aoqi@0: /*
aoqi@0:  * Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  *
aoqi@0:  */
aoqi@0: 
aoqi@0: #include "precompiled.hpp"
aoqi@0: #include "ci/ciConstant.hpp"
aoqi@0: #include "ci/ciField.hpp"
aoqi@0: #include "ci/ciMethod.hpp"
aoqi@0: #include "ci/ciMethodData.hpp"
aoqi@0: #include "ci/ciObjArrayKlass.hpp"
aoqi@0: #include "ci/ciStreams.hpp"
aoqi@0: #include "ci/ciTypeArrayKlass.hpp"
aoqi@0: #include "ci/ciTypeFlow.hpp"
aoqi@0: #include "compiler/compileLog.hpp"
aoqi@0: #include "interpreter/bytecode.hpp"
aoqi@0: #include "interpreter/bytecodes.hpp"
aoqi@0: #include "memory/allocation.inline.hpp"
vlivanov@7385: #include "opto/compile.hpp"
goetz@7546: #include "opto/node.hpp"
aoqi@0: #include "runtime/deoptimization.hpp"
aoqi@0: #include "utilities/growableArray.hpp"
aoqi@0: 
aoqi@0: // ciTypeFlow::JsrSet
aoqi@0: //
aoqi@0: // A JsrSet represents some set of JsrRecords.  This class
aoqi@0: // is used to record a set of all jsr routines which we permit
aoqi@0: // execution to return (ret) from.
aoqi@0: //
aoqi@0: // During abstract interpretation, JsrSets are used to determine
aoqi@0: // whether two paths which reach a given block are unique, and
aoqi@0: // should be cloned apart, or are compatible, and should merge
aoqi@0: // together.
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::JsrSet::JsrSet
aoqi@0: ciTypeFlow::JsrSet::JsrSet(Arena* arena, int default_len) {
aoqi@0:   if (arena != NULL) {
aoqi@0:     // Allocate growable array in Arena.
aoqi@0:     _set = new (arena) GrowableArray<JsrRecord*>(arena, default_len, 0, NULL);
aoqi@0:   } else {
aoqi@0:     // Allocate growable array in current ResourceArea.
aoqi@0:     _set = new GrowableArray<JsrRecord*>(4, 0, NULL, false);
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::JsrSet::copy_into
aoqi@0: void ciTypeFlow::JsrSet::copy_into(JsrSet* jsrs) {
aoqi@0:   int len = size();
aoqi@0:   jsrs->_set->clear();
aoqi@0:   for (int i = 0; i < len; i++) {
aoqi@0:     jsrs->_set->append(_set->at(i));
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::JsrSet::is_compatible_with
aoqi@0: //
aoqi@0: // !!!! MISGIVINGS ABOUT THIS... disregard
aoqi@0: //
aoqi@0: // Is this JsrSet compatible with some other JsrSet?
aoqi@0: //
aoqi@0: // In set-theoretic terms, a JsrSet can be viewed as a partial function
aoqi@0: // from entry addresses to return addresses.  Two JsrSets A and B are
aoqi@0: // compatible iff
aoqi@0: //
aoqi@0: //   For any x,
aoqi@0: //   A(x) defined and B(x) defined implies A(x) == B(x)
aoqi@0: //
aoqi@0: // Less formally, two JsrSets are compatible when they have identical
aoqi@0: // return addresses for any entry addresses they share in common.
aoqi@0: bool ciTypeFlow::JsrSet::is_compatible_with(JsrSet* other) {
aoqi@0:   // Walk through both sets in parallel.  If the same entry address
aoqi@0:   // appears in both sets, then the return address must match for
aoqi@0:   // the sets to be compatible.
aoqi@0:   int size1 = size();
aoqi@0:   int size2 = other->size();
aoqi@0: 
aoqi@0:   // Special case.  If nothing is on the jsr stack, then there can
aoqi@0:   // be no ret.
aoqi@0:   if (size2 == 0) {
aoqi@0:     return true;
aoqi@0:   } else if (size1 != size2) {
aoqi@0:     return false;
aoqi@0:   } else {
aoqi@0:     for (int i = 0; i < size1; i++) {
aoqi@0:       JsrRecord* record1 = record_at(i);
aoqi@0:       JsrRecord* record2 = other->record_at(i);
aoqi@0:       if (record1->entry_address() != record2->entry_address() ||
aoqi@0:           record1->return_address() != record2->return_address()) {
aoqi@0:         return false;
aoqi@0:       }
aoqi@0:     }
aoqi@0:     return true;
aoqi@0:   }
aoqi@0: 
aoqi@0: #if 0
aoqi@0:   int pos1 = 0;
aoqi@0:   int pos2 = 0;
aoqi@0:   int size1 = size();
aoqi@0:   int size2 = other->size();
aoqi@0:   while (pos1 < size1 && pos2 < size2) {
aoqi@0:     JsrRecord* record1 = record_at(pos1);
aoqi@0:     JsrRecord* record2 = other->record_at(pos2);
aoqi@0:     int entry1 = record1->entry_address();
aoqi@0:     int entry2 = record2->entry_address();
aoqi@0:     if (entry1 < entry2) {
aoqi@0:       pos1++;
aoqi@0:     } else if (entry1 > entry2) {
aoqi@0:       pos2++;
aoqi@0:     } else {
aoqi@0:       if (record1->return_address() == record2->return_address()) {
aoqi@0:         pos1++;
aoqi@0:         pos2++;
aoqi@0:       } else {
aoqi@0:         // These two JsrSets are incompatible.
aoqi@0:         return false;
aoqi@0:       }
aoqi@0:     }
aoqi@0:   }
aoqi@0:   // The two JsrSets agree.
aoqi@0:   return true;
aoqi@0: #endif
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::JsrSet::insert_jsr_record
aoqi@0: //
aoqi@0: // Insert the given JsrRecord into the JsrSet, maintaining the order
aoqi@0: // of the set and replacing any element with the same entry address.
aoqi@0: void ciTypeFlow::JsrSet::insert_jsr_record(JsrRecord* record) {
aoqi@0:   int len = size();
aoqi@0:   int entry = record->entry_address();
aoqi@0:   int pos = 0;
aoqi@0:   for ( ; pos < len; pos++) {
aoqi@0:     JsrRecord* current = record_at(pos);
aoqi@0:     if (entry == current->entry_address()) {
aoqi@0:       // Stomp over this entry.
aoqi@0:       _set->at_put(pos, record);
aoqi@0:       assert(size() == len, "must be same size");
aoqi@0:       return;
aoqi@0:     } else if (entry < current->entry_address()) {
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Insert the record into the list.
aoqi@0:   JsrRecord* swap = record;
aoqi@0:   JsrRecord* temp = NULL;
aoqi@0:   for ( ; pos < len; pos++) {
aoqi@0:     temp = _set->at(pos);
aoqi@0:     _set->at_put(pos, swap);
aoqi@0:     swap = temp;
aoqi@0:   }
aoqi@0:   _set->append(swap);
aoqi@0:   assert(size() == len+1, "must be larger");
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::JsrSet::remove_jsr_record
aoqi@0: //
aoqi@0: // Remove the JsrRecord with the given return address from the JsrSet.
aoqi@0: void ciTypeFlow::JsrSet::remove_jsr_record(int return_address) {
aoqi@0:   int len = size();
aoqi@0:   for (int i = 0; i < len; i++) {
aoqi@0:     if (record_at(i)->return_address() == return_address) {
aoqi@0:       // We have found the proper entry.  Remove it from the
aoqi@0:       // JsrSet and exit.
aoqi@0:       for (int j = i+1; j < len ; j++) {
aoqi@0:         _set->at_put(j-1, _set->at(j));
aoqi@0:       }
aoqi@0:       _set->trunc_to(len-1);
aoqi@0:       assert(size() == len-1, "must be smaller");
aoqi@0:       return;
aoqi@0:     }
aoqi@0:   }
aoqi@0:   assert(false, "verify: returning from invalid subroutine");
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::JsrSet::apply_control
aoqi@0: //
aoqi@0: // Apply the effect of a control-flow bytecode on the JsrSet.  The
aoqi@0: // only bytecodes that modify the JsrSet are jsr and ret.
aoqi@0: void ciTypeFlow::JsrSet::apply_control(ciTypeFlow* analyzer,
aoqi@0:                                        ciBytecodeStream* str,
aoqi@0:                                        ciTypeFlow::StateVector* state) {
aoqi@0:   Bytecodes::Code code = str->cur_bc();
aoqi@0:   if (code == Bytecodes::_jsr) {
aoqi@0:     JsrRecord* record =
aoqi@0:       analyzer->make_jsr_record(str->get_dest(), str->next_bci());
aoqi@0:     insert_jsr_record(record);
aoqi@0:   } else if (code == Bytecodes::_jsr_w) {
aoqi@0:     JsrRecord* record =
aoqi@0:       analyzer->make_jsr_record(str->get_far_dest(), str->next_bci());
aoqi@0:     insert_jsr_record(record);
aoqi@0:   } else if (code == Bytecodes::_ret) {
aoqi@0:     Cell local = state->local(str->get_index());
aoqi@0:     ciType* return_address = state->type_at(local);
aoqi@0:     assert(return_address->is_return_address(), "verify: wrong type");
aoqi@0:     if (size() == 0) {
aoqi@0:       // Ret-state underflow:  Hit a ret w/o any previous jsrs.  Bail out.
aoqi@0:       // This can happen when a loop is inside a finally clause (4614060).
aoqi@0:       analyzer->record_failure("OSR in finally clause");
aoqi@0:       return;
aoqi@0:     }
aoqi@0:     remove_jsr_record(return_address->as_return_address()->bci());
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: #ifndef PRODUCT
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::JsrSet::print_on
aoqi@0: void ciTypeFlow::JsrSet::print_on(outputStream* st) const {
aoqi@0:   st->print("{ ");
aoqi@0:   int num_elements = size();
aoqi@0:   if (num_elements > 0) {
aoqi@0:     int i = 0;
aoqi@0:     for( ; i < num_elements - 1; i++) {
aoqi@0:       _set->at(i)->print_on(st);
aoqi@0:       st->print(", ");
aoqi@0:     }
aoqi@0:     _set->at(i)->print_on(st);
aoqi@0:     st->print(" ");
aoqi@0:   }
aoqi@0:   st->print("}");
aoqi@0: }
aoqi@0: #endif
aoqi@0: 
aoqi@0: // ciTypeFlow::StateVector
aoqi@0: //
aoqi@0: // A StateVector summarizes the type information at some point in
aoqi@0: // the program.
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::type_meet
aoqi@0: //
aoqi@0: // Meet two types.
aoqi@0: //
aoqi@0: // The semi-lattice of types use by this analysis are modeled on those
aoqi@0: // of the verifier.  The lattice is as follows:
aoqi@0: //
aoqi@0: //        top_type() >= all non-extremal types >= bottom_type
aoqi@0: //                             and
aoqi@0: //   Every primitive type is comparable only with itself.  The meet of
aoqi@0: //   reference types is determined by their kind: instance class,
aoqi@0: //   interface, or array class.  The meet of two types of the same
aoqi@0: //   kind is their least common ancestor.  The meet of two types of
aoqi@0: //   different kinds is always java.lang.Object.
aoqi@0: ciType* ciTypeFlow::StateVector::type_meet_internal(ciType* t1, ciType* t2, ciTypeFlow* analyzer) {
aoqi@0:   assert(t1 != t2, "checked in caller");
aoqi@0:   if (t1->equals(top_type())) {
aoqi@0:     return t2;
aoqi@0:   } else if (t2->equals(top_type())) {
aoqi@0:     return t1;
aoqi@0:   } else if (t1->is_primitive_type() || t2->is_primitive_type()) {
aoqi@0:     // Special case null_type.  null_type meet any reference type T
aoqi@0:     // is T.  null_type meet null_type is null_type.
aoqi@0:     if (t1->equals(null_type())) {
aoqi@0:       if (!t2->is_primitive_type() || t2->equals(null_type())) {
aoqi@0:         return t2;
aoqi@0:       }
aoqi@0:     } else if (t2->equals(null_type())) {
aoqi@0:       if (!t1->is_primitive_type()) {
aoqi@0:         return t1;
aoqi@0:       }
aoqi@0:     }
aoqi@0: 
aoqi@0:     // At least one of the two types is a non-top primitive type.
aoqi@0:     // The other type is not equal to it.  Fall to bottom.
aoqi@0:     return bottom_type();
aoqi@0:   } else {
aoqi@0:     // Both types are non-top non-primitive types.  That is,
aoqi@0:     // both types are either instanceKlasses or arrayKlasses.
aoqi@0:     ciKlass* object_klass = analyzer->env()->Object_klass();
aoqi@0:     ciKlass* k1 = t1->as_klass();
aoqi@0:     ciKlass* k2 = t2->as_klass();
aoqi@0:     if (k1->equals(object_klass) || k2->equals(object_klass)) {
aoqi@0:       return object_klass;
aoqi@0:     } else if (!k1->is_loaded() || !k2->is_loaded()) {
aoqi@0:       // Unloaded classes fall to java.lang.Object at a merge.
aoqi@0:       return object_klass;
aoqi@0:     } else if (k1->is_interface() != k2->is_interface()) {
aoqi@0:       // When an interface meets a non-interface, we get Object;
aoqi@0:       // This is what the verifier does.
aoqi@0:       return object_klass;
aoqi@0:     } else if (k1->is_array_klass() || k2->is_array_klass()) {
aoqi@0:       // When an array meets a non-array, we get Object.
aoqi@0:       // When objArray meets typeArray, we also get Object.
aoqi@0:       // And when typeArray meets different typeArray, we again get Object.
aoqi@0:       // But when objArray meets objArray, we look carefully at element types.
aoqi@0:       if (k1->is_obj_array_klass() && k2->is_obj_array_klass()) {
aoqi@0:         // Meet the element types, then construct the corresponding array type.
aoqi@0:         ciKlass* elem1 = k1->as_obj_array_klass()->element_klass();
aoqi@0:         ciKlass* elem2 = k2->as_obj_array_klass()->element_klass();
aoqi@0:         ciKlass* elem  = type_meet_internal(elem1, elem2, analyzer)->as_klass();
aoqi@0:         // Do an easy shortcut if one type is a super of the other.
aoqi@0:         if (elem == elem1) {
aoqi@0:           assert(k1 == ciObjArrayKlass::make(elem), "shortcut is OK");
aoqi@0:           return k1;
aoqi@0:         } else if (elem == elem2) {
aoqi@0:           assert(k2 == ciObjArrayKlass::make(elem), "shortcut is OK");
aoqi@0:           return k2;
aoqi@0:         } else {
aoqi@0:           return ciObjArrayKlass::make(elem);
aoqi@0:         }
aoqi@0:       } else {
aoqi@0:         return object_klass;
aoqi@0:       }
aoqi@0:     } else {
aoqi@0:       // Must be two plain old instance klasses.
aoqi@0:       assert(k1->is_instance_klass(), "previous cases handle non-instances");
aoqi@0:       assert(k2->is_instance_klass(), "previous cases handle non-instances");
aoqi@0:       return k1->least_common_ancestor(k2);
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::StateVector
aoqi@0: //
aoqi@0: // Build a new state vector
aoqi@0: ciTypeFlow::StateVector::StateVector(ciTypeFlow* analyzer) {
aoqi@0:   _outer = analyzer;
aoqi@0:   _stack_size = -1;
aoqi@0:   _monitor_count = -1;
aoqi@0:   // Allocate the _types array
aoqi@0:   int max_cells = analyzer->max_cells();
aoqi@0:   _types = (ciType**)analyzer->arena()->Amalloc(sizeof(ciType*) * max_cells);
aoqi@0:   for (int i=0; i<max_cells; i++) {
aoqi@0:     _types[i] = top_type();
aoqi@0:   }
aoqi@0:   _trap_bci = -1;
aoqi@0:   _trap_index = 0;
aoqi@0:   _def_locals.clear();
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::get_start_state
aoqi@0: //
aoqi@0: // Set this vector to the method entry state.
aoqi@0: const ciTypeFlow::StateVector* ciTypeFlow::get_start_state() {
aoqi@0:   StateVector* state = new StateVector(this);
aoqi@0:   if (is_osr_flow()) {
aoqi@0:     ciTypeFlow* non_osr_flow = method()->get_flow_analysis();
aoqi@0:     if (non_osr_flow->failing()) {
aoqi@0:       record_failure(non_osr_flow->failure_reason());
aoqi@0:       return NULL;
aoqi@0:     }
aoqi@0:     JsrSet* jsrs = new JsrSet(NULL, 16);
aoqi@0:     Block* non_osr_block = non_osr_flow->existing_block_at(start_bci(), jsrs);
aoqi@0:     if (non_osr_block == NULL) {
aoqi@0:       record_failure("cannot reach OSR point");
aoqi@0:       return NULL;
aoqi@0:     }
aoqi@0:     // load up the non-OSR state at this point
aoqi@0:     non_osr_block->copy_state_into(state);
aoqi@0:     int non_osr_start = non_osr_block->start();
aoqi@0:     if (non_osr_start != start_bci()) {
aoqi@0:       // must flow forward from it
aoqi@0:       if (CITraceTypeFlow) {
aoqi@0:         tty->print_cr(">> Interpreting pre-OSR block %d:", non_osr_start);
aoqi@0:       }
aoqi@0:       Block* block = block_at(non_osr_start, jsrs);
aoqi@0:       assert(block->limit() == start_bci(), "must flow forward to start");
aoqi@0:       flow_block(block, state, jsrs);
aoqi@0:     }
aoqi@0:     return state;
aoqi@0:     // Note:  The code below would be an incorrect for an OSR flow,
aoqi@0:     // even if it were possible for an OSR entry point to be at bci zero.
aoqi@0:   }
aoqi@0:   // "Push" the method signature into the first few locals.
aoqi@0:   state->set_stack_size(-max_locals());
aoqi@0:   if (!method()->is_static()) {
aoqi@0:     state->push(method()->holder());
aoqi@0:     assert(state->tos() == state->local(0), "");
aoqi@0:   }
aoqi@0:   for (ciSignatureStream str(method()->signature());
aoqi@0:        !str.at_return_type();
aoqi@0:        str.next()) {
aoqi@0:     state->push_translate(str.type());
aoqi@0:   }
aoqi@0:   // Set the rest of the locals to bottom.
aoqi@0:   Cell cell = state->next_cell(state->tos());
aoqi@0:   state->set_stack_size(0);
aoqi@0:   int limit = state->limit_cell();
aoqi@0:   for (; cell < limit; cell = state->next_cell(cell)) {
aoqi@0:     state->set_type_at(cell, state->bottom_type());
aoqi@0:   }
aoqi@0:   // Lock an object, if necessary.
aoqi@0:   state->set_monitor_count(method()->is_synchronized() ? 1 : 0);
aoqi@0:   return state;
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::copy_into
aoqi@0: //
aoqi@0: // Copy our value into some other StateVector
aoqi@0: void ciTypeFlow::StateVector::copy_into(ciTypeFlow::StateVector* copy)
aoqi@0: const {
aoqi@0:   copy->set_stack_size(stack_size());
aoqi@0:   copy->set_monitor_count(monitor_count());
aoqi@0:   Cell limit = limit_cell();
aoqi@0:   for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
aoqi@0:     copy->set_type_at(c, type_at(c));
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::meet
aoqi@0: //
aoqi@0: // Meets this StateVector with another, destructively modifying this
aoqi@0: // one.  Returns true if any modification takes place.
aoqi@0: bool ciTypeFlow::StateVector::meet(const ciTypeFlow::StateVector* incoming) {
aoqi@0:   if (monitor_count() == -1) {
aoqi@0:     set_monitor_count(incoming->monitor_count());
aoqi@0:   }
aoqi@0:   assert(monitor_count() == incoming->monitor_count(), "monitors must match");
aoqi@0: 
aoqi@0:   if (stack_size() == -1) {
aoqi@0:     set_stack_size(incoming->stack_size());
aoqi@0:     Cell limit = limit_cell();
aoqi@0:     #ifdef ASSERT
aoqi@0:     { for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
aoqi@0:         assert(type_at(c) == top_type(), "");
aoqi@0:     } }
aoqi@0:     #endif
aoqi@0:     // Make a simple copy of the incoming state.
aoqi@0:     for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
aoqi@0:       set_type_at(c, incoming->type_at(c));
aoqi@0:     }
aoqi@0:     return true;  // it is always different the first time
aoqi@0:   }
aoqi@0: #ifdef ASSERT
aoqi@0:   if (stack_size() != incoming->stack_size()) {
aoqi@0:     _outer->method()->print_codes();
aoqi@0:     tty->print_cr("!!!! Stack size conflict");
aoqi@0:     tty->print_cr("Current state:");
aoqi@0:     print_on(tty);
aoqi@0:     tty->print_cr("Incoming state:");
aoqi@0:     ((StateVector*)incoming)->print_on(tty);
aoqi@0:   }
aoqi@0: #endif
aoqi@0:   assert(stack_size() == incoming->stack_size(), "sanity");
aoqi@0: 
aoqi@0:   bool different = false;
aoqi@0:   Cell limit = limit_cell();
aoqi@0:   for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
aoqi@0:     ciType* t1 = type_at(c);
aoqi@0:     ciType* t2 = incoming->type_at(c);
aoqi@0:     if (!t1->equals(t2)) {
aoqi@0:       ciType* new_type = type_meet(t1, t2);
aoqi@0:       if (!t1->equals(new_type)) {
aoqi@0:         set_type_at(c, new_type);
aoqi@0:         different = true;
aoqi@0:       }
aoqi@0:     }
aoqi@0:   }
aoqi@0:   return different;
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::meet_exception
aoqi@0: //
aoqi@0: // Meets this StateVector with another, destructively modifying this
aoqi@0: // one.  The incoming state is coming via an exception.  Returns true
aoqi@0: // if any modification takes place.
aoqi@0: bool ciTypeFlow::StateVector::meet_exception(ciInstanceKlass* exc,
aoqi@0:                                      const ciTypeFlow::StateVector* incoming) {
aoqi@0:   if (monitor_count() == -1) {
aoqi@0:     set_monitor_count(incoming->monitor_count());
aoqi@0:   }
aoqi@0:   assert(monitor_count() == incoming->monitor_count(), "monitors must match");
aoqi@0: 
aoqi@0:   if (stack_size() == -1) {
aoqi@0:     set_stack_size(1);
aoqi@0:   }
aoqi@0: 
aoqi@0:   assert(stack_size() ==  1, "must have one-element stack");
aoqi@0: 
aoqi@0:   bool different = false;
aoqi@0: 
aoqi@0:   // Meet locals from incoming array.
aoqi@0:   Cell limit = local(_outer->max_locals()-1);
aoqi@0:   for (Cell c = start_cell(); c <= limit; c = next_cell(c)) {
aoqi@0:     ciType* t1 = type_at(c);
aoqi@0:     ciType* t2 = incoming->type_at(c);
aoqi@0:     if (!t1->equals(t2)) {
aoqi@0:       ciType* new_type = type_meet(t1, t2);
aoqi@0:       if (!t1->equals(new_type)) {
aoqi@0:         set_type_at(c, new_type);
aoqi@0:         different = true;
aoqi@0:       }
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Handle stack separately.  When an exception occurs, the
aoqi@0:   // only stack entry is the exception instance.
aoqi@0:   ciType* tos_type = type_at_tos();
aoqi@0:   if (!tos_type->equals(exc)) {
aoqi@0:     ciType* new_type = type_meet(tos_type, exc);
aoqi@0:     if (!tos_type->equals(new_type)) {
aoqi@0:       set_type_at_tos(new_type);
aoqi@0:       different = true;
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   return different;
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::push_translate
aoqi@0: void ciTypeFlow::StateVector::push_translate(ciType* type) {
aoqi@0:   BasicType basic_type = type->basic_type();
aoqi@0:   if (basic_type == T_BOOLEAN || basic_type == T_CHAR ||
aoqi@0:       basic_type == T_BYTE    || basic_type == T_SHORT) {
aoqi@0:     push_int();
aoqi@0:   } else {
aoqi@0:     push(type);
aoqi@0:     if (type->is_two_word()) {
aoqi@0:       push(half_type(type));
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::do_aaload
aoqi@0: void ciTypeFlow::StateVector::do_aaload(ciBytecodeStream* str) {
aoqi@0:   pop_int();
aoqi@0:   ciObjArrayKlass* array_klass = pop_objArray();
aoqi@0:   if (array_klass == NULL) {
aoqi@0:     // Did aaload on a null reference; push a null and ignore the exception.
aoqi@0:     // This instruction will never continue normally.  All we have to do
aoqi@0:     // is report a value that will meet correctly with any downstream
aoqi@0:     // reference types on paths that will truly be executed.  This null type
aoqi@0:     // meets with any reference type to yield that same reference type.
aoqi@0:     // (The compiler will generate an unconditional exception here.)
aoqi@0:     push(null_type());
aoqi@0:     return;
aoqi@0:   }
aoqi@0:   if (!array_klass->is_loaded()) {
aoqi@0:     // Only fails for some -Xcomp runs
aoqi@0:     trap(str, array_klass,
aoqi@0:          Deoptimization::make_trap_request
aoqi@0:          (Deoptimization::Reason_unloaded,
aoqi@0:           Deoptimization::Action_reinterpret));
aoqi@0:     return;
aoqi@0:   }
aoqi@0:   ciKlass* element_klass = array_klass->element_klass();
aoqi@0:   if (!element_klass->is_loaded() && element_klass->is_instance_klass()) {
aoqi@0:     Untested("unloaded array element class in ciTypeFlow");
aoqi@0:     trap(str, element_klass,
aoqi@0:          Deoptimization::make_trap_request
aoqi@0:          (Deoptimization::Reason_unloaded,
aoqi@0:           Deoptimization::Action_reinterpret));
aoqi@0:   } else {
aoqi@0:     push_object(element_klass);
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::do_checkcast
aoqi@0: void ciTypeFlow::StateVector::do_checkcast(ciBytecodeStream* str) {
aoqi@0:   bool will_link;
aoqi@0:   ciKlass* klass = str->get_klass(will_link);
aoqi@0:   if (!will_link) {
aoqi@0:     // VM's interpreter will not load 'klass' if object is NULL.
aoqi@0:     // Type flow after this block may still be needed in two situations:
aoqi@0:     // 1) C2 uses do_null_assert() and continues compilation for later blocks
aoqi@0:     // 2) C2 does an OSR compile in a later block (see bug 4778368).
aoqi@0:     pop_object();
aoqi@0:     do_null_assert(klass);
aoqi@0:   } else {
aoqi@0:     pop_object();
aoqi@0:     push_object(klass);
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::do_getfield
aoqi@0: void ciTypeFlow::StateVector::do_getfield(ciBytecodeStream* str) {
aoqi@0:   // could add assert here for type of object.
aoqi@0:   pop_object();
aoqi@0:   do_getstatic(str);
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::do_getstatic
aoqi@0: void ciTypeFlow::StateVector::do_getstatic(ciBytecodeStream* str) {
aoqi@0:   bool will_link;
aoqi@0:   ciField* field = str->get_field(will_link);
aoqi@0:   if (!will_link) {
aoqi@0:     trap(str, field->holder(), str->get_field_holder_index());
aoqi@0:   } else {
aoqi@0:     ciType* field_type = field->type();
aoqi@0:     if (!field_type->is_loaded()) {
aoqi@0:       // Normally, we need the field's type to be loaded if we are to
aoqi@0:       // do anything interesting with its value.
aoqi@0:       // We used to do this:  trap(str, str->get_field_signature_index());
aoqi@0:       //
aoqi@0:       // There is one good reason not to trap here.  Execution can
aoqi@0:       // get past this "getfield" or "getstatic" if the value of
aoqi@0:       // the field is null.  As long as the value is null, the class
aoqi@0:       // does not need to be loaded!  The compiler must assume that
aoqi@0:       // the value of the unloaded class reference is null; if the code
aoqi@0:       // ever sees a non-null value, loading has occurred.
aoqi@0:       //
aoqi@0:       // This actually happens often enough to be annoying.  If the
aoqi@0:       // compiler throws an uncommon trap at this bytecode, you can
aoqi@0:       // get an endless loop of recompilations, when all the code
aoqi@0:       // needs to do is load a series of null values.  Also, a trap
aoqi@0:       // here can make an OSR entry point unreachable, triggering the
aoqi@0:       // assert on non_osr_block in ciTypeFlow::get_start_state.
aoqi@0:       // (See bug 4379915.)
aoqi@0:       do_null_assert(field_type->as_klass());
aoqi@0:     } else {
aoqi@0:       push_translate(field_type);
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::do_invoke
aoqi@0: void ciTypeFlow::StateVector::do_invoke(ciBytecodeStream* str,
aoqi@0:                                         bool has_receiver) {
aoqi@0:   bool will_link;
aoqi@0:   ciSignature* declared_signature = NULL;
aoqi@0:   ciMethod* callee = str->get_method(will_link, &declared_signature);
aoqi@0:   assert(declared_signature != NULL, "cannot be null");
aoqi@0:   if (!will_link) {
aoqi@0:     // We weren't able to find the method.
aoqi@0:     if (str->cur_bc() == Bytecodes::_invokedynamic) {
aoqi@0:       trap(str, NULL,
aoqi@0:            Deoptimization::make_trap_request
aoqi@0:            (Deoptimization::Reason_uninitialized,
aoqi@0:             Deoptimization::Action_reinterpret));
aoqi@0:     } else {
aoqi@0:       ciKlass* unloaded_holder = callee->holder();
aoqi@0:       trap(str, unloaded_holder, str->get_method_holder_index());
aoqi@0:     }
aoqi@0:   } else {
aoqi@0:     // We are using the declared signature here because it might be
aoqi@0:     // different from the callee signature (Cf. invokedynamic and
aoqi@0:     // invokehandle).
aoqi@0:     ciSignatureStream sigstr(declared_signature);
aoqi@0:     const int arg_size = declared_signature->size();
aoqi@0:     const int stack_base = stack_size() - arg_size;
aoqi@0:     int i = 0;
aoqi@0:     for( ; !sigstr.at_return_type(); sigstr.next()) {
aoqi@0:       ciType* type = sigstr.type();
aoqi@0:       ciType* stack_type = type_at(stack(stack_base + i++));
aoqi@0:       // Do I want to check this type?
aoqi@0:       // assert(stack_type->is_subtype_of(type), "bad type for field value");
aoqi@0:       if (type->is_two_word()) {
aoqi@0:         ciType* stack_type2 = type_at(stack(stack_base + i++));
aoqi@0:         assert(stack_type2->equals(half_type(type)), "must be 2nd half");
aoqi@0:       }
aoqi@0:     }
aoqi@0:     assert(arg_size == i, "must match");
aoqi@0:     for (int j = 0; j < arg_size; j++) {
aoqi@0:       pop();
aoqi@0:     }
aoqi@0:     if (has_receiver) {
aoqi@0:       // Check this?
aoqi@0:       pop_object();
aoqi@0:     }
aoqi@0:     assert(!sigstr.is_done(), "must have return type");
aoqi@0:     ciType* return_type = sigstr.type();
aoqi@0:     if (!return_type->is_void()) {
aoqi@0:       if (!return_type->is_loaded()) {
aoqi@0:         // As in do_getstatic(), generally speaking, we need the return type to
aoqi@0:         // be loaded if we are to do anything interesting with its value.
aoqi@0:         // We used to do this:  trap(str, str->get_method_signature_index());
aoqi@0:         //
aoqi@0:         // We do not trap here since execution can get past this invoke if
aoqi@0:         // the return value is null.  As long as the value is null, the class
aoqi@0:         // does not need to be loaded!  The compiler must assume that
aoqi@0:         // the value of the unloaded class reference is null; if the code
aoqi@0:         // ever sees a non-null value, loading has occurred.
aoqi@0:         //
aoqi@0:         // See do_getstatic() for similar explanation, as well as bug 4684993.
aoqi@0:         do_null_assert(return_type->as_klass());
aoqi@0:       } else {
aoqi@0:         push_translate(return_type);
aoqi@0:       }
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::do_jsr
aoqi@0: void ciTypeFlow::StateVector::do_jsr(ciBytecodeStream* str) {
aoqi@0:   push(ciReturnAddress::make(str->next_bci()));
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::do_ldc
aoqi@0: void ciTypeFlow::StateVector::do_ldc(ciBytecodeStream* str) {
aoqi@0:   ciConstant con = str->get_constant();
aoqi@0:   BasicType basic_type = con.basic_type();
aoqi@0:   if (basic_type == T_ILLEGAL) {
aoqi@0:     // OutOfMemoryError in the CI while loading constant
aoqi@0:     push_null();
aoqi@0:     outer()->record_failure("ldc did not link");
aoqi@0:     return;
aoqi@0:   }
aoqi@0:   if (basic_type == T_OBJECT || basic_type == T_ARRAY) {
aoqi@0:     ciObject* obj = con.as_object();
aoqi@0:     if (obj->is_null_object()) {
aoqi@0:       push_null();
aoqi@0:     } else {
vlivanov@7288:       assert(obj->is_instance() || obj->is_array(), "must be java_mirror of klass");
aoqi@0:       push_object(obj->klass());
aoqi@0:     }
aoqi@0:   } else {
aoqi@0:     push_translate(ciType::make(basic_type));
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::do_multianewarray
aoqi@0: void ciTypeFlow::StateVector::do_multianewarray(ciBytecodeStream* str) {
aoqi@0:   int dimensions = str->get_dimensions();
aoqi@0:   bool will_link;
aoqi@0:   ciArrayKlass* array_klass = str->get_klass(will_link)->as_array_klass();
aoqi@0:   if (!will_link) {
aoqi@0:     trap(str, array_klass, str->get_klass_index());
aoqi@0:   } else {
aoqi@0:     for (int i = 0; i < dimensions; i++) {
aoqi@0:       pop_int();
aoqi@0:     }
aoqi@0:     push_object(array_klass);
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::do_new
aoqi@0: void ciTypeFlow::StateVector::do_new(ciBytecodeStream* str) {
aoqi@0:   bool will_link;
aoqi@0:   ciKlass* klass = str->get_klass(will_link);
aoqi@0:   if (!will_link || str->is_unresolved_klass()) {
aoqi@0:     trap(str, klass, str->get_klass_index());
aoqi@0:   } else {
aoqi@0:     push_object(klass);
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::do_newarray
aoqi@0: void ciTypeFlow::StateVector::do_newarray(ciBytecodeStream* str) {
aoqi@0:   pop_int();
aoqi@0:   ciKlass* klass = ciTypeArrayKlass::make((BasicType)str->get_index());
aoqi@0:   push_object(klass);
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::do_putfield
aoqi@0: void ciTypeFlow::StateVector::do_putfield(ciBytecodeStream* str) {
aoqi@0:   do_putstatic(str);
aoqi@0:   if (_trap_bci != -1)  return;  // unloaded field holder, etc.
aoqi@0:   // could add assert here for type of object.
aoqi@0:   pop_object();
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::do_putstatic
aoqi@0: void ciTypeFlow::StateVector::do_putstatic(ciBytecodeStream* str) {
aoqi@0:   bool will_link;
aoqi@0:   ciField* field = str->get_field(will_link);
aoqi@0:   if (!will_link) {
aoqi@0:     trap(str, field->holder(), str->get_field_holder_index());
aoqi@0:   } else {
aoqi@0:     ciType* field_type = field->type();
aoqi@0:     ciType* type = pop_value();
aoqi@0:     // Do I want to check this type?
aoqi@0:     //      assert(type->is_subtype_of(field_type), "bad type for field value");
aoqi@0:     if (field_type->is_two_word()) {
aoqi@0:       ciType* type2 = pop_value();
aoqi@0:       assert(type2->is_two_word(), "must be 2nd half");
aoqi@0:       assert(type == half_type(type2), "must be 2nd half");
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::do_ret
aoqi@0: void ciTypeFlow::StateVector::do_ret(ciBytecodeStream* str) {
aoqi@0:   Cell index = local(str->get_index());
aoqi@0: 
aoqi@0:   ciType* address = type_at(index);
aoqi@0:   assert(address->is_return_address(), "bad return address");
aoqi@0:   set_type_at(index, bottom_type());
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::trap
aoqi@0: //
aoqi@0: // Stop interpretation of this path with a trap.
aoqi@0: void ciTypeFlow::StateVector::trap(ciBytecodeStream* str, ciKlass* klass, int index) {
aoqi@0:   _trap_bci = str->cur_bci();
aoqi@0:   _trap_index = index;
aoqi@0: 
aoqi@0:   // Log information about this trap:
aoqi@0:   CompileLog* log = outer()->env()->log();
aoqi@0:   if (log != NULL) {
aoqi@0:     int mid = log->identify(outer()->method());
aoqi@0:     int kid = (klass == NULL)? -1: log->identify(klass);
aoqi@0:     log->begin_elem("uncommon_trap method='%d' bci='%d'", mid, str->cur_bci());
aoqi@0:     char buf[100];
aoqi@0:     log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
aoqi@0:                                                           index));
aoqi@0:     if (kid >= 0)
aoqi@0:       log->print(" klass='%d'", kid);
aoqi@0:     log->end_elem();
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::do_null_assert
aoqi@0: // Corresponds to graphKit::do_null_assert.
aoqi@0: void ciTypeFlow::StateVector::do_null_assert(ciKlass* unloaded_klass) {
aoqi@0:   if (unloaded_klass->is_loaded()) {
aoqi@0:     // We failed to link, but we can still compute with this class,
aoqi@0:     // since it is loaded somewhere.  The compiler will uncommon_trap
aoqi@0:     // if the object is not null, but the typeflow pass can not assume
aoqi@0:     // that the object will be null, otherwise it may incorrectly tell
aoqi@0:     // the parser that an object is known to be null. 4761344, 4807707
aoqi@0:     push_object(unloaded_klass);
aoqi@0:   } else {
aoqi@0:     // The class is not loaded anywhere.  It is safe to model the
aoqi@0:     // null in the typestates, because we can compile in a null check
aoqi@0:     // which will deoptimize us if someone manages to load the
aoqi@0:     // class later.
aoqi@0:     push_null();
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::apply_one_bytecode
aoqi@0: //
aoqi@0: // Apply the effect of one bytecode to this StateVector
aoqi@0: bool ciTypeFlow::StateVector::apply_one_bytecode(ciBytecodeStream* str) {
aoqi@0:   _trap_bci = -1;
aoqi@0:   _trap_index = 0;
aoqi@0: 
aoqi@0:   if (CITraceTypeFlow) {
aoqi@0:     tty->print_cr(">> Interpreting bytecode %d:%s", str->cur_bci(),
aoqi@0:                   Bytecodes::name(str->cur_bc()));
aoqi@0:   }
aoqi@0: 
aoqi@0:   switch(str->cur_bc()) {
aoqi@0:   case Bytecodes::_aaload: do_aaload(str);                       break;
aoqi@0: 
aoqi@0:   case Bytecodes::_aastore:
aoqi@0:     {
aoqi@0:       pop_object();
aoqi@0:       pop_int();
aoqi@0:       pop_objArray();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_aconst_null:
aoqi@0:     {
aoqi@0:       push_null();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_aload:   load_local_object(str->get_index());    break;
aoqi@0:   case Bytecodes::_aload_0: load_local_object(0);                   break;
aoqi@0:   case Bytecodes::_aload_1: load_local_object(1);                   break;
aoqi@0:   case Bytecodes::_aload_2: load_local_object(2);                   break;
aoqi@0:   case Bytecodes::_aload_3: load_local_object(3);                   break;
aoqi@0: 
aoqi@0:   case Bytecodes::_anewarray:
aoqi@0:     {
aoqi@0:       pop_int();
aoqi@0:       bool will_link;
aoqi@0:       ciKlass* element_klass = str->get_klass(will_link);
aoqi@0:       if (!will_link) {
aoqi@0:         trap(str, element_klass, str->get_klass_index());
aoqi@0:       } else {
aoqi@0:         push_object(ciObjArrayKlass::make(element_klass));
aoqi@0:       }
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_areturn:
aoqi@0:   case Bytecodes::_ifnonnull:
aoqi@0:   case Bytecodes::_ifnull:
aoqi@0:     {
aoqi@0:       pop_object();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_monitorenter:
aoqi@0:     {
aoqi@0:       pop_object();
aoqi@0:       set_monitor_count(monitor_count() + 1);
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_monitorexit:
aoqi@0:     {
aoqi@0:       pop_object();
aoqi@0:       assert(monitor_count() > 0, "must be a monitor to exit from");
aoqi@0:       set_monitor_count(monitor_count() - 1);
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_arraylength:
aoqi@0:     {
aoqi@0:       pop_array();
aoqi@0:       push_int();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_astore:   store_local_object(str->get_index());  break;
aoqi@0:   case Bytecodes::_astore_0: store_local_object(0);                 break;
aoqi@0:   case Bytecodes::_astore_1: store_local_object(1);                 break;
aoqi@0:   case Bytecodes::_astore_2: store_local_object(2);                 break;
aoqi@0:   case Bytecodes::_astore_3: store_local_object(3);                 break;
aoqi@0: 
aoqi@0:   case Bytecodes::_athrow:
aoqi@0:     {
aoqi@0:       NEEDS_CLEANUP;
aoqi@0:       pop_object();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_baload:
aoqi@0:   case Bytecodes::_caload:
aoqi@0:   case Bytecodes::_iaload:
aoqi@0:   case Bytecodes::_saload:
aoqi@0:     {
aoqi@0:       pop_int();
aoqi@0:       ciTypeArrayKlass* array_klass = pop_typeArray();
aoqi@0:       // Put assert here for right type?
aoqi@0:       push_int();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_bastore:
aoqi@0:   case Bytecodes::_castore:
aoqi@0:   case Bytecodes::_iastore:
aoqi@0:   case Bytecodes::_sastore:
aoqi@0:     {
aoqi@0:       pop_int();
aoqi@0:       pop_int();
aoqi@0:       pop_typeArray();
aoqi@0:       // assert here?
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_bipush:
aoqi@0:   case Bytecodes::_iconst_m1:
aoqi@0:   case Bytecodes::_iconst_0:
aoqi@0:   case Bytecodes::_iconst_1:
aoqi@0:   case Bytecodes::_iconst_2:
aoqi@0:   case Bytecodes::_iconst_3:
aoqi@0:   case Bytecodes::_iconst_4:
aoqi@0:   case Bytecodes::_iconst_5:
aoqi@0:   case Bytecodes::_sipush:
aoqi@0:     {
aoqi@0:       push_int();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_checkcast: do_checkcast(str);                  break;
aoqi@0: 
aoqi@0:   case Bytecodes::_d2f:
aoqi@0:     {
aoqi@0:       pop_double();
aoqi@0:       push_float();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_d2i:
aoqi@0:     {
aoqi@0:       pop_double();
aoqi@0:       push_int();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_d2l:
aoqi@0:     {
aoqi@0:       pop_double();
aoqi@0:       push_long();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_dadd:
aoqi@0:   case Bytecodes::_ddiv:
aoqi@0:   case Bytecodes::_dmul:
aoqi@0:   case Bytecodes::_drem:
aoqi@0:   case Bytecodes::_dsub:
aoqi@0:     {
aoqi@0:       pop_double();
aoqi@0:       pop_double();
aoqi@0:       push_double();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_daload:
aoqi@0:     {
aoqi@0:       pop_int();
aoqi@0:       ciTypeArrayKlass* array_klass = pop_typeArray();
aoqi@0:       // Put assert here for right type?
aoqi@0:       push_double();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_dastore:
aoqi@0:     {
aoqi@0:       pop_double();
aoqi@0:       pop_int();
aoqi@0:       pop_typeArray();
aoqi@0:       // assert here?
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_dcmpg:
aoqi@0:   case Bytecodes::_dcmpl:
aoqi@0:     {
aoqi@0:       pop_double();
aoqi@0:       pop_double();
aoqi@0:       push_int();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_dconst_0:
aoqi@0:   case Bytecodes::_dconst_1:
aoqi@0:     {
aoqi@0:       push_double();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_dload:   load_local_double(str->get_index());    break;
aoqi@0:   case Bytecodes::_dload_0: load_local_double(0);                   break;
aoqi@0:   case Bytecodes::_dload_1: load_local_double(1);                   break;
aoqi@0:   case Bytecodes::_dload_2: load_local_double(2);                   break;
aoqi@0:   case Bytecodes::_dload_3: load_local_double(3);                   break;
aoqi@0: 
aoqi@0:   case Bytecodes::_dneg:
aoqi@0:     {
aoqi@0:       pop_double();
aoqi@0:       push_double();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_dreturn:
aoqi@0:     {
aoqi@0:       pop_double();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_dstore:   store_local_double(str->get_index());  break;
aoqi@0:   case Bytecodes::_dstore_0: store_local_double(0);                 break;
aoqi@0:   case Bytecodes::_dstore_1: store_local_double(1);                 break;
aoqi@0:   case Bytecodes::_dstore_2: store_local_double(2);                 break;
aoqi@0:   case Bytecodes::_dstore_3: store_local_double(3);                 break;
aoqi@0: 
aoqi@0:   case Bytecodes::_dup:
aoqi@0:     {
aoqi@0:       push(type_at_tos());
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_dup_x1:
aoqi@0:     {
aoqi@0:       ciType* value1 = pop_value();
aoqi@0:       ciType* value2 = pop_value();
aoqi@0:       push(value1);
aoqi@0:       push(value2);
aoqi@0:       push(value1);
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_dup_x2:
aoqi@0:     {
aoqi@0:       ciType* value1 = pop_value();
aoqi@0:       ciType* value2 = pop_value();
aoqi@0:       ciType* value3 = pop_value();
aoqi@0:       push(value1);
aoqi@0:       push(value3);
aoqi@0:       push(value2);
aoqi@0:       push(value1);
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_dup2:
aoqi@0:     {
aoqi@0:       ciType* value1 = pop_value();
aoqi@0:       ciType* value2 = pop_value();
aoqi@0:       push(value2);
aoqi@0:       push(value1);
aoqi@0:       push(value2);
aoqi@0:       push(value1);
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_dup2_x1:
aoqi@0:     {
aoqi@0:       ciType* value1 = pop_value();
aoqi@0:       ciType* value2 = pop_value();
aoqi@0:       ciType* value3 = pop_value();
aoqi@0:       push(value2);
aoqi@0:       push(value1);
aoqi@0:       push(value3);
aoqi@0:       push(value2);
aoqi@0:       push(value1);
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_dup2_x2:
aoqi@0:     {
aoqi@0:       ciType* value1 = pop_value();
aoqi@0:       ciType* value2 = pop_value();
aoqi@0:       ciType* value3 = pop_value();
aoqi@0:       ciType* value4 = pop_value();
aoqi@0:       push(value2);
aoqi@0:       push(value1);
aoqi@0:       push(value4);
aoqi@0:       push(value3);
aoqi@0:       push(value2);
aoqi@0:       push(value1);
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_f2d:
aoqi@0:     {
aoqi@0:       pop_float();
aoqi@0:       push_double();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_f2i:
aoqi@0:     {
aoqi@0:       pop_float();
aoqi@0:       push_int();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_f2l:
aoqi@0:     {
aoqi@0:       pop_float();
aoqi@0:       push_long();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_fadd:
aoqi@0:   case Bytecodes::_fdiv:
aoqi@0:   case Bytecodes::_fmul:
aoqi@0:   case Bytecodes::_frem:
aoqi@0:   case Bytecodes::_fsub:
aoqi@0:     {
aoqi@0:       pop_float();
aoqi@0:       pop_float();
aoqi@0:       push_float();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_faload:
aoqi@0:     {
aoqi@0:       pop_int();
aoqi@0:       ciTypeArrayKlass* array_klass = pop_typeArray();
aoqi@0:       // Put assert here.
aoqi@0:       push_float();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_fastore:
aoqi@0:     {
aoqi@0:       pop_float();
aoqi@0:       pop_int();
aoqi@0:       ciTypeArrayKlass* array_klass = pop_typeArray();
aoqi@0:       // Put assert here.
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_fcmpg:
aoqi@0:   case Bytecodes::_fcmpl:
aoqi@0:     {
aoqi@0:       pop_float();
aoqi@0:       pop_float();
aoqi@0:       push_int();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_fconst_0:
aoqi@0:   case Bytecodes::_fconst_1:
aoqi@0:   case Bytecodes::_fconst_2:
aoqi@0:     {
aoqi@0:       push_float();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_fload:   load_local_float(str->get_index());     break;
aoqi@0:   case Bytecodes::_fload_0: load_local_float(0);                    break;
aoqi@0:   case Bytecodes::_fload_1: load_local_float(1);                    break;
aoqi@0:   case Bytecodes::_fload_2: load_local_float(2);                    break;
aoqi@0:   case Bytecodes::_fload_3: load_local_float(3);                    break;
aoqi@0: 
aoqi@0:   case Bytecodes::_fneg:
aoqi@0:     {
aoqi@0:       pop_float();
aoqi@0:       push_float();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_freturn:
aoqi@0:     {
aoqi@0:       pop_float();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_fstore:    store_local_float(str->get_index());   break;
aoqi@0:   case Bytecodes::_fstore_0:  store_local_float(0);                  break;
aoqi@0:   case Bytecodes::_fstore_1:  store_local_float(1);                  break;
aoqi@0:   case Bytecodes::_fstore_2:  store_local_float(2);                  break;
aoqi@0:   case Bytecodes::_fstore_3:  store_local_float(3);                  break;
aoqi@0: 
aoqi@0:   case Bytecodes::_getfield:  do_getfield(str);                      break;
aoqi@0:   case Bytecodes::_getstatic: do_getstatic(str);                     break;
aoqi@0: 
aoqi@0:   case Bytecodes::_goto:
aoqi@0:   case Bytecodes::_goto_w:
aoqi@0:   case Bytecodes::_nop:
aoqi@0:   case Bytecodes::_return:
aoqi@0:     {
aoqi@0:       // do nothing.
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_i2b:
aoqi@0:   case Bytecodes::_i2c:
aoqi@0:   case Bytecodes::_i2s:
aoqi@0:   case Bytecodes::_ineg:
aoqi@0:     {
aoqi@0:       pop_int();
aoqi@0:       push_int();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_i2d:
aoqi@0:     {
aoqi@0:       pop_int();
aoqi@0:       push_double();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_i2f:
aoqi@0:     {
aoqi@0:       pop_int();
aoqi@0:       push_float();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_i2l:
aoqi@0:     {
aoqi@0:       pop_int();
aoqi@0:       push_long();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_iadd:
aoqi@0:   case Bytecodes::_iand:
aoqi@0:   case Bytecodes::_idiv:
aoqi@0:   case Bytecodes::_imul:
aoqi@0:   case Bytecodes::_ior:
aoqi@0:   case Bytecodes::_irem:
aoqi@0:   case Bytecodes::_ishl:
aoqi@0:   case Bytecodes::_ishr:
aoqi@0:   case Bytecodes::_isub:
aoqi@0:   case Bytecodes::_iushr:
aoqi@0:   case Bytecodes::_ixor:
aoqi@0:     {
aoqi@0:       pop_int();
aoqi@0:       pop_int();
aoqi@0:       push_int();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_if_acmpeq:
aoqi@0:   case Bytecodes::_if_acmpne:
aoqi@0:     {
aoqi@0:       pop_object();
aoqi@0:       pop_object();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_if_icmpeq:
aoqi@0:   case Bytecodes::_if_icmpge:
aoqi@0:   case Bytecodes::_if_icmpgt:
aoqi@0:   case Bytecodes::_if_icmple:
aoqi@0:   case Bytecodes::_if_icmplt:
aoqi@0:   case Bytecodes::_if_icmpne:
aoqi@0:     {
aoqi@0:       pop_int();
aoqi@0:       pop_int();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_ifeq:
aoqi@0:   case Bytecodes::_ifle:
aoqi@0:   case Bytecodes::_iflt:
aoqi@0:   case Bytecodes::_ifge:
aoqi@0:   case Bytecodes::_ifgt:
aoqi@0:   case Bytecodes::_ifne:
aoqi@0:   case Bytecodes::_ireturn:
aoqi@0:   case Bytecodes::_lookupswitch:
aoqi@0:   case Bytecodes::_tableswitch:
aoqi@0:     {
aoqi@0:       pop_int();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_iinc:
aoqi@0:     {
aoqi@0:       int lnum = str->get_index();
aoqi@0:       check_int(local(lnum));
aoqi@0:       store_to_local(lnum);
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_iload:   load_local_int(str->get_index()); break;
aoqi@0:   case Bytecodes::_iload_0: load_local_int(0);                      break;
aoqi@0:   case Bytecodes::_iload_1: load_local_int(1);                      break;
aoqi@0:   case Bytecodes::_iload_2: load_local_int(2);                      break;
aoqi@0:   case Bytecodes::_iload_3: load_local_int(3);                      break;
aoqi@0: 
aoqi@0:   case Bytecodes::_instanceof:
aoqi@0:     {
aoqi@0:       // Check for uncommon trap:
aoqi@0:       do_checkcast(str);
aoqi@0:       pop_object();
aoqi@0:       push_int();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_invokeinterface: do_invoke(str, true);           break;
aoqi@0:   case Bytecodes::_invokespecial:   do_invoke(str, true);           break;
aoqi@0:   case Bytecodes::_invokestatic:    do_invoke(str, false);          break;
aoqi@0:   case Bytecodes::_invokevirtual:   do_invoke(str, true);           break;
aoqi@0:   case Bytecodes::_invokedynamic:   do_invoke(str, false);          break;
aoqi@0: 
aoqi@0:   case Bytecodes::_istore:   store_local_int(str->get_index());     break;
aoqi@0:   case Bytecodes::_istore_0: store_local_int(0);                    break;
aoqi@0:   case Bytecodes::_istore_1: store_local_int(1);                    break;
aoqi@0:   case Bytecodes::_istore_2: store_local_int(2);                    break;
aoqi@0:   case Bytecodes::_istore_3: store_local_int(3);                    break;
aoqi@0: 
aoqi@0:   case Bytecodes::_jsr:
aoqi@0:   case Bytecodes::_jsr_w: do_jsr(str);                              break;
aoqi@0: 
aoqi@0:   case Bytecodes::_l2d:
aoqi@0:     {
aoqi@0:       pop_long();
aoqi@0:       push_double();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_l2f:
aoqi@0:     {
aoqi@0:       pop_long();
aoqi@0:       push_float();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_l2i:
aoqi@0:     {
aoqi@0:       pop_long();
aoqi@0:       push_int();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_ladd:
aoqi@0:   case Bytecodes::_land:
aoqi@0:   case Bytecodes::_ldiv:
aoqi@0:   case Bytecodes::_lmul:
aoqi@0:   case Bytecodes::_lor:
aoqi@0:   case Bytecodes::_lrem:
aoqi@0:   case Bytecodes::_lsub:
aoqi@0:   case Bytecodes::_lxor:
aoqi@0:     {
aoqi@0:       pop_long();
aoqi@0:       pop_long();
aoqi@0:       push_long();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_laload:
aoqi@0:     {
aoqi@0:       pop_int();
aoqi@0:       ciTypeArrayKlass* array_klass = pop_typeArray();
aoqi@0:       // Put assert here for right type?
aoqi@0:       push_long();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_lastore:
aoqi@0:     {
aoqi@0:       pop_long();
aoqi@0:       pop_int();
aoqi@0:       pop_typeArray();
aoqi@0:       // assert here?
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_lcmp:
aoqi@0:     {
aoqi@0:       pop_long();
aoqi@0:       pop_long();
aoqi@0:       push_int();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_lconst_0:
aoqi@0:   case Bytecodes::_lconst_1:
aoqi@0:     {
aoqi@0:       push_long();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_ldc:
aoqi@0:   case Bytecodes::_ldc_w:
aoqi@0:   case Bytecodes::_ldc2_w:
aoqi@0:     {
aoqi@0:       do_ldc(str);
aoqi@0:       break;
aoqi@0:     }
aoqi@0: 
aoqi@0:   case Bytecodes::_lload:   load_local_long(str->get_index());      break;
aoqi@0:   case Bytecodes::_lload_0: load_local_long(0);                     break;
aoqi@0:   case Bytecodes::_lload_1: load_local_long(1);                     break;
aoqi@0:   case Bytecodes::_lload_2: load_local_long(2);                     break;
aoqi@0:   case Bytecodes::_lload_3: load_local_long(3);                     break;
aoqi@0: 
aoqi@0:   case Bytecodes::_lneg:
aoqi@0:     {
aoqi@0:       pop_long();
aoqi@0:       push_long();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_lreturn:
aoqi@0:     {
aoqi@0:       pop_long();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_lshl:
aoqi@0:   case Bytecodes::_lshr:
aoqi@0:   case Bytecodes::_lushr:
aoqi@0:     {
aoqi@0:       pop_int();
aoqi@0:       pop_long();
aoqi@0:       push_long();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_lstore:   store_local_long(str->get_index());    break;
aoqi@0:   case Bytecodes::_lstore_0: store_local_long(0);                   break;
aoqi@0:   case Bytecodes::_lstore_1: store_local_long(1);                   break;
aoqi@0:   case Bytecodes::_lstore_2: store_local_long(2);                   break;
aoqi@0:   case Bytecodes::_lstore_3: store_local_long(3);                   break;
aoqi@0: 
aoqi@0:   case Bytecodes::_multianewarray: do_multianewarray(str);          break;
aoqi@0: 
aoqi@0:   case Bytecodes::_new:      do_new(str);                           break;
aoqi@0: 
aoqi@0:   case Bytecodes::_newarray: do_newarray(str);                      break;
aoqi@0: 
aoqi@0:   case Bytecodes::_pop:
aoqi@0:     {
aoqi@0:       pop();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_pop2:
aoqi@0:     {
aoqi@0:       pop();
aoqi@0:       pop();
aoqi@0:       break;
aoqi@0:     }
aoqi@0: 
aoqi@0:   case Bytecodes::_putfield:       do_putfield(str);                 break;
aoqi@0:   case Bytecodes::_putstatic:      do_putstatic(str);                break;
aoqi@0: 
aoqi@0:   case Bytecodes::_ret: do_ret(str);                                 break;
aoqi@0: 
aoqi@0:   case Bytecodes::_swap:
aoqi@0:     {
aoqi@0:       ciType* value1 = pop_value();
aoqi@0:       ciType* value2 = pop_value();
aoqi@0:       push(value1);
aoqi@0:       push(value2);
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   case Bytecodes::_wide:
aoqi@0:   default:
aoqi@0:     {
aoqi@0:       // The iterator should skip this.
aoqi@0:       ShouldNotReachHere();
aoqi@0:       break;
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   if (CITraceTypeFlow) {
aoqi@0:     print_on(tty);
aoqi@0:   }
aoqi@0: 
aoqi@0:   return (_trap_bci != -1);
aoqi@0: }
aoqi@0: 
aoqi@0: #ifndef PRODUCT
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::print_cell_on
aoqi@0: void ciTypeFlow::StateVector::print_cell_on(outputStream* st, Cell c) const {
aoqi@0:   ciType* type = type_at(c);
aoqi@0:   if (type == top_type()) {
aoqi@0:     st->print("top");
aoqi@0:   } else if (type == bottom_type()) {
aoqi@0:     st->print("bottom");
aoqi@0:   } else if (type == null_type()) {
aoqi@0:     st->print("null");
aoqi@0:   } else if (type == long2_type()) {
aoqi@0:     st->print("long2");
aoqi@0:   } else if (type == double2_type()) {
aoqi@0:     st->print("double2");
aoqi@0:   } else if (is_int(type)) {
aoqi@0:     st->print("int");
aoqi@0:   } else if (is_long(type)) {
aoqi@0:     st->print("long");
aoqi@0:   } else if (is_float(type)) {
aoqi@0:     st->print("float");
aoqi@0:   } else if (is_double(type)) {
aoqi@0:     st->print("double");
aoqi@0:   } else if (type->is_return_address()) {
aoqi@0:     st->print("address(%d)", type->as_return_address()->bci());
aoqi@0:   } else {
aoqi@0:     if (type->is_klass()) {
aoqi@0:       type->as_klass()->name()->print_symbol_on(st);
aoqi@0:     } else {
aoqi@0:       st->print("UNEXPECTED TYPE");
aoqi@0:       type->print();
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::StateVector::print_on
aoqi@0: void ciTypeFlow::StateVector::print_on(outputStream* st) const {
aoqi@0:   int num_locals   = _outer->max_locals();
aoqi@0:   int num_stack    = stack_size();
aoqi@0:   int num_monitors = monitor_count();
aoqi@0:   st->print_cr("  State : locals %d, stack %d, monitors %d", num_locals, num_stack, num_monitors);
aoqi@0:   if (num_stack >= 0) {
aoqi@0:     int i;
aoqi@0:     for (i = 0; i < num_locals; i++) {
aoqi@0:       st->print("    local %2d : ", i);
aoqi@0:       print_cell_on(st, local(i));
aoqi@0:       st->cr();
aoqi@0:     }
aoqi@0:     for (i = 0; i < num_stack; i++) {
aoqi@0:       st->print("    stack %2d : ", i);
aoqi@0:       print_cell_on(st, stack(i));
aoqi@0:       st->cr();
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: #endif
aoqi@0: 
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::SuccIter::next
aoqi@0: //
aoqi@0: void ciTypeFlow::SuccIter::next() {
aoqi@0:   int succ_ct = _pred->successors()->length();
aoqi@0:   int next = _index + 1;
aoqi@0:   if (next < succ_ct) {
aoqi@0:     _index = next;
aoqi@0:     _succ = _pred->successors()->at(next);
aoqi@0:     return;
aoqi@0:   }
aoqi@0:   for (int i = next - succ_ct; i < _pred->exceptions()->length(); i++) {
aoqi@0:     // Do not compile any code for unloaded exception types.
aoqi@0:     // Following compiler passes are responsible for doing this also.
aoqi@0:     ciInstanceKlass* exception_klass = _pred->exc_klasses()->at(i);
aoqi@0:     if (exception_klass->is_loaded()) {
aoqi@0:       _index = next;
aoqi@0:       _succ = _pred->exceptions()->at(i);
aoqi@0:       return;
aoqi@0:     }
aoqi@0:     next++;
aoqi@0:   }
aoqi@0:   _index = -1;
aoqi@0:   _succ = NULL;
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::SuccIter::set_succ
aoqi@0: //
aoqi@0: void ciTypeFlow::SuccIter::set_succ(Block* succ) {
aoqi@0:   int succ_ct = _pred->successors()->length();
aoqi@0:   if (_index < succ_ct) {
aoqi@0:     _pred->successors()->at_put(_index, succ);
aoqi@0:   } else {
aoqi@0:     int idx = _index - succ_ct;
aoqi@0:     _pred->exceptions()->at_put(idx, succ);
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ciTypeFlow::Block
aoqi@0: //
aoqi@0: // A basic block.
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::Block::Block
aoqi@0: ciTypeFlow::Block::Block(ciTypeFlow* outer,
aoqi@0:                          ciBlock *ciblk,
aoqi@0:                          ciTypeFlow::JsrSet* jsrs) {
aoqi@0:   _ciblock = ciblk;
aoqi@0:   _exceptions = NULL;
aoqi@0:   _exc_klasses = NULL;
aoqi@0:   _successors = NULL;
aoqi@0:   _state = new (outer->arena()) StateVector(outer);
aoqi@0:   JsrSet* new_jsrs =
aoqi@0:     new (outer->arena()) JsrSet(outer->arena(), jsrs->size());
aoqi@0:   jsrs->copy_into(new_jsrs);
aoqi@0:   _jsrs = new_jsrs;
aoqi@0:   _next = NULL;
aoqi@0:   _on_work_list = false;
aoqi@0:   _backedge_copy = false;
aoqi@0:   _has_monitorenter = false;
aoqi@0:   _trap_bci = -1;
aoqi@0:   _trap_index = 0;
aoqi@0:   df_init();
aoqi@0: 
aoqi@0:   if (CITraceTypeFlow) {
aoqi@0:     tty->print_cr(">> Created new block");
aoqi@0:     print_on(tty);
aoqi@0:   }
aoqi@0: 
aoqi@0:   assert(this->outer() == outer, "outer link set up");
aoqi@0:   assert(!outer->have_block_count(), "must not have mapped blocks yet");
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::Block::df_init
aoqi@0: void ciTypeFlow::Block::df_init() {
aoqi@0:   _pre_order = -1; assert(!has_pre_order(), "");
aoqi@0:   _post_order = -1; assert(!has_post_order(), "");
aoqi@0:   _loop = NULL;
aoqi@0:   _irreducible_entry = false;
aoqi@0:   _rpo_next = NULL;
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::Block::successors
aoqi@0: //
aoqi@0: // Get the successors for this Block.
aoqi@0: GrowableArray<ciTypeFlow::Block*>*
aoqi@0: ciTypeFlow::Block::successors(ciBytecodeStream* str,
aoqi@0:                               ciTypeFlow::StateVector* state,
aoqi@0:                               ciTypeFlow::JsrSet* jsrs) {
aoqi@0:   if (_successors == NULL) {
aoqi@0:     if (CITraceTypeFlow) {
aoqi@0:       tty->print(">> Computing successors for block ");
aoqi@0:       print_value_on(tty);
aoqi@0:       tty->cr();
aoqi@0:     }
aoqi@0: 
aoqi@0:     ciTypeFlow* analyzer = outer();
aoqi@0:     Arena* arena = analyzer->arena();
aoqi@0:     Block* block = NULL;
aoqi@0:     bool has_successor = !has_trap() &&
aoqi@0:                          (control() != ciBlock::fall_through_bci || limit() < analyzer->code_size());
aoqi@0:     if (!has_successor) {
aoqi@0:       _successors =
aoqi@0:         new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
aoqi@0:       // No successors
aoqi@0:     } else if (control() == ciBlock::fall_through_bci) {
aoqi@0:       assert(str->cur_bci() == limit(), "bad block end");
aoqi@0:       // This block simply falls through to the next.
aoqi@0:       _successors =
aoqi@0:         new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
aoqi@0: 
aoqi@0:       Block* block = analyzer->block_at(limit(), _jsrs);
aoqi@0:       assert(_successors->length() == FALL_THROUGH, "");
aoqi@0:       _successors->append(block);
aoqi@0:     } else {
aoqi@0:       int current_bci = str->cur_bci();
aoqi@0:       int next_bci = str->next_bci();
aoqi@0:       int branch_bci = -1;
aoqi@0:       Block* target = NULL;
aoqi@0:       assert(str->next_bci() == limit(), "bad block end");
aoqi@0:       // This block is not a simple fall-though.  Interpret
aoqi@0:       // the current bytecode to find our successors.
aoqi@0:       switch (str->cur_bc()) {
aoqi@0:       case Bytecodes::_ifeq:         case Bytecodes::_ifne:
aoqi@0:       case Bytecodes::_iflt:         case Bytecodes::_ifge:
aoqi@0:       case Bytecodes::_ifgt:         case Bytecodes::_ifle:
aoqi@0:       case Bytecodes::_if_icmpeq:    case Bytecodes::_if_icmpne:
aoqi@0:       case Bytecodes::_if_icmplt:    case Bytecodes::_if_icmpge:
aoqi@0:       case Bytecodes::_if_icmpgt:    case Bytecodes::_if_icmple:
aoqi@0:       case Bytecodes::_if_acmpeq:    case Bytecodes::_if_acmpne:
aoqi@0:       case Bytecodes::_ifnull:       case Bytecodes::_ifnonnull:
aoqi@0:         // Our successors are the branch target and the next bci.
aoqi@0:         branch_bci = str->get_dest();
aoqi@0:         _successors =
aoqi@0:           new (arena) GrowableArray<Block*>(arena, 2, 0, NULL);
aoqi@0:         assert(_successors->length() == IF_NOT_TAKEN, "");
aoqi@0:         _successors->append(analyzer->block_at(next_bci, jsrs));
aoqi@0:         assert(_successors->length() == IF_TAKEN, "");
aoqi@0:         _successors->append(analyzer->block_at(branch_bci, jsrs));
aoqi@0:         break;
aoqi@0: 
aoqi@0:       case Bytecodes::_goto:
aoqi@0:         branch_bci = str->get_dest();
aoqi@0:         _successors =
aoqi@0:           new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
aoqi@0:         assert(_successors->length() == GOTO_TARGET, "");
aoqi@0:         _successors->append(analyzer->block_at(branch_bci, jsrs));
aoqi@0:         break;
aoqi@0: 
aoqi@0:       case Bytecodes::_jsr:
aoqi@0:         branch_bci = str->get_dest();
aoqi@0:         _successors =
aoqi@0:           new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
aoqi@0:         assert(_successors->length() == GOTO_TARGET, "");
aoqi@0:         _successors->append(analyzer->block_at(branch_bci, jsrs));
aoqi@0:         break;
aoqi@0: 
aoqi@0:       case Bytecodes::_goto_w:
aoqi@0:       case Bytecodes::_jsr_w:
aoqi@0:         _successors =
aoqi@0:           new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
aoqi@0:         assert(_successors->length() == GOTO_TARGET, "");
aoqi@0:         _successors->append(analyzer->block_at(str->get_far_dest(), jsrs));
aoqi@0:         break;
aoqi@0: 
aoqi@0:       case Bytecodes::_tableswitch:  {
aoqi@0:         Bytecode_tableswitch tableswitch(str);
aoqi@0: 
aoqi@0:         int len = tableswitch.length();
aoqi@0:         _successors =
aoqi@0:           new (arena) GrowableArray<Block*>(arena, len+1, 0, NULL);
aoqi@0:         int bci = current_bci + tableswitch.default_offset();
aoqi@0:         Block* block = analyzer->block_at(bci, jsrs);
aoqi@0:         assert(_successors->length() == SWITCH_DEFAULT, "");
aoqi@0:         _successors->append(block);
aoqi@0:         while (--len >= 0) {
aoqi@0:           int bci = current_bci + tableswitch.dest_offset_at(len);
aoqi@0:           block = analyzer->block_at(bci, jsrs);
aoqi@0:           assert(_successors->length() >= SWITCH_CASES, "");
aoqi@0:           _successors->append_if_missing(block);
aoqi@0:         }
aoqi@0:         break;
aoqi@0:       }
aoqi@0: 
aoqi@0:       case Bytecodes::_lookupswitch: {
aoqi@0:         Bytecode_lookupswitch lookupswitch(str);
aoqi@0: 
aoqi@0:         int npairs = lookupswitch.number_of_pairs();
aoqi@0:         _successors =
aoqi@0:           new (arena) GrowableArray<Block*>(arena, npairs+1, 0, NULL);
aoqi@0:         int bci = current_bci + lookupswitch.default_offset();
aoqi@0:         Block* block = analyzer->block_at(bci, jsrs);
aoqi@0:         assert(_successors->length() == SWITCH_DEFAULT, "");
aoqi@0:         _successors->append(block);
aoqi@0:         while(--npairs >= 0) {
aoqi@0:           LookupswitchPair pair = lookupswitch.pair_at(npairs);
aoqi@0:           int bci = current_bci + pair.offset();
aoqi@0:           Block* block = analyzer->block_at(bci, jsrs);
aoqi@0:           assert(_successors->length() >= SWITCH_CASES, "");
aoqi@0:           _successors->append_if_missing(block);
aoqi@0:         }
aoqi@0:         break;
aoqi@0:       }
aoqi@0: 
aoqi@0:       case Bytecodes::_athrow:     case Bytecodes::_ireturn:
aoqi@0:       case Bytecodes::_lreturn:    case Bytecodes::_freturn:
aoqi@0:       case Bytecodes::_dreturn:    case Bytecodes::_areturn:
aoqi@0:       case Bytecodes::_return:
aoqi@0:         _successors =
aoqi@0:           new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
aoqi@0:         // No successors
aoqi@0:         break;
aoqi@0: 
aoqi@0:       case Bytecodes::_ret: {
aoqi@0:         _successors =
aoqi@0:           new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
aoqi@0: 
aoqi@0:         Cell local = state->local(str->get_index());
aoqi@0:         ciType* return_address = state->type_at(local);
aoqi@0:         assert(return_address->is_return_address(), "verify: wrong type");
aoqi@0:         int bci = return_address->as_return_address()->bci();
aoqi@0:         assert(_successors->length() == GOTO_TARGET, "");
aoqi@0:         _successors->append(analyzer->block_at(bci, jsrs));
aoqi@0:         break;
aoqi@0:       }
aoqi@0: 
aoqi@0:       case Bytecodes::_wide:
aoqi@0:       default:
aoqi@0:         ShouldNotReachHere();
aoqi@0:         break;
aoqi@0:       }
aoqi@0:     }
aoqi@0:   }
aoqi@0:   return _successors;
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::Block:compute_exceptions
aoqi@0: //
aoqi@0: // Compute the exceptional successors and types for this Block.
aoqi@0: void ciTypeFlow::Block::compute_exceptions() {
aoqi@0:   assert(_exceptions == NULL && _exc_klasses == NULL, "repeat");
aoqi@0: 
aoqi@0:   if (CITraceTypeFlow) {
aoqi@0:     tty->print(">> Computing exceptions for block ");
aoqi@0:     print_value_on(tty);
aoqi@0:     tty->cr();
aoqi@0:   }
aoqi@0: 
aoqi@0:   ciTypeFlow* analyzer = outer();
aoqi@0:   Arena* arena = analyzer->arena();
aoqi@0: 
aoqi@0:   // Any bci in the block will do.
aoqi@0:   ciExceptionHandlerStream str(analyzer->method(), start());
aoqi@0: 
aoqi@0:   // Allocate our growable arrays.
aoqi@0:   int exc_count = str.count();
aoqi@0:   _exceptions = new (arena) GrowableArray<Block*>(arena, exc_count, 0, NULL);
aoqi@0:   _exc_klasses = new (arena) GrowableArray<ciInstanceKlass*>(arena, exc_count,
aoqi@0:                                                              0, NULL);
aoqi@0: 
aoqi@0:   for ( ; !str.is_done(); str.next()) {
aoqi@0:     ciExceptionHandler* handler = str.handler();
aoqi@0:     int bci = handler->handler_bci();
aoqi@0:     ciInstanceKlass* klass = NULL;
aoqi@0:     if (bci == -1) {
aoqi@0:       // There is no catch all.  It is possible to exit the method.
aoqi@0:       break;
aoqi@0:     }
aoqi@0:     if (handler->is_catch_all()) {
aoqi@0:       klass = analyzer->env()->Throwable_klass();
aoqi@0:     } else {
aoqi@0:       klass = handler->catch_klass();
aoqi@0:     }
aoqi@0:     _exceptions->append(analyzer->block_at(bci, _jsrs));
aoqi@0:     _exc_klasses->append(klass);
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::Block::set_backedge_copy
aoqi@0: // Use this only to make a pre-existing public block into a backedge copy.
aoqi@0: void ciTypeFlow::Block::set_backedge_copy(bool z) {
aoqi@0:   assert(z || (z == is_backedge_copy()), "cannot make a backedge copy public");
aoqi@0:   _backedge_copy = z;
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::Block::is_clonable_exit
aoqi@0: //
aoqi@0: // At most 2 normal successors, one of which continues looping,
aoqi@0: // and all exceptional successors must exit.
aoqi@0: bool ciTypeFlow::Block::is_clonable_exit(ciTypeFlow::Loop* lp) {
aoqi@0:   int normal_cnt  = 0;
aoqi@0:   int in_loop_cnt = 0;
aoqi@0:   for (SuccIter iter(this); !iter.done(); iter.next()) {
aoqi@0:     Block* succ = iter.succ();
aoqi@0:     if (iter.is_normal_ctrl()) {
aoqi@0:       if (++normal_cnt > 2) return false;
aoqi@0:       if (lp->contains(succ->loop())) {
aoqi@0:         if (++in_loop_cnt > 1) return false;
aoqi@0:       }
aoqi@0:     } else {
aoqi@0:       if (lp->contains(succ->loop())) return false;
aoqi@0:     }
aoqi@0:   }
aoqi@0:   return in_loop_cnt == 1;
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::Block::looping_succ
aoqi@0: //
aoqi@0: ciTypeFlow::Block* ciTypeFlow::Block::looping_succ(ciTypeFlow::Loop* lp) {
aoqi@0:   assert(successors()->length() <= 2, "at most 2 normal successors");
aoqi@0:   for (SuccIter iter(this); !iter.done(); iter.next()) {
aoqi@0:     Block* succ = iter.succ();
aoqi@0:     if (lp->contains(succ->loop())) {
aoqi@0:       return succ;
aoqi@0:     }
aoqi@0:   }
aoqi@0:   return NULL;
aoqi@0: }
aoqi@0: 
aoqi@0: #ifndef PRODUCT
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::Block::print_value_on
aoqi@0: void ciTypeFlow::Block::print_value_on(outputStream* st) const {
aoqi@0:   if (has_pre_order()) st->print("#%-2d ", pre_order());
aoqi@0:   if (has_rpo())       st->print("rpo#%-2d ", rpo());
aoqi@0:   st->print("[%d - %d)", start(), limit());
aoqi@0:   if (is_loop_head()) st->print(" lphd");
aoqi@0:   if (is_irreducible_entry()) st->print(" irred");
aoqi@0:   if (_jsrs->size() > 0) { st->print("/");  _jsrs->print_on(st); }
aoqi@0:   if (is_backedge_copy())  st->print("/backedge_copy");
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::Block::print_on
aoqi@0: void ciTypeFlow::Block::print_on(outputStream* st) const {
aoqi@0:   if ((Verbose || WizardMode) && (limit() >= 0)) {
aoqi@0:     // Don't print 'dummy' blocks (i.e. blocks with limit() '-1')
aoqi@0:     outer()->method()->print_codes_on(start(), limit(), st);
aoqi@0:   }
aoqi@0:   st->print_cr("  ====================================================  ");
aoqi@0:   st->print ("  ");
aoqi@0:   print_value_on(st);
aoqi@0:   st->print(" Stored locals: "); def_locals()->print_on(st, outer()->method()->max_locals()); tty->cr();
aoqi@0:   if (loop() && loop()->parent() != NULL) {
aoqi@0:     st->print(" loops:");
aoqi@0:     Loop* lp = loop();
aoqi@0:     do {
aoqi@0:       st->print(" %d<-%d", lp->head()->pre_order(),lp->tail()->pre_order());
aoqi@0:       if (lp->is_irreducible()) st->print("(ir)");
aoqi@0:       lp = lp->parent();
aoqi@0:     } while (lp->parent() != NULL);
aoqi@0:   }
aoqi@0:   st->cr();
aoqi@0:   _state->print_on(st);
aoqi@0:   if (_successors == NULL) {
aoqi@0:     st->print_cr("  No successor information");
aoqi@0:   } else {
aoqi@0:     int num_successors = _successors->length();
aoqi@0:     st->print_cr("  Successors : %d", num_successors);
aoqi@0:     for (int i = 0; i < num_successors; i++) {
aoqi@0:       Block* successor = _successors->at(i);
aoqi@0:       st->print("    ");
aoqi@0:       successor->print_value_on(st);
aoqi@0:       st->cr();
aoqi@0:     }
aoqi@0:   }
aoqi@0:   if (_exceptions == NULL) {
aoqi@0:     st->print_cr("  No exception information");
aoqi@0:   } else {
aoqi@0:     int num_exceptions = _exceptions->length();
aoqi@0:     st->print_cr("  Exceptions : %d", num_exceptions);
aoqi@0:     for (int i = 0; i < num_exceptions; i++) {
aoqi@0:       Block* exc_succ = _exceptions->at(i);
aoqi@0:       ciInstanceKlass* exc_klass = _exc_klasses->at(i);
aoqi@0:       st->print("    ");
aoqi@0:       exc_succ->print_value_on(st);
aoqi@0:       st->print(" -- ");
aoqi@0:       exc_klass->name()->print_symbol_on(st);
aoqi@0:       st->cr();
aoqi@0:     }
aoqi@0:   }
aoqi@0:   if (has_trap()) {
aoqi@0:     st->print_cr("  Traps on %d with trap index %d", trap_bci(), trap_index());
aoqi@0:   }
aoqi@0:   st->print_cr("  ====================================================  ");
aoqi@0: }
aoqi@0: #endif
aoqi@0: 
aoqi@0: #ifndef PRODUCT
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::LocalSet::print_on
aoqi@0: void ciTypeFlow::LocalSet::print_on(outputStream* st, int limit) const {
aoqi@0:   st->print("{");
aoqi@0:   for (int i = 0; i < max; i++) {
aoqi@0:     if (test(i)) st->print(" %d", i);
aoqi@0:   }
aoqi@0:   if (limit > max) {
aoqi@0:     st->print(" %d..%d ", max, limit);
aoqi@0:   }
aoqi@0:   st->print(" }");
aoqi@0: }
aoqi@0: #endif
aoqi@0: 
aoqi@0: // ciTypeFlow
aoqi@0: //
aoqi@0: // This is a pass over the bytecodes which computes the following:
aoqi@0: //   basic block structure
aoqi@0: //   interpreter type-states (a la the verifier)
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::ciTypeFlow
aoqi@0: ciTypeFlow::ciTypeFlow(ciEnv* env, ciMethod* method, int osr_bci) {
aoqi@0:   _env = env;
aoqi@0:   _method = method;
aoqi@0:   _methodBlocks = method->get_method_blocks();
aoqi@0:   _max_locals = method->max_locals();
aoqi@0:   _max_stack = method->max_stack();
aoqi@0:   _code_size = method->code_size();
aoqi@0:   _has_irreducible_entry = false;
aoqi@0:   _osr_bci = osr_bci;
aoqi@0:   _failure_reason = NULL;
aoqi@0:   assert(0 <= start_bci() && start_bci() < code_size() , err_msg("correct osr_bci argument: 0 <= %d < %d", start_bci(), code_size()));
aoqi@0:   _work_list = NULL;
aoqi@0: 
aoqi@0:   _ciblock_count = _methodBlocks->num_blocks();
aoqi@0:   _idx_to_blocklist = NEW_ARENA_ARRAY(arena(), GrowableArray<Block*>*, _ciblock_count);
aoqi@0:   for (int i = 0; i < _ciblock_count; i++) {
aoqi@0:     _idx_to_blocklist[i] = NULL;
aoqi@0:   }
aoqi@0:   _block_map = NULL;  // until all blocks are seen
aoqi@0:   _jsr_count = 0;
aoqi@0:   _jsr_records = NULL;
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::work_list_next
aoqi@0: //
aoqi@0: // Get the next basic block from our work list.
aoqi@0: ciTypeFlow::Block* ciTypeFlow::work_list_next() {
aoqi@0:   assert(!work_list_empty(), "work list must not be empty");
aoqi@0:   Block* next_block = _work_list;
aoqi@0:   _work_list = next_block->next();
aoqi@0:   next_block->set_next(NULL);
aoqi@0:   next_block->set_on_work_list(false);
aoqi@0:   return next_block;
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::add_to_work_list
aoqi@0: //
aoqi@0: // Add a basic block to our work list.
aoqi@0: // List is sorted by decreasing postorder sort (same as increasing RPO)
aoqi@0: void ciTypeFlow::add_to_work_list(ciTypeFlow::Block* block) {
aoqi@0:   assert(!block->is_on_work_list(), "must not already be on work list");
aoqi@0: 
aoqi@0:   if (CITraceTypeFlow) {
aoqi@0:     tty->print(">> Adding block ");
aoqi@0:     block->print_value_on(tty);
aoqi@0:     tty->print_cr(" to the work list : ");
aoqi@0:   }
aoqi@0: 
aoqi@0:   block->set_on_work_list(true);
aoqi@0: 
aoqi@0:   // decreasing post order sort
aoqi@0: 
aoqi@0:   Block* prev = NULL;
aoqi@0:   Block* current = _work_list;
aoqi@0:   int po = block->post_order();
aoqi@0:   while (current != NULL) {
aoqi@0:     if (!current->has_post_order() || po > current->post_order())
aoqi@0:       break;
aoqi@0:     prev = current;
aoqi@0:     current = current->next();
aoqi@0:   }
aoqi@0:   if (prev == NULL) {
aoqi@0:     block->set_next(_work_list);
aoqi@0:     _work_list = block;
aoqi@0:   } else {
aoqi@0:     block->set_next(current);
aoqi@0:     prev->set_next(block);
aoqi@0:   }
aoqi@0: 
aoqi@0:   if (CITraceTypeFlow) {
aoqi@0:     tty->cr();
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::block_at
aoqi@0: //
aoqi@0: // Return the block beginning at bci which has a JsrSet compatible
aoqi@0: // with jsrs.
aoqi@0: ciTypeFlow::Block* ciTypeFlow::block_at(int bci, ciTypeFlow::JsrSet* jsrs, CreateOption option) {
aoqi@0:   // First find the right ciBlock.
aoqi@0:   if (CITraceTypeFlow) {
aoqi@0:     tty->print(">> Requesting block for %d/", bci);
aoqi@0:     jsrs->print_on(tty);
aoqi@0:     tty->cr();
aoqi@0:   }
aoqi@0: 
aoqi@0:   ciBlock* ciblk = _methodBlocks->block_containing(bci);
aoqi@0:   assert(ciblk->start_bci() == bci, "bad ciBlock boundaries");
aoqi@0:   Block* block = get_block_for(ciblk->index(), jsrs, option);
aoqi@0: 
aoqi@0:   assert(block == NULL? (option == no_create): block->is_backedge_copy() == (option == create_backedge_copy), "create option consistent with result");
aoqi@0: 
aoqi@0:   if (CITraceTypeFlow) {
aoqi@0:     if (block != NULL) {
aoqi@0:       tty->print(">> Found block ");
aoqi@0:       block->print_value_on(tty);
aoqi@0:       tty->cr();
aoqi@0:     } else {
aoqi@0:       tty->print_cr(">> No such block.");
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   return block;
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::make_jsr_record
aoqi@0: //
aoqi@0: // Make a JsrRecord for a given (entry, return) pair, if such a record
aoqi@0: // does not already exist.
aoqi@0: ciTypeFlow::JsrRecord* ciTypeFlow::make_jsr_record(int entry_address,
aoqi@0:                                                    int return_address) {
aoqi@0:   if (_jsr_records == NULL) {
aoqi@0:     _jsr_records = new (arena()) GrowableArray<JsrRecord*>(arena(),
aoqi@0:                                                            _jsr_count,
aoqi@0:                                                            0,
aoqi@0:                                                            NULL);
aoqi@0:   }
aoqi@0:   JsrRecord* record = NULL;
aoqi@0:   int len = _jsr_records->length();
aoqi@0:   for (int i = 0; i < len; i++) {
aoqi@0:     JsrRecord* record = _jsr_records->at(i);
aoqi@0:     if (record->entry_address() == entry_address &&
aoqi@0:         record->return_address() == return_address) {
aoqi@0:       return record;
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   record = new (arena()) JsrRecord(entry_address, return_address);
aoqi@0:   _jsr_records->append(record);
aoqi@0:   return record;
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::flow_exceptions
aoqi@0: //
aoqi@0: // Merge the current state into all exceptional successors at the
aoqi@0: // current point in the code.
aoqi@0: void ciTypeFlow::flow_exceptions(GrowableArray<ciTypeFlow::Block*>* exceptions,
aoqi@0:                                  GrowableArray<ciInstanceKlass*>* exc_klasses,
aoqi@0:                                  ciTypeFlow::StateVector* state) {
aoqi@0:   int len = exceptions->length();
aoqi@0:   assert(exc_klasses->length() == len, "must have same length");
aoqi@0:   for (int i = 0; i < len; i++) {
aoqi@0:     Block* block = exceptions->at(i);
aoqi@0:     ciInstanceKlass* exception_klass = exc_klasses->at(i);
aoqi@0: 
aoqi@0:     if (!exception_klass->is_loaded()) {
aoqi@0:       // Do not compile any code for unloaded exception types.
aoqi@0:       // Following compiler passes are responsible for doing this also.
aoqi@0:       continue;
aoqi@0:     }
aoqi@0: 
aoqi@0:     if (block->meet_exception(exception_klass, state)) {
aoqi@0:       // Block was modified and has PO.  Add it to the work list.
aoqi@0:       if (block->has_post_order() &&
aoqi@0:           !block->is_on_work_list()) {
aoqi@0:         add_to_work_list(block);
aoqi@0:       }
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::flow_successors
aoqi@0: //
aoqi@0: // Merge the current state into all successors at the current point
aoqi@0: // in the code.
aoqi@0: void ciTypeFlow::flow_successors(GrowableArray<ciTypeFlow::Block*>* successors,
aoqi@0:                                  ciTypeFlow::StateVector* state) {
aoqi@0:   int len = successors->length();
aoqi@0:   for (int i = 0; i < len; i++) {
aoqi@0:     Block* block = successors->at(i);
aoqi@0:     if (block->meet(state)) {
aoqi@0:       // Block was modified and has PO.  Add it to the work list.
aoqi@0:       if (block->has_post_order() &&
aoqi@0:           !block->is_on_work_list()) {
aoqi@0:         add_to_work_list(block);
aoqi@0:       }
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::can_trap
aoqi@0: //
aoqi@0: // Tells if a given instruction is able to generate an exception edge.
aoqi@0: bool ciTypeFlow::can_trap(ciBytecodeStream& str) {
aoqi@0:   // Cf. GenerateOopMap::do_exception_edge.
aoqi@0:   if (!Bytecodes::can_trap(str.cur_bc()))  return false;
aoqi@0: 
aoqi@0:   switch (str.cur_bc()) {
aoqi@0:     // %%% FIXME: ldc of Class can generate an exception
aoqi@0:     case Bytecodes::_ldc:
aoqi@0:     case Bytecodes::_ldc_w:
aoqi@0:     case Bytecodes::_ldc2_w:
aoqi@0:     case Bytecodes::_aload_0:
aoqi@0:       // These bytecodes can trap for rewriting.  We need to assume that
aoqi@0:       // they do not throw exceptions to make the monitor analysis work.
aoqi@0:       return false;
aoqi@0: 
aoqi@0:     case Bytecodes::_ireturn:
aoqi@0:     case Bytecodes::_lreturn:
aoqi@0:     case Bytecodes::_freturn:
aoqi@0:     case Bytecodes::_dreturn:
aoqi@0:     case Bytecodes::_areturn:
aoqi@0:     case Bytecodes::_return:
aoqi@0:       // We can assume the monitor stack is empty in this analysis.
aoqi@0:       return false;
aoqi@0: 
aoqi@0:     case Bytecodes::_monitorexit:
aoqi@0:       // We can assume monitors are matched in this analysis.
aoqi@0:       return false;
aoqi@0:   }
aoqi@0: 
aoqi@0:   return true;
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::clone_loop_heads
aoqi@0: //
aoqi@0: // Clone the loop heads
aoqi@0: bool ciTypeFlow::clone_loop_heads(Loop* lp, StateVector* temp_vector, JsrSet* temp_set) {
aoqi@0:   bool rslt = false;
aoqi@0:   for (PreorderLoops iter(loop_tree_root()); !iter.done(); iter.next()) {
aoqi@0:     lp = iter.current();
aoqi@0:     Block* head = lp->head();
aoqi@0:     if (lp == loop_tree_root() ||
aoqi@0:         lp->is_irreducible() ||
aoqi@0:         !head->is_clonable_exit(lp))
aoqi@0:       continue;
aoqi@0: 
aoqi@0:     // Avoid BoxLock merge.
aoqi@0:     if (EliminateNestedLocks && head->has_monitorenter())
aoqi@0:       continue;
aoqi@0: 
aoqi@0:     // check not already cloned
aoqi@0:     if (head->backedge_copy_count() != 0)
aoqi@0:       continue;
aoqi@0: 
aoqi@0:     // Don't clone head of OSR loop to get correct types in start block.
aoqi@0:     if (is_osr_flow() && head->start() == start_bci())
aoqi@0:       continue;
aoqi@0: 
aoqi@0:     // check _no_ shared head below us
aoqi@0:     Loop* ch;
aoqi@0:     for (ch = lp->child(); ch != NULL && ch->head() != head; ch = ch->sibling());
aoqi@0:     if (ch != NULL)
aoqi@0:       continue;
aoqi@0: 
aoqi@0:     // Clone head
aoqi@0:     Block* new_head = head->looping_succ(lp);
aoqi@0:     Block* clone = clone_loop_head(lp, temp_vector, temp_set);
aoqi@0:     // Update lp's info
aoqi@0:     clone->set_loop(lp);
aoqi@0:     lp->set_head(new_head);
aoqi@0:     lp->set_tail(clone);
aoqi@0:     // And move original head into outer loop
aoqi@0:     head->set_loop(lp->parent());
aoqi@0: 
aoqi@0:     rslt = true;
aoqi@0:   }
aoqi@0:   return rslt;
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::clone_loop_head
aoqi@0: //
aoqi@0: // Clone lp's head and replace tail's successors with clone.
aoqi@0: //
aoqi@0: //  |
aoqi@0: //  v
aoqi@0: // head <-> body
aoqi@0: //  |
aoqi@0: //  v
aoqi@0: // exit
aoqi@0: //
aoqi@0: // new_head
aoqi@0: //
aoqi@0: //  |
aoqi@0: //  v
aoqi@0: // head ----------\
aoqi@0: //  |             |
aoqi@0: //  |             v
aoqi@0: //  |  clone <-> body
aoqi@0: //  |    |
aoqi@0: //  | /--/
aoqi@0: //  | |
aoqi@0: //  v v
aoqi@0: // exit
aoqi@0: //
aoqi@0: ciTypeFlow::Block* ciTypeFlow::clone_loop_head(Loop* lp, StateVector* temp_vector, JsrSet* temp_set) {
aoqi@0:   Block* head = lp->head();
aoqi@0:   Block* tail = lp->tail();
aoqi@0:   if (CITraceTypeFlow) {
aoqi@0:     tty->print(">> Requesting clone of loop head "); head->print_value_on(tty);
aoqi@0:     tty->print("  for predecessor ");                tail->print_value_on(tty);
aoqi@0:     tty->cr();
aoqi@0:   }
aoqi@0:   Block* clone = block_at(head->start(), head->jsrs(), create_backedge_copy);
aoqi@0:   assert(clone->backedge_copy_count() == 1, "one backedge copy for all back edges");
aoqi@0: 
aoqi@0:   assert(!clone->has_pre_order(), "just created");
aoqi@0:   clone->set_next_pre_order();
aoqi@0: 
aoqi@0:   // Insert clone after (orig) tail in reverse post order
aoqi@0:   clone->set_rpo_next(tail->rpo_next());
aoqi@0:   tail->set_rpo_next(clone);
aoqi@0: 
aoqi@0:   // tail->head becomes tail->clone
aoqi@0:   for (SuccIter iter(tail); !iter.done(); iter.next()) {
aoqi@0:     if (iter.succ() == head) {
aoqi@0:       iter.set_succ(clone);
aoqi@0:     }
aoqi@0:   }
aoqi@0:   flow_block(tail, temp_vector, temp_set);
aoqi@0:   if (head == tail) {
aoqi@0:     // For self-loops, clone->head becomes clone->clone
aoqi@0:     flow_block(clone, temp_vector, temp_set);
aoqi@0:     for (SuccIter iter(clone); !iter.done(); iter.next()) {
aoqi@0:       if (iter.succ() == head) {
aoqi@0:         iter.set_succ(clone);
aoqi@0:         break;
aoqi@0:       }
aoqi@0:     }
aoqi@0:   }
aoqi@0:   flow_block(clone, temp_vector, temp_set);
aoqi@0: 
aoqi@0:   return clone;
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::flow_block
aoqi@0: //
aoqi@0: // Interpret the effects of the bytecodes on the incoming state
aoqi@0: // vector of a basic block.  Push the changed state to succeeding
aoqi@0: // basic blocks.
aoqi@0: void ciTypeFlow::flow_block(ciTypeFlow::Block* block,
aoqi@0:                             ciTypeFlow::StateVector* state,
aoqi@0:                             ciTypeFlow::JsrSet* jsrs) {
aoqi@0:   if (CITraceTypeFlow) {
aoqi@0:     tty->print("\n>> ANALYZING BLOCK : ");
aoqi@0:     tty->cr();
aoqi@0:     block->print_on(tty);
aoqi@0:   }
aoqi@0:   assert(block->has_pre_order(), "pre-order is assigned before 1st flow");
aoqi@0: 
aoqi@0:   int start = block->start();
aoqi@0:   int limit = block->limit();
aoqi@0:   int control = block->control();
aoqi@0:   if (control != ciBlock::fall_through_bci) {
aoqi@0:     limit = control;
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Grab the state from the current block.
aoqi@0:   block->copy_state_into(state);
aoqi@0:   state->def_locals()->clear();
aoqi@0: 
aoqi@0:   GrowableArray<Block*>*           exceptions = block->exceptions();
aoqi@0:   GrowableArray<ciInstanceKlass*>* exc_klasses = block->exc_klasses();
aoqi@0:   bool has_exceptions = exceptions->length() > 0;
aoqi@0: 
aoqi@0:   bool exceptions_used = false;
aoqi@0: 
aoqi@0:   ciBytecodeStream str(method());
aoqi@0:   str.reset_to_bci(start);
aoqi@0:   Bytecodes::Code code;
aoqi@0:   while ((code = str.next()) != ciBytecodeStream::EOBC() &&
aoqi@0:          str.cur_bci() < limit) {
aoqi@0:     // Check for exceptional control flow from this point.
aoqi@0:     if (has_exceptions && can_trap(str)) {
aoqi@0:       flow_exceptions(exceptions, exc_klasses, state);
aoqi@0:       exceptions_used = true;
aoqi@0:     }
aoqi@0:     // Apply the effects of the current bytecode to our state.
aoqi@0:     bool res = state->apply_one_bytecode(&str);
aoqi@0: 
aoqi@0:     // Watch for bailouts.
aoqi@0:     if (failing())  return;
aoqi@0: 
aoqi@0:     if (str.cur_bc() == Bytecodes::_monitorenter) {
aoqi@0:       block->set_has_monitorenter();
aoqi@0:     }
aoqi@0: 
aoqi@0:     if (res) {
aoqi@0: 
aoqi@0:       // We have encountered a trap.  Record it in this block.
aoqi@0:       block->set_trap(state->trap_bci(), state->trap_index());
aoqi@0: 
aoqi@0:       if (CITraceTypeFlow) {
aoqi@0:         tty->print_cr(">> Found trap");
aoqi@0:         block->print_on(tty);
aoqi@0:       }
aoqi@0: 
aoqi@0:       // Save set of locals defined in this block
aoqi@0:       block->def_locals()->add(state->def_locals());
aoqi@0: 
aoqi@0:       // Record (no) successors.
aoqi@0:       block->successors(&str, state, jsrs);
aoqi@0: 
aoqi@0:       assert(!has_exceptions || exceptions_used, "Not removing exceptions");
aoqi@0: 
aoqi@0:       // Discontinue interpretation of this Block.
aoqi@0:       return;
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   GrowableArray<Block*>* successors = NULL;
aoqi@0:   if (control != ciBlock::fall_through_bci) {
aoqi@0:     // Check for exceptional control flow from this point.
aoqi@0:     if (has_exceptions && can_trap(str)) {
aoqi@0:       flow_exceptions(exceptions, exc_klasses, state);
aoqi@0:       exceptions_used = true;
aoqi@0:     }
aoqi@0: 
aoqi@0:     // Fix the JsrSet to reflect effect of the bytecode.
aoqi@0:     block->copy_jsrs_into(jsrs);
aoqi@0:     jsrs->apply_control(this, &str, state);
aoqi@0: 
aoqi@0:     // Find successor edges based on old state and new JsrSet.
aoqi@0:     successors = block->successors(&str, state, jsrs);
aoqi@0: 
aoqi@0:     // Apply the control changes to the state.
aoqi@0:     state->apply_one_bytecode(&str);
aoqi@0:   } else {
aoqi@0:     // Fall through control
aoqi@0:     successors = block->successors(&str, NULL, NULL);
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Save set of locals defined in this block
aoqi@0:   block->def_locals()->add(state->def_locals());
aoqi@0: 
aoqi@0:   // Remove untaken exception paths
aoqi@0:   if (!exceptions_used)
aoqi@0:     exceptions->clear();
aoqi@0: 
aoqi@0:   // Pass our state to successors.
aoqi@0:   flow_successors(successors, state);
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::PostOrderLoops::next
aoqi@0: //
aoqi@0: // Advance to next loop tree using a postorder, left-to-right traversal.
aoqi@0: void ciTypeFlow::PostorderLoops::next() {
aoqi@0:   assert(!done(), "must not be done.");
aoqi@0:   if (_current->sibling() != NULL) {
aoqi@0:     _current = _current->sibling();
aoqi@0:     while (_current->child() != NULL) {
aoqi@0:       _current = _current->child();
aoqi@0:     }
aoqi@0:   } else {
aoqi@0:     _current = _current->parent();
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::PreOrderLoops::next
aoqi@0: //
aoqi@0: // Advance to next loop tree using a preorder, left-to-right traversal.
aoqi@0: void ciTypeFlow::PreorderLoops::next() {
aoqi@0:   assert(!done(), "must not be done.");
aoqi@0:   if (_current->child() != NULL) {
aoqi@0:     _current = _current->child();
aoqi@0:   } else if (_current->sibling() != NULL) {
aoqi@0:     _current = _current->sibling();
aoqi@0:   } else {
aoqi@0:     while (_current != _root && _current->sibling() == NULL) {
aoqi@0:       _current = _current->parent();
aoqi@0:     }
aoqi@0:     if (_current == _root) {
aoqi@0:       _current = NULL;
aoqi@0:       assert(done(), "must be done.");
aoqi@0:     } else {
aoqi@0:       assert(_current->sibling() != NULL, "must be more to do");
aoqi@0:       _current = _current->sibling();
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::Loop::sorted_merge
aoqi@0: //
aoqi@0: // Merge the branch lp into this branch, sorting on the loop head
aoqi@0: // pre_orders. Returns the leaf of the merged branch.
aoqi@0: // Child and sibling pointers will be setup later.
aoqi@0: // Sort is (looking from leaf towards the root)
aoqi@0: //  descending on primary key: loop head's pre_order, and
aoqi@0: //  ascending  on secondary key: loop tail's pre_order.
aoqi@0: ciTypeFlow::Loop* ciTypeFlow::Loop::sorted_merge(Loop* lp) {
aoqi@0:   Loop* leaf = this;
aoqi@0:   Loop* prev = NULL;
aoqi@0:   Loop* current = leaf;
aoqi@0:   while (lp != NULL) {
aoqi@0:     int lp_pre_order = lp->head()->pre_order();
aoqi@0:     // Find insertion point for "lp"
aoqi@0:     while (current != NULL) {
aoqi@0:       if (current == lp)
aoqi@0:         return leaf; // Already in list
aoqi@0:       if (current->head()->pre_order() < lp_pre_order)
aoqi@0:         break;
aoqi@0:       if (current->head()->pre_order() == lp_pre_order &&
aoqi@0:           current->tail()->pre_order() > lp->tail()->pre_order()) {
aoqi@0:         break;
aoqi@0:       }
aoqi@0:       prev = current;
aoqi@0:       current = current->parent();
aoqi@0:     }
aoqi@0:     Loop* next_lp = lp->parent(); // Save future list of items to insert
aoqi@0:     // Insert lp before current
aoqi@0:     lp->set_parent(current);
aoqi@0:     if (prev != NULL) {
aoqi@0:       prev->set_parent(lp);
aoqi@0:     } else {
aoqi@0:       leaf = lp;
aoqi@0:     }
aoqi@0:     prev = lp;     // Inserted item is new prev[ious]
aoqi@0:     lp = next_lp;  // Next item to insert
aoqi@0:   }
aoqi@0:   return leaf;
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::build_loop_tree
aoqi@0: //
aoqi@0: // Incrementally build loop tree.
aoqi@0: void ciTypeFlow::build_loop_tree(Block* blk) {
aoqi@0:   assert(!blk->is_post_visited(), "precondition");
aoqi@0:   Loop* innermost = NULL; // merge of loop tree branches over all successors
aoqi@0: 
aoqi@0:   for (SuccIter iter(blk); !iter.done(); iter.next()) {
aoqi@0:     Loop*  lp   = NULL;
aoqi@0:     Block* succ = iter.succ();
aoqi@0:     if (!succ->is_post_visited()) {
aoqi@0:       // Found backedge since predecessor post visited, but successor is not
aoqi@0:       assert(succ->pre_order() <= blk->pre_order(), "should be backedge");
aoqi@0: 
aoqi@0:       // Create a LoopNode to mark this loop.
aoqi@0:       lp = new (arena()) Loop(succ, blk);
aoqi@0:       if (succ->loop() == NULL)
aoqi@0:         succ->set_loop(lp);
aoqi@0:       // succ->loop will be updated to innermost loop on a later call, when blk==succ
aoqi@0: 
aoqi@0:     } else {  // Nested loop
aoqi@0:       lp = succ->loop();
aoqi@0: 
aoqi@0:       // If succ is loop head, find outer loop.
aoqi@0:       while (lp != NULL && lp->head() == succ) {
aoqi@0:         lp = lp->parent();
aoqi@0:       }
aoqi@0:       if (lp == NULL) {
aoqi@0:         // Infinite loop, it's parent is the root
aoqi@0:         lp = loop_tree_root();
aoqi@0:       }
aoqi@0:     }
aoqi@0: 
aoqi@0:     // Check for irreducible loop.
aoqi@0:     // Successor has already been visited. If the successor's loop head
aoqi@0:     // has already been post-visited, then this is another entry into the loop.
aoqi@0:     while (lp->head()->is_post_visited() && lp != loop_tree_root()) {
aoqi@0:       _has_irreducible_entry = true;
aoqi@0:       lp->set_irreducible(succ);
aoqi@0:       if (!succ->is_on_work_list()) {
aoqi@0:         // Assume irreducible entries need more data flow
aoqi@0:         add_to_work_list(succ);
aoqi@0:       }
aoqi@0:       Loop* plp = lp->parent();
aoqi@0:       if (plp == NULL) {
aoqi@0:         // This only happens for some irreducible cases.  The parent
aoqi@0:         // will be updated during a later pass.
aoqi@0:         break;
aoqi@0:       }
aoqi@0:       lp = plp;
aoqi@0:     }
aoqi@0: 
aoqi@0:     // Merge loop tree branch for all successors.
aoqi@0:     innermost = innermost == NULL ? lp : innermost->sorted_merge(lp);
aoqi@0: 
aoqi@0:   } // end loop
aoqi@0: 
aoqi@0:   if (innermost == NULL) {
aoqi@0:     assert(blk->successors()->length() == 0, "CFG exit");
aoqi@0:     blk->set_loop(loop_tree_root());
aoqi@0:   } else if (innermost->head() == blk) {
aoqi@0:     // If loop header, complete the tree pointers
aoqi@0:     if (blk->loop() != innermost) {
aoqi@0: #ifdef ASSERT
aoqi@0:       assert(blk->loop()->head() == innermost->head(), "same head");
aoqi@0:       Loop* dl;
aoqi@0:       for (dl = innermost; dl != NULL && dl != blk->loop(); dl = dl->parent());
aoqi@0:       assert(dl == blk->loop(), "blk->loop() already in innermost list");
aoqi@0: #endif
aoqi@0:       blk->set_loop(innermost);
aoqi@0:     }
aoqi@0:     innermost->def_locals()->add(blk->def_locals());
aoqi@0:     Loop* l = innermost;
aoqi@0:     Loop* p = l->parent();
aoqi@0:     while (p && l->head() == blk) {
aoqi@0:       l->set_sibling(p->child());  // Put self on parents 'next child'
aoqi@0:       p->set_child(l);             // Make self the first child of parent
aoqi@0:       p->def_locals()->add(l->def_locals());
aoqi@0:       l = p;                       // Walk up the parent chain
aoqi@0:       p = l->parent();
aoqi@0:     }
aoqi@0:   } else {
aoqi@0:     blk->set_loop(innermost);
aoqi@0:     innermost->def_locals()->add(blk->def_locals());
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::Loop::contains
aoqi@0: //
aoqi@0: // Returns true if lp is nested loop.
aoqi@0: bool ciTypeFlow::Loop::contains(ciTypeFlow::Loop* lp) const {
aoqi@0:   assert(lp != NULL, "");
aoqi@0:   if (this == lp || head() == lp->head()) return true;
aoqi@0:   int depth1 = depth();
aoqi@0:   int depth2 = lp->depth();
aoqi@0:   if (depth1 > depth2)
aoqi@0:     return false;
aoqi@0:   while (depth1 < depth2) {
aoqi@0:     depth2--;
aoqi@0:     lp = lp->parent();
aoqi@0:   }
aoqi@0:   return this == lp;
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::Loop::depth
aoqi@0: //
aoqi@0: // Loop depth
aoqi@0: int ciTypeFlow::Loop::depth() const {
aoqi@0:   int dp = 0;
aoqi@0:   for (Loop* lp = this->parent(); lp != NULL; lp = lp->parent())
aoqi@0:     dp++;
aoqi@0:   return dp;
aoqi@0: }
aoqi@0: 
aoqi@0: #ifndef PRODUCT
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::Loop::print
aoqi@0: void ciTypeFlow::Loop::print(outputStream* st, int indent) const {
aoqi@0:   for (int i = 0; i < indent; i++) st->print(" ");
aoqi@0:   st->print("%d<-%d %s",
aoqi@0:             is_root() ? 0 : this->head()->pre_order(),
aoqi@0:             is_root() ? 0 : this->tail()->pre_order(),
aoqi@0:             is_irreducible()?" irr":"");
aoqi@0:   st->print(" defs: ");
aoqi@0:   def_locals()->print_on(st, _head->outer()->method()->max_locals());
aoqi@0:   st->cr();
aoqi@0:   for (Loop* ch = child(); ch != NULL; ch = ch->sibling())
aoqi@0:     ch->print(st, indent+2);
aoqi@0: }
aoqi@0: #endif
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::df_flow_types
aoqi@0: //
aoqi@0: // Perform the depth first type flow analysis. Helper for flow_types.
aoqi@0: void ciTypeFlow::df_flow_types(Block* start,
aoqi@0:                                bool do_flow,
aoqi@0:                                StateVector* temp_vector,
aoqi@0:                                JsrSet* temp_set) {
aoqi@0:   int dft_len = 100;
aoqi@0:   GrowableArray<Block*> stk(dft_len);
aoqi@0: 
aoqi@0:   ciBlock* dummy = _methodBlocks->make_dummy_block();
aoqi@0:   JsrSet* root_set = new JsrSet(NULL, 0);
aoqi@0:   Block* root_head = new (arena()) Block(this, dummy, root_set);
aoqi@0:   Block* root_tail = new (arena()) Block(this, dummy, root_set);
aoqi@0:   root_head->set_pre_order(0);
aoqi@0:   root_head->set_post_order(0);
aoqi@0:   root_tail->set_pre_order(max_jint);
aoqi@0:   root_tail->set_post_order(max_jint);
aoqi@0:   set_loop_tree_root(new (arena()) Loop(root_head, root_tail));
aoqi@0: 
aoqi@0:   stk.push(start);
aoqi@0: 
aoqi@0:   _next_pre_order = 0;  // initialize pre_order counter
aoqi@0:   _rpo_list = NULL;
aoqi@0:   int next_po = 0;      // initialize post_order counter
aoqi@0: 
aoqi@0:   // Compute RPO and the control flow graph
aoqi@0:   int size;
aoqi@0:   while ((size = stk.length()) > 0) {
aoqi@0:     Block* blk = stk.top(); // Leave node on stack
aoqi@0:     if (!blk->is_visited()) {
aoqi@0:       // forward arc in graph
aoqi@0:       assert (!blk->has_pre_order(), "");
aoqi@0:       blk->set_next_pre_order();
aoqi@0: 
vlivanov@7385:       if (_next_pre_order >= (int)Compile::current()->max_node_limit() / 2) {
aoqi@0:         // Too many basic blocks.  Bail out.
aoqi@0:         // This can happen when try/finally constructs are nested to depth N,
aoqi@0:         // and there is O(2**N) cloning of jsr bodies.  See bug 4697245!
aoqi@0:         // "MaxNodeLimit / 2" is used because probably the parser will
aoqi@0:         // generate at least twice that many nodes and bail out.
aoqi@0:         record_failure("too many basic blocks");
aoqi@0:         return;
aoqi@0:       }
aoqi@0:       if (do_flow) {
aoqi@0:         flow_block(blk, temp_vector, temp_set);
aoqi@0:         if (failing()) return; // Watch for bailouts.
aoqi@0:       }
aoqi@0:     } else if (!blk->is_post_visited()) {
aoqi@0:       // cross or back arc
aoqi@0:       for (SuccIter iter(blk); !iter.done(); iter.next()) {
aoqi@0:         Block* succ = iter.succ();
aoqi@0:         if (!succ->is_visited()) {
aoqi@0:           stk.push(succ);
aoqi@0:         }
aoqi@0:       }
aoqi@0:       if (stk.length() == size) {
aoqi@0:         // There were no additional children, post visit node now
aoqi@0:         stk.pop(); // Remove node from stack
aoqi@0: 
aoqi@0:         build_loop_tree(blk);
aoqi@0:         blk->set_post_order(next_po++);   // Assign post order
aoqi@0:         prepend_to_rpo_list(blk);
aoqi@0:         assert(blk->is_post_visited(), "");
aoqi@0: 
aoqi@0:         if (blk->is_loop_head() && !blk->is_on_work_list()) {
aoqi@0:           // Assume loop heads need more data flow
aoqi@0:           add_to_work_list(blk);
aoqi@0:         }
aoqi@0:       }
aoqi@0:     } else {
aoqi@0:       stk.pop(); // Remove post-visited node from stack
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::flow_types
aoqi@0: //
aoqi@0: // Perform the type flow analysis, creating and cloning Blocks as
aoqi@0: // necessary.
aoqi@0: void ciTypeFlow::flow_types() {
aoqi@0:   ResourceMark rm;
aoqi@0:   StateVector* temp_vector = new StateVector(this);
aoqi@0:   JsrSet* temp_set = new JsrSet(NULL, 16);
aoqi@0: 
aoqi@0:   // Create the method entry block.
aoqi@0:   Block* start = block_at(start_bci(), temp_set);
aoqi@0: 
aoqi@0:   // Load the initial state into it.
aoqi@0:   const StateVector* start_state = get_start_state();
aoqi@0:   if (failing())  return;
aoqi@0:   start->meet(start_state);
aoqi@0: 
aoqi@0:   // Depth first visit
aoqi@0:   df_flow_types(start, true /*do flow*/, temp_vector, temp_set);
aoqi@0: 
aoqi@0:   if (failing())  return;
aoqi@0:   assert(_rpo_list == start, "must be start");
aoqi@0: 
aoqi@0:   // Any loops found?
aoqi@0:   if (loop_tree_root()->child() != NULL &&
aoqi@0:       env()->comp_level() >= CompLevel_full_optimization) {
aoqi@0:       // Loop optimizations are not performed on Tier1 compiles.
aoqi@0: 
aoqi@0:     bool changed = clone_loop_heads(loop_tree_root(), temp_vector, temp_set);
aoqi@0: 
aoqi@0:     // If some loop heads were cloned, recompute postorder and loop tree
aoqi@0:     if (changed) {
aoqi@0:       loop_tree_root()->set_child(NULL);
aoqi@0:       for (Block* blk = _rpo_list; blk != NULL;) {
aoqi@0:         Block* next = blk->rpo_next();
aoqi@0:         blk->df_init();
aoqi@0:         blk = next;
aoqi@0:       }
aoqi@0:       df_flow_types(start, false /*no flow*/, temp_vector, temp_set);
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   if (CITraceTypeFlow) {
aoqi@0:     tty->print_cr("\nLoop tree");
aoqi@0:     loop_tree_root()->print();
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Continue flow analysis until fixed point reached
aoqi@0: 
aoqi@0:   debug_only(int max_block = _next_pre_order;)
aoqi@0: 
aoqi@0:   while (!work_list_empty()) {
aoqi@0:     Block* blk = work_list_next();
aoqi@0:     assert (blk->has_post_order(), "post order assigned above");
aoqi@0: 
aoqi@0:     flow_block(blk, temp_vector, temp_set);
aoqi@0: 
aoqi@0:     assert (max_block == _next_pre_order, "no new blocks");
aoqi@0:     assert (!failing(), "no more bailouts");
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::map_blocks
aoqi@0: //
aoqi@0: // Create the block map, which indexes blocks in reverse post-order.
aoqi@0: void ciTypeFlow::map_blocks() {
aoqi@0:   assert(_block_map == NULL, "single initialization");
aoqi@0:   int block_ct = _next_pre_order;
aoqi@0:   _block_map = NEW_ARENA_ARRAY(arena(), Block*, block_ct);
aoqi@0:   assert(block_ct == block_count(), "");
aoqi@0: 
aoqi@0:   Block* blk = _rpo_list;
aoqi@0:   for (int m = 0; m < block_ct; m++) {
aoqi@0:     int rpo = blk->rpo();
aoqi@0:     assert(rpo == m, "should be sequential");
aoqi@0:     _block_map[rpo] = blk;
aoqi@0:     blk = blk->rpo_next();
aoqi@0:   }
aoqi@0:   assert(blk == NULL, "should be done");
aoqi@0: 
aoqi@0:   for (int j = 0; j < block_ct; j++) {
aoqi@0:     assert(_block_map[j] != NULL, "must not drop any blocks");
aoqi@0:     Block* block = _block_map[j];
aoqi@0:     // Remove dead blocks from successor lists:
aoqi@0:     for (int e = 0; e <= 1; e++) {
aoqi@0:       GrowableArray<Block*>* l = e? block->exceptions(): block->successors();
aoqi@0:       for (int k = 0; k < l->length(); k++) {
aoqi@0:         Block* s = l->at(k);
aoqi@0:         if (!s->has_post_order()) {
aoqi@0:           if (CITraceTypeFlow) {
aoqi@0:             tty->print("Removing dead %s successor of #%d: ", (e? "exceptional":  "normal"), block->pre_order());
aoqi@0:             s->print_value_on(tty);
aoqi@0:             tty->cr();
aoqi@0:           }
aoqi@0:           l->remove(s);
aoqi@0:           --k;
aoqi@0:         }
aoqi@0:       }
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::get_block_for
aoqi@0: //
aoqi@0: // Find a block with this ciBlock which has a compatible JsrSet.
aoqi@0: // If no such block exists, create it, unless the option is no_create.
aoqi@0: // If the option is create_backedge_copy, always create a fresh backedge copy.
aoqi@0: ciTypeFlow::Block* ciTypeFlow::get_block_for(int ciBlockIndex, ciTypeFlow::JsrSet* jsrs, CreateOption option) {
aoqi@0:   Arena* a = arena();
aoqi@0:   GrowableArray<Block*>* blocks = _idx_to_blocklist[ciBlockIndex];
aoqi@0:   if (blocks == NULL) {
aoqi@0:     // Query only?
aoqi@0:     if (option == no_create)  return NULL;
aoqi@0: 
aoqi@0:     // Allocate the growable array.
aoqi@0:     blocks = new (a) GrowableArray<Block*>(a, 4, 0, NULL);
aoqi@0:     _idx_to_blocklist[ciBlockIndex] = blocks;
aoqi@0:   }
aoqi@0: 
aoqi@0:   if (option != create_backedge_copy) {
aoqi@0:     int len = blocks->length();
aoqi@0:     for (int i = 0; i < len; i++) {
aoqi@0:       Block* block = blocks->at(i);
aoqi@0:       if (!block->is_backedge_copy() && block->is_compatible_with(jsrs)) {
aoqi@0:         return block;
aoqi@0:       }
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Query only?
aoqi@0:   if (option == no_create)  return NULL;
aoqi@0: 
aoqi@0:   // We did not find a compatible block.  Create one.
aoqi@0:   Block* new_block = new (a) Block(this, _methodBlocks->block(ciBlockIndex), jsrs);
aoqi@0:   if (option == create_backedge_copy)  new_block->set_backedge_copy(true);
aoqi@0:   blocks->append(new_block);
aoqi@0:   return new_block;
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::backedge_copy_count
aoqi@0: //
aoqi@0: int ciTypeFlow::backedge_copy_count(int ciBlockIndex, ciTypeFlow::JsrSet* jsrs) const {
aoqi@0:   GrowableArray<Block*>* blocks = _idx_to_blocklist[ciBlockIndex];
aoqi@0: 
aoqi@0:   if (blocks == NULL) {
aoqi@0:     return 0;
aoqi@0:   }
aoqi@0: 
aoqi@0:   int count = 0;
aoqi@0:   int len = blocks->length();
aoqi@0:   for (int i = 0; i < len; i++) {
aoqi@0:     Block* block = blocks->at(i);
aoqi@0:     if (block->is_backedge_copy() && block->is_compatible_with(jsrs)) {
aoqi@0:       count++;
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   return count;
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::do_flow
aoqi@0: //
aoqi@0: // Perform type inference flow analysis.
aoqi@0: void ciTypeFlow::do_flow() {
aoqi@0:   if (CITraceTypeFlow) {
aoqi@0:     tty->print_cr("\nPerforming flow analysis on method");
aoqi@0:     method()->print();
aoqi@0:     if (is_osr_flow())  tty->print(" at OSR bci %d", start_bci());
aoqi@0:     tty->cr();
aoqi@0:     method()->print_codes();
aoqi@0:   }
aoqi@0:   if (CITraceTypeFlow) {
aoqi@0:     tty->print_cr("Initial CI Blocks");
aoqi@0:     print_on(tty);
aoqi@0:   }
aoqi@0:   flow_types();
aoqi@0:   // Watch for bailouts.
aoqi@0:   if (failing()) {
aoqi@0:     return;
aoqi@0:   }
aoqi@0: 
aoqi@0:   map_blocks();
aoqi@0: 
aoqi@0:   if (CIPrintTypeFlow || CITraceTypeFlow) {
aoqi@0:     rpo_print_on(tty);
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::record_failure()
aoqi@0: // The ciTypeFlow object keeps track of failure reasons separately from the ciEnv.
aoqi@0: // This is required because there is not a 1-1 relation between the ciEnv and
aoqi@0: // the TypeFlow passes within a compilation task.  For example, if the compiler
aoqi@0: // is considering inlining a method, it will request a TypeFlow.  If that fails,
aoqi@0: // the compilation as a whole may continue without the inlining.  Some TypeFlow
aoqi@0: // requests are not optional; if they fail the requestor is responsible for
aoqi@0: // copying the failure reason up to the ciEnv.  (See Parse::Parse.)
aoqi@0: void ciTypeFlow::record_failure(const char* reason) {
aoqi@0:   if (env()->log() != NULL) {
aoqi@0:     env()->log()->elem("failure reason='%s' phase='typeflow'", reason);
aoqi@0:   }
aoqi@0:   if (_failure_reason == NULL) {
aoqi@0:     // Record the first failure reason.
aoqi@0:     _failure_reason = reason;
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: #ifndef PRODUCT
aoqi@0: // ------------------------------------------------------------------
aoqi@0: // ciTypeFlow::print_on
aoqi@0: void ciTypeFlow::print_on(outputStream* st) const {
aoqi@0:   // Walk through CI blocks
aoqi@0:   st->print_cr("********************************************************");
aoqi@0:   st->print   ("TypeFlow for ");
aoqi@0:   method()->name()->print_symbol_on(st);
aoqi@0:   int limit_bci = code_size();
aoqi@0:   st->print_cr("  %d bytes", limit_bci);
aoqi@0:   ciMethodBlocks  *mblks = _methodBlocks;
aoqi@0:   ciBlock* current = NULL;
aoqi@0:   for (int bci = 0; bci < limit_bci; bci++) {
aoqi@0:     ciBlock* blk = mblks->block_containing(bci);
aoqi@0:     if (blk != NULL && blk != current) {
aoqi@0:       current = blk;
aoqi@0:       current->print_on(st);
aoqi@0: 
aoqi@0:       GrowableArray<Block*>* blocks = _idx_to_blocklist[blk->index()];
aoqi@0:       int num_blocks = (blocks == NULL) ? 0 : blocks->length();
aoqi@0: 
aoqi@0:       if (num_blocks == 0) {
aoqi@0:         st->print_cr("  No Blocks");
aoqi@0:       } else {
aoqi@0:         for (int i = 0; i < num_blocks; i++) {
aoqi@0:           Block* block = blocks->at(i);
aoqi@0:           block->print_on(st);
aoqi@0:         }
aoqi@0:       }
aoqi@0:       st->print_cr("--------------------------------------------------------");
aoqi@0:       st->cr();
aoqi@0:     }
aoqi@0:   }
aoqi@0:   st->print_cr("********************************************************");
aoqi@0:   st->cr();
aoqi@0: }
aoqi@0: 
aoqi@0: void ciTypeFlow::rpo_print_on(outputStream* st) const {
aoqi@0:   st->print_cr("********************************************************");
aoqi@0:   st->print   ("TypeFlow for ");
aoqi@0:   method()->name()->print_symbol_on(st);
aoqi@0:   int limit_bci = code_size();
aoqi@0:   st->print_cr("  %d bytes", limit_bci);
aoqi@0:   for (Block* blk = _rpo_list; blk != NULL; blk = blk->rpo_next()) {
aoqi@0:     blk->print_on(st);
aoqi@0:     st->print_cr("--------------------------------------------------------");
aoqi@0:     st->cr();
aoqi@0:   }
aoqi@0:   st->print_cr("********************************************************");
aoqi@0:   st->cr();
aoqi@0: }
aoqi@0: #endif