jdk8-mips64-public/hotspot: src/share/vm/c1/c1_Instruction.cpp@ff1a29907b6c (annotated)

src/share/vm/c1/c1_Instruction.cpp@ff1a29907b6c (annotated)

src/share/vm/c1/c1_Instruction.cpp

Mon, 31 Aug 2009 17:07:53 -0700

author: never
date: Mon, 31 Aug 2009 17:07:53 -0700
changeset 1388: ff1a29907b6c
parent 435: a61af66fc99e
child 1730: 3cf667df43ef
permissions: -rw-r--r--

6855215: Calculation error (NaN) after about 1500 calculations
Reviewed-by: kvn

 /*
  * Copyright 1999-2006 Sun Microsystems, Inc.  All Rights Reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  * CA 95054 USA or visit www.sun.com if you need additional information or
  * have any questions.
  *
  */
 #include "incls/_precompiled.incl"
 #include "incls/_c1_Instruction.cpp.incl"
 // Implementation of Instruction
 int Instruction::_next_id = 0;
 #ifdef ASSERT
 void Instruction::create_hi_word() {
   assert(type()->is_double_word() && _hi_word == NULL, "only double word has high word");
   _hi_word = new HiWord(this);
 }
 #endif
 Instruction::Condition Instruction::mirror(Condition cond) {
   switch (cond) {
     case eql: return eql;
     case neq: return neq;
     case lss: return gtr;
     case leq: return geq;
     case gtr: return lss;
     case geq: return leq;
   }
   ShouldNotReachHere();
   return eql;
 }
 Instruction::Condition Instruction::negate(Condition cond) {
   switch (cond) {
     case eql: return neq;
     case neq: return eql;
     case lss: return geq;
     case leq: return gtr;
     case gtr: return leq;
     case geq: return lss;
   }
   ShouldNotReachHere();
   return eql;
 }
 Instruction* Instruction::prev(BlockBegin* block) {
   Instruction* p = NULL;
   Instruction* q = block;
   while (q != this) {
     assert(q != NULL, "this is not in the block's instruction list");
     p = q; q = q->next();
   }
   return p;
 }
 #ifndef PRODUCT
 void Instruction::print() {
   InstructionPrinter ip;
   print(ip);
 }
 void Instruction::print_line() {
   InstructionPrinter ip;
   ip.print_line(this);
 }
 void Instruction::print(InstructionPrinter& ip) {
   ip.print_head();
   ip.print_line(this);
   tty->cr();
 }
 #endif // PRODUCT
 // perform constant and interval tests on index value
 bool AccessIndexed::compute_needs_range_check() {
   Constant* clength = length()->as_Constant();
   Constant* cindex = index()->as_Constant();
   if (clength && cindex) {
     IntConstant* l = clength->type()->as_IntConstant();
     IntConstant* i = cindex->type()->as_IntConstant();
     if (l && i && i->value() < l->value() && i->value() >= 0) {
       return false;
     }
   }
   return true;
 }
 ciType* LoadIndexed::exact_type() const {
   ciType* array_type = array()->exact_type();
   if (array_type == NULL) {
     return NULL;
   }
   assert(array_type->is_array_klass(), "what else?");
   ciArrayKlass* ak = (ciArrayKlass*)array_type;
   if (ak->element_type()->is_instance_klass()) {
     ciInstanceKlass* ik = (ciInstanceKlass*)ak->element_type();
     if (ik->is_loaded() && ik->is_final()) {
       return ik;
     }
   }
   return NULL;
 }
 ciType* LoadIndexed::declared_type() const {
   ciType* array_type = array()->declared_type();
   if (array_type == NULL) {
     return NULL;
   }
   assert(array_type->is_array_klass(), "what else?");
   ciArrayKlass* ak = (ciArrayKlass*)array_type;
   return ak->element_type();
 }
 ciType* LoadField::declared_type() const {
   return field()->type();
 }
 ciType* LoadField::exact_type() const {
   ciType* type = declared_type();
   // for primitive arrays, the declared type is the exact type
   if (type->is_type_array_klass()) {
     return type;
   }
   if (type->is_instance_klass()) {
     ciInstanceKlass* ik = (ciInstanceKlass*)type;
     if (ik->is_loaded() && ik->is_final()) {
       return type;
     }
   }
   return NULL;
 }
 ciType* NewTypeArray::exact_type() const {
   return ciTypeArrayKlass::make(elt_type());
 }
 ciType* NewObjectArray::exact_type() const {
   return ciObjArrayKlass::make(klass());
 }
 ciType* NewInstance::exact_type() const {
   return klass();
 }
 ciType* CheckCast::declared_type() const {
   return klass();
 }
 ciType* CheckCast::exact_type() const {
   if (klass()->is_instance_klass()) {
     ciInstanceKlass* ik = (ciInstanceKlass*)klass();
     if (ik->is_loaded() && ik->is_final()) {
       return ik;
     }
   }
   return NULL;
 }
 void ArithmeticOp::other_values_do(void f(Value*)) {
   if (lock_stack() != NULL) lock_stack()->values_do(f);
 }
 void NullCheck::other_values_do(void f(Value*)) {
   lock_stack()->values_do(f);
 }
 void AccessArray::other_values_do(void f(Value*)) {
   if (lock_stack() != NULL) lock_stack()->values_do(f);
 }
 // Implementation of AccessField
 void AccessField::other_values_do(void f(Value*)) {
   if (state_before() != NULL) state_before()->values_do(f);
   if (lock_stack() != NULL) lock_stack()->values_do(f);
 }
 // Implementation of StoreIndexed
 IRScope* StoreIndexed::scope() const {
   return lock_stack()->scope();
 }
 // Implementation of ArithmeticOp
 bool ArithmeticOp::is_commutative() const {
   switch (op()) {
     case Bytecodes::_iadd: // fall through
     case Bytecodes::_ladd: // fall through
     case Bytecodes::_fadd: // fall through
     case Bytecodes::_dadd: // fall through
     case Bytecodes::_imul: // fall through
     case Bytecodes::_lmul: // fall through
     case Bytecodes::_fmul: // fall through
     case Bytecodes::_dmul: return true;
   }
   return false;
 }
 bool ArithmeticOp::can_trap() const {
   switch (op()) {
     case Bytecodes::_idiv: // fall through
     case Bytecodes::_ldiv: // fall through
     case Bytecodes::_irem: // fall through
     case Bytecodes::_lrem: return true;
   }
   return false;
 }
 // Implementation of LogicOp
 bool LogicOp::is_commutative() const {
 #ifdef ASSERT
   switch (op()) {
     case Bytecodes::_iand: // fall through
     case Bytecodes::_land: // fall through
     case Bytecodes::_ior : // fall through
     case Bytecodes::_lor : // fall through
     case Bytecodes::_ixor: // fall through
     case Bytecodes::_lxor: break;
     default              : ShouldNotReachHere();
   }
 #endif
   // all LogicOps are commutative
   return true;
 }
 // Implementation of CompareOp
 void CompareOp::other_values_do(void f(Value*)) {
   if (state_before() != NULL) state_before()->values_do(f);
 }
 // Implementation of IfOp
 bool IfOp::is_commutative() const {
   return cond() == eql || cond() == neq;
 }
 // Implementation of StateSplit
 void StateSplit::substitute(BlockList& list, BlockBegin* old_block, BlockBegin* new_block) {
   NOT_PRODUCT(bool assigned = false;)
   for (int i = 0; i < list.length(); i++) {
     BlockBegin** b = list.adr_at(i);
     if (*b == old_block) {
       *b = new_block;
       NOT_PRODUCT(assigned = true;)
     }
   }
   assert(assigned == true, "should have assigned at least once");
 }
 IRScope* StateSplit::scope() const {
   return _state->scope();
 }
 void StateSplit::state_values_do(void f(Value*)) {
   if (state() != NULL) state()->values_do(f);
 }
 void BlockBegin::state_values_do(void f(Value*)) {
   StateSplit::state_values_do(f);
   if (is_set(BlockBegin::exception_entry_flag)) {
     for (int i = 0; i < number_of_exception_states(); i++) {
       exception_state_at(i)->values_do(f);
     }
   }
 }
 void MonitorEnter::state_values_do(void f(Value*)) {
   StateSplit::state_values_do(f);
   _lock_stack_before->values_do(f);
 }
 void Intrinsic::state_values_do(void f(Value*)) {
   StateSplit::state_values_do(f);
   if (lock_stack() != NULL) lock_stack()->values_do(f);
 }
 // Implementation of Invoke
 Invoke::Invoke(Bytecodes::Code code, ValueType* result_type, Value recv, Values* args,
                int vtable_index, ciMethod* target)
   : StateSplit(result_type)
   , _code(code)
   , _recv(recv)
   , _args(args)
   , _vtable_index(vtable_index)
   , _target(target)
 {
   set_flag(TargetIsLoadedFlag,   target->is_loaded());
   set_flag(TargetIsFinalFlag,    target_is_loaded() && target->is_final_method());
   set_flag(TargetIsStrictfpFlag, target_is_loaded() && target->is_strict());
   assert(args != NULL, "args must exist");
 #ifdef ASSERT
   values_do(assert_value);
 #endif // ASSERT
   // provide an initial guess of signature size.
   _signature = new BasicTypeList(number_of_arguments() + (has_receiver() ? 1 : 0));
   if (has_receiver()) {
     _signature->append(as_BasicType(receiver()->type()));
   }
   for (int i = 0; i < number_of_arguments(); i++) {
     ValueType* t = argument_at(i)->type();
     BasicType bt = as_BasicType(t);
     _signature->append(bt);
   }
 }
 // Implementation of Contant
 intx Constant::hash() const {
   if (_state == NULL) {
     switch (type()->tag()) {
     case intTag:
       return HASH2(name(), type()->as_IntConstant()->value());
     case longTag:
       {
         jlong temp = type()->as_LongConstant()->value();
         return HASH3(name(), high(temp), low(temp));
       }
     case floatTag:
       return HASH2(name(), jint_cast(type()->as_FloatConstant()->value()));
     case doubleTag:
       {
         jlong temp = jlong_cast(type()->as_DoubleConstant()->value());
         return HASH3(name(), high(temp), low(temp));
       }
     case objectTag:
       assert(type()->as_ObjectType()->is_loaded(), "can't handle unloaded values");
       return HASH2(name(), type()->as_ObjectType()->constant_value());
     }
   }
   return 0;
 }
 bool Constant::is_equal(Value v) const {
   if (v->as_Constant() == NULL) return false;
   switch (type()->tag()) {
     case intTag:
       {
         IntConstant* t1 =    type()->as_IntConstant();
         IntConstant* t2 = v->type()->as_IntConstant();
         return (t1 != NULL && t2 != NULL &&
                 t1->value() == t2->value());
       }
     case longTag:
       {
         LongConstant* t1 =    type()->as_LongConstant();
         LongConstant* t2 = v->type()->as_LongConstant();
         return (t1 != NULL && t2 != NULL &&
                 t1->value() == t2->value());
       }
     case floatTag:
       {
         FloatConstant* t1 =    type()->as_FloatConstant();
         FloatConstant* t2 = v->type()->as_FloatConstant();
         return (t1 != NULL && t2 != NULL &&
                 jint_cast(t1->value()) == jint_cast(t2->value()));
       }
     case doubleTag:
       {
         DoubleConstant* t1 =    type()->as_DoubleConstant();
         DoubleConstant* t2 = v->type()->as_DoubleConstant();
         return (t1 != NULL && t2 != NULL &&
                 jlong_cast(t1->value()) == jlong_cast(t2->value()));
       }
     case objectTag:
       {
         ObjectType* t1 =    type()->as_ObjectType();
         ObjectType* t2 = v->type()->as_ObjectType();
         return (t1 != NULL && t2 != NULL &&
                 t1->is_loaded() && t2->is_loaded() &&
                 t1->constant_value() == t2->constant_value());
       }
   }
   return false;
 }
 BlockBegin* Constant::compare(Instruction::Condition cond, Value right,
                               BlockBegin* true_sux, BlockBegin* false_sux) {
   Constant* rc = right->as_Constant();
   // other is not a constant
   if (rc == NULL) return NULL;
   ValueType* lt = type();
   ValueType* rt = rc->type();
   // different types
   if (lt->base() != rt->base()) return NULL;
   switch (lt->tag()) {
   case intTag: {
     int x = lt->as_IntConstant()->value();
     int y = rt->as_IntConstant()->value();
     switch (cond) {
     case If::eql: return x == y ? true_sux : false_sux;
     case If::neq: return x != y ? true_sux : false_sux;
     case If::lss: return x <  y ? true_sux : false_sux;
     case If::leq: return x <= y ? true_sux : false_sux;
     case If::gtr: return x >  y ? true_sux : false_sux;
     case If::geq: return x >= y ? true_sux : false_sux;
     }
     break;
   }
   case longTag: {
     jlong x = lt->as_LongConstant()->value();
     jlong y = rt->as_LongConstant()->value();
     switch (cond) {
     case If::eql: return x == y ? true_sux : false_sux;
     case If::neq: return x != y ? true_sux : false_sux;
     case If::lss: return x <  y ? true_sux : false_sux;
     case If::leq: return x <= y ? true_sux : false_sux;
     case If::gtr: return x >  y ? true_sux : false_sux;
     case If::geq: return x >= y ? true_sux : false_sux;
     }
     break;
   }
   case objectTag: {
     ciObject* xvalue = lt->as_ObjectType()->constant_value();
     ciObject* yvalue = rt->as_ObjectType()->constant_value();
     assert(xvalue != NULL && yvalue != NULL, "not constants");
     if (xvalue->is_loaded() && yvalue->is_loaded()) {
       switch (cond) {
       case If::eql: return xvalue == yvalue ? true_sux : false_sux;
       case If::neq: return xvalue != yvalue ? true_sux : false_sux;
       }
     }
     break;
   }
   }
   return NULL;
 }
 void Constant::other_values_do(void f(Value*)) {
   if (state() != NULL) state()->values_do(f);
 }
 // Implementation of NewArray
 void NewArray::other_values_do(void f(Value*)) {
   if (state_before() != NULL) state_before()->values_do(f);
 }
 // Implementation of TypeCheck
 void TypeCheck::other_values_do(void f(Value*)) {
   if (state_before() != NULL) state_before()->values_do(f);
 }
 // Implementation of BlockBegin
 int BlockBegin::_next_block_id = 0;
 void BlockBegin::set_end(BlockEnd* end) {
   assert(end != NULL, "should not reset block end to NULL");
   BlockEnd* old_end = _end;
   if (end == old_end) {
     return;
   }
   // Must make the predecessors/successors match up with the
   // BlockEnd's notion.
   int i, n;
   if (old_end != NULL) {
     // disconnect from the old end
     old_end->set_begin(NULL);
     // disconnect this block from it's current successors
     for (i = 0; i < _successors.length(); i++) {
       _successors.at(i)->remove_predecessor(this);
     }
   }
   _end = end;
   _successors.clear();
   // Now reset successors list based on BlockEnd
   n = end->number_of_sux();
   for (i = 0; i < n; i++) {
     BlockBegin* sux = end->sux_at(i);
     _successors.append(sux);
     sux->_predecessors.append(this);
   }
   _end->set_begin(this);
 }
 void BlockBegin::disconnect_edge(BlockBegin* from, BlockBegin* to) {
   // disconnect any edges between from and to
 #ifndef PRODUCT
   if (PrintIR && Verbose) {
     tty->print_cr("Disconnected edge B%d -> B%d", from->block_id(), to->block_id());
   }
 #endif
   for (int s = 0; s < from->number_of_sux();) {
     BlockBegin* sux = from->sux_at(s);
     if (sux == to) {
       int index = sux->_predecessors.index_of(from);
       if (index >= 0) {
         sux->_predecessors.remove_at(index);
       }
       from->_successors.remove_at(s);
     } else {
       s++;
     }
   }
 }
 void BlockBegin::disconnect_from_graph() {
   // disconnect this block from all other blocks
   for (int p = 0; p < number_of_preds(); p++) {
     pred_at(p)->remove_successor(this);
   }
   for (int s = 0; s < number_of_sux(); s++) {
     sux_at(s)->remove_predecessor(this);
   }
 }
 void BlockBegin::substitute_sux(BlockBegin* old_sux, BlockBegin* new_sux) {
   // modify predecessors before substituting successors
   for (int i = 0; i < number_of_sux(); i++) {
     if (sux_at(i) == old_sux) {
       // remove old predecessor before adding new predecessor
       // otherwise there is a dead predecessor in the list
       new_sux->remove_predecessor(old_sux);
       new_sux->add_predecessor(this);
     }
   }
   old_sux->remove_predecessor(this);
   end()->substitute_sux(old_sux, new_sux);
 }
 // In general it is not possible to calculate a value for the field "depth_first_number"
 // of the inserted block, without recomputing the values of the other blocks
 // in the CFG. Therefore the value of "depth_first_number" in BlockBegin becomes meaningless.
 BlockBegin* BlockBegin::insert_block_between(BlockBegin* sux) {
   // Try to make the bci close to a block with a single pred or sux,
   // since this make the block layout algorithm work better.
   int bci = -1;
   if (sux->number_of_preds() == 1) {
     bci = sux->bci();
   } else {
     bci = end()->bci();
   }
   BlockBegin* new_sux = new BlockBegin(bci);
   // mark this block (special treatment when block order is computed)
   new_sux->set(critical_edge_split_flag);
   // This goto is not a safepoint.
   Goto* e = new Goto(sux, false);
   new_sux->set_next(e, bci);
   new_sux->set_end(e);
   // setup states
   ValueStack* s = end()->state();
   new_sux->set_state(s->copy());
   e->set_state(s->copy());
   assert(new_sux->state()->locals_size() == s->locals_size(), "local size mismatch!");
   assert(new_sux->state()->stack_size() == s->stack_size(), "stack size mismatch!");
   assert(new_sux->state()->locks_size() == s->locks_size(), "locks size mismatch!");
   // link predecessor to new block
   end()->substitute_sux(sux, new_sux);
   // The ordering needs to be the same, so remove the link that the
   // set_end call above added and substitute the new_sux for this
   // block.
   sux->remove_predecessor(new_sux);
   // the successor could be the target of a switch so it might have
   // multiple copies of this predecessor, so substitute the new_sux
   // for the first and delete the rest.
   bool assigned = false;
   BlockList& list = sux->_predecessors;
   for (int i = 0; i < list.length(); i++) {
     BlockBegin** b = list.adr_at(i);
     if (*b == this) {
       if (assigned) {
         list.remove_at(i);
         // reprocess this index
         i--;
       } else {
         assigned = true;
         *b = new_sux;
       }
       // link the new block back to it's predecessors.
       new_sux->add_predecessor(this);
     }
   }
   assert(assigned == true, "should have assigned at least once");
   return new_sux;
 }
 void BlockBegin::remove_successor(BlockBegin* pred) {
   int idx;
   while ((idx = _successors.index_of(pred)) >= 0) {
     _successors.remove_at(idx);
   }
 }
 void BlockBegin::add_predecessor(BlockBegin* pred) {
   _predecessors.append(pred);
 }
 void BlockBegin::remove_predecessor(BlockBegin* pred) {
   int idx;
   while ((idx = _predecessors.index_of(pred)) >= 0) {
     _predecessors.remove_at(idx);
   }
 }
 void BlockBegin::add_exception_handler(BlockBegin* b) {
   assert(b != NULL && (b->is_set(exception_entry_flag)), "exception handler must exist");
   // add only if not in the list already
   if (!_exception_handlers.contains(b)) _exception_handlers.append(b);
 }
 int BlockBegin::add_exception_state(ValueStack* state) {
   assert(is_set(exception_entry_flag), "only for xhandlers");
   if (_exception_states == NULL) {
     _exception_states = new ValueStackStack(4);
   }
   _exception_states->append(state);
   return _exception_states->length() - 1;
 }
 void BlockBegin::iterate_preorder(boolArray& mark, BlockClosure* closure) {
   if (!mark.at(block_id())) {
     mark.at_put(block_id(), true);
     closure->block_do(this);
     BlockEnd* e = end(); // must do this after block_do because block_do may change it!
     { for (int i = number_of_exception_handlers() - 1; i >= 0; i--) exception_handler_at(i)->iterate_preorder(mark, closure); }
     { for (int i = e->number_of_sux            () - 1; i >= 0; i--) e->sux_at           (i)->iterate_preorder(mark, closure); }
   }
 }
 void BlockBegin::iterate_postorder(boolArray& mark, BlockClosure* closure) {
   if (!mark.at(block_id())) {
     mark.at_put(block_id(), true);
     BlockEnd* e = end();
     { for (int i = number_of_exception_handlers() - 1; i >= 0; i--) exception_handler_at(i)->iterate_postorder(mark, closure); }
     { for (int i = e->number_of_sux            () - 1; i >= 0; i--) e->sux_at           (i)->iterate_postorder(mark, closure); }
     closure->block_do(this);
   }
 }
 void BlockBegin::iterate_preorder(BlockClosure* closure) {
   boolArray mark(number_of_blocks(), false);
   iterate_preorder(mark, closure);
 }
 void BlockBegin::iterate_postorder(BlockClosure* closure) {
   boolArray mark(number_of_blocks(), false);
   iterate_postorder(mark, closure);
 }
 void BlockBegin::block_values_do(void f(Value*)) {
   for (Instruction* n = this; n != NULL; n = n->next()) n->values_do(f);
 }
 #ifndef PRODUCT
   #define TRACE_PHI(code) if (PrintPhiFunctions) { code; }
 #else
   #define TRACE_PHI(coce)
 #endif
 bool BlockBegin::try_merge(ValueStack* new_state) {
   TRACE_PHI(tty->print_cr("********** try_merge for block B%d", block_id()));
   // local variables used for state iteration
   int index;
   Value new_value, existing_value;
   ValueStack* existing_state = state();
   if (existing_state == NULL) {
     TRACE_PHI(tty->print_cr("first call of try_merge for this block"));
     if (is_set(BlockBegin::was_visited_flag)) {
       // this actually happens for complicated jsr/ret structures
       return false; // BAILOUT in caller
     }
     // copy state because it is altered
     new_state = new_state->copy();
     // Use method liveness to invalidate dead locals
     MethodLivenessResult liveness = new_state->scope()->method()->liveness_at_bci(bci());
     if (liveness.is_valid()) {
       assert((int)liveness.size() == new_state->locals_size(), "error in use of liveness");
       for_each_local_value(new_state, index, new_value) {
         if (!liveness.at(index) || new_value->type()->is_illegal()) {
           new_state->invalidate_local(index);
           TRACE_PHI(tty->print_cr("invalidating dead local %d", index));
         }
       }
     }
     if (is_set(BlockBegin::parser_loop_header_flag)) {
       TRACE_PHI(tty->print_cr("loop header block, initializing phi functions"));
       for_each_stack_value(new_state, index, new_value) {
         new_state->setup_phi_for_stack(this, index);
         TRACE_PHI(tty->print_cr("creating phi-function %c%d for stack %d", new_state->stack_at(index)->type()->tchar(), new_state->stack_at(index)->id(), index));
       }
       BitMap requires_phi_function = new_state->scope()->requires_phi_function();
       for_each_local_value(new_state, index, new_value) {
         bool requires_phi = requires_phi_function.at(index) || (new_value->type()->is_double_word() && requires_phi_function.at(index + 1));
         if (requires_phi || !SelectivePhiFunctions) {
           new_state->setup_phi_for_local(this, index);
           TRACE_PHI(tty->print_cr("creating phi-function %c%d for local %d", new_state->local_at(index)->type()->tchar(), new_state->local_at(index)->id(), index));
         }
       }
     }
     // initialize state of block
     set_state(new_state);
   } else if (existing_state->is_same_across_scopes(new_state)) {
     TRACE_PHI(tty->print_cr("exisiting state found"));
     // Inlining may cause the local state not to match up, so walk up
     // the new state until we get to the same scope as the
     // existing and then start processing from there.
     while (existing_state->scope() != new_state->scope()) {
       new_state = new_state->caller_state();
       assert(new_state != NULL, "could not match up scopes");
       assert(false, "check if this is necessary");
     }
     assert(existing_state->scope() == new_state->scope(), "not matching");
     assert(existing_state->locals_size() == new_state->locals_size(), "not matching");
     assert(existing_state->stack_size() == new_state->stack_size(), "not matching");
     if (is_set(BlockBegin::was_visited_flag)) {
       TRACE_PHI(tty->print_cr("loop header block, phis must be present"));
       if (!is_set(BlockBegin::parser_loop_header_flag)) {
         // this actually happens for complicated jsr/ret structures
         return false; // BAILOUT in caller
       }
       for_each_local_value(existing_state, index, existing_value) {
         Value new_value = new_state->local_at(index);
         if (new_value == NULL || new_value->type()->tag() != existing_value->type()->tag()) {
           // The old code invalidated the phi function here
           // Because dead locals are replaced with NULL, this is a very rare case now, so simply bail out
           return false; // BAILOUT in caller
         }
       }
 #ifdef ASSERT
       // check that all necessary phi functions are present
       for_each_stack_value(existing_state, index, existing_value) {
         assert(existing_value->as_Phi() != NULL && existing_value->as_Phi()->block() == this, "phi function required");
       }
       for_each_local_value(existing_state, index, existing_value) {
         assert(existing_value == new_state->local_at(index) || (existing_value->as_Phi() != NULL && existing_value->as_Phi()->as_Phi()->block() == this), "phi function required");
       }
 #endif
     } else {
       TRACE_PHI(tty->print_cr("creating phi functions on demand"));
       // create necessary phi functions for stack
       for_each_stack_value(existing_state, index, existing_value) {
         Value new_value = new_state->stack_at(index);
         Phi* existing_phi = existing_value->as_Phi();
         if (new_value != existing_value && (existing_phi == NULL || existing_phi->block() != this)) {
           existing_state->setup_phi_for_stack(this, index);
           TRACE_PHI(tty->print_cr("creating phi-function %c%d for stack %d", existing_state->stack_at(index)->type()->tchar(), existing_state->stack_at(index)->id(), index));
         }
       }
       // create necessary phi functions for locals
       for_each_local_value(existing_state, index, existing_value) {
         Value new_value = new_state->local_at(index);
         Phi* existing_phi = existing_value->as_Phi();
         if (new_value == NULL || new_value->type()->tag() != existing_value->type()->tag()) {
           existing_state->invalidate_local(index);
           TRACE_PHI(tty->print_cr("invalidating local %d because of type mismatch", index));
         } else if (new_value != existing_value && (existing_phi == NULL || existing_phi->block() != this)) {
           existing_state->setup_phi_for_local(this, index);
           TRACE_PHI(tty->print_cr("creating phi-function %c%d for local %d", existing_state->local_at(index)->type()->tchar(), existing_state->local_at(index)->id(), index));
         }
       }
     }
     assert(existing_state->caller_state() == new_state->caller_state(), "caller states must be equal");
   } else {
     assert(false, "stack or locks not matching (invalid bytecodes)");
     return false;
   }
   TRACE_PHI(tty->print_cr("********** try_merge for block B%d successful", block_id()));
   return true;
 }
 #ifndef PRODUCT
 void BlockBegin::print_block() {
   InstructionPrinter ip;
   print_block(ip, false);
 }
 void BlockBegin::print_block(InstructionPrinter& ip, bool live_only) {
   ip.print_instr(this); tty->cr();
   ip.print_stack(this->state()); tty->cr();
   ip.print_inline_level(this);
   ip.print_head();
   for (Instruction* n = next(); n != NULL; n = n->next()) {
     if (!live_only || n->is_pinned() || n->use_count() > 0) {
       ip.print_line(n);
     }
   }
   tty->cr();
 }
 #endif // PRODUCT
 // Implementation of BlockList
 void BlockList::iterate_forward (BlockClosure* closure) {
   const int l = length();
   for (int i = 0; i < l; i++) closure->block_do(at(i));
 }
 void BlockList::iterate_backward(BlockClosure* closure) {
   for (int i = length() - 1; i >= 0; i--) closure->block_do(at(i));
 }
 void BlockList::blocks_do(void f(BlockBegin*)) {
   for (int i = length() - 1; i >= 0; i--) f(at(i));
 }
 void BlockList::values_do(void f(Value*)) {
   for (int i = length() - 1; i >= 0; i--) at(i)->block_values_do(f);
 }
 #ifndef PRODUCT
 void BlockList::print(bool cfg_only, bool live_only) {
   InstructionPrinter ip;
   for (int i = 0; i < length(); i++) {
     BlockBegin* block = at(i);
     if (cfg_only) {
       ip.print_instr(block); tty->cr();
     } else {
       block->print_block(ip, live_only);
     }
   }
 }
 #endif // PRODUCT
 // Implementation of BlockEnd
 void BlockEnd::set_begin(BlockBegin* begin) {
   BlockList* sux = NULL;
   if (begin != NULL) {
     sux = begin->successors();
   } else if (_begin != NULL) {
     // copy our sux list
     BlockList* sux = new BlockList(_begin->number_of_sux());
     for (int i = 0; i < _begin->number_of_sux(); i++) {
       sux->append(_begin->sux_at(i));
     }
   }
   _sux = sux;
   _begin = begin;
 }
 void BlockEnd::substitute_sux(BlockBegin* old_sux, BlockBegin* new_sux) {
   substitute(*_sux, old_sux, new_sux);
 }
 void BlockEnd::other_values_do(void f(Value*)) {
   if (state_before() != NULL) state_before()->values_do(f);
 }
 // Implementation of Phi
 // Normal phi functions take their operands from the last instruction of the
 // predecessor. Special handling is needed for xhanlder entries because there
 // the state of arbitrary instructions are needed.
 Value Phi::operand_at(int i) const {
   ValueStack* state;
   if (_block->is_set(BlockBegin::exception_entry_flag)) {
     state = _block->exception_state_at(i);
   } else {
     state = _block->pred_at(i)->end()->state();
   }
   assert(state != NULL, "");
   if (is_local()) {
     return state->local_at(local_index());
   } else {
     return state->stack_at(stack_index());
   }
 }
 int Phi::operand_count() const {
   if (_block->is_set(BlockBegin::exception_entry_flag)) {
     return _block->number_of_exception_states();
   } else {
     return _block->number_of_preds();
   }
 }
 // Implementation of Throw
 void Throw::state_values_do(void f(Value*)) {
   BlockEnd::state_values_do(f);
 }

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/c1/c1_Instruction.cpp@ff1a29907b6c (annotated)

src/share/vm/c1/c1_Instruction.cpp