Adding delay-driven LUT decomposition to &if

src/aig/gia/giaIf.c

@@ -1424,6 +1424,90 @@ int Gia_ManFromIfLogicNode( void * pIfMan, Gia_Man_t * pNew, int iObj, Vec_Int_t
     return iObjLit3;
 }
 
+/**Function*************************************************************
+
+  Synopsis    [Implements delay-driven decomposition of the cut.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Gia_ManFromIfLogicHop( Gia_Man_t * pNew, If_Man_t * pIfMan, If_Cut_t * pCutBest, Vec_Int_t * vLeaves, Vec_Int_t * vLeavesTemp, Vec_Int_t * vCover, Vec_Int_t * vMapping, Vec_Int_t * vMapping2 )
+{
+    word * pTruth = If_CutTruthW(pIfMan, pCutBest);
+    unsigned char decompArray[92];
+    int val;
+
+    assert( pCutBest->nLeaves > pIfMan->pPars->nLutDecSize );
+
+    unsigned delayProfile = pCutBest->decDelay;
+    val = acd_decompose( pTruth, pCutBest->nLeaves, pIfMan->pPars->nLutDecSize, &(delayProfile), decompArray );
+    assert( val == 0 );
+
+    // convert the LUT-structure into a set of logic nodes in Gia_Man_t 
+    unsigned char bytes_check = decompArray[0];
+    assert( bytes_check <= 92 );
+
+    int byte_p = 2;
+    unsigned char i, j, k, num_fanins, num_words, num_bytes;
+    int iObjLits[5];
+    int fanin;
+    word *tt;
+
+    for ( i = 0; i < decompArray[1]; ++i )
+    {
+        num_fanins = decompArray[byte_p++];
+        Vec_IntClear( vLeavesTemp );
+        for ( j = 0; j < num_fanins; ++j )
+        {
+            fanin = (int)decompArray[byte_p++];
+            if ( fanin < If_CutLeaveNum(pCutBest) )
+            {
+                Vec_IntPush( vLeavesTemp, Vec_IntEntry(vLeaves, fanin) );
+            }
+            else
+            {
+                Vec_IntPush( vLeavesTemp, iObjLits[fanin - If_CutLeaveNum(pCutBest)] );
+            }
+        }
+
+        /* extract the truth table */
+        tt = pIfMan->puTempW;
+        num_words = ( num_fanins <= 6 ) ? 1 : ( 1 << ( num_fanins - 6 ) );
+        num_bytes = ( num_fanins <= 3 ) ? 1 : ( 1 << ( Abc_MinInt( (int)num_fanins, 6 ) - 3 ) );
+        for ( j = 0; j < num_words; ++j )
+        {
+            tt[j] = 0;
+            for ( k = 0; k < num_bytes; ++k )
+            {
+                tt[j] |= ( (word)(decompArray[byte_p++]) ) << ( k << 3 );
+            }
+        }
+
+        /* extend truth table if size < 5 */
+        assert( num_fanins != 1 );
+        if ( num_fanins == 2 )
+        {
+            tt[0] |= tt[0] << 4;
+        }
+        while ( num_bytes < 4 )
+        {
+            tt[0] |= tt[0] << ( num_bytes << 3 );
+            num_bytes <<= 1;
+        }
+
+        iObjLits[i] = Gia_ManFromIfLogicCreateLut( pNew, tt, vLeavesTemp, vCover, vMapping, vMapping2 );
+    }
+
+    /* check correct read */
+    assert( byte_p == decompArray[0] );
+
+    return iObjLits[i-1];
+}
+
 /**Function*************************************************************
 
   Synopsis    [Recursively derives the local AIG for the cut.]
@@ -1907,7 +1991,7 @@ Gia_Man_t * Gia_ManFromIfLogic( If_Man_t * pIfMan )
             if ( !pIfMan->pPars->fUseTtPerm && !pIfMan->pPars->fDelayOpt && !pIfMan->pPars->fDelayOptLut && !pIfMan->pPars->fDsdBalance && 
                  !pIfMan->pPars->pLutStruct && !pIfMan->pPars->fUserRecLib && !pIfMan->pPars->fUserSesLib && !pIfMan->pPars->nGateSize && 
                  !pIfMan->pPars->fEnableCheck75 && !pIfMan->pPars->fEnableCheck75u && !pIfMan->pPars->fEnableCheck07 && !pIfMan->pPars->fUseDsdTune && 
-                 !pIfMan->pPars->fUseCofVars && !pIfMan->pPars->fUseAndVars && !pIfMan->pPars->fUseCheck1 && !pIfMan->pPars->fUseCheck2 )
+                 !pIfMan->pPars->fUseCofVars && !pIfMan->pPars->fUseAndVars && !pIfMan->pPars->fUseCheck1 && !pIfMan->pPars->fUseCheck2 && !pIfMan->pPars->fUserLutDec )
                 If_CutRotatePins( pIfMan, pCutBest );
             // collect leaves of the best cut
             Vec_IntClear( vLeaves );
@@ -1959,6 +2043,10 @@ Gia_Man_t * Gia_ManFromIfLogic( If_Man_t * pIfMan )
             {
                 pIfObj->iCopy = Gia_ManFromIfLogicCofVars( pNew, pIfMan, pCutBest, vLeaves, vLeaves2, vCover, vMapping, vMapping2 );
             }
+            else if ( pIfMan->pPars->fUserLutDec && (int)pCutBest->nLeaves > pIfMan->pPars->nLutDecSize )
+            {
+                pIfObj->iCopy = Gia_ManFromIfLogicHop( pNew, pIfMan, pCutBest, vLeaves, vLeaves2, vCover, vMapping, vMapping2 );
+            }
             else if ( (pIfMan->pPars->fDeriveLuts && pIfMan->pPars->fTruth) || pIfMan->pPars->fUseDsd || pIfMan->pPars->fUseTtPerm || pIfMan->pPars->pFuncCell2 )
             {
                 word * pTruth = If_CutTruthW(pIfMan, pCutBest);

src/base/abci/abc.c

@@ -40412,7 +40412,7 @@ int Abc_CommandAbc9If( Abc_Frame_t * pAbc, int argc, char ** argv )
     }
     pPars->pLutLib = (If_LibLut_t *)pAbc->pLibLut;
     Extra_UtilGetoptReset();
-    while ( ( c = Extra_UtilGetopt( argc, argv, "KCFAGRDEWSJTXYqalepmrsdbgxyofuijkztncvwh" ) ) != EOF )
+    while ( ( c = Extra_UtilGetopt( argc, argv, "KCFAGRDEWSJTXYZqalepmrsdbgxyofuijkztncvwh" ) ) != EOF )
     {
         switch ( c )
         {
@@ -40579,6 +40579,18 @@ int Abc_CommandAbc9If( Abc_Frame_t * pAbc, int argc, char ** argv )
                 goto usage;
             }
             break;
+        case 'Z':
+            if ( globalUtilOptind >= argc )
+            {
+                Abc_Print( -1, "Command line switch \"-Z\" should be followed by a positive integer 3, 4, 5, or 6.\n" );
+                goto usage;
+            }
+            pPars->nLutDecSize = atoi(argv[globalUtilOptind]);
+            pPars->fUserLutDec = 1;
+            globalUtilOptind++;
+            if ( pPars->nLutDecSize < 3 || pPars->nLutDecSize > 6 )
+                goto usage;
+            break;
         case 'q':
             pPars->fPreprocess ^= 1;
             break;
@@ -40825,6 +40837,25 @@ int Abc_CommandAbc9If( Abc_Frame_t * pAbc, int argc, char ** argv )
         pPars->nLutDecSize = pPars->pLutStruct[0] - '0';
     }
 
+    if ( pPars->fUserLutDec )
+    {
+        if ( pPars->nLutDecSize == 0 )
+        {
+            Abc_Print( -1, "LUT decomposition size (%d) must be set.\n", pPars->nLutDecSize );
+            return 1;
+        }
+        if ( pPars->nLutDecSize >= pPars->nLutSize )
+        {
+            Abc_Print( -1, "LUT size (%d) must be greater than the LUT decomposition size (%d).\n", pPars->nLutSize, pPars->nLutDecSize );
+            return 1;
+        }
+        if ( pPars->nLutSize < 4 || pPars->nLutSize > 11 )
+        {
+            Abc_Print( -1, "This feature only works for [4;11]-LUTs.\n" );
+            return 1;
+        }
+    }
+
     if ( pPars->fUse34Spec )
     {
         pPars->fTruth    = 1;
@@ -40850,7 +40881,7 @@ int Abc_CommandAbc9If( Abc_Frame_t * pAbc, int argc, char ** argv )
         pPars->pLutLib     =  NULL;
     }
     // modify for delay optimization
-    if ( pPars->fDelayOpt || pPars->fDsdBalance || pPars->fDelayOptLut )
+    if ( pPars->fDelayOpt || pPars->fDsdBalance || pPars->fDelayOptLut || pPars->fUserLutDec )
     {
         pPars->fTruth      =  1;
         pPars->fCutMin     =  1;
@@ -40983,6 +41014,7 @@ usage:
     Abc_Print( -2, "\t-W float : sets wire delay between adjects LUTs [default = %f]\n", pPars->WireDelay );
     Abc_Print( -2, "\t-S str   : string representing the LUT structure [default = %s]\n", pPars->pLutStruct ? pPars->pLutStruct : "not used" );
     Abc_Print( -2, "\t-J str   : string representing the LUT structure [default = %s]\n", pPars->pLutStruct ? pPars->pLutStruct : "not used" );
+    Abc_Print( -2, "\t-Z num   : the number of LUT inputs for delay-driven LUT decomposition [default = not used]\n" );
     Abc_Print( -2, "\t-q       : toggles preprocessing using several starting points [default = %s]\n", pPars->fPreprocess? "yes": "no" );
     Abc_Print( -2, "\t-a       : toggles area-oriented mapping [default = %s]\n", pPars->fArea? "yes": "no" );
     Abc_Print( -2, "\t-r       : enables expansion/reduction of the best cuts [default = %s]\n", pPars->fExpRed? "yes": "no" );