src/share/vm/ci/ciTypeFlow.cpp

Tue, 25 Nov 2014 15:59:42 +0100

author
goetz
date
Tue, 25 Nov 2014 15:59:42 +0100
changeset 7546
4181e5e64dd0
parent 7385
9e69e8d1c900
child 7994
04ff2f6cd0eb
permissions
-rw-r--r--

8065915: Fix includes after 8058148: MaxNodeLimit and LiveNodeCountInliningCutoff
Reviewed-by: vlivanov, dholmes

     1 /*
     2  * Copyright (c) 2000, 2013, 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  */
    25 #include "precompiled.hpp"
    26 #include "ci/ciConstant.hpp"
    27 #include "ci/ciField.hpp"
    28 #include "ci/ciMethod.hpp"
    29 #include "ci/ciMethodData.hpp"
    30 #include "ci/ciObjArrayKlass.hpp"
    31 #include "ci/ciStreams.hpp"
    32 #include "ci/ciTypeArrayKlass.hpp"
    33 #include "ci/ciTypeFlow.hpp"
    34 #include "compiler/compileLog.hpp"
    35 #include "interpreter/bytecode.hpp"
    36 #include "interpreter/bytecodes.hpp"
    37 #include "memory/allocation.inline.hpp"
    38 #include "opto/compile.hpp"
    39 #include "opto/node.hpp"
    40 #include "runtime/deoptimization.hpp"
    41 #include "utilities/growableArray.hpp"
    43 // ciTypeFlow::JsrSet
    44 //
    45 // A JsrSet represents some set of JsrRecords.  This class
    46 // is used to record a set of all jsr routines which we permit
    47 // execution to return (ret) from.
    48 //
    49 // During abstract interpretation, JsrSets are used to determine
    50 // whether two paths which reach a given block are unique, and
    51 // should be cloned apart, or are compatible, and should merge
    52 // together.
    54 // ------------------------------------------------------------------
    55 // ciTypeFlow::JsrSet::JsrSet
    56 ciTypeFlow::JsrSet::JsrSet(Arena* arena, int default_len) {
    57   if (arena != NULL) {
    58     // Allocate growable array in Arena.
    59     _set = new (arena) GrowableArray<JsrRecord*>(arena, default_len, 0, NULL);
    60   } else {
    61     // Allocate growable array in current ResourceArea.
    62     _set = new GrowableArray<JsrRecord*>(4, 0, NULL, false);
    63   }
    64 }
    66 // ------------------------------------------------------------------
    67 // ciTypeFlow::JsrSet::copy_into
    68 void ciTypeFlow::JsrSet::copy_into(JsrSet* jsrs) {
    69   int len = size();
    70   jsrs->_set->clear();
    71   for (int i = 0; i < len; i++) {
    72     jsrs->_set->append(_set->at(i));
    73   }
    74 }
    76 // ------------------------------------------------------------------
    77 // ciTypeFlow::JsrSet::is_compatible_with
    78 //
    79 // !!!! MISGIVINGS ABOUT THIS... disregard
    80 //
    81 // Is this JsrSet compatible with some other JsrSet?
    82 //
    83 // In set-theoretic terms, a JsrSet can be viewed as a partial function
    84 // from entry addresses to return addresses.  Two JsrSets A and B are
    85 // compatible iff
    86 //
    87 //   For any x,
    88 //   A(x) defined and B(x) defined implies A(x) == B(x)
    89 //
    90 // Less formally, two JsrSets are compatible when they have identical
    91 // return addresses for any entry addresses they share in common.
    92 bool ciTypeFlow::JsrSet::is_compatible_with(JsrSet* other) {
    93   // Walk through both sets in parallel.  If the same entry address
    94   // appears in both sets, then the return address must match for
    95   // the sets to be compatible.
    96   int size1 = size();
    97   int size2 = other->size();
    99   // Special case.  If nothing is on the jsr stack, then there can
   100   // be no ret.
   101   if (size2 == 0) {
   102     return true;
   103   } else if (size1 != size2) {
   104     return false;
   105   } else {
   106     for (int i = 0; i < size1; i++) {
   107       JsrRecord* record1 = record_at(i);
   108       JsrRecord* record2 = other->record_at(i);
   109       if (record1->entry_address() != record2->entry_address() ||
   110           record1->return_address() != record2->return_address()) {
   111         return false;
   112       }
   113     }
   114     return true;
   115   }
   117 #if 0
   118   int pos1 = 0;
   119   int pos2 = 0;
   120   int size1 = size();
   121   int size2 = other->size();
   122   while (pos1 < size1 && pos2 < size2) {
   123     JsrRecord* record1 = record_at(pos1);
   124     JsrRecord* record2 = other->record_at(pos2);
   125     int entry1 = record1->entry_address();
   126     int entry2 = record2->entry_address();
   127     if (entry1 < entry2) {
   128       pos1++;
   129     } else if (entry1 > entry2) {
   130       pos2++;
   131     } else {
   132       if (record1->return_address() == record2->return_address()) {
   133         pos1++;
   134         pos2++;
   135       } else {
   136         // These two JsrSets are incompatible.
   137         return false;
   138       }
   139     }
   140   }
   141   // The two JsrSets agree.
   142   return true;
   143 #endif
   144 }
   146 // ------------------------------------------------------------------
   147 // ciTypeFlow::JsrSet::insert_jsr_record
   148 //
   149 // Insert the given JsrRecord into the JsrSet, maintaining the order
   150 // of the set and replacing any element with the same entry address.
   151 void ciTypeFlow::JsrSet::insert_jsr_record(JsrRecord* record) {
   152   int len = size();
   153   int entry = record->entry_address();
   154   int pos = 0;
   155   for ( ; pos < len; pos++) {
   156     JsrRecord* current = record_at(pos);
   157     if (entry == current->entry_address()) {
   158       // Stomp over this entry.
   159       _set->at_put(pos, record);
   160       assert(size() == len, "must be same size");
   161       return;
   162     } else if (entry < current->entry_address()) {
   163       break;
   164     }
   165   }
   167   // Insert the record into the list.
   168   JsrRecord* swap = record;
   169   JsrRecord* temp = NULL;
   170   for ( ; pos < len; pos++) {
   171     temp = _set->at(pos);
   172     _set->at_put(pos, swap);
   173     swap = temp;
   174   }
   175   _set->append(swap);
   176   assert(size() == len+1, "must be larger");
   177 }
   179 // ------------------------------------------------------------------
   180 // ciTypeFlow::JsrSet::remove_jsr_record
   181 //
   182 // Remove the JsrRecord with the given return address from the JsrSet.
   183 void ciTypeFlow::JsrSet::remove_jsr_record(int return_address) {
   184   int len = size();
   185   for (int i = 0; i < len; i++) {
   186     if (record_at(i)->return_address() == return_address) {
   187       // We have found the proper entry.  Remove it from the
   188       // JsrSet and exit.
   189       for (int j = i+1; j < len ; j++) {
   190         _set->at_put(j-1, _set->at(j));
   191       }
   192       _set->trunc_to(len-1);
   193       assert(size() == len-1, "must be smaller");
   194       return;
   195     }
   196   }
   197   assert(false, "verify: returning from invalid subroutine");
   198 }
   200 // ------------------------------------------------------------------
   201 // ciTypeFlow::JsrSet::apply_control
   202 //
   203 // Apply the effect of a control-flow bytecode on the JsrSet.  The
   204 // only bytecodes that modify the JsrSet are jsr and ret.
   205 void ciTypeFlow::JsrSet::apply_control(ciTypeFlow* analyzer,
   206                                        ciBytecodeStream* str,
   207                                        ciTypeFlow::StateVector* state) {
   208   Bytecodes::Code code = str->cur_bc();
   209   if (code == Bytecodes::_jsr) {
   210     JsrRecord* record =
   211       analyzer->make_jsr_record(str->get_dest(), str->next_bci());
   212     insert_jsr_record(record);
   213   } else if (code == Bytecodes::_jsr_w) {
   214     JsrRecord* record =
   215       analyzer->make_jsr_record(str->get_far_dest(), str->next_bci());
   216     insert_jsr_record(record);
   217   } else if (code == Bytecodes::_ret) {
   218     Cell local = state->local(str->get_index());
   219     ciType* return_address = state->type_at(local);
   220     assert(return_address->is_return_address(), "verify: wrong type");
   221     if (size() == 0) {
   222       // Ret-state underflow:  Hit a ret w/o any previous jsrs.  Bail out.
   223       // This can happen when a loop is inside a finally clause (4614060).
   224       analyzer->record_failure("OSR in finally clause");
   225       return;
   226     }
   227     remove_jsr_record(return_address->as_return_address()->bci());
   228   }
   229 }
   231 #ifndef PRODUCT
   232 // ------------------------------------------------------------------
   233 // ciTypeFlow::JsrSet::print_on
   234 void ciTypeFlow::JsrSet::print_on(outputStream* st) const {
   235   st->print("{ ");
   236   int num_elements = size();
   237   if (num_elements > 0) {
   238     int i = 0;
   239     for( ; i < num_elements - 1; i++) {
   240       _set->at(i)->print_on(st);
   241       st->print(", ");
   242     }
   243     _set->at(i)->print_on(st);
   244     st->print(" ");
   245   }
   246   st->print("}");
   247 }
   248 #endif
   250 // ciTypeFlow::StateVector
   251 //
   252 // A StateVector summarizes the type information at some point in
   253 // the program.
   255 // ------------------------------------------------------------------
   256 // ciTypeFlow::StateVector::type_meet
   257 //
   258 // Meet two types.
   259 //
   260 // The semi-lattice of types use by this analysis are modeled on those
   261 // of the verifier.  The lattice is as follows:
   262 //
   263 //        top_type() >= all non-extremal types >= bottom_type
   264 //                             and
   265 //   Every primitive type is comparable only with itself.  The meet of
   266 //   reference types is determined by their kind: instance class,
   267 //   interface, or array class.  The meet of two types of the same
   268 //   kind is their least common ancestor.  The meet of two types of
   269 //   different kinds is always java.lang.Object.
   270 ciType* ciTypeFlow::StateVector::type_meet_internal(ciType* t1, ciType* t2, ciTypeFlow* analyzer) {
   271   assert(t1 != t2, "checked in caller");
   272   if (t1->equals(top_type())) {
   273     return t2;
   274   } else if (t2->equals(top_type())) {
   275     return t1;
   276   } else if (t1->is_primitive_type() || t2->is_primitive_type()) {
   277     // Special case null_type.  null_type meet any reference type T
   278     // is T.  null_type meet null_type is null_type.
   279     if (t1->equals(null_type())) {
   280       if (!t2->is_primitive_type() || t2->equals(null_type())) {
   281         return t2;
   282       }
   283     } else if (t2->equals(null_type())) {
   284       if (!t1->is_primitive_type()) {
   285         return t1;
   286       }
   287     }
   289     // At least one of the two types is a non-top primitive type.
   290     // The other type is not equal to it.  Fall to bottom.
   291     return bottom_type();
   292   } else {
   293     // Both types are non-top non-primitive types.  That is,
   294     // both types are either instanceKlasses or arrayKlasses.
   295     ciKlass* object_klass = analyzer->env()->Object_klass();
   296     ciKlass* k1 = t1->as_klass();
   297     ciKlass* k2 = t2->as_klass();
   298     if (k1->equals(object_klass) || k2->equals(object_klass)) {
   299       return object_klass;
   300     } else if (!k1->is_loaded() || !k2->is_loaded()) {
   301       // Unloaded classes fall to java.lang.Object at a merge.
   302       return object_klass;
   303     } else if (k1->is_interface() != k2->is_interface()) {
   304       // When an interface meets a non-interface, we get Object;
   305       // This is what the verifier does.
   306       return object_klass;
   307     } else if (k1->is_array_klass() || k2->is_array_klass()) {
   308       // When an array meets a non-array, we get Object.
   309       // When objArray meets typeArray, we also get Object.
   310       // And when typeArray meets different typeArray, we again get Object.
   311       // But when objArray meets objArray, we look carefully at element types.
   312       if (k1->is_obj_array_klass() && k2->is_obj_array_klass()) {
   313         // Meet the element types, then construct the corresponding array type.
   314         ciKlass* elem1 = k1->as_obj_array_klass()->element_klass();
   315         ciKlass* elem2 = k2->as_obj_array_klass()->element_klass();
   316         ciKlass* elem  = type_meet_internal(elem1, elem2, analyzer)->as_klass();
   317         // Do an easy shortcut if one type is a super of the other.
   318         if (elem == elem1) {
   319           assert(k1 == ciObjArrayKlass::make(elem), "shortcut is OK");
   320           return k1;
   321         } else if (elem == elem2) {
   322           assert(k2 == ciObjArrayKlass::make(elem), "shortcut is OK");
   323           return k2;
   324         } else {
   325           return ciObjArrayKlass::make(elem);
   326         }
   327       } else {
   328         return object_klass;
   329       }
   330     } else {
   331       // Must be two plain old instance klasses.
   332       assert(k1->is_instance_klass(), "previous cases handle non-instances");
   333       assert(k2->is_instance_klass(), "previous cases handle non-instances");
   334       return k1->least_common_ancestor(k2);
   335     }
   336   }
   337 }
   340 // ------------------------------------------------------------------
   341 // ciTypeFlow::StateVector::StateVector
   342 //
   343 // Build a new state vector
   344 ciTypeFlow::StateVector::StateVector(ciTypeFlow* analyzer) {
   345   _outer = analyzer;
   346   _stack_size = -1;
   347   _monitor_count = -1;
   348   // Allocate the _types array
   349   int max_cells = analyzer->max_cells();
   350   _types = (ciType**)analyzer->arena()->Amalloc(sizeof(ciType*) * max_cells);
   351   for (int i=0; i<max_cells; i++) {
   352     _types[i] = top_type();
   353   }
   354   _trap_bci = -1;
   355   _trap_index = 0;
   356   _def_locals.clear();
   357 }
   360 // ------------------------------------------------------------------
   361 // ciTypeFlow::get_start_state
   362 //
   363 // Set this vector to the method entry state.
   364 const ciTypeFlow::StateVector* ciTypeFlow::get_start_state() {
   365   StateVector* state = new StateVector(this);
   366   if (is_osr_flow()) {
   367     ciTypeFlow* non_osr_flow = method()->get_flow_analysis();
   368     if (non_osr_flow->failing()) {
   369       record_failure(non_osr_flow->failure_reason());
   370       return NULL;
   371     }
   372     JsrSet* jsrs = new JsrSet(NULL, 16);
   373     Block* non_osr_block = non_osr_flow->existing_block_at(start_bci(), jsrs);
   374     if (non_osr_block == NULL) {
   375       record_failure("cannot reach OSR point");
   376       return NULL;
   377     }
   378     // load up the non-OSR state at this point
   379     non_osr_block->copy_state_into(state);
   380     int non_osr_start = non_osr_block->start();
   381     if (non_osr_start != start_bci()) {
   382       // must flow forward from it
   383       if (CITraceTypeFlow) {
   384         tty->print_cr(">> Interpreting pre-OSR block %d:", non_osr_start);
   385       }
   386       Block* block = block_at(non_osr_start, jsrs);
   387       assert(block->limit() == start_bci(), "must flow forward to start");
   388       flow_block(block, state, jsrs);
   389     }
   390     return state;
   391     // Note:  The code below would be an incorrect for an OSR flow,
   392     // even if it were possible for an OSR entry point to be at bci zero.
   393   }
   394   // "Push" the method signature into the first few locals.
   395   state->set_stack_size(-max_locals());
   396   if (!method()->is_static()) {
   397     state->push(method()->holder());
   398     assert(state->tos() == state->local(0), "");
   399   }
   400   for (ciSignatureStream str(method()->signature());
   401        !str.at_return_type();
   402        str.next()) {
   403     state->push_translate(str.type());
   404   }
   405   // Set the rest of the locals to bottom.
   406   Cell cell = state->next_cell(state->tos());
   407   state->set_stack_size(0);
   408   int limit = state->limit_cell();
   409   for (; cell < limit; cell = state->next_cell(cell)) {
   410     state->set_type_at(cell, state->bottom_type());
   411   }
   412   // Lock an object, if necessary.
   413   state->set_monitor_count(method()->is_synchronized() ? 1 : 0);
   414   return state;
   415 }
   417 // ------------------------------------------------------------------
   418 // ciTypeFlow::StateVector::copy_into
   419 //
   420 // Copy our value into some other StateVector
   421 void ciTypeFlow::StateVector::copy_into(ciTypeFlow::StateVector* copy)
   422 const {
   423   copy->set_stack_size(stack_size());
   424   copy->set_monitor_count(monitor_count());
   425   Cell limit = limit_cell();
   426   for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
   427     copy->set_type_at(c, type_at(c));
   428   }
   429 }
   431 // ------------------------------------------------------------------
   432 // ciTypeFlow::StateVector::meet
   433 //
   434 // Meets this StateVector with another, destructively modifying this
   435 // one.  Returns true if any modification takes place.
   436 bool ciTypeFlow::StateVector::meet(const ciTypeFlow::StateVector* incoming) {
   437   if (monitor_count() == -1) {
   438     set_monitor_count(incoming->monitor_count());
   439   }
   440   assert(monitor_count() == incoming->monitor_count(), "monitors must match");
   442   if (stack_size() == -1) {
   443     set_stack_size(incoming->stack_size());
   444     Cell limit = limit_cell();
   445     #ifdef ASSERT
   446     { for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
   447         assert(type_at(c) == top_type(), "");
   448     } }
   449     #endif
   450     // Make a simple copy of the incoming state.
   451     for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
   452       set_type_at(c, incoming->type_at(c));
   453     }
   454     return true;  // it is always different the first time
   455   }
   456 #ifdef ASSERT
   457   if (stack_size() != incoming->stack_size()) {
   458     _outer->method()->print_codes();
   459     tty->print_cr("!!!! Stack size conflict");
   460     tty->print_cr("Current state:");
   461     print_on(tty);
   462     tty->print_cr("Incoming state:");
   463     ((StateVector*)incoming)->print_on(tty);
   464   }
   465 #endif
   466   assert(stack_size() == incoming->stack_size(), "sanity");
   468   bool different = false;
   469   Cell limit = limit_cell();
   470   for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
   471     ciType* t1 = type_at(c);
   472     ciType* t2 = incoming->type_at(c);
   473     if (!t1->equals(t2)) {
   474       ciType* new_type = type_meet(t1, t2);
   475       if (!t1->equals(new_type)) {
   476         set_type_at(c, new_type);
   477         different = true;
   478       }
   479     }
   480   }
   481   return different;
   482 }
   484 // ------------------------------------------------------------------
   485 // ciTypeFlow::StateVector::meet_exception
   486 //
   487 // Meets this StateVector with another, destructively modifying this
   488 // one.  The incoming state is coming via an exception.  Returns true
   489 // if any modification takes place.
   490 bool ciTypeFlow::StateVector::meet_exception(ciInstanceKlass* exc,
   491                                      const ciTypeFlow::StateVector* incoming) {
   492   if (monitor_count() == -1) {
   493     set_monitor_count(incoming->monitor_count());
   494   }
   495   assert(monitor_count() == incoming->monitor_count(), "monitors must match");
   497   if (stack_size() == -1) {
   498     set_stack_size(1);
   499   }
   501   assert(stack_size() ==  1, "must have one-element stack");
   503   bool different = false;
   505   // Meet locals from incoming array.
   506   Cell limit = local(_outer->max_locals()-1);
   507   for (Cell c = start_cell(); c <= limit; c = next_cell(c)) {
   508     ciType* t1 = type_at(c);
   509     ciType* t2 = incoming->type_at(c);
   510     if (!t1->equals(t2)) {
   511       ciType* new_type = type_meet(t1, t2);
   512       if (!t1->equals(new_type)) {
   513         set_type_at(c, new_type);
   514         different = true;
   515       }
   516     }
   517   }
   519   // Handle stack separately.  When an exception occurs, the
   520   // only stack entry is the exception instance.
   521   ciType* tos_type = type_at_tos();
   522   if (!tos_type->equals(exc)) {
   523     ciType* new_type = type_meet(tos_type, exc);
   524     if (!tos_type->equals(new_type)) {
   525       set_type_at_tos(new_type);
   526       different = true;
   527     }
   528   }
   530   return different;
   531 }
   533 // ------------------------------------------------------------------
   534 // ciTypeFlow::StateVector::push_translate
   535 void ciTypeFlow::StateVector::push_translate(ciType* type) {
   536   BasicType basic_type = type->basic_type();
   537   if (basic_type == T_BOOLEAN || basic_type == T_CHAR ||
   538       basic_type == T_BYTE    || basic_type == T_SHORT) {
   539     push_int();
   540   } else {
   541     push(type);
   542     if (type->is_two_word()) {
   543       push(half_type(type));
   544     }
   545   }
   546 }
   548 // ------------------------------------------------------------------
   549 // ciTypeFlow::StateVector::do_aaload
   550 void ciTypeFlow::StateVector::do_aaload(ciBytecodeStream* str) {
   551   pop_int();
   552   ciObjArrayKlass* array_klass = pop_objArray();
   553   if (array_klass == NULL) {
   554     // Did aaload on a null reference; push a null and ignore the exception.
   555     // This instruction will never continue normally.  All we have to do
   556     // is report a value that will meet correctly with any downstream
   557     // reference types on paths that will truly be executed.  This null type
   558     // meets with any reference type to yield that same reference type.
   559     // (The compiler will generate an unconditional exception here.)
   560     push(null_type());
   561     return;
   562   }
   563   if (!array_klass->is_loaded()) {
   564     // Only fails for some -Xcomp runs
   565     trap(str, array_klass,
   566          Deoptimization::make_trap_request
   567          (Deoptimization::Reason_unloaded,
   568           Deoptimization::Action_reinterpret));
   569     return;
   570   }
   571   ciKlass* element_klass = array_klass->element_klass();
   572   if (!element_klass->is_loaded() && element_klass->is_instance_klass()) {
   573     Untested("unloaded array element class in ciTypeFlow");
   574     trap(str, element_klass,
   575          Deoptimization::make_trap_request
   576          (Deoptimization::Reason_unloaded,
   577           Deoptimization::Action_reinterpret));
   578   } else {
   579     push_object(element_klass);
   580   }
   581 }
   584 // ------------------------------------------------------------------
   585 // ciTypeFlow::StateVector::do_checkcast
   586 void ciTypeFlow::StateVector::do_checkcast(ciBytecodeStream* str) {
   587   bool will_link;
   588   ciKlass* klass = str->get_klass(will_link);
   589   if (!will_link) {
   590     // VM's interpreter will not load 'klass' if object is NULL.
   591     // Type flow after this block may still be needed in two situations:
   592     // 1) C2 uses do_null_assert() and continues compilation for later blocks
   593     // 2) C2 does an OSR compile in a later block (see bug 4778368).
   594     pop_object();
   595     do_null_assert(klass);
   596   } else {
   597     pop_object();
   598     push_object(klass);
   599   }
   600 }
   602 // ------------------------------------------------------------------
   603 // ciTypeFlow::StateVector::do_getfield
   604 void ciTypeFlow::StateVector::do_getfield(ciBytecodeStream* str) {
   605   // could add assert here for type of object.
   606   pop_object();
   607   do_getstatic(str);
   608 }
   610 // ------------------------------------------------------------------
   611 // ciTypeFlow::StateVector::do_getstatic
   612 void ciTypeFlow::StateVector::do_getstatic(ciBytecodeStream* str) {
   613   bool will_link;
   614   ciField* field = str->get_field(will_link);
   615   if (!will_link) {
   616     trap(str, field->holder(), str->get_field_holder_index());
   617   } else {
   618     ciType* field_type = field->type();
   619     if (!field_type->is_loaded()) {
   620       // Normally, we need the field's type to be loaded if we are to
   621       // do anything interesting with its value.
   622       // We used to do this:  trap(str, str->get_field_signature_index());
   623       //
   624       // There is one good reason not to trap here.  Execution can
   625       // get past this "getfield" or "getstatic" if the value of
   626       // the field is null.  As long as the value is null, the class
   627       // does not need to be loaded!  The compiler must assume that
   628       // the value of the unloaded class reference is null; if the code
   629       // ever sees a non-null value, loading has occurred.
   630       //
   631       // This actually happens often enough to be annoying.  If the
   632       // compiler throws an uncommon trap at this bytecode, you can
   633       // get an endless loop of recompilations, when all the code
   634       // needs to do is load a series of null values.  Also, a trap
   635       // here can make an OSR entry point unreachable, triggering the
   636       // assert on non_osr_block in ciTypeFlow::get_start_state.
   637       // (See bug 4379915.)
   638       do_null_assert(field_type->as_klass());
   639     } else {
   640       push_translate(field_type);
   641     }
   642   }
   643 }
   645 // ------------------------------------------------------------------
   646 // ciTypeFlow::StateVector::do_invoke
   647 void ciTypeFlow::StateVector::do_invoke(ciBytecodeStream* str,
   648                                         bool has_receiver) {
   649   bool will_link;
   650   ciSignature* declared_signature = NULL;
   651   ciMethod* callee = str->get_method(will_link, &declared_signature);
   652   assert(declared_signature != NULL, "cannot be null");
   653   if (!will_link) {
   654     // We weren't able to find the method.
   655     if (str->cur_bc() == Bytecodes::_invokedynamic) {
   656       trap(str, NULL,
   657            Deoptimization::make_trap_request
   658            (Deoptimization::Reason_uninitialized,
   659             Deoptimization::Action_reinterpret));
   660     } else {
   661       ciKlass* unloaded_holder = callee->holder();
   662       trap(str, unloaded_holder, str->get_method_holder_index());
   663     }
   664   } else {
   665     // We are using the declared signature here because it might be
   666     // different from the callee signature (Cf. invokedynamic and
   667     // invokehandle).
   668     ciSignatureStream sigstr(declared_signature);
   669     const int arg_size = declared_signature->size();
   670     const int stack_base = stack_size() - arg_size;
   671     int i = 0;
   672     for( ; !sigstr.at_return_type(); sigstr.next()) {
   673       ciType* type = sigstr.type();
   674       ciType* stack_type = type_at(stack(stack_base + i++));
   675       // Do I want to check this type?
   676       // assert(stack_type->is_subtype_of(type), "bad type for field value");
   677       if (type->is_two_word()) {
   678         ciType* stack_type2 = type_at(stack(stack_base + i++));
   679         assert(stack_type2->equals(half_type(type)), "must be 2nd half");
   680       }
   681     }
   682     assert(arg_size == i, "must match");
   683     for (int j = 0; j < arg_size; j++) {
   684       pop();
   685     }
   686     if (has_receiver) {
   687       // Check this?
   688       pop_object();
   689     }
   690     assert(!sigstr.is_done(), "must have return type");
   691     ciType* return_type = sigstr.type();
   692     if (!return_type->is_void()) {
   693       if (!return_type->is_loaded()) {
   694         // As in do_getstatic(), generally speaking, we need the return type to
   695         // be loaded if we are to do anything interesting with its value.
   696         // We used to do this:  trap(str, str->get_method_signature_index());
   697         //
   698         // We do not trap here since execution can get past this invoke if
   699         // the return value is null.  As long as the value is null, the class
   700         // does not need to be loaded!  The compiler must assume that
   701         // the value of the unloaded class reference is null; if the code
   702         // ever sees a non-null value, loading has occurred.
   703         //
   704         // See do_getstatic() for similar explanation, as well as bug 4684993.
   705         do_null_assert(return_type->as_klass());
   706       } else {
   707         push_translate(return_type);
   708       }
   709     }
   710   }
   711 }
   713 // ------------------------------------------------------------------
   714 // ciTypeFlow::StateVector::do_jsr
   715 void ciTypeFlow::StateVector::do_jsr(ciBytecodeStream* str) {
   716   push(ciReturnAddress::make(str->next_bci()));
   717 }
   719 // ------------------------------------------------------------------
   720 // ciTypeFlow::StateVector::do_ldc
   721 void ciTypeFlow::StateVector::do_ldc(ciBytecodeStream* str) {
   722   ciConstant con = str->get_constant();
   723   BasicType basic_type = con.basic_type();
   724   if (basic_type == T_ILLEGAL) {
   725     // OutOfMemoryError in the CI while loading constant
   726     push_null();
   727     outer()->record_failure("ldc did not link");
   728     return;
   729   }
   730   if (basic_type == T_OBJECT || basic_type == T_ARRAY) {
   731     ciObject* obj = con.as_object();
   732     if (obj->is_null_object()) {
   733       push_null();
   734     } else {
   735       assert(obj->is_instance() || obj->is_array(), "must be java_mirror of klass");
   736       push_object(obj->klass());
   737     }
   738   } else {
   739     push_translate(ciType::make(basic_type));
   740   }
   741 }
   743 // ------------------------------------------------------------------
   744 // ciTypeFlow::StateVector::do_multianewarray
   745 void ciTypeFlow::StateVector::do_multianewarray(ciBytecodeStream* str) {
   746   int dimensions = str->get_dimensions();
   747   bool will_link;
   748   ciArrayKlass* array_klass = str->get_klass(will_link)->as_array_klass();
   749   if (!will_link) {
   750     trap(str, array_klass, str->get_klass_index());
   751   } else {
   752     for (int i = 0; i < dimensions; i++) {
   753       pop_int();
   754     }
   755     push_object(array_klass);
   756   }
   757 }
   759 // ------------------------------------------------------------------
   760 // ciTypeFlow::StateVector::do_new
   761 void ciTypeFlow::StateVector::do_new(ciBytecodeStream* str) {
   762   bool will_link;
   763   ciKlass* klass = str->get_klass(will_link);
   764   if (!will_link || str->is_unresolved_klass()) {
   765     trap(str, klass, str->get_klass_index());
   766   } else {
   767     push_object(klass);
   768   }
   769 }
   771 // ------------------------------------------------------------------
   772 // ciTypeFlow::StateVector::do_newarray
   773 void ciTypeFlow::StateVector::do_newarray(ciBytecodeStream* str) {
   774   pop_int();
   775   ciKlass* klass = ciTypeArrayKlass::make((BasicType)str->get_index());
   776   push_object(klass);
   777 }
   779 // ------------------------------------------------------------------
   780 // ciTypeFlow::StateVector::do_putfield
   781 void ciTypeFlow::StateVector::do_putfield(ciBytecodeStream* str) {
   782   do_putstatic(str);
   783   if (_trap_bci != -1)  return;  // unloaded field holder, etc.
   784   // could add assert here for type of object.
   785   pop_object();
   786 }
   788 // ------------------------------------------------------------------
   789 // ciTypeFlow::StateVector::do_putstatic
   790 void ciTypeFlow::StateVector::do_putstatic(ciBytecodeStream* str) {
   791   bool will_link;
   792   ciField* field = str->get_field(will_link);
   793   if (!will_link) {
   794     trap(str, field->holder(), str->get_field_holder_index());
   795   } else {
   796     ciType* field_type = field->type();
   797     ciType* type = pop_value();
   798     // Do I want to check this type?
   799     //      assert(type->is_subtype_of(field_type), "bad type for field value");
   800     if (field_type->is_two_word()) {
   801       ciType* type2 = pop_value();
   802       assert(type2->is_two_word(), "must be 2nd half");
   803       assert(type == half_type(type2), "must be 2nd half");
   804     }
   805   }
   806 }
   808 // ------------------------------------------------------------------
   809 // ciTypeFlow::StateVector::do_ret
   810 void ciTypeFlow::StateVector::do_ret(ciBytecodeStream* str) {
   811   Cell index = local(str->get_index());
   813   ciType* address = type_at(index);
   814   assert(address->is_return_address(), "bad return address");
   815   set_type_at(index, bottom_type());
   816 }
   818 // ------------------------------------------------------------------
   819 // ciTypeFlow::StateVector::trap
   820 //
   821 // Stop interpretation of this path with a trap.
   822 void ciTypeFlow::StateVector::trap(ciBytecodeStream* str, ciKlass* klass, int index) {
   823   _trap_bci = str->cur_bci();
   824   _trap_index = index;
   826   // Log information about this trap:
   827   CompileLog* log = outer()->env()->log();
   828   if (log != NULL) {
   829     int mid = log->identify(outer()->method());
   830     int kid = (klass == NULL)? -1: log->identify(klass);
   831     log->begin_elem("uncommon_trap method='%d' bci='%d'", mid, str->cur_bci());
   832     char buf[100];
   833     log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
   834                                                           index));
   835     if (kid >= 0)
   836       log->print(" klass='%d'", kid);
   837     log->end_elem();
   838   }
   839 }
   841 // ------------------------------------------------------------------
   842 // ciTypeFlow::StateVector::do_null_assert
   843 // Corresponds to graphKit::do_null_assert.
   844 void ciTypeFlow::StateVector::do_null_assert(ciKlass* unloaded_klass) {
   845   if (unloaded_klass->is_loaded()) {
   846     // We failed to link, but we can still compute with this class,
   847     // since it is loaded somewhere.  The compiler will uncommon_trap
   848     // if the object is not null, but the typeflow pass can not assume
   849     // that the object will be null, otherwise it may incorrectly tell
   850     // the parser that an object is known to be null. 4761344, 4807707
   851     push_object(unloaded_klass);
   852   } else {
   853     // The class is not loaded anywhere.  It is safe to model the
   854     // null in the typestates, because we can compile in a null check
   855     // which will deoptimize us if someone manages to load the
   856     // class later.
   857     push_null();
   858   }
   859 }
   862 // ------------------------------------------------------------------
   863 // ciTypeFlow::StateVector::apply_one_bytecode
   864 //
   865 // Apply the effect of one bytecode to this StateVector
   866 bool ciTypeFlow::StateVector::apply_one_bytecode(ciBytecodeStream* str) {
   867   _trap_bci = -1;
   868   _trap_index = 0;
   870   if (CITraceTypeFlow) {
   871     tty->print_cr(">> Interpreting bytecode %d:%s", str->cur_bci(),
   872                   Bytecodes::name(str->cur_bc()));
   873   }
   875   switch(str->cur_bc()) {
   876   case Bytecodes::_aaload: do_aaload(str);                       break;
   878   case Bytecodes::_aastore:
   879     {
   880       pop_object();
   881       pop_int();
   882       pop_objArray();
   883       break;
   884     }
   885   case Bytecodes::_aconst_null:
   886     {
   887       push_null();
   888       break;
   889     }
   890   case Bytecodes::_aload:   load_local_object(str->get_index());    break;
   891   case Bytecodes::_aload_0: load_local_object(0);                   break;
   892   case Bytecodes::_aload_1: load_local_object(1);                   break;
   893   case Bytecodes::_aload_2: load_local_object(2);                   break;
   894   case Bytecodes::_aload_3: load_local_object(3);                   break;
   896   case Bytecodes::_anewarray:
   897     {
   898       pop_int();
   899       bool will_link;
   900       ciKlass* element_klass = str->get_klass(will_link);
   901       if (!will_link) {
   902         trap(str, element_klass, str->get_klass_index());
   903       } else {
   904         push_object(ciObjArrayKlass::make(element_klass));
   905       }
   906       break;
   907     }
   908   case Bytecodes::_areturn:
   909   case Bytecodes::_ifnonnull:
   910   case Bytecodes::_ifnull:
   911     {
   912       pop_object();
   913       break;
   914     }
   915   case Bytecodes::_monitorenter:
   916     {
   917       pop_object();
   918       set_monitor_count(monitor_count() + 1);
   919       break;
   920     }
   921   case Bytecodes::_monitorexit:
   922     {
   923       pop_object();
   924       assert(monitor_count() > 0, "must be a monitor to exit from");
   925       set_monitor_count(monitor_count() - 1);
   926       break;
   927     }
   928   case Bytecodes::_arraylength:
   929     {
   930       pop_array();
   931       push_int();
   932       break;
   933     }
   934   case Bytecodes::_astore:   store_local_object(str->get_index());  break;
   935   case Bytecodes::_astore_0: store_local_object(0);                 break;
   936   case Bytecodes::_astore_1: store_local_object(1);                 break;
   937   case Bytecodes::_astore_2: store_local_object(2);                 break;
   938   case Bytecodes::_astore_3: store_local_object(3);                 break;
   940   case Bytecodes::_athrow:
   941     {
   942       NEEDS_CLEANUP;
   943       pop_object();
   944       break;
   945     }
   946   case Bytecodes::_baload:
   947   case Bytecodes::_caload:
   948   case Bytecodes::_iaload:
   949   case Bytecodes::_saload:
   950     {
   951       pop_int();
   952       ciTypeArrayKlass* array_klass = pop_typeArray();
   953       // Put assert here for right type?
   954       push_int();
   955       break;
   956     }
   957   case Bytecodes::_bastore:
   958   case Bytecodes::_castore:
   959   case Bytecodes::_iastore:
   960   case Bytecodes::_sastore:
   961     {
   962       pop_int();
   963       pop_int();
   964       pop_typeArray();
   965       // assert here?
   966       break;
   967     }
   968   case Bytecodes::_bipush:
   969   case Bytecodes::_iconst_m1:
   970   case Bytecodes::_iconst_0:
   971   case Bytecodes::_iconst_1:
   972   case Bytecodes::_iconst_2:
   973   case Bytecodes::_iconst_3:
   974   case Bytecodes::_iconst_4:
   975   case Bytecodes::_iconst_5:
   976   case Bytecodes::_sipush:
   977     {
   978       push_int();
   979       break;
   980     }
   981   case Bytecodes::_checkcast: do_checkcast(str);                  break;
   983   case Bytecodes::_d2f:
   984     {
   985       pop_double();
   986       push_float();
   987       break;
   988     }
   989   case Bytecodes::_d2i:
   990     {
   991       pop_double();
   992       push_int();
   993       break;
   994     }
   995   case Bytecodes::_d2l:
   996     {
   997       pop_double();
   998       push_long();
   999       break;
  1001   case Bytecodes::_dadd:
  1002   case Bytecodes::_ddiv:
  1003   case Bytecodes::_dmul:
  1004   case Bytecodes::_drem:
  1005   case Bytecodes::_dsub:
  1007       pop_double();
  1008       pop_double();
  1009       push_double();
  1010       break;
  1012   case Bytecodes::_daload:
  1014       pop_int();
  1015       ciTypeArrayKlass* array_klass = pop_typeArray();
  1016       // Put assert here for right type?
  1017       push_double();
  1018       break;
  1020   case Bytecodes::_dastore:
  1022       pop_double();
  1023       pop_int();
  1024       pop_typeArray();
  1025       // assert here?
  1026       break;
  1028   case Bytecodes::_dcmpg:
  1029   case Bytecodes::_dcmpl:
  1031       pop_double();
  1032       pop_double();
  1033       push_int();
  1034       break;
  1036   case Bytecodes::_dconst_0:
  1037   case Bytecodes::_dconst_1:
  1039       push_double();
  1040       break;
  1042   case Bytecodes::_dload:   load_local_double(str->get_index());    break;
  1043   case Bytecodes::_dload_0: load_local_double(0);                   break;
  1044   case Bytecodes::_dload_1: load_local_double(1);                   break;
  1045   case Bytecodes::_dload_2: load_local_double(2);                   break;
  1046   case Bytecodes::_dload_3: load_local_double(3);                   break;
  1048   case Bytecodes::_dneg:
  1050       pop_double();
  1051       push_double();
  1052       break;
  1054   case Bytecodes::_dreturn:
  1056       pop_double();
  1057       break;
  1059   case Bytecodes::_dstore:   store_local_double(str->get_index());  break;
  1060   case Bytecodes::_dstore_0: store_local_double(0);                 break;
  1061   case Bytecodes::_dstore_1: store_local_double(1);                 break;
  1062   case Bytecodes::_dstore_2: store_local_double(2);                 break;
  1063   case Bytecodes::_dstore_3: store_local_double(3);                 break;
  1065   case Bytecodes::_dup:
  1067       push(type_at_tos());
  1068       break;
  1070   case Bytecodes::_dup_x1:
  1072       ciType* value1 = pop_value();
  1073       ciType* value2 = pop_value();
  1074       push(value1);
  1075       push(value2);
  1076       push(value1);
  1077       break;
  1079   case Bytecodes::_dup_x2:
  1081       ciType* value1 = pop_value();
  1082       ciType* value2 = pop_value();
  1083       ciType* value3 = pop_value();
  1084       push(value1);
  1085       push(value3);
  1086       push(value2);
  1087       push(value1);
  1088       break;
  1090   case Bytecodes::_dup2:
  1092       ciType* value1 = pop_value();
  1093       ciType* value2 = pop_value();
  1094       push(value2);
  1095       push(value1);
  1096       push(value2);
  1097       push(value1);
  1098       break;
  1100   case Bytecodes::_dup2_x1:
  1102       ciType* value1 = pop_value();
  1103       ciType* value2 = pop_value();
  1104       ciType* value3 = pop_value();
  1105       push(value2);
  1106       push(value1);
  1107       push(value3);
  1108       push(value2);
  1109       push(value1);
  1110       break;
  1112   case Bytecodes::_dup2_x2:
  1114       ciType* value1 = pop_value();
  1115       ciType* value2 = pop_value();
  1116       ciType* value3 = pop_value();
  1117       ciType* value4 = pop_value();
  1118       push(value2);
  1119       push(value1);
  1120       push(value4);
  1121       push(value3);
  1122       push(value2);
  1123       push(value1);
  1124       break;
  1126   case Bytecodes::_f2d:
  1128       pop_float();
  1129       push_double();
  1130       break;
  1132   case Bytecodes::_f2i:
  1134       pop_float();
  1135       push_int();
  1136       break;
  1138   case Bytecodes::_f2l:
  1140       pop_float();
  1141       push_long();
  1142       break;
  1144   case Bytecodes::_fadd:
  1145   case Bytecodes::_fdiv:
  1146   case Bytecodes::_fmul:
  1147   case Bytecodes::_frem:
  1148   case Bytecodes::_fsub:
  1150       pop_float();
  1151       pop_float();
  1152       push_float();
  1153       break;
  1155   case Bytecodes::_faload:
  1157       pop_int();
  1158       ciTypeArrayKlass* array_klass = pop_typeArray();
  1159       // Put assert here.
  1160       push_float();
  1161       break;
  1163   case Bytecodes::_fastore:
  1165       pop_float();
  1166       pop_int();
  1167       ciTypeArrayKlass* array_klass = pop_typeArray();
  1168       // Put assert here.
  1169       break;
  1171   case Bytecodes::_fcmpg:
  1172   case Bytecodes::_fcmpl:
  1174       pop_float();
  1175       pop_float();
  1176       push_int();
  1177       break;
  1179   case Bytecodes::_fconst_0:
  1180   case Bytecodes::_fconst_1:
  1181   case Bytecodes::_fconst_2:
  1183       push_float();
  1184       break;
  1186   case Bytecodes::_fload:   load_local_float(str->get_index());     break;
  1187   case Bytecodes::_fload_0: load_local_float(0);                    break;
  1188   case Bytecodes::_fload_1: load_local_float(1);                    break;
  1189   case Bytecodes::_fload_2: load_local_float(2);                    break;
  1190   case Bytecodes::_fload_3: load_local_float(3);                    break;
  1192   case Bytecodes::_fneg:
  1194       pop_float();
  1195       push_float();
  1196       break;
  1198   case Bytecodes::_freturn:
  1200       pop_float();
  1201       break;
  1203   case Bytecodes::_fstore:    store_local_float(str->get_index());   break;
  1204   case Bytecodes::_fstore_0:  store_local_float(0);                  break;
  1205   case Bytecodes::_fstore_1:  store_local_float(1);                  break;
  1206   case Bytecodes::_fstore_2:  store_local_float(2);                  break;
  1207   case Bytecodes::_fstore_3:  store_local_float(3);                  break;
  1209   case Bytecodes::_getfield:  do_getfield(str);                      break;
  1210   case Bytecodes::_getstatic: do_getstatic(str);                     break;
  1212   case Bytecodes::_goto:
  1213   case Bytecodes::_goto_w:
  1214   case Bytecodes::_nop:
  1215   case Bytecodes::_return:
  1217       // do nothing.
  1218       break;
  1220   case Bytecodes::_i2b:
  1221   case Bytecodes::_i2c:
  1222   case Bytecodes::_i2s:
  1223   case Bytecodes::_ineg:
  1225       pop_int();
  1226       push_int();
  1227       break;
  1229   case Bytecodes::_i2d:
  1231       pop_int();
  1232       push_double();
  1233       break;
  1235   case Bytecodes::_i2f:
  1237       pop_int();
  1238       push_float();
  1239       break;
  1241   case Bytecodes::_i2l:
  1243       pop_int();
  1244       push_long();
  1245       break;
  1247   case Bytecodes::_iadd:
  1248   case Bytecodes::_iand:
  1249   case Bytecodes::_idiv:
  1250   case Bytecodes::_imul:
  1251   case Bytecodes::_ior:
  1252   case Bytecodes::_irem:
  1253   case Bytecodes::_ishl:
  1254   case Bytecodes::_ishr:
  1255   case Bytecodes::_isub:
  1256   case Bytecodes::_iushr:
  1257   case Bytecodes::_ixor:
  1259       pop_int();
  1260       pop_int();
  1261       push_int();
  1262       break;
  1264   case Bytecodes::_if_acmpeq:
  1265   case Bytecodes::_if_acmpne:
  1267       pop_object();
  1268       pop_object();
  1269       break;
  1271   case Bytecodes::_if_icmpeq:
  1272   case Bytecodes::_if_icmpge:
  1273   case Bytecodes::_if_icmpgt:
  1274   case Bytecodes::_if_icmple:
  1275   case Bytecodes::_if_icmplt:
  1276   case Bytecodes::_if_icmpne:
  1278       pop_int();
  1279       pop_int();
  1280       break;
  1282   case Bytecodes::_ifeq:
  1283   case Bytecodes::_ifle:
  1284   case Bytecodes::_iflt:
  1285   case Bytecodes::_ifge:
  1286   case Bytecodes::_ifgt:
  1287   case Bytecodes::_ifne:
  1288   case Bytecodes::_ireturn:
  1289   case Bytecodes::_lookupswitch:
  1290   case Bytecodes::_tableswitch:
  1292       pop_int();
  1293       break;
  1295   case Bytecodes::_iinc:
  1297       int lnum = str->get_index();
  1298       check_int(local(lnum));
  1299       store_to_local(lnum);
  1300       break;
  1302   case Bytecodes::_iload:   load_local_int(str->get_index()); break;
  1303   case Bytecodes::_iload_0: load_local_int(0);                      break;
  1304   case Bytecodes::_iload_1: load_local_int(1);                      break;
  1305   case Bytecodes::_iload_2: load_local_int(2);                      break;
  1306   case Bytecodes::_iload_3: load_local_int(3);                      break;
  1308   case Bytecodes::_instanceof:
  1310       // Check for uncommon trap:
  1311       do_checkcast(str);
  1312       pop_object();
  1313       push_int();
  1314       break;
  1316   case Bytecodes::_invokeinterface: do_invoke(str, true);           break;
  1317   case Bytecodes::_invokespecial:   do_invoke(str, true);           break;
  1318   case Bytecodes::_invokestatic:    do_invoke(str, false);          break;
  1319   case Bytecodes::_invokevirtual:   do_invoke(str, true);           break;
  1320   case Bytecodes::_invokedynamic:   do_invoke(str, false);          break;
  1322   case Bytecodes::_istore:   store_local_int(str->get_index());     break;
  1323   case Bytecodes::_istore_0: store_local_int(0);                    break;
  1324   case Bytecodes::_istore_1: store_local_int(1);                    break;
  1325   case Bytecodes::_istore_2: store_local_int(2);                    break;
  1326   case Bytecodes::_istore_3: store_local_int(3);                    break;
  1328   case Bytecodes::_jsr:
  1329   case Bytecodes::_jsr_w: do_jsr(str);                              break;
  1331   case Bytecodes::_l2d:
  1333       pop_long();
  1334       push_double();
  1335       break;
  1337   case Bytecodes::_l2f:
  1339       pop_long();
  1340       push_float();
  1341       break;
  1343   case Bytecodes::_l2i:
  1345       pop_long();
  1346       push_int();
  1347       break;
  1349   case Bytecodes::_ladd:
  1350   case Bytecodes::_land:
  1351   case Bytecodes::_ldiv:
  1352   case Bytecodes::_lmul:
  1353   case Bytecodes::_lor:
  1354   case Bytecodes::_lrem:
  1355   case Bytecodes::_lsub:
  1356   case Bytecodes::_lxor:
  1358       pop_long();
  1359       pop_long();
  1360       push_long();
  1361       break;
  1363   case Bytecodes::_laload:
  1365       pop_int();
  1366       ciTypeArrayKlass* array_klass = pop_typeArray();
  1367       // Put assert here for right type?
  1368       push_long();
  1369       break;
  1371   case Bytecodes::_lastore:
  1373       pop_long();
  1374       pop_int();
  1375       pop_typeArray();
  1376       // assert here?
  1377       break;
  1379   case Bytecodes::_lcmp:
  1381       pop_long();
  1382       pop_long();
  1383       push_int();
  1384       break;
  1386   case Bytecodes::_lconst_0:
  1387   case Bytecodes::_lconst_1:
  1389       push_long();
  1390       break;
  1392   case Bytecodes::_ldc:
  1393   case Bytecodes::_ldc_w:
  1394   case Bytecodes::_ldc2_w:
  1396       do_ldc(str);
  1397       break;
  1400   case Bytecodes::_lload:   load_local_long(str->get_index());      break;
  1401   case Bytecodes::_lload_0: load_local_long(0);                     break;
  1402   case Bytecodes::_lload_1: load_local_long(1);                     break;
  1403   case Bytecodes::_lload_2: load_local_long(2);                     break;
  1404   case Bytecodes::_lload_3: load_local_long(3);                     break;
  1406   case Bytecodes::_lneg:
  1408       pop_long();
  1409       push_long();
  1410       break;
  1412   case Bytecodes::_lreturn:
  1414       pop_long();
  1415       break;
  1417   case Bytecodes::_lshl:
  1418   case Bytecodes::_lshr:
  1419   case Bytecodes::_lushr:
  1421       pop_int();
  1422       pop_long();
  1423       push_long();
  1424       break;
  1426   case Bytecodes::_lstore:   store_local_long(str->get_index());    break;
  1427   case Bytecodes::_lstore_0: store_local_long(0);                   break;
  1428   case Bytecodes::_lstore_1: store_local_long(1);                   break;
  1429   case Bytecodes::_lstore_2: store_local_long(2);                   break;
  1430   case Bytecodes::_lstore_3: store_local_long(3);                   break;
  1432   case Bytecodes::_multianewarray: do_multianewarray(str);          break;
  1434   case Bytecodes::_new:      do_new(str);                           break;
  1436   case Bytecodes::_newarray: do_newarray(str);                      break;
  1438   case Bytecodes::_pop:
  1440       pop();
  1441       break;
  1443   case Bytecodes::_pop2:
  1445       pop();
  1446       pop();
  1447       break;
  1450   case Bytecodes::_putfield:       do_putfield(str);                 break;
  1451   case Bytecodes::_putstatic:      do_putstatic(str);                break;
  1453   case Bytecodes::_ret: do_ret(str);                                 break;
  1455   case Bytecodes::_swap:
  1457       ciType* value1 = pop_value();
  1458       ciType* value2 = pop_value();
  1459       push(value1);
  1460       push(value2);
  1461       break;
  1463   case Bytecodes::_wide:
  1464   default:
  1466       // The iterator should skip this.
  1467       ShouldNotReachHere();
  1468       break;
  1472   if (CITraceTypeFlow) {
  1473     print_on(tty);
  1476   return (_trap_bci != -1);
  1479 #ifndef PRODUCT
  1480 // ------------------------------------------------------------------
  1481 // ciTypeFlow::StateVector::print_cell_on
  1482 void ciTypeFlow::StateVector::print_cell_on(outputStream* st, Cell c) const {
  1483   ciType* type = type_at(c);
  1484   if (type == top_type()) {
  1485     st->print("top");
  1486   } else if (type == bottom_type()) {
  1487     st->print("bottom");
  1488   } else if (type == null_type()) {
  1489     st->print("null");
  1490   } else if (type == long2_type()) {
  1491     st->print("long2");
  1492   } else if (type == double2_type()) {
  1493     st->print("double2");
  1494   } else if (is_int(type)) {
  1495     st->print("int");
  1496   } else if (is_long(type)) {
  1497     st->print("long");
  1498   } else if (is_float(type)) {
  1499     st->print("float");
  1500   } else if (is_double(type)) {
  1501     st->print("double");
  1502   } else if (type->is_return_address()) {
  1503     st->print("address(%d)", type->as_return_address()->bci());
  1504   } else {
  1505     if (type->is_klass()) {
  1506       type->as_klass()->name()->print_symbol_on(st);
  1507     } else {
  1508       st->print("UNEXPECTED TYPE");
  1509       type->print();
  1514 // ------------------------------------------------------------------
  1515 // ciTypeFlow::StateVector::print_on
  1516 void ciTypeFlow::StateVector::print_on(outputStream* st) const {
  1517   int num_locals   = _outer->max_locals();
  1518   int num_stack    = stack_size();
  1519   int num_monitors = monitor_count();
  1520   st->print_cr("  State : locals %d, stack %d, monitors %d", num_locals, num_stack, num_monitors);
  1521   if (num_stack >= 0) {
  1522     int i;
  1523     for (i = 0; i < num_locals; i++) {
  1524       st->print("    local %2d : ", i);
  1525       print_cell_on(st, local(i));
  1526       st->cr();
  1528     for (i = 0; i < num_stack; i++) {
  1529       st->print("    stack %2d : ", i);
  1530       print_cell_on(st, stack(i));
  1531       st->cr();
  1535 #endif
  1538 // ------------------------------------------------------------------
  1539 // ciTypeFlow::SuccIter::next
  1540 //
  1541 void ciTypeFlow::SuccIter::next() {
  1542   int succ_ct = _pred->successors()->length();
  1543   int next = _index + 1;
  1544   if (next < succ_ct) {
  1545     _index = next;
  1546     _succ = _pred->successors()->at(next);
  1547     return;
  1549   for (int i = next - succ_ct; i < _pred->exceptions()->length(); i++) {
  1550     // Do not compile any code for unloaded exception types.
  1551     // Following compiler passes are responsible for doing this also.
  1552     ciInstanceKlass* exception_klass = _pred->exc_klasses()->at(i);
  1553     if (exception_klass->is_loaded()) {
  1554       _index = next;
  1555       _succ = _pred->exceptions()->at(i);
  1556       return;
  1558     next++;
  1560   _index = -1;
  1561   _succ = NULL;
  1564 // ------------------------------------------------------------------
  1565 // ciTypeFlow::SuccIter::set_succ
  1566 //
  1567 void ciTypeFlow::SuccIter::set_succ(Block* succ) {
  1568   int succ_ct = _pred->successors()->length();
  1569   if (_index < succ_ct) {
  1570     _pred->successors()->at_put(_index, succ);
  1571   } else {
  1572     int idx = _index - succ_ct;
  1573     _pred->exceptions()->at_put(idx, succ);
  1577 // ciTypeFlow::Block
  1578 //
  1579 // A basic block.
  1581 // ------------------------------------------------------------------
  1582 // ciTypeFlow::Block::Block
  1583 ciTypeFlow::Block::Block(ciTypeFlow* outer,
  1584                          ciBlock *ciblk,
  1585                          ciTypeFlow::JsrSet* jsrs) {
  1586   _ciblock = ciblk;
  1587   _exceptions = NULL;
  1588   _exc_klasses = NULL;
  1589   _successors = NULL;
  1590   _state = new (outer->arena()) StateVector(outer);
  1591   JsrSet* new_jsrs =
  1592     new (outer->arena()) JsrSet(outer->arena(), jsrs->size());
  1593   jsrs->copy_into(new_jsrs);
  1594   _jsrs = new_jsrs;
  1595   _next = NULL;
  1596   _on_work_list = false;
  1597   _backedge_copy = false;
  1598   _has_monitorenter = false;
  1599   _trap_bci = -1;
  1600   _trap_index = 0;
  1601   df_init();
  1603   if (CITraceTypeFlow) {
  1604     tty->print_cr(">> Created new block");
  1605     print_on(tty);
  1608   assert(this->outer() == outer, "outer link set up");
  1609   assert(!outer->have_block_count(), "must not have mapped blocks yet");
  1612 // ------------------------------------------------------------------
  1613 // ciTypeFlow::Block::df_init
  1614 void ciTypeFlow::Block::df_init() {
  1615   _pre_order = -1; assert(!has_pre_order(), "");
  1616   _post_order = -1; assert(!has_post_order(), "");
  1617   _loop = NULL;
  1618   _irreducible_entry = false;
  1619   _rpo_next = NULL;
  1622 // ------------------------------------------------------------------
  1623 // ciTypeFlow::Block::successors
  1624 //
  1625 // Get the successors for this Block.
  1626 GrowableArray<ciTypeFlow::Block*>*
  1627 ciTypeFlow::Block::successors(ciBytecodeStream* str,
  1628                               ciTypeFlow::StateVector* state,
  1629                               ciTypeFlow::JsrSet* jsrs) {
  1630   if (_successors == NULL) {
  1631     if (CITraceTypeFlow) {
  1632       tty->print(">> Computing successors for block ");
  1633       print_value_on(tty);
  1634       tty->cr();
  1637     ciTypeFlow* analyzer = outer();
  1638     Arena* arena = analyzer->arena();
  1639     Block* block = NULL;
  1640     bool has_successor = !has_trap() &&
  1641                          (control() != ciBlock::fall_through_bci || limit() < analyzer->code_size());
  1642     if (!has_successor) {
  1643       _successors =
  1644         new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
  1645       // No successors
  1646     } else if (control() == ciBlock::fall_through_bci) {
  1647       assert(str->cur_bci() == limit(), "bad block end");
  1648       // This block simply falls through to the next.
  1649       _successors =
  1650         new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
  1652       Block* block = analyzer->block_at(limit(), _jsrs);
  1653       assert(_successors->length() == FALL_THROUGH, "");
  1654       _successors->append(block);
  1655     } else {
  1656       int current_bci = str->cur_bci();
  1657       int next_bci = str->next_bci();
  1658       int branch_bci = -1;
  1659       Block* target = NULL;
  1660       assert(str->next_bci() == limit(), "bad block end");
  1661       // This block is not a simple fall-though.  Interpret
  1662       // the current bytecode to find our successors.
  1663       switch (str->cur_bc()) {
  1664       case Bytecodes::_ifeq:         case Bytecodes::_ifne:
  1665       case Bytecodes::_iflt:         case Bytecodes::_ifge:
  1666       case Bytecodes::_ifgt:         case Bytecodes::_ifle:
  1667       case Bytecodes::_if_icmpeq:    case Bytecodes::_if_icmpne:
  1668       case Bytecodes::_if_icmplt:    case Bytecodes::_if_icmpge:
  1669       case Bytecodes::_if_icmpgt:    case Bytecodes::_if_icmple:
  1670       case Bytecodes::_if_acmpeq:    case Bytecodes::_if_acmpne:
  1671       case Bytecodes::_ifnull:       case Bytecodes::_ifnonnull:
  1672         // Our successors are the branch target and the next bci.
  1673         branch_bci = str->get_dest();
  1674         _successors =
  1675           new (arena) GrowableArray<Block*>(arena, 2, 0, NULL);
  1676         assert(_successors->length() == IF_NOT_TAKEN, "");
  1677         _successors->append(analyzer->block_at(next_bci, jsrs));
  1678         assert(_successors->length() == IF_TAKEN, "");
  1679         _successors->append(analyzer->block_at(branch_bci, jsrs));
  1680         break;
  1682       case Bytecodes::_goto:
  1683         branch_bci = str->get_dest();
  1684         _successors =
  1685           new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
  1686         assert(_successors->length() == GOTO_TARGET, "");
  1687         _successors->append(analyzer->block_at(branch_bci, jsrs));
  1688         break;
  1690       case Bytecodes::_jsr:
  1691         branch_bci = str->get_dest();
  1692         _successors =
  1693           new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
  1694         assert(_successors->length() == GOTO_TARGET, "");
  1695         _successors->append(analyzer->block_at(branch_bci, jsrs));
  1696         break;
  1698       case Bytecodes::_goto_w:
  1699       case Bytecodes::_jsr_w:
  1700         _successors =
  1701           new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
  1702         assert(_successors->length() == GOTO_TARGET, "");
  1703         _successors->append(analyzer->block_at(str->get_far_dest(), jsrs));
  1704         break;
  1706       case Bytecodes::_tableswitch:  {
  1707         Bytecode_tableswitch tableswitch(str);
  1709         int len = tableswitch.length();
  1710         _successors =
  1711           new (arena) GrowableArray<Block*>(arena, len+1, 0, NULL);
  1712         int bci = current_bci + tableswitch.default_offset();
  1713         Block* block = analyzer->block_at(bci, jsrs);
  1714         assert(_successors->length() == SWITCH_DEFAULT, "");
  1715         _successors->append(block);
  1716         while (--len >= 0) {
  1717           int bci = current_bci + tableswitch.dest_offset_at(len);
  1718           block = analyzer->block_at(bci, jsrs);
  1719           assert(_successors->length() >= SWITCH_CASES, "");
  1720           _successors->append_if_missing(block);
  1722         break;
  1725       case Bytecodes::_lookupswitch: {
  1726         Bytecode_lookupswitch lookupswitch(str);
  1728         int npairs = lookupswitch.number_of_pairs();
  1729         _successors =
  1730           new (arena) GrowableArray<Block*>(arena, npairs+1, 0, NULL);
  1731         int bci = current_bci + lookupswitch.default_offset();
  1732         Block* block = analyzer->block_at(bci, jsrs);
  1733         assert(_successors->length() == SWITCH_DEFAULT, "");
  1734         _successors->append(block);
  1735         while(--npairs >= 0) {
  1736           LookupswitchPair pair = lookupswitch.pair_at(npairs);
  1737           int bci = current_bci + pair.offset();
  1738           Block* block = analyzer->block_at(bci, jsrs);
  1739           assert(_successors->length() >= SWITCH_CASES, "");
  1740           _successors->append_if_missing(block);
  1742         break;
  1745       case Bytecodes::_athrow:     case Bytecodes::_ireturn:
  1746       case Bytecodes::_lreturn:    case Bytecodes::_freturn:
  1747       case Bytecodes::_dreturn:    case Bytecodes::_areturn:
  1748       case Bytecodes::_return:
  1749         _successors =
  1750           new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
  1751         // No successors
  1752         break;
  1754       case Bytecodes::_ret: {
  1755         _successors =
  1756           new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
  1758         Cell local = state->local(str->get_index());
  1759         ciType* return_address = state->type_at(local);
  1760         assert(return_address->is_return_address(), "verify: wrong type");
  1761         int bci = return_address->as_return_address()->bci();
  1762         assert(_successors->length() == GOTO_TARGET, "");
  1763         _successors->append(analyzer->block_at(bci, jsrs));
  1764         break;
  1767       case Bytecodes::_wide:
  1768       default:
  1769         ShouldNotReachHere();
  1770         break;
  1774   return _successors;
  1777 // ------------------------------------------------------------------
  1778 // ciTypeFlow::Block:compute_exceptions
  1779 //
  1780 // Compute the exceptional successors and types for this Block.
  1781 void ciTypeFlow::Block::compute_exceptions() {
  1782   assert(_exceptions == NULL && _exc_klasses == NULL, "repeat");
  1784   if (CITraceTypeFlow) {
  1785     tty->print(">> Computing exceptions for block ");
  1786     print_value_on(tty);
  1787     tty->cr();
  1790   ciTypeFlow* analyzer = outer();
  1791   Arena* arena = analyzer->arena();
  1793   // Any bci in the block will do.
  1794   ciExceptionHandlerStream str(analyzer->method(), start());
  1796   // Allocate our growable arrays.
  1797   int exc_count = str.count();
  1798   _exceptions = new (arena) GrowableArray<Block*>(arena, exc_count, 0, NULL);
  1799   _exc_klasses = new (arena) GrowableArray<ciInstanceKlass*>(arena, exc_count,
  1800                                                              0, NULL);
  1802   for ( ; !str.is_done(); str.next()) {
  1803     ciExceptionHandler* handler = str.handler();
  1804     int bci = handler->handler_bci();
  1805     ciInstanceKlass* klass = NULL;
  1806     if (bci == -1) {
  1807       // There is no catch all.  It is possible to exit the method.
  1808       break;
  1810     if (handler->is_catch_all()) {
  1811       klass = analyzer->env()->Throwable_klass();
  1812     } else {
  1813       klass = handler->catch_klass();
  1815     _exceptions->append(analyzer->block_at(bci, _jsrs));
  1816     _exc_klasses->append(klass);
  1820 // ------------------------------------------------------------------
  1821 // ciTypeFlow::Block::set_backedge_copy
  1822 // Use this only to make a pre-existing public block into a backedge copy.
  1823 void ciTypeFlow::Block::set_backedge_copy(bool z) {
  1824   assert(z || (z == is_backedge_copy()), "cannot make a backedge copy public");
  1825   _backedge_copy = z;
  1828 // ------------------------------------------------------------------
  1829 // ciTypeFlow::Block::is_clonable_exit
  1830 //
  1831 // At most 2 normal successors, one of which continues looping,
  1832 // and all exceptional successors must exit.
  1833 bool ciTypeFlow::Block::is_clonable_exit(ciTypeFlow::Loop* lp) {
  1834   int normal_cnt  = 0;
  1835   int in_loop_cnt = 0;
  1836   for (SuccIter iter(this); !iter.done(); iter.next()) {
  1837     Block* succ = iter.succ();
  1838     if (iter.is_normal_ctrl()) {
  1839       if (++normal_cnt > 2) return false;
  1840       if (lp->contains(succ->loop())) {
  1841         if (++in_loop_cnt > 1) return false;
  1843     } else {
  1844       if (lp->contains(succ->loop())) return false;
  1847   return in_loop_cnt == 1;
  1850 // ------------------------------------------------------------------
  1851 // ciTypeFlow::Block::looping_succ
  1852 //
  1853 ciTypeFlow::Block* ciTypeFlow::Block::looping_succ(ciTypeFlow::Loop* lp) {
  1854   assert(successors()->length() <= 2, "at most 2 normal successors");
  1855   for (SuccIter iter(this); !iter.done(); iter.next()) {
  1856     Block* succ = iter.succ();
  1857     if (lp->contains(succ->loop())) {
  1858       return succ;
  1861   return NULL;
  1864 #ifndef PRODUCT
  1865 // ------------------------------------------------------------------
  1866 // ciTypeFlow::Block::print_value_on
  1867 void ciTypeFlow::Block::print_value_on(outputStream* st) const {
  1868   if (has_pre_order()) st->print("#%-2d ", pre_order());
  1869   if (has_rpo())       st->print("rpo#%-2d ", rpo());
  1870   st->print("[%d - %d)", start(), limit());
  1871   if (is_loop_head()) st->print(" lphd");
  1872   if (is_irreducible_entry()) st->print(" irred");
  1873   if (_jsrs->size() > 0) { st->print("/");  _jsrs->print_on(st); }
  1874   if (is_backedge_copy())  st->print("/backedge_copy");
  1877 // ------------------------------------------------------------------
  1878 // ciTypeFlow::Block::print_on
  1879 void ciTypeFlow::Block::print_on(outputStream* st) const {
  1880   if ((Verbose || WizardMode) && (limit() >= 0)) {
  1881     // Don't print 'dummy' blocks (i.e. blocks with limit() '-1')
  1882     outer()->method()->print_codes_on(start(), limit(), st);
  1884   st->print_cr("  ====================================================  ");
  1885   st->print ("  ");
  1886   print_value_on(st);
  1887   st->print(" Stored locals: "); def_locals()->print_on(st, outer()->method()->max_locals()); tty->cr();
  1888   if (loop() && loop()->parent() != NULL) {
  1889     st->print(" loops:");
  1890     Loop* lp = loop();
  1891     do {
  1892       st->print(" %d<-%d", lp->head()->pre_order(),lp->tail()->pre_order());
  1893       if (lp->is_irreducible()) st->print("(ir)");
  1894       lp = lp->parent();
  1895     } while (lp->parent() != NULL);
  1897   st->cr();
  1898   _state->print_on(st);
  1899   if (_successors == NULL) {
  1900     st->print_cr("  No successor information");
  1901   } else {
  1902     int num_successors = _successors->length();
  1903     st->print_cr("  Successors : %d", num_successors);
  1904     for (int i = 0; i < num_successors; i++) {
  1905       Block* successor = _successors->at(i);
  1906       st->print("    ");
  1907       successor->print_value_on(st);
  1908       st->cr();
  1911   if (_exceptions == NULL) {
  1912     st->print_cr("  No exception information");
  1913   } else {
  1914     int num_exceptions = _exceptions->length();
  1915     st->print_cr("  Exceptions : %d", num_exceptions);
  1916     for (int i = 0; i < num_exceptions; i++) {
  1917       Block* exc_succ = _exceptions->at(i);
  1918       ciInstanceKlass* exc_klass = _exc_klasses->at(i);
  1919       st->print("    ");
  1920       exc_succ->print_value_on(st);
  1921       st->print(" -- ");
  1922       exc_klass->name()->print_symbol_on(st);
  1923       st->cr();
  1926   if (has_trap()) {
  1927     st->print_cr("  Traps on %d with trap index %d", trap_bci(), trap_index());
  1929   st->print_cr("  ====================================================  ");
  1931 #endif
  1933 #ifndef PRODUCT
  1934 // ------------------------------------------------------------------
  1935 // ciTypeFlow::LocalSet::print_on
  1936 void ciTypeFlow::LocalSet::print_on(outputStream* st, int limit) const {
  1937   st->print("{");
  1938   for (int i = 0; i < max; i++) {
  1939     if (test(i)) st->print(" %d", i);
  1941   if (limit > max) {
  1942     st->print(" %d..%d ", max, limit);
  1944   st->print(" }");
  1946 #endif
  1948 // ciTypeFlow
  1949 //
  1950 // This is a pass over the bytecodes which computes the following:
  1951 //   basic block structure
  1952 //   interpreter type-states (a la the verifier)
  1954 // ------------------------------------------------------------------
  1955 // ciTypeFlow::ciTypeFlow
  1956 ciTypeFlow::ciTypeFlow(ciEnv* env, ciMethod* method, int osr_bci) {
  1957   _env = env;
  1958   _method = method;
  1959   _methodBlocks = method->get_method_blocks();
  1960   _max_locals = method->max_locals();
  1961   _max_stack = method->max_stack();
  1962   _code_size = method->code_size();
  1963   _has_irreducible_entry = false;
  1964   _osr_bci = osr_bci;
  1965   _failure_reason = NULL;
  1966   assert(0 <= start_bci() && start_bci() < code_size() , err_msg("correct osr_bci argument: 0 <= %d < %d", start_bci(), code_size()));
  1967   _work_list = NULL;
  1969   _ciblock_count = _methodBlocks->num_blocks();
  1970   _idx_to_blocklist = NEW_ARENA_ARRAY(arena(), GrowableArray<Block*>*, _ciblock_count);
  1971   for (int i = 0; i < _ciblock_count; i++) {
  1972     _idx_to_blocklist[i] = NULL;
  1974   _block_map = NULL;  // until all blocks are seen
  1975   _jsr_count = 0;
  1976   _jsr_records = NULL;
  1979 // ------------------------------------------------------------------
  1980 // ciTypeFlow::work_list_next
  1981 //
  1982 // Get the next basic block from our work list.
  1983 ciTypeFlow::Block* ciTypeFlow::work_list_next() {
  1984   assert(!work_list_empty(), "work list must not be empty");
  1985   Block* next_block = _work_list;
  1986   _work_list = next_block->next();
  1987   next_block->set_next(NULL);
  1988   next_block->set_on_work_list(false);
  1989   return next_block;
  1992 // ------------------------------------------------------------------
  1993 // ciTypeFlow::add_to_work_list
  1994 //
  1995 // Add a basic block to our work list.
  1996 // List is sorted by decreasing postorder sort (same as increasing RPO)
  1997 void ciTypeFlow::add_to_work_list(ciTypeFlow::Block* block) {
  1998   assert(!block->is_on_work_list(), "must not already be on work list");
  2000   if (CITraceTypeFlow) {
  2001     tty->print(">> Adding block ");
  2002     block->print_value_on(tty);
  2003     tty->print_cr(" to the work list : ");
  2006   block->set_on_work_list(true);
  2008   // decreasing post order sort
  2010   Block* prev = NULL;
  2011   Block* current = _work_list;
  2012   int po = block->post_order();
  2013   while (current != NULL) {
  2014     if (!current->has_post_order() || po > current->post_order())
  2015       break;
  2016     prev = current;
  2017     current = current->next();
  2019   if (prev == NULL) {
  2020     block->set_next(_work_list);
  2021     _work_list = block;
  2022   } else {
  2023     block->set_next(current);
  2024     prev->set_next(block);
  2027   if (CITraceTypeFlow) {
  2028     tty->cr();
  2032 // ------------------------------------------------------------------
  2033 // ciTypeFlow::block_at
  2034 //
  2035 // Return the block beginning at bci which has a JsrSet compatible
  2036 // with jsrs.
  2037 ciTypeFlow::Block* ciTypeFlow::block_at(int bci, ciTypeFlow::JsrSet* jsrs, CreateOption option) {
  2038   // First find the right ciBlock.
  2039   if (CITraceTypeFlow) {
  2040     tty->print(">> Requesting block for %d/", bci);
  2041     jsrs->print_on(tty);
  2042     tty->cr();
  2045   ciBlock* ciblk = _methodBlocks->block_containing(bci);
  2046   assert(ciblk->start_bci() == bci, "bad ciBlock boundaries");
  2047   Block* block = get_block_for(ciblk->index(), jsrs, option);
  2049   assert(block == NULL? (option == no_create): block->is_backedge_copy() == (option == create_backedge_copy), "create option consistent with result");
  2051   if (CITraceTypeFlow) {
  2052     if (block != NULL) {
  2053       tty->print(">> Found block ");
  2054       block->print_value_on(tty);
  2055       tty->cr();
  2056     } else {
  2057       tty->print_cr(">> No such block.");
  2061   return block;
  2064 // ------------------------------------------------------------------
  2065 // ciTypeFlow::make_jsr_record
  2066 //
  2067 // Make a JsrRecord for a given (entry, return) pair, if such a record
  2068 // does not already exist.
  2069 ciTypeFlow::JsrRecord* ciTypeFlow::make_jsr_record(int entry_address,
  2070                                                    int return_address) {
  2071   if (_jsr_records == NULL) {
  2072     _jsr_records = new (arena()) GrowableArray<JsrRecord*>(arena(),
  2073                                                            _jsr_count,
  2074                                                            0,
  2075                                                            NULL);
  2077   JsrRecord* record = NULL;
  2078   int len = _jsr_records->length();
  2079   for (int i = 0; i < len; i++) {
  2080     JsrRecord* record = _jsr_records->at(i);
  2081     if (record->entry_address() == entry_address &&
  2082         record->return_address() == return_address) {
  2083       return record;
  2087   record = new (arena()) JsrRecord(entry_address, return_address);
  2088   _jsr_records->append(record);
  2089   return record;
  2092 // ------------------------------------------------------------------
  2093 // ciTypeFlow::flow_exceptions
  2094 //
  2095 // Merge the current state into all exceptional successors at the
  2096 // current point in the code.
  2097 void ciTypeFlow::flow_exceptions(GrowableArray<ciTypeFlow::Block*>* exceptions,
  2098                                  GrowableArray<ciInstanceKlass*>* exc_klasses,
  2099                                  ciTypeFlow::StateVector* state) {
  2100   int len = exceptions->length();
  2101   assert(exc_klasses->length() == len, "must have same length");
  2102   for (int i = 0; i < len; i++) {
  2103     Block* block = exceptions->at(i);
  2104     ciInstanceKlass* exception_klass = exc_klasses->at(i);
  2106     if (!exception_klass->is_loaded()) {
  2107       // Do not compile any code for unloaded exception types.
  2108       // Following compiler passes are responsible for doing this also.
  2109       continue;
  2112     if (block->meet_exception(exception_klass, state)) {
  2113       // Block was modified and has PO.  Add it to the work list.
  2114       if (block->has_post_order() &&
  2115           !block->is_on_work_list()) {
  2116         add_to_work_list(block);
  2122 // ------------------------------------------------------------------
  2123 // ciTypeFlow::flow_successors
  2124 //
  2125 // Merge the current state into all successors at the current point
  2126 // in the code.
  2127 void ciTypeFlow::flow_successors(GrowableArray<ciTypeFlow::Block*>* successors,
  2128                                  ciTypeFlow::StateVector* state) {
  2129   int len = successors->length();
  2130   for (int i = 0; i < len; i++) {
  2131     Block* block = successors->at(i);
  2132     if (block->meet(state)) {
  2133       // Block was modified and has PO.  Add it to the work list.
  2134       if (block->has_post_order() &&
  2135           !block->is_on_work_list()) {
  2136         add_to_work_list(block);
  2142 // ------------------------------------------------------------------
  2143 // ciTypeFlow::can_trap
  2144 //
  2145 // Tells if a given instruction is able to generate an exception edge.
  2146 bool ciTypeFlow::can_trap(ciBytecodeStream& str) {
  2147   // Cf. GenerateOopMap::do_exception_edge.
  2148   if (!Bytecodes::can_trap(str.cur_bc()))  return false;
  2150   switch (str.cur_bc()) {
  2151     // %%% FIXME: ldc of Class can generate an exception
  2152     case Bytecodes::_ldc:
  2153     case Bytecodes::_ldc_w:
  2154     case Bytecodes::_ldc2_w:
  2155     case Bytecodes::_aload_0:
  2156       // These bytecodes can trap for rewriting.  We need to assume that
  2157       // they do not throw exceptions to make the monitor analysis work.
  2158       return false;
  2160     case Bytecodes::_ireturn:
  2161     case Bytecodes::_lreturn:
  2162     case Bytecodes::_freturn:
  2163     case Bytecodes::_dreturn:
  2164     case Bytecodes::_areturn:
  2165     case Bytecodes::_return:
  2166       // We can assume the monitor stack is empty in this analysis.
  2167       return false;
  2169     case Bytecodes::_monitorexit:
  2170       // We can assume monitors are matched in this analysis.
  2171       return false;
  2174   return true;
  2177 // ------------------------------------------------------------------
  2178 // ciTypeFlow::clone_loop_heads
  2179 //
  2180 // Clone the loop heads
  2181 bool ciTypeFlow::clone_loop_heads(Loop* lp, StateVector* temp_vector, JsrSet* temp_set) {
  2182   bool rslt = false;
  2183   for (PreorderLoops iter(loop_tree_root()); !iter.done(); iter.next()) {
  2184     lp = iter.current();
  2185     Block* head = lp->head();
  2186     if (lp == loop_tree_root() ||
  2187         lp->is_irreducible() ||
  2188         !head->is_clonable_exit(lp))
  2189       continue;
  2191     // Avoid BoxLock merge.
  2192     if (EliminateNestedLocks && head->has_monitorenter())
  2193       continue;
  2195     // check not already cloned
  2196     if (head->backedge_copy_count() != 0)
  2197       continue;
  2199     // Don't clone head of OSR loop to get correct types in start block.
  2200     if (is_osr_flow() && head->start() == start_bci())
  2201       continue;
  2203     // check _no_ shared head below us
  2204     Loop* ch;
  2205     for (ch = lp->child(); ch != NULL && ch->head() != head; ch = ch->sibling());
  2206     if (ch != NULL)
  2207       continue;
  2209     // Clone head
  2210     Block* new_head = head->looping_succ(lp);
  2211     Block* clone = clone_loop_head(lp, temp_vector, temp_set);
  2212     // Update lp's info
  2213     clone->set_loop(lp);
  2214     lp->set_head(new_head);
  2215     lp->set_tail(clone);
  2216     // And move original head into outer loop
  2217     head->set_loop(lp->parent());
  2219     rslt = true;
  2221   return rslt;
  2224 // ------------------------------------------------------------------
  2225 // ciTypeFlow::clone_loop_head
  2226 //
  2227 // Clone lp's head and replace tail's successors with clone.
  2228 //
  2229 //  |
  2230 //  v
  2231 // head <-> body
  2232 //  |
  2233 //  v
  2234 // exit
  2235 //
  2236 // new_head
  2237 //
  2238 //  |
  2239 //  v
  2240 // head ----------\
  2241 //  |             |
  2242 //  |             v
  2243 //  |  clone <-> body
  2244 //  |    |
  2245 //  | /--/
  2246 //  | |
  2247 //  v v
  2248 // exit
  2249 //
  2250 ciTypeFlow::Block* ciTypeFlow::clone_loop_head(Loop* lp, StateVector* temp_vector, JsrSet* temp_set) {
  2251   Block* head = lp->head();
  2252   Block* tail = lp->tail();
  2253   if (CITraceTypeFlow) {
  2254     tty->print(">> Requesting clone of loop head "); head->print_value_on(tty);
  2255     tty->print("  for predecessor ");                tail->print_value_on(tty);
  2256     tty->cr();
  2258   Block* clone = block_at(head->start(), head->jsrs(), create_backedge_copy);
  2259   assert(clone->backedge_copy_count() == 1, "one backedge copy for all back edges");
  2261   assert(!clone->has_pre_order(), "just created");
  2262   clone->set_next_pre_order();
  2264   // Insert clone after (orig) tail in reverse post order
  2265   clone->set_rpo_next(tail->rpo_next());
  2266   tail->set_rpo_next(clone);
  2268   // tail->head becomes tail->clone
  2269   for (SuccIter iter(tail); !iter.done(); iter.next()) {
  2270     if (iter.succ() == head) {
  2271       iter.set_succ(clone);
  2274   flow_block(tail, temp_vector, temp_set);
  2275   if (head == tail) {
  2276     // For self-loops, clone->head becomes clone->clone
  2277     flow_block(clone, temp_vector, temp_set);
  2278     for (SuccIter iter(clone); !iter.done(); iter.next()) {
  2279       if (iter.succ() == head) {
  2280         iter.set_succ(clone);
  2281         break;
  2285   flow_block(clone, temp_vector, temp_set);
  2287   return clone;
  2290 // ------------------------------------------------------------------
  2291 // ciTypeFlow::flow_block
  2292 //
  2293 // Interpret the effects of the bytecodes on the incoming state
  2294 // vector of a basic block.  Push the changed state to succeeding
  2295 // basic blocks.
  2296 void ciTypeFlow::flow_block(ciTypeFlow::Block* block,
  2297                             ciTypeFlow::StateVector* state,
  2298                             ciTypeFlow::JsrSet* jsrs) {
  2299   if (CITraceTypeFlow) {
  2300     tty->print("\n>> ANALYZING BLOCK : ");
  2301     tty->cr();
  2302     block->print_on(tty);
  2304   assert(block->has_pre_order(), "pre-order is assigned before 1st flow");
  2306   int start = block->start();
  2307   int limit = block->limit();
  2308   int control = block->control();
  2309   if (control != ciBlock::fall_through_bci) {
  2310     limit = control;
  2313   // Grab the state from the current block.
  2314   block->copy_state_into(state);
  2315   state->def_locals()->clear();
  2317   GrowableArray<Block*>*           exceptions = block->exceptions();
  2318   GrowableArray<ciInstanceKlass*>* exc_klasses = block->exc_klasses();
  2319   bool has_exceptions = exceptions->length() > 0;
  2321   bool exceptions_used = false;
  2323   ciBytecodeStream str(method());
  2324   str.reset_to_bci(start);
  2325   Bytecodes::Code code;
  2326   while ((code = str.next()) != ciBytecodeStream::EOBC() &&
  2327          str.cur_bci() < limit) {
  2328     // Check for exceptional control flow from this point.
  2329     if (has_exceptions && can_trap(str)) {
  2330       flow_exceptions(exceptions, exc_klasses, state);
  2331       exceptions_used = true;
  2333     // Apply the effects of the current bytecode to our state.
  2334     bool res = state->apply_one_bytecode(&str);
  2336     // Watch for bailouts.
  2337     if (failing())  return;
  2339     if (str.cur_bc() == Bytecodes::_monitorenter) {
  2340       block->set_has_monitorenter();
  2343     if (res) {
  2345       // We have encountered a trap.  Record it in this block.
  2346       block->set_trap(state->trap_bci(), state->trap_index());
  2348       if (CITraceTypeFlow) {
  2349         tty->print_cr(">> Found trap");
  2350         block->print_on(tty);
  2353       // Save set of locals defined in this block
  2354       block->def_locals()->add(state->def_locals());
  2356       // Record (no) successors.
  2357       block->successors(&str, state, jsrs);
  2359       assert(!has_exceptions || exceptions_used, "Not removing exceptions");
  2361       // Discontinue interpretation of this Block.
  2362       return;
  2366   GrowableArray<Block*>* successors = NULL;
  2367   if (control != ciBlock::fall_through_bci) {
  2368     // Check for exceptional control flow from this point.
  2369     if (has_exceptions && can_trap(str)) {
  2370       flow_exceptions(exceptions, exc_klasses, state);
  2371       exceptions_used = true;
  2374     // Fix the JsrSet to reflect effect of the bytecode.
  2375     block->copy_jsrs_into(jsrs);
  2376     jsrs->apply_control(this, &str, state);
  2378     // Find successor edges based on old state and new JsrSet.
  2379     successors = block->successors(&str, state, jsrs);
  2381     // Apply the control changes to the state.
  2382     state->apply_one_bytecode(&str);
  2383   } else {
  2384     // Fall through control
  2385     successors = block->successors(&str, NULL, NULL);
  2388   // Save set of locals defined in this block
  2389   block->def_locals()->add(state->def_locals());
  2391   // Remove untaken exception paths
  2392   if (!exceptions_used)
  2393     exceptions->clear();
  2395   // Pass our state to successors.
  2396   flow_successors(successors, state);
  2399 // ------------------------------------------------------------------
  2400 // ciTypeFlow::PostOrderLoops::next
  2401 //
  2402 // Advance to next loop tree using a postorder, left-to-right traversal.
  2403 void ciTypeFlow::PostorderLoops::next() {
  2404   assert(!done(), "must not be done.");
  2405   if (_current->sibling() != NULL) {
  2406     _current = _current->sibling();
  2407     while (_current->child() != NULL) {
  2408       _current = _current->child();
  2410   } else {
  2411     _current = _current->parent();
  2415 // ------------------------------------------------------------------
  2416 // ciTypeFlow::PreOrderLoops::next
  2417 //
  2418 // Advance to next loop tree using a preorder, left-to-right traversal.
  2419 void ciTypeFlow::PreorderLoops::next() {
  2420   assert(!done(), "must not be done.");
  2421   if (_current->child() != NULL) {
  2422     _current = _current->child();
  2423   } else if (_current->sibling() != NULL) {
  2424     _current = _current->sibling();
  2425   } else {
  2426     while (_current != _root && _current->sibling() == NULL) {
  2427       _current = _current->parent();
  2429     if (_current == _root) {
  2430       _current = NULL;
  2431       assert(done(), "must be done.");
  2432     } else {
  2433       assert(_current->sibling() != NULL, "must be more to do");
  2434       _current = _current->sibling();
  2439 // ------------------------------------------------------------------
  2440 // ciTypeFlow::Loop::sorted_merge
  2441 //
  2442 // Merge the branch lp into this branch, sorting on the loop head
  2443 // pre_orders. Returns the leaf of the merged branch.
  2444 // Child and sibling pointers will be setup later.
  2445 // Sort is (looking from leaf towards the root)
  2446 //  descending on primary key: loop head's pre_order, and
  2447 //  ascending  on secondary key: loop tail's pre_order.
  2448 ciTypeFlow::Loop* ciTypeFlow::Loop::sorted_merge(Loop* lp) {
  2449   Loop* leaf = this;
  2450   Loop* prev = NULL;
  2451   Loop* current = leaf;
  2452   while (lp != NULL) {
  2453     int lp_pre_order = lp->head()->pre_order();
  2454     // Find insertion point for "lp"
  2455     while (current != NULL) {
  2456       if (current == lp)
  2457         return leaf; // Already in list
  2458       if (current->head()->pre_order() < lp_pre_order)
  2459         break;
  2460       if (current->head()->pre_order() == lp_pre_order &&
  2461           current->tail()->pre_order() > lp->tail()->pre_order()) {
  2462         break;
  2464       prev = current;
  2465       current = current->parent();
  2467     Loop* next_lp = lp->parent(); // Save future list of items to insert
  2468     // Insert lp before current
  2469     lp->set_parent(current);
  2470     if (prev != NULL) {
  2471       prev->set_parent(lp);
  2472     } else {
  2473       leaf = lp;
  2475     prev = lp;     // Inserted item is new prev[ious]
  2476     lp = next_lp;  // Next item to insert
  2478   return leaf;
  2481 // ------------------------------------------------------------------
  2482 // ciTypeFlow::build_loop_tree
  2483 //
  2484 // Incrementally build loop tree.
  2485 void ciTypeFlow::build_loop_tree(Block* blk) {
  2486   assert(!blk->is_post_visited(), "precondition");
  2487   Loop* innermost = NULL; // merge of loop tree branches over all successors
  2489   for (SuccIter iter(blk); !iter.done(); iter.next()) {
  2490     Loop*  lp   = NULL;
  2491     Block* succ = iter.succ();
  2492     if (!succ->is_post_visited()) {
  2493       // Found backedge since predecessor post visited, but successor is not
  2494       assert(succ->pre_order() <= blk->pre_order(), "should be backedge");
  2496       // Create a LoopNode to mark this loop.
  2497       lp = new (arena()) Loop(succ, blk);
  2498       if (succ->loop() == NULL)
  2499         succ->set_loop(lp);
  2500       // succ->loop will be updated to innermost loop on a later call, when blk==succ
  2502     } else {  // Nested loop
  2503       lp = succ->loop();
  2505       // If succ is loop head, find outer loop.
  2506       while (lp != NULL && lp->head() == succ) {
  2507         lp = lp->parent();
  2509       if (lp == NULL) {
  2510         // Infinite loop, it's parent is the root
  2511         lp = loop_tree_root();
  2515     // Check for irreducible loop.
  2516     // Successor has already been visited. If the successor's loop head
  2517     // has already been post-visited, then this is another entry into the loop.
  2518     while (lp->head()->is_post_visited() && lp != loop_tree_root()) {
  2519       _has_irreducible_entry = true;
  2520       lp->set_irreducible(succ);
  2521       if (!succ->is_on_work_list()) {
  2522         // Assume irreducible entries need more data flow
  2523         add_to_work_list(succ);
  2525       Loop* plp = lp->parent();
  2526       if (plp == NULL) {
  2527         // This only happens for some irreducible cases.  The parent
  2528         // will be updated during a later pass.
  2529         break;
  2531       lp = plp;
  2534     // Merge loop tree branch for all successors.
  2535     innermost = innermost == NULL ? lp : innermost->sorted_merge(lp);
  2537   } // end loop
  2539   if (innermost == NULL) {
  2540     assert(blk->successors()->length() == 0, "CFG exit");
  2541     blk->set_loop(loop_tree_root());
  2542   } else if (innermost->head() == blk) {
  2543     // If loop header, complete the tree pointers
  2544     if (blk->loop() != innermost) {
  2545 #ifdef ASSERT
  2546       assert(blk->loop()->head() == innermost->head(), "same head");
  2547       Loop* dl;
  2548       for (dl = innermost; dl != NULL && dl != blk->loop(); dl = dl->parent());
  2549       assert(dl == blk->loop(), "blk->loop() already in innermost list");
  2550 #endif
  2551       blk->set_loop(innermost);
  2553     innermost->def_locals()->add(blk->def_locals());
  2554     Loop* l = innermost;
  2555     Loop* p = l->parent();
  2556     while (p && l->head() == blk) {
  2557       l->set_sibling(p->child());  // Put self on parents 'next child'
  2558       p->set_child(l);             // Make self the first child of parent
  2559       p->def_locals()->add(l->def_locals());
  2560       l = p;                       // Walk up the parent chain
  2561       p = l->parent();
  2563   } else {
  2564     blk->set_loop(innermost);
  2565     innermost->def_locals()->add(blk->def_locals());
  2569 // ------------------------------------------------------------------
  2570 // ciTypeFlow::Loop::contains
  2571 //
  2572 // Returns true if lp is nested loop.
  2573 bool ciTypeFlow::Loop::contains(ciTypeFlow::Loop* lp) const {
  2574   assert(lp != NULL, "");
  2575   if (this == lp || head() == lp->head()) return true;
  2576   int depth1 = depth();
  2577   int depth2 = lp->depth();
  2578   if (depth1 > depth2)
  2579     return false;
  2580   while (depth1 < depth2) {
  2581     depth2--;
  2582     lp = lp->parent();
  2584   return this == lp;
  2587 // ------------------------------------------------------------------
  2588 // ciTypeFlow::Loop::depth
  2589 //
  2590 // Loop depth
  2591 int ciTypeFlow::Loop::depth() const {
  2592   int dp = 0;
  2593   for (Loop* lp = this->parent(); lp != NULL; lp = lp->parent())
  2594     dp++;
  2595   return dp;
  2598 #ifndef PRODUCT
  2599 // ------------------------------------------------------------------
  2600 // ciTypeFlow::Loop::print
  2601 void ciTypeFlow::Loop::print(outputStream* st, int indent) const {
  2602   for (int i = 0; i < indent; i++) st->print(" ");
  2603   st->print("%d<-%d %s",
  2604             is_root() ? 0 : this->head()->pre_order(),
  2605             is_root() ? 0 : this->tail()->pre_order(),
  2606             is_irreducible()?" irr":"");
  2607   st->print(" defs: ");
  2608   def_locals()->print_on(st, _head->outer()->method()->max_locals());
  2609   st->cr();
  2610   for (Loop* ch = child(); ch != NULL; ch = ch->sibling())
  2611     ch->print(st, indent+2);
  2613 #endif
  2615 // ------------------------------------------------------------------
  2616 // ciTypeFlow::df_flow_types
  2617 //
  2618 // Perform the depth first type flow analysis. Helper for flow_types.
  2619 void ciTypeFlow::df_flow_types(Block* start,
  2620                                bool do_flow,
  2621                                StateVector* temp_vector,
  2622                                JsrSet* temp_set) {
  2623   int dft_len = 100;
  2624   GrowableArray<Block*> stk(dft_len);
  2626   ciBlock* dummy = _methodBlocks->make_dummy_block();
  2627   JsrSet* root_set = new JsrSet(NULL, 0);
  2628   Block* root_head = new (arena()) Block(this, dummy, root_set);
  2629   Block* root_tail = new (arena()) Block(this, dummy, root_set);
  2630   root_head->set_pre_order(0);
  2631   root_head->set_post_order(0);
  2632   root_tail->set_pre_order(max_jint);
  2633   root_tail->set_post_order(max_jint);
  2634   set_loop_tree_root(new (arena()) Loop(root_head, root_tail));
  2636   stk.push(start);
  2638   _next_pre_order = 0;  // initialize pre_order counter
  2639   _rpo_list = NULL;
  2640   int next_po = 0;      // initialize post_order counter
  2642   // Compute RPO and the control flow graph
  2643   int size;
  2644   while ((size = stk.length()) > 0) {
  2645     Block* blk = stk.top(); // Leave node on stack
  2646     if (!blk->is_visited()) {
  2647       // forward arc in graph
  2648       assert (!blk->has_pre_order(), "");
  2649       blk->set_next_pre_order();
  2651       if (_next_pre_order >= (int)Compile::current()->max_node_limit() / 2) {
  2652         // Too many basic blocks.  Bail out.
  2653         // This can happen when try/finally constructs are nested to depth N,
  2654         // and there is O(2**N) cloning of jsr bodies.  See bug 4697245!
  2655         // "MaxNodeLimit / 2" is used because probably the parser will
  2656         // generate at least twice that many nodes and bail out.
  2657         record_failure("too many basic blocks");
  2658         return;
  2660       if (do_flow) {
  2661         flow_block(blk, temp_vector, temp_set);
  2662         if (failing()) return; // Watch for bailouts.
  2664     } else if (!blk->is_post_visited()) {
  2665       // cross or back arc
  2666       for (SuccIter iter(blk); !iter.done(); iter.next()) {
  2667         Block* succ = iter.succ();
  2668         if (!succ->is_visited()) {
  2669           stk.push(succ);
  2672       if (stk.length() == size) {
  2673         // There were no additional children, post visit node now
  2674         stk.pop(); // Remove node from stack
  2676         build_loop_tree(blk);
  2677         blk->set_post_order(next_po++);   // Assign post order
  2678         prepend_to_rpo_list(blk);
  2679         assert(blk->is_post_visited(), "");
  2681         if (blk->is_loop_head() && !blk->is_on_work_list()) {
  2682           // Assume loop heads need more data flow
  2683           add_to_work_list(blk);
  2686     } else {
  2687       stk.pop(); // Remove post-visited node from stack
  2692 // ------------------------------------------------------------------
  2693 // ciTypeFlow::flow_types
  2694 //
  2695 // Perform the type flow analysis, creating and cloning Blocks as
  2696 // necessary.
  2697 void ciTypeFlow::flow_types() {
  2698   ResourceMark rm;
  2699   StateVector* temp_vector = new StateVector(this);
  2700   JsrSet* temp_set = new JsrSet(NULL, 16);
  2702   // Create the method entry block.
  2703   Block* start = block_at(start_bci(), temp_set);
  2705   // Load the initial state into it.
  2706   const StateVector* start_state = get_start_state();
  2707   if (failing())  return;
  2708   start->meet(start_state);
  2710   // Depth first visit
  2711   df_flow_types(start, true /*do flow*/, temp_vector, temp_set);
  2713   if (failing())  return;
  2714   assert(_rpo_list == start, "must be start");
  2716   // Any loops found?
  2717   if (loop_tree_root()->child() != NULL &&
  2718       env()->comp_level() >= CompLevel_full_optimization) {
  2719       // Loop optimizations are not performed on Tier1 compiles.
  2721     bool changed = clone_loop_heads(loop_tree_root(), temp_vector, temp_set);
  2723     // If some loop heads were cloned, recompute postorder and loop tree
  2724     if (changed) {
  2725       loop_tree_root()->set_child(NULL);
  2726       for (Block* blk = _rpo_list; blk != NULL;) {
  2727         Block* next = blk->rpo_next();
  2728         blk->df_init();
  2729         blk = next;
  2731       df_flow_types(start, false /*no flow*/, temp_vector, temp_set);
  2735   if (CITraceTypeFlow) {
  2736     tty->print_cr("\nLoop tree");
  2737     loop_tree_root()->print();
  2740   // Continue flow analysis until fixed point reached
  2742   debug_only(int max_block = _next_pre_order;)
  2744   while (!work_list_empty()) {
  2745     Block* blk = work_list_next();
  2746     assert (blk->has_post_order(), "post order assigned above");
  2748     flow_block(blk, temp_vector, temp_set);
  2750     assert (max_block == _next_pre_order, "no new blocks");
  2751     assert (!failing(), "no more bailouts");
  2755 // ------------------------------------------------------------------
  2756 // ciTypeFlow::map_blocks
  2757 //
  2758 // Create the block map, which indexes blocks in reverse post-order.
  2759 void ciTypeFlow::map_blocks() {
  2760   assert(_block_map == NULL, "single initialization");
  2761   int block_ct = _next_pre_order;
  2762   _block_map = NEW_ARENA_ARRAY(arena(), Block*, block_ct);
  2763   assert(block_ct == block_count(), "");
  2765   Block* blk = _rpo_list;
  2766   for (int m = 0; m < block_ct; m++) {
  2767     int rpo = blk->rpo();
  2768     assert(rpo == m, "should be sequential");
  2769     _block_map[rpo] = blk;
  2770     blk = blk->rpo_next();
  2772   assert(blk == NULL, "should be done");
  2774   for (int j = 0; j < block_ct; j++) {
  2775     assert(_block_map[j] != NULL, "must not drop any blocks");
  2776     Block* block = _block_map[j];
  2777     // Remove dead blocks from successor lists:
  2778     for (int e = 0; e <= 1; e++) {
  2779       GrowableArray<Block*>* l = e? block->exceptions(): block->successors();
  2780       for (int k = 0; k < l->length(); k++) {
  2781         Block* s = l->at(k);
  2782         if (!s->has_post_order()) {
  2783           if (CITraceTypeFlow) {
  2784             tty->print("Removing dead %s successor of #%d: ", (e? "exceptional":  "normal"), block->pre_order());
  2785             s->print_value_on(tty);
  2786             tty->cr();
  2788           l->remove(s);
  2789           --k;
  2796 // ------------------------------------------------------------------
  2797 // ciTypeFlow::get_block_for
  2798 //
  2799 // Find a block with this ciBlock which has a compatible JsrSet.
  2800 // If no such block exists, create it, unless the option is no_create.
  2801 // If the option is create_backedge_copy, always create a fresh backedge copy.
  2802 ciTypeFlow::Block* ciTypeFlow::get_block_for(int ciBlockIndex, ciTypeFlow::JsrSet* jsrs, CreateOption option) {
  2803   Arena* a = arena();
  2804   GrowableArray<Block*>* blocks = _idx_to_blocklist[ciBlockIndex];
  2805   if (blocks == NULL) {
  2806     // Query only?
  2807     if (option == no_create)  return NULL;
  2809     // Allocate the growable array.
  2810     blocks = new (a) GrowableArray<Block*>(a, 4, 0, NULL);
  2811     _idx_to_blocklist[ciBlockIndex] = blocks;
  2814   if (option != create_backedge_copy) {
  2815     int len = blocks->length();
  2816     for (int i = 0; i < len; i++) {
  2817       Block* block = blocks->at(i);
  2818       if (!block->is_backedge_copy() && block->is_compatible_with(jsrs)) {
  2819         return block;
  2824   // Query only?
  2825   if (option == no_create)  return NULL;
  2827   // We did not find a compatible block.  Create one.
  2828   Block* new_block = new (a) Block(this, _methodBlocks->block(ciBlockIndex), jsrs);
  2829   if (option == create_backedge_copy)  new_block->set_backedge_copy(true);
  2830   blocks->append(new_block);
  2831   return new_block;
  2834 // ------------------------------------------------------------------
  2835 // ciTypeFlow::backedge_copy_count
  2836 //
  2837 int ciTypeFlow::backedge_copy_count(int ciBlockIndex, ciTypeFlow::JsrSet* jsrs) const {
  2838   GrowableArray<Block*>* blocks = _idx_to_blocklist[ciBlockIndex];
  2840   if (blocks == NULL) {
  2841     return 0;
  2844   int count = 0;
  2845   int len = blocks->length();
  2846   for (int i = 0; i < len; i++) {
  2847     Block* block = blocks->at(i);
  2848     if (block->is_backedge_copy() && block->is_compatible_with(jsrs)) {
  2849       count++;
  2853   return count;
  2856 // ------------------------------------------------------------------
  2857 // ciTypeFlow::do_flow
  2858 //
  2859 // Perform type inference flow analysis.
  2860 void ciTypeFlow::do_flow() {
  2861   if (CITraceTypeFlow) {
  2862     tty->print_cr("\nPerforming flow analysis on method");
  2863     method()->print();
  2864     if (is_osr_flow())  tty->print(" at OSR bci %d", start_bci());
  2865     tty->cr();
  2866     method()->print_codes();
  2868   if (CITraceTypeFlow) {
  2869     tty->print_cr("Initial CI Blocks");
  2870     print_on(tty);
  2872   flow_types();
  2873   // Watch for bailouts.
  2874   if (failing()) {
  2875     return;
  2878   map_blocks();
  2880   if (CIPrintTypeFlow || CITraceTypeFlow) {
  2881     rpo_print_on(tty);
  2885 // ------------------------------------------------------------------
  2886 // ciTypeFlow::record_failure()
  2887 // The ciTypeFlow object keeps track of failure reasons separately from the ciEnv.
  2888 // This is required because there is not a 1-1 relation between the ciEnv and
  2889 // the TypeFlow passes within a compilation task.  For example, if the compiler
  2890 // is considering inlining a method, it will request a TypeFlow.  If that fails,
  2891 // the compilation as a whole may continue without the inlining.  Some TypeFlow
  2892 // requests are not optional; if they fail the requestor is responsible for
  2893 // copying the failure reason up to the ciEnv.  (See Parse::Parse.)
  2894 void ciTypeFlow::record_failure(const char* reason) {
  2895   if (env()->log() != NULL) {
  2896     env()->log()->elem("failure reason='%s' phase='typeflow'", reason);
  2898   if (_failure_reason == NULL) {
  2899     // Record the first failure reason.
  2900     _failure_reason = reason;
  2904 #ifndef PRODUCT
  2905 // ------------------------------------------------------------------
  2906 // ciTypeFlow::print_on
  2907 void ciTypeFlow::print_on(outputStream* st) const {
  2908   // Walk through CI blocks
  2909   st->print_cr("********************************************************");
  2910   st->print   ("TypeFlow for ");
  2911   method()->name()->print_symbol_on(st);
  2912   int limit_bci = code_size();
  2913   st->print_cr("  %d bytes", limit_bci);
  2914   ciMethodBlocks  *mblks = _methodBlocks;
  2915   ciBlock* current = NULL;
  2916   for (int bci = 0; bci < limit_bci; bci++) {
  2917     ciBlock* blk = mblks->block_containing(bci);
  2918     if (blk != NULL && blk != current) {
  2919       current = blk;
  2920       current->print_on(st);
  2922       GrowableArray<Block*>* blocks = _idx_to_blocklist[blk->index()];
  2923       int num_blocks = (blocks == NULL) ? 0 : blocks->length();
  2925       if (num_blocks == 0) {
  2926         st->print_cr("  No Blocks");
  2927       } else {
  2928         for (int i = 0; i < num_blocks; i++) {
  2929           Block* block = blocks->at(i);
  2930           block->print_on(st);
  2933       st->print_cr("--------------------------------------------------------");
  2934       st->cr();
  2937   st->print_cr("********************************************************");
  2938   st->cr();
  2941 void ciTypeFlow::rpo_print_on(outputStream* st) const {
  2942   st->print_cr("********************************************************");
  2943   st->print   ("TypeFlow for ");
  2944   method()->name()->print_symbol_on(st);
  2945   int limit_bci = code_size();
  2946   st->print_cr("  %d bytes", limit_bci);
  2947   for (Block* blk = _rpo_list; blk != NULL; blk = blk->rpo_next()) {
  2948     blk->print_on(st);
  2949     st->print_cr("--------------------------------------------------------");
  2950     st->cr();
  2952   st->print_cr("********************************************************");
  2953   st->cr();
  2955 #endif

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