Mercurial > hg > graal-compiler
diff src/share/vm/c1/c1_Instruction.cpp @ 0:a61af66fc99e jdk7-b24
Initial load
author | duke |
---|---|
date | Sat, 01 Dec 2007 00:00:00 +0000 |
parents | |
children | 3cf667df43ef |
line wrap: on
line diff
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/share/vm/c1/c1_Instruction.cpp Sat Dec 01 00:00:00 2007 +0000 @@ -0,0 +1,1006 @@ +/* + * 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); +}