Disjoint-support decomposition with cofactoring and boolean difference analysis

from V. Callegaro, F. S. Marranghello, M. G. A. Martins, R. P. Ribas and A. I. Reis,
entitled "Bottom-up disjoint-support decomposition based on cofactor and boolean difference analysis" presented in ICCD'15.

Makefile

@@ -22,7 +22,7 @@ MODULES := \
 	src/misc/mem src/misc/bar src/misc/bbl src/misc/parse \
 	src/opt/cut src/opt/fxu src/opt/fxch src/opt/rwr src/opt/mfs src/opt/sim \
 	src/opt/ret src/opt/fret src/opt/res src/opt/lpk src/opt/nwk src/opt/rwt \
-	src/opt/cgt src/opt/csw src/opt/dar src/opt/dau src/opt/sfm \
+	src/opt/cgt src/opt/csw src/opt/dar src/opt/dau src/opt/dsc src/opt/sfm \
 	src/sat/bsat src/sat/csat src/sat/msat src/sat/psat src/sat/cnf src/sat/bmc \
 	src/bool/bdc src/bool/deco src/bool/dec src/bool/kit src/bool/lucky \
 	src/bool/rsb src/bool/rpo \

src/base/abci/abc.c

@@ -6212,6 +6212,9 @@ usage:
     Abc_Print( -2, "\t               3: disjoint-support decomposition with cofactoring\n" );
     Abc_Print( -2, "\t               4: updated disjoint-support decomposition with cofactoring\n" );
     Abc_Print( -2, "\t               5: enumerating decomposable variable sets\n" );
+    Abc_Print( -2, "\t               6: disjoint-support decomposition with cofactoring and boolean difference analysis\n" );
+    Abc_Print( -2, "\t                  from V. Callegaro, F. S. Marranghello, M. G. A. Martins, R. P. Ribas and A. I. Reis,\n");
+    Abc_Print( -2, "\t                  \"Bottom-up disjoint-support decomposition based on cofactor and boolean difference analysis,\" ICCD'15.\n" );
     Abc_Print( -2, "\t-N <num> : the number of support variables (binary files only) [default = unused]\n" );
     Abc_Print( -2, "\t-v       : toggle verbose printout [default = %s]\n", fVerbose? "yes": "no" );
     Abc_Print( -2, "\t-h       : print the command usage\n");

src/base/abci/abcDec.c

@@ -26,6 +26,7 @@
 #include "bool/kit/kit.h"
 #include "opt/dau/dau.h"
 #include "misc/util/utilTruth.h"
+#include "opt/dsc/dsc.h"
 
 ABC_NAMESPACE_IMPL_START
 
@@ -484,6 +485,8 @@ void Abc_TruthDecPerform( Abc_TtStore_t * p, int DecType, int fVerbose )
         pAlgoName = "fast DSD";
     else if ( DecType == 5 )
         pAlgoName = "analysis";
+    else if ( DecType == 6 )
+            pAlgoName = "DSD ICCD'15";
 
     if ( pAlgoName )
         printf( "Applying %-10s to %8d func%s of %2d vars...  ",  
@@ -577,6 +580,23 @@ void Abc_TruthDecPerform( Abc_TtStore_t * p, int DecType, int fVerbose )
             if ( fVerbose )
                 printf( "\n" );
         }
+    } else if ( DecType == 6 )
+    {
+        char pDsd[DSC_MAX_STR];
+        /* memory pool with a capacity of storing 3*nVars
+        truth-tables for negative and positive cofactors and
+        the boolean difference for each input variable */
+        word *mem_pool = Dsc_alloc_pool(p->nVars);
+        for ( i = 0; i < p->nFuncs; i++ )
+        {
+            if ( fVerbose )
+                printf( "%7d :      ", i );
+            Dsc_Decompose(p->pFuncs[i], p->nVars, pDsd, mem_pool);
+            if ( fVerbose )
+                printf( "%s\n", pDsd[0] ? pDsd : "NULL");
+            nNodes += Dsc_CountAnds( pDsd );
+        }
+        Dsc_free_pool(mem_pool);
     }
     else assert( 0 );
 
@@ -629,7 +649,7 @@ int Abc_DecTest( char * pFileName, int DecType, int nVarNum, int fVerbose )
         printf( "Using truth tables from file \"%s\"...\n", pFileName );
     if ( DecType == 0 )
         { if ( nVarNum < 0 ) Abc_TtStoreTest( pFileName ); }
-    else if ( DecType >= 1 && DecType <= 5 )
+    else if ( DecType >= 1 && DecType <= 6 )
         Abc_TruthDecTest( pFileName, DecType, nVarNum, fVerbose );
     else
         printf( "Unknown decomposition type value (%d).\n", DecType );

src/opt/dsc/dsc.h

+/**CFile****************************************************************
+
+  FileName    [dsc.h]
+
+  SystemName  [ABC: Logic synthesis and verification system.]
+
+  PackageName [Disjoint support decomposition - ICCD'15]
+
+  Synopsis    [Disjoint-support decomposition with cofactoring and boolean difference analysis
+               from V. Callegaro, F. S. Marranghello, M. G. A. Martins, R. P. Ribas and A. I. Reis,
+               "Bottom-up disjoint-support decomposition based on cofactor and boolean difference analysis," ICCD'15]
+
+  Author      [Vinicius Callegaro, Mayler G. A. Martins, Felipe S. Marranghello, Renato P. Ribas and Andre I. Reis]
+
+  Affiliation [UFRGS - Federal University of Rio Grande do Sul - Brazil]
+
+  Date        [Ver. 1.0. Started - October 24, 2014.]
+
+  Revision    [$Id: dsc.h,v 1.00 2014/10/24 00:00:00 vcallegaro Exp $]
+
+***********************************************************************/
+
+#ifndef ABC__DSC___h
+#define ABC__DSC___h
+
+
+////////////////////////////////////////////////////////////////////////
+///                          INCLUDES                                ///
+////////////////////////////////////////////////////////////////////////
+#include <stdio.h>
+#include <string.h>
+#include "misc/util/abc_global.h"
+
+////////////////////////////////////////////////////////////////////////
+///                         PARAMETERS                               ///
+////////////////////////////////////////////////////////////////////////
+
+ABC_NAMESPACE_HEADER_START
+
+#define DSC_MAX_VAR        16 // should be 6 or more, i.e. DSC_MAX_VAR >= 6
+#define DSC_MAX_STR        DSC_MAX_VAR << 2 // DSC_MAX_VAR * 4
+
+////////////////////////////////////////////////////////////////////////
+///                         BASIC TYPES                              ///
+////////////////////////////////////////////////////////////////////////
+
+////////////////////////////////////////////////////////////////////////
+///                      MACRO DEFINITIONS                           ///
+////////////////////////////////////////////////////////////////////////
+
+////////////////////////////////////////////////////////////////////////
+///                    FUNCTION DECLARATIONS                         ///
+////////////////////////////////////////////////////////////////////////
+
+/*=== dsc.c ==========================================================*/
+
+/**
+ * memory allocator with a capacity of storing 3*nVars
+ * truth-tables for negative and positive cofactors and
+ * the boolean difference for each input variable
+ */
+extern word * Dsc_alloc_pool(int nVars);
+
+/**
+ * This method implements the paper proposed by V. Callegaro, F. S. Marranghello, M. G. A. Martins, R. P. Ribas and A. I. Reis,
+ * entitled "Bottom-up disjoint-support decomposition based on cofactor and boolean difference analysis", presented at ICCD 2015.
+ * pTruth: pointer for the truth table representing the target function.
+ * nVarsInit: the number of variables of the truth table of the target function.
+ * pRes: pointer for storing the resulting decomposition, whenever a decomposition can be found.
+ * pool: NULL or a pointer for with a capacity of storing 3*nVars truth-tables. IF NULL, the function will allocate and free the memory of each call.
+ * (the results presented on ICCD paper are running this method with NULL for the memory pool).
+ * The method returns 0 if a full decomposition was found and a negative value otherwise.
+ */
+extern int Dsc_Decompose(word * pTruth, const int nVarsInit, char * const pRes, word *pool);
+
+/**
+ * just free the memory pool
+ */
+extern void Dsc_free_pool(word * pool);
+
+int * Dsc_ComputeMatches( char * p );
+int Dsc_CountAnds_rec( char * pStr, char ** p, int * pMatches );
+extern int Dsc_CountAnds( char * pDsd );
+
+ABC_NAMESPACE_HEADER_END
+
+#endif
+
+////////////////////////////////////////////////////////////////////////
+///                       END OF FILE                                ///
+////////////////////////////////////////////////////////////////////////

src/opt/dsc/module.make

+SRC +=    src/opt/dsc/dsc.c