Version abc80130_2

1 files changed, 349 insertions, 0 deletions

diff --git a/src/opt/ret/retInit.c b/src/opt/ret/retInit.c
new file mode 100644
index 00000000..dcb71c60
--- /dev/null
+++ b/src/opt/ret/retInit.c
@@ -0,0 +1,349 @@
+/**CFile****************************************************************
+
+  FileName    [retInit.c]
+
+  SystemName  [ABC: Logic synthesis and verification system.]
+
+  PackageName [Retiming package.]
+
+  Synopsis    [Initial state computation for backward retiming.]
+
+  Author      [Alan Mishchenko]
+  
+  Affiliation [UC Berkeley]
+
+  Date        [Ver. 1.0. Started - Oct 31, 2006.]
+
+  Revision    [$Id: retInit.c,v 1.00 2006/10/31 00:00:00 alanmi Exp $]
+
+***********************************************************************/
+
+#include "retInt.h"
+
+////////////////////////////////////////////////////////////////////////
+///                        DECLARATIONS                              ///
+////////////////////////////////////////////////////////////////////////
+
+static int Abc_NtkRetimeVerifyModel( Abc_Ntk_t * pNtkCone, Vec_Int_t * vValues, int * pModel );
+
+////////////////////////////////////////////////////////////////////////
+///                     FUNCTION DEFINITIONS                         ///
+////////////////////////////////////////////////////////////////////////
+
+/**Function*************************************************************
+
+  Synopsis    [Computes initial values of the new latches.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+Vec_Int_t * Abc_NtkRetimeInitialValues( Abc_Ntk_t * pNtkCone, Vec_Int_t * vValues, int fVerbose )
+{
+    Vec_Int_t * vSolution;
+    Abc_Ntk_t * pNtkMiter, * pNtkLogic;
+    int RetValue, clk;
+    if ( pNtkCone == NULL )
+        return Vec_IntDup( vValues );
+    // convert the target network to AIG
+    pNtkLogic = Abc_NtkDup( pNtkCone );
+    Abc_NtkToAig( pNtkLogic );
+    // get the miter
+    pNtkMiter = Abc_NtkCreateTarget( pNtkLogic, pNtkLogic->vCos, vValues );
+    if ( fVerbose )
+        printf( "The miter for initial state computation has %d AIG nodes. ", Abc_NtkNodeNum(pNtkMiter) );
+    // solve the miter
+    clk = clock();
+    RetValue = Abc_NtkMiterSat( pNtkMiter, (sint64)500000, (sint64)50000000, 0, NULL, NULL );
+    if ( fVerbose ) 
+        { PRT( "SAT solving time", clock() - clk ); }
+    // analyze the result
+    if ( RetValue == 1 )
+        printf( "Abc_NtkRetimeInitialValues(): The problem is unsatisfiable. DC latch values are used.\n" );
+    else if ( RetValue == -1 )
+        printf( "Abc_NtkRetimeInitialValues(): The SAT problem timed out. DC latch values are used.\n" );
+    else if ( !Abc_NtkRetimeVerifyModel( pNtkCone, vValues, pNtkMiter->pModel ) )
+        printf( "Abc_NtkRetimeInitialValues(): The computed counter-example is incorrect.\n" );
+    // set the values of the latches
+    vSolution = RetValue? NULL : Vec_IntAllocArray( pNtkMiter->pModel, Abc_NtkPiNum(pNtkLogic) );
+    pNtkMiter->pModel = NULL;
+    Abc_NtkDelete( pNtkMiter );
+    Abc_NtkDelete( pNtkLogic );
+    return vSolution;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Computes the results of simulating one node.]
+
+  Description [Assumes that fanins have pCopy set to the input values.]
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Abc_ObjSopSimulate( Abc_Obj_t * pObj )
+{
+    char * pCube, * pSop = pObj->pData;
+    int nVars, Value, v, ResOr, ResAnd, ResVar;
+    assert( pSop && !Abc_SopIsExorType(pSop) );
+    // simulate the SOP of the node
+    ResOr = 0;
+    nVars = Abc_SopGetVarNum(pSop);
+    Abc_SopForEachCube( pSop, nVars, pCube )
+    {
+        ResAnd = 1;
+        Abc_CubeForEachVar( pCube, Value, v )
+        {
+            if ( Value == '0' )
+                ResVar = 1 ^ ((int)Abc_ObjFanin(pObj, v)->pCopy);
+            else if ( Value == '1' )
+                ResVar = (int)Abc_ObjFanin(pObj, v)->pCopy;
+            else
+                continue;
+            ResAnd &= ResVar;
+        }
+        ResOr |= ResAnd;
+    }
+    // complement the result if necessary
+    if ( !Abc_SopGetPhase(pSop) )
+        ResOr ^= 1;
+    return ResOr;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Verifies the counter-example.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Abc_NtkRetimeVerifyModel( Abc_Ntk_t * pNtkCone, Vec_Int_t * vValues, int * pModel )
+{
+    Vec_Ptr_t * vNodes;
+    Abc_Obj_t * pObj;
+    int i, Counter = 0;
+    assert( Abc_NtkIsSopLogic(pNtkCone) );
+    // set the PIs
+    Abc_NtkForEachPi( pNtkCone, pObj, i )
+        pObj->pCopy = (void *)pModel[i];
+    // simulate the internal nodes
+    vNodes = Abc_NtkDfs( pNtkCone, 0 );
+    Vec_PtrForEachEntry( vNodes, pObj, i )
+        pObj->pCopy = (void *)Abc_ObjSopSimulate( pObj );
+    Vec_PtrFree( vNodes );
+    // compare the outputs
+    Abc_NtkForEachPo( pNtkCone, pObj, i )
+        pObj->pCopy = Abc_ObjFanin0(pObj)->pCopy;
+    Abc_NtkForEachPo( pNtkCone, pObj, i )
+        Counter += (Vec_IntEntry(vValues, i) != (int)pObj->pCopy);
+    if ( Counter > 0 )
+        printf( "%d outputs (out of %d) have a value mismatch.\n", Counter, Abc_NtkPoNum(pNtkCone) );
+    return 1;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Transfer latch initial values to pCopy.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Abc_NtkRetimeTranferToCopy( Abc_Ntk_t * pNtk )
+{
+    Abc_Obj_t * pObj;
+    int i;
+    Abc_NtkForEachObj( pNtk, pObj, i )
+        if ( Abc_ObjIsLatch(pObj) )
+            pObj->pCopy = (void *)Abc_LatchIsInit1(pObj);
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Transfer latch initial values from pCopy.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Abc_NtkRetimeTranferFromCopy( Abc_Ntk_t * pNtk )
+{
+    Abc_Obj_t * pObj;
+    int i;
+    Abc_NtkForEachObj( pNtk, pObj, i )
+        if ( Abc_ObjIsLatch(pObj) )
+            pObj->pData = (void *)(pObj->pCopy? ABC_INIT_ONE : ABC_INIT_ZERO);
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Transfer latch initial values to pCopy.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+Vec_Int_t * Abc_NtkRetimeCollectLatchValues( Abc_Ntk_t * pNtk )
+{
+    Vec_Int_t * vValues;
+    Abc_Obj_t * pObj;
+    int i;
+    vValues = Vec_IntAlloc( Abc_NtkLatchNum(pNtk) );
+    Abc_NtkForEachObj( pNtk, pObj, i )
+        if ( Abc_ObjIsLatch(pObj) )
+            Vec_IntPush( vValues, Abc_LatchIsInit1(pObj) );
+    return vValues;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Transfer latch initial values from pCopy.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Abc_NtkRetimeInsertLatchValues( Abc_Ntk_t * pNtk, Vec_Int_t * vValues )
+{
+    Abc_Obj_t * pObj;
+    int i, Counter = 0;
+    Abc_NtkForEachObj( pNtk, pObj, i )
+        if ( Abc_ObjIsLatch(pObj) )
+            pObj->pCopy = (void *)Counter++;
+    Abc_NtkForEachObj( pNtk, pObj, i )
+        if ( Abc_ObjIsLatch(pObj) )
+            pObj->pData = (void *)(vValues? (Vec_IntEntry(vValues,(int)pObj->pCopy)? ABC_INIT_ONE : ABC_INIT_ZERO) : ABC_INIT_DC);
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Transfer latch initial values to pCopy.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+Abc_Ntk_t * Abc_NtkRetimeBackwardInitialStart( Abc_Ntk_t * pNtk )
+{
+    Abc_Ntk_t * pNtkNew;
+    Abc_Obj_t * pObj;
+    int i;
+    // create the network used for the initial state computation
+    pNtkNew = Abc_NtkAlloc( ABC_NTK_LOGIC, ABC_FUNC_SOP, 1 );
+    // create POs corresponding to the initial values
+    Abc_NtkForEachObj( pNtk, pObj, i )
+        if ( Abc_ObjIsLatch(pObj) )
+            pObj->pCopy = Abc_NtkCreatePo(pNtkNew);
+    return pNtkNew;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Transfer latch initial values to pCopy.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Abc_NtkRetimeBackwardInitialFinish( Abc_Ntk_t * pNtk, Abc_Ntk_t * pNtkNew, Vec_Int_t * vValuesOld, int fVerbose )
+{
+    Vec_Int_t * vValuesNew;
+    Abc_Obj_t * pObj;
+    int i;
+    // create PIs corresponding to the initial values
+    Abc_NtkForEachObj( pNtk, pObj, i )
+        if ( Abc_ObjIsLatch(pObj) )
+            Abc_ObjAddFanin( pObj->pCopy, Abc_NtkCreatePi(pNtkNew) );
+    // assign dummy node names
+    Abc_NtkAddDummyPiNames( pNtkNew );
+    Abc_NtkAddDummyPoNames( pNtkNew );
+    // check the network
+    if ( !Abc_NtkCheck( pNtkNew ) )
+        fprintf( stdout, "Abc_NtkRetimeBackwardInitialFinish(): Network check has failed.\n" );
+    // derive new initial values
+    vValuesNew = Abc_NtkRetimeInitialValues( pNtkNew, vValuesOld, fVerbose );
+    // insert new initial values
+    Abc_NtkRetimeInsertLatchValues( pNtk, vValuesNew );
+    if ( vValuesNew ) Vec_IntFree( vValuesNew );
+}
+
+
+/**Function*************************************************************
+
+  Synopsis    [Cycles the circuit to create a new initial state.]
+
+  Description [Simulates the circuit with random input for the given 
+  number of timeframes to get a better initial state.]
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Abc_NtkCycleInitStateSop( Abc_Ntk_t * pNtk, int nFrames, int fVerbose )
+{
+    Vec_Ptr_t * vNodes;
+    Abc_Obj_t * pObj;
+    int i, f;
+    assert( Abc_NtkIsSopLogic(pNtk) );
+    srand( 0x12341234 );
+    // initialize the values
+    Abc_NtkForEachPi( pNtk, pObj, i )
+        pObj->pCopy = (void *)(rand() & 1);
+    Abc_NtkForEachLatch( pNtk, pObj, i )
+        pObj->pCopy = (void *)Abc_LatchIsInit1(pObj);
+    // simulate for the given number of timeframes
+    vNodes = Abc_NtkDfs( pNtk, 0 );
+    for ( f = 0; f < nFrames; f++ )
+    {
+        // simulate internal nodes
+        Vec_PtrForEachEntry( vNodes, pObj, i )
+            pObj->pCopy = (void *)Abc_ObjSopSimulate( pObj );
+        // bring the results to the COs
+        Abc_NtkForEachCo( pNtk, pObj, i )
+            pObj->pCopy = Abc_ObjFanin0(pObj)->pCopy;
+        // assign PI values
+        Abc_NtkForEachPi( pNtk, pObj, i )
+            pObj->pCopy = (void *)(rand() & 1);
+        // transfer the latch values
+        Abc_NtkForEachLatch( pNtk, pObj, i )
+            Abc_ObjFanout0(pObj)->pCopy = Abc_ObjFanin0(pObj)->pCopy;
+    }
+    Vec_PtrFree( vNodes );
+    // set the final values
+    Abc_NtkForEachLatch( pNtk, pObj, i )
+        pObj->pData = (void *)(Abc_ObjFanout0(pObj)->pCopy ? ABC_INIT_ONE : ABC_INIT_ZERO);
+}
+
+////////////////////////////////////////////////////////////////////////
+///                       END OF FILE                                ///
+////////////////////////////////////////////////////////////////////////
+
+