duke@435: /*
trims@1907:  * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
duke@435:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435:  *
duke@435:  * This code is free software; you can redistribute it and/or modify it
duke@435:  * under the terms of the GNU General Public License version 2 only, as
duke@435:  * published by the Free Software Foundation.
duke@435:  *
duke@435:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@435:  * version 2 for more details (a copy is included in the LICENSE file that
duke@435:  * accompanied this code).
duke@435:  *
duke@435:  * You should have received a copy of the GNU General Public License version
duke@435:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@435:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435:  *
trims@1907:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907:  * or visit www.oracle.com if you need additional information or have any
trims@1907:  * questions.
duke@435:  *
duke@435:  */
duke@435: 
duke@435: #include "incls/_precompiled.incl"
duke@435: #include "incls/_c1_Instruction.cpp.incl"
duke@435: 
duke@435: 
duke@435: // Implementation of Instruction
duke@435: 
duke@435: 
duke@435: int Instruction::_next_id = 0;
duke@435: 
duke@435: #ifdef ASSERT
duke@435: void Instruction::create_hi_word() {
duke@435:   assert(type()->is_double_word() && _hi_word == NULL, "only double word has high word");
duke@435:   _hi_word = new HiWord(this);
duke@435: }
duke@435: #endif
duke@435: 
duke@435: Instruction::Condition Instruction::mirror(Condition cond) {
duke@435:   switch (cond) {
duke@435:     case eql: return eql;
duke@435:     case neq: return neq;
duke@435:     case lss: return gtr;
duke@435:     case leq: return geq;
duke@435:     case gtr: return lss;
duke@435:     case geq: return leq;
duke@435:   }
duke@435:   ShouldNotReachHere();
duke@435:   return eql;
duke@435: }
duke@435: 
duke@435: 
duke@435: Instruction::Condition Instruction::negate(Condition cond) {
duke@435:   switch (cond) {
duke@435:     case eql: return neq;
duke@435:     case neq: return eql;
duke@435:     case lss: return geq;
duke@435:     case leq: return gtr;
duke@435:     case gtr: return leq;
duke@435:     case geq: return lss;
duke@435:   }
duke@435:   ShouldNotReachHere();
duke@435:   return eql;
duke@435: }
duke@435: 
duke@435: 
duke@435: Instruction* Instruction::prev(BlockBegin* block) {
duke@435:   Instruction* p = NULL;
duke@435:   Instruction* q = block;
duke@435:   while (q != this) {
duke@435:     assert(q != NULL, "this is not in the block's instruction list");
duke@435:     p = q; q = q->next();
duke@435:   }
duke@435:   return p;
duke@435: }
duke@435: 
duke@435: 
duke@435: #ifndef PRODUCT
duke@435: void Instruction::print() {
duke@435:   InstructionPrinter ip;
duke@435:   print(ip);
duke@435: }
duke@435: 
duke@435: 
duke@435: void Instruction::print_line() {
duke@435:   InstructionPrinter ip;
duke@435:   ip.print_line(this);
duke@435: }
duke@435: 
duke@435: 
duke@435: void Instruction::print(InstructionPrinter& ip) {
duke@435:   ip.print_head();
duke@435:   ip.print_line(this);
duke@435:   tty->cr();
duke@435: }
duke@435: #endif // PRODUCT
duke@435: 
duke@435: 
duke@435: // perform constant and interval tests on index value
duke@435: bool AccessIndexed::compute_needs_range_check() {
duke@435:   Constant* clength = length()->as_Constant();
duke@435:   Constant* cindex = index()->as_Constant();
duke@435:   if (clength && cindex) {
duke@435:     IntConstant* l = clength->type()->as_IntConstant();
duke@435:     IntConstant* i = cindex->type()->as_IntConstant();
duke@435:     if (l && i && i->value() < l->value() && i->value() >= 0) {
duke@435:       return false;
duke@435:     }
duke@435:   }
duke@435:   return true;
duke@435: }
duke@435: 
duke@435: 
duke@435: ciType* LoadIndexed::exact_type() const {
duke@435:   ciType* array_type = array()->exact_type();
duke@435:   if (array_type == NULL) {
duke@435:     return NULL;
duke@435:   }
duke@435:   assert(array_type->is_array_klass(), "what else?");
duke@435:   ciArrayKlass* ak = (ciArrayKlass*)array_type;
duke@435: 
duke@435:   if (ak->element_type()->is_instance_klass()) {
duke@435:     ciInstanceKlass* ik = (ciInstanceKlass*)ak->element_type();
duke@435:     if (ik->is_loaded() && ik->is_final()) {
duke@435:       return ik;
duke@435:     }
duke@435:   }
duke@435:   return NULL;
duke@435: }
duke@435: 
duke@435: 
duke@435: ciType* LoadIndexed::declared_type() const {
duke@435:   ciType* array_type = array()->declared_type();
duke@435:   if (array_type == NULL) {
duke@435:     return NULL;
duke@435:   }
duke@435:   assert(array_type->is_array_klass(), "what else?");
duke@435:   ciArrayKlass* ak = (ciArrayKlass*)array_type;
duke@435:   return ak->element_type();
duke@435: }
duke@435: 
duke@435: 
duke@435: ciType* LoadField::declared_type() const {
duke@435:   return field()->type();
duke@435: }
duke@435: 
duke@435: 
duke@435: ciType* LoadField::exact_type() const {
duke@435:   ciType* type = declared_type();
duke@435:   // for primitive arrays, the declared type is the exact type
duke@435:   if (type->is_type_array_klass()) {
duke@435:     return type;
duke@435:   }
duke@435:   if (type->is_instance_klass()) {
duke@435:     ciInstanceKlass* ik = (ciInstanceKlass*)type;
duke@435:     if (ik->is_loaded() && ik->is_final()) {
duke@435:       return type;
duke@435:     }
duke@435:   }
duke@435:   return NULL;
duke@435: }
duke@435: 
duke@435: 
duke@435: ciType* NewTypeArray::exact_type() const {
duke@435:   return ciTypeArrayKlass::make(elt_type());
duke@435: }
duke@435: 
duke@435: 
duke@435: ciType* NewObjectArray::exact_type() const {
duke@435:   return ciObjArrayKlass::make(klass());
duke@435: }
duke@435: 
duke@435: 
duke@435: ciType* NewInstance::exact_type() const {
duke@435:   return klass();
duke@435: }
duke@435: 
duke@435: 
duke@435: ciType* CheckCast::declared_type() const {
duke@435:   return klass();
duke@435: }
duke@435: 
duke@435: ciType* CheckCast::exact_type() const {
duke@435:   if (klass()->is_instance_klass()) {
duke@435:     ciInstanceKlass* ik = (ciInstanceKlass*)klass();
duke@435:     if (ik->is_loaded() && ik->is_final()) {
duke@435:       return ik;
duke@435:     }
duke@435:   }
duke@435:   return NULL;
duke@435: }
duke@435: 
duke@435: 
duke@435: void ArithmeticOp::other_values_do(void f(Value*)) {
duke@435:   if (lock_stack() != NULL) lock_stack()->values_do(f);
duke@435: }
duke@435: 
duke@435: void NullCheck::other_values_do(void f(Value*)) {
duke@435:   lock_stack()->values_do(f);
duke@435: }
duke@435: 
duke@435: void AccessArray::other_values_do(void f(Value*)) {
duke@435:   if (lock_stack() != NULL) lock_stack()->values_do(f);
duke@435: }
duke@435: 
duke@435: 
duke@435: // Implementation of AccessField
duke@435: 
duke@435: void AccessField::other_values_do(void f(Value*)) {
duke@435:   if (state_before() != NULL) state_before()->values_do(f);
duke@435:   if (lock_stack() != NULL) lock_stack()->values_do(f);
duke@435: }
duke@435: 
duke@435: 
duke@435: // Implementation of StoreIndexed
duke@435: 
duke@435: IRScope* StoreIndexed::scope() const {
duke@435:   return lock_stack()->scope();
duke@435: }
duke@435: 
duke@435: 
duke@435: // Implementation of ArithmeticOp
duke@435: 
duke@435: bool ArithmeticOp::is_commutative() const {
duke@435:   switch (op()) {
duke@435:     case Bytecodes::_iadd: // fall through
duke@435:     case Bytecodes::_ladd: // fall through
duke@435:     case Bytecodes::_fadd: // fall through
duke@435:     case Bytecodes::_dadd: // fall through
duke@435:     case Bytecodes::_imul: // fall through
duke@435:     case Bytecodes::_lmul: // fall through
duke@435:     case Bytecodes::_fmul: // fall through
duke@435:     case Bytecodes::_dmul: return true;
duke@435:   }
duke@435:   return false;
duke@435: }
duke@435: 
duke@435: 
duke@435: bool ArithmeticOp::can_trap() const {
duke@435:   switch (op()) {
duke@435:     case Bytecodes::_idiv: // fall through
duke@435:     case Bytecodes::_ldiv: // fall through
duke@435:     case Bytecodes::_irem: // fall through
duke@435:     case Bytecodes::_lrem: return true;
duke@435:   }
duke@435:   return false;
duke@435: }
duke@435: 
duke@435: 
duke@435: // Implementation of LogicOp
duke@435: 
duke@435: bool LogicOp::is_commutative() const {
duke@435: #ifdef ASSERT
duke@435:   switch (op()) {
duke@435:     case Bytecodes::_iand: // fall through
duke@435:     case Bytecodes::_land: // fall through
duke@435:     case Bytecodes::_ior : // fall through
duke@435:     case Bytecodes::_lor : // fall through
duke@435:     case Bytecodes::_ixor: // fall through
duke@435:     case Bytecodes::_lxor: break;
duke@435:     default              : ShouldNotReachHere();
duke@435:   }
duke@435: #endif
duke@435:   // all LogicOps are commutative
duke@435:   return true;
duke@435: }
duke@435: 
duke@435: 
duke@435: // Implementation of CompareOp
duke@435: 
duke@435: void CompareOp::other_values_do(void f(Value*)) {
duke@435:   if (state_before() != NULL) state_before()->values_do(f);
duke@435: }
duke@435: 
duke@435: 
duke@435: // Implementation of IfOp
duke@435: 
duke@435: bool IfOp::is_commutative() const {
duke@435:   return cond() == eql || cond() == neq;
duke@435: }
duke@435: 
duke@435: 
duke@435: // Implementation of StateSplit
duke@435: 
duke@435: void StateSplit::substitute(BlockList& list, BlockBegin* old_block, BlockBegin* new_block) {
duke@435:   NOT_PRODUCT(bool assigned = false;)
duke@435:   for (int i = 0; i < list.length(); i++) {
duke@435:     BlockBegin** b = list.adr_at(i);
duke@435:     if (*b == old_block) {
duke@435:       *b = new_block;
duke@435:       NOT_PRODUCT(assigned = true;)
duke@435:     }
duke@435:   }
duke@435:   assert(assigned == true, "should have assigned at least once");
duke@435: }
duke@435: 
duke@435: 
duke@435: IRScope* StateSplit::scope() const {
duke@435:   return _state->scope();
duke@435: }
duke@435: 
duke@435: 
duke@435: void StateSplit::state_values_do(void f(Value*)) {
duke@435:   if (state() != NULL) state()->values_do(f);
duke@435: }
duke@435: 
duke@435: 
duke@435: void BlockBegin::state_values_do(void f(Value*)) {
duke@435:   StateSplit::state_values_do(f);
duke@435: 
duke@435:   if (is_set(BlockBegin::exception_entry_flag)) {
duke@435:     for (int i = 0; i < number_of_exception_states(); i++) {
duke@435:       exception_state_at(i)->values_do(f);
duke@435:     }
duke@435:   }
duke@435: }
duke@435: 
duke@435: 
duke@435: void MonitorEnter::state_values_do(void f(Value*)) {
duke@435:   StateSplit::state_values_do(f);
duke@435:   _lock_stack_before->values_do(f);
duke@435: }
duke@435: 
duke@435: 
duke@435: void Intrinsic::state_values_do(void f(Value*)) {
duke@435:   StateSplit::state_values_do(f);
duke@435:   if (lock_stack() != NULL) lock_stack()->values_do(f);
duke@435: }
duke@435: 
duke@435: 
duke@435: // Implementation of Invoke
duke@435: 
duke@435: 
duke@435: Invoke::Invoke(Bytecodes::Code code, ValueType* result_type, Value recv, Values* args,
twisti@1730:                int vtable_index, ciMethod* target, ValueStack* state_before)
duke@435:   : StateSplit(result_type)
duke@435:   , _code(code)
duke@435:   , _recv(recv)
duke@435:   , _args(args)
duke@435:   , _vtable_index(vtable_index)
duke@435:   , _target(target)
twisti@1730:   , _state_before(state_before)
duke@435: {
duke@435:   set_flag(TargetIsLoadedFlag,   target->is_loaded());
duke@435:   set_flag(TargetIsFinalFlag,    target_is_loaded() && target->is_final_method());
duke@435:   set_flag(TargetIsStrictfpFlag, target_is_loaded() && target->is_strict());
duke@435: 
duke@435:   assert(args != NULL, "args must exist");
duke@435: #ifdef ASSERT
duke@435:   values_do(assert_value);
duke@435: #endif // ASSERT
duke@435: 
duke@435:   // provide an initial guess of signature size.
duke@435:   _signature = new BasicTypeList(number_of_arguments() + (has_receiver() ? 1 : 0));
duke@435:   if (has_receiver()) {
duke@435:     _signature->append(as_BasicType(receiver()->type()));
twisti@1730:   } else if (is_invokedynamic()) {
twisti@1730:     // Add the synthetic MethodHandle argument to the signature.
twisti@1730:     _signature->append(T_OBJECT);
duke@435:   }
duke@435:   for (int i = 0; i < number_of_arguments(); i++) {
duke@435:     ValueType* t = argument_at(i)->type();
duke@435:     BasicType bt = as_BasicType(t);
duke@435:     _signature->append(bt);
duke@435:   }
duke@435: }
duke@435: 
duke@435: 
twisti@1730: void Invoke::state_values_do(void f(Value*)) {
twisti@1730:   StateSplit::state_values_do(f);
twisti@1730:   if (state_before() != NULL) state_before()->values_do(f);
twisti@1730:   if (state()        != NULL) state()->values_do(f);
twisti@1730: }
twisti@1730: 
twisti@1730: 
duke@435: // Implementation of Contant
duke@435: intx Constant::hash() const {
duke@435:   if (_state == NULL) {
duke@435:     switch (type()->tag()) {
duke@435:     case intTag:
duke@435:       return HASH2(name(), type()->as_IntConstant()->value());
duke@435:     case longTag:
duke@435:       {
duke@435:         jlong temp = type()->as_LongConstant()->value();
duke@435:         return HASH3(name(), high(temp), low(temp));
duke@435:       }
duke@435:     case floatTag:
duke@435:       return HASH2(name(), jint_cast(type()->as_FloatConstant()->value()));
duke@435:     case doubleTag:
duke@435:       {
duke@435:         jlong temp = jlong_cast(type()->as_DoubleConstant()->value());
duke@435:         return HASH3(name(), high(temp), low(temp));
duke@435:       }
duke@435:     case objectTag:
duke@435:       assert(type()->as_ObjectType()->is_loaded(), "can't handle unloaded values");
duke@435:       return HASH2(name(), type()->as_ObjectType()->constant_value());
duke@435:     }
duke@435:   }
duke@435:   return 0;
duke@435: }
duke@435: 
duke@435: bool Constant::is_equal(Value v) const {
duke@435:   if (v->as_Constant() == NULL) return false;
duke@435: 
duke@435:   switch (type()->tag()) {
duke@435:     case intTag:
duke@435:       {
duke@435:         IntConstant* t1 =    type()->as_IntConstant();
duke@435:         IntConstant* t2 = v->type()->as_IntConstant();
duke@435:         return (t1 != NULL && t2 != NULL &&
duke@435:                 t1->value() == t2->value());
duke@435:       }
duke@435:     case longTag:
duke@435:       {
duke@435:         LongConstant* t1 =    type()->as_LongConstant();
duke@435:         LongConstant* t2 = v->type()->as_LongConstant();
duke@435:         return (t1 != NULL && t2 != NULL &&
duke@435:                 t1->value() == t2->value());
duke@435:       }
duke@435:     case floatTag:
duke@435:       {
duke@435:         FloatConstant* t1 =    type()->as_FloatConstant();
duke@435:         FloatConstant* t2 = v->type()->as_FloatConstant();
duke@435:         return (t1 != NULL && t2 != NULL &&
duke@435:                 jint_cast(t1->value()) == jint_cast(t2->value()));
duke@435:       }
duke@435:     case doubleTag:
duke@435:       {
duke@435:         DoubleConstant* t1 =    type()->as_DoubleConstant();
duke@435:         DoubleConstant* t2 = v->type()->as_DoubleConstant();
duke@435:         return (t1 != NULL && t2 != NULL &&
duke@435:                 jlong_cast(t1->value()) == jlong_cast(t2->value()));
duke@435:       }
duke@435:     case objectTag:
duke@435:       {
duke@435:         ObjectType* t1 =    type()->as_ObjectType();
duke@435:         ObjectType* t2 = v->type()->as_ObjectType();
duke@435:         return (t1 != NULL && t2 != NULL &&
duke@435:                 t1->is_loaded() && t2->is_loaded() &&
duke@435:                 t1->constant_value() == t2->constant_value());
duke@435:       }
duke@435:   }
duke@435:   return false;
duke@435: }
duke@435: 
duke@435: 
duke@435: BlockBegin* Constant::compare(Instruction::Condition cond, Value right,
duke@435:                               BlockBegin* true_sux, BlockBegin* false_sux) {
duke@435:   Constant* rc = right->as_Constant();
duke@435:   // other is not a constant
duke@435:   if (rc == NULL) return NULL;
duke@435: 
duke@435:   ValueType* lt = type();
duke@435:   ValueType* rt = rc->type();
duke@435:   // different types
duke@435:   if (lt->base() != rt->base()) return NULL;
duke@435:   switch (lt->tag()) {
duke@435:   case intTag: {
duke@435:     int x = lt->as_IntConstant()->value();
duke@435:     int y = rt->as_IntConstant()->value();
duke@435:     switch (cond) {
duke@435:     case If::eql: return x == y ? true_sux : false_sux;
duke@435:     case If::neq: return x != y ? true_sux : false_sux;
duke@435:     case If::lss: return x <  y ? true_sux : false_sux;
duke@435:     case If::leq: return x <= y ? true_sux : false_sux;
duke@435:     case If::gtr: return x >  y ? true_sux : false_sux;
duke@435:     case If::geq: return x >= y ? true_sux : false_sux;
duke@435:     }
duke@435:     break;
duke@435:   }
duke@435:   case longTag: {
duke@435:     jlong x = lt->as_LongConstant()->value();
duke@435:     jlong y = rt->as_LongConstant()->value();
duke@435:     switch (cond) {
duke@435:     case If::eql: return x == y ? true_sux : false_sux;
duke@435:     case If::neq: return x != y ? true_sux : false_sux;
duke@435:     case If::lss: return x <  y ? true_sux : false_sux;
duke@435:     case If::leq: return x <= y ? true_sux : false_sux;
duke@435:     case If::gtr: return x >  y ? true_sux : false_sux;
duke@435:     case If::geq: return x >= y ? true_sux : false_sux;
duke@435:     }
duke@435:     break;
duke@435:   }
duke@435:   case objectTag: {
duke@435:     ciObject* xvalue = lt->as_ObjectType()->constant_value();
duke@435:     ciObject* yvalue = rt->as_ObjectType()->constant_value();
duke@435:     assert(xvalue != NULL && yvalue != NULL, "not constants");
duke@435:     if (xvalue->is_loaded() && yvalue->is_loaded()) {
duke@435:       switch (cond) {
duke@435:       case If::eql: return xvalue == yvalue ? true_sux : false_sux;
duke@435:       case If::neq: return xvalue != yvalue ? true_sux : false_sux;
duke@435:       }
duke@435:     }
duke@435:     break;
duke@435:   }
duke@435:   }
duke@435:   return NULL;
duke@435: }
duke@435: 
duke@435: 
duke@435: void Constant::other_values_do(void f(Value*)) {
duke@435:   if (state() != NULL) state()->values_do(f);
duke@435: }
duke@435: 
duke@435: 
duke@435: // Implementation of NewArray
duke@435: 
duke@435: void NewArray::other_values_do(void f(Value*)) {
duke@435:   if (state_before() != NULL) state_before()->values_do(f);
duke@435: }
duke@435: 
duke@435: 
duke@435: // Implementation of TypeCheck
duke@435: 
duke@435: void TypeCheck::other_values_do(void f(Value*)) {
duke@435:   if (state_before() != NULL) state_before()->values_do(f);
duke@435: }
duke@435: 
duke@435: 
duke@435: // Implementation of BlockBegin
duke@435: 
duke@435: int BlockBegin::_next_block_id = 0;
duke@435: 
duke@435: 
duke@435: void BlockBegin::set_end(BlockEnd* end) {
duke@435:   assert(end != NULL, "should not reset block end to NULL");
duke@435:   BlockEnd* old_end = _end;
duke@435:   if (end == old_end) {
duke@435:     return;
duke@435:   }
duke@435:   // Must make the predecessors/successors match up with the
duke@435:   // BlockEnd's notion.
duke@435:   int i, n;
duke@435:   if (old_end != NULL) {
duke@435:     // disconnect from the old end
duke@435:     old_end->set_begin(NULL);
duke@435: 
duke@435:     // disconnect this block from it's current successors
duke@435:     for (i = 0; i < _successors.length(); i++) {
duke@435:       _successors.at(i)->remove_predecessor(this);
duke@435:     }
duke@435:   }
duke@435:   _end = end;
duke@435: 
duke@435:   _successors.clear();
duke@435:   // Now reset successors list based on BlockEnd
duke@435:   n = end->number_of_sux();
duke@435:   for (i = 0; i < n; i++) {
duke@435:     BlockBegin* sux = end->sux_at(i);
duke@435:     _successors.append(sux);
duke@435:     sux->_predecessors.append(this);
duke@435:   }
duke@435:   _end->set_begin(this);
duke@435: }
duke@435: 
duke@435: 
duke@435: void BlockBegin::disconnect_edge(BlockBegin* from, BlockBegin* to) {
duke@435:   // disconnect any edges between from and to
duke@435: #ifndef PRODUCT
duke@435:   if (PrintIR && Verbose) {
duke@435:     tty->print_cr("Disconnected edge B%d -> B%d", from->block_id(), to->block_id());
duke@435:   }
duke@435: #endif
duke@435:   for (int s = 0; s < from->number_of_sux();) {
duke@435:     BlockBegin* sux = from->sux_at(s);
duke@435:     if (sux == to) {
duke@435:       int index = sux->_predecessors.index_of(from);
duke@435:       if (index >= 0) {
duke@435:         sux->_predecessors.remove_at(index);
duke@435:       }
duke@435:       from->_successors.remove_at(s);
duke@435:     } else {
duke@435:       s++;
duke@435:     }
duke@435:   }
duke@435: }
duke@435: 
duke@435: 
duke@435: void BlockBegin::disconnect_from_graph() {
duke@435:   // disconnect this block from all other blocks
duke@435:   for (int p = 0; p < number_of_preds(); p++) {
duke@435:     pred_at(p)->remove_successor(this);
duke@435:   }
duke@435:   for (int s = 0; s < number_of_sux(); s++) {
duke@435:     sux_at(s)->remove_predecessor(this);
duke@435:   }
duke@435: }
duke@435: 
duke@435: void BlockBegin::substitute_sux(BlockBegin* old_sux, BlockBegin* new_sux) {
duke@435:   // modify predecessors before substituting successors
duke@435:   for (int i = 0; i < number_of_sux(); i++) {
duke@435:     if (sux_at(i) == old_sux) {
duke@435:       // remove old predecessor before adding new predecessor
duke@435:       // otherwise there is a dead predecessor in the list
duke@435:       new_sux->remove_predecessor(old_sux);
duke@435:       new_sux->add_predecessor(this);
duke@435:     }
duke@435:   }
duke@435:   old_sux->remove_predecessor(this);
duke@435:   end()->substitute_sux(old_sux, new_sux);
duke@435: }
duke@435: 
duke@435: 
duke@435: 
duke@435: // In general it is not possible to calculate a value for the field "depth_first_number"
duke@435: // of the inserted block, without recomputing the values of the other blocks
duke@435: // in the CFG. Therefore the value of "depth_first_number" in BlockBegin becomes meaningless.
duke@435: BlockBegin* BlockBegin::insert_block_between(BlockBegin* sux) {
duke@435:   // Try to make the bci close to a block with a single pred or sux,
duke@435:   // since this make the block layout algorithm work better.
duke@435:   int bci = -1;
duke@435:   if (sux->number_of_preds() == 1) {
duke@435:     bci = sux->bci();
duke@435:   } else {
duke@435:     bci = end()->bci();
duke@435:   }
duke@435: 
duke@435:   BlockBegin* new_sux = new BlockBegin(bci);
duke@435: 
duke@435:   // mark this block (special treatment when block order is computed)
duke@435:   new_sux->set(critical_edge_split_flag);
duke@435: 
duke@435:   // This goto is not a safepoint.
duke@435:   Goto* e = new Goto(sux, false);
duke@435:   new_sux->set_next(e, bci);
duke@435:   new_sux->set_end(e);
duke@435:   // setup states
duke@435:   ValueStack* s = end()->state();
duke@435:   new_sux->set_state(s->copy());
duke@435:   e->set_state(s->copy());
duke@435:   assert(new_sux->state()->locals_size() == s->locals_size(), "local size mismatch!");
duke@435:   assert(new_sux->state()->stack_size() == s->stack_size(), "stack size mismatch!");
duke@435:   assert(new_sux->state()->locks_size() == s->locks_size(), "locks size mismatch!");
duke@435: 
duke@435:   // link predecessor to new block
duke@435:   end()->substitute_sux(sux, new_sux);
duke@435: 
duke@435:   // The ordering needs to be the same, so remove the link that the
duke@435:   // set_end call above added and substitute the new_sux for this
duke@435:   // block.
duke@435:   sux->remove_predecessor(new_sux);
duke@435: 
duke@435:   // the successor could be the target of a switch so it might have
duke@435:   // multiple copies of this predecessor, so substitute the new_sux
duke@435:   // for the first and delete the rest.
duke@435:   bool assigned = false;
duke@435:   BlockList& list = sux->_predecessors;
duke@435:   for (int i = 0; i < list.length(); i++) {
duke@435:     BlockBegin** b = list.adr_at(i);
duke@435:     if (*b == this) {
duke@435:       if (assigned) {
duke@435:         list.remove_at(i);
duke@435:         // reprocess this index
duke@435:         i--;
duke@435:       } else {
duke@435:         assigned = true;
duke@435:         *b = new_sux;
duke@435:       }
duke@435:       // link the new block back to it's predecessors.
duke@435:       new_sux->add_predecessor(this);
duke@435:     }
duke@435:   }
duke@435:   assert(assigned == true, "should have assigned at least once");
duke@435:   return new_sux;
duke@435: }
duke@435: 
duke@435: 
duke@435: void BlockBegin::remove_successor(BlockBegin* pred) {
duke@435:   int idx;
duke@435:   while ((idx = _successors.index_of(pred)) >= 0) {
duke@435:     _successors.remove_at(idx);
duke@435:   }
duke@435: }
duke@435: 
duke@435: 
duke@435: void BlockBegin::add_predecessor(BlockBegin* pred) {
duke@435:   _predecessors.append(pred);
duke@435: }
duke@435: 
duke@435: 
duke@435: void BlockBegin::remove_predecessor(BlockBegin* pred) {
duke@435:   int idx;
duke@435:   while ((idx = _predecessors.index_of(pred)) >= 0) {
duke@435:     _predecessors.remove_at(idx);
duke@435:   }
duke@435: }
duke@435: 
duke@435: 
duke@435: void BlockBegin::add_exception_handler(BlockBegin* b) {
duke@435:   assert(b != NULL && (b->is_set(exception_entry_flag)), "exception handler must exist");
duke@435:   // add only if not in the list already
duke@435:   if (!_exception_handlers.contains(b)) _exception_handlers.append(b);
duke@435: }
duke@435: 
duke@435: int BlockBegin::add_exception_state(ValueStack* state) {
duke@435:   assert(is_set(exception_entry_flag), "only for xhandlers");
duke@435:   if (_exception_states == NULL) {
duke@435:     _exception_states = new ValueStackStack(4);
duke@435:   }
duke@435:   _exception_states->append(state);
duke@435:   return _exception_states->length() - 1;
duke@435: }
duke@435: 
duke@435: 
duke@435: void BlockBegin::iterate_preorder(boolArray& mark, BlockClosure* closure) {
duke@435:   if (!mark.at(block_id())) {
duke@435:     mark.at_put(block_id(), true);
duke@435:     closure->block_do(this);
duke@435:     BlockEnd* e = end(); // must do this after block_do because block_do may change it!
duke@435:     { for (int i = number_of_exception_handlers() - 1; i >= 0; i--) exception_handler_at(i)->iterate_preorder(mark, closure); }
duke@435:     { for (int i = e->number_of_sux            () - 1; i >= 0; i--) e->sux_at           (i)->iterate_preorder(mark, closure); }
duke@435:   }
duke@435: }
duke@435: 
duke@435: 
duke@435: void BlockBegin::iterate_postorder(boolArray& mark, BlockClosure* closure) {
duke@435:   if (!mark.at(block_id())) {
duke@435:     mark.at_put(block_id(), true);
duke@435:     BlockEnd* e = end();
duke@435:     { for (int i = number_of_exception_handlers() - 1; i >= 0; i--) exception_handler_at(i)->iterate_postorder(mark, closure); }
duke@435:     { for (int i = e->number_of_sux            () - 1; i >= 0; i--) e->sux_at           (i)->iterate_postorder(mark, closure); }
duke@435:     closure->block_do(this);
duke@435:   }
duke@435: }
duke@435: 
duke@435: 
duke@435: void BlockBegin::iterate_preorder(BlockClosure* closure) {
duke@435:   boolArray mark(number_of_blocks(), false);
duke@435:   iterate_preorder(mark, closure);
duke@435: }
duke@435: 
duke@435: 
duke@435: void BlockBegin::iterate_postorder(BlockClosure* closure) {
duke@435:   boolArray mark(number_of_blocks(), false);
duke@435:   iterate_postorder(mark, closure);
duke@435: }
duke@435: 
duke@435: 
duke@435: void BlockBegin::block_values_do(void f(Value*)) {
duke@435:   for (Instruction* n = this; n != NULL; n = n->next()) n->values_do(f);
duke@435: }
duke@435: 
duke@435: 
duke@435: #ifndef PRODUCT
duke@435:   #define TRACE_PHI(code) if (PrintPhiFunctions) { code; }
duke@435: #else
duke@435:   #define TRACE_PHI(coce)
duke@435: #endif
duke@435: 
duke@435: 
duke@435: bool BlockBegin::try_merge(ValueStack* new_state) {
duke@435:   TRACE_PHI(tty->print_cr("********** try_merge for block B%d", block_id()));
duke@435: 
duke@435:   // local variables used for state iteration
duke@435:   int index;
duke@435:   Value new_value, existing_value;
duke@435: 
duke@435:   ValueStack* existing_state = state();
duke@435:   if (existing_state == NULL) {
duke@435:     TRACE_PHI(tty->print_cr("first call of try_merge for this block"));
duke@435: 
duke@435:     if (is_set(BlockBegin::was_visited_flag)) {
duke@435:       // this actually happens for complicated jsr/ret structures
duke@435:       return false; // BAILOUT in caller
duke@435:     }
duke@435: 
duke@435:     // copy state because it is altered
duke@435:     new_state = new_state->copy();
duke@435: 
duke@435:     // Use method liveness to invalidate dead locals
duke@435:     MethodLivenessResult liveness = new_state->scope()->method()->liveness_at_bci(bci());
duke@435:     if (liveness.is_valid()) {
duke@435:       assert((int)liveness.size() == new_state->locals_size(), "error in use of liveness");
duke@435: 
duke@435:       for_each_local_value(new_state, index, new_value) {
duke@435:         if (!liveness.at(index) || new_value->type()->is_illegal()) {
duke@435:           new_state->invalidate_local(index);
duke@435:           TRACE_PHI(tty->print_cr("invalidating dead local %d", index));
duke@435:         }
duke@435:       }
duke@435:     }
duke@435: 
duke@435:     if (is_set(BlockBegin::parser_loop_header_flag)) {
duke@435:       TRACE_PHI(tty->print_cr("loop header block, initializing phi functions"));
duke@435: 
duke@435:       for_each_stack_value(new_state, index, new_value) {
duke@435:         new_state->setup_phi_for_stack(this, index);
duke@435:         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));
duke@435:       }
duke@435: 
duke@435:       BitMap requires_phi_function = new_state->scope()->requires_phi_function();
duke@435: 
duke@435:       for_each_local_value(new_state, index, new_value) {
duke@435:         bool requires_phi = requires_phi_function.at(index) || (new_value->type()->is_double_word() && requires_phi_function.at(index + 1));
duke@435:         if (requires_phi || !SelectivePhiFunctions) {
duke@435:           new_state->setup_phi_for_local(this, index);
duke@435:           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));
duke@435:         }
duke@435:       }
duke@435:     }
duke@435: 
duke@435:     // initialize state of block
duke@435:     set_state(new_state);
duke@435: 
duke@435:   } else if (existing_state->is_same_across_scopes(new_state)) {
duke@435:     TRACE_PHI(tty->print_cr("exisiting state found"));
duke@435: 
duke@435:     // Inlining may cause the local state not to match up, so walk up
duke@435:     // the new state until we get to the same scope as the
duke@435:     // existing and then start processing from there.
duke@435:     while (existing_state->scope() != new_state->scope()) {
duke@435:       new_state = new_state->caller_state();
duke@435:       assert(new_state != NULL, "could not match up scopes");
duke@435: 
duke@435:       assert(false, "check if this is necessary");
duke@435:     }
duke@435: 
duke@435:     assert(existing_state->scope() == new_state->scope(), "not matching");
duke@435:     assert(existing_state->locals_size() == new_state->locals_size(), "not matching");
duke@435:     assert(existing_state->stack_size() == new_state->stack_size(), "not matching");
duke@435: 
duke@435:     if (is_set(BlockBegin::was_visited_flag)) {
duke@435:       TRACE_PHI(tty->print_cr("loop header block, phis must be present"));
duke@435: 
duke@435:       if (!is_set(BlockBegin::parser_loop_header_flag)) {
duke@435:         // this actually happens for complicated jsr/ret structures
duke@435:         return false; // BAILOUT in caller
duke@435:       }
duke@435: 
duke@435:       for_each_local_value(existing_state, index, existing_value) {
duke@435:         Value new_value = new_state->local_at(index);
duke@435:         if (new_value == NULL || new_value->type()->tag() != existing_value->type()->tag()) {
duke@435:           // The old code invalidated the phi function here
duke@435:           // Because dead locals are replaced with NULL, this is a very rare case now, so simply bail out
duke@435:           return false; // BAILOUT in caller
duke@435:         }
duke@435:       }
duke@435: 
duke@435: #ifdef ASSERT
duke@435:       // check that all necessary phi functions are present
duke@435:       for_each_stack_value(existing_state, index, existing_value) {
duke@435:         assert(existing_value->as_Phi() != NULL && existing_value->as_Phi()->block() == this, "phi function required");
duke@435:       }
duke@435:       for_each_local_value(existing_state, index, existing_value) {
duke@435:         assert(existing_value == new_state->local_at(index) || (existing_value->as_Phi() != NULL && existing_value->as_Phi()->as_Phi()->block() == this), "phi function required");
duke@435:       }
duke@435: #endif
duke@435: 
duke@435:     } else {
duke@435:       TRACE_PHI(tty->print_cr("creating phi functions on demand"));
duke@435: 
duke@435:       // create necessary phi functions for stack
duke@435:       for_each_stack_value(existing_state, index, existing_value) {
duke@435:         Value new_value = new_state->stack_at(index);
duke@435:         Phi* existing_phi = existing_value->as_Phi();
duke@435: 
duke@435:         if (new_value != existing_value && (existing_phi == NULL || existing_phi->block() != this)) {
duke@435:           existing_state->setup_phi_for_stack(this, index);
duke@435:           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));
duke@435:         }
duke@435:       }
duke@435: 
duke@435:       // create necessary phi functions for locals
duke@435:       for_each_local_value(existing_state, index, existing_value) {
duke@435:         Value new_value = new_state->local_at(index);
duke@435:         Phi* existing_phi = existing_value->as_Phi();
duke@435: 
duke@435:         if (new_value == NULL || new_value->type()->tag() != existing_value->type()->tag()) {
duke@435:           existing_state->invalidate_local(index);
duke@435:           TRACE_PHI(tty->print_cr("invalidating local %d because of type mismatch", index));
duke@435:         } else if (new_value != existing_value && (existing_phi == NULL || existing_phi->block() != this)) {
duke@435:           existing_state->setup_phi_for_local(this, index);
duke@435:           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));
duke@435:         }
duke@435:       }
duke@435:     }
duke@435: 
duke@435:     assert(existing_state->caller_state() == new_state->caller_state(), "caller states must be equal");
duke@435: 
duke@435:   } else {
duke@435:     assert(false, "stack or locks not matching (invalid bytecodes)");
duke@435:     return false;
duke@435:   }
duke@435: 
duke@435:   TRACE_PHI(tty->print_cr("********** try_merge for block B%d successful", block_id()));
duke@435: 
duke@435:   return true;
duke@435: }
duke@435: 
duke@435: 
duke@435: #ifndef PRODUCT
duke@435: void BlockBegin::print_block() {
duke@435:   InstructionPrinter ip;
duke@435:   print_block(ip, false);
duke@435: }
duke@435: 
duke@435: 
duke@435: void BlockBegin::print_block(InstructionPrinter& ip, bool live_only) {
duke@435:   ip.print_instr(this); tty->cr();
duke@435:   ip.print_stack(this->state()); tty->cr();
duke@435:   ip.print_inline_level(this);
duke@435:   ip.print_head();
duke@435:   for (Instruction* n = next(); n != NULL; n = n->next()) {
duke@435:     if (!live_only || n->is_pinned() || n->use_count() > 0) {
duke@435:       ip.print_line(n);
duke@435:     }
duke@435:   }
duke@435:   tty->cr();
duke@435: }
duke@435: #endif // PRODUCT
duke@435: 
duke@435: 
duke@435: // Implementation of BlockList
duke@435: 
duke@435: void BlockList::iterate_forward (BlockClosure* closure) {
duke@435:   const int l = length();
duke@435:   for (int i = 0; i < l; i++) closure->block_do(at(i));
duke@435: }
duke@435: 
duke@435: 
duke@435: void BlockList::iterate_backward(BlockClosure* closure) {
duke@435:   for (int i = length() - 1; i >= 0; i--) closure->block_do(at(i));
duke@435: }
duke@435: 
duke@435: 
duke@435: void BlockList::blocks_do(void f(BlockBegin*)) {
duke@435:   for (int i = length() - 1; i >= 0; i--) f(at(i));
duke@435: }
duke@435: 
duke@435: 
duke@435: void BlockList::values_do(void f(Value*)) {
duke@435:   for (int i = length() - 1; i >= 0; i--) at(i)->block_values_do(f);
duke@435: }
duke@435: 
duke@435: 
duke@435: #ifndef PRODUCT
duke@435: void BlockList::print(bool cfg_only, bool live_only) {
duke@435:   InstructionPrinter ip;
duke@435:   for (int i = 0; i < length(); i++) {
duke@435:     BlockBegin* block = at(i);
duke@435:     if (cfg_only) {
duke@435:       ip.print_instr(block); tty->cr();
duke@435:     } else {
duke@435:       block->print_block(ip, live_only);
duke@435:     }
duke@435:   }
duke@435: }
duke@435: #endif // PRODUCT
duke@435: 
duke@435: 
duke@435: // Implementation of BlockEnd
duke@435: 
duke@435: void BlockEnd::set_begin(BlockBegin* begin) {
duke@435:   BlockList* sux = NULL;
duke@435:   if (begin != NULL) {
duke@435:     sux = begin->successors();
duke@435:   } else if (_begin != NULL) {
duke@435:     // copy our sux list
duke@435:     BlockList* sux = new BlockList(_begin->number_of_sux());
duke@435:     for (int i = 0; i < _begin->number_of_sux(); i++) {
duke@435:       sux->append(_begin->sux_at(i));
duke@435:     }
duke@435:   }
duke@435:   _sux = sux;
duke@435:   _begin = begin;
duke@435: }
duke@435: 
duke@435: 
duke@435: void BlockEnd::substitute_sux(BlockBegin* old_sux, BlockBegin* new_sux) {
duke@435:   substitute(*_sux, old_sux, new_sux);
duke@435: }
duke@435: 
duke@435: 
duke@435: void BlockEnd::other_values_do(void f(Value*)) {
duke@435:   if (state_before() != NULL) state_before()->values_do(f);
duke@435: }
duke@435: 
duke@435: 
duke@435: // Implementation of Phi
duke@435: 
duke@435: // Normal phi functions take their operands from the last instruction of the
duke@435: // predecessor. Special handling is needed for xhanlder entries because there
duke@435: // the state of arbitrary instructions are needed.
duke@435: 
duke@435: Value Phi::operand_at(int i) const {
duke@435:   ValueStack* state;
duke@435:   if (_block->is_set(BlockBegin::exception_entry_flag)) {
duke@435:     state = _block->exception_state_at(i);
duke@435:   } else {
duke@435:     state = _block->pred_at(i)->end()->state();
duke@435:   }
duke@435:   assert(state != NULL, "");
duke@435: 
duke@435:   if (is_local()) {
duke@435:     return state->local_at(local_index());
duke@435:   } else {
duke@435:     return state->stack_at(stack_index());
duke@435:   }
duke@435: }
duke@435: 
duke@435: 
duke@435: int Phi::operand_count() const {
duke@435:   if (_block->is_set(BlockBegin::exception_entry_flag)) {
duke@435:     return _block->number_of_exception_states();
duke@435:   } else {
duke@435:     return _block->number_of_preds();
duke@435:   }
duke@435: }
duke@435: 
duke@435: 
duke@435: // Implementation of Throw
duke@435: 
duke@435: void Throw::state_values_do(void f(Value*)) {
duke@435:   BlockEnd::state_values_do(f);
duke@435: }