// Partially evaluate the programList with respect to the given static inputs,
// producing a new ProgramLines object.
public ProgramLines PEval(Value[] args, FullCellAddr[] residualInputs)
{
PEnv pEnv = new PEnv();
// Map static input cells to their constant values:
for (int i = 0; i < args.Length; i++)
{
pEnv[inputCells[i]] = CGConst.Make(args[i]);
}
ProgramLines residual = new ProgramLines(outputCell, residualInputs);
// PE-time environment PEnv maps each residual input cell address to the delegate argument:
for (int i = 0; i < residualInputs.Length; i++)
{
FullCellAddr input = residualInputs[i];
pEnv[input] = new CGCellRef(input, residual.addressToVariable[input]);
}
// Process the given function's compute cells in dependency order, output last:
foreach (ComputeCell ccell in programList)
{
ComputeCell rCcell = ccell.PEval(pEnv);
if (rCcell != null)
{
residual.AddComputeCell(ccell.cellAddr, rCcell);
}
}
residual = residual.PruneZeroUseCells();
return(residual);
}
public void AddComputeCell(FullCellAddr fca, ComputeCell ccell)
{
programList.Add(ccell);
fcaToComputeCell.Add(fca, ccell);
if (ccell.var != null)
{
addressToVariable.Add(fca, ccell.var);
}
}
// Returns residual ComputeCell or null if no cell needed
public ComputeCell PEval(PEnv pEnv)
{
CGExpr rCond = null;
if (evalCond != null) // Never the case for an output cell
{
rCond = evalCond.PEval(pEnv, false /* not dynamic control */);
}
if (rCond is CGNumberConst)
{
if ((rCond as CGNumberConst).number.value != 0.0)
{
rCond = null; // eval cond constant TRUE, discard eval cond
}
else
{
return(null); // eval cond constant FALSE, discard entire compute cell
}
}
// If residual eval cond is not TRUE then expr has dynamic control
CGExpr rExpr = expr.PEval(pEnv, rCond != null);
if (rExpr is CGConst && var != null)
{
// If cell's value is constant and it is not an output cell just put in PEnv
pEnv[cellAddr] = rExpr;
return(null);
}
else
{
// Else create fresh local variable for the residual cell, and make
// PEnv map cell address to that local variable:
Variable newVar = var != null?var.Fresh() : null;
pEnv[cellAddr] = new CGCellRef(cellAddr, newVar);
ComputeCell result = new ComputeCell(rExpr, newVar, cellAddr);
// result.EvalCond = rCond; // Don't save residual eval cond, we compute it accurately later...
return(result);
}
}
public void ComputeEvalConds()
{
const int THRESHOLD = 30;
// Compute evaluation condition for each cell
IDictionary <FullCellAddr, PathCond> evalConds = new Dictionary <FullCellAddr, PathCond>();
evalConds[outputCell] = PathCond.TRUE;
// The outputCell is also the first ccell processed below
for (int i = programList.Count - 1; i >= 0; i--)
{
ComputeCell ccell = programList[i];
int bound = THRESHOLD;
bool isSerious = ccell.expr.IsSerious(ref bound);
PathCond evalCond = evalConds[ccell.cellAddr];
// Console.WriteLine("evalConds[{0}{1}] = {2}\n", casv.cellAddr, isSerious ? "" : ":TRIVIAL", evalCond);
if (isSerious && !evalCond.Is(true))
{
Console.WriteLine("Setting EvalCond[{0}] = {1}", ccell.cellAddr, evalCond);
ccell.EvalCond = evalCond.ToCGExpr();
}
ccell.expr.EvalCond(evalCond, evalConds, caches);
}
}
// Returns residual ComputeCell or null if no cell needed
public ComputeCell PEval(PEnv pEnv) {
CGExpr rCond = null;
if (evalCond != null) // Never the case for an output cell
{
rCond = evalCond.PEval(pEnv, false /* not dynamic control */);
}
if (rCond is CGNumberConst) {
if ((rCond as CGNumberConst).number.value != 0.0) {
rCond = null; // eval cond constant TRUE, discard eval cond
}
else {
return null; // eval cond constant FALSE, discard entire compute cell
}
}
// If residual eval cond is not TRUE then expr has dynamic control
CGExpr rExpr = expr.PEval(pEnv, rCond != null);
if (rExpr is CGConst && var != null) {
// If cell's value is constant and it is not an output cell just put in PEnv
pEnv[cellAddr] = rExpr;
return null;
}
else {
// Else create fresh local variable for the residual cell, and make
// PEnv map cell address to that local variable:
Variable newVar = var != null ? var.Fresh() : null;
pEnv[cellAddr] = new CGCellRef(cellAddr, newVar);
ComputeCell result = new ComputeCell(rExpr, newVar, cellAddr);
// result.EvalCond = rCond; // Don't save residual eval cond, we compute it accurately later...
return result;
}
}
public void AddComputeCell(FullCellAddr fca, ComputeCell ccell) {
programList.Add(ccell);
fcaToComputeCell.Add(fca, ccell);
if (ccell.var != null) {
addressToVariable.Add(fca, ccell.var);
}
}
