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Speed up dafny verify by reducing memory pressure #5827

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cddc25e
Some steps towards freeing memory after verifying a module
keyboardDrummer Oct 11, 2024
d4c5a8c
Remove a register call
keyboardDrummer Oct 11, 2024
991ff2e
Boogie submodule
keyboardDrummer Oct 11, 2024
582d16f
Use empty verification cache when possible
keyboardDrummer Oct 11, 2024
87096ef
Newer boogie
keyboardDrummer Oct 11, 2024
abc628c
Add release notes
keyboardDrummer Oct 11, 2024
c64a112
Remove old logging
keyboardDrummer Oct 11, 2024
4cb6f4a
Update --progress option
keyboardDrummer Oct 12, 2024
629b2f9
Remove Boogie submodule
keyboardDrummer Oct 12, 2024
23b83ca
Update Boogie to newer version
keyboardDrummer Oct 12, 2024
8a7e1c5
Merge branch 'master' into onlyClaimVerificationMemoryPerModule
keyboardDrummer Oct 12, 2024
69e3d94
Fix compilation issues
keyboardDrummer Oct 15, 2024
2915dd4
Merge branch 'onlyClaimVerificationMemoryPerModule' of github.com:key…
keyboardDrummer Oct 15, 2024
7f9ca76
Merge branch 'master' into onlyClaimVerificationMemoryPerModule
keyboardDrummer Oct 15, 2024
63c93de
Fix tests and an ordering bug
keyboardDrummer Oct 15, 2024
0f48550
Fix expect files
keyboardDrummer Oct 16, 2024
e65de8d
Update customBoogie
keyboardDrummer Oct 16, 2024
896f87b
Merge branch 'master' into onlyClaimVerificationMemoryPerModule
keyboardDrummer Oct 16, 2024
e65e374
Remove comment
keyboardDrummer Oct 16, 2024
a0ab5c1
Merge branch 'onlyClaimVerificationMemoryPerModule' of github.com:key…
keyboardDrummer Oct 16, 2024
0e95710
Merge branch 'master' into onlyClaimVerificationMemoryPerModule
keyboardDrummer Oct 17, 2024
8419a62
Merge branch 'master' into onlyClaimVerificationMemoryPerModule
keyboardDrummer Oct 17, 2024
b823a08
Update documentation
keyboardDrummer Oct 18, 2024
6ae6071
Merge remote-tracking branch 'origin/master' into onlyClaimVerificati…
keyboardDrummer Oct 21, 2024
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4 changes: 4 additions & 0 deletions Source/DafnyCore/Generic/LazyConcurrentDictionary.cs
Original file line number Diff line number Diff line change
Expand Up @@ -62,4 +62,8 @@ public bool TryGetValue(TKey key, out TValue? value) {
}

public TValue this[TKey key] => underlyingDictionary[key].Value;

public bool Remove(TKey key) {
return underlyingDictionary.TryRemove(key, out _);
}
}
10 changes: 6 additions & 4 deletions Source/DafnyCore/Options/CommonOptionBag.cs
Original file line number Diff line number Diff line change
Expand Up @@ -14,10 +14,12 @@ public class CommonOptionBag {

public static void EnsureStaticConstructorHasRun() { }

public static readonly Option<bool> ProgressOption =
new("--progress", "While verifying, output information that helps track progress") {
IsHidden = true
};
public enum ProgressLevel { None, Symbol, VerificationJobs }
public static readonly Option<ProgressLevel> ProgressOption =
new("--progress", $"While verifying, output information that helps track progress. " +
$"Use '{ProgressLevel.Symbol}' to show progress across symbols such as methods and functions. " +
$"Verification of a symbol is usually split across several jobs. " +
$"Use {ProgressLevel.VerificationJobs} to additionally show progress across jobs.");

public static readonly Option<string> LogLocation =
new("--log-location", "Sets the directory where to store log files") {
Expand Down
18 changes: 14 additions & 4 deletions Source/DafnyCore/Pipeline/Compilation.cs
Original file line number Diff line number Diff line change
Expand Up @@ -332,9 +332,6 @@ private async Task VerifyUnverifiedSymbol(bool onlyPrepareVerificationForGutterT
tasksForModule = await translatedModules.GetOrAdd(containingModule, async () => {
var result = await verifier.GetVerificationTasksAsync(boogieEngine, resolution, containingModule,
cancellationSource.Token);
foreach (var task in result) {
cancellationSource.Token.Register(task.Cancel);
}

return result.GroupBy(t => ((IToken)t.ScopeToken).GetFilePosition()).ToDictionary(
g => g.Key,
Expand Down Expand Up @@ -433,6 +430,11 @@ private void HandleStatusUpdate(ICanVerify canVerify, IVerificationTask verifica

public void CancelPendingUpdates() {
cancellationSource.Cancel();
foreach (var (_, tasks) in tasksPerVerifiable) {
foreach (var task in tasks) {
task.Cancel();
}
}
}

public async Task<TextEditContainer?> GetTextEditToFormatCode(Uri uri) {
Expand Down Expand Up @@ -507,7 +509,7 @@ public static void ReportDiagnosticsInResult(DafnyOptions options, string name,

// This reports problems that are not captured by counter-examples, like a time-out
// The Boogie API forces us to create a temporary engine here to report the outcome, even though it only uses the options.
var boogieEngine = new ExecutionEngine(options, new VerificationResultCache(),
var boogieEngine = new ExecutionEngine(options, new EmptyVerificationResultCache(),
CustomStackSizePoolTaskScheduler.Create(0, 0));
boogieEngine.ReportOutcome(null, outcome, outcomeError => errorReporter.ReportBoogieError(outcomeError, null, false),
name, token, null, TextWriter.Null,
Expand Down Expand Up @@ -579,4 +581,12 @@ public static VcOutcome GetOutcome(SolverOutcome outcome) {
throw new ArgumentOutOfRangeException(nameof(outcome), outcome, null);
}
}

public void ClearModuleCache(ModuleDefinition moduleDefinition) {
translatedModules.Remove(moduleDefinition);
}

public void ClearCanVerifyCache(ICanVerify canVerify) {
tasksPerVerifiable.Remove(canVerify);
}
}
2 changes: 1 addition & 1 deletion Source/DafnyDriver/CliCanVerifyState.cs
Original file line number Diff line number Diff line change
Expand Up @@ -10,5 +10,5 @@ public record CliCanVerifyState {
public Func<IVerificationTask, bool> TaskFilter = _ => true;
public readonly TaskCompletionSource Finished = new();
public readonly ConcurrentQueue<(IVerificationTask Task, Completed Result)> CompletedParts = new();
public readonly ConcurrentBag<IVerificationTask> Tasks = new();
public int TaskCount;
}
85 changes: 48 additions & 37 deletions Source/DafnyDriver/CliCompilation.cs
Original file line number Diff line number Diff line change
Expand Up @@ -45,7 +45,7 @@ private CliCompilation(
options.RunningBoogieFromCommandLine = true;

var input = new CompilationInput(options, 0, options.DafnyProject);
var executionEngine = new ExecutionEngine(options, new VerificationResultCache(), DafnyMain.LargeThreadScheduler);
var executionEngine = new ExecutionEngine(options, new EmptyVerificationResultCache(), DafnyMain.LargeThreadScheduler);
Compilation = createCompilation(executionEngine, input);
}

Expand Down Expand Up @@ -162,10 +162,10 @@ public async IAsyncEnumerable<CanVerifyResult> VerifyAllLazily(int? randomSeed)
if (ev is CanVerifyPartsIdentified canVerifyPartsIdentified) {
var canVerifyResult = canVerifyResults[canVerifyPartsIdentified.CanVerify];
foreach (var part in canVerifyPartsIdentified.Parts.Where(canVerifyResult.TaskFilter)) {
canVerifyResult.Tasks.Add(part);
Interlocked.Increment(ref canVerifyResult.TaskCount);
}

if (canVerifyResult.CompletedParts.Count == canVerifyResult.Tasks.Count) {
if (canVerifyResult.CompletedParts.Count == canVerifyResult.TaskCount) {
canVerifyResult.Finished.SetResult();
}
}
Expand All @@ -184,17 +184,17 @@ public async IAsyncEnumerable<CanVerifyResult> VerifyAllLazily(int? randomSeed)
var canVerifyResult = canVerifyResults[boogieUpdate.CanVerify];
canVerifyResult.CompletedParts.Enqueue((boogieUpdate.VerificationTask, completed));

if (Options.Get(CommonOptionBag.ProgressOption)) {
if (Options.Get(CommonOptionBag.ProgressOption) == CommonOptionBag.ProgressLevel.VerificationJobs) {
var token = BoogieGenerator.ToDafnyToken(false, boogieUpdate.VerificationTask.Split.Token);
var runResult = completed.Result;
var timeString = runResult.RunTime.ToString("g");
Options.OutputWriter.WriteLine(
$"Verified part #{boogieUpdate.VerificationTask.Split.SplitIndex}, {canVerifyResult.CompletedParts.Count}/{canVerifyResult.Tasks.Count} of {boogieUpdate.CanVerify.FullDafnyName}" +
$"Verified part #{boogieUpdate.VerificationTask.Split.SplitIndex}, {canVerifyResult.CompletedParts.Count}/{canVerifyResult.TaskCount} of {boogieUpdate.CanVerify.FullDafnyName}" +
$", on line {token.line}, " +
$"{DescribeOutcome(Compilation.GetOutcome(runResult.Outcome))}" +
$" (time: {timeString}, resource count: {runResult.ResourceCount})");
}
if (canVerifyResult.CompletedParts.Count == canVerifyResult.Tasks.Count) {
if (canVerifyResult.CompletedParts.Count == canVerifyResult.TaskCount) {
canVerifyResult.Finished.TrySetResult();
}
}
Expand All @@ -216,42 +216,53 @@ public async IAsyncEnumerable<CanVerifyResult> VerifyAllLazily(int? randomSeed)
canVerifies = FilterCanVerifies(canVerifies, out var line);
VerifiedAssertions = line != null;

var orderedCanVerifies = canVerifies.OrderBy(v => v.Tok.pos).ToList();
foreach (var canVerify in orderedCanVerifies) {
var results = new CliCanVerifyState();
canVerifyResults[canVerify] = results;
if (line != null) {
results.TaskFilter = t => KeepVerificationTask(t, line.Value);
}
int done = 0;

var shouldVerify = await Compilation.VerifyCanVerify(canVerify, results.TaskFilter, randomSeed);
if (!shouldVerify) {
orderedCanVerifies.Remove(canVerify);
}
}
var canVerifiesPerModule = canVerifies.ToList().GroupBy(c => c.ContainingModule).ToList();
foreach (var canVerifiesForModule in canVerifiesPerModule.
OrderBy(v => v.Key.Tok.pos)) {
var orderedCanVerifies = canVerifiesForModule.OrderBy(v => v.Tok.pos).ToList();
foreach (var canVerify in orderedCanVerifies) {
var results = new CliCanVerifyState();
canVerifyResults[canVerify] = results;
if (line != null) {
results.TaskFilter = t => KeepVerificationTask(t, line.Value);
}

int done = 0;
foreach (var canVerify in orderedCanVerifies) {
var results = canVerifyResults[canVerify];
try {
if (Options.Get(CommonOptionBag.ProgressOption)) {
await Options.OutputWriter.WriteLineAsync($"Verified {done}/{orderedCanVerifies.Count} symbols. Waiting for {canVerify.FullDafnyName} to verify.");
var shouldVerify = await Compilation.VerifyCanVerify(canVerify, results.TaskFilter, randomSeed);
if (!shouldVerify) {
canVerifies.ToList().Remove(canVerify);
}
await results.Finished.Task;
done++;
} catch (ProverException e) {
Compilation.Reporter.Error(MessageSource.Verifier, ResolutionErrors.ErrorId.none, canVerify.Tok, e.Message);
yield break;
} catch (OperationCanceledException) {

} catch (Exception e) {
Compilation.Reporter.Error(MessageSource.Verifier, ResolutionErrors.ErrorId.none, canVerify.Tok,
$"Internal error occurred during verification: {e.Message}\n{e.StackTrace}");
throw;
}
yield return new CanVerifyResult(canVerify, results.CompletedParts.Select(c => new VerificationTaskResult(c.Task, c.Result.Result)).ToList());

canVerifyResults.Remove(canVerify); // Free memory
foreach (var canVerify in orderedCanVerifies) {
var results = canVerifyResults[canVerify];
try {
if (Options.Get(CommonOptionBag.ProgressOption) > CommonOptionBag.ProgressLevel.None) {
await Options.OutputWriter.WriteLineAsync(
$"Verified {done}/{canVerifies.ToList().Count} symbols. Waiting for {canVerify.FullDafnyName} to verify.");
}

await results.Finished.Task;
done++;
} catch (ProverException e) {
Compilation.Reporter.Error(MessageSource.Verifier, ResolutionErrors.ErrorId.none, canVerify.Tok, e.Message);
yield break;
} catch (OperationCanceledException) {

} catch (Exception e) {
Compilation.Reporter.Error(MessageSource.Verifier, ResolutionErrors.ErrorId.none, canVerify.Tok,
$"Internal error occurred during verification: {e.Message}\n{e.StackTrace}");
throw;
}

yield return new CanVerifyResult(canVerify,
results.CompletedParts.Select(c => new VerificationTaskResult(c.Task, c.Result.Result)).ToList());

canVerifyResults.Remove(canVerify); // Free memory
Compilation.ClearCanVerifyCache(canVerify);
}
Compilation.ClearModuleCache(canVerifiesForModule.Key);
}
}

Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -11,15 +11,6 @@ Iterators.dfy(177,27): Error: assertion might not hold
Iterators.dfy(208,6): Error: an assignment to _new is only allowed to shrink the set
Iterators.dfy(212,20): Error: assertion might not hold
Iterators.dfy(234,20): Error: assertion might not hold
Iterators.dfy(251,9): Error: decreases clause might not decrease
Iterators.dfy(274,9): Error: decreases clause might not decrease
Iterators.dfy(284,31): Error: decreases clause might not decrease
Iterators.dfy(296,9): Error: cannot prove termination; try supplying a decreases clause
Iterators.dfy(317,9): Error: cannot prove termination; try supplying a decreases clause
Iterators.dfy(326,31): Error: cannot prove termination; try supplying a decreases clause
Iterators.dfy(343,9): Error: decreases clause might not decrease
Iterators.dfy(353,31): Error: cannot prove termination; try supplying a decreases clause
Iterators.dfy(370,9): Error: decreases clause might not decrease
Iterators.dfy(413,16): Error: this invariant could not be proved to be maintained by the loop
Related message: loop invariant violation
Iterators.dfy(414,21): Error: this invariant could not be proved to be maintained by the loop
Expand All @@ -40,5 +31,14 @@ Iterators.dfy(461,21): Error: this invariant could not be proved to be maintaine
Related message: loop invariant violation
Iterators.dfy(470,4): Error: possible violation of yield-ensures condition
Iterators.dfy(451,21): Related location: this proposition could not be proved
Iterators.dfy(251,9): Error: decreases clause might not decrease
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Why did the ordering change? Seems like a regression since we've been better about keeping these in order lately.

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@keyboardDrummer keyboardDrummer Oct 17, 2024

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It's unavoidable, since we want to verify one module at a time to be able to release memory after verifying that module. When nested modules occur, the contents of different modules can be intertwined.

method A

module Nested {
  method B
}

method C

We can do A,C,B or B,A,C, but we can no longer do A,B,C if we verify entire modules at a time.

Iterators.dfy(274,9): Error: decreases clause might not decrease
Iterators.dfy(284,31): Error: decreases clause might not decrease
Iterators.dfy(296,9): Error: cannot prove termination; try supplying a decreases clause
Iterators.dfy(317,9): Error: cannot prove termination; try supplying a decreases clause
Iterators.dfy(326,31): Error: cannot prove termination; try supplying a decreases clause
Iterators.dfy(343,9): Error: decreases clause might not decrease
Iterators.dfy(353,31): Error: cannot prove termination; try supplying a decreases clause
Iterators.dfy(370,9): Error: decreases clause might not decrease

Dafny program verifier finished with 35 verified, 30 errors
Original file line number Diff line number Diff line change
@@ -1,3 +1,5 @@
OpaqueFunctions.dfy(214,15): Error: assertion might not hold
OpaqueFunctions.dfy(229,19): Error: assertion might not hold
OpaqueFunctions.dfy(38,15): Error: assertion might not hold
OpaqueFunctions.dfy(69,7): Error: a precondition for this call could not be proved
OpaqueFunctions.dfy(35,15): Related location: this is the precondition that could not be proved
Expand All @@ -20,8 +22,6 @@ OpaqueFunctions.dfy(157,20): Error: assertion might not hold
OpaqueFunctions.dfy(160,20): Error: assertion might not hold
OpaqueFunctions.dfy(165,31): Error: assertion might not hold
OpaqueFunctions.dfy(181,12): Error: assertion might not hold
OpaqueFunctions.dfy(214,15): Error: assertion might not hold
OpaqueFunctions.dfy(229,19): Error: assertion might not hold
OpaqueFunctions.dfy(246,11): Error: assertion might not hold
OpaqueFunctions.dfy(261,11): Error: assertion might not hold
OpaqueFunctions.dfy(326,16): Error: assertion might not hold
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -4,7 +4,6 @@ Termination.dfy(126,16): Error: decreases expression must be bounded below by 0
Termination.dfy(255,34): Error: cannot prove termination; try supplying a decreases clause
Termination.dfy(296,2): Error: decreases expression might not decrease
Termination.dfy(361,46): Error: decreases clause might not decrease
Termination.dfy[TerminationRefinement1](441,5): Error: decreases clause might not decrease
Termination.dfy(534,2): Error: decreases expression might not decrease
Termination.dfy(542,2): Error: decreases expression might not decrease
Termination.dfy(549,2): Error: decreases expression might not decrease
Expand All @@ -21,5 +20,6 @@ Termination.dfy(730,2): Error: decreases expression might not decrease
Termination.dfy(806,2): Error: cannot prove termination; try supplying a decreases clause for the loop
Termination.dfy(1178,2): Error: cannot prove termination; try supplying a decreases clause for the loop
Termination.dfy(1194,2): Error: cannot prove termination; try supplying a decreases clause for the loop
Termination.dfy[TerminationRefinement1](441,5): Error: decreases clause might not decrease

Dafny program verifier finished with 108 verified, 23 errors
Original file line number Diff line number Diff line change
Expand Up @@ -4,7 +4,6 @@ Termination.dfy(126,16): Error: decreases expression must be bounded below by 0
Termination.dfy(255,34): Error: cannot prove termination; try supplying a decreases clause
Termination.dfy(296,2): Error: decreases expression might not decrease
Termination.dfy(361,46): Error: decreases clause might not decrease
Termination.dfy[TerminationRefinement1](441,5): Error: decreases clause might not decrease
Termination.dfy(534,2): Error: decreases expression might not decrease
Termination.dfy(542,2): Error: decreases expression might not decrease
Termination.dfy(549,2): Error: decreases expression might not decrease
Expand All @@ -22,5 +21,6 @@ Termination.dfy(806,2): Error: cannot prove termination; try supplying a decreas
Termination.dfy(923,2): Error: cannot prove termination; try supplying a decreases clause for the loop
Termination.dfy(1178,2): Error: cannot prove termination; try supplying a decreases clause for the loop
Termination.dfy(1194,2): Error: cannot prove termination; try supplying a decreases clause for the loop
Termination.dfy[TerminationRefinement1](441,5): Error: decreases clause might not decrease

Dafny program verifier finished with 107 verified, 24 errors
Original file line number Diff line number Diff line change
@@ -1,9 +1,9 @@
TypeInferenceRefresh.dfy(445,11): Warning: the modify statement with a block statement is deprecated
TypeInferenceRefresh.dfy(807,4): Warning: this branch is redundant
TypeInferenceRefresh.dfy(102,31): Error: value does not satisfy the subset constraints of 'SubsetType'
TypeInferenceRefresh.dfy(107,31): Error: value does not satisfy the subset constraints of 'SubsetType'
TypeInferenceRefresh.dfy(145,30): Error: element might not be in domain
TypeInferenceRefresh.dfy(216,26): Error: result of operation might violate newtype constraint for 'int8'
TypeInferenceRefresh.dfy(102,31): Error: value does not satisfy the subset constraints of 'SubsetType'
TypeInferenceRefresh.dfy(107,31): Error: value does not satisfy the subset constraints of 'SubsetType'
TypeInferenceRefresh.dfy(630,40): Error: value does not satisfy the subset constraints of 'nat'
TypeInferenceRefresh.dfy(630,43): Error: value does not satisfy the subset constraints of 'nat'
TypeInferenceRefresh.dfy(630,47): Error: value does not satisfy the subset constraints of 'nat'
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -36,7 +36,6 @@ git-issue-977.dfy(71,4): Info: ensures RicochetOrd(m, num)
git-issue-977.dfy(110,9): Info: Some instances of this call are not inlined.
git-issue-977.dfy(143,9): Info: Some instances of this call are not inlined.
git-issue-977.dfy(162,2): Info: Some instances of this call are not inlined.
git-issue-977.dfy(220,11): Info: Some instances of this call are not inlined.
git-issue-977.dfy(39,11): Error: assertion might not hold
git-issue-977.dfy(14,20): Related location: this proposition could not be proved
git-issue-977.dfy(9,7): Related location: this proposition could not be proved
Expand All @@ -46,5 +45,6 @@ git-issue-977.dfy(9,7): Related location: this proposition could not be proved
git-issue-977.dfy(43,11): Error: assertion might not hold
git-issue-977.dfy(30,20): Related location: this proposition could not be proved
git-issue-977.dfy(9,7): Related location: this proposition could not be proved
git-issue-977.dfy(220,11): Info: Some instances of this call are not inlined.

Dafny program verifier finished with 20 verified, 3 errors
Original file line number Diff line number Diff line change
@@ -1,4 +1,4 @@
// RUN: %verify --progress --cores 1 "%s" > "%t"
// RUN: %verify --progress Symbol --cores 1 "%s" > "%t"
// RUN: %OutputCheck --file-to-check "%t" "%s"
// CHECK-L:Verified 0/5 symbols. Waiting for smallPrime to verify.
// CHECK-L:Verified 2/5 symbols. Waiting for posIdMeth to verify.
Expand Down
Original file line number Diff line number Diff line change
@@ -1,19 +1,19 @@

Dafny program verifier finished with 0 verified, 0 errors
filter-symbol.dfy(12,29): Error: a postcondition could not be proved on this return path
filter-symbol.dfy(12,23): Related location: this is the postcondition that could not be proved
filter-symbol.dfy(14,27): Error: a postcondition could not be proved on this return path
filter-symbol.dfy(14,21): Related location: this is the postcondition that could not be proved
filter-symbol.dfy(12,29): Error: a postcondition could not be proved on this return path
filter-symbol.dfy(12,23): Related location: this is the postcondition that could not be proved
filter-symbol.dfy(19,29): Error: a postcondition could not be proved on this return path
filter-symbol.dfy(19,23): Related location: this is the postcondition that could not be proved

Dafny program verifier finished with 0 verified, 3 errors
filter-symbol.dfy(12,29): Error: a postcondition could not be proved on this return path
filter-symbol.dfy(12,23): Related location: this is the postcondition that could not be proved
filter-symbol.dfy(19,29): Error: a postcondition could not be proved on this return path
filter-symbol.dfy(19,23): Related location: this is the postcondition that could not be proved
filter-symbol.dfy(21,27): Error: a postcondition could not be proved on this return path
filter-symbol.dfy(21,21): Related location: this is the postcondition that could not be proved
filter-symbol.dfy(19,29): Error: a postcondition could not be proved on this return path
filter-symbol.dfy(19,23): Related location: this is the postcondition that could not be proved

Dafny program verifier finished with 0 verified, 3 errors
filter-symbol.dfy(12,29): Error: a postcondition could not be proved on this return path
Expand Down
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