Adding switch 'buffer -p' to enable buffing of the primary inputs.

src/map/scl/scl.c

@@ -558,15 +558,16 @@ int Scl_CommandBuffer( Abc_Frame_t * pAbc, int argc, char ** argv )
 {
     Abc_Ntk_t * pNtk = Abc_FrameReadNtk(pAbc);
     Abc_Ntk_t * pNtkRes;
-    int FanMin, FanMax, fUseInvs;
+    int FanMin, FanMax, fUseInvs, fBufPis;
     int c, fVerbose;
     int fOldAlgo = 0;
     FanMin   =  6;
     FanMax   = 14;
     fUseInvs =  0;
+    fBufPis  =  0;
     fVerbose =  0;
     Extra_UtilGetoptReset();
-    while ( ( c = Extra_UtilGetopt( argc, argv, "NMaivh" ) ) != EOF )
+    while ( ( c = Extra_UtilGetopt( argc, argv, "NMaipvh" ) ) != EOF )
     {
         switch ( c )
         {
@@ -598,6 +599,9 @@ int Scl_CommandBuffer( Abc_Frame_t * pAbc, int argc, char ** argv )
         case 'i':
             fUseInvs ^= 1;
             break;
+        case 'p':
+            fBufPis ^= 1;
+            break;
         case 'v':
             fVerbose ^= 1;
             break;
@@ -623,7 +627,7 @@ int Scl_CommandBuffer( Abc_Frame_t * pAbc, int argc, char ** argv )
     if ( fOldAlgo )
         pNtkRes = Abc_SclPerformBuffering( pNtk, FanMax, fUseInvs, fVerbose );
     else
-        pNtkRes = Abc_SclBufPerform( pNtk, FanMin, FanMax, fVerbose );
+        pNtkRes = Abc_SclBufPerform( pNtk, FanMin, FanMax, fBufPis, fVerbose );
     if ( pNtkRes == NULL )
     {
         Abc_Print( -1, "The command has failed.\n" );
@@ -634,12 +638,13 @@ int Scl_CommandBuffer( Abc_Frame_t * pAbc, int argc, char ** argv )
     return 0;
 
 usage:
-    fprintf( pAbc->Err, "usage: buffer [-NM num] [-aivh]\n" );
+    fprintf( pAbc->Err, "usage: buffer [-NM num] [-aipvh]\n" );
     fprintf( pAbc->Err, "\t           performs buffering of the mapped network\n" );
     fprintf( pAbc->Err, "\t-N <num> : the min fanout considered by the algorithm [default = %d]\n", FanMin );
     fprintf( pAbc->Err, "\t-M <num> : the max allowed fanout count of node/buffer [default = %d]\n", FanMax );
     fprintf( pAbc->Err, "\t-a       : toggle using old algorithm [default = %s]\n", fOldAlgo? "yes": "no" );
     fprintf( pAbc->Err, "\t-i       : toggle using interters instead of buffers [default = %s]\n", fUseInvs? "yes": "no" );
+    fprintf( pAbc->Err, "\t-p       : toggle buffering primary inputs [default = %s]\n", fBufPis? "yes": "no" );
     fprintf( pAbc->Err, "\t-v       : toggle printing verbose information [default = %s]\n", fVerbose? "yes": "no" );
     fprintf( pAbc->Err, "\t-h       : print the command usage\n");
     return 1;

src/map/scl/sclBuffer.c

@@ -36,6 +36,7 @@ struct Buf_Man_t_
     // parameters
     int            nFanMin;   // the smallest fanout count to consider
     int            nFanMax;   // the largest fanout count allowed off CP
+    int            fBufPis;   // enables buffing of the combinational inputs
     // internal deta
     Abc_Ntk_t *    pNtk;      // logic network
     Vec_Int_t *    vOffsets;  // offsets into edge delays
@@ -372,7 +373,7 @@ void Abc_BufCreateEdges( Buf_Man_t * p, Abc_Obj_t * pObj )
 }
 void Abc_BufAddToQue( Buf_Man_t * p, Abc_Obj_t * pObj )
 {
-    if ( Abc_ObjFanoutNum(pObj) < p->nFanMin )
+    if ( Abc_ObjFanoutNum(pObj) < p->nFanMin || (!p->fBufPis && Abc_ObjIsCi(pObj)) )
         return;
     Vec_FltWriteEntry( p->vCounts, Abc_ObjId(pObj), Abc_ObjFanoutNum(pObj) );
     if ( Vec_QueIsMember(p->vQue, Abc_ObjId(pObj)) )
@@ -484,7 +485,7 @@ void Abc_BufUpdateDep( Buf_Man_t * p, Abc_Obj_t * pObj )
   SeeAlso     []
 
 ***********************************************************************/
-Buf_Man_t * Buf_ManStart( Abc_Ntk_t * pNtk, int FanMin, int FanMax )
+Buf_Man_t * Buf_ManStart( Abc_Ntk_t * pNtk, int FanMin, int FanMax, int fBufPis )
 {
     Buf_Man_t * p;
     Abc_Obj_t * pObj;
@@ -494,6 +495,7 @@ Buf_Man_t * Buf_ManStart( Abc_Ntk_t * pNtk, int FanMin, int FanMax )
     p->pNtk      = pNtk;
     p->nFanMin   = FanMin;
     p->nFanMax   = FanMax;
+    p->fBufPis   = fBufPis;
     // allocate arrays
     p->nObjStart = Abc_NtkObjNumMax(p->pNtk);
     p->nObjAlloc = (6 * Abc_NtkObjNumMax(p->pNtk) / 3) + 100;
@@ -793,10 +795,10 @@ printf( "Doing nothing\n" );
 //    if ( DelayMax != p->DelayMax )
 //        printf( "%d (%.2f)  ", p->DelayMax, 1.0 * p->DelayMax * p->DelayInv / BUF_SCALE );
 }
-Abc_Ntk_t * Abc_SclBufPerform( Abc_Ntk_t * pNtk, int FanMin, int FanMax, int fVerbose )
+Abc_Ntk_t * Abc_SclBufPerform( Abc_Ntk_t * pNtk, int FanMin, int FanMax, int fBufPis, int fVerbose )
 {
     Abc_Ntk_t * pNew;
-    Buf_Man_t * p = Buf_ManStart( pNtk, FanMin, FanMax );
+    Buf_Man_t * p = Buf_ManStart( pNtk, FanMin, FanMax, fBufPis );
     int i, Limit = ABC_INFINITY;
     for ( i = 0; i < Limit && Vec_QueSize(p->vQue); i++ )
         Abc_BufPerformOne( p, Vec_QuePop(p->vQue), fVerbose );

src/map/scl/sclSize.h

@@ -389,7 +389,7 @@ static inline void Abc_SclDumpStats( SC_Man * p, char * pFileName, abctime Time
 extern Abc_Ntk_t *   Abc_SclUnBufferPerform( Abc_Ntk_t * pNtk, int fVerbose );
 extern int           Abc_SclCheckNtk( Abc_Ntk_t * p, int fVerbose );
 extern Abc_Ntk_t *   Abc_SclPerformBuffering( Abc_Ntk_t * p, int Degree, int fUseInvs, int fVerbose );
-extern Abc_Ntk_t *   Abc_SclBufPerform( Abc_Ntk_t * pNtk, int FanMin, int FanMax, int fVerbose );
+extern Abc_Ntk_t *   Abc_SclBufPerform( Abc_Ntk_t * pNtk, int FanMin, int FanMax, int fBufPis, int fVerbose );
 /*=== sclDnsize.c ===============================================================*/
 extern void          Abc_SclDnsizePerform( SC_Lib * pLib, Abc_Ntk_t * pNtk, SC_SizePars * pPars );
 /*=== sclLoad.c ===============================================================*/