1 /*
   2  * Copyright (c) 1998, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "adlc.hpp"
  26 
  27 void* Chunk::operator new(size_t requested_size, size_t length) throw() {
  28   return CHeapObj::operator new(requested_size + length);
  29 }
  30 
  31 void  Chunk::operator delete(void* p, size_t length) {
  32   CHeapObj::operator delete(p);
  33 }
  34 
  35 Chunk::Chunk(size_t length) {
  36   _next = NULL;         // Chain on the linked list
  37   _len  = length;       // Save actual size
  38 }
  39 
  40 //------------------------------chop-------------------------------------------
  41 void Chunk::chop() {
  42   Chunk *k = this;
  43   while( k ) {
  44     Chunk *tmp = k->_next;
  45     // clear out this chunk (to detect allocation bugs)
  46     memset(k, 0xBE, k->_len);
  47     free(k);                    // Free chunk (was malloc'd)
  48     k = tmp;
  49   }
  50 }
  51 
  52 void Chunk::next_chop() {
  53   _next->chop();
  54   _next = NULL;
  55 }
  56 
  57 //------------------------------Arena------------------------------------------
  58 Arena::Arena( size_t init_size ) {
  59   init_size = (init_size+3) & ~3;
  60   _first = _chunk = new (init_size) Chunk(init_size);
  61   _hwm = _chunk->bottom();      // Save the cached hwm, max
  62   _max = _chunk->top();
  63   set_size_in_bytes(init_size);
  64 }
  65 
  66 Arena::Arena() {
  67   _first = _chunk = new (Chunk::init_size) Chunk(Chunk::init_size);
  68   _hwm = _chunk->bottom();      // Save the cached hwm, max
  69   _max = _chunk->top();
  70   set_size_in_bytes(Chunk::init_size);
  71 }
  72 
  73 Arena::Arena( Arena *a )
  74 : _chunk(a->_chunk), _hwm(a->_hwm), _max(a->_max), _first(a->_first) {
  75   set_size_in_bytes(a->size_in_bytes());
  76 }
  77 
  78 //------------------------------used-------------------------------------------
  79 // Total of all Chunks in arena
  80 size_t Arena::used() const {
  81   size_t sum = _chunk->_len - (_max-_hwm); // Size leftover in this Chunk
  82   Chunk *k = _first;
  83   while( k != _chunk) {         // Whilst have Chunks in a row
  84     sum += k->_len;             // Total size of this Chunk
  85     k = k->_next;               // Bump along to next Chunk
  86   }
  87   return sum;                   // Return total consumed space.
  88 }
  89 
  90 //------------------------------grow-------------------------------------------
  91 // Grow a new Chunk
  92 void* Arena::grow( size_t x ) {
  93   // Get minimal required size.  Either real big, or even bigger for giant objs
  94   size_t len = max(x, Chunk::size);
  95 
  96   Chunk *k = _chunk;            // Get filled-up chunk address
  97   _chunk = new (len) Chunk(len);
  98 
  99   if( k ) k->_next = _chunk;    // Append new chunk to end of linked list
 100   else _first = _chunk;
 101   _hwm  = _chunk->bottom();     // Save the cached hwm, max
 102   _max =  _chunk->top();
 103   set_size_in_bytes(size_in_bytes() + len);
 104   void* result = _hwm;
 105   _hwm += x;
 106   return result;
 107 }
 108 
 109 //------------------------------calloc-----------------------------------------
 110 // Allocate zeroed storage in Arena
 111 void *Arena::Acalloc( size_t items, size_t x ) {
 112   size_t z = items*x;   // Total size needed
 113   void *ptr = Amalloc(z);       // Get space
 114   memset( ptr, 0, z );          // Zap space
 115   return ptr;                   // Return space
 116 }
 117 
 118 //------------------------------realloc----------------------------------------
 119 // Reallocate storage in Arena.
 120 void *Arena::Arealloc( void *old_ptr, size_t old_size, size_t new_size ) {
 121   char *c_old = (char*)old_ptr; // Handy name
 122   // Stupid fast special case
 123   if( new_size <= old_size ) {  // Shrink in-place
 124     if( c_old+old_size == _hwm) // Attempt to free the excess bytes
 125       _hwm = c_old+new_size;    // Adjust hwm
 126     return c_old;
 127   }
 128 
 129   // See if we can resize in-place
 130   if( (c_old+old_size == _hwm) &&       // Adjusting recent thing
 131       (c_old+new_size <= _max) ) {      // Still fits where it sits
 132     _hwm = c_old+new_size;      // Adjust hwm
 133     return c_old;               // Return old pointer
 134   }
 135 
 136   // Oops, got to relocate guts
 137   void *new_ptr = Amalloc(new_size);
 138   memcpy( new_ptr, c_old, old_size );
 139   Afree(c_old,old_size);        // Mostly done to keep stats accurate
 140   return new_ptr;
 141 }
 142 
 143 //------------------------------reset------------------------------------------
 144 // Reset this Arena to empty, and return this Arenas guts in a new Arena.
 145 Arena *Arena::reset(void) {
 146   Arena *a = new Arena(this);   // New empty arena
 147   _first = _chunk = NULL;       // Normal, new-arena initialization
 148   _hwm = _max = NULL;
 149   return a;                     // Return Arena with guts
 150 }
 151 
 152 //------------------------------contains---------------------------------------
 153 // Determine if pointer belongs to this Arena or not.
 154 bool Arena::contains( const void *ptr ) const {
 155   if( (void*)_chunk->bottom() <= ptr && ptr < (void*)_hwm )
 156     return true;                // Check for in this chunk
 157   for( Chunk *c = _first; c; c = c->_next )
 158     if( (void*)c->bottom() <= ptr && ptr < (void*)c->top())
 159       return true;              // Check for every chunk in Arena
 160   return false;                 // Not in any Chunk, so not in Arena
 161 }
 162 
 163 //-----------------------------------------------------------------------------
 164 // CHeapObj
 165 
 166 void* CHeapObj::operator new(size_t size) throw() {
 167   return (void *) malloc(size);
 168 }
 169 
 170 void CHeapObj::operator delete(void* p){
 171  free(p);
 172 }