Tornado: when dictsize increased, increase hashsize in the same propo…

…rtion git-svn-id: https://freearc.svn.sourceforge.net/svnroot/freearc@114 3a4f7f31-9599-433d-91b1-573e8b61252c
abandonware · Feb 26, 2009 · 7c80018 · 7c80018
1 parent 5a1a316
commit 7c80018
Show file tree

Hide file tree

Showing 2 changed files with 25 additions and 4 deletions.
diff --git a/Compression/Common.h b/Compression/Common.h
@@ -164,7 +164,7 @@ static inline int  file_exists (CFILENAME name) {return _taccess(name,0) == 0;}
 // Number of 100 nanosecond units from 01.01.1601 to 01.01.1970
 #define EPOCH_BIAS    116444736000000000ull
 
-inline void WINAPI UnixTimeToFileTime( time_t time, FILETIME* ft )
+static inline void WINAPI UnixTimeToFileTime( time_t time, FILETIME* ft )
 {
   *(uint64*)ft = EPOCH_BIAS + time * 10000000ull;
 }
@@ -484,6 +484,17 @@ static inline MemSize rounddown_to_power_of (MemSize n, MemSize base)
     return result;
 }
 
+// Ýòà ïðîöåäóðà îêðóãëÿåò ÷èñëî ê ëîãàðèôìè÷åñêè áëèæàéøåé ñòåïåíè
+// áàçû, íàïðèìåð f(9,2)=8  f(15,2)=16
+static inline MemSize round_to_nearest_power_of (MemSize n, MemSize base)
+{
+    MemSize result;
+    uint64 nn = uint64(n)*n/base;
+    if (nn==0)  return 1;
+    for (result=base; (nn/=base*base) != 0; result *= base);
+    return result;
+}
+
 // Çàìåíèòü ñèìâîëû èç ìíîæåñòâà from íà ñèìâîë to
 static inline char *replace (char *str, char* from, char to)
 {

diff --git a/Compression/Tornado/C_Tornado.cpp b/Compression/Tornado/C_Tornado.cpp
@@ -28,12 +28,22 @@ int TORNADO_METHOD::compress (CALLBACK_FUNC *callback, void *auxdata)
   return tor_compress (m, callback, auxdata);
 }
 
-// Óñòàíîâèòü ðàçìåð ñëîâàðÿ è óìåíüøèòü ðàçìåð õýøà, åñëè îí ñëèøêîì âåëèê äëÿ òàêîãî ìàëåíüêîãî áëîêà
+// Óñòàíîâèòü ðàçìåð ñëîâàðÿ è îòêîððåêòèðîâàòü ðàçìåð õåøà
 void TORNADO_METHOD::SetDictionary (MemSize dict)
 {
   if (dict>0) {
-    m.buffer   = dict;
-    m.hashsize = mymin (m.hashsize/sizeof(void*), 1<<(lb(m.buffer-1)+1)) * sizeof(void*);
+    if (dict < m.buffer)
+      // Ïðè óìåíüøåíèè ñëîâàðÿ: óìåíüøèòü ðàçìåð õýøà, åñëè îí ñëèøêîì âåëèê äëÿ òàêîãî ìàëåíüêîãî áëîêà
+      m.hashsize  =  sizeof(PtrVal)  *  mymin (m.hashsize/sizeof(PtrVal), roundup_to_power_of(dict,2));
+    else
+      // Ïðè óâåëè÷åíèè ñëîâàðÿ: ïðîïîðöèîíàëüíî óâåëè÷èòü ðàçìåð õåøà
+      if (m.hashsize > 1*mb)
+      {
+        if (m.hashsize<8*mb && m.hashsize<m.buffer/2)   m.hashsize = m.buffer/2;  // Âî-ïåðâûõ, óâåëè÷èì ðàçìåð õåøà, åñëè îí áûë ïîäîãíàí ïîä êåø Core2
+        uint h  =  mymin (uint64(dict) / (m.buffer/64) * (m.hashsize/64),  2*gb);  // Èäåàëüíûé ðàçìåð íîâîãî õåøà
+        m.hashsize = mymin (round_to_nearest_power_of(h / m.hash_row_width, 2) * m.hash_row_width,  2*gb);  // Îêðóãëèì ðàçìåð õåøà ñ ó÷¸òîì row_width
+      }
+    m.buffer = dict;
   }
 }