view src/share/vm/shark/sharkConstant.cpp @ 1941:79d04223b8a5

Added caching for resolved types and resolved fields. This is crucial, because the local load elimination will lead to wrong results, if field equality (of two RiField objects with the same object and the same RiType) is not given. The caching makes sure that the default equals implementation is sufficient.
author Thomas Wuerthinger <wuerthinger@ssw.jku.at>
date Tue, 28 Dec 2010 18:33:26 +0100
parents d2ede61b7a12
children f95d63e2154a
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/*
 * Copyright (c) 1999, 2007, Oracle and/or its affiliates. All rights reserved.
 * Copyright 2009 Red Hat, Inc.
 * 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 "incls/_precompiled.incl"
#include "incls/_sharkConstant.cpp.incl"

using namespace llvm;

SharkConstant* SharkConstant::for_ldc(ciBytecodeStream *iter) {
  ciConstant constant = iter->get_constant();
  ciType *type = NULL;
  if (constant.basic_type() == T_OBJECT) {
    ciEnv *env = ciEnv::current();
    if (constant.as_object()->is_klass())
      type = env->Class_klass();
    else
      type = env->String_klass();
  }
  return new SharkConstant(constant, type);
}

SharkConstant* SharkConstant::for_field(ciBytecodeStream *iter) {
  bool will_link;
  ciField *field = iter->get_field(will_link);
  assert(will_link, "typeflow responsibility");

  return new SharkConstant(field->constant_value(), field->type());
}

SharkConstant::SharkConstant(ciConstant constant, ciType *type) {
  SharkValue *value = NULL;

  switch (constant.basic_type()) {
  case T_BOOLEAN:
  case T_BYTE:
  case T_CHAR:
  case T_SHORT:
  case T_INT:
    value = SharkValue::jint_constant(constant.as_int());
    break;

  case T_LONG:
    value = SharkValue::jlong_constant(constant.as_long());
    break;

  case T_FLOAT:
    value = SharkValue::jfloat_constant(constant.as_float());
    break;

  case T_DOUBLE:
    value = SharkValue::jdouble_constant(constant.as_double());
    break;

  case T_OBJECT:
  case T_ARRAY:
    break;

  case T_ILLEGAL:
    // out of memory
    _is_loaded = false;
    return;

  default:
    tty->print_cr("Unhandled type %s", type2name(constant.basic_type()));
    ShouldNotReachHere();
  }

  // Handle primitive types.  We create SharkValues for these
  // now; doing so doesn't emit any code, and it allows us to
  // delegate a bunch of stuff to the SharkValue code.
  if (value) {
    _value       = value;
    _is_loaded   = true;
    _is_nonzero  = value->zero_checked();
    _is_two_word = value->is_two_word();
    return;
  }

  // Handle reference types.  This is tricky because some
  // ciObjects are psuedo-objects that refer to oops which
  // have yet to be created.  We need to spot the unloaded
  // objects (which differ between ldc* and get*, thanks!)
  ciObject *object = constant.as_object();
  assert(type != NULL, "shouldn't be");
  if (object->is_klass()) {
    // The constant returned for a klass is the ciKlass
    // for the entry, but we want the java_mirror.
    ciKlass *klass = object->as_klass();
    if (!klass->is_loaded()) {
      _is_loaded = false;
      return;
    }
    object = klass->java_mirror();
  }
  if (object->is_null_object() || !object->can_be_constant()) {
    _is_loaded = false;
    return;
  }

  _value       = NULL;
  _object      = object;
  _type        = type;
  _is_loaded   = true;
  _is_nonzero  = true;
  _is_two_word = false;
}