jdk8-mips64-public/hotspot: src/share/vm/oops/symbol.cpp@55a0da3d420b (annotated)

src/share/vm/oops/symbol.cpp@55a0da3d420b (annotated)

src/share/vm/oops/symbol.cpp

Tue, 26 Nov 2013 14:35:38 +0100

author: sjohanss
date: Tue, 26 Nov 2013 14:35:38 +0100
changeset 6148: 55a0da3d420b
parent 5614: 9758d9f36299
child 6351: f9e35a9dc8c7
permissions: -rw-r--r--

8027675: Full collections with Serial slower in JDK 8 compared to 7u40
Summary: Reduced the number of calls to follow_class_loader and instead marked and pushed the klass holder directly. Also removed unneeded calls to adjust_klass.
Reviewed-by: coleenp, jmasa, mgerdin, tschatzl

 /*
  * Copyright (c) 1997, 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.
  *
  */
 #include "precompiled.hpp"
 #include "classfile/altHashing.hpp"
 #include "classfile/classLoaderData.hpp"
 #include "oops/symbol.hpp"
 #include "runtime/atomic.inline.hpp"
 #include "runtime/os.hpp"
 #include "memory/allocation.inline.hpp"
 #include "memory/resourceArea.hpp"
 Symbol::Symbol(const u1* name, int length, int refcount) {
   _refcount = refcount;
   _length = length;
   _identity_hash = os::random();
   for (int i = 0; i < _length; i++) {
     byte_at_put(i, name[i]);
   }
 }
 void* Symbol::operator new(size_t sz, int len, TRAPS) throw() {
   int alloc_size = size(len)*HeapWordSize;
   address res = (address) AllocateHeap(alloc_size, mtSymbol);
   return res;
 }
 void* Symbol::operator new(size_t sz, int len, Arena* arena, TRAPS) throw() {
   int alloc_size = size(len)*HeapWordSize;
   address res = (address)arena->Amalloc(alloc_size);
   return res;
 }
 void* Symbol::operator new(size_t sz, int len, ClassLoaderData* loader_data, TRAPS) throw() {
   address res;
   int alloc_size = size(len)*HeapWordSize;
   res = (address) Metaspace::allocate(loader_data, size(len), true,
                                       MetaspaceObj::SymbolType, CHECK_NULL);
   return res;
 }
 void Symbol::operator delete(void *p) {
   assert(((Symbol*)p)->refcount() == 0, "should not call this");
   FreeHeap(p);
 }
 // ------------------------------------------------------------------
 // Symbol::equals
 //
 // Compares the symbol with a string of the given length.
 bool Symbol::equals(const char* str, int len) const {
   int l = utf8_length();
   if (l != len) return false;
   while (l-- > 0) {
     if (str[l] != (char) byte_at(l))
       return false;
   }
   assert(l == -1, "we should be at the beginning");
   return true;
 }
 // ------------------------------------------------------------------
 // Symbol::starts_with
 //
 // Tests if the symbol starts with the specified prefix of the given
 // length.
 bool Symbol::starts_with(const char* prefix, int len) const {
   if (len > utf8_length()) return false;
   while (len-- > 0) {
     if (prefix[len] != (char) byte_at(len))
       return false;
   }
   assert(len == -1, "we should be at the beginning");
   return true;
 }
 // ------------------------------------------------------------------
 // Symbol::index_of
 //
 // Finds if the given string is a substring of this symbol's utf8 bytes.
 // Return -1 on failure.  Otherwise return the first index where str occurs.
 int Symbol::index_of_at(int i, const char* str, int len) const {
   assert(i >= 0 && i <= utf8_length(), "oob");
   if (len <= 0)  return 0;
   char first_char = str[0];
   address bytes = (address) ((Symbol*)this)->base();
   address limit = bytes + utf8_length() - len;  // inclusive limit
   address scan = bytes + i;
   if (scan > limit)
     return -1;
   for (; scan <= limit; scan++) {
     scan = (address) memchr(scan, first_char, (limit + 1 - scan));
     if (scan == NULL)
       return -1;  // not found
     assert(scan >= bytes+i && scan <= limit, "scan oob");
     if (memcmp(scan, str, len) == 0)
       return (int)(scan - bytes);
   }
   return -1;
 }
 char* Symbol::as_C_string(char* buf, int size) const {
   if (size > 0) {
     int len = MIN2(size - 1, utf8_length());
     for (int i = 0; i < len; i++) {
       buf[i] = byte_at(i);
     }
     buf[len] = '\0';
   }
   return buf;
 }
 char* Symbol::as_C_string() const {
   int len = utf8_length();
   char* str = NEW_RESOURCE_ARRAY(char, len + 1);
   return as_C_string(str, len + 1);
 }
 char* Symbol::as_C_string_flexible_buffer(Thread* t,
                                                  char* buf, int size) const {
   char* str;
   int len = utf8_length();
   int buf_len = len + 1;
   if (size < buf_len) {
     str = NEW_RESOURCE_ARRAY(char, buf_len);
   } else {
     str = buf;
   }
   return as_C_string(str, buf_len);
 }
 void Symbol::print_symbol_on(outputStream* st) const {
   ResourceMark rm;
   st = st ? st : tty;
   st->print("%s", as_quoted_ascii());
 }
 char* Symbol::as_quoted_ascii() const {
   const char *ptr = (const char *)&_body[0];
   int quoted_length = UTF8::quoted_ascii_length(ptr, utf8_length());
   char* result = NEW_RESOURCE_ARRAY(char, quoted_length + 1);
   UTF8::as_quoted_ascii(ptr, utf8_length(), result, quoted_length + 1);
   return result;
 }
 jchar* Symbol::as_unicode(int& length) const {
   Symbol* this_ptr = (Symbol*)this;
   length = UTF8::unicode_length((char*)this_ptr->bytes(), utf8_length());
   jchar* result = NEW_RESOURCE_ARRAY(jchar, length);
   if (length > 0) {
     UTF8::convert_to_unicode((char*)this_ptr->bytes(), result, length);
   }
   return result;
 }
 const char* Symbol::as_klass_external_name(char* buf, int size) const {
   if (size > 0) {
     char* str    = as_C_string(buf, size);
     int   length = (int)strlen(str);
     // Turn all '/'s into '.'s (also for array klasses)
     for (int index = 0; index < length; index++) {
       if (str[index] == '/') {
         str[index] = '.';
       }
     }
     return str;
   } else {
     return buf;
   }
 }
 const char* Symbol::as_klass_external_name() const {
   char* str    = as_C_string();
   int   length = (int)strlen(str);
   // Turn all '/'s into '.'s (also for array klasses)
   for (int index = 0; index < length; index++) {
     if (str[index] == '/') {
       str[index] = '.';
     }
   }
   return str;
 }
 // Alternate hashing for unbalanced symbol tables.
 unsigned int Symbol::new_hash(jint seed) {
   ResourceMark rm;
   // Use alternate hashing algorithm on this symbol.
   return AltHashing::murmur3_32(seed, (const jbyte*)as_C_string(), utf8_length());
 }
 void Symbol::increment_refcount() {
   // Only increment the refcount if positive.  If negative either
   // overflow has occurred or it is a permanent symbol in a read only
   // shared archive.
   if (_refcount >= 0) {
     Atomic::inc(&_refcount);
     NOT_PRODUCT(Atomic::inc(&_total_count);)
   }
 }
 void Symbol::decrement_refcount() {
   if (_refcount >= 0) {
     Atomic::dec(&_refcount);
 #ifdef ASSERT
     if (_refcount < 0) {
       print();
       assert(false, "reference count underflow for symbol");
     }
 #endif
   }
 }
 void Symbol::print_on(outputStream* st) const {
   if (this == NULL) {
     st->print_cr("NULL");
   } else {
     st->print("Symbol: '");
     print_symbol_on(st);
     st->print("'");
     st->print(" count %d", refcount());
   }
 }
 // The print_value functions are present in all builds, to support the
 // disassembler and error reporting.
 void Symbol::print_value_on(outputStream* st) const {
   if (this == NULL) {
     st->print("NULL");
   } else {
     st->print("'");
     for (int i = 0; i < utf8_length(); i++) {
       st->print("%c", byte_at(i));
     }
     st->print("'");
   }
 }
 // SymbolTable prints this in its statistics
 NOT_PRODUCT(int Symbol::_total_count = 0;)

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/oops/symbol.cpp@55a0da3d420b (annotated)

src/share/vm/oops/symbol.cpp