src/share/vm/ci/bcEscapeAnalyzer.cpp

Mon, 23 Aug 2010 09:09:36 -0700

author
kvn
date
Mon, 23 Aug 2010 09:09:36 -0700
changeset 2102
53dbe853fb3a
parent 2003
8099e71601df
child 2314
f95d63e2154a
permissions
-rw-r--r--

6896381: CTW fails share/vm/ci/bcEscapeAnalyzer.cpp:99, assert(_stack_height < _max_stack,"stack overflow")
Summary: Check constant Tag type instead of calling get_constant().
Reviewed-by: never

     1 /*
     2  * Copyright (c) 2005, 2009, 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  */
    26 #include "incls/_precompiled.incl"
    27 #include "incls/_bcEscapeAnalyzer.cpp.incl"
    30 #ifndef PRODUCT
    31   #define TRACE_BCEA(level, code)                                            \
    32     if (EstimateArgEscape && BCEATraceLevel >= level) {                        \
    33       code;                                                                  \
    34     }
    35 #else
    36   #define TRACE_BCEA(level, code)
    37 #endif
    39 // Maintain a map of which aguments a local variable or
    40 // stack slot may contain.  In addition to tracking
    41 // arguments, it tracks two special values, "allocated"
    42 // which represents any object allocated in the current
    43 // method, and "unknown" which is any other object.
    44 // Up to 30 arguments are handled, with the last one
    45 // representing summary information for any extra arguments
    46 class BCEscapeAnalyzer::ArgumentMap {
    47   uint  _bits;
    48   enum {MAXBIT = 29,
    49         ALLOCATED = 1,
    50         UNKNOWN = 2};
    52   uint int_to_bit(uint e) const {
    53     if (e > MAXBIT)
    54       e = MAXBIT;
    55     return (1 << (e + 2));
    56   }
    58 public:
    59   ArgumentMap()                         { _bits = 0;}
    60   void set_bits(uint bits)              { _bits = bits;}
    61   uint get_bits() const                 { return _bits;}
    62   void clear()                          { _bits = 0;}
    63   void set_all()                        { _bits = ~0u; }
    64   bool is_empty() const                 { return _bits == 0; }
    65   bool contains(uint var) const         { return (_bits & int_to_bit(var)) != 0; }
    66   bool is_singleton(uint var) const     { return (_bits == int_to_bit(var)); }
    67   bool contains_unknown() const         { return (_bits & UNKNOWN) != 0; }
    68   bool contains_allocated() const       { return (_bits & ALLOCATED) != 0; }
    69   bool contains_vars() const            { return (_bits & (((1 << MAXBIT) -1) << 2)) != 0; }
    70   void set(uint var)                    { _bits = int_to_bit(var); }
    71   void add(uint var)                    { _bits |= int_to_bit(var); }
    72   void add_unknown()                    { _bits = UNKNOWN; }
    73   void add_allocated()                  { _bits = ALLOCATED; }
    74   void set_union(const ArgumentMap &am)     { _bits |= am._bits; }
    75   void set_intersect(const ArgumentMap &am) { _bits |= am._bits; }
    76   void set_difference(const ArgumentMap &am) { _bits &=  ~am._bits; }
    77   void operator=(const ArgumentMap &am) { _bits = am._bits; }
    78   bool operator==(const ArgumentMap &am) { return _bits == am._bits; }
    79   bool operator!=(const ArgumentMap &am) { return _bits != am._bits; }
    80 };
    82 class BCEscapeAnalyzer::StateInfo {
    83 public:
    84   ArgumentMap *_vars;
    85   ArgumentMap *_stack;
    86   short _stack_height;
    87   short _max_stack;
    88   bool _initialized;
    89   ArgumentMap empty_map;
    91   StateInfo() {
    92     empty_map.clear();
    93   }
    95   ArgumentMap raw_pop()  { guarantee(_stack_height > 0, "stack underflow"); return _stack[--_stack_height]; }
    96   ArgumentMap  apop()    { return raw_pop(); }
    97   void spop()            { raw_pop(); }
    98   void lpop()            { spop(); spop(); }
    99   void raw_push(ArgumentMap i)   { guarantee(_stack_height < _max_stack, "stack overflow"); _stack[_stack_height++] = i; }
   100   void apush(ArgumentMap i)      { raw_push(i); }
   101   void spush()           { raw_push(empty_map); }
   102   void lpush()           { spush(); spush(); }
   104 };
   106 void BCEscapeAnalyzer::set_returned(ArgumentMap vars) {
   107   for (int i = 0; i < _arg_size; i++) {
   108     if (vars.contains(i))
   109       _arg_returned.set(i);
   110   }
   111   _return_local = _return_local && !(vars.contains_unknown() || vars.contains_allocated());
   112   _return_allocated = _return_allocated && vars.contains_allocated() && !(vars.contains_unknown() || vars.contains_vars());
   113 }
   115 // return true if any element of vars is an argument
   116 bool BCEscapeAnalyzer::is_argument(ArgumentMap vars) {
   117   for (int i = 0; i < _arg_size; i++) {
   118     if (vars.contains(i))
   119       return true;
   120   }
   121   return false;
   122 }
   124 // return true if any element of vars is an arg_stack argument
   125 bool BCEscapeAnalyzer::is_arg_stack(ArgumentMap vars){
   126   if (_conservative)
   127     return true;
   128   for (int i = 0; i < _arg_size; i++) {
   129     if (vars.contains(i) && _arg_stack.test(i))
   130       return true;
   131   }
   132   return false;
   133 }
   135 void BCEscapeAnalyzer::clear_bits(ArgumentMap vars, VectorSet &bm) {
   136   for (int i = 0; i < _arg_size; i++) {
   137     if (vars.contains(i)) {
   138       bm >>= i;
   139     }
   140   }
   141 }
   143 void BCEscapeAnalyzer::set_method_escape(ArgumentMap vars) {
   144   clear_bits(vars, _arg_local);
   145 }
   147 void BCEscapeAnalyzer::set_global_escape(ArgumentMap vars) {
   148   clear_bits(vars, _arg_local);
   149   clear_bits(vars, _arg_stack);
   150   if (vars.contains_allocated())
   151     _allocated_escapes = true;
   152 }
   154 void BCEscapeAnalyzer::set_dirty(ArgumentMap vars) {
   155   clear_bits(vars, _dirty);
   156 }
   158 void BCEscapeAnalyzer::set_modified(ArgumentMap vars, int offs, int size) {
   160   for (int i = 0; i < _arg_size; i++) {
   161     if (vars.contains(i)) {
   162       set_arg_modified(i, offs, size);
   163     }
   164   }
   165   if (vars.contains_unknown())
   166     _unknown_modified = true;
   167 }
   169 bool BCEscapeAnalyzer::is_recursive_call(ciMethod* callee) {
   170   for (BCEscapeAnalyzer* scope = this; scope != NULL; scope = scope->_parent) {
   171     if (scope->method() == callee) {
   172       return true;
   173     }
   174   }
   175   return false;
   176 }
   178 bool BCEscapeAnalyzer::is_arg_modified(int arg, int offset, int size_in_bytes) {
   179   if (offset == OFFSET_ANY)
   180     return _arg_modified[arg] != 0;
   181   assert(arg >= 0 && arg < _arg_size, "must be an argument.");
   182   bool modified = false;
   183   int l = offset / HeapWordSize;
   184   int h = round_to(offset + size_in_bytes, HeapWordSize) / HeapWordSize;
   185   if (l > ARG_OFFSET_MAX)
   186     l = ARG_OFFSET_MAX;
   187   if (h > ARG_OFFSET_MAX+1)
   188     h = ARG_OFFSET_MAX + 1;
   189   for (int i = l; i < h; i++) {
   190     modified = modified || (_arg_modified[arg] & (1 << i)) != 0;
   191   }
   192   return modified;
   193 }
   195 void BCEscapeAnalyzer::set_arg_modified(int arg, int offset, int size_in_bytes) {
   196   if (offset == OFFSET_ANY) {
   197     _arg_modified[arg] =  (uint) -1;
   198     return;
   199   }
   200   assert(arg >= 0 && arg < _arg_size, "must be an argument.");
   201   int l = offset / HeapWordSize;
   202   int h = round_to(offset + size_in_bytes, HeapWordSize) / HeapWordSize;
   203   if (l > ARG_OFFSET_MAX)
   204     l = ARG_OFFSET_MAX;
   205   if (h > ARG_OFFSET_MAX+1)
   206     h = ARG_OFFSET_MAX + 1;
   207   for (int i = l; i < h; i++) {
   208     _arg_modified[arg] |= (1 << i);
   209   }
   210 }
   212 void BCEscapeAnalyzer::invoke(StateInfo &state, Bytecodes::Code code, ciMethod* target, ciKlass* holder) {
   213   int i;
   215   // retrieve information about the callee
   216   ciInstanceKlass* klass = target->holder();
   217   ciInstanceKlass* calling_klass = method()->holder();
   218   ciInstanceKlass* callee_holder = ciEnv::get_instance_klass_for_declared_method_holder(holder);
   219   ciInstanceKlass* actual_recv = callee_holder;
   221   // some methods are obviously bindable without any type checks so
   222   // convert them directly to an invokespecial.
   223   if (target->is_loaded() && !target->is_abstract() &&
   224       target->can_be_statically_bound() && code == Bytecodes::_invokevirtual) {
   225     code = Bytecodes::_invokespecial;
   226   }
   228   // compute size of arguments
   229   int arg_size = target->arg_size();
   230   if (!target->is_loaded() && code == Bytecodes::_invokestatic) {
   231     arg_size--;
   232   }
   233   int arg_base = MAX2(state._stack_height - arg_size, 0);
   235   // direct recursive calls are skipped if they can be bound statically without introducing
   236   // dependencies and if parameters are passed at the same position as in the current method
   237   // other calls are skipped if there are no unescaped arguments passed to them
   238   bool directly_recursive = (method() == target) &&
   239                (code != Bytecodes::_invokevirtual || target->is_final_method() || state._stack[arg_base] .is_empty());
   241   // check if analysis of callee can safely be skipped
   242   bool skip_callee = true;
   243   for (i = state._stack_height - 1; i >= arg_base && skip_callee; i--) {
   244     ArgumentMap arg = state._stack[i];
   245     skip_callee = !is_argument(arg) || !is_arg_stack(arg) || (directly_recursive && arg.is_singleton(i - arg_base));
   246   }
   247   if (skip_callee) {
   248     TRACE_BCEA(3, tty->print_cr("[EA] skipping method %s::%s", holder->name()->as_utf8(), target->name()->as_utf8()));
   249     for (i = 0; i < arg_size; i++) {
   250       set_method_escape(state.raw_pop());
   251     }
   252     _unknown_modified = true;  // assume the worst since we don't analyze the called method
   253     return;
   254   }
   256   // determine actual method (use CHA if necessary)
   257   ciMethod* inline_target = NULL;
   258   if (target->is_loaded() && klass->is_loaded()
   259       && (klass->is_initialized() || klass->is_interface() && target->holder()->is_initialized())
   260       && target->will_link(klass, callee_holder, code)) {
   261     if (code == Bytecodes::_invokestatic
   262         || code == Bytecodes::_invokespecial
   263         || code == Bytecodes::_invokevirtual && target->is_final_method()) {
   264       inline_target = target;
   265     } else {
   266       inline_target = target->find_monomorphic_target(calling_klass, callee_holder, actual_recv);
   267     }
   268   }
   270   if (inline_target != NULL && !is_recursive_call(inline_target)) {
   271     // analyze callee
   272     BCEscapeAnalyzer analyzer(inline_target, this);
   274     // adjust escape state of actual parameters
   275     bool must_record_dependencies = false;
   276     for (i = arg_size - 1; i >= 0; i--) {
   277       ArgumentMap arg = state.raw_pop();
   278       if (!is_argument(arg))
   279         continue;
   280       for (int j = 0; j < _arg_size; j++) {
   281         if (arg.contains(j)) {
   282           _arg_modified[j] |= analyzer._arg_modified[i];
   283         }
   284       }
   285       if (!is_arg_stack(arg)) {
   286         // arguments have already been recognized as escaping
   287       } else if (analyzer.is_arg_stack(i) && !analyzer.is_arg_returned(i)) {
   288         set_method_escape(arg);
   289         must_record_dependencies = true;
   290       } else {
   291         set_global_escape(arg);
   292       }
   293     }
   294     _unknown_modified = _unknown_modified || analyzer.has_non_arg_side_affects();
   296     // record dependencies if at least one parameter retained stack-allocatable
   297     if (must_record_dependencies) {
   298       if (code == Bytecodes::_invokeinterface || code == Bytecodes::_invokevirtual && !target->is_final_method()) {
   299         _dependencies.append(actual_recv);
   300         _dependencies.append(inline_target);
   301       }
   302       _dependencies.appendAll(analyzer.dependencies());
   303     }
   304   } else {
   305     TRACE_BCEA(1, tty->print_cr("[EA] virtual method %s is not monomorphic.",
   306                                 target->name()->as_utf8()));
   307     // conservatively mark all actual parameters as escaping globally
   308     for (i = 0; i < arg_size; i++) {
   309       ArgumentMap arg = state.raw_pop();
   310       if (!is_argument(arg))
   311         continue;
   312       set_modified(arg, OFFSET_ANY, type2size[T_INT]*HeapWordSize);
   313       set_global_escape(arg);
   314     }
   315     _unknown_modified = true;  // assume the worst since we don't know the called method
   316   }
   317 }
   319 bool BCEscapeAnalyzer::contains(uint arg_set1, uint arg_set2) {
   320   return ((~arg_set1) | arg_set2) == 0;
   321 }
   324 void BCEscapeAnalyzer::iterate_one_block(ciBlock *blk, StateInfo &state, GrowableArray<ciBlock *> &successors) {
   326   blk->set_processed();
   327   ciBytecodeStream s(method());
   328   int limit_bci = blk->limit_bci();
   329   bool fall_through = false;
   330   ArgumentMap allocated_obj;
   331   allocated_obj.add_allocated();
   332   ArgumentMap unknown_obj;
   333   unknown_obj.add_unknown();
   334   ArgumentMap empty_map;
   336   s.reset_to_bci(blk->start_bci());
   337   while (s.next() != ciBytecodeStream::EOBC() && s.cur_bci() < limit_bci) {
   338     fall_through = true;
   339     switch (s.cur_bc()) {
   340       case Bytecodes::_nop:
   341         break;
   342       case Bytecodes::_aconst_null:
   343         state.apush(empty_map);
   344         break;
   345       case Bytecodes::_iconst_m1:
   346       case Bytecodes::_iconst_0:
   347       case Bytecodes::_iconst_1:
   348       case Bytecodes::_iconst_2:
   349       case Bytecodes::_iconst_3:
   350       case Bytecodes::_iconst_4:
   351       case Bytecodes::_iconst_5:
   352       case Bytecodes::_fconst_0:
   353       case Bytecodes::_fconst_1:
   354       case Bytecodes::_fconst_2:
   355       case Bytecodes::_bipush:
   356       case Bytecodes::_sipush:
   357         state.spush();
   358         break;
   359       case Bytecodes::_lconst_0:
   360       case Bytecodes::_lconst_1:
   361       case Bytecodes::_dconst_0:
   362       case Bytecodes::_dconst_1:
   363         state.lpush();
   364         break;
   365       case Bytecodes::_ldc:
   366       case Bytecodes::_ldc_w:
   367       case Bytecodes::_ldc2_w:
   368       {
   369         // Avoid calling get_constant() which will try to allocate
   370         // unloaded constant. We need only constant's type.
   371         int index = s.get_constant_pool_index();
   372         constantTag tag = s.get_constant_pool_tag(index);
   373         if (tag.is_long() || tag.is_double()) {
   374           // Only longs and doubles use 2 stack slots.
   375           state.lpush();
   376         } else {
   377           state.spush();
   378         }
   379         break;
   380       }
   381       case Bytecodes::_aload:
   382         state.apush(state._vars[s.get_index()]);
   383         break;
   384       case Bytecodes::_iload:
   385       case Bytecodes::_fload:
   386       case Bytecodes::_iload_0:
   387       case Bytecodes::_iload_1:
   388       case Bytecodes::_iload_2:
   389       case Bytecodes::_iload_3:
   390       case Bytecodes::_fload_0:
   391       case Bytecodes::_fload_1:
   392       case Bytecodes::_fload_2:
   393       case Bytecodes::_fload_3:
   394         state.spush();
   395         break;
   396       case Bytecodes::_lload:
   397       case Bytecodes::_dload:
   398       case Bytecodes::_lload_0:
   399       case Bytecodes::_lload_1:
   400       case Bytecodes::_lload_2:
   401       case Bytecodes::_lload_3:
   402       case Bytecodes::_dload_0:
   403       case Bytecodes::_dload_1:
   404       case Bytecodes::_dload_2:
   405       case Bytecodes::_dload_3:
   406         state.lpush();
   407         break;
   408       case Bytecodes::_aload_0:
   409         state.apush(state._vars[0]);
   410         break;
   411       case Bytecodes::_aload_1:
   412         state.apush(state._vars[1]);
   413         break;
   414       case Bytecodes::_aload_2:
   415         state.apush(state._vars[2]);
   416         break;
   417       case Bytecodes::_aload_3:
   418         state.apush(state._vars[3]);
   419         break;
   420       case Bytecodes::_iaload:
   421       case Bytecodes::_faload:
   422       case Bytecodes::_baload:
   423       case Bytecodes::_caload:
   424       case Bytecodes::_saload:
   425         state.spop();
   426         set_method_escape(state.apop());
   427         state.spush();
   428         break;
   429       case Bytecodes::_laload:
   430       case Bytecodes::_daload:
   431         state.spop();
   432         set_method_escape(state.apop());
   433         state.lpush();
   434         break;
   435       case Bytecodes::_aaload:
   436         { state.spop();
   437           ArgumentMap array = state.apop();
   438           set_method_escape(array);
   439           state.apush(unknown_obj);
   440           set_dirty(array);
   441         }
   442         break;
   443       case Bytecodes::_istore:
   444       case Bytecodes::_fstore:
   445       case Bytecodes::_istore_0:
   446       case Bytecodes::_istore_1:
   447       case Bytecodes::_istore_2:
   448       case Bytecodes::_istore_3:
   449       case Bytecodes::_fstore_0:
   450       case Bytecodes::_fstore_1:
   451       case Bytecodes::_fstore_2:
   452       case Bytecodes::_fstore_3:
   453         state.spop();
   454         break;
   455       case Bytecodes::_lstore:
   456       case Bytecodes::_dstore:
   457       case Bytecodes::_lstore_0:
   458       case Bytecodes::_lstore_1:
   459       case Bytecodes::_lstore_2:
   460       case Bytecodes::_lstore_3:
   461       case Bytecodes::_dstore_0:
   462       case Bytecodes::_dstore_1:
   463       case Bytecodes::_dstore_2:
   464       case Bytecodes::_dstore_3:
   465         state.lpop();
   466         break;
   467       case Bytecodes::_astore:
   468         state._vars[s.get_index()] = state.apop();
   469         break;
   470       case Bytecodes::_astore_0:
   471         state._vars[0] = state.apop();
   472         break;
   473       case Bytecodes::_astore_1:
   474         state._vars[1] = state.apop();
   475         break;
   476       case Bytecodes::_astore_2:
   477         state._vars[2] = state.apop();
   478         break;
   479       case Bytecodes::_astore_3:
   480         state._vars[3] = state.apop();
   481         break;
   482       case Bytecodes::_iastore:
   483       case Bytecodes::_fastore:
   484       case Bytecodes::_bastore:
   485       case Bytecodes::_castore:
   486       case Bytecodes::_sastore:
   487       {
   488         state.spop();
   489         state.spop();
   490         ArgumentMap arr = state.apop();
   491         set_method_escape(arr);
   492         set_modified(arr, OFFSET_ANY, type2size[T_INT]*HeapWordSize);
   493         break;
   494       }
   495       case Bytecodes::_lastore:
   496       case Bytecodes::_dastore:
   497       {
   498         state.lpop();
   499         state.spop();
   500         ArgumentMap arr = state.apop();
   501         set_method_escape(arr);
   502         set_modified(arr, OFFSET_ANY, type2size[T_LONG]*HeapWordSize);
   503         break;
   504       }
   505       case Bytecodes::_aastore:
   506       {
   507         set_global_escape(state.apop());
   508         state.spop();
   509         ArgumentMap arr = state.apop();
   510         set_modified(arr, OFFSET_ANY, type2size[T_OBJECT]*HeapWordSize);
   511         break;
   512       }
   513       case Bytecodes::_pop:
   514         state.raw_pop();
   515         break;
   516       case Bytecodes::_pop2:
   517         state.raw_pop();
   518         state.raw_pop();
   519         break;
   520       case Bytecodes::_dup:
   521         { ArgumentMap w1 = state.raw_pop();
   522           state.raw_push(w1);
   523           state.raw_push(w1);
   524         }
   525         break;
   526       case Bytecodes::_dup_x1:
   527         { ArgumentMap w1 = state.raw_pop();
   528           ArgumentMap w2 = state.raw_pop();
   529           state.raw_push(w1);
   530           state.raw_push(w2);
   531           state.raw_push(w1);
   532         }
   533         break;
   534       case Bytecodes::_dup_x2:
   535         { ArgumentMap w1 = state.raw_pop();
   536           ArgumentMap w2 = state.raw_pop();
   537           ArgumentMap w3 = state.raw_pop();
   538           state.raw_push(w1);
   539           state.raw_push(w3);
   540           state.raw_push(w2);
   541           state.raw_push(w1);
   542         }
   543         break;
   544       case Bytecodes::_dup2:
   545         { ArgumentMap w1 = state.raw_pop();
   546           ArgumentMap w2 = state.raw_pop();
   547           state.raw_push(w2);
   548           state.raw_push(w1);
   549           state.raw_push(w2);
   550           state.raw_push(w1);
   551         }
   552         break;
   553       case Bytecodes::_dup2_x1:
   554         { ArgumentMap w1 = state.raw_pop();
   555           ArgumentMap w2 = state.raw_pop();
   556           ArgumentMap w3 = state.raw_pop();
   557           state.raw_push(w2);
   558           state.raw_push(w1);
   559           state.raw_push(w3);
   560           state.raw_push(w2);
   561           state.raw_push(w1);
   562         }
   563         break;
   564       case Bytecodes::_dup2_x2:
   565         { ArgumentMap w1 = state.raw_pop();
   566           ArgumentMap w2 = state.raw_pop();
   567           ArgumentMap w3 = state.raw_pop();
   568           ArgumentMap w4 = state.raw_pop();
   569           state.raw_push(w2);
   570           state.raw_push(w1);
   571           state.raw_push(w4);
   572           state.raw_push(w3);
   573           state.raw_push(w2);
   574           state.raw_push(w1);
   575         }
   576         break;
   577       case Bytecodes::_swap:
   578         { ArgumentMap w1 = state.raw_pop();
   579           ArgumentMap w2 = state.raw_pop();
   580           state.raw_push(w1);
   581           state.raw_push(w2);
   582         }
   583         break;
   584       case Bytecodes::_iadd:
   585       case Bytecodes::_fadd:
   586       case Bytecodes::_isub:
   587       case Bytecodes::_fsub:
   588       case Bytecodes::_imul:
   589       case Bytecodes::_fmul:
   590       case Bytecodes::_idiv:
   591       case Bytecodes::_fdiv:
   592       case Bytecodes::_irem:
   593       case Bytecodes::_frem:
   594       case Bytecodes::_iand:
   595       case Bytecodes::_ior:
   596       case Bytecodes::_ixor:
   597         state.spop();
   598         state.spop();
   599         state.spush();
   600         break;
   601       case Bytecodes::_ladd:
   602       case Bytecodes::_dadd:
   603       case Bytecodes::_lsub:
   604       case Bytecodes::_dsub:
   605       case Bytecodes::_lmul:
   606       case Bytecodes::_dmul:
   607       case Bytecodes::_ldiv:
   608       case Bytecodes::_ddiv:
   609       case Bytecodes::_lrem:
   610       case Bytecodes::_drem:
   611       case Bytecodes::_land:
   612       case Bytecodes::_lor:
   613       case Bytecodes::_lxor:
   614         state.lpop();
   615         state.lpop();
   616         state.lpush();
   617         break;
   618       case Bytecodes::_ishl:
   619       case Bytecodes::_ishr:
   620       case Bytecodes::_iushr:
   621         state.spop();
   622         state.spop();
   623         state.spush();
   624         break;
   625       case Bytecodes::_lshl:
   626       case Bytecodes::_lshr:
   627       case Bytecodes::_lushr:
   628         state.spop();
   629         state.lpop();
   630         state.lpush();
   631         break;
   632       case Bytecodes::_ineg:
   633       case Bytecodes::_fneg:
   634         state.spop();
   635         state.spush();
   636         break;
   637       case Bytecodes::_lneg:
   638       case Bytecodes::_dneg:
   639         state.lpop();
   640         state.lpush();
   641         break;
   642       case Bytecodes::_iinc:
   643         break;
   644       case Bytecodes::_i2l:
   645       case Bytecodes::_i2d:
   646       case Bytecodes::_f2l:
   647       case Bytecodes::_f2d:
   648         state.spop();
   649         state.lpush();
   650         break;
   651       case Bytecodes::_i2f:
   652       case Bytecodes::_f2i:
   653         state.spop();
   654         state.spush();
   655         break;
   656       case Bytecodes::_l2i:
   657       case Bytecodes::_l2f:
   658       case Bytecodes::_d2i:
   659       case Bytecodes::_d2f:
   660         state.lpop();
   661         state.spush();
   662         break;
   663       case Bytecodes::_l2d:
   664       case Bytecodes::_d2l:
   665         state.lpop();
   666         state.lpush();
   667         break;
   668       case Bytecodes::_i2b:
   669       case Bytecodes::_i2c:
   670       case Bytecodes::_i2s:
   671         state.spop();
   672         state.spush();
   673         break;
   674       case Bytecodes::_lcmp:
   675       case Bytecodes::_dcmpl:
   676       case Bytecodes::_dcmpg:
   677         state.lpop();
   678         state.lpop();
   679         state.spush();
   680         break;
   681       case Bytecodes::_fcmpl:
   682       case Bytecodes::_fcmpg:
   683         state.spop();
   684         state.spop();
   685         state.spush();
   686         break;
   687       case Bytecodes::_ifeq:
   688       case Bytecodes::_ifne:
   689       case Bytecodes::_iflt:
   690       case Bytecodes::_ifge:
   691       case Bytecodes::_ifgt:
   692       case Bytecodes::_ifle:
   693       {
   694         state.spop();
   695         int dest_bci = s.get_dest();
   696         assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
   697         assert(s.next_bci() == limit_bci, "branch must end block");
   698         successors.push(_methodBlocks->block_containing(dest_bci));
   699         break;
   700       }
   701       case Bytecodes::_if_icmpeq:
   702       case Bytecodes::_if_icmpne:
   703       case Bytecodes::_if_icmplt:
   704       case Bytecodes::_if_icmpge:
   705       case Bytecodes::_if_icmpgt:
   706       case Bytecodes::_if_icmple:
   707       {
   708         state.spop();
   709         state.spop();
   710         int dest_bci = s.get_dest();
   711         assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
   712         assert(s.next_bci() == limit_bci, "branch must end block");
   713         successors.push(_methodBlocks->block_containing(dest_bci));
   714         break;
   715       }
   716       case Bytecodes::_if_acmpeq:
   717       case Bytecodes::_if_acmpne:
   718       {
   719         set_method_escape(state.apop());
   720         set_method_escape(state.apop());
   721         int dest_bci = s.get_dest();
   722         assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
   723         assert(s.next_bci() == limit_bci, "branch must end block");
   724         successors.push(_methodBlocks->block_containing(dest_bci));
   725         break;
   726       }
   727       case Bytecodes::_goto:
   728       {
   729         int dest_bci = s.get_dest();
   730         assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
   731         assert(s.next_bci() == limit_bci, "branch must end block");
   732         successors.push(_methodBlocks->block_containing(dest_bci));
   733         fall_through = false;
   734         break;
   735       }
   736       case Bytecodes::_jsr:
   737       {
   738         int dest_bci = s.get_dest();
   739         assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
   740         assert(s.next_bci() == limit_bci, "branch must end block");
   741         state.apush(empty_map);
   742         successors.push(_methodBlocks->block_containing(dest_bci));
   743         fall_through = false;
   744         break;
   745       }
   746       case Bytecodes::_ret:
   747         // we don't track  the destination of a "ret" instruction
   748         assert(s.next_bci() == limit_bci, "branch must end block");
   749         fall_through = false;
   750         break;
   751       case Bytecodes::_return:
   752         assert(s.next_bci() == limit_bci, "return must end block");
   753         fall_through = false;
   754         break;
   755       case Bytecodes::_tableswitch:
   756         {
   757           state.spop();
   758           Bytecode_tableswitch* switch_ = Bytecode_tableswitch_at(s.cur_bcp());
   759           int len = switch_->length();
   760           int dest_bci;
   761           for (int i = 0; i < len; i++) {
   762             dest_bci = s.cur_bci() + switch_->dest_offset_at(i);
   763             assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
   764             successors.push(_methodBlocks->block_containing(dest_bci));
   765           }
   766           dest_bci = s.cur_bci() + switch_->default_offset();
   767           assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
   768           successors.push(_methodBlocks->block_containing(dest_bci));
   769           assert(s.next_bci() == limit_bci, "branch must end block");
   770           fall_through = false;
   771           break;
   772         }
   773       case Bytecodes::_lookupswitch:
   774         {
   775           state.spop();
   776           Bytecode_lookupswitch* switch_ = Bytecode_lookupswitch_at(s.cur_bcp());
   777           int len = switch_->number_of_pairs();
   778           int dest_bci;
   779           for (int i = 0; i < len; i++) {
   780             dest_bci = s.cur_bci() + switch_->pair_at(i)->offset();
   781             assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
   782             successors.push(_methodBlocks->block_containing(dest_bci));
   783           }
   784           dest_bci = s.cur_bci() + switch_->default_offset();
   785           assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
   786           successors.push(_methodBlocks->block_containing(dest_bci));
   787           fall_through = false;
   788           break;
   789         }
   790       case Bytecodes::_ireturn:
   791       case Bytecodes::_freturn:
   792         state.spop();
   793         fall_through = false;
   794         break;
   795       case Bytecodes::_lreturn:
   796       case Bytecodes::_dreturn:
   797         state.lpop();
   798         fall_through = false;
   799         break;
   800       case Bytecodes::_areturn:
   801         set_returned(state.apop());
   802         fall_through = false;
   803         break;
   804       case Bytecodes::_getstatic:
   805       case Bytecodes::_getfield:
   806         { bool will_link;
   807           ciField* field = s.get_field(will_link);
   808           BasicType field_type = field->type()->basic_type();
   809           if (s.cur_bc() != Bytecodes::_getstatic) {
   810             set_method_escape(state.apop());
   811           }
   812           if (field_type == T_OBJECT || field_type == T_ARRAY) {
   813             state.apush(unknown_obj);
   814           } else if (type2size[field_type] == 1) {
   815             state.spush();
   816           } else {
   817             state.lpush();
   818           }
   819         }
   820         break;
   821       case Bytecodes::_putstatic:
   822       case Bytecodes::_putfield:
   823         { bool will_link;
   824           ciField* field = s.get_field(will_link);
   825           BasicType field_type = field->type()->basic_type();
   826           if (field_type == T_OBJECT || field_type == T_ARRAY) {
   827             set_global_escape(state.apop());
   828           } else if (type2size[field_type] == 1) {
   829             state.spop();
   830           } else {
   831             state.lpop();
   832           }
   833           if (s.cur_bc() != Bytecodes::_putstatic) {
   834             ArgumentMap p = state.apop();
   835             set_method_escape(p);
   836             set_modified(p, will_link ? field->offset() : OFFSET_ANY, type2size[field_type]*HeapWordSize);
   837           }
   838         }
   839         break;
   840       case Bytecodes::_invokevirtual:
   841       case Bytecodes::_invokespecial:
   842       case Bytecodes::_invokestatic:
   843       case Bytecodes::_invokedynamic:
   844       case Bytecodes::_invokeinterface:
   845         { bool will_link;
   846           ciMethod* target = s.get_method(will_link);
   847           ciKlass* holder = s.get_declared_method_holder();
   848           invoke(state, s.cur_bc(), target, holder);
   849           ciType* return_type = target->return_type();
   850           if (!return_type->is_primitive_type()) {
   851             state.apush(unknown_obj);
   852           } else if (return_type->is_one_word()) {
   853             state.spush();
   854           } else if (return_type->is_two_word()) {
   855             state.lpush();
   856           }
   857         }
   858         break;
   859       case Bytecodes::_new:
   860         state.apush(allocated_obj);
   861         break;
   862       case Bytecodes::_newarray:
   863       case Bytecodes::_anewarray:
   864         state.spop();
   865         state.apush(allocated_obj);
   866         break;
   867       case Bytecodes::_multianewarray:
   868         { int i = s.cur_bcp()[3];
   869           while (i-- > 0) state.spop();
   870           state.apush(allocated_obj);
   871         }
   872         break;
   873       case Bytecodes::_arraylength:
   874         set_method_escape(state.apop());
   875         state.spush();
   876         break;
   877       case Bytecodes::_athrow:
   878         set_global_escape(state.apop());
   879         fall_through = false;
   880         break;
   881       case Bytecodes::_checkcast:
   882         { ArgumentMap obj = state.apop();
   883           set_method_escape(obj);
   884           state.apush(obj);
   885         }
   886         break;
   887       case Bytecodes::_instanceof:
   888         set_method_escape(state.apop());
   889         state.spush();
   890         break;
   891       case Bytecodes::_monitorenter:
   892       case Bytecodes::_monitorexit:
   893         state.apop();
   894         break;
   895       case Bytecodes::_wide:
   896         ShouldNotReachHere();
   897         break;
   898       case Bytecodes::_ifnull:
   899       case Bytecodes::_ifnonnull:
   900       {
   901         set_method_escape(state.apop());
   902         int dest_bci = s.get_dest();
   903         assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
   904         assert(s.next_bci() == limit_bci, "branch must end block");
   905         successors.push(_methodBlocks->block_containing(dest_bci));
   906         break;
   907       }
   908       case Bytecodes::_goto_w:
   909       {
   910         int dest_bci = s.get_far_dest();
   911         assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
   912         assert(s.next_bci() == limit_bci, "branch must end block");
   913         successors.push(_methodBlocks->block_containing(dest_bci));
   914         fall_through = false;
   915         break;
   916       }
   917       case Bytecodes::_jsr_w:
   918       {
   919         int dest_bci = s.get_far_dest();
   920         assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
   921         assert(s.next_bci() == limit_bci, "branch must end block");
   922         state.apush(empty_map);
   923         successors.push(_methodBlocks->block_containing(dest_bci));
   924         fall_through = false;
   925         break;
   926       }
   927       case Bytecodes::_breakpoint:
   928         break;
   929       default:
   930         ShouldNotReachHere();
   931         break;
   932     }
   934   }
   935   if (fall_through) {
   936     int fall_through_bci = s.cur_bci();
   937     if (fall_through_bci < _method->code_size()) {
   938       assert(_methodBlocks->is_block_start(fall_through_bci), "must fall through to block start.");
   939       successors.push(_methodBlocks->block_containing(fall_through_bci));
   940     }
   941   }
   942 }
   944 void BCEscapeAnalyzer::merge_block_states(StateInfo *blockstates, ciBlock *dest, StateInfo *s_state) {
   945   StateInfo *d_state = blockstates + dest->index();
   946   int nlocals = _method->max_locals();
   948   // exceptions may cause transfer of control to handlers in the middle of a
   949   // block, so we don't merge the incoming state of exception handlers
   950   if (dest->is_handler())
   951     return;
   952   if (!d_state->_initialized ) {
   953     // destination not initialized, just copy
   954     for (int i = 0; i < nlocals; i++) {
   955       d_state->_vars[i] = s_state->_vars[i];
   956     }
   957     for (int i = 0; i < s_state->_stack_height; i++) {
   958       d_state->_stack[i] = s_state->_stack[i];
   959     }
   960     d_state->_stack_height = s_state->_stack_height;
   961     d_state->_max_stack = s_state->_max_stack;
   962     d_state->_initialized = true;
   963   } else if (!dest->processed()) {
   964     // we have not yet walked the bytecodes of dest, we can merge
   965     // the states
   966     assert(d_state->_stack_height == s_state->_stack_height, "computed stack heights must match");
   967     for (int i = 0; i < nlocals; i++) {
   968       d_state->_vars[i].set_union(s_state->_vars[i]);
   969     }
   970     for (int i = 0; i < s_state->_stack_height; i++) {
   971       d_state->_stack[i].set_union(s_state->_stack[i]);
   972     }
   973   } else {
   974     // the bytecodes of dest have already been processed, mark any
   975     // arguments in the source state which are not in the dest state
   976     // as global escape.
   977     // Future refinement:  we only need to mark these variable to the
   978     // maximum escape of any variables in dest state
   979     assert(d_state->_stack_height == s_state->_stack_height, "computed stack heights must match");
   980     ArgumentMap extra_vars;
   981     for (int i = 0; i < nlocals; i++) {
   982       ArgumentMap t;
   983       t = s_state->_vars[i];
   984       t.set_difference(d_state->_vars[i]);
   985       extra_vars.set_union(t);
   986     }
   987     for (int i = 0; i < s_state->_stack_height; i++) {
   988       ArgumentMap t;
   989       //extra_vars |= !d_state->_vars[i] & s_state->_vars[i];
   990       t.clear();
   991       t = s_state->_stack[i];
   992       t.set_difference(d_state->_stack[i]);
   993       extra_vars.set_union(t);
   994     }
   995     set_global_escape(extra_vars);
   996   }
   997 }
   999 void BCEscapeAnalyzer::iterate_blocks(Arena *arena) {
  1000   int numblocks = _methodBlocks->num_blocks();
  1001   int stkSize   = _method->max_stack();
  1002   int numLocals = _method->max_locals();
  1003   StateInfo state;
  1005   int datacount = (numblocks + 1) * (stkSize + numLocals);
  1006   int datasize = datacount * sizeof(ArgumentMap);
  1007   StateInfo *blockstates = (StateInfo *) arena->Amalloc(numblocks * sizeof(StateInfo));
  1008   ArgumentMap *statedata  = (ArgumentMap *) arena->Amalloc(datasize);
  1009   for (int i = 0; i < datacount; i++) ::new ((void*)&statedata[i]) ArgumentMap();
  1010   ArgumentMap *dp = statedata;
  1011   state._vars = dp;
  1012   dp += numLocals;
  1013   state._stack = dp;
  1014   dp += stkSize;
  1015   state._initialized = false;
  1016   state._max_stack = stkSize;
  1017   for (int i = 0; i < numblocks; i++) {
  1018     blockstates[i]._vars = dp;
  1019     dp += numLocals;
  1020     blockstates[i]._stack = dp;
  1021     dp += stkSize;
  1022     blockstates[i]._initialized = false;
  1023     blockstates[i]._stack_height = 0;
  1024     blockstates[i]._max_stack  = stkSize;
  1026   GrowableArray<ciBlock *> worklist(arena, numblocks / 4, 0, NULL);
  1027   GrowableArray<ciBlock *> successors(arena, 4, 0, NULL);
  1029   _methodBlocks->clear_processed();
  1031   // initialize block 0 state from method signature
  1032   ArgumentMap allVars;   // all oop arguments to method
  1033   ciSignature* sig = method()->signature();
  1034   int j = 0;
  1035   ciBlock* first_blk = _methodBlocks->block_containing(0);
  1036   int fb_i = first_blk->index();
  1037   if (!method()->is_static()) {
  1038     // record information for "this"
  1039     blockstates[fb_i]._vars[j].set(j);
  1040     allVars.add(j);
  1041     j++;
  1043   for (int i = 0; i < sig->count(); i++) {
  1044     ciType* t = sig->type_at(i);
  1045     if (!t->is_primitive_type()) {
  1046       blockstates[fb_i]._vars[j].set(j);
  1047       allVars.add(j);
  1049     j += t->size();
  1051   blockstates[fb_i]._initialized = true;
  1052   assert(j == _arg_size, "just checking");
  1054   ArgumentMap unknown_map;
  1055   unknown_map.add_unknown();
  1057   worklist.push(first_blk);
  1058   while(worklist.length() > 0) {
  1059     ciBlock *blk = worklist.pop();
  1060     StateInfo *blkState = blockstates + blk->index();
  1061     if (blk->is_handler() || blk->is_ret_target()) {
  1062       // for an exception handler or a target of a ret instruction, we assume the worst case,
  1063       // that any variable could contain any argument
  1064       for (int i = 0; i < numLocals; i++) {
  1065         state._vars[i] = allVars;
  1067       if (blk->is_handler()) {
  1068         state._stack_height = 1;
  1069       } else {
  1070         state._stack_height = blkState->_stack_height;
  1072       for (int i = 0; i < state._stack_height; i++) {
  1073 // ??? should this be unknown_map ???
  1074         state._stack[i] = allVars;
  1076     } else {
  1077       for (int i = 0; i < numLocals; i++) {
  1078         state._vars[i] = blkState->_vars[i];
  1080       for (int i = 0; i < blkState->_stack_height; i++) {
  1081         state._stack[i] = blkState->_stack[i];
  1083       state._stack_height = blkState->_stack_height;
  1085     iterate_one_block(blk, state, successors);
  1086     // if this block has any exception handlers, push them
  1087     // onto successor list
  1088     if (blk->has_handler()) {
  1089       DEBUG_ONLY(int handler_count = 0;)
  1090       int blk_start = blk->start_bci();
  1091       int blk_end = blk->limit_bci();
  1092       for (int i = 0; i < numblocks; i++) {
  1093         ciBlock *b = _methodBlocks->block(i);
  1094         if (b->is_handler()) {
  1095           int ex_start = b->ex_start_bci();
  1096           int ex_end = b->ex_limit_bci();
  1097           if ((ex_start >= blk_start && ex_start < blk_end) ||
  1098               (ex_end > blk_start && ex_end <= blk_end)) {
  1099             successors.push(b);
  1101           DEBUG_ONLY(handler_count++;)
  1104       assert(handler_count > 0, "must find at least one handler");
  1106     // merge computed variable state with successors
  1107     while(successors.length() > 0) {
  1108       ciBlock *succ = successors.pop();
  1109       merge_block_states(blockstates, succ, &state);
  1110       if (!succ->processed())
  1111         worklist.push(succ);
  1116 bool BCEscapeAnalyzer::do_analysis() {
  1117   Arena* arena = CURRENT_ENV->arena();
  1118   // identify basic blocks
  1119   _methodBlocks = _method->get_method_blocks();
  1121   iterate_blocks(arena);
  1122   // TEMPORARY
  1123   return true;
  1126 vmIntrinsics::ID BCEscapeAnalyzer::known_intrinsic() {
  1127   vmIntrinsics::ID iid = method()->intrinsic_id();
  1129   if (iid == vmIntrinsics::_getClass ||
  1130       iid ==  vmIntrinsics::_fillInStackTrace ||
  1131       iid == vmIntrinsics::_hashCode)
  1132     return iid;
  1133   else
  1134     return vmIntrinsics::_none;
  1137 bool BCEscapeAnalyzer::compute_escape_for_intrinsic(vmIntrinsics::ID iid) {
  1138   ArgumentMap arg;
  1139   arg.clear();
  1140   switch (iid) {
  1141   case vmIntrinsics::_getClass:
  1142     _return_local = false;
  1143     break;
  1144   case vmIntrinsics::_fillInStackTrace:
  1145     arg.set(0); // 'this'
  1146     set_returned(arg);
  1147     break;
  1148   case vmIntrinsics::_hashCode:
  1149     // initialized state is correct
  1150     break;
  1151   default:
  1152     assert(false, "unexpected intrinsic");
  1154   return true;
  1157 void BCEscapeAnalyzer::initialize() {
  1158   int i;
  1160   // clear escape information (method may have been deoptimized)
  1161   methodData()->clear_escape_info();
  1163   // initialize escape state of object parameters
  1164   ciSignature* sig = method()->signature();
  1165   int j = 0;
  1166   if (!method()->is_static()) {
  1167     _arg_local.set(0);
  1168     _arg_stack.set(0);
  1169     j++;
  1171   for (i = 0; i < sig->count(); i++) {
  1172     ciType* t = sig->type_at(i);
  1173     if (!t->is_primitive_type()) {
  1174       _arg_local.set(j);
  1175       _arg_stack.set(j);
  1177     j += t->size();
  1179   assert(j == _arg_size, "just checking");
  1181   // start with optimistic assumption
  1182   ciType *rt = _method->return_type();
  1183   if (rt->is_primitive_type()) {
  1184     _return_local = false;
  1185     _return_allocated = false;
  1186   } else {
  1187     _return_local = true;
  1188     _return_allocated = true;
  1190   _allocated_escapes = false;
  1191   _unknown_modified = false;
  1194 void BCEscapeAnalyzer::clear_escape_info() {
  1195   ciSignature* sig = method()->signature();
  1196   int arg_count = sig->count();
  1197   ArgumentMap var;
  1198   if (!method()->is_static()) {
  1199     arg_count++;  // allow for "this"
  1201   for (int i = 0; i < arg_count; i++) {
  1202     set_arg_modified(i, OFFSET_ANY, 4);
  1203     var.clear();
  1204     var.set(i);
  1205     set_modified(var, OFFSET_ANY, 4);
  1206     set_global_escape(var);
  1208   _arg_local.Clear();
  1209   _arg_stack.Clear();
  1210   _arg_returned.Clear();
  1211   _return_local = false;
  1212   _return_allocated = false;
  1213   _allocated_escapes = true;
  1214   _unknown_modified = true;
  1218 void BCEscapeAnalyzer::compute_escape_info() {
  1219   int i;
  1220   assert(!methodData()->has_escape_info(), "do not overwrite escape info");
  1222   vmIntrinsics::ID iid = known_intrinsic();
  1224   // check if method can be analyzed
  1225   if (iid ==  vmIntrinsics::_none && (method()->is_abstract() || method()->is_native() || !method()->holder()->is_initialized()
  1226       || _level > MaxBCEAEstimateLevel
  1227       || method()->code_size() > MaxBCEAEstimateSize)) {
  1228     if (BCEATraceLevel >= 1) {
  1229       tty->print("Skipping method because: ");
  1230       if (method()->is_abstract())
  1231         tty->print_cr("method is abstract.");
  1232       else if (method()->is_native())
  1233         tty->print_cr("method is native.");
  1234       else if (!method()->holder()->is_initialized())
  1235         tty->print_cr("class of method is not initialized.");
  1236       else if (_level > MaxBCEAEstimateLevel)
  1237         tty->print_cr("level (%d) exceeds MaxBCEAEstimateLevel (%d).",
  1238                       _level, MaxBCEAEstimateLevel);
  1239       else if (method()->code_size() > MaxBCEAEstimateSize)
  1240         tty->print_cr("code size (%d) exceeds MaxBCEAEstimateSize.",
  1241                       method()->code_size(), MaxBCEAEstimateSize);
  1242       else
  1243         ShouldNotReachHere();
  1245     clear_escape_info();
  1247     return;
  1250   if (BCEATraceLevel >= 1) {
  1251     tty->print("[EA] estimating escape information for");
  1252     if (iid != vmIntrinsics::_none)
  1253       tty->print(" intrinsic");
  1254     method()->print_short_name();
  1255     tty->print_cr(" (%d bytes)", method()->code_size());
  1258   bool success;
  1260   initialize();
  1262   // Do not scan method if it has no object parameters and
  1263   // does not returns an object (_return_allocated is set in initialize()).
  1264   if (_arg_local.Size() == 0 && !_return_allocated) {
  1265     // Clear all info since method's bytecode was not analysed and
  1266     // set pessimistic escape information.
  1267     clear_escape_info();
  1268     methodData()->set_eflag(methodDataOopDesc::allocated_escapes);
  1269     methodData()->set_eflag(methodDataOopDesc::unknown_modified);
  1270     methodData()->set_eflag(methodDataOopDesc::estimated);
  1271     return;
  1274   if (iid != vmIntrinsics::_none)
  1275     success = compute_escape_for_intrinsic(iid);
  1276   else {
  1277     success = do_analysis();
  1280   // don't store interprocedural escape information if it introduces
  1281   // dependencies or if method data is empty
  1282   //
  1283   if (!has_dependencies() && !methodData()->is_empty()) {
  1284     for (i = 0; i < _arg_size; i++) {
  1285       if (_arg_local.test(i)) {
  1286         assert(_arg_stack.test(i), "inconsistent escape info");
  1287         methodData()->set_arg_local(i);
  1288         methodData()->set_arg_stack(i);
  1289       } else if (_arg_stack.test(i)) {
  1290         methodData()->set_arg_stack(i);
  1292       if (_arg_returned.test(i)) {
  1293         methodData()->set_arg_returned(i);
  1295       methodData()->set_arg_modified(i, _arg_modified[i]);
  1297     if (_return_local) {
  1298       methodData()->set_eflag(methodDataOopDesc::return_local);
  1300     if (_return_allocated) {
  1301       methodData()->set_eflag(methodDataOopDesc::return_allocated);
  1303     if (_allocated_escapes) {
  1304       methodData()->set_eflag(methodDataOopDesc::allocated_escapes);
  1306     if (_unknown_modified) {
  1307       methodData()->set_eflag(methodDataOopDesc::unknown_modified);
  1309     methodData()->set_eflag(methodDataOopDesc::estimated);
  1313 void BCEscapeAnalyzer::read_escape_info() {
  1314   assert(methodData()->has_escape_info(), "no escape info available");
  1316   // read escape information from method descriptor
  1317   for (int i = 0; i < _arg_size; i++) {
  1318     if (methodData()->is_arg_local(i))
  1319       _arg_local.set(i);
  1320     if (methodData()->is_arg_stack(i))
  1321       _arg_stack.set(i);
  1322     if (methodData()->is_arg_returned(i))
  1323       _arg_returned.set(i);
  1324     _arg_modified[i] = methodData()->arg_modified(i);
  1326   _return_local = methodData()->eflag_set(methodDataOopDesc::return_local);
  1327   _return_allocated = methodData()->eflag_set(methodDataOopDesc::return_allocated);
  1328   _allocated_escapes = methodData()->eflag_set(methodDataOopDesc::allocated_escapes);
  1329   _unknown_modified = methodData()->eflag_set(methodDataOopDesc::unknown_modified);
  1333 #ifndef PRODUCT
  1334 void BCEscapeAnalyzer::dump() {
  1335   tty->print("[EA] estimated escape information for");
  1336   method()->print_short_name();
  1337   tty->print_cr(has_dependencies() ? " (not stored)" : "");
  1338   tty->print("     non-escaping args:      ");
  1339   _arg_local.print_on(tty);
  1340   tty->print("     stack-allocatable args: ");
  1341   _arg_stack.print_on(tty);
  1342   if (_return_local) {
  1343     tty->print("     returned args:          ");
  1344     _arg_returned.print_on(tty);
  1345   } else if (is_return_allocated()) {
  1346     tty->print_cr("     return allocated value");
  1347   } else {
  1348     tty->print_cr("     return non-local value");
  1350   tty->print("     modified args: ");
  1351   for (int i = 0; i < _arg_size; i++) {
  1352     if (_arg_modified[i] == 0)
  1353       tty->print("    0");
  1354     else
  1355       tty->print("    0x%x", _arg_modified[i]);
  1357   tty->cr();
  1358   tty->print("     flags: ");
  1359   if (_return_allocated)
  1360     tty->print(" return_allocated");
  1361   if (_allocated_escapes)
  1362     tty->print(" allocated_escapes");
  1363   if (_unknown_modified)
  1364     tty->print(" unknown_modified");
  1365   tty->cr();
  1367 #endif
  1369 BCEscapeAnalyzer::BCEscapeAnalyzer(ciMethod* method, BCEscapeAnalyzer* parent)
  1370     : _conservative(method == NULL || !EstimateArgEscape)
  1371     , _arena(CURRENT_ENV->arena())
  1372     , _method(method)
  1373     , _methodData(method ? method->method_data() : NULL)
  1374     , _arg_size(method ? method->arg_size() : 0)
  1375     , _arg_local(_arena)
  1376     , _arg_stack(_arena)
  1377     , _arg_returned(_arena)
  1378     , _dirty(_arena)
  1379     , _return_local(false)
  1380     , _return_allocated(false)
  1381     , _allocated_escapes(false)
  1382     , _unknown_modified(false)
  1383     , _dependencies(_arena, 4, 0, NULL)
  1384     , _parent(parent)
  1385     , _level(parent == NULL ? 0 : parent->level() + 1) {
  1386   if (!_conservative) {
  1387     _arg_local.Clear();
  1388     _arg_stack.Clear();
  1389     _arg_returned.Clear();
  1390     _dirty.Clear();
  1391     Arena* arena = CURRENT_ENV->arena();
  1392     _arg_modified = (uint *) arena->Amalloc(_arg_size * sizeof(uint));
  1393     Copy::zero_to_bytes(_arg_modified, _arg_size * sizeof(uint));
  1395     if (methodData() == NULL)
  1396       return;
  1397     bool printit = _method->should_print_assembly();
  1398     if (methodData()->has_escape_info()) {
  1399       TRACE_BCEA(2, tty->print_cr("[EA] Reading previous results for %s.%s",
  1400                                   method->holder()->name()->as_utf8(),
  1401                                   method->name()->as_utf8()));
  1402       read_escape_info();
  1403     } else {
  1404       TRACE_BCEA(2, tty->print_cr("[EA] computing results for %s.%s",
  1405                                   method->holder()->name()->as_utf8(),
  1406                                   method->name()->as_utf8()));
  1408       compute_escape_info();
  1409       methodData()->update_escape_info();
  1411 #ifndef PRODUCT
  1412     if (BCEATraceLevel >= 3) {
  1413       // dump escape information
  1414       dump();
  1416 #endif
  1420 void BCEscapeAnalyzer::copy_dependencies(Dependencies *deps) {
  1421   if (ciEnv::current()->jvmti_can_hotswap_or_post_breakpoint()) {
  1422     // Also record evol dependencies so redefinition of the
  1423     // callee will trigger recompilation.
  1424     deps->assert_evol_method(method());
  1426   for (int i = 0; i < _dependencies.length(); i+=2) {
  1427     ciKlass *k = _dependencies.at(i)->as_klass();
  1428     ciMethod *m = _dependencies.at(i+1)->as_method();
  1429     deps->assert_unique_concrete_method(k, m);

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