private void CreateOrMergeBsi(Stmt s, Expr[] stack, Expr[] locals, Expr[] args) {
if (s.StmtType == Stmt.NodeType.Try) {
var sTry = (StmtTry)s;
// It is fine to use 'locals' and 'args' in catch/finally because the phi clustering performed later
// will conglomerate all the necessary variables
if (sTry.Catches != null) {
var catch0 = sTry.Catches.First();
this.CreateOrMergeBsi(catch0.Stmt, new Expr[] { catch0.ExceptionVar }, locals, args);
}
if (sTry.Finally != null) {
this.CreateOrMergeBsi(sTry.Finally, new Expr[0], locals, args);
}
this.CreateOrMergeBsi(sTry.Try, stack, locals, args);
return;
}
if (s.StmtType != Stmt.NodeType.Cil) {
throw new InvalidCastException("Should not be seeing: " + s.StmtType);
}
// Perform create/merge
Func<Expr, IEnumerable<Expr>> flattenPhiExprs = null;
flattenPhiExprs = e => {
if (e.ExprType == Expr.NodeType.VarPhi) {
return ((ExprVarPhi)e).Exprs.SelectMany(x => flattenPhiExprs(x));
}
return new[] { e };
};
Action<ExprVarPhi[], IEnumerable<Expr>> merge = (bsiVars, thisVars) => {
foreach (var v in bsiVars.Zip(thisVars, (a, b) => new { phi = a, add = b })) {
if (v.add != null) {
v.phi.Exprs = flattenPhiExprs(v.add).Concat(v.phi.Exprs).Where(x => x != null && x != v.phi).Distinct().ToArray();
}
}
};
BlockInitInfo bsi;
if (!this.blockStartInfos.TryGetValue(s, out bsi)) {
Func<IEnumerable<Expr>, ExprVarPhi[]> create = exprs => exprs.Select(x => {
if (x == null) {
return new ExprVarPhi(this.ctx) { Exprs = new Expr[0] };
}
if (x.ExprType == Expr.NodeType.VarPhi) {
return (ExprVarPhi)x;
}
return new ExprVarPhi(this.ctx) { Exprs = new[] { x } };
}).ToArray();
bsi = new BlockInitInfo {
Stack = create(stack),
Locals = create(locals),
Args = create(args),
};
this.blockStartInfos.Add(s, bsi);
} else {
merge(bsi.Stack, stack);
merge(bsi.Locals, locals);
merge(bsi.Args, args);
// Forward-merge through already-processed nodes for vars that are not changed in a node
var fmSeen = new HashSet<Stmt>();
Action<Stmt> forwardMerge = null;
forwardMerge = (stmt) => {
if (fmSeen.Add(stmt)) {
var fmBsi = this.blockStartInfos.ValueOrDefault(stmt);
var fmChanges = this.stmtVarsChanged.ValueOrDefault(stmt);
if (fmBsi != null && fmChanges != null) {
var fmStack = fmBsi.Stack.Take(fmChanges.Stack.Length).Select((x, i) => fmChanges.Stack[i] ? x : null).ToArray();
var fmLocals = fmBsi.Locals.Take(fmChanges.Locals.Length).Select((x, i) => fmChanges.Locals[i] ? x : null).ToArray();
var fmArgs = fmBsi.Args.Take(fmChanges.Args.Length).Select((x, i) => fmChanges.Args[i] ? x : null).ToArray();
if (fmStack.Any(x => x != null) || fmLocals.Any(x => x != null) || fmArgs.Any(x => x != null)) {
var fmConts = VisitorFindContinuations.Get(stmt);
foreach (var fmCont in fmConts) {
var fmContBsi = this.blockStartInfos.ValueOrDefault(fmCont.To);
if (fmContBsi != null) {
merge(fmContBsi.Stack, fmStack);
merge(fmContBsi.Locals, fmLocals);
merge(fmContBsi.Args, fmArgs);
forwardMerge(fmCont.To);
}
}
}
}
}
};
forwardMerge(s);
}
}
private void CreateOrMergeBsi(Stmt s, Expr[] stack, Expr[] locals, Expr[] args)
{
if (s.StmtType == Stmt.NodeType.Try)
{
var sTry = (StmtTry)s;
// It is fine to use 'locals' and 'args' in catch/finally because the phi clustering performed later
// will conglomerate all the necessary variables
if (sTry.Catches != null)
{
var catch0 = sTry.Catches.First();
this.CreateOrMergeBsi(catch0.Stmt, new Expr[] { catch0.ExceptionVar }, locals, args);
}
if (sTry.Finally != null)
{
this.CreateOrMergeBsi(sTry.Finally, new Expr[0], locals, args);
}
this.CreateOrMergeBsi(sTry.Try, stack, locals, args);
return;
}
if (s.StmtType != Stmt.NodeType.Cil)
{
throw new InvalidCastException("Should not be seeing: " + s.StmtType);
}
// Perform create/merge
Func <Expr, IEnumerable <Expr> > flattenPhiExprs = null;
flattenPhiExprs = e => {
if (e.ExprType == Expr.NodeType.VarPhi)
{
return(((ExprVarPhi)e).Exprs.SelectMany(x => flattenPhiExprs(x)));
}
return(new[] { e });
};
Action <ExprVarPhi[], IEnumerable <Expr> > merge = (bsiVars, thisVars) => {
foreach (var v in bsiVars.Zip(thisVars, (a, b) => new { phi = a, add = b }))
{
if (v.add != null)
{
v.phi.Exprs = flattenPhiExprs(v.add).Concat(v.phi.Exprs).Where(x => x != null && x != v.phi).Distinct().ToArray();
}
}
};
BlockInitInfo bsi;
if (!this.blockStartInfos.TryGetValue(s, out bsi))
{
Func <IEnumerable <Expr>, ExprVarPhi[]> create = exprs => exprs.Select(x => {
if (x == null)
{
return(new ExprVarPhi(this.ctx)
{
Exprs = new Expr[0]
});
}
if (x.ExprType == Expr.NodeType.VarPhi)
{
return((ExprVarPhi)x);
}
return(new ExprVarPhi(this.ctx)
{
Exprs = new[] { x }
});
}).ToArray();
bsi = new BlockInitInfo {
Stack = create(stack),
Locals = create(locals),
Args = create(args),
};
this.blockStartInfos.Add(s, bsi);
}
else
{
merge(bsi.Stack, stack);
merge(bsi.Locals, locals);
merge(bsi.Args, args);
// Forward-merge through already-processed nodes for vars that are not changed in a node
var fmSeen = new HashSet <Stmt>();
Action <Stmt> forwardMerge = null;
forwardMerge = (stmt) => {
if (fmSeen.Add(stmt))
{
var fmBsi = this.blockStartInfos.ValueOrDefault(stmt);
var fmChanges = this.stmtVarsChanged.ValueOrDefault(stmt);
if (fmBsi != null && fmChanges != null)
{
var fmStack = fmBsi.Stack.Take(fmChanges.Stack.Length).Select((x, i) => fmChanges.Stack[i] ? x : null).ToArray();
var fmLocals = fmBsi.Locals.Take(fmChanges.Locals.Length).Select((x, i) => fmChanges.Locals[i] ? x : null).ToArray();
var fmArgs = fmBsi.Args.Take(fmChanges.Args.Length).Select((x, i) => fmChanges.Args[i] ? x : null).ToArray();
if (fmStack.Any(x => x != null) || fmLocals.Any(x => x != null) || fmArgs.Any(x => x != null))
{
var fmConts = VisitorFindContinuations.Get(stmt);
foreach (var fmCont in fmConts)
{
var fmContBsi = this.blockStartInfos.ValueOrDefault(fmCont.To);
if (fmContBsi != null)
{
merge(fmContBsi.Stack, fmStack);
merge(fmContBsi.Locals, fmLocals);
merge(fmContBsi.Args, fmArgs);
forwardMerge(fmCont.To);
}
}
}
}
}
};
forwardMerge(s);
}
}