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using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Diagnostics.Contracts;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using VC;
namespace Microsoft.Boogie
{
class DependencyCollector : StandardVisitor
{
private HashSet<DeclWithFormals> dependencies;
public DependencyCollector()
{
dependencies = new HashSet<DeclWithFormals>();
}
public static void Collect(Absy node, out List<DeclWithFormals> dependencies)
{
var dc = new DependencyCollector();
dc.Visit(node);
dependencies = dc.dependencies.ToList();
}
public static string DependenciesChecksum(Implementation impl)
{
List<DeclWithFormals> deps;
DependencyCollector.Collect(impl, out deps);
if (deps.Any(dep => dep.Checksum == null))
{
return null;
}
var md5 = System.Security.Cryptography.MD5.Create();
var data = Encoding.UTF8.GetBytes(deps.MapConcat(dep => dep.Checksum, ""));
var hashedData = md5.ComputeHash(data);
return BitConverter.ToString(hashedData);
}
public override Procedure VisitProcedure(Procedure node)
{
dependencies.Add(node);
return base.VisitProcedure(node);
}
public override Function VisitFunction(Function node)
{
dependencies.Add(node);
return base.VisitFunction(node);
}
public override Cmd VisitCallCmd(CallCmd node)
{
var result = base.VisitCallCmd(node);
var visited = dependencies.Contains(node.Proc);
if (!visited)
{
VisitProcedure(node.Proc);
}
return result;
}
public override Expr VisitNAryExpr(NAryExpr node)
{
var result = base.VisitNAryExpr(node);
var funCall = node.Fun as FunctionCall;
if (funCall != null)
{
var visited = dependencies.Contains(funCall.Func);
if (!visited)
{
VisitFunction(funCall.Func);
if (funCall.Func.DefinitionAxiom != null)
{
VisitAxiom(funCall.Func.DefinitionAxiom);
}
}
}
return result;
}
}
public class VerificationResult
{
public readonly string Checksum;
public readonly string DependeciesChecksum;
public readonly string RequestId;
public readonly ConditionGeneration.Outcome Outcome;
public readonly List<Counterexample> Errors;
public VerificationResult(string requestId, string checksum, string depsChecksum, ConditionGeneration.Outcome outcome, List<Counterexample> errors)
{
Checksum = checksum;
DependeciesChecksum = depsChecksum;
Outcome = outcome;
Errors = errors;
RequestId = requestId;
}
}
public class VerificationResultCache
{
private readonly ConcurrentDictionary<string, VerificationResult> Cache = new ConcurrentDictionary<string, VerificationResult>();
public void Insert(string key, VerificationResult result)
{
Contract.Requires(key != null);
Contract.Requires(result != null);
Cache[key] = result;
}
public VerificationResult Lookup(string key)
{
VerificationResult result;
var success = Cache.TryGetValue(key, out result);
return success ? result : null;
}
public void Clear()
{
Cache.Clear();
}
public void RemoveMatchingKeys(Regex keyRegexp)
{
foreach (var kv in Cache)
{
if (keyRegexp.IsMatch(kv.Key))
{
VerificationResult res;
Cache.TryRemove(kv.Key, out res);
}
}
}
public bool NeedsToBeVerified(Implementation impl, string depsChecksumOfImpl)
{
return 0 < VerificationPriority(impl, depsChecksumOfImpl);
}
public int VerificationPriority(Implementation impl, string depsChecksumOfImpl)
{
if (!Cache.ContainsKey(impl.Id))
{
return 3; // high priority (has been never verified before)
}
else if (Cache[impl.Id].Checksum != impl.Checksum)
{
return 2; // medium priority (old snapshot has been verified before)
}
else if (depsChecksumOfImpl == null || Cache[impl.Id].DependeciesChecksum != depsChecksumOfImpl)
{
return 1; // low priority (the same snapshot has been verified before, but a callee has changed)
}
else
{
return 0; // skip verification
}
}
}
}
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