--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/c1/c1_ValueStack.cpp	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,285 @@
+/*
+ * Copyright (c) 1999, 2016, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "c1/c1_IR.hpp"
+#include "c1/c1_InstructionPrinter.hpp"
+#include "c1/c1_ValueStack.hpp"
+
+
+// Implementation of ValueStack
+
+ValueStack::ValueStack(IRScope* scope, ValueStack* caller_state)
+: _scope(scope)
+, _caller_state(caller_state)
+, _bci(-99)
+, _kind(Parsing)
+, _locals(scope->method()->max_locals(), scope->method()->max_locals(), NULL)
+, _stack(scope->method()->max_stack())
+, _locks()
+{
+  verify();
+}
+
+
+ValueStack::ValueStack(ValueStack* copy_from, Kind kind, int bci)
+  : _scope(copy_from->scope())
+  , _caller_state(copy_from->caller_state())
+  , _bci(bci)
+  , _kind(kind)
+  , _locals()
+  , _stack()
+  , _locks(copy_from->locks_size())
+{
+  assert(kind != EmptyExceptionState || !Compilation::current()->env()->should_retain_local_variables(), "need locals");
+  if (kind != EmptyExceptionState) {
+    // only allocate space if we need to copy the locals-array
+    _locals = Values(copy_from->locals_size());
+    _locals.appendAll(&copy_from->_locals);
+  }
+
+  if (kind != ExceptionState && kind != EmptyExceptionState) {
+    if (kind == Parsing) {
+      // stack will be modified, so reserve enough space to avoid resizing
+      _stack = Values(scope()->method()->max_stack());
+    } else {
+      // stack will not be modified, so do not waste space
+      _stack = Values(copy_from->stack_size());
+    }
+    _stack.appendAll(&copy_from->_stack);
+  }
+
+  _locks.appendAll(&copy_from->_locks);
+
+  verify();
+}
+
+
+bool ValueStack::is_same(ValueStack* s) {
+  if (scope() != s->scope()) return false;
+  if (caller_state() != s->caller_state()) return false;
+
+  if (locals_size() != s->locals_size()) return false;
+  if (stack_size() != s->stack_size()) return false;
+  if (locks_size() != s->locks_size()) return false;
+
+  // compare each stack element with the corresponding stack element of s
+  int index;
+  Value value;
+  for_each_stack_value(this, index, value) {
+    if (value->type()->tag() != s->stack_at(index)->type()->tag()) return false;
+  }
+  for_each_lock_value(this, index, value) {
+    if (value != s->lock_at(index)) return false;
+  }
+  return true;
+}
+
+void ValueStack::clear_locals() {
+  for (int i = _locals.length() - 1; i >= 0; i--) {
+    _locals.at_put(i, NULL);
+  }
+}
+
+
+void ValueStack::pin_stack_for_linear_scan() {
+  for_each_state_value(this, v,
+    if (v->as_Constant() == NULL && v->as_Local() == NULL) {
+      v->pin(Instruction::PinStackForStateSplit);
+    }
+  );
+}
+
+
+// apply function to all values of a list; factored out from values_do(f)
+void ValueStack::apply(Values list, ValueVisitor* f) {
+  for (int i = 0; i < list.length(); i++) {
+    Value* va = list.adr_at(i);
+    Value v0 = *va;
+    if (v0 != NULL && !v0->type()->is_illegal()) {
+      f->visit(va);
+#ifdef ASSERT
+      Value v1 = *va;
+      assert(v1->type()->is_illegal() || v0->type()->tag() == v1->type()->tag(), "types must match");
+      assert(!v1->type()->is_double_word() || list.at(i + 1) == NULL, "hi-word of doubleword value must be NULL");
+#endif
+      if (v0->type()->is_double_word()) i++;
+    }
+  }
+}
+
+
+void ValueStack::values_do(ValueVisitor* f) {
+  ValueStack* state = this;
+  for_each_state(state) {
+    apply(state->_locals, f);
+    apply(state->_stack, f);
+    apply(state->_locks, f);
+  }
+}
+
+
+Values* ValueStack::pop_arguments(int argument_size) {
+  assert(stack_size() >= argument_size, "stack too small or too many arguments");
+  int base = stack_size() - argument_size;
+  Values* args = new Values(argument_size);
+  for (int i = base; i < stack_size();) args->push(stack_at_inc(i));
+  truncate_stack(base);
+  return args;
+}
+
+
+int ValueStack::total_locks_size() const {
+  int num_locks = 0;
+  const ValueStack* state = this;
+  for_each_state(state) {
+    num_locks += state->locks_size();
+  }
+  return num_locks;
+}
+
+int ValueStack::lock(Value obj) {
+  _locks.push(obj);
+  int num_locks = total_locks_size();
+  scope()->set_min_number_of_locks(num_locks);
+  return num_locks - 1;
+}
+
+
+int ValueStack::unlock() {
+  _locks.pop();
+  return total_locks_size();
+}
+
+
+void ValueStack::setup_phi_for_stack(BlockBegin* b, int index) {
+  assert(stack_at(index)->as_Phi() == NULL || stack_at(index)->as_Phi()->block() != b, "phi function already created");
+
+  ValueType* t = stack_at(index)->type();
+  Value phi = new Phi(t, b, -index - 1);
+  _stack.at_put(index, phi);
+
+  assert(!t->is_double_word() || _stack.at(index + 1) == NULL, "hi-word of doubleword value must be NULL");
+}
+
+void ValueStack::setup_phi_for_local(BlockBegin* b, int index) {
+  assert(local_at(index)->as_Phi() == NULL || local_at(index)->as_Phi()->block() != b, "phi function already created");
+
+  ValueType* t = local_at(index)->type();
+  Value phi = new Phi(t, b, index);
+  store_local(index, phi);
+}
+
+#ifndef PRODUCT
+
+void ValueStack::print() {
+  scope()->method()->print_name();
+  tty->cr();
+  if (stack_is_empty()) {
+    tty->print_cr("empty stack");
+  } else {
+    InstructionPrinter ip;
+    for (int i = 0; i < stack_size();) {
+      Value t = stack_at_inc(i);
+      tty->print("%2d  ", i);
+      tty->print("%c%d ", t->type()->tchar(), t->id());
+      ip.print_instr(t);
+      tty->cr();
+    }
+  }
+  if (!no_active_locks()) {
+    InstructionPrinter ip;
+    for (int i = 0; i < locks_size(); i++) {
+      Value t = lock_at(i);
+      tty->print("lock %2d  ", i);
+      if (t == NULL) {
+        tty->print("this");
+      } else {
+        tty->print("%c%d ", t->type()->tchar(), t->id());
+        ip.print_instr(t);
+      }
+      tty->cr();
+    }
+  }
+  if (locals_size() > 0) {
+    InstructionPrinter ip;
+    for (int i = 0; i < locals_size();) {
+      Value l = _locals.at(i);
+      tty->print("local %d ", i);
+      if (l == NULL) {
+        tty->print("null");
+        i ++;
+      } else {
+        tty->print("%c%d ", l->type()->tchar(), l->id());
+        ip.print_instr(l);
+        if (l->type()->is_illegal() || l->type()->is_single_word()) i ++; else i += 2;
+      }
+      tty->cr();
+    }
+  }
+
+  if (caller_state() != NULL) {
+    caller_state()->print();
+  }
+}
+
+
+void ValueStack::verify() {
+  assert(scope() != NULL, "scope must exist");
+  if (caller_state() != NULL) {
+    assert(caller_state()->scope() == scope()->caller(), "invalid caller scope");
+    caller_state()->verify();
+  }
+
+  if (kind() == Parsing) {
+    assert(bci() == -99, "bci not defined during parsing");
+  } else {
+    assert(bci() >= -1, "bci out of range");
+    assert(bci() < scope()->method()->code_size(), "bci out of range");
+    assert(bci() == SynchronizationEntryBCI || Bytecodes::is_defined(scope()->method()->java_code_at_bci(bci())), "make sure bci points at a real bytecode");
+    assert(scope()->method()->liveness_at_bci(bci()).is_valid(), "liveness at bci must be valid");
+  }
+
+  int i;
+  for (i = 0; i < stack_size(); i++) {
+    Value v = _stack.at(i);
+    if (v == NULL) {
+      assert(_stack.at(i - 1)->type()->is_double_word(), "only hi-words are NULL on stack");
+    } else if (v->type()->is_double_word()) {
+      assert(_stack.at(i + 1) == NULL, "hi-word must be NULL");
+    }
+  }
+
+  for (i = 0; i < locals_size(); i++) {
+    Value v = _locals.at(i);
+    if (v != NULL && v->type()->is_double_word()) {
+      assert(_locals.at(i + 1) == NULL, "hi-word must be NULL");
+    }
+  }
+
+  for_each_state_value(this, v,
+    assert(v != NULL, "just test if state-iteration succeeds");
+  );
+}
+#endif // PRODUCT