public static bool Any(ICode ast)
{
var v = new VisitorFindContinuationsRecursive();
v.Visit(ast);
return(v.Continuations.Any());
}
public static IEnumerable <StmtContinuation> Get(ICode ast)
{
var v = new VisitorFindContinuationsRecursive();
v.Visit(ast);
return(v.Continuations);
}
public static ICode V(ICode ast)
{
var ctx = ast.Ctx;
var blockInfo = VisitorSubstituteIrreducable.FindSuitableBlocks.GetInfo(ast);
var bInfo = blockInfo.Select(x => new {
toCount = VisitorContToCounter.GetCount(x.Key, ast),
ast = x.Key,
codeCount = x.Value.numICodes,
}).ToArray();
var block = bInfo.Where(x => x.toCount >= 2).OrderBy(x => x.toCount * x.codeCount).FirstOrDefault();
if (block == null)
{
return(ast);
}
var phis = new Dictionary <Expr, Expr>();
var blockCopies = Enumerable.Range(0, block.toCount - 1)
.Select(x => {
var v = new VisitorDuplicateCode();
var ret = v.Visit(block.ast);
phis = phis.Merge(v.phiMap, (a, b) => new ExprVarPhi(ctx)
{
Exprs = new[] { a, b }
});
return(ret);
})
.Concat(block.ast)
.ToArray();
var contTos = VisitorFindContinuationsRecursive.Get(ast).Where(x => x.To == block.ast).ToArray();
for (int i = 0; i < contTos.Length; i++)
{
var contTo = contTos[i];
var blockCopy = blockCopies[i];
ast = VisitorReplace.V(ast, contTo, blockCopy);
}
ast = VisitorReplaceExprUse.V(ast, phis);
return(ast);
}
public static ICode V(ICode ast)
{
var ctx = ast.Ctx;
var blockInfo = FindSuitableBlocks.GetInfo(ast);
var bestBlock = blockInfo
.Where(x => !x.Value.containsLeaveProtectedRegion && x.Value.numConts <= 1)
.OrderBy(x => x.Value.numConts == 0 ? 1000 : x.Value.numConts)
.ThenBy(x => x.Value.numICodes)
.FirstOrDefault();
if (bestBlock.Key == null)
{
return(ast);
}
if (bestBlock.Value.numConts > 1)
{
// Best block must have just one continuation
return(ast);
}
Stmt addContTo = null;
if (bestBlock.Value.numConts == 0)
{
addContTo = (Stmt)blockInfo.FirstOrDefault(x => x.Value.numConts == 0 && x.Key != bestBlock.Key).Key;
if (addContTo == null)
{
return(ast);
}
}
var blockAst = (Stmt)bestBlock.Key;
if (blockAst.StmtType != Stmt.NodeType.Block)
{
// Best block must be StmtBlock
return(ast);
}
var stmtBlock = (StmtBlock)blockAst;
var stmts = stmtBlock.Statements.ToArray();
var cont = bestBlock.Value.numConts == 0 ? new StmtContinuation(ctx, addContTo, false) : (StmtContinuation)stmts.Last();
var ifSkipContentPhi = new ExprVarPhi(ctx);
var ifSkipInitialVar = ctx.Local(ctx.Boolean);
var ifSkipContentVar = ctx.Local(ctx.Boolean);
var ifSkipContentPhiExprs = new List <Expr> {
ifSkipInitialVar, ifSkipContentVar
};
var ifSkipReset = new StmtAssignment(ctx, ifSkipContentVar, ctx.Literal(false));
var inIfBlock = new StmtBlock(ctx, stmts.Take(stmts.Length - (bestBlock.Value.numConts == 0 ? 0 : 1)));
var ifBlock = new StmtIf(ctx, ctx.ExprGen.Not(ifSkipContentPhi), inIfBlock, null);
var newBlock = new StmtBlock(ctx, ifBlock, ifSkipReset, cont);
ast = VisitorReplace.V(ast, blockAst, newBlock);
var allConts = VisitorFindContinuationsRecursive.Get(ast);
var contsNeedChanging = allConts.Where(x => x != cont && x.To == cont.To).ToArray();
var contsReplaceInfo = contsNeedChanging
.Select(x => {
var ifVar = ctx.Local(ctx.Boolean);
var newCont = new StmtBlock(ctx,
new StmtAssignment(ctx, ifVar, ctx.Literal(true)),
new StmtContinuation(ctx, newBlock, x.LeaveProtectedRegion));
return(new { oldCont = x, ifVar, newCont });
})
.ToArray();
foreach (var contReplace in contsReplaceInfo)
{
ifSkipContentPhiExprs.Add(contReplace.ifVar);
ast = VisitorReplace.V(ast, contReplace.oldCont, contReplace.newCont);
}
ifSkipContentPhi.Exprs = ifSkipContentPhiExprs;
// TODO: Shouldn't be required, but definite-assignment doesn't quite work properly, so is required
var initalSkipVarAssignment = new StmtAssignment(ctx, ifSkipInitialVar, ctx.Literal(false));
var newAst = new StmtBlock(ctx, initalSkipVarAssignment, (Stmt)ast);
return(newAst);
}
public static IEnumerable<StmtContinuation> Get(ICode ast) {
var v = new VisitorFindContinuationsRecursive();
v.Visit(ast);
return v.Continuations;
}
public static bool Any(ICode ast) {
var v = new VisitorFindContinuationsRecursive();
v.Visit(ast);
return v.Continuations.Any();
}