//ITE FUNCTION
int circuit::ITE(int i, int t, int e){
int terminalResult = 0;
//Check if ITE is a terminal node
if(terminal(i, t, e, terminalResult)){
return terminalResult;
}
//Check computed Table to see if ITE is already computed
if(iteExists(i,t,e, terminalResult))
return terminalResult;
//Get top variable give i t e
int top = topVariable(i, t, e);
//Recurse ITE through true and false edge
int TE = ITE(function(i, top, true), function(t, top, true), function(e, top, true));
int FE = ITE(function(i, top, false), function(t, top, false), function(e, top, false));
//Check if TE and FE are the same.
if(TE == FE)
return TE;
//Add node into table if unique
int label = insertUT(top, TE, FE);
//Add node to CT;
int keys[] = {i, t, e};
std::vector<int> key (keys, keys+sizeof(keys)/sizeof(int));
hashCT[key] = label;
return label;
}
static
//Formula buildBDD(const Linear& c, int size, int lower_limit, int upper_limit, int material_left, Map<Pair<int,Int>,Formula>& memo, int max_cost)
Formula buildBDD(const Linear& c, int size, Int sum, Int material_left, Map<Pair<int,Int>,Formula>& memo, int max_cost)
{
Int lower_limit = (c.lo == Int_MIN) ? Int_MIN : c.lo - sum;
Int upper_limit = (c.hi == Int_MAX) ? Int_MAX : c.hi - sum;
if (lower_limit <= 0 && upper_limit >= material_left)
return _1_;
else if (lower_limit > material_left || upper_limit < 0)
return _0_;
else if (FEnv::topSize() > max_cost)
return _undef_; // (mycket elegant!)
Pair<int,Int> key = Pair_new(size, lower_limit);
Formula ret;
if (!memo.peek(key, ret)){
assert(size != 0);
size--;
material_left -= c(size);
Int hi_sum = sign(c[size]) ? sum : sum + c(size);
Int lo_sum = sign(c[size]) ? sum + c(size) : sum;
Formula hi = buildBDD(c, size, hi_sum, material_left, memo, max_cost);
if (hi == _undef_) return _undef_;
Formula lo = buildBDD(c, size, lo_sum, material_left, memo, max_cost);
if (lo == _undef_) return _undef_;
ret = ITE(var(var(c[size])), hi, lo);
memo.set(key, ret);
}
return ret;
}
//Extracts BDD From circuit file
void circuit::getBDD(){
//Cycle through every gate (Gate is ordered in level fashion)
for(int i = numInputs+1; i < numgates; i++){
int gate = gtype[i]; // Get the gate type
int index = 0;
int f,g,h;
int *in = faninlist[i]; // Get the fanin list for the gate
//Check which gate we are dealing with and call ITE
switch(gate){
case 3: //XOR
index = ITE(gateNode[in[0]], -1 * gateNode[in[1]], gateNode[in[1]]);
break;
case 4: //XNOR
index = ITE(gateNode[in[0]], gateNode[in[1]], -1 * gateNode[in[1]]);
break;
case 6: //AND
index = ITE(gateNode[in[0]], gateNode[in[1]], 1);
//Check for multi input
for(int j = 2; j < (fanin[i]); j++)
index = ITE(gateNode[in[j]], index, 1);
break;
case 7: //NAND
//Check for multi input. If more and 2 input, gates are and gates with the last one being a nand gate
if(fanin[i] < 3)
index = ITE(gateNode[in[0]], -1 * (gateNode[in[1]]), 2);
else{
index = ITE(gateNode[in[0]], gateNode[in[1]], 1);
for(int j = 2; j < (fanin[i] - 1); j++)
index = ITE(index, gateNode[in[j]], 1);
index = ITE(index, -1 * gateNode[in[fanin[i]-1]], 2);
}
break;
case 8: //OR
index = ITE(gateNode[in[0]], 2, gateNode[in[1]]);
for(int j = 2; j < (fanin[i]); j++)
index = ITE(gateNode[in[j]], 2, index);
break;
case 9: //NOR
//Check for multi input. If more and 2 input, gates are and gates with the last one being a nor gate
if(fanin[i] < 3)
index = ITE(gateNode[in[0]], 1, -1 * (gateNode[in[1]]));
else{
index = ITE(gateNode[in[0]], 2, gateNode[in[1]]);
for(int j = 2; j < (fanin[i] - 1); j++)
index = ITE(gateNode[in[j]], 2, index);
index = ITE(index, 1, -1 * gateNode[in[fanin[i]-1]]);
}
break;
case 10: //NOT
index = ITE(gateNode[in[0]], 1, 2);
break;
};
//Add BDD node for that gate number
gateNode.push_back(index);
}
}
* * * Copyright 1988 Regents of the University of California * Permission to use, copy, modify, and distribute this * software and its documentation for any purpose and without * fee is hereby granted, provided that the above copyright * notice appear in all copies. The University of California * makes no representations about the suitability of this * software for any purpose. It is provided "as is" without * express or implied warranty. * */ #ifndef lint static char rcsid[] = "$Header$ SPR ITE (Berkeley)"; #endif not lint #define GOOD_SYSLOG #include "sprite.h" #include "mach.h" #include "proc.h" #include "vmMachInt.h" #include "vm.h" #include "vmInt.h" #include "machMon.h" #include "net.h" #include "netEther.h" #include "netInet.h" #include "dev.h"
