Experiment with prime computation.

src/misc/extra/extraUtilPrime.c

+/**CFile****************************************************************
+
+  FileName    [extraUtilPrime.c]
+
+  SystemName  [ABC: Logic synthesis and verification system.]
+
+  PackageName [extra]
+
+  Synopsis    [Function enumeration.]
+
+  Author      [Alan Mishchenko]
+  
+  Affiliation [UC Berkeley]
+
+  Date        [Ver. 1.0. Started - June 20, 2005.]
+
+  Revision    [$Id: extraUtilPrime.c,v 1.0 2003/02/01 00:00:00 alanmi Exp $]
+
+***********************************************************************/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+#include "misc/vec/vec.h"
+#include "misc/vec/vecHsh.h"
+#include "bool/kit/kit.h"
+
+ABC_NAMESPACE_IMPL_START
+
+////////////////////////////////////////////////////////////////////////
+///                        DECLARATIONS                              ///
+////////////////////////////////////////////////////////////////////////
+
+////////////////////////////////////////////////////////////////////////
+///                     FUNCTION DEFINITIONS                         ///
+////////////////////////////////////////////////////////////////////////
+
+/**Function*************************************************************
+
+  Synopsis    []
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Abc_GenCountDump( Vec_Int_t * vPrimes, int nVars, char * pFileName )
+{
+    FILE * pFile;
+    int i, k, Prime;
+    pFile = fopen( pFileName, "wb" );
+    fprintf( pFile, "# %d prime numbers up to 2^%d generated by ABC on %s\n", Vec_IntSize(vPrimes), nVars, Extra_TimeStamp() );
+    fprintf( pFile, ".i %d\n", nVars );
+    fprintf( pFile, ".o %d\n", 1 );
+    fprintf( pFile, ".p %d\n", Vec_IntSize(vPrimes) );
+    Vec_IntForEachEntry( vPrimes, Prime, i )
+        for ( k = nVars-1; k >= 0; k-- )
+            fprintf( pFile, "%d%s", (Prime >> k)&1, k ? "" : " 1\n" );
+    fprintf( pFile, ".e\n\n" );
+    fclose( pFile );
+}
+
+/**Function*************************************************************
+
+  Synopsis    []
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Abc_GenCountHits1( Vec_Bit_t * vMap, Vec_Int_t * vPrimes, int nVars )
+{
+    abctime clk = Abc_Clock();
+    int i, k, Prime, Count = 0;
+    Vec_IntForEachEntry( vPrimes, Prime, i )
+    {
+        for ( k = 0; k < nVars; k++ )
+            if ( !Vec_BitEntry(vMap, Prime ^ (1<<k)) )
+                Count++;
+    }
+    printf( "Dist1 pairs = %d. ", Count );
+    Abc_PrintTime( 1, "Time", Abc_Clock() - clk );
+}
+Vec_Int_t * Abc_GenPrimes( int nVars )
+{
+    int i, n, nBits = ( 1 << nVars );
+    Vec_Bit_t * vMap = Vec_BitStart( nBits );
+    Vec_Int_t * vPrimes = Vec_IntAlloc( 1000 );
+    for ( n = 2; n < nBits; n++ )
+        if ( !Vec_BitEntry(vMap, n) )
+            for ( i = 2*n; i < nBits; i += n )
+                Vec_BitWriteEntry(vMap, i, 1);
+    for ( n = 2; n < nBits; n++ )
+        if ( !Vec_BitEntry(vMap, n) )
+            Vec_IntPush( vPrimes, n );
+    Abc_GenCountHits1( vMap, vPrimes, nVars );
+    Vec_BitFree( vMap );
+    return vPrimes;
+}
+void Abc_GenPrimesTest()
+{
+    // 54,400,028 primes up to 2^30 can be computed in 22 sec
+    int nVars = 18;
+    Vec_Int_t * vPrimes = Abc_GenPrimes( nVars );
+    Abc_GenCountDump( vPrimes, nVars, "primes18.pla" );
+    //Vec_IntPrint( vPrimes );
+    printf( "Primes up to 2^%d = %d\n", nVars, Vec_IntSize(vPrimes) );
+
+    Vec_IntFree( vPrimes );
+}
+
+////////////////////////////////////////////////////////////////////////
+///                       END OF FILE                                ///
+////////////////////////////////////////////////////////////////////////
+
+
+ABC_NAMESPACE_IMPL_END
+