Iterator based CRC32 computation. Fixes issues #388, #414 and

potentially a few other.

Algorithms/IteratorBasedCRC32.h

@@ -0,0 +1,110 @@
+/*
+    open source routing machine
+    Copyright (C) Dennis Luxen, others 2010
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU AFFERO General Public License as published by
+the Free Software Foundation; either version 3 of the License, or
+any later version.
+
+This program 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 for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+or see http://www.gnu.org/licenses/agpl.txt.
+ */
+
+
+#ifndef ITERATORBASEDCRC32_H_
+#define ITERATORBASEDCRC32_H_
+
+#include <boost/crc.hpp>  // for boost::crc_32_type
+#include <iostream>
+
+template<class ContainerT>
+class IteratorbasedCRC32 {
+private:
+    typedef typename ContainerT::iterator ContainerT_iterator;
+    unsigned crc;
+    unsigned slowcrc_table[1<<8];
+
+    typedef boost::crc_optimal<32, 0x1EDC6F41, 0x0, 0x0, true, true> my_crc_32_type;
+    typedef unsigned (IteratorbasedCRC32::*CRC32CFunctionPtr)(char *str, unsigned len, unsigned crc);
+
+    unsigned SoftwareBasedCRC32(char *str, unsigned len, unsigned crc){
+        boost::crc_optimal<32, 0x1EDC6F41, 0x0, 0x0, true, true> CRC32_Processor;
+        CRC32_Processor.process_bytes( str, len);
+        return CRC32_Processor.checksum();
+    }
+    unsigned SSEBasedCRC32( char *str, unsigned len, unsigned crc){
+        unsigned q=len/sizeof(unsigned),
+                r=len%sizeof(unsigned),
+                *p=(unsigned*)str/*, crc*/;
+
+        //crc=0;
+        while (q--) {
+            __asm__ __volatile__(
+                    ".byte 0xf2, 0xf, 0x38, 0xf1, 0xf1;"
+                    :"=S"(crc)
+                     :"0"(crc), "c"(*p)
+            );
+            ++p;
+        }
+
+        str=(char*)p;
+        while (r--) {
+            __asm__ __volatile__(
+                    ".byte 0xf2, 0xf, 0x38, 0xf1, 0xf1;"
+                    :"=S"(crc)
+                     :"0"(crc), "c"(*str)
+            );
+            ++str;
+        }
+        return crc;
+    }
+
+    unsigned cpuid(unsigned functionInput){
+        unsigned eax;
+        unsigned ebx;
+        unsigned ecx;
+        unsigned edx;
+        asm("cpuid" : "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx) : "a" (functionInput));
+        return ecx;
+    }
+
+    CRC32CFunctionPtr detectBestCRC32C(){
+        static const int SSE42_BIT = 20;
+        unsigned ecx = cpuid(1);
+        bool hasSSE42 = ecx & (1 << SSE42_BIT);
+        if (hasSSE42) {
+            std::cout << "using hardware base sse computation" << std::endl;
+            return &IteratorbasedCRC32::SSEBasedCRC32; //crc32 hardware accelarated;
+        } else {
+            std::cout << "using software base sse computation" << std::endl;
+            return &IteratorbasedCRC32::SoftwareBasedCRC32; //crc32cSlicingBy8;
+        }
+    }
+    CRC32CFunctionPtr crcFunction;
+public:
+    IteratorbasedCRC32(): crc(0) {
+        crcFunction = detectBestCRC32C();
+    }
+
+    virtual ~IteratorbasedCRC32() {};
+
+    unsigned operator()( ContainerT_iterator iter, const ContainerT_iterator end) {
+        unsigned crc = 0;
+        while(iter != end) {
+            char * data = (char*)&(*iter);
+            crc =((*this).*(crcFunction))(data, sizeof(typename ContainerT::value_type*), crc);
+            ++iter;
+        }
+        return crc;
+    }
+};
+
+#endif /* ITERATORBASEDCRC32_H_ */

createHierarchy.cpp

@@ -42,7 +42,7 @@ extern "C" {
 #include <string>
 #include <vector>
 
-#include "Algorithms/CRC32.h"
+#include "Algorithms/IteratorBasedCRC32.h"
 #include "Util/OpenMPWrapper.h"
 #include "typedefs.h"
 #include "Contractor/Contractor.h"
@@ -201,9 +201,10 @@ int main (int argc, char *argv[]) {
     WritableGrid * writeableGrid = new WritableGrid();
     writeableGrid->ConstructGrid(nodeBasedEdgeList, ramIndexOut, fileIndexOut);
     delete writeableGrid;
-    CRC32 crc32;
+    IteratorbasedCRC32<DeallocatingVector<EdgeBasedGraphFactory::EdgeBasedNode> > crc32;
-    unsigned crc32OfNodeBasedEdgeList = crc32((char *)&(nodeBasedEdgeList[0]), nodeBasedEdgeList.size()*sizeof(EdgeBasedGraphFactory::EdgeBasedNode));
+    unsigned crc32OfNodeBasedEdgeList = crc32(nodeBasedEdgeList.begin(), nodeBasedEdgeList.end() );
     nodeBasedEdgeList.clear();
+    INFO("CRC32 based checksum is " << crc32OfNodeBasedEdgeList);
 
     /***
      * Contracting the edge-expanded graph