
 257   return frame(sender_sp(), sender_pc());
 258 }
 259 
 260 void frame::patch_pc(Thread* thread, address pc) {
 261   if (TracePcPatching) {
 262     tty->print_cr("patch_pc at address " PTR_FORMAT " [" PTR_FORMAT " -> " PTR_FORMAT "]",
 263                   p2i(&((address*) _sp)[-1]), p2i(((address*) _sp)[-1]), p2i(pc));
 264   }
 265   own_abi()->lr = (uint64_t)pc;
 266   _cb = CodeCache::find_blob(pc);
 267   if (_cb != NULL && _cb->is_nmethod() && ((nmethod*)_cb)->is_deopt_pc(_pc)) {
 268     address orig = (((nmethod*)_cb)->get_original_pc(this));
 269     assert(orig == _pc, "expected original to be stored before patching");
 270     _deopt_state = is_deoptimized;
 271     // Leave _pc as is.
 272   } else {
 273     _deopt_state = not_deoptimized;
 274     _pc = pc;
 275   }
 276 }
 277 
 278 void frame::pd_gc_epilog() {
 279   if (is_interpreted_frame()) {
 280     // Set constant pool cache entry for interpreter.
 281     Method* m = interpreter_frame_method();
 282 
 283     *interpreter_frame_cpoolcache_addr() = m->constants()->cache();
 284   }
 285 }
 286 
 287 bool frame::is_interpreted_frame_valid(JavaThread* thread) const {
 288   // Is there anything to do?
 289   assert(is_interpreted_frame(), "Not an interpreted frame");
 290   return true;
 291 }
 292 
 293 BasicType frame::interpreter_frame_result(oop* oop_result, jvalue* value_result) {
 294   assert(is_interpreted_frame(), "interpreted frame expected");
 295   Method* method = interpreter_frame_method();
 296   BasicType type = method->result_type();
 297 
 298   if (method->is_native()) {
 299     // Prior to calling into the runtime to notify the method exit the possible
 300     // result value is saved into the interpreter frame.
 301 #ifdef CC_INTERP
 302     interpreterState istate = get_interpreterState();
 303     address lresult = (address)istate + in_bytes(BytecodeInterpreter::native_lresult_offset());
 304     address fresult = (address)istate + in_bytes(BytecodeInterpreter::native_fresult_offset());
 305 #else
 306     address lresult = (address)&(get_ijava_state()->lresult);
 307     address fresult = (address)&(get_ijava_state()->fresult);
 308 #endif
 309 
 310     switch (method->result_type()) {
 311       case T_OBJECT:
 312       case T_ARRAY: {
 313         *oop_result = JNIHandles::resolve(*(jobject*)lresult);
 314         break;
 315       }
 316       // We use std/stfd to store the values.
 317       case T_BOOLEAN : value_result->z = (jboolean) *(unsigned long*)lresult; break;
 318       case T_INT     : value_result->i = (jint)     *(long*)lresult;          break;
 319       case T_CHAR    : value_result->c = (jchar)    *(unsigned long*)lresult; break;
 320       case T_SHORT   : value_result->s = (jshort)   *(long*)lresult;          break;
 321       case T_BYTE    : value_result->z = (jbyte)    *(long*)lresult;          break;
 322       case T_LONG    : value_result->j = (jlong)    *(long*)lresult;          break;
 323       case T_FLOAT   : value_result->f = (jfloat)   *(double*)fresult;        break;
 324       case T_DOUBLE  : value_result->d = (jdouble)  *(double*)fresult;        break;
 325       case T_VOID    : /* Nothing to do */ break;
 326       default        : ShouldNotReachHere();
 327     }
 328   } else {
 329     intptr_t* tos_addr = interpreter_frame_tos_address();
 330     switch (method->result_type()) {
 331       case T_OBJECT:
 332       case T_ARRAY: {
 333         oop obj = *(oop*)tos_addr;
 334         assert(obj == NULL || Universe::heap()->is_in(obj), "sanity check");
 335         *oop_result = obj;
 336       }
 337       case T_BOOLEAN : value_result->z = (jboolean) *(jint*)tos_addr; break;
 338       case T_BYTE    : value_result->b = (jbyte) *(jint*)tos_addr; break;
 339       case T_CHAR    : value_result->c = (jchar) *(jint*)tos_addr; break;
 340       case T_SHORT   : value_result->s = (jshort) *(jint*)tos_addr; break;
 341       case T_INT     : value_result->i = *(jint*)tos_addr; break;
 342       case T_LONG    : value_result->j = *(jlong*)tos_addr; break;
 343       case T_FLOAT   : value_result->f = *(jfloat*)tos_addr; break;
 344       case T_DOUBLE  : value_result->d = *(jdouble*)tos_addr; break;
 345       case T_VOID    : /* Nothing to do */ break;
 346       default        : ShouldNotReachHere();
 347     }
 348   }
 349   return type;
 350 }
 351 
 352 #ifndef PRODUCT
 353 
 354 void frame::describe_pd(FrameValues& values, int frame_no) {
 355   if (is_interpreted_frame()) {
 356 #ifdef CC_INTERP
 357     interpreterState istate = get_interpreterState();
 358     values.describe(frame_no, (intptr_t*)istate, "istate");
 359     values.describe(frame_no, (intptr_t*)&(istate->_thread), " thread");
 360     values.describe(frame_no, (intptr_t*)&(istate->_bcp), " bcp");
 361     values.describe(frame_no, (intptr_t*)&(istate->_locals), " locals");
 362     values.describe(frame_no, (intptr_t*)&(istate->_constants), " constants");
 363     values.describe(frame_no, (intptr_t*)&(istate->_method), err_msg(" method = %s", istate->_method->name_and_sig_as_C_string()));
 364     values.describe(frame_no, (intptr_t*)&(istate->_mdx), " mdx");
 365     values.describe(frame_no, (intptr_t*)&(istate->_stack), " stack");
 366     values.describe(frame_no, (intptr_t*)&(istate->_msg), err_msg(" msg = %s", BytecodeInterpreter::C_msg(istate->_msg)));
 367     values.describe(frame_no, (intptr_t*)&(istate->_result), " result");
 368     values.describe(frame_no, (intptr_t*)&(istate->_prev_link), " prev_link");
 369     values.describe(frame_no, (intptr_t*)&(istate->_oop_temp), " oop_temp");
 370     values.describe(frame_no, (intptr_t*)&(istate->_stack_base), " stack_base");
 371     values.describe(frame_no, (intptr_t*)&(istate->_stack_limit), " stack_limit");
 372     values.describe(frame_no, (intptr_t*)&(istate->_monitor_base), " monitor_base");
 373     values.describe(frame_no, (intptr_t*)&(istate->_frame_bottom), " frame_bottom");
 374     values.describe(frame_no, (intptr_t*)&(istate->_last_Java_pc), " last_Java_pc");
 375     values.describe(frame_no, (intptr_t*)&(istate->_last_Java_fp), " last_Java_fp");
 376     values.describe(frame_no, (intptr_t*)&(istate->_last_Java_sp), " last_Java_sp");
 377     values.describe(frame_no, (intptr_t*)&(istate->_self_link), " self_link");
 378     values.describe(frame_no, (intptr_t*)&(istate->_native_fresult), " native_fresult");
 379     values.describe(frame_no, (intptr_t*)&(istate->_native_lresult), " native_lresult");
 380 #else
 381 #define DESCRIBE_ADDRESS(name) \
 382   values.describe(frame_no, (intptr_t*)&(get_ijava_state()->name), #name);
 383 
 384       DESCRIBE_ADDRESS(method);
 385       DESCRIBE_ADDRESS(locals);
 386       DESCRIBE_ADDRESS(monitors);
 387       DESCRIBE_ADDRESS(cpoolCache);
 388       DESCRIBE_ADDRESS(bcp);
 389       DESCRIBE_ADDRESS(esp);
 390       DESCRIBE_ADDRESS(mdx);
 391       DESCRIBE_ADDRESS(top_frame_sp);
 392       DESCRIBE_ADDRESS(sender_sp);
 393       DESCRIBE_ADDRESS(oop_tmp);
 394       DESCRIBE_ADDRESS(lresult);
 395       DESCRIBE_ADDRESS(fresult);
 396 #endif
 397   }
 398 }
 399 #endif
 400 
 401 void frame::adjust_unextended_sp() {
 402   // If we are returning to a compiled MethodHandle call site, the
 403   // saved_fp will in fact be a saved value of the unextended SP. The
 404   // simplest way to tell whether we are returning to such a call site
 405   // is as follows:
 406 
 407   if (is_compiled_frame() && false /*is_at_mh_callsite()*/) {  // TODO PPC port
 408     // If the sender PC is a deoptimization point, get the original
 409     // PC. For MethodHandle call site the unextended_sp is stored in
 410     // saved_fp.
 411     _unextended_sp = _fp - _cb->frame_size();
 412 
 413 #ifdef ASSERT
 414     nmethod *sender_nm = _cb->as_nmethod_or_null();
 415     assert(sender_nm && *_sp == *_unextended_sp, "backlink changed");
 416 
 417     intptr_t* sp = _unextended_sp;  // check if stack can be walked from here
 418     for (int x = 0; x < 5; ++x) {   // check up to a couple of backlinks
 419       intptr_t* prev_sp = *(intptr_t**)sp;
 420       if (prev_sp == 0) break;      // end of stack
 421       assert(prev_sp>sp, "broken stack");
 422       sp = prev_sp;
 423     }
 424 
 425     if (sender_nm->is_deopt_mh_entry(_pc)) { // checks for deoptimization
 426       address original_pc = sender_nm->get_original_pc(this);
 427       assert(sender_nm->insts_contains(original_pc), "original PC must be in nmethod");
 428       assert(sender_nm->is_method_handle_return(original_pc), "must be");
 429     }
 430 #endif
 431   }
 432 }
 433 
 434 intptr_t *frame::initial_deoptimization_info() {
 435   // unused... but returns fp() to minimize changes introduced by 7087445
 436   return fp();
 437 }
 438 
 439 #ifndef PRODUCT
 440 // This is a generic constructor which is only used by pns() in debug.cpp.
 441 frame::frame(void* sp, void* fp, void* pc) : _sp((intptr_t*)sp), _unextended_sp((intptr_t*)sp) {
 442   find_codeblob_and_set_pc_and_deopt_state((address)pc); // also sets _fp and adjusts _unextended_sp
 443 }
 444 #endif