public WhilePCNode(ArmadaPC i_pc, NextRoutine i_nextRoutineWhenTrue, NextRoutine i_nextRoutineWhenFalse, PCNode i_successorWhenTrue,
PCNode i_successorWhenFalse) : base(i_pc)
{
nextRoutineWhenTrue = i_nextRoutineWhenTrue;
nextRoutineWhenFalse = i_nextRoutineWhenFalse;
successorWhenTrue = i_successorWhenTrue;
successorWhenFalse = i_successorWhenFalse;
}
public bool IsNonyieldingPC(ArmadaPC pc)
{
if (pc == null)
{
return(false);
}
var method = allMethodsInfo.LookupMethod(pc.methodName);
return(method == null ? false : method.IsNonyieldingPC(pc));
}
public string GetStoreBufferEntry(string val_new, ArmadaPC pc)
{
var loc = GetStoreBufferLocation();
if (loc == null)
{
return(null);
}
return($"Armada_StoreBufferEntry({loc}, {AH.GetPrimitiveValueConstructorName(type)}({val_new}), {pc.ToString()})");
}
public string GetNameForPC(ArmadaPC pc)
{
string labelStr = GetLabelForPC(pc);
if (labelStr != null)
{
return(labelStr);
}
return(pc.instructionCount.ToString());
}
public ArmadaPC GenerateOnePC()
{
int pcVal = numPCs;
++numPCs;
var pc = new ArmadaPC(symbols, method.Name, pcVal);
symbols.AssociateLabelWithPC(pcVal.ToString(), pc);
return(pc);
}
private bool AdjacentPC(ArmadaPC lhs, ArmadaPC rhs)
{
if (lhs.methodName == null || rhs.methodName == null)
{
Console.WriteLine("Invalid PC");
return(false);
}
return(lhs.methodName == rhs.methodName && lhs.instructionCount + 1 == rhs.instructionCount);
}
public AtomicPathPrefix(AtomicSpec i_atomicSpec, ArmadaPC pc)
{
atomicSpec = i_atomicSpec;
nextRoutines = new List <NextRoutine>();
tau = false;
startPC = endPC = pc;
startType = endType = atomicSpec.GetPCAtomicType(pc);
extensions = new List <AtomicPathPrefix>();
path = null;
}
public EnablingConstraintCollector GetEnablingConstraintCollector(ArmadaPC pc)
{
if (constraints.ContainsKey(pc))
{
return(constraints[pc]);
}
else
{
return(null);
}
}
public string GetLabelForPC(ArmadaPC pc)
{
if (pcToLabelMap.ContainsKey(pc))
{
return(pcToLabelMap[pc]);
}
else
{
return(null);
}
}
public void AssociateLabelWithPC(string labelStr, ArmadaPC pc)
{
var fullLabelStr = pc.methodName + "_" + labelStr;
if (methodAndLabelToPCMap.ContainsKey(fullLabelStr))
{
AH.PrintError(prog, $"ERROR: More than one label named {labelStr} in method {pc.methodName}");
}
methodAndLabelToPCMap[fullLabelStr] = pc;
pcToLabelMap[pc] = labelStr;
}
public MethodInfo(Program i_prog, ArmadaSymbolTable i_symbols, Method i_method)
{
prog = i_prog;
symbols = i_symbols;
method = i_method;
numPCs = 0;
constraints = new Dictionary <ArmadaPC, EnablingConstraintCollector>();
returnPC = null;
nonyieldingPCs = new HashSet <ArmadaPC>();
parsedBody = null;
atomicCallsAndReturns = false;
}
private ArmadaPC GetRoot(ArmadaPC key, Dictionary <ArmadaPC, ArmadaPC> unionFind)
{
if (unionFind.ContainsKey(key))
{
unionFind[key] = GetRoot(unionFind[key], unionFind);
}
else
{
return(key);
}
return(unionFind[key]);
}
public void AddEnablingConstraint(Program prog, ArmadaPC pc, Expression e)
{
if (!constraints.ContainsKey(pc))
{
constraints[pc] = new EnablingConstraintCollector(prog);
}
var constraintCollector = constraints[pc];
var context = new EnablingConstraintResolutionContext(constraintCollector, method.Name, symbols);
var rvalue = context.ResolveAsRValue(e);
constraintCollector.AddConjunct(rvalue.UndefinedBehaviorAvoidance);
constraintCollector.AddConjunct(rvalue.Val);
}
private static PCNode GeneratePCStructureForMethodWithNoBody(ArmadaSymbolTable symbols, MethodInfo methodInfo, HashSet <ArmadaPC> loopHeads)
{
Method method = methodInfo.method;
var startPC = new ArmadaPC(symbols, method.Name, 0);
var midPC = new ArmadaPC(symbols, method.Name, 1);
var endPC = new ArmadaPC(symbols, method.Name, 2);
PCNode endNode = new ReturningPCNode(endPC);
PCNode loopRestartNode = new LoopRestartPCNode(midPC);
PCNode midNode = new WhilePCNode(midPC, method.externContinueNextRoutine, method.externEndNextRoutine, loopRestartNode, endNode);
PCNode startNode = new NormalPCNode(startPC, method.externStartNextRoutine, midNode);
loopHeads.Add(midPC);
return(new StartingPCNode(startPC, startNode));
}
public NextRoutine(Program i_prog, ArmadaSymbolTable i_symbols, NextType i_nextType, MethodInfo i_methodInfo,
ArmadaStatement i_armadaStatement, Statement i_stmt, ArmadaPC i_startPC, ArmadaPC i_endPC,
List <NextFormal> i_formals, string i_nameSuffix, bool i_undefinedBehavior, bool i_stopping)
{
prog = i_prog;
symbols = i_symbols;
nextType = i_nextType;
methodInfo = i_methodInfo;
armadaStatement = i_armadaStatement;
stmt = i_stmt;
startPC = i_startPC;
endPC = i_endPC;
formals = new List <NextFormal>(i_formals);
nameSuffix = i_nameSuffix;
undefinedBehavior = i_undefinedBehavior;
stopping = i_stopping;
}
public NextRoutineConstructor(Program i_prog, ArmadaSymbolTable i_symbols, NextType i_nextType, MethodInfo i_methodInfo,
ArmadaStatement i_armadaStatement, Statement i_stmt, ArmadaPC i_startPC, ArmadaPC i_endPC)
{
prog = i_prog;
symbols = i_symbols;
nextType = i_nextType;
validDefinedStepBuilder = new PredicateBuilder(i_prog, true);
validUndefinedStepBuilder = new PredicateBuilder(i_prog, false);
getNextStateBuilder = new ExpressionBuilder(i_prog);
methodInfo = i_methodInfo;
method = methodInfo == null ? null : methodInfo.method;
armadaStatement = i_armadaStatement;
stmt = i_stmt;
startPC = i_startPC;
endPC = i_endPC;
formals = new List <NextFormal>();
valid = true;
hasUndefinedBehaviorAvoidanceConstraint = false;
definedBehaviorNextRoutine = null;
undefinedBehaviorNextRoutine = null;
s = ReserveVariableName("s");
entry = ReserveVariableName("entry");
tid = ReserveVariableName("tid");
t = ReserveVariableName("t");
locv = ReserveVariableName("locv");
if (startPC != null)
{
AddConjunct($"{t}.pc.{startPC}?");
AddConjunct($"{t}.top.Armada_StackFrame_{startPC.methodName}?");
if (methodInfo != null)
{
var constraints = methodInfo.GetEnablingConstraintCollector(startPC);
if (constraints != null && !constraints.Empty)
{
AddConjunct($"Armada_EnablingConditions_{startPC}(s, tid)");
}
}
AddConjunct("Armada_UniversalStepConstraint(s, tid)");
}
}
///////////////////////////////////////////////////////////////////////
// PC TYPES
///////////////////////////////////////////////////////////////////////
public PCAtomicType GetPCAtomicType(ArmadaPC pc)
{
if (pc == null)
{
return(PCAtomicType.Yielding);
}
if (recurrentPCs.Contains(pc))
{
return(PCAtomicType.Recurrent);
}
if (nonyieldingPCs.Contains(pc))
{
return(PCAtomicType.Nonyielding);
}
else
{
return(PCAtomicType.Yielding);
}
}
public void ParseMethodBody(ArmadaSymbolTable symbols)
{
var parse = new ParseInfo(prog, symbols, this);
parsedBody = ArmadaStatement.ParseStatement(parse, method.Body);
var startPC = GenerateOnePC();
returnPC = parsedBody.AssignPCs(startPC);
ArmadaStatement.ComputeNonyieldingPCs(parsedBody, nonyieldingPCs);
symbols.AssociateLabelWithPC("Start", startPC);
symbols.AssociateLabelWithPC("End", returnPC);
foreach (var statement in parsedBody)
{
statement.AssociateLabelsWithPCs();
statement.GenerateEnablingConstraints();
}
}
///////////////////////////////////////////////////////////////////////
// FINDING RECURRENT PCS
///////////////////////////////////////////////////////////////////////
/// <summary>
/// In CheckForFiniteNonyieldingPathBetween, we only care about
/// paths that reach end before visiting any other node twice
/// (since if it visits another node twice, it's potentially
/// infinite). So, we keep track of nodes we've already visited
/// and don't visit them again.
/// </summary>
private bool CheckForFiniteNonyieldingPathBetween(ArmadaPC start, ArmadaPC end, HashSet <ArmadaPC> alreadyVisited)
{
if (start == null || end == null)
{
return(false);
}
if (!nonyieldingPCs.Contains(start))
{
return(false);
}
List <NextRoutine> nextRoutines;
if (!pcToNextRoutines.TryGetValue(start, out nextRoutines))
{
return(false);
}
foreach (var nextRoutine in nextRoutines)
{
var nextPC = nextRoutine.endPC;
if (nextPC.Equals(end))
{
return(true);
}
if (alreadyVisited.Contains(nextPC))
{
continue;
}
alreadyVisited.Add(nextPC);
if (CheckForFiniteNonyieldingPathBetween(nextPC, end, alreadyVisited))
{
return(true);
}
alreadyVisited.Remove(nextPC);
}
return(false);
}
public string UpdateTotalStateWithStoreBufferEntry(ResolutionContext context, IConstraintCollector constraintCollector,
string val_new, ArmadaPC pc)
{
if (NoTSO())
{
return(UpdateTotalStateLocationDirectly(context, constraintCollector, val_new));
}
if (!AH.IsPrimitiveType(type))
{
context.Fail(tok, "Can't do TSO write to non-primitive type; try using ::= instead of :=");
return(null);
}
var entry = GetStoreBufferEntry(val_new, pc);
if (entry == null)
{
context.Fail(tok, "Can't do a TSO write to that location; try using ::= instead of :=");
return(null);
}
return($"Armada_AppendToThreadStoreBuffer({context.GetLValueState()}, {context.tid}, {entry})");
}
private bool DoesNonyieldingPathBetweenPCsExist(ArmadaPC start, ArmadaPC end)
{
var alreadyVisited = new HashSet <ArmadaPC>();
return(CheckForFiniteNonyieldingPathBetween(start, end, alreadyVisited));
}
public AtomicPathPrefix(AtomicSpec i_atomicSpec, List <NextRoutine> i_nextRoutines, bool i_tau, AtomicPathPrefix parent)
{
atomicSpec = i_atomicSpec;
nextRoutines = new List <NextRoutine>(i_nextRoutines);
tau = i_tau;
startPC = nextRoutines[0].startPC;
endPC = nextRoutines[nextRoutines.Count - 1].endPC;
startType = atomicSpec.GetPCAtomicType(startPC);
endType = nextRoutines[nextRoutines.Count - 1].Stopping ? PCAtomicType.Stopping : atomicSpec.GetPCAtomicType(endPC);
extensions = new List <AtomicPathPrefix>();
path = null;
if (parent != null)
{
parent.AddExtension(this);
}
if (tau)
{
name = "Tau";
}
else
{
name = UndefinedBehavior ? "UB_" : "";
name += $"From_{startPC.methodName}_{startPC.Name}";
// It's possible for two atomic paths to have the same start
// and end PCs. But, every path has to have a distinct name,
// so we sometimes have to name a path with more than just the
// start and end PCs.
//
// One way for two atomic paths with the same start and end
// PCs to differ is via returning to different PCs. For
// instance, consider the following code:
//
// method {:atomic} A {
// S1;
// label L:
// S2;
// }
//
// method B {
// atomic {
// A();
// A();
// A();
// }
// }
//
// Here, there are two ways to get from label L to label L:
// (1) by returning from B's first call to A and then making
// B's second call to A, and (2) by returning from B's second
// call to A and then making B's third call to A. So, to make
// sure such paths have different names, we include in the
// name every returned-to PC in a step other than the last one
// in the path.
//
// Another way for two atomic paths with the same start and
// end PCs to differ is via branch outcomes. For instance,
// consider the following code:
//
// atomic {
// if P {
// S1;
// }
// S2;
// }
//
// Here, there are two ways to get from the beginning to the
// end: via the true branch of the if (passing through
// statement S1) or via the false branch. So we distinguish
// the names of such paths by the branch outcomes.
bool justBranched = false;
for (var i = 0; i < nextRoutines.Count; ++i)
{
var nextRoutine = nextRoutines[i];
if (i < nextRoutines.Count - 1 && nextRoutine.nextType == NextType.Return)
{
var returnToPC = nextRoutine.endPC;
name += $"_Via_{returnToPC.methodName}_{returnToPC.Name}";
justBranched = false;
}
bool branchOutcome;
if (nextRoutine.TryGetBranchOutcome(out branchOutcome))
{
if (!justBranched)
{
name += "_";
}
name += (branchOutcome ? "T" : "F");
justBranched = true;
}
}
if (endPC == null)
{
name += "_to_exit";
}
else
{
name += $"_To_{endPC.methodName}_{endPC.Name}";
}
}
}
public IEnumerable <AtomicPathPrefix> RootPathPrefixesByPC(ArmadaPC pc)
{
return(rootPathPrefixesByPC[pc]);
}
////////////////////////////////////////////////////////////////////////
/// PC map
////////////////////////////////////////////////////////////////////////
bool MakePCMap()
{
startPC = pgp.symbolsLow.GetPCForMethodAndLabel(strategy.StartLabel.val);
if (startPC == null)
{
AH.PrintError(pgp.prog, $"You specified a start label for combining of {strategy.StartLabel.val}, but that label doesn't exist in level {pgp.mLow.Name}. Remember to prefix label names with the method name and an underscore, e.g., use main_lb1 if you have label lb1: in method main.");
return(false);
}
endPC = pgp.symbolsLow.GetPCForMethodAndLabel(strategy.EndLabel.val);
if (endPC == null)
{
AH.PrintError(pgp.prog, $"You specified an end label for combining of {strategy.EndLabel.val}, but that label doesn't exist in level {pgp.mLow.Name}. Remember to prefix label names with the method name and an underscore, e.g., use main_lb1 if you have label lb1: in method main.");
return(false);
}
if (endPC.methodName != startPC.methodName)
{
AH.PrintError(pgp.prog, $"The start and end labels you provided for combining aren't from the same method in {pgp.mLow.Name}. The start label {strategy.StartLabel.val} is in method {startPC.methodName} and the end label {strategy.EndLabel.val} is in method {endPC.methodName}.");
return(false);
}
if (endPC.instructionCount <= startPC.instructionCount)
{
AH.PrintError(pgp.prog, $"The end label you provided for combining ({strategy.EndLabel.val}) isn't after the start label you provided for combining ({strategy.StartLabel.val}).");
return(false);
}
singlePC = pgp.symbolsHigh.GetPCForMethodAndLabel(strategy.SingleLabel.val);
if (singlePC == null)
{
AH.PrintError(pgp.prog, $"You specified a single label for combining of {strategy.SingleLabel.val}, but that label doesn't exist in level {pgp.mHigh.Name}. Remember to prefix label names with the method name and an underscore, e.g., use main_lb1 if you have label lb1: in method main.");
return(false);
}
if (singlePC.methodName != startPC.methodName)
{
AH.PrintError(pgp.prog, $"The start and end labels you provided for combining aren't from the same method as the single label you provided. That is, {strategy.StartLabel.val} and {strategy.EndLabel.val} are both from method {startPC.methodName}, but the single label {strategy.SingleLabel.val} is from method {singlePC.methodName}.");
return(false);
}
if (singlePC.instructionCount != startPC.instructionCount)
{
AH.PrintError(pgp.prog, $"The start label you provided isn't at the same position in its method as the single label you provided. That is, {strategy.StartLabel.val} is preceded by {startPC.instructionCount} instructions in {pgp.mLow.Name}, but {strategy.SingleLabel.val} is preceded by {singlePC.instructionCount} instructions in {pgp.mHigh.Name}.");
return(false);
}
pcMap = new Dictionary <ArmadaPC, ArmadaPC>();
var pcs = new List <ArmadaPC>();
pgp.symbolsLow.AllMethods.AppendAllPCs(pcs);
foreach (var pc in pcs)
{
if (pc.methodName != startPC.methodName)
{
pcMap[pc] = pc.CloneWithNewSymbolTable(pgp.symbolsHigh);
}
else if (pc.instructionCount < startPC.instructionCount)
{
pcMap[pc] = pc.CloneWithNewSymbolTable(pgp.symbolsHigh);
}
else if (pc.instructionCount == startPC.instructionCount)
{
pcMap[pc] = singlePC;
}
else if (pc.instructionCount <= endPC.instructionCount)
{
pcMap[pc] = new ArmadaPC(pgp.symbolsHigh, pc.methodName, singlePC.instructionCount + 1);
}
else
{
pcMap[pc] = new ArmadaPC(pgp.symbolsHigh, pc.methodName, pc.instructionCount + startPC.instructionCount - endPC.instructionCount);
}
}
ExtendPCMapWithExternalAndStructsMethods();
GenerateNextRoutineMap(false);
return(true);
}
public NormalPCInfo(ArmadaPC pc) : base(pc)
{
}
public ForkSitePCInfo(ArmadaPC pc) : base(pc)
{
}
public CallSitePCInfo(ArmadaPC pc) : base(pc)
{
}
public ReturnSitePCInfo(ArmadaPC pc) : base(pc)
{
}
public ReturningPCNode(ArmadaPC i_pc) : base(i_pc)
{
}
public LoopRestartPCNode(ArmadaPC i_pc) : base(i_pc)
{
}