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-rw-r--r--Source/ExecutionEngine/VerificationResultCache.cs1332
1 files changed, 692 insertions, 640 deletions
diff --git a/Source/ExecutionEngine/VerificationResultCache.cs b/Source/ExecutionEngine/VerificationResultCache.cs
index 5d20e6e8..3159238c 100644
--- a/Source/ExecutionEngine/VerificationResultCache.cs
+++ b/Source/ExecutionEngine/VerificationResultCache.cs
@@ -1,640 +1,692 @@
-using System;
-using System.Collections.Concurrent;
-using System.Collections.Generic;
-using System.Diagnostics.Contracts;
-using System.IO;
-using System.Linq;
-using System.Runtime.Caching;
-using System.Text;
-using System.Text.RegularExpressions;
-using VC;
-
-namespace Microsoft.Boogie
-{
-
- struct CachedVerificationResultInjectorRun
- {
- public DateTime Start { get; internal set; }
- public DateTime End { get; internal set; }
- public int TransformedImplementationCount { get; internal set; }
- public int ImplementationCount { get; internal set; }
- public int SkippedImplementationCount { get; set; }
- public int LowPriorityImplementationCount { get; set; }
- public int MediumPriorityImplementationCount { get; set; }
- public int HighPriorityImplementationCount { get; set; }
- public long[] CachingActionCounts { get; set; }
- }
-
-
- sealed class CachedVerificationResultInjectorStatistics
- {
- ConcurrentDictionary<string, CachedVerificationResultInjectorRun> runs = new ConcurrentDictionary<string, CachedVerificationResultInjectorRun>();
-
- public bool AddRun(string requestId, CachedVerificationResultInjectorRun run)
- {
- return runs.TryAdd(requestId, run);
- }
-
- public string Output(bool printTime = false)
- {
- var wr = new StringWriter();
- if (runs.Any())
- {
- wr.WriteLine("Cached verification result injector statistics as CSV:");
- wr.WriteLine("Request ID, Transformed, Low, Medium, High, Skipped{0}", printTime ? ", Time (ms)" : "");
- foreach (var kv in runs.OrderBy(kv => ExecutionEngine.AutoRequestId(kv.Key)))
- {
- var t = printTime ? string.Format(", {0,8:F0}", kv.Value.End.Subtract(kv.Value.Start).TotalMilliseconds) : "";
- wr.WriteLine("{0,-19}, {1,3}, {2,3}, {3,3}, {4,3}, {5,3}{6}", kv.Key, kv.Value.TransformedImplementationCount, kv.Value.LowPriorityImplementationCount, kv.Value.MediumPriorityImplementationCount, kv.Value.HighPriorityImplementationCount, kv.Value.SkippedImplementationCount, t);
- }
- }
- return wr.ToString();
- }
- }
-
-
- sealed class CachedVerificationResultInjector : StandardVisitor
- {
- readonly IEnumerable<Implementation> Implementations;
- readonly Program Program;
- // TODO(wuestholz): We should probably increase the threshold to something like 2 seconds.
- static readonly double TimeThreshold = -1.0d;
- Program programInCachedSnapshot;
- Implementation currentImplementation;
- int assumptionVariableCount;
- int temporaryVariableCount;
-
- public static readonly CachedVerificationResultInjectorStatistics Statistics = new CachedVerificationResultInjectorStatistics();
-
- int FreshAssumptionVariableName
- {
- get
- {
- return assumptionVariableCount++;
- }
- }
-
- int FreshTemporaryVariableName
- {
- get
- {
- return temporaryVariableCount++;
- }
- }
-
- CachedVerificationResultInjector(Program program, IEnumerable<Implementation> implementations)
- {
- Implementations = implementations;
- Program = program;
- }
-
- public Implementation Inject(Implementation implementation, Program programInCachedSnapshot)
- {
- Contract.Requires(implementation != null && programInCachedSnapshot != null);
-
- this.programInCachedSnapshot = programInCachedSnapshot;
- assumptionVariableCount = 0;
- temporaryVariableCount = 0;
- currentImplementation = implementation;
- var result = VisitImplementation(implementation);
- currentImplementation = null;
- this.programInCachedSnapshot = null;
- return result;
- }
-
- public static void Inject(Program program, IEnumerable<Implementation> implementations, string requestId, string programId, out long[] cachingActionCounts)
- {
- var eai = new CachedVerificationResultInjector(program, implementations);
-
- cachingActionCounts = new long[Enum.GetNames(typeof(VC.ConditionGeneration.CachingAction)).Length];
- var run = new CachedVerificationResultInjectorRun { Start = DateTime.UtcNow, ImplementationCount = implementations.Count(), CachingActionCounts = cachingActionCounts };
- foreach (var impl in implementations)
- {
- int priority;
- var vr = ExecutionEngine.Cache.Lookup(impl, out priority);
- if (vr != null && vr.ProgramId == programId)
- {
- if (priority == Priority.LOW)
- {
- run.LowPriorityImplementationCount++;
- if (TimeThreshold < vr.End.Subtract(vr.Start).TotalMilliseconds)
- {
- SetErrorAndAssertionChecksumsInCachedSnapshot(impl, vr);
- if (vr.ProgramId != null)
- {
- var p = ExecutionEngine.CachedProgram(vr.ProgramId);
- if (p != null)
- {
- eai.Inject(impl, p);
- run.TransformedImplementationCount++;
- }
- }
- }
- }
- else if (priority == Priority.MEDIUM)
- {
- run.MediumPriorityImplementationCount++;
- if (TimeThreshold < vr.End.Subtract(vr.Start).TotalMilliseconds)
- {
- SetErrorAndAssertionChecksumsInCachedSnapshot(impl, vr);
- if (vr.ProgramId != null)
- {
- var p = ExecutionEngine.CachedProgram(vr.ProgramId);
- if (p != null)
- {
- eai.Inject(impl, p);
- run.TransformedImplementationCount++;
- }
- }
- }
- }
- else if (priority == Priority.HIGH)
- {
- run.HighPriorityImplementationCount++;
- }
- else if (priority == Priority.SKIP)
- {
- run.SkippedImplementationCount++;
- }
- }
- }
- run.End = DateTime.UtcNow;
- Statistics.AddRun(requestId, run);
- }
-
- private static void SetErrorAndAssertionChecksumsInCachedSnapshot(Implementation implementation, VerificationResult result)
- {
- if (result.Outcome == ConditionGeneration.Outcome.Errors && result.Errors != null && result.Errors.Count < CommandLineOptions.Clo.ProverCCLimit)
- {
- implementation.SetErrorChecksumToCachedError(result.Errors.Select(cex => new Tuple<byte[], byte[], object>(cex.Checksum, cex.SugaredCmdChecksum, cex)));
- implementation.AssertionChecksumsInCachedSnapshot = result.AssertionChecksums;
- }
- else if (result.Outcome == ConditionGeneration.Outcome.Correct)
- {
- implementation.SetErrorChecksumToCachedError(new List<Tuple<byte[], byte[], object>>());
- implementation.AssertionChecksumsInCachedSnapshot = result.AssertionChecksums;
- }
- }
-
- public override Cmd VisitCallCmd(CallCmd node)
- {
- var result = base.VisitCallCmd(node);
-
- var oldProc = programInCachedSnapshot.FindProcedure(node.Proc.Name);
- if (oldProc != null
- && oldProc.DependencyChecksum != node.Proc.DependencyChecksum
- && node.AssignedAssumptionVariable == null)
- {
- var before = new List<Cmd>();
- var beforePrecondtionCheck = new List<Cmd>();
- var after = new List<Cmd>();
- var axioms = new List<Axiom>();
- Expr assumedExpr = new LiteralExpr(Token.NoToken, false);
- // TODO(wuestholz): Try out two alternatives: only do this for low priority implementations or not at all.
- var canUseSpecs = DependencyCollector.CanExpressOldSpecs(oldProc, Program);
- if (canUseSpecs)
- {
- var desugaring = node.Desugaring;
- Contract.Assert(desugaring != null);
- var precond = node.CheckedPrecondition(oldProc, Program, e => FunctionExtractor.Extract(e, Program, axioms));
- if (precond != null)
- {
- var assume = new AssumeCmd(node.tok, precond, new QKeyValue(Token.NoToken, "precondition_previous_snapshot", new List<object>(), null));
- beforePrecondtionCheck.Add(assume);
- }
-
- var unmods = node.UnmodifiedBefore(oldProc);
- var eqs = new List<Expr>();
- foreach (var unmod in unmods)
- {
- var oldUnmod = new LocalVariable(Token.NoToken,
- new TypedIdent(Token.NoToken, string.Format("{0}##old##{1}", unmod.Name, FreshTemporaryVariableName), unmod.Type));
- var lhs = new SimpleAssignLhs(Token.NoToken, new IdentifierExpr(Token.NoToken, oldUnmod));
- var rhs = new IdentifierExpr(Token.NoToken, unmod.Decl);
- before.Add(new AssignCmd(Token.NoToken, new List<AssignLhs> { lhs }, new List<Expr> { rhs }));
- var eq = LiteralExpr.Eq(new IdentifierExpr(Token.NoToken, oldUnmod), new IdentifierExpr(Token.NoToken, unmod.Decl));
- eq.Type = Type.Bool;
- eq.TypeParameters = SimpleTypeParamInstantiation.EMPTY;
- eqs.Add(eq);
- }
-
- var mods = node.ModifiedBefore(oldProc);
- var oldSubst = new Dictionary<Variable, Expr>();
- foreach (var mod in mods)
- {
- var oldMod = new LocalVariable(Token.NoToken,
- new TypedIdent(Token.NoToken, string.Format("{0}##old##{1}", mod.Name, FreshTemporaryVariableName), mod.Type));
- oldSubst[mod.Decl] = new IdentifierExpr(Token.NoToken, oldMod);
- var lhs = new SimpleAssignLhs(Token.NoToken, new IdentifierExpr(Token.NoToken, oldMod));
- var rhs = new IdentifierExpr(Token.NoToken, mod.Decl);
- before.Add(new AssignCmd(Token.NoToken, new List<AssignLhs> { lhs }, new List<Expr> { rhs }));
- }
-
- assumedExpr = node.Postcondition(oldProc, eqs, oldSubst, Program, e => FunctionExtractor.Extract(e, Program, axioms));
- }
-
- if (assumedExpr != null)
- {
- var lv = new LocalVariable(Token.NoToken,
- new TypedIdent(Token.NoToken, string.Format("a##post##{0}", FreshAssumptionVariableName), Type.Bool),
- new QKeyValue(Token.NoToken, "assumption", new List<object>(), null));
- node.AssignedAssumptionVariable = lv;
- currentImplementation.InjectAssumptionVariable(lv, !canUseSpecs);
- var lhs = new SimpleAssignLhs(Token.NoToken, new IdentifierExpr(Token.NoToken, lv));
- var rhs = LiteralExpr.And(new IdentifierExpr(Token.NoToken, lv), assumedExpr);
- var assumed = new AssignCmd(node.tok, new List<AssignLhs> { lhs }, new List<Expr> { rhs });
- after.Add(assumed);
- }
-
- node.ExtendDesugaring(before, beforePrecondtionCheck, after);
- if (CommandLineOptions.Clo.TraceCachingForTesting || CommandLineOptions.Clo.TraceCachingForBenchmarking)
- {
- using (var tokTxtWr = new TokenTextWriter("<console>", Console.Out, false, false))
- {
- var loc = node.tok != null && node.tok != Token.NoToken ? string.Format("{0}({1},{2})", node.tok.filename, node.tok.line, node.tok.col) : "<unknown location>";
- Console.Out.WriteLine("Processing call to procedure {0} in implementation {1} (at {2}):", node.Proc.Name, currentImplementation.Name, loc);
- foreach (var a in axioms)
- {
- Console.Out.Write(" >>> added axiom: ");
- a.Expr.Emit(tokTxtWr);
- Console.Out.WriteLine();
- }
- foreach (var b in before)
- {
- Console.Out.Write(" >>> added before: ");
- b.Emit(tokTxtWr, 0);
- }
- foreach (var b in beforePrecondtionCheck)
- {
- Console.Out.Write(" >>> added before precondition check: ");
- b.Emit(tokTxtWr, 0);
- }
- foreach (var a in after)
- {
- Console.Out.Write(" >>> added after: ");
- a.Emit(tokTxtWr, 0);
- }
- }
- }
- }
-
- return result;
- }
- }
-
-
- sealed class FunctionExtractor : StandardVisitor
- {
- readonly Dictionary<Variable, BoundVariable> Substitutions = new Dictionary<Variable, BoundVariable>();
-
- public override Expr VisitIdentifierExpr(IdentifierExpr node)
- {
- if (node.Decl == null || !(node.Decl is LocalVariable || node.Decl is Formal || node.Decl is GlobalVariable))
- {
- return node;
- }
- else
- {
- BoundVariable boundVar;
- if (!Substitutions.TryGetValue(node.Decl, out boundVar))
- {
- boundVar = new BoundVariable(Token.NoToken, new TypedIdent(Token.NoToken, node.Name, node.Type));
- Substitutions[node.Decl] = boundVar;
- }
- return new IdentifierExpr(node.tok, boundVar);
- }
- }
-
- public static Expr Extract(Expr expr, Program program, List<Axiom> axioms)
- {
- Contract.Requires(expr != null && program != null && !program.TopLevelDeclarationsAreFrozen && axioms != null);
-
- if (expr is LiteralExpr)
- {
- return expr;
- }
-
- var extractor = new FunctionExtractor();
-
- var body = extractor.VisitExpr(expr);
-
- var name = program.FreshExtractedFunctionName();
- var originalVars = extractor.Substitutions.Keys.ToList();
- var formalInArgs = originalVars.Select(v => new Formal(Token.NoToken, new TypedIdent(Token.NoToken, extractor.Substitutions[v].Name, extractor.Substitutions[v].TypedIdent.Type), true)).ToList<Variable>();
- var formalOutArg = new Formal(Token.NoToken, new TypedIdent(Token.NoToken, name + "$result$", expr.Type), false);
- var func = new Function(Token.NoToken, name, formalInArgs, formalOutArg);
- func.AddAttribute("never_pattern");
-
- var boundVars = originalVars.Select(k => extractor.Substitutions[k]);
- var axiomCall = new NAryExpr(Token.NoToken, new FunctionCall(func), boundVars.Select(b => new IdentifierExpr(Token.NoToken, b)).ToList<Expr>());
- axiomCall.Type = expr.Type;
- axiomCall.TypeParameters = SimpleTypeParamInstantiation.EMPTY;
- var eq = LiteralExpr.Eq(axiomCall, body);
- eq.Type = body.Type;
- eq.TypeParameters = SimpleTypeParamInstantiation.EMPTY;
- if (0 < formalInArgs.Count)
- {
- var forallExpr = new ForallExpr(Token.NoToken, boundVars.ToList<Variable>(), new Trigger(Token.NoToken, true, new List<Expr> { axiomCall }), eq);
- body = forallExpr;
- forallExpr.Attributes = new QKeyValue(Token.NoToken, "weight", new List<object> { new LiteralExpr(Token.NoToken, Basetypes.BigNum.FromInt(30)) }, null);
- body.Type = Type.Bool;
- }
- else
- {
- body = eq;
- }
-
- var axiom = new Axiom(Token.NoToken, body);
- func.DefinitionAxiom = axiom;
- program.AddTopLevelDeclaration(func);
- program.AddTopLevelDeclaration(axiom);
- axioms.Add(axiom);
-
- var call = new NAryExpr(Token.NoToken, new FunctionCall(func), originalVars.Select(v => new IdentifierExpr(Token.NoToken, v)).ToList<Expr>());
- call.Type = expr.Type;
- call.TypeParameters = SimpleTypeParamInstantiation.EMPTY;
- return call;
- }
- }
-
-
- sealed class OtherDefinitionAxiomsCollector : ReadOnlyVisitor
- {
- Axiom currentAxiom;
- Trigger currentTrigger;
-
- public static void Collect(IEnumerable<Axiom> axioms)
- {
- var start = DateTime.UtcNow;
-
- var v = new OtherDefinitionAxiomsCollector();
- foreach (var a in axioms)
- {
- v.currentAxiom = a;
- v.VisitExpr(a.Expr);
- v.currentAxiom = null;
- }
-
- var end = DateTime.UtcNow;
- if (CommandLineOptions.Clo.TraceCachingForDebugging)
- {
- Console.Out.WriteLine("Collected other definition axioms within {0:F0} ms.", end.Subtract(start).TotalMilliseconds);
- }
- }
-
- public override QuantifierExpr VisitQuantifierExpr(QuantifierExpr node)
- {
- currentTrigger = node.Triggers;
- while (currentTrigger != null)
- {
- foreach (var e in currentTrigger.Tr)
- {
- VisitExpr(e);
- }
- currentTrigger = currentTrigger.Next;
- }
- return base.VisitQuantifierExpr(node);
- }
-
- public override Expr VisitNAryExpr(NAryExpr node)
- {
- if (currentTrigger != null)
- {
- // We found a function call within a trigger of a quantifier expression.
- var funCall = node.Fun as FunctionCall;
- if (funCall != null && funCall.Func != null && funCall.Func.Checksum != null && funCall.Func.Checksum != "stable")
- {
- funCall.Func.AddOtherDefinitionAxiom(currentAxiom);
- }
- }
- return base.VisitNAryExpr(node);
- }
- }
-
-
- sealed class DependencyCollector : ReadOnlyVisitor
- {
- private DeclWithFormals currentDeclaration;
- private Axiom currentAxiom;
-
- public static void Collect(Program program)
- {
- var start = DateTime.UtcNow;
-
- var dc = new DependencyCollector();
- dc.VisitProgram(program);
-
- var end = DateTime.UtcNow;
- if (CommandLineOptions.Clo.TraceCachingForDebugging)
- {
- Console.Out.WriteLine("Collected dependencies within {0:F0} ms.", end.Subtract(start).TotalMilliseconds);
- }
- }
-
- public static bool CanExpressOldSpecs(Procedure oldProc, Program newProg)
- {
- Contract.Requires(oldProc != null && newProg != null);
-
- var funcs = newProg.Functions;
- var globals = newProg.GlobalVariables;
- return oldProc.DependenciesCollected
- && (oldProc.FunctionDependencies == null || oldProc.FunctionDependencies.All(dep => funcs.Any(f => f.Name == dep.Name && f.DependencyChecksum == dep.DependencyChecksum)))
- && oldProc.Modifies.All(m => globals.Any(g => g.Name == m.Name));
- }
-
- public override Procedure VisitProcedure(Procedure node)
- {
- currentDeclaration = node;
-
- foreach (var param in node.InParams)
- {
- if (param.TypedIdent != null && param.TypedIdent.WhereExpr != null)
- {
- VisitExpr(param.TypedIdent.WhereExpr);
- }
- }
-
- var result = base.VisitProcedure(node);
- node.DependenciesCollected = true;
- currentDeclaration = null;
- return result;
- }
-
- public override Implementation VisitImplementation(Implementation node)
- {
- currentDeclaration = node;
-
- foreach (var param in node.InParams)
- {
- if (param.TypedIdent != null && param.TypedIdent.WhereExpr != null)
- {
- VisitExpr(param.TypedIdent.WhereExpr);
- }
- }
-
- if (node.Proc != null)
- {
- node.AddProcedureDependency(node.Proc);
- }
-
- var result = base.VisitImplementation(node);
- node.DependenciesCollected = true;
- currentDeclaration = null;
- return result;
- }
-
- public override Axiom VisitAxiom(Axiom node)
- {
- if (node.DependenciesCollected)
- {
- if (currentDeclaration != null && node.FunctionDependencies != null)
- {
- foreach (var f in node.FunctionDependencies)
- {
- currentDeclaration.AddFunctionDependency(f);
- }
- }
- return node;
- }
- currentAxiom = node;
- var result = base.VisitAxiom(node);
- node.DependenciesCollected = true;
- currentAxiom = null;
- return result;
- }
-
- public override Function VisitFunction(Function node)
- {
- currentDeclaration = node;
-
- if (node.DefinitionAxiom != null)
- {
- VisitAxiom(node.DefinitionAxiom);
- }
- if (node.OtherDefinitionAxioms != null)
- {
- foreach (var a in node.OtherDefinitionAxioms)
- {
- if (a != node.DefinitionAxiom)
- {
- VisitAxiom(a);
- }
- }
- }
-
- var result = base.VisitFunction(node);
- node.DependenciesCollected = true;
- currentDeclaration = null;
- return result;
- }
-
- public override Cmd VisitCallCmd(CallCmd node)
- {
- if (currentDeclaration != null)
- {
- currentDeclaration.AddProcedureDependency(node.Proc);
- }
-
- return base.VisitCallCmd(node);
- }
-
- public override Expr VisitNAryExpr(NAryExpr node)
- {
- var funCall = node.Fun as FunctionCall;
- if (funCall != null)
- {
- if (currentDeclaration != null)
- {
- currentDeclaration.AddFunctionDependency(funCall.Func);
- }
- if (currentAxiom != null)
- {
- currentAxiom.AddFunctionDependency(funCall.Func);
- }
- }
-
- return base.VisitNAryExpr(node);
- }
- }
-
-
- static internal class Priority
- {
- public static readonly int LOW = 1; // the same snapshot has been verified before, but a callee has changed
- public static readonly int MEDIUM = 2; // old snapshot has been verified before
- public static readonly int HIGH = 3; // has been never verified before
- public static readonly int SKIP = int.MaxValue; // highest priority to get them done as soon as possible
- }
-
-
- public sealed class VerificationResultCache
- {
- private readonly MemoryCache Cache = new MemoryCache("VerificationResultCache");
- private readonly CacheItemPolicy Policy = new CacheItemPolicy { SlidingExpiration = new TimeSpan(0, 10, 0), Priority = CacheItemPriority.Default };
-
-
- public void Insert(Implementation impl, VerificationResult result)
- {
- Contract.Requires(impl != null);
- Contract.Requires(result != null);
-
- Cache.Set(impl.Id, result, Policy);
- }
-
-
- public VerificationResult Lookup(Implementation impl, out int priority)
- {
- Contract.Requires(impl != null);
-
- var result = Cache.Get(impl.Id) as VerificationResult;
- if (result == null)
- {
- priority = Priority.HIGH;
- }
- else if (result.Checksum != impl.Checksum)
- {
- priority = Priority.MEDIUM;
- }
- else if (impl.DependencyChecksum == null || result.DependeciesChecksum != impl.DependencyChecksum)
- {
- priority = Priority.LOW;
- }
- else
- {
- priority = Priority.SKIP;
- }
- return result;
- }
-
-
- public void Clear()
- {
- Cache.Trim(100);
- }
-
-
- public void RemoveMatchingKeys(Regex keyRegexp)
- {
- Contract.Requires(keyRegexp != null);
-
- foreach (var kv in Cache)
- {
- if (keyRegexp.IsMatch(kv.Key))
- {
- Cache.Remove(kv.Key);
- }
- }
- }
-
-
- public int VerificationPriority(Implementation impl)
- {
- Contract.Requires(impl != null);
-
- int priority;
- Lookup(impl, out priority);
- return priority;
- }
- }
-
-}
+using System;
+using System.Collections.Concurrent;
+using System.Collections.Generic;
+using System.Diagnostics.Contracts;
+using System.IO;
+using System.Linq;
+using System.Runtime.Caching;
+using System.Text;
+using System.Text.RegularExpressions;
+using VC;
+
+namespace Microsoft.Boogie
+{
+
+ struct CachedVerificationResultInjectorRun
+ {
+ public DateTime Start { get; internal set; }
+ public DateTime End { get; internal set; }
+ public int TransformedImplementationCount { get; internal set; }
+ public int ImplementationCount { get; internal set; }
+ public int SkippedImplementationCount { get; set; }
+ public int LowPriorityImplementationCount { get; set; }
+ public int MediumPriorityImplementationCount { get; set; }
+ public int HighPriorityImplementationCount { get; set; }
+ public long[] CachingActionCounts { get; set; }
+ }
+
+
+ sealed class CachedVerificationResultInjectorStatistics
+ {
+ ConcurrentDictionary<string, CachedVerificationResultInjectorRun> runs = new ConcurrentDictionary<string, CachedVerificationResultInjectorRun>();
+
+ public bool AddRun(string requestId, CachedVerificationResultInjectorRun run)
+ {
+ return runs.TryAdd(requestId, run);
+ }
+
+ public string Output(bool printTime = false)
+ {
+ var wr = new StringWriter();
+ if (runs.Any())
+ {
+ wr.WriteLine("Cached verification result injector statistics as CSV:");
+ wr.WriteLine("Request ID, Transformed, Low, Medium, High, Skipped{0}", printTime ? ", Time (ms)" : "");
+ foreach (var kv in runs.OrderBy(kv => ExecutionEngine.AutoRequestId(kv.Key)))
+ {
+ var t = printTime ? string.Format(", {0,8:F0}", kv.Value.End.Subtract(kv.Value.Start).TotalMilliseconds) : "";
+ wr.WriteLine("{0,-19}, {1,3}, {2,3}, {3,3}, {4,3}, {5,3}{6}", kv.Key, kv.Value.TransformedImplementationCount, kv.Value.LowPriorityImplementationCount, kv.Value.MediumPriorityImplementationCount, kv.Value.HighPriorityImplementationCount, kv.Value.SkippedImplementationCount, t);
+ }
+ }
+ return wr.ToString();
+ }
+ }
+
+
+ sealed class CachedVerificationResultInjector : StandardVisitor
+ {
+ readonly IEnumerable<Implementation> Implementations;
+ readonly Program Program;
+ // TODO(wuestholz): We should probably increase the threshold to something like 2 seconds.
+ static readonly double TimeThreshold = -1.0d;
+ Program programInCachedSnapshot;
+ Implementation currentImplementation;
+ int assumptionVariableCount;
+ int temporaryVariableCount;
+
+ public static readonly CachedVerificationResultInjectorStatistics Statistics = new CachedVerificationResultInjectorStatistics();
+
+ int FreshAssumptionVariableName
+ {
+ get
+ {
+ return assumptionVariableCount++;
+ }
+ }
+
+ int FreshTemporaryVariableName
+ {
+ get
+ {
+ return temporaryVariableCount++;
+ }
+ }
+
+ CachedVerificationResultInjector(Program program, IEnumerable<Implementation> implementations)
+ {
+ Implementations = implementations;
+ Program = program;
+ }
+
+ public Implementation Inject(Implementation implementation, Program programInCachedSnapshot)
+ {
+ Contract.Requires(implementation != null && programInCachedSnapshot != null);
+
+ this.programInCachedSnapshot = programInCachedSnapshot;
+ assumptionVariableCount = 0;
+ temporaryVariableCount = 0;
+ currentImplementation = implementation;
+
+ #region Introduce explict assumption about the precondition.
+
+ var oldProc = programInCachedSnapshot.FindProcedure(currentImplementation.Proc.Name);
+ if (oldProc != null
+ && oldProc.DependencyChecksum != currentImplementation.Proc.DependencyChecksum
+ && currentImplementation.ExplicitAssumptionAboutCachedPrecondition == null)
+ {
+ var axioms = new List<Axiom>();
+ var after = new List<Cmd>();
+ Expr assumedExpr = new LiteralExpr(Token.NoToken, false);
+ var canUseSpecs = DependencyCollector.CanExpressOldSpecs(oldProc, Program, true);
+ if (canUseSpecs && oldProc.SignatureEquals(currentImplementation.Proc))
+ {
+ var always = Substituter.SubstitutionFromHashtable(currentImplementation.GetImplFormalMap(), true, currentImplementation.Proc);
+ var forOld = Substituter.SubstitutionFromHashtable(new Dictionary<Variable, Expr>());
+ var clauses = oldProc.Requires.Select(r => Substituter.FunctionCallReresolvingApply(always, forOld, r.Condition, Program));
+ var conj = Expr.And(clauses, true);
+ assumedExpr = conj != null ? FunctionExtractor.Extract(conj, Program, axioms) : new LiteralExpr(Token.NoToken, true);
+ }
+
+ if (assumedExpr != null)
+ {
+ var lv = new LocalVariable(Token.NoToken,
+ new TypedIdent(Token.NoToken, string.Format("a##cached##{0}", FreshAssumptionVariableName), Type.Bool),
+ new QKeyValue(Token.NoToken, "assumption", new List<object>(), null));
+ currentImplementation.InjectAssumptionVariable(lv, !canUseSpecs);
+ var lhs = new SimpleAssignLhs(Token.NoToken, new IdentifierExpr(Token.NoToken, lv));
+ var rhs = LiteralExpr.And(new IdentifierExpr(Token.NoToken, lv), assumedExpr);
+ var assumed = new AssignCmd(currentImplementation.tok, new List<AssignLhs> { lhs }, new List<Expr> { rhs });
+ assumed.IrrelevantForChecksumComputation = true;
+ currentImplementation.ExplicitAssumptionAboutCachedPrecondition = assumed;
+ after.Add(assumed);
+ }
+
+ if (CommandLineOptions.Clo.TraceCachingForTesting || CommandLineOptions.Clo.TraceCachingForBenchmarking)
+ {
+ using (var tokTxtWr = new TokenTextWriter("<console>", Console.Out, false, false))
+ {
+ var loc = currentImplementation.tok != null && currentImplementation.tok != Token.NoToken ? string.Format("{0}({1},{2})", currentImplementation.tok.filename, currentImplementation.tok.line, currentImplementation.tok.col) : "<unknown location>";
+ Console.Out.WriteLine("Processing implementation {0} (at {1}):", currentImplementation.Name, loc);
+ foreach (var a in axioms)
+ {
+ Console.Out.Write(" >>> added axiom: ");
+ a.Expr.Emit(tokTxtWr);
+ Console.Out.WriteLine();
+ }
+ foreach (var b in after)
+ {
+ Console.Out.Write(" >>> added after assuming the current precondition: ");
+ b.Emit(tokTxtWr, 0);
+ }
+ }
+ }
+ }
+
+ #endregion
+
+ var result = VisitImplementation(currentImplementation);
+ currentImplementation = null;
+ this.programInCachedSnapshot = null;
+ return result;
+ }
+
+ public static void Inject(Program program, IEnumerable<Implementation> implementations, string requestId, string programId, out long[] cachingActionCounts)
+ {
+ var eai = new CachedVerificationResultInjector(program, implementations);
+
+ cachingActionCounts = new long[Enum.GetNames(typeof(VC.ConditionGeneration.CachingAction)).Length];
+ var run = new CachedVerificationResultInjectorRun { Start = DateTime.UtcNow, ImplementationCount = implementations.Count(), CachingActionCounts = cachingActionCounts };
+ foreach (var impl in implementations)
+ {
+ int priority;
+ var vr = ExecutionEngine.Cache.Lookup(impl, out priority);
+ if (vr != null && vr.ProgramId == programId)
+ {
+ if (priority == Priority.LOW) {
+ run.LowPriorityImplementationCount++;
+ } else if (priority == Priority.MEDIUM) {
+ run.MediumPriorityImplementationCount++;
+ } else if (priority == Priority.HIGH) {
+ run.HighPriorityImplementationCount++;
+ } else if (priority == Priority.SKIP) {
+ run.SkippedImplementationCount++;
+ }
+
+ if (priority == Priority.LOW || priority == Priority.MEDIUM || 3 <= CommandLineOptions.Clo.VerifySnapshots) {
+ if (TimeThreshold < vr.End.Subtract(vr.Start).TotalMilliseconds) {
+ SetErrorAndAssertionChecksumsInCachedSnapshot(impl, vr);
+ if (vr.ProgramId != null) {
+ var p = ExecutionEngine.CachedProgram(vr.ProgramId);
+ if (p != null) {
+ eai.Inject(impl, p);
+ run.TransformedImplementationCount++;
+ }
+ }
+ }
+ }
+ }
+ }
+ run.End = DateTime.UtcNow;
+ Statistics.AddRun(requestId, run);
+ }
+
+ private static void SetErrorAndAssertionChecksumsInCachedSnapshot(Implementation implementation, VerificationResult result)
+ {
+ if (result.Outcome == ConditionGeneration.Outcome.Errors && result.Errors != null && result.Errors.Count < CommandLineOptions.Clo.ProverCCLimit)
+ {
+ implementation.SetErrorChecksumToCachedError(result.Errors.Select(cex => new Tuple<byte[], byte[], object>(cex.Checksum, cex.SugaredCmdChecksum, cex)));
+ implementation.AssertionChecksumsInCachedSnapshot = result.AssertionChecksums;
+ }
+ else if (result.Outcome == ConditionGeneration.Outcome.Correct)
+ {
+ implementation.SetErrorChecksumToCachedError(new List<Tuple<byte[], byte[], object>>());
+ implementation.AssertionChecksumsInCachedSnapshot = result.AssertionChecksums;
+ }
+ }
+
+ public override Cmd VisitCallCmd(CallCmd node)
+ {
+ var result = base.VisitCallCmd(node);
+
+ var oldProc = programInCachedSnapshot.FindProcedure(node.Proc.Name);
+ if (oldProc != null
+ && oldProc.DependencyChecksum != node.Proc.DependencyChecksum
+ && node.AssignedAssumptionVariable == null)
+ {
+ var before = new List<Cmd>();
+ var beforePrecondtionCheck = new List<Cmd>();
+ var after = new List<Cmd>();
+ var axioms = new List<Axiom>();
+ Expr assumedExpr = new LiteralExpr(Token.NoToken, false);
+ // TODO(wuestholz): Try out two alternatives: only do this for low priority implementations or not at all.
+ var canUseSpecs = DependencyCollector.CanExpressOldSpecs(oldProc, Program);
+ if (canUseSpecs && oldProc.SignatureEquals(node.Proc))
+ {
+ var desugaring = node.Desugaring;
+ Contract.Assert(desugaring != null);
+ var precond = node.CheckedPrecondition(oldProc, Program, e => FunctionExtractor.Extract(e, Program, axioms));
+ if (precond != null)
+ {
+ var assume = new AssumeCmd(node.tok, precond, new QKeyValue(Token.NoToken, "precondition_previous_snapshot", new List<object>(), null));
+ assume.IrrelevantForChecksumComputation = true;
+ beforePrecondtionCheck.Add(assume);
+ }
+
+ var unmods = node.UnmodifiedBefore(oldProc);
+ var eqs = new List<Expr>();
+ foreach (var unmod in unmods)
+ {
+ var oldUnmod = new LocalVariable(Token.NoToken,
+ new TypedIdent(Token.NoToken, string.Format("{0}##old##{1}", unmod.Name, FreshTemporaryVariableName), unmod.Type));
+ var lhs = new SimpleAssignLhs(Token.NoToken, new IdentifierExpr(Token.NoToken, oldUnmod));
+ var rhs = new IdentifierExpr(Token.NoToken, unmod.Decl);
+ var cmd = new AssignCmd(Token.NoToken, new List<AssignLhs> { lhs }, new List<Expr> { rhs });
+ cmd.IrrelevantForChecksumComputation = true;
+ before.Add(cmd);
+ var eq = LiteralExpr.Eq(new IdentifierExpr(Token.NoToken, oldUnmod), new IdentifierExpr(Token.NoToken, unmod.Decl));
+ eq.Type = Type.Bool;
+ eq.TypeParameters = SimpleTypeParamInstantiation.EMPTY;
+ eqs.Add(eq);
+ }
+
+ var mods = node.ModifiedBefore(oldProc);
+ var oldSubst = new Dictionary<Variable, Expr>();
+ foreach (var mod in mods)
+ {
+ var oldMod = new LocalVariable(Token.NoToken,
+ new TypedIdent(Token.NoToken, string.Format("{0}##old##{1}", mod.Name, FreshTemporaryVariableName), mod.Type));
+ oldSubst[mod.Decl] = new IdentifierExpr(Token.NoToken, oldMod);
+ var lhs = new SimpleAssignLhs(Token.NoToken, new IdentifierExpr(Token.NoToken, oldMod));
+ var rhs = new IdentifierExpr(Token.NoToken, mod.Decl);
+ var cmd = new AssignCmd(Token.NoToken, new List<AssignLhs> { lhs }, new List<Expr> { rhs });
+ cmd.IrrelevantForChecksumComputation = true;
+ before.Add(cmd);
+ }
+
+ assumedExpr = node.Postcondition(oldProc, eqs, oldSubst, Program, e => FunctionExtractor.Extract(e, Program, axioms));
+ if (assumedExpr == null)
+ {
+ assumedExpr = new LiteralExpr(Token.NoToken, true);
+ }
+ }
+
+ if (assumedExpr != null)
+ {
+ var lv = new LocalVariable(Token.NoToken,
+ new TypedIdent(Token.NoToken, string.Format("a##cached##{0}", FreshAssumptionVariableName), Type.Bool),
+ new QKeyValue(Token.NoToken, "assumption", new List<object>(), null));
+ node.AssignedAssumptionVariable = lv;
+ currentImplementation.InjectAssumptionVariable(lv, !canUseSpecs);
+ var lhs = new SimpleAssignLhs(Token.NoToken, new IdentifierExpr(Token.NoToken, lv));
+ var rhs = LiteralExpr.And(new IdentifierExpr(Token.NoToken, lv), assumedExpr);
+ var assumed = new AssignCmd(node.tok, new List<AssignLhs> { lhs }, new List<Expr> { rhs });
+ assumed.IrrelevantForChecksumComputation = true;
+ after.Add(assumed);
+ }
+
+ node.ExtendDesugaring(before, beforePrecondtionCheck, after);
+ if (CommandLineOptions.Clo.TraceCachingForTesting || CommandLineOptions.Clo.TraceCachingForBenchmarking)
+ {
+ using (var tokTxtWr = new TokenTextWriter("<console>", Console.Out, false, false))
+ {
+ var loc = node.tok != null && node.tok != Token.NoToken ? string.Format("{0}({1},{2})", node.tok.filename, node.tok.line, node.tok.col) : "<unknown location>";
+ Console.Out.WriteLine("Processing call to procedure {0} in implementation {1} (at {2}):", node.Proc.Name, currentImplementation.Name, loc);
+ foreach (var a in axioms)
+ {
+ Console.Out.Write(" >>> added axiom: ");
+ a.Expr.Emit(tokTxtWr);
+ Console.Out.WriteLine();
+ }
+ foreach (var b in before)
+ {
+ Console.Out.Write(" >>> added before: ");
+ b.Emit(tokTxtWr, 0);
+ }
+ foreach (var b in beforePrecondtionCheck)
+ {
+ Console.Out.Write(" >>> added before precondition check: ");
+ b.Emit(tokTxtWr, 0);
+ }
+ foreach (var a in after)
+ {
+ Console.Out.Write(" >>> added after: ");
+ a.Emit(tokTxtWr, 0);
+ }
+ }
+ }
+ }
+
+ return result;
+ }
+ }
+
+
+ sealed class FunctionExtractor : StandardVisitor
+ {
+ readonly Dictionary<Variable, BoundVariable> Substitutions = new Dictionary<Variable, BoundVariable>();
+
+ public override Expr VisitIdentifierExpr(IdentifierExpr node)
+ {
+ if (node.Decl == null || !(node.Decl is LocalVariable || node.Decl is Formal || node.Decl is GlobalVariable))
+ {
+ return node;
+ }
+ else
+ {
+ BoundVariable boundVar;
+ if (!Substitutions.TryGetValue(node.Decl, out boundVar))
+ {
+ boundVar = new BoundVariable(Token.NoToken, new TypedIdent(Token.NoToken, node.Name, node.Type));
+ Substitutions[node.Decl] = boundVar;
+ }
+ return new IdentifierExpr(node.tok, boundVar);
+ }
+ }
+
+ public static Expr Extract(Expr expr, Program program, List<Axiom> axioms)
+ {
+ Contract.Requires(expr != null && program != null && !program.TopLevelDeclarationsAreFrozen && axioms != null);
+
+ if (expr is LiteralExpr)
+ {
+ return expr;
+ }
+
+ var extractor = new FunctionExtractor();
+
+ var body = extractor.VisitExpr(expr);
+
+ var name = program.FreshExtractedFunctionName();
+ var originalVars = extractor.Substitutions.Keys.ToList();
+ var formalInArgs = originalVars.Select(v => new Formal(Token.NoToken, new TypedIdent(Token.NoToken, extractor.Substitutions[v].Name, extractor.Substitutions[v].TypedIdent.Type), true)).ToList<Variable>();
+ var formalOutArg = new Formal(Token.NoToken, new TypedIdent(Token.NoToken, name + "$result$", expr.Type), false);
+ var func = new Function(Token.NoToken, name, formalInArgs, formalOutArg);
+ func.AddAttribute("never_pattern");
+
+ var boundVars = originalVars.Select(k => extractor.Substitutions[k]);
+ var axiomCall = new NAryExpr(Token.NoToken, new FunctionCall(func), boundVars.Select(b => new IdentifierExpr(Token.NoToken, b)).ToList<Expr>());
+ axiomCall.Type = expr.Type;
+ axiomCall.TypeParameters = SimpleTypeParamInstantiation.EMPTY;
+ var eq = LiteralExpr.Eq(axiomCall, body);
+ eq.Type = body.Type;
+ eq.TypeParameters = SimpleTypeParamInstantiation.EMPTY;
+ if (0 < formalInArgs.Count)
+ {
+ var forallExpr = new ForallExpr(Token.NoToken, boundVars.ToList<Variable>(), new Trigger(Token.NoToken, true, new List<Expr> { axiomCall }), eq);
+ body = forallExpr;
+ forallExpr.Attributes = new QKeyValue(Token.NoToken, "weight", new List<object> { new LiteralExpr(Token.NoToken, Basetypes.BigNum.FromInt(30)) }, null);
+ body.Type = Type.Bool;
+ }
+ else
+ {
+ body = eq;
+ }
+
+ var axiom = new Axiom(Token.NoToken, body);
+ func.DefinitionAxiom = axiom;
+ program.AddTopLevelDeclaration(func);
+ program.AddTopLevelDeclaration(axiom);
+ axioms.Add(axiom);
+
+ var call = new NAryExpr(Token.NoToken, new FunctionCall(func), originalVars.Select(v => new IdentifierExpr(Token.NoToken, v)).ToList<Expr>());
+ call.Type = expr.Type;
+ call.TypeParameters = SimpleTypeParamInstantiation.EMPTY;
+ return call;
+ }
+ }
+
+
+ sealed class OtherDefinitionAxiomsCollector : ReadOnlyVisitor
+ {
+ Axiom currentAxiom;
+ Trigger currentTrigger;
+
+ public static void Collect(IEnumerable<Axiom> axioms)
+ {
+ var start = DateTime.UtcNow;
+
+ var v = new OtherDefinitionAxiomsCollector();
+ foreach (var a in axioms)
+ {
+ v.currentAxiom = a;
+ v.VisitExpr(a.Expr);
+ v.currentAxiom = null;
+ }
+
+ var end = DateTime.UtcNow;
+ if (CommandLineOptions.Clo.TraceCachingForDebugging)
+ {
+ Console.Out.WriteLine("Collected other definition axioms within {0:F0} ms.", end.Subtract(start).TotalMilliseconds);
+ }
+ }
+
+ public override QuantifierExpr VisitQuantifierExpr(QuantifierExpr node)
+ {
+ currentTrigger = node.Triggers;
+ while (currentTrigger != null)
+ {
+ foreach (var e in currentTrigger.Tr)
+ {
+ VisitExpr(e);
+ }
+ currentTrigger = currentTrigger.Next;
+ }
+ return base.VisitQuantifierExpr(node);
+ }
+
+ public override Expr VisitNAryExpr(NAryExpr node)
+ {
+ if (currentTrigger != null)
+ {
+ // We found a function call within a trigger of a quantifier expression.
+ var funCall = node.Fun as FunctionCall;
+ if (funCall != null && funCall.Func != null && funCall.Func.Checksum != null && funCall.Func.Checksum != "stable")
+ {
+ funCall.Func.AddOtherDefinitionAxiom(currentAxiom);
+ }
+ }
+ return base.VisitNAryExpr(node);
+ }
+ }
+
+
+ sealed class DependencyCollector : ReadOnlyVisitor
+ {
+ private DeclWithFormals currentDeclaration;
+ private Axiom currentAxiom;
+
+ public static void Collect(Program program)
+ {
+ var start = DateTime.UtcNow;
+
+ var dc = new DependencyCollector();
+ dc.VisitProgram(program);
+
+ var end = DateTime.UtcNow;
+ if (CommandLineOptions.Clo.TraceCachingForDebugging)
+ {
+ Console.Out.WriteLine("Collected dependencies within {0:F0} ms.", end.Subtract(start).TotalMilliseconds);
+ }
+ }
+
+ public static bool CanExpressOldSpecs(Procedure oldProc, Program newProg, bool ignoreModifiesClauses = false)
+ {
+ Contract.Requires(oldProc != null && newProg != null);
+
+ var funcs = newProg.Functions;
+ var globals = newProg.GlobalVariables;
+ return oldProc.DependenciesCollected
+ && (oldProc.FunctionDependencies == null || oldProc.FunctionDependencies.All(dep => funcs.Any(f => f.Name == dep.Name && f.DependencyChecksum == dep.DependencyChecksum)))
+ && (ignoreModifiesClauses || oldProc.Modifies.All(m => globals.Any(g => g.Name == m.Name)));
+ }
+
+ public override Procedure VisitProcedure(Procedure node)
+ {
+ currentDeclaration = node;
+
+ foreach (var param in node.InParams)
+ {
+ if (param.TypedIdent != null && param.TypedIdent.WhereExpr != null)
+ {
+ VisitExpr(param.TypedIdent.WhereExpr);
+ }
+ }
+
+ var result = base.VisitProcedure(node);
+ node.DependenciesCollected = true;
+ currentDeclaration = null;
+ return result;
+ }
+
+ public override Implementation VisitImplementation(Implementation node)
+ {
+ currentDeclaration = node;
+
+ foreach (var param in node.InParams)
+ {
+ if (param.TypedIdent != null && param.TypedIdent.WhereExpr != null)
+ {
+ VisitExpr(param.TypedIdent.WhereExpr);
+ }
+ }
+
+ if (node.Proc != null)
+ {
+ node.AddProcedureDependency(node.Proc);
+ }
+
+ var result = base.VisitImplementation(node);
+ node.DependenciesCollected = true;
+ currentDeclaration = null;
+ return result;
+ }
+
+ public override Axiom VisitAxiom(Axiom node)
+ {
+ if (node.DependenciesCollected)
+ {
+ if (currentDeclaration != null && node.FunctionDependencies != null)
+ {
+ foreach (var f in node.FunctionDependencies)
+ {
+ currentDeclaration.AddFunctionDependency(f);
+ }
+ }
+ return node;
+ }
+ currentAxiom = node;
+ var result = base.VisitAxiom(node);
+ node.DependenciesCollected = true;
+ currentAxiom = null;
+ return result;
+ }
+
+ public override Function VisitFunction(Function node)
+ {
+ currentDeclaration = node;
+
+ if (node.DefinitionAxiom != null)
+ {
+ VisitAxiom(node.DefinitionAxiom);
+ }
+ if (node.OtherDefinitionAxioms != null)
+ {
+ foreach (var a in node.OtherDefinitionAxioms)
+ {
+ if (a != node.DefinitionAxiom)
+ {
+ VisitAxiom(a);
+ }
+ }
+ }
+
+ var result = base.VisitFunction(node);
+ node.DependenciesCollected = true;
+ currentDeclaration = null;
+ return result;
+ }
+
+ public override Cmd VisitCallCmd(CallCmd node)
+ {
+ if (currentDeclaration != null)
+ {
+ currentDeclaration.AddProcedureDependency(node.Proc);
+ }
+
+ return base.VisitCallCmd(node);
+ }
+
+ public override Expr VisitNAryExpr(NAryExpr node)
+ {
+ var funCall = node.Fun as FunctionCall;
+ if (funCall != null)
+ {
+ if (currentDeclaration != null)
+ {
+ currentDeclaration.AddFunctionDependency(funCall.Func);
+ }
+ if (currentAxiom != null)
+ {
+ currentAxiom.AddFunctionDependency(funCall.Func);
+ }
+ }
+
+ return base.VisitNAryExpr(node);
+ }
+ }
+
+
+ static internal class Priority
+ {
+ public static readonly int LOW = 1; // the same snapshot has been verified before, but a callee has changed
+ public static readonly int MEDIUM = 2; // old snapshot has been verified before
+ public static readonly int HIGH = 3; // has been never verified before
+ public static readonly int SKIP = int.MaxValue; // highest priority to get them done as soon as possible
+ }
+
+
+ public sealed class VerificationResultCache
+ {
+ private readonly MemoryCache Cache = new MemoryCache("VerificationResultCache");
+ private readonly CacheItemPolicy Policy = new CacheItemPolicy { SlidingExpiration = new TimeSpan(0, 10, 0), Priority = CacheItemPriority.Default };
+
+
+ public void Insert(Implementation impl, VerificationResult result)
+ {
+ Contract.Requires(impl != null);
+ Contract.Requires(result != null);
+
+ Cache.Set(impl.Id, result, Policy);
+ }
+
+
+ public VerificationResult Lookup(Implementation impl, out int priority)
+ {
+ Contract.Requires(impl != null);
+
+ var result = Cache.Get(impl.Id) as VerificationResult;
+ if (result == null)
+ {
+ priority = Priority.HIGH;
+ }
+ else if (result.Checksum != impl.Checksum)
+ {
+ priority = Priority.MEDIUM;
+ }
+ else if (impl.DependencyChecksum == null || result.DependeciesChecksum != impl.DependencyChecksum)
+ {
+ priority = Priority.LOW;
+ }
+ else if (result.Outcome == ConditionGeneration.Outcome.TimedOut && CommandLineOptions.Clo.RunDiagnosticsOnTimeout)
+ {
+ priority = Priority.MEDIUM;
+ }
+ else
+ {
+ priority = Priority.SKIP;
+ }
+ return result;
+ }
+
+
+ public void Clear()
+ {
+ Cache.Trim(100);
+ }
+
+
+ public void RemoveMatchingKeys(Regex keyRegexp)
+ {
+ Contract.Requires(keyRegexp != null);
+
+ foreach (var kv in Cache)
+ {
+ if (keyRegexp.IsMatch(kv.Key))
+ {
+ Cache.Remove(kv.Key);
+ }
+ }
+ }
+
+
+ public int VerificationPriority(Implementation impl)
+ {
+ Contract.Requires(impl != null);
+
+ int priority;
+ Lookup(impl, out priority);
+ return priority;
+ }
+ }
+
+}