jdk8-mips64-public/hotspot: src/share/vm/ci/ciField.hpp@b2ee5dc63353 (annotated)

src/share/vm/ci/ciField.hpp@b2ee5dc63353 (annotated)

src/share/vm/ci/ciField.hpp

Wed, 23 Oct 2013 12:40:23 +0200

author: roland
date: Wed, 23 Oct 2013 12:40:23 +0200
changeset 5991: b2ee5dc63353
parent 5732: b2e698d2276c
child 6876: 710a3c8b516e
child 8664: 00cbb581da94
permissions: -rw-r--r--

8024070: C2 needs some form of type speculation
Summary: record unused type profile information with type system, propagate and use it.
Reviewed-by: kvn, twisti

 /*
  * Copyright (c) 1999, 2013, 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.
  *
  */
 #ifndef SHARE_VM_CI_CIFIELD_HPP
 #define SHARE_VM_CI_CIFIELD_HPP
 #include "ci/ciClassList.hpp"
 #include "ci/ciConstant.hpp"
 #include "ci/ciFlags.hpp"
 #include "ci/ciInstance.hpp"
 // ciField
 //
 // This class represents the result of a field lookup in the VM.
 // The lookup may not succeed, in which case the information in
 // the ciField will be incomplete.
 class ciField : public ResourceObj {
   CI_PACKAGE_ACCESS
   friend class ciEnv;
   friend class ciInstanceKlass;
   friend class NonStaticFieldFiller;
 private:
   ciFlags          _flags;
   ciInstanceKlass* _holder;
   ciSymbol*        _name;
   ciSymbol*        _signature;
   ciType*          _type;
   int              _offset;
   bool             _is_constant;
   ciInstanceKlass* _known_to_link_with_put;
   ciInstanceKlass* _known_to_link_with_get;
   ciConstant       _constant_value;
   ciType* compute_type();
   ciType* compute_type_impl();
   ciField(ciInstanceKlass* klass, int index);
   ciField(fieldDescriptor* fd);
   // shared constructor code
   void initialize_from(fieldDescriptor* fd);
 public:
   ciFlags flags() { return _flags; }
   // Of which klass is this field a member?
   //
   // Usage note: the declared holder of a field is the class
   // referenced by name in the bytecodes.  The canonical holder
   // is the most general class which holds the field.  This
   // method returns the canonical holder.  The declared holder
   // can be accessed via a method in ciBytecodeStream.
   //
   // Ex.
   //     class A {
   //       public int f = 7;
   //     }
   //     class B extends A {
   //       public void test() {
   //         System.out.println(f);
   //       }
   //     }
   //
   //   A java compiler is permitted to compile the access to
   //   field f as:
   //
   //     getfield B.f
   //
   //   In that case the declared holder of f would be B and
   //   the canonical holder of f would be A.
   ciInstanceKlass* holder() { return _holder; }
   // Name of this field?
   ciSymbol* name() { return _name; }
   // Signature of this field?
   ciSymbol* signature() { return _signature; }
   // Of what type is this field?
   ciType* type() { return (_type == NULL) ? compute_type() : _type; }
   // How is this field actually stored in memory?
   BasicType layout_type() { return type2field[(_type == NULL) ? T_OBJECT : _type->basic_type()]; }
   // How big is this field in memory?
   int size_in_bytes() { return type2aelembytes(layout_type()); }
   // What is the offset of this field?
   int offset() {
     assert(_offset >= 1, "illegal call to offset()");
     return _offset;
   }
   // Same question, explicit units.  (Fields are aligned to the byte level.)
   int offset_in_bytes() {
     return offset();
   }
   // Is this field shared?
   bool is_shared() {
     // non-static fields of shared holders are cached
     return _holder->is_shared() && !is_static();
   }
   // Is this field a constant?
   //
   // Clarification: A field is considered constant if:
   //   1. The field is both static and final
   //   2. The canonical holder of the field has undergone
   //      static initialization.
   //   3. If the field is an object or array, then the oop
   //      in question is allocated in perm space.
   //   4. The field is not one of the special static/final
   //      non-constant fields.  These are java.lang.System.in
   //      and java.lang.System.out.  Abomination.
   //
   // A field is also considered constant if it is marked @Stable
   // and is non-null (or non-zero, if a primitive).
   // For non-static fields, the null/zero check must be
   // arranged by the user, as constant_value().is_null_or_zero().
   bool is_constant() { return _is_constant; }
   // Get the constant value of this field.
   ciConstant constant_value() {
     assert(is_static() && is_constant(), "illegal call to constant_value()");
     return _constant_value;
   }
   // Get the constant value of non-static final field in the given
   // object.
   ciConstant constant_value_of(ciObject* object) {
     assert(!is_static() && is_constant(), "only if field is non-static constant");
     assert(object->is_instance(), "must be instance");
     return object->as_instance()->field_value(this);
   }
   // Check for link time errors.  Accessing a field from a
   // certain class via a certain bytecode may or may not be legal.
   // This call checks to see if an exception may be raised by
   // an access of this field.
   //
   // Usage note: if the same field is accessed multiple times
   // in the same compilation, will_link will need to be checked
   // at each point of access.
   bool will_link(ciInstanceKlass* accessing_klass,
                  Bytecodes::Code bc);
   // Java access flags
   bool is_public      () { return flags().is_public(); }
   bool is_private     () { return flags().is_private(); }
   bool is_protected   () { return flags().is_protected(); }
   bool is_static      () { return flags().is_static(); }
   bool is_final       () { return flags().is_final(); }
   bool is_stable      () { return flags().is_stable(); }
   bool is_volatile    () { return flags().is_volatile(); }
   bool is_transient   () { return flags().is_transient(); }
   bool is_call_site_target() {
     ciInstanceKlass* callsite_klass = CURRENT_ENV->CallSite_klass();
     if (callsite_klass == NULL)
       return false;
     return (holder()->is_subclass_of(callsite_klass) && (name() == ciSymbol::target_name()));
   }
   // Debugging output
   void print();
   void print_name_on(outputStream* st);
 };
 #endif // SHARE_VM_CI_CIFIELD_HPP

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/ci/ciField.hpp@b2ee5dc63353 (annotated)

src/share/vm/ci/ciField.hpp