jdk8-mips64-public/hotspot: src/share/vm/utilities/utf8.cpp@c96030fff130 (annotated)

src/share/vm/utilities/utf8.cpp@c96030fff130 (annotated)

src/share/vm/utilities/utf8.cpp

Thu, 20 Nov 2008 16:56:09 -0800

author: ysr
date: Thu, 20 Nov 2008 16:56:09 -0800
changeset 888: c96030fff130
parent 435: a61af66fc99e
child 1907: c18cbe5936b8
permissions: -rw-r--r--

6684579: SoftReference processing can be made more efficient
Summary: For current soft-ref clearing policies, we can decide at marking time if a soft-reference will definitely not be cleared, postponing the decision of whether it will definitely be cleared to the final reference processing phase. This can be especially beneficial in the case of concurrent collectors where the marking is usually concurrent but reference processing is usually not.
Reviewed-by: jmasa

 /*
  * Copyright 1997-2004 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/_utf8.cpp.incl"
 // Assume the utf8 string is in legal form and has been
 // checked in the class file parser/format checker.
 char* UTF8::next(const char* str, jchar* value) {
   unsigned const char *ptr = (const unsigned char *)str;
   unsigned char ch, ch2, ch3;
   int length = -1;              /* bad length */
   jchar result;
   switch ((ch = ptr[0]) >> 4) {
     default:
     result = ch;
     length = 1;
     break;
   case 0x8: case 0x9: case 0xA: case 0xB: case 0xF:
     /* Shouldn't happen. */
     break;
   case 0xC: case 0xD:
     /* 110xxxxx  10xxxxxx */
     if (((ch2 = ptr[1]) & 0xC0) == 0x80) {
       unsigned char high_five = ch & 0x1F;
       unsigned char low_six = ch2 & 0x3F;
       result = (high_five << 6) + low_six;
       length = 2;
       break;
     }
     break;
   case 0xE:
     /* 1110xxxx 10xxxxxx 10xxxxxx */
     if (((ch2 = ptr[1]) & 0xC0) == 0x80) {
       if (((ch3 = ptr[2]) & 0xC0) == 0x80) {
         unsigned char high_four = ch & 0x0f;
         unsigned char mid_six = ch2 & 0x3f;
         unsigned char low_six = ch3 & 0x3f;
         result = (((high_four << 6) + mid_six) << 6) + low_six;
         length = 3;
       }
     }
     break;
   } /* end of switch */
   if (length <= 0) {
     *value = ptr[0];    /* default bad result; */
     return (char*)(ptr + 1); // make progress somehow
   }
   *value = result;
   // The assert is correct but the .class file is wrong
   // assert(UNICODE::utf8_size(result) == length, "checking reverse computation");
   return (char *)(ptr + length);
 }
 char* UTF8::next_character(const char* str, jint* value) {
   unsigned const char *ptr = (const unsigned char *)str;
   /* See if it's legal supplementary character:
      11101101 1010xxxx 10xxxxxx 11101101 1011xxxx 10xxxxxx */
   if (is_supplementary_character(ptr)) {
     *value = get_supplementary_character(ptr);
     return (char *)(ptr + 6);
   }
   jchar result;
   char* next_ch = next(str, &result);
   *value = result;
   return next_ch;
 }
 // Count bytes of the form 10xxxxxx and deduct this count
 // from the total byte count.  The utf8 string must be in
 // legal form which has been verified in the format checker.
 int UTF8::unicode_length(const char* str, int len) {
   int num_chars = len;
   for (int i = 0; i < len; i++) {
     if ((str[i] & 0xC0) == 0x80) {
       --num_chars;
     }
   }
   return num_chars;
 }
 // Count bytes of the utf8 string except those in form
 // 10xxxxxx which only appear in multibyte characters.
 // The utf8 string must be in legal form and has been
 // verified in the format checker.
 int UTF8::unicode_length(const char* str) {
   int num_chars = 0;
   for (const char* p = str; *p; p++) {
     if (((*p) & 0xC0) != 0x80) {
       num_chars++;
     }
   }
   return num_chars;
 }
 // Writes a jchar a utf8 and returns the end
 static u_char* utf8_write(u_char* base, jchar ch) {
   if ((ch != 0) && (ch <=0x7f)) {
     base[0] = (u_char) ch;
     return base + 1;
   }
   if (ch <= 0x7FF) {
     /* 11 bits or less. */
     unsigned char high_five = ch >> 6;
     unsigned char low_six = ch & 0x3F;
     base[0] = high_five | 0xC0; /* 110xxxxx */
     base[1] = low_six | 0x80;   /* 10xxxxxx */
     return base + 2;
   }
   /* possibly full 16 bits. */
   char high_four = ch >> 12;
   char mid_six = (ch >> 6) & 0x3F;
   char low_six = ch & 0x3f;
   base[0] = high_four | 0xE0; /* 1110xxxx */
   base[1] = mid_six | 0x80;   /* 10xxxxxx */
   base[2] = low_six | 0x80;   /* 10xxxxxx */
   return base + 3;
 }
 void UTF8::convert_to_unicode(const char* utf8_str, jchar* unicode_str, int unicode_length) {
   unsigned char ch;
   const char *ptr = (const char *)utf8_str;
   int index = 0;
   /* ASCII case loop optimization */
   for (; index < unicode_length; index++) {
     if((ch = ptr[0]) > 0x7F) { break; }
     unicode_str[index] = ch;
     ptr = (const char *)(ptr + 1);
   }
   for (; index < unicode_length; index++) {
     ptr = UTF8::next(ptr, &unicode_str[index]);
   }
 }
 // Returns NULL if 'c' it not found. This only works as long
 // as 'c' is an ASCII character
 jbyte* UTF8::strrchr(jbyte* base, int length, jbyte c) {
   assert(length >= 0, "sanity check");
   assert(c >= 0, "does not work for non-ASCII characters");
   // Skip backwards in string until 'c' is found or end is reached
   while(--length >= 0 && base[length] != c);
   return (length < 0) ? NULL : &base[length];
 }
 bool UTF8::equal(jbyte* base1, int length1, jbyte* base2, int length2) {
   // Length must be the same
   if (length1 != length2) return false;
   for (int i = 0; i < length1; i++) {
     if (base1[i] != base2[i]) return false;
   }
   return true;
 }
 bool UTF8::is_supplementary_character(const unsigned char* str) {
   return ((str[0] & 0xFF) == 0xED) && ((str[1] & 0xF0) == 0xA0) && ((str[2] & 0xC0) == 0x80)
       && ((str[3] & 0xFF) == 0xED) && ((str[4] & 0xF0) == 0xB0) && ((str[5] & 0xC0) == 0x80);
 }
 jint UTF8::get_supplementary_character(const unsigned char* str) {
   return 0x10000 + ((str[1] & 0x0f) << 16) + ((str[2] & 0x3f) << 10)
                  + ((str[4] & 0x0f) << 6)  + (str[5] & 0x3f);
 }
 //-------------------------------------------------------------------------------------
 int UNICODE::utf8_size(jchar c) {
   if ((0x0001 <= c) && (c <= 0x007F)) return 1;
   if (c <= 0x07FF) return 2;
   return 3;
 }
 int UNICODE::utf8_length(jchar* base, int length) {
   int result = 0;
   for (int index = 0; index < length; index++) {
     jchar c = base[index];
     if ((0x0001 <= c) && (c <= 0x007F)) result += 1;
     else if (c <= 0x07FF) result += 2;
     else result += 3;
   }
   return result;
 }
 char* UNICODE::as_utf8(jchar* base, int length) {
   int utf8_len = utf8_length(base, length);
   u_char* result = NEW_RESOURCE_ARRAY(u_char, utf8_len + 1);
   u_char* p = result;
   for (int index = 0; index < length; index++) {
     p = utf8_write(p, base[index]);
   }
   *p = '\0';
   assert(p == &result[utf8_len], "length prediction must be correct");
   return (char*) result;
 }
 char* UNICODE::as_utf8(jchar* base, int length, char* buf, int buflen) {
   u_char* p = (u_char*)buf;
   u_char* end = (u_char*)buf + buflen;
   for (int index = 0; index < length; index++) {
     jchar c = base[index];
     if (p + utf8_size(c) >= end) break;      // string is truncated
     p = utf8_write(p, base[index]);
   }
   *p = '\0';
   return buf;
 }
 void UNICODE::convert_to_utf8(const jchar* base, int length, char* utf8_buffer) {
   for(int index = 0; index < length; index++) {
     utf8_buffer = (char*)utf8_write((u_char*)utf8_buffer, base[index]);
   }
   *utf8_buffer = '\0';
 }

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/utilities/utf8.cpp@c96030fff130 (annotated)

src/share/vm/utilities/utf8.cpp