private bool IsRelevant(Bpl.Cmd cmd)
{
Bpl.AssertCmd assertCmd = cmd as Bpl.AssertCmd;
if (assertCmd == null)
{
return(false);
}
string sourceFile = Bpl.QKeyValue.FindStringAttribute(assertCmd.Attributes, "sourceFile");
if (sourceFile == null)
{
return(false);
}
string[] ds = sourceFile.Split('\\');
if (sourceFile != fileName && ds[ds.Length - 1] != fileName)
{
return(false);
}
int sourceLine = Bpl.QKeyValue.FindIntAttribute(assertCmd.Attributes, "sourceLine", -1);
Debug.Assert(sourceLine != -1);
if (sourceLine != lineNumber)
{
return(false);
}
return(true);
}
void PredicateCmd(Expr p, Expr pDom, List<Block> blocks, Block block, Cmd cmd, out Block nextBlock) {
var cCmd = cmd as CallCmd;
if (cCmd != null && !useProcedurePredicates(cCmd.Proc)) {
if (p == null) {
block.Cmds.Add(cmd);
nextBlock = block;
return;
}
var trueBlock = new Block();
blocks.Add(trueBlock);
trueBlock.Label = block.Label + ".call.true";
trueBlock.Cmds.Add(new AssumeCmd(Token.NoToken, p));
trueBlock.Cmds.Add(cmd);
var falseBlock = new Block();
blocks.Add(falseBlock);
falseBlock.Label = block.Label + ".call.false";
falseBlock.Cmds.Add(new AssumeCmd(Token.NoToken, Expr.Not(p)));
var contBlock = new Block();
blocks.Add(contBlock);
contBlock.Label = block.Label + ".call.cont";
block.TransferCmd =
new GotoCmd(Token.NoToken, new List<Block> { trueBlock, falseBlock });
trueBlock.TransferCmd = falseBlock.TransferCmd =
new GotoCmd(Token.NoToken, new List<Block> { contBlock });
nextBlock = contBlock;
} else {
PredicateCmd(p, pDom, block.Cmds, cmd);
nextBlock = block;
}
}
public static Bpl.StmtList BuildStmtList(Bpl.Cmd cmd, Bpl.TransferCmd tcmd)
{
Bpl.StmtListBuilder builder = new Bpl.StmtListBuilder();
builder.Add(cmd);
builder.Add(tcmd);
return(builder.Collect(Bpl.Token.NoToken));
}
public bool isSyncCall(bpl.Cmd cmd)
{
if (!(cmd is bpl.CallCmd))
{
return(false);
}
var callCmd = cmd as bpl.CallCmd;
return(!callCmd.IsAsync);
}
public bool isAtomicEnd(bpl.Cmd cmd)
{
if (cmd == null)
{
return(false);
}
if (!(cmd is bpl.CallCmd))
{
return(false);
}
return((cmd as bpl.CallCmd).callee == atomicEndProc);
}
public Cmd CopyCmd(Cmd cmd)
{
Contract.Requires(cmd != null);
Contract.Ensures(Contract.Result<Cmd>() != null);
if (Subst == null) {
return cmd;
} else if (OldSubst == null) {
return Substituter.Apply(Subst, cmd);
} else {
return Substituter.ApplyReplacingOldExprs(Subst, OldSubst, cmd);
}
}
public bool isYield(bpl.Cmd cmd)
{
if (cmd == null)
{
return(false);
}
if (!(cmd is bpl.CallCmd))
{
return(false);
}
return((cmd as bpl.CallCmd).callee == yieldProc);
}
public override Bpl.CmdSeq VisitCmdSeq(Bpl.CmdSeq cmdSeq)
{
Bpl.CmdSeq newCmdSeq = new Bpl.CmdSeq();
for (int i = 0; i < cmdSeq.Length; i++)
{
Bpl.Cmd cmd = cmdSeq[i];
if (IsRelevant(cmd))
{
newCmdSeq.Add(new Bpl.AssertCmd(cmd.tok, Bpl.Expr.False));
}
newCmdSeq.Add(cmd);
}
return(newCmdSeq);
}
public int readInvariantLabel(bpl.Cmd cmd)
{
var callCmd = cmd as bpl.CallCmd;
if (callCmd == null)
{
throw new ConcurrentHoudiniException("[Context::readInvariantLabel] Not a call command");
}
var args = getAttrParams(callCmd.Attributes, invariantAttr);
if (args.Count() < 1 || !(args[0] is bpl.LiteralExpr))
{
throw new ConcurrentHoudiniException("[Context::readInvariantLabel] Ill formed parameter");
}
var numExpr = args[0] as bpl.LiteralExpr;
return(numExpr.asBigNum.ToInt);
}
public bpl.QKeyValue getAssumeAttrFromCmd(bpl.Cmd cmd)
{
if (!isYield(cmd) && !isR(cmd))
{
return(null);
}
var attr = (cmd as bpl.CallCmd).Attributes;
while (attr != null)
{
if (attr.Key == yieldAttr)
{
var num = (attr.Params[0] as bpl.LiteralExpr).asBigNum;
var paramList = new List <object>();
paramList.Add(new bpl.LiteralExpr(bpl.Token.NoToken, num));
return(new bpl.QKeyValue(bpl.Token.NoToken, invariantAttr, paramList, null));
}
attr = attr.Next;
}
return(null);
}
/// <summary>
/// The abstract transition relation.
/// 'cmd' is allowed to be a StateCmd.
/// </summary>
static NativeLattice.Element Step(NativeLattice lattice, Cmd cmd, NativeLattice.Element elmt)
{
Contract.Requires(lattice != null);
Contract.Requires(cmd != null);
Contract.Requires(elmt != null);
Contract.Ensures(Contract.Result<NativeLattice.Element>() != null);
if (cmd is AssignCmd) { // parallel assignment
var c = (AssignCmd)cmd;
elmt = lattice.Update(elmt, c.AsSimpleAssignCmd);
} else if (cmd is HavocCmd) {
var c = (HavocCmd)cmd;
foreach (IdentifierExpr id in c.Vars) {
Contract.Assert(id != null);
elmt = lattice.Eliminate(elmt, id.Decl);
}
} else if (cmd is PredicateCmd) {
var c = (PredicateCmd)cmd;
var conjuncts = new List<Expr>();
foreach (var ee in Conjuncts(c.Expr)) {
Contract.Assert(ee != null);
elmt = lattice.Constrain(elmt, ee);
}
} else if (cmd is StateCmd) {
var c = (StateCmd)cmd;
// Iterate the abstract transition on all the commands in the desugaring of the call
foreach (Cmd callDesug in c.Cmds) {
Contract.Assert(callDesug != null);
elmt = Step(lattice, callDesug, elmt);
}
// Project out the local variables of the StateCmd
foreach (Variable local in c.Locals) {
Contract.Assert(local != null);
elmt = lattice.Eliminate(elmt, local);
}
} else if (cmd is SugaredCmd) {
var c = (SugaredCmd)cmd;
elmt = Step(lattice, c.Desugaring, elmt);
} else if (cmd is CommentCmd) {
// skip
} else {
Contract.Assert(false); // unknown command
}
return elmt;
}
public bpl.Program split(bpl.Program prog)
{
originalProgram = prog;
////////////////// First identify the thread entries in the program ////////////////////
// A procedure is a thread entry if there is any async call to it
HashSet <string> threadEntries = new HashSet <string>();
var impls = new Func <bpl.Program, IEnumerable <bpl.Implementation> >(p => from impl in p.TopLevelDeclarations where impl is bpl.Implementation select impl as bpl.Implementation);
foreach (var impl in impls(originalProgram))
{
var cmdsRaw = from blk in impl.Blocks select blk.Cmds;
var cmds = cmdsRaw.Aggregate(new List <bpl.Cmd>(), (curCmds, nextList) => { curCmds.AddRange(nextList); return(curCmds); });
var asyncCalls = from cmd in cmds where con.isAsyncCall(cmd as bpl.Cmd) select cmd;
foreach (bpl.Cmd asyncCall in asyncCalls)
{
threadEntries.Add((asyncCall as bpl.CallCmd).callee);
}
}
// Finally add the entry function also as a thread entry.
threadEntries.Add(con.entryFunc);
//////////////// Next, identify all the procedures belonging to each thread ////////////
Dictionary <string, HashSet <string> > threadToProcs = new Dictionary <string, HashSet <string> >();
// This is done in two steps.
// First step: Find all non-async calls in each procedure.
var procToCalls = new Dictionary <string, HashSet <string> >();
//impls = from impl in prog.TopLevelDeclarations where impl is bpl.Implementation select impl as bpl.Implementation;
foreach (var impl in impls(originalProgram))
{
procToCalls[impl.Name] = new HashSet <string>();
var cmdsRaw = from blk in impl.Blocks select blk.Cmds;
var cmds = cmdsRaw.Aggregate(new List <bpl.Cmd>(), (curCmds, nextList) => { curCmds.AddRange(nextList); return(curCmds); });
var syncCalls = from cmd in cmds where con.isSyncCall(cmd as bpl.Cmd) select cmd;
foreach (bpl.Cmd syncCall in syncCalls)
{
procToCalls[impl.Name].Add((syncCall as bpl.CallCmd).callee);
}
}
// Second step: Find all procedures in each thread.
foreach (var thr in threadEntries)
{
threadToProcs[thr] = new HashSet <string>();
}
foreach (var thr in threadEntries)
{
findReachable(procToCalls, thr, threadToProcs[thr]);
}
//DEBUGGING
if (dbg)
{
System.Console.WriteLine("Threads in the original program:");
foreach (var iter in threadToProcs)
{
System.Console.Write(iter.Key + ": ");
foreach (var proc in iter.Value)
{
System.Console.Write(proc + " ");
}
System.Console.WriteLine();
}
}
// [Optional]
// Remove unreachable procs.
// These procedures are neither reachable from Main, nor from a thread entry. They can obviously not be called in any execution.
var reachableProcs = new HashSet <string>();
foreach (var vals in threadToProcs.Values)
{
foreach (var proc in vals)
{
reachableProcs.Add(proc);
}
}
foreach (var val in threadToProcs.Keys)
{
reachableProcs.Add(val);
}
removeUnreachable(reachableProcs);
//////////////// Finally, Actually split the procedures when needed //////////////////
// For every procedure, find out how many threads contain it. We need as many copies of
// that procedure.
// Note: We do not want to duplicate procedures without implementation.
//impls = from impl in prog.TopLevelDeclarations where impl is bpl.Implementation select impl as bpl.Implementation;
var implNames = from impl in impls(originalProgram) select impl.Name;
Dictionary <string, int> procCopies = new Dictionary <string, int>();
var procs = from proc in originalProgram.TopLevelDeclarations where proc is bpl.Procedure select proc as bpl.Procedure;
foreach (var proc in procs)
{
procCopies[proc.Name] = 0;
}
foreach (var iter in threadToProcs)
{
foreach (var proc in iter.Value)
{
if (implNames.Contains(proc))
{
procCopies[proc]++;
}
}
}
// Now duplicate
// The new procedures and implementations for each thread
// thread name --> (old procedure name --> new procedure)
var newProcsPerThread = new Dictionary <string, Dictionary <string, bpl.Procedure> >();
// thread name --> (old procedure name --> new implementation)
var newImplsPerThread = new Dictionary <string, Dictionary <string, bpl.Implementation> >();
// old name --> proc, old name --> impl
var oldNameToImpl = new Dictionary <string, bpl.Implementation>();
foreach (var impl in impls(originalProgram))
{
oldNameToImpl[impl.Name] = impl;
}
var oldNameToProc = new Dictionary <string, bpl.Procedure>();
foreach (var proc in procs)
{
oldNameToProc[proc.Name] = proc;
}
foreach (var elem in threadToProcs)
{
string threadName = elem.Key;
newProcsPerThread[threadName] = new Dictionary <string, bpl.Procedure>();
newImplsPerThread[threadName] = new Dictionary <string, bpl.Implementation>();
foreach (var procName in elem.Value)
{
if (procCopies[procName] > 1)
{
// We will duplicate this procedure.
// Make a copy of the procedure and implementation
var dup = new cba.Util.FixedDuplicator();
var impl = (bpl.Implementation)dup.VisitDeclaration(oldNameToImpl[procName]);
var proc = (bpl.Procedure)dup.VisitDeclaration(oldNameToProc[procName]);
impl.Proc = proc;
// Rename the new instances using thread id.
impl.Name = con.getSplitProcName(procName);
proc.Name = con.getSplitProcName(procName);
var origProcAttr = con.originalProcAttr(procName);
origProcAttr.Next = proc.Attributes;
proc.Attributes = origProcAttr;
// Also add an attribute to the definition specifying the thread.
var threadAttr = con.getThreadAttr(threadName);
threadAttr.Next = proc.Attributes;
proc.Attributes = threadAttr;
//add to duplicated procedures/impls
newProcsPerThread[threadName][procName] = proc;
newImplsPerThread[threadName][procName] = impl;
//Add to the program
originalProgram.AddTopLevelDeclaration(proc);
originalProgram.AddTopLevelDeclaration(impl);
var s1 = new HashSet <string>();
var s2 = new HashSet <string>();
foreach (var im in originalProgram.TopLevelDeclarations.OfType <bpl.Implementation>())
{
s1.Add(im.Name);
}
foreach (var im in impls(originalProgram))
{
s2.Add(im.Name);
}
// We have split away the procedure calls for one thread.
procCopies[procName]--;
}
else if (procCopies[procName] == 1)
{
//We still need to rename this procedure
var impl = oldNameToImpl[procName];
var proc = oldNameToProc[procName];
//rename the new instances using thread id.
impl.Name = con.getSplitProcName(procName);
proc.Name = con.getSplitProcName(procName);
var origProcAttr = con.originalProcAttr(procName);
origProcAttr.Next = proc.Attributes;
proc.Attributes = origProcAttr;
// Also add an attribute to the definition specifying the thread.
var threadAttr = con.getThreadAttr(threadName);
threadAttr.Next = proc.Attributes;
proc.Attributes = threadAttr;
//add to duplicated procedures/impls
newProcsPerThread[threadName][procName] = proc;
newImplsPerThread[threadName][procName] = impl;
// We have split away the procedure calls for one thread.
procCopies[procName]--;
}
}
// Tell con that we're done with one thread.
con.nextThread();
}
// New re-route procedure calls as needed
// First async calls.
foreach (var impl in impls(originalProgram))
{
foreach (var blk in impl.Blocks)
{
for (int i = 0; i < blk.Cmds.Count; i++)
{
bpl.Cmd cmd = blk.Cmds[i];
if (con.isAsyncCall(cmd))
{
var callCmd = cmd as bpl.CallCmd;
var newCallCmd = new bpl.CallCmd(bpl.Token.NoToken, newProcsPerThread[callCmd.callee][callCmd.callee].Name, callCmd.Ins, callCmd.Outs, callCmd.Attributes, callCmd.IsAsync);
newCallCmd.TypeParameters = callCmd.TypeParameters;
newCallCmd.Proc = newProcsPerThread[callCmd.callee][callCmd.callee];
blk.Cmds[i] = newCallCmd;
}
}
}
}
// Now sync calls.
foreach (var elem in newImplsPerThread)
{
string threadName = elem.Key;
var newImpls = newImplsPerThread[threadName];
foreach (var implTuple in newImpls)
{
var impl = implTuple.Value;
foreach (var blk in impl.Blocks)
{
for (int i = 0; i < blk.Cmds.Count; ++i)
{
bpl.Cmd cmd = blk.Cmds[i];
if (con.isSyncCall(cmd) && newProcsPerThread[threadName].ContainsKey((cmd as bpl.CallCmd).callee))
{
var callCmd = cmd as bpl.CallCmd;
var newCallCmd = new bpl.CallCmd(bpl.Token.NoToken, newProcsPerThread[threadName][callCmd.callee].Name, callCmd.Ins, callCmd.Outs, callCmd.Attributes, callCmd.IsAsync);
newCallCmd.TypeParameters = callCmd.TypeParameters;
newCallCmd.Proc = newProcsPerThread[threadName][callCmd.callee];
blk.Cmds[i] = newCallCmd;
}
}
}
}
}
// Finally, label the entry of each thread as thread entry.
foreach (var elem in newProcsPerThread)
{
var proc = elem.Value[elem.Key];
var threadEntryAttr = con.getThreadEntryAttr();
threadEntryAttr.Next = proc.Attributes;
proc.Attributes = threadEntryAttr;
}
return(originalProgram);
}
private static GenKillWeight getWeight(Cmd cmd) {
Contract.Requires(cmd != null);
Contract.Ensures(Contract.Result<GenKillWeight>() != null);
return getWeight(cmd, null, null);
}
private static Bpl.IfCmd BuildIfCmd(Bpl.Expr b, Bpl.Cmd cmd, Bpl.IfCmd ifCmd)
{
Bpl.StmtListBuilder ifStmtBuilder = new Bpl.StmtListBuilder();
ifStmtBuilder.Add(cmd);
return(new Bpl.IfCmd(b.tok, b, ifStmtBuilder.Collect(b.tok), ifCmd, null));
}
void PredicateCmd(List<Block> blocks, Block block, Cmd cmd, out Block nextBlock)
{
if (!useProcedurePredicates && cmd is CallCmd) {
var trueBlock = new Block();
blocks.Add(trueBlock);
trueBlock.Label = block.Label + ".call.true";
trueBlock.Cmds.Add(new AssumeCmd(Token.NoToken, p));
trueBlock.Cmds.Add(cmd);
var falseBlock = new Block();
blocks.Add(falseBlock);
falseBlock.Label = block.Label + ".call.false";
falseBlock.Cmds.Add(new AssumeCmd(Token.NoToken, Expr.Not(p)));
var contBlock = new Block();
blocks.Add(contBlock);
contBlock.Label = block.Label + ".call.cont";
block.TransferCmd =
new GotoCmd(Token.NoToken, new List<Block> { trueBlock, falseBlock });
trueBlock.TransferCmd = falseBlock.TransferCmd =
new GotoCmd(Token.NoToken, new List<Block> { contBlock });
nextBlock = contBlock;
} else {
PredicateCmd(block.Cmds, cmd);
nextBlock = block;
}
}
bool ContainsReachVariable(Cmd c)
{
Contract.Requires(c != null);
AssertCmd artc = c as AssertCmd;
AssumeCmd amec = c as AssumeCmd;
Expr e;
if (artc != null) {
e = artc.Expr;
} else if (amec != null) {
e = amec.Expr;
} else {
return false;
}
Set freevars = new Set();
e.ComputeFreeVariables(freevars);
foreach (Variable v in freevars) {
Contract.Assert(v != null);
if (v.Name.Contains(reachvarsuffix))
return true;
}
return false;
}
public Parser(Scanner/*!*/ scanner, Errors/*!*/ errors, bool disambiguation)
: this(scanner, errors)
{
// initialize readonly fields
Pgm = new Program();
dummyExpr = new LiteralExpr(Token.NoToken, false);
dummyCmd = new AssumeCmd(Token.NoToken, dummyExpr);
dummyBlock = new Block(Token.NoToken, "dummyBlock", new List<Cmd>(), new ReturnCmd(Token.NoToken));
dummyType = new BasicType(Token.NoToken, SimpleType.Bool);
dummyExprSeq = new List<Expr> ();
dummyTransferCmd = new ReturnCmd(Token.NoToken);
dummyStructuredCmd = new BreakCmd(Token.NoToken, null);
}
void ParCallCmd(out Cmd d) {
Contract.Ensures(Contract.ValueAtReturn(out d) != null);
IToken x;
QKeyValue kv = null;
Cmd c = null;
List<CallCmd> callCmds = new List<CallCmd>();
Expect(54);
x = t;
while (la.kind == 28) {
Attribute(ref kv);
}
CallParams(false, false, kv, x, out c);
callCmds.Add((CallCmd)c);
while (la.kind == 55) {
Get();
CallParams(false, false, kv, x, out c);
callCmds.Add((CallCmd)c);
}
Expect(9);
d = new ParCallCmd(x, callCmds, kv);
}
void LabelOrAssign(out Cmd c, out IToken label) {
IToken/*!*/ id; IToken/*!*/ x, y; Expr/*!*/ e0;
c = dummyCmd; label = null;
AssignLhs/*!*/ lhs;
List<AssignLhs/*!*/>/*!*/ lhss;
List<Expr/*!*/>/*!*/ rhss;
List<Expr/*!*/>/*!*/ indexes;
Ident(out id);
x = t;
if (la.kind == 12) {
Get();
c = null; label = x;
} else if (la.kind == 13 || la.kind == 18 || la.kind == 51) {
lhss = new List<AssignLhs/*!*/>();
lhs = new SimpleAssignLhs(id, new IdentifierExpr(id, id.val));
while (la.kind == 18) {
MapAssignIndex(out y, out indexes);
lhs = new MapAssignLhs(y, lhs, indexes);
}
lhss.Add(lhs);
while (la.kind == 13) {
Get();
Ident(out id);
lhs = new SimpleAssignLhs(id, new IdentifierExpr(id, id.val));
while (la.kind == 18) {
MapAssignIndex(out y, out indexes);
lhs = new MapAssignLhs(y, lhs, indexes);
}
lhss.Add(lhs);
}
Expect(51);
x = t; /* use location of := */
Expression(out e0);
rhss = new List<Expr/*!*/> ();
rhss.Add(e0);
while (la.kind == 13) {
Get();
Expression(out e0);
rhss.Add(e0);
}
Expect(9);
c = new AssignCmd(x, lhss, rhss);
} else SynErr(111);
}
// perform in place update of liveSet
public static void Propagate(Cmd cmd, HashSet<Variable/*!*/>/*!*/ liveSet) {
Contract.Requires(cmd != null);
Contract.Requires(cce.NonNullElements(liveSet));
if (cmd is AssignCmd) {
AssignCmd/*!*/ assignCmd = (AssignCmd)cce.NonNull(cmd);
// I must first iterate over all the targets and remove the live ones.
// After the removals are done, I must add the variables referred on
// the right side of the removed targets
AssignCmd simpleAssignCmd = assignCmd.AsSimpleAssignCmd;
HashSet<int> indexSet = new HashSet<int>();
int index = 0;
foreach (AssignLhs/*!*/ lhs in simpleAssignCmd.Lhss) {
Contract.Assert(lhs != null);
SimpleAssignLhs salhs = lhs as SimpleAssignLhs;
Contract.Assert(salhs != null);
Variable var = salhs.DeepAssignedVariable;
if (var != null && liveSet.Contains(var)) {
indexSet.Add(index);
liveSet.Remove(var);
}
index++;
}
index = 0;
foreach (Expr/*!*/ expr in simpleAssignCmd.Rhss) {
Contract.Assert(expr != null);
if (indexSet.Contains(index)) {
VariableCollector/*!*/ collector = new VariableCollector();
collector.Visit(expr);
liveSet.UnionWith(collector.usedVars);
}
index++;
}
} else if (cmd is HavocCmd) {
HavocCmd/*!*/ havocCmd = (HavocCmd)cmd;
foreach (IdentifierExpr/*!*/ expr in havocCmd.Vars) {
Contract.Assert(expr != null);
if (expr.Decl != null && !(QKeyValue.FindBoolAttribute(expr.Decl.Attributes, "assumption") && expr.Decl.Name.StartsWith("a##cached##"))) {
liveSet.Remove(expr.Decl);
}
}
} else if (cmd is PredicateCmd) {
Contract.Assert((cmd is AssertCmd || cmd is AssumeCmd));
PredicateCmd/*!*/ predicateCmd = (PredicateCmd)cce.NonNull(cmd);
if (predicateCmd.Expr is LiteralExpr) {
LiteralExpr le = (LiteralExpr)predicateCmd.Expr;
if (le.IsFalse) {
liveSet.Clear();
}
} else {
VariableCollector/*!*/ collector = new VariableCollector();
collector.Visit(predicateCmd.Expr);
liveSet.UnionWith(collector.usedVars);
}
} else if (cmd is CommentCmd) {
// comments are just for debugging and don't affect verification
} else if (cmd is SugaredCmd) {
SugaredCmd/*!*/ sugCmd = (SugaredCmd)cce.NonNull(cmd);
Propagate(sugCmd.Desugaring, liveSet);
} else if (cmd is StateCmd) {
StateCmd/*!*/ stCmd = (StateCmd)cce.NonNull(cmd);
List<Cmd>/*!*/ cmds = cce.NonNull(stCmd.Cmds);
int len = cmds.Count;
for (int i = len - 1; i >= 0; i--) {
Propagate(cmds[i], liveSet);
}
foreach (Variable/*!*/ v in stCmd.Locals) {
Contract.Assert(v != null);
liveSet.Remove(v);
}
} else {
{
Contract.Assert(false);
throw new cce.UnreachableException();
}
}
}
private static GenKillWeight getWeightBeforeCall(Cmd cmd) {
Contract.Requires(cmd != null);
Contract.Ensures(Contract.Result<GenKillWeight>() != null);
Contract.Assert((cmd is CallCmd));
if (weightCacheBeforeCall.ContainsKey(cmd))
return weightCacheBeforeCall[cmd];
HashSet<Variable/*!*/>/*!*/ gen = new HashSet<Variable/*!*/>();
HashSet<Variable/*!*/>/*!*/ kill = new HashSet<Variable/*!*/>();
CallCmd/*!*/ ccmd = cce.NonNull((CallCmd/*!*/)cmd);
foreach (Expr/*!*/ expr in ccmd.Ins) {
Contract.Assert(expr != null);
VariableCollector/*!*/ collector = new VariableCollector();
collector.Visit(expr);
gen.UnionWith(collector.usedVars);
}
Contract.Assert(ccmd.Proc != null);
// Variables in requires are considered as "read"
foreach (Requires/*!*/ re in ccmd.Proc.Requires) {
Contract.Assert(re != null);
VariableCollector/*!*/ collector = new VariableCollector();
collector.Visit(re.Condition);
foreach (Variable/*!*/ v in collector.usedVars) {
Contract.Assert(v != null);
if (v is GlobalVariable) {
gen.Add(v);
}
}
}
// Old variables in ensures are considered as "read"
foreach (Ensures/*!*/ re in ccmd.Proc.Ensures) {
Contract.Assert(re != null);
VariableCollector/*!*/ collector = new VariableCollector();
collector.Visit(re.Condition);
foreach (Variable/*!*/ v in collector.oldVarsUsed) {
Contract.Assert(v != null);
if (v is GlobalVariable) {
gen.Add(v);
}
}
}
GenKillWeight/*!*/ ret = new GenKillWeight(gen, kill);
Contract.Assert(ret != null);
weightCacheAfterCall[cmd] = ret;
return ret;
}
private static GenKillWeight getWeightAfterCall(Cmd cmd) {
Contract.Requires(cmd != null);
Contract.Ensures(Contract.Result<GenKillWeight>() != null);
if (weightCacheAfterCall.ContainsKey(cmd))
return weightCacheAfterCall[cmd];
HashSet<Variable/*!*/>/*!*/ gen = new HashSet<Variable/*!*/>();
HashSet<Variable/*!*/>/*!*/ kill = new HashSet<Variable/*!*/>();
Contract.Assert(cmd is CallCmd);
CallCmd/*!*/ ccmd = cce.NonNull((CallCmd)cmd);
foreach (IdentifierExpr/*!*/ ie in ccmd.Outs) {
Contract.Assert(ie != null);
if (ie.Decl != null)
kill.Add(ie.Decl);
}
// Variables in ensures are considered as "read"
foreach (Ensures/*!*/ re in cce.NonNull(ccmd.Proc).Ensures) {
Contract.Assert(re != null);
VariableCollector/*!*/ collector = new VariableCollector();
collector.Visit(re.Condition);
foreach (Variable/*!*/ v in collector.usedVars) {
Contract.Assert(v != null);
if (v is GlobalVariable) {
gen.Add(v);
}
}
}
GenKillWeight/*!*/ ret = new GenKillWeight(gen, kill);
Contract.Assert(ret != null);
weightCacheAfterCall[cmd] = ret;
return ret;
}
private static GenKillWeight getWeight(Cmd cmd, Implementation impl, Program prog) {
Contract.Requires(cmd != null);
Contract.Ensures(Contract.Result<GenKillWeight>() != null);
if (weightCache.ContainsKey(cmd))
return weightCache[cmd];
HashSet<Variable/*!*/>/*!*/ gen = new HashSet<Variable/*!*/>();
HashSet<Variable/*!*/>/*!*/ kill = new HashSet<Variable/*!*/>();
GenKillWeight/*!*/ ret;
if (cmd is AssignCmd) {
AssignCmd/*!*/ assignCmd = (AssignCmd)cmd;
Contract.Assert(cmd != null);
// I must first iterate over all the targets and remove the live ones.
// After the removals are done, I must add the variables referred on
// the right side of the removed targets
foreach (AssignLhs/*!*/ lhs in assignCmd.Lhss) {
Contract.Assert(lhs != null);
Variable var = lhs.DeepAssignedVariable;
if (var != null) {
if (lhs is SimpleAssignLhs) {
// we should only remove non-map target variables because there is an implicit
// read of a map variable in an assignment to it
kill.Add(var);
}
}
}
int index = 0;
foreach (Expr/*!*/ expr in assignCmd.Rhss) {
Contract.Assert(expr != null);
VariableCollector/*!*/ collector = new VariableCollector();
collector.Visit(expr);
gen.UnionWith(collector.usedVars);
AssignLhs lhs = assignCmd.Lhss[index];
if (lhs is MapAssignLhs) {
// If the target is a map, then all indices are also read
MapAssignLhs malhs = (MapAssignLhs)lhs;
foreach (Expr e in malhs.Indexes) {
VariableCollector/*!*/ c = new VariableCollector();
c.Visit(e);
gen.UnionWith(c.usedVars);
}
}
index++;
}
ret = new GenKillWeight(gen, kill);
} else if (cmd is HavocCmd) {
HavocCmd/*!*/ havocCmd = (HavocCmd)cce.NonNull(cmd);
foreach (IdentifierExpr/*!*/ expr in havocCmd.Vars) {
Contract.Assert(expr != null);
if (expr.Decl != null) {
kill.Add(expr.Decl);
}
}
ret = new GenKillWeight(gen, kill);
} else if (cmd is PredicateCmd) {
Contract.Assert((cmd is AssertCmd || cmd is AssumeCmd));
PredicateCmd/*!*/ predicateCmd = (PredicateCmd)cce.NonNull(cmd);
if (predicateCmd.Expr is LiteralExpr && prog != null && impl != null) {
LiteralExpr le = (LiteralExpr)predicateCmd.Expr;
if (le.IsFalse) {
var globals = prog.GlobalVariables;
Contract.Assert(cce.NonNullElements(globals));
foreach (Variable/*!*/ v in globals) {
Contract.Assert(v != null);
kill.Add(v);
}
foreach (Variable/*!*/ v in impl.LocVars) {
Contract.Assert(v != null);
kill.Add(v);
}
foreach (Variable/*!*/ v in impl.OutParams) {
Contract.Assert(v != null);
kill.Add(v);
}
}
} else {
VariableCollector/*!*/ collector = new VariableCollector();
collector.Visit(predicateCmd.Expr);
gen.UnionWith(collector.usedVars);
}
ret = new GenKillWeight(gen, kill);
} else if (cmd is CommentCmd) {
ret = new GenKillWeight(gen, kill);
// comments are just for debugging and don't affect verification
} else if (cmd is SugaredCmd) {
SugaredCmd/*!*/ sugCmd = (SugaredCmd)cmd;
Contract.Assert(sugCmd != null);
ret = getWeight(sugCmd.Desugaring, impl, prog);
} else if (cmd is StateCmd) {
StateCmd/*!*/ stCmd = (StateCmd)cmd;
Contract.Assert(stCmd != null);
List<Cmd>/*!*/ cmds = stCmd.Cmds;
Contract.Assert(cmds != null);
int len = cmds.Count;
ret = GenKillWeight.one();
for (int i = len - 1; i >= 0; i--) {
GenKillWeight/*!*/ w = getWeight(cmds[i], impl, prog);
Contract.Assert(w != null);
ret = GenKillWeight.extend(w, ret);
}
foreach (Variable/*!*/ v in stCmd.Locals) {
Contract.Assert(v != null);
kill.Add(v);
}
ret = GenKillWeight.extend(new GenKillWeight(gen, kill), ret);
} else {
{
Contract.Assert(false);
throw new cce.UnreachableException();
}
}
weightCache[cmd] = ret;
return ret;
}
void CallCmd(out Cmd c) {
Contract.Ensures(Contract.ValueAtReturn(out c) != null);
IToken x;
bool isAsync = false;
bool isFree = false;
QKeyValue kv = null;
c = null;
if (la.kind == 52) {
Get();
isAsync = true;
}
if (la.kind == 36) {
Get();
isFree = true;
}
Expect(53);
x = t;
while (la.kind == 28) {
Attribute(ref kv);
}
CallParams(isAsync, isFree, kv, x, out c);
}
static List<Cmd> GetOptimizedBody(List<Cmd> cmds) {
Contract.Requires(cmds != null);
Contract.Ensures(Contract.Result<List<Cmd>>() != null);
int n = 0;
foreach (Cmd c in cmds) {
n++;
PredicateCmd pc = c as PredicateCmd;
if (pc != null && pc.Expr is LiteralExpr && ((LiteralExpr)pc.Expr).IsFalse) {
// return a sequence consisting of the commands seen so far
Cmd[] s = new Cmd[n];
for (int i = 0; i < n; i++) {
s[i] = cmds[i];
}
return new List<Cmd>(s);
}
}
return cmds;
}
void CallParams(bool isAsync, bool isFree, QKeyValue kv, IToken x, out Cmd c) {
List<IdentifierExpr> ids = new List<IdentifierExpr>();
List<Expr> es = new List<Expr>();
Expr en;
IToken first;
IToken p;
c = null;
Ident(out first);
if (la.kind == 10) {
Get();
if (StartOf(9)) {
Expression(out en);
es.Add(en);
while (la.kind == 13) {
Get();
Expression(out en);
es.Add(en);
}
}
Expect(11);
c = new CallCmd(x, first.val, es, ids, kv); ((CallCmd) c).IsFree = isFree; ((CallCmd) c).IsAsync = isAsync;
} else if (la.kind == 13 || la.kind == 51) {
ids.Add(new IdentifierExpr(first, first.val));
if (la.kind == 13) {
Get();
Ident(out p);
ids.Add(new IdentifierExpr(p, p.val));
while (la.kind == 13) {
Get();
Ident(out p);
ids.Add(new IdentifierExpr(p, p.val));
}
}
Expect(51);
Ident(out first);
Expect(10);
if (StartOf(9)) {
Expression(out en);
es.Add(en);
while (la.kind == 13) {
Get();
Expression(out en);
es.Add(en);
}
}
Expect(11);
c = new CallCmd(x, first.val, es, ids, kv); ((CallCmd) c).IsFree = isFree; ((CallCmd) c).IsAsync = isAsync;
} else SynErr(112);
}
/// <summary>
/// Computes the wlp for an assert or assume command "cmd".
/// </summary>
public static VCExpr P_Cmd(Block b, HashSet<string> constantsAssumed, Cmd cmd, VCExpr N, VCContext ctxt)
{
Contract.Requires(cmd != null);
Contract.Requires(N != null);
Contract.Requires(ctxt != null);
Contract.Ensures(Contract.Result<VCExpr>() != null);
VCExpressionGenerator gen = ctxt.Ctxt.ExprGen;
Contract.Assert(gen != null);
if (cmd is AssertCmd)
{
AssertCmd ac = (AssertCmd)cmd;
ctxt.Ctxt.BoogieExprTranslator.isPositiveContext = !ctxt.Ctxt.BoogieExprTranslator.isPositiveContext;
VCExpr C = ctxt.Ctxt.BoogieExprTranslator.Translate(ac.Expr);
ctxt.Ctxt.BoogieExprTranslator.isPositiveContext = !ctxt.Ctxt.BoogieExprTranslator.isPositiveContext;
if (CommandLineOptions.Clo.vcVariety == CommandLineOptions.VCVariety.Doomed)
{
return gen.Implies(C, N);
}
else
{
int id = ac.UniqueId;
if (ctxt.Label2absy != null)
{
ctxt.Label2absy[id] = ac;
}
switch (Subsumption(ac))
{
case CommandLineOptions.SubsumptionOption.Never:
break;
case CommandLineOptions.SubsumptionOption.Always:
N = gen.Implies(C, N);
break;
case CommandLineOptions.SubsumptionOption.NotForQuantifiers:
if (!(C is VCExprQuantifier))
{
N = gen.Implies(C, N);
}
break;
default:
Contract.Assert(false); throw new cce.UnreachableException(); // unexpected case
}
// (MSchaef) Hack: This line might be useless, but at least it is not harmful
// need to test it
if (CommandLineOptions.Clo.vcVariety == CommandLineOptions.VCVariety.Doomed)
return gen.Implies(C, N);
ctxt.AssertionCount++;
if (ctxt.ControlFlowVariableExpr == null)
{
Contract.Assert(ctxt.Label2absy != null);
return gen.AndSimp(gen.LabelNeg(cce.NonNull(id.ToString()), C), N);
}
else
{
VCExpr controlFlowFunctionAppl = gen.ControlFlowFunctionApplication(ctxt.ControlFlowVariableExpr, gen.Integer(BigNum.FromInt(b.UniqueId)));
Contract.Assert(controlFlowFunctionAppl != null);
VCExpr assertFailure = gen.Eq(controlFlowFunctionAppl, gen.Integer(BigNum.FromInt(-ac.UniqueId)));
if (ctxt.Label2absy == null)
{
return gen.AndSimp(gen.Implies(assertFailure, C), N);
}
else
{
return gen.AndSimp(gen.LabelNeg(cce.NonNull(id.ToString()), gen.Implies(assertFailure, C)), N);
}
}
}
}
else if (cmd is AssumeCmd)
{
AssumeCmd ac = (AssumeCmd)cmd;
if (CommandLineOptions.Clo.StratifiedInlining > 0)
{
Contract.Assert(false);
throw new System.Exception(string.Format("VC Generation in ICE-learning does not handle stratified inlining"));
var pname = QKeyValue.FindStringAttribute(ac.Attributes, "candidate");
if (pname != null)
{
return gen.ImpliesSimp(gen.LabelPos("candidate_" + pname.ToString(), ctxt.Ctxt.BoogieExprTranslator.Translate(ac.Expr)), N);
}
// Label the assume if it is a procedure call
NAryExpr naryExpr = ac.Expr as NAryExpr;
if (naryExpr != null)
{
if (naryExpr.Fun is FunctionCall)
{
int id = ac.UniqueId;
ctxt.Label2absy[id] = ac;
return gen.ImpliesSimp(gen.LabelPos(cce.NonNull("si_fcall_" + id.ToString()), ctxt.Ctxt.BoogieExprTranslator.Translate(ac.Expr)), N);
}
}
}
else
{
if (constantsAssumed == null)
return gen.ImpliesSimp(ctxt.Ctxt.BoogieExprTranslator.Translate(ac.Expr), N);
// check if the assume command contains any of the constantsAssumed (corresponding to existential function calls)?
var funcsUsed = FunctionCollector.Collect(ac.Expr);
bool hasAnyConstantAssumed = false;
foreach (var tup in funcsUsed)
{
var constantFunc = tup.Item1;
if (constantsAssumed.Contains(constantFunc.Name))
{
hasAnyConstantAssumed = true;
break;
}
}
if (hasAnyConstantAssumed)
{
int id = ac.UniqueId;
if (ctxt.Label2absy != null)
{
ctxt.Label2absy[id] = ac;
}
//ctxt.AssertionCount++;
if (ctxt.ControlFlowVariableExpr == null)
{
Contract.Assert(ctxt.Label2absy != null);
return gen.ImpliesSimp(gen.LabelPos(cce.NonNull(id.ToString()), ctxt.Ctxt.BoogieExprTranslator.Translate(ac.Expr)), N);
}
else
{
/* TODO: Check if this is correct!! */
VCExpr controlFlowFunctionAppl = gen.ControlFlowFunctionApplication(ctxt.ControlFlowVariableExpr, gen.Integer(BigNum.FromInt(b.UniqueId)));
Contract.Assert(controlFlowFunctionAppl != null);
VCExpr assumeFailure = gen.Eq(controlFlowFunctionAppl, gen.Integer(BigNum.FromInt(-ac.UniqueId)));
if (ctxt.Label2absy == null)
{
throw new System.Exception(string.Format("Dont know how to handle labels for the assume cmd"));
//return gen.ImpliesSimp(gen.LabelPos(cce.NonNull(id.ToString()), gen.Implies(assumeFailure, ctxt.Ctxt.BoogieExprTranslator.Translate(ac.Expr))), N);
}
else
{
return gen.ImpliesSimp(gen.LabelPos(cce.NonNull(id.ToString()), gen.Implies(assumeFailure, ctxt.Ctxt.BoogieExprTranslator.Translate(ac.Expr))), N);
}
}
}
else return gen.ImpliesSimp(ctxt.Ctxt.BoogieExprTranslator.Translate(ac.Expr), N);
}
}
else
{
Console.WriteLine(cmd.ToString());
Contract.Assert(false); throw new cce.UnreachableException(); // unexpected command
}
}
void LabelOrCmd(out Cmd c, out IToken label) {
IToken/*!*/ x; Expr/*!*/ e;
List<IToken>/*!*/ xs;
List<IdentifierExpr> ids;
c = dummyCmd; label = null;
Cmd/*!*/ cn;
QKeyValue kv = null;
switch (la.kind) {
case 1: {
LabelOrAssign(out c, out label);
break;
}
case 47: {
Get();
x = t;
while (la.kind == 28) {
Attribute(ref kv);
}
Proposition(out e);
c = new AssertCmd(x, e, kv);
Expect(9);
break;
}
case 48: {
Get();
x = t;
while (la.kind == 28) {
Attribute(ref kv);
}
Proposition(out e);
c = new AssumeCmd(x, e, kv);
Expect(9);
break;
}
case 49: {
Get();
x = t;
Idents(out xs);
Expect(9);
ids = new List<IdentifierExpr>();
foreach(IToken/*!*/ y in xs){
Contract.Assert(y != null);
ids.Add(new IdentifierExpr(y, y.val));
}
c = new HavocCmd(x,ids);
break;
}
case 36: case 52: case 53: {
CallCmd(out cn);
Expect(9);
c = cn;
break;
}
case 54: {
ParCallCmd(out cn);
c = cn;
break;
}
case 50: {
Get();
x = t;
Expect(9);
c = new YieldCmd(x);
break;
}
default: SynErr(106); break;
}
}
// ----------------------------- Substitutions for Cmd -------------------------------
/// <summary>
/// Apply a substitution to a command. Any variables not in domain(subst)
/// is not changed. The substitutions apply within the "old", but the "old"
/// expression remains.
/// </summary>
public static Cmd Apply(Substitution subst, Cmd cmd) {
Contract.Requires(subst != null);
Contract.Requires(cmd != null);
Contract.Ensures(Contract.Result<Cmd>() != null);
return (Cmd)new NormalSubstituter(subst).Visit(cmd);
}
private void GenerateErrorMessage(Cmd causalStatement, List<Cmd> causals)
{
Contract.Requires(causalStatement != null);
Contract.Requires(cce.NonNullElements(causals));
AssumeCmd uc = causalStatement as AssumeCmd;
AssertCmd ac = causalStatement as AssertCmd;
ConsoleColor col = Console.ForegroundColor;
// Trivial case. Must be either assume or assert false
if (m_doomedCmds.Count == 1) {
Console.WriteLine("Found a trivial error:");
if (uc != null) {
Console.Write("Trivial false assumption: ");
Console.Write("({0};{1}):", uc.tok.line, uc.tok.col);
}
if (ac != null) {
Console.Write("Trivial false assertion: ");
Console.Write("({0};{1}):", ac.tok.line, ac.tok.col);
}
causalStatement.Emit(new TokenTextWriter("<console>", Console.Out, false), 0);
} else {
// Safety error
if (ac != null) {
Console.ForegroundColor = ConsoleColor.Red;
Console.WriteLine("Safety error:");
Console.ForegroundColor = col;
Console.Write("This assertion is violated: ");
Console.Write("({0};{1}):", ac.tok.line, ac.tok.col);
ac.Emit(new TokenTextWriter("<console>", Console.Out, false), 0);
}
if (uc != null) {
bool containsAssert = false;
foreach (Cmd c in m_doomedCmds) {
Contract.Assert(c != null);
if (causals.Contains(c)) {
continue;
}
AssertCmd asrt = c as AssertCmd;
if (asrt != null) {
containsAssert = true;
break;
}
}
// Plausibility error
if (containsAssert) {
Console.ForegroundColor = ConsoleColor.Yellow;
Console.WriteLine("Plausibility error:");
Console.ForegroundColor = col;
Console.Write("There is no legal exeuction passing: ");
Console.Write("({0};{1})", uc.tok.line, uc.tok.col);
uc.Emit(new TokenTextWriter("<console>", Console.Out, false), 0);
} else { // Reachability error
Console.ForegroundColor = ConsoleColor.DarkRed;
Console.WriteLine("Reachability error:");
Console.ForegroundColor = col;
Console.Write("No execution can reach: ");
Console.Write("({0};{1})", uc.tok.line, uc.tok.col);
uc.Emit(new TokenTextWriter("<console>", Console.Out, false), 0);
}
}
Console.ForegroundColor = ConsoleColor.White;
Console.WriteLine("...on any execution passing through:");
foreach (Cmd c in m_doomedCmds) {
Contract.Assert(c != null);
if (causals.Contains(c)) {
continue;
}
Console.ForegroundColor = col;
Console.Write("In ({0};{1}): ", c.tok.line, c.tok.col);
Console.ForegroundColor = ConsoleColor.DarkYellow;
c.Emit(new TokenTextWriter("<console>", Console.Out, false), 0);
}
Console.ForegroundColor = col;
Console.WriteLine("--");
}
}
/// <summary>
/// Computes the wlp for an assert or assume command "cmd".
/// </summary>
public static VCExpr Cmd(Block b, Cmd cmd, VCExpr N, VCContext ctxt)
{
Contract.Requires(cmd != null);
Contract.Requires(N != null);
Contract.Requires(ctxt != null);
Contract.Ensures(Contract.Result<VCExpr>() != null);
VCExpressionGenerator gen = ctxt.Ctxt.ExprGen;
Contract.Assert(gen != null);
if (cmd is AssertCmd) {
AssertCmd ac = (AssertCmd)cmd;
ctxt.Ctxt.BoogieExprTranslator.isPositiveContext = !ctxt.Ctxt.BoogieExprTranslator.isPositiveContext;
VCExpr C = ctxt.Ctxt.BoogieExprTranslator.Translate(ac.Expr);
ctxt.Ctxt.BoogieExprTranslator.isPositiveContext = !ctxt.Ctxt.BoogieExprTranslator.isPositiveContext;
if (CommandLineOptions.Clo.vcVariety == CommandLineOptions.VCVariety.Doomed) {
return gen.Implies(C, N);
} else {
int id = ac.UniqueId;
if (ctxt.Label2absy != null) {
ctxt.Label2absy[id] = ac;
}
switch (Subsumption(ac)) {
case CommandLineOptions.SubsumptionOption.Never:
break;
case CommandLineOptions.SubsumptionOption.Always:
N = gen.Implies(C, N);
break;
case CommandLineOptions.SubsumptionOption.NotForQuantifiers:
if (!(C is VCExprQuantifier)) {
N = gen.Implies(C, N);
}
break;
default:
Contract.Assert(false); throw new cce.UnreachableException(); // unexpected case
}
// (MSchaef) Hack: This line might be useless, but at least it is not harmful
// need to test it
if (CommandLineOptions.Clo.vcVariety == CommandLineOptions.VCVariety.Doomed)
return gen.Implies(C, N);
ctxt.AssertionCount++;
if (ctxt.ControlFlowVariableExpr == null) {
Contract.Assert(ctxt.Label2absy != null);
return gen.AndSimp(gen.LabelNeg(cce.NonNull(id.ToString()), C), N);
} else {
VCExpr controlFlowFunctionAppl = gen.ControlFlowFunctionApplication(ctxt.ControlFlowVariableExpr, gen.Integer(BigNum.FromInt(b.UniqueId)));
Contract.Assert(controlFlowFunctionAppl != null);
VCExpr assertFailure = gen.Eq(controlFlowFunctionAppl, gen.Integer(BigNum.FromInt(-ac.UniqueId)));
if (ctxt.Label2absy == null) {
return gen.AndSimp(gen.Implies(assertFailure, C), N);
} else {
return gen.AndSimp(gen.LabelNeg(cce.NonNull(id.ToString()), gen.Implies(assertFailure, C)), N);
}
}
}
} else if (cmd is AssumeCmd) {
AssumeCmd ac = (AssumeCmd)cmd;
if (CommandLineOptions.Clo.StratifiedInlining > 0) {
var pname = QKeyValue.FindStringAttribute(ac.Attributes, "candidate");
if (pname != null) {
return gen.ImpliesSimp(gen.LabelPos("candidate_" + pname.ToString(), ctxt.Ctxt.BoogieExprTranslator.Translate(ac.Expr)), N);
}
// Label the assume if it is a procedure call
NAryExpr naryExpr = ac.Expr as NAryExpr;
if (naryExpr != null) {
if (naryExpr.Fun is FunctionCall) {
int id = ac.UniqueId;
ctxt.Label2absy[id] = ac;
return gen.ImpliesSimp(gen.LabelPos(cce.NonNull("si_fcall_" + id.ToString()), ctxt.Ctxt.BoogieExprTranslator.Translate(ac.Expr)), N);
}
}
}
return gen.ImpliesSimp(ctxt.Ctxt.BoogieExprTranslator.Translate(ac.Expr), N);
} else {
Console.WriteLine(cmd.ToString());
Contract.Assert(false); throw new cce.UnreachableException(); // unexpected command
}
}
void PredicateCmd(List<Cmd> cmdSeq, Cmd cmd)
{
if (cmd is AssignCmd) {
var aCmd = (AssignCmd)cmd;
cmdSeq.Add(new AssignCmd(Token.NoToken, aCmd.Lhss,
new List<Expr>(aCmd.Lhss.Zip(aCmd.Rhss, (lhs, rhs) =>
new NAryExpr(Token.NoToken,
new IfThenElse(Token.NoToken),
new List<Expr> { p, rhs, lhs.AsExpr })))));
} else if (cmd is AssertCmd) {
var aCmd = (AssertCmd)cmd;
if (cmdSeq.Last() is AssignCmd &&
cmdSeq.Cast<Cmd>().SkipEnd(1).All(c => c is AssertCmd)) {
// This may be a loop invariant. Make sure it continues to appear as
// the first statement in the block.
var assign = cmdSeq.Last();
cmdSeq.RemoveAt(cmdSeq.Count-1);
Expr newExpr = new EnabledReplacementVisitor(pExpr).VisitExpr(aCmd.Expr);
aCmd.Expr = QKeyValue.FindBoolAttribute(aCmd.Attributes, "do_not_predicate") ? newExpr : Expr.Imp(pExpr, newExpr);
cmdSeq.Add(aCmd);
// cmdSeq.Add(new AssertCmd(aCmd.tok, Expr.Imp(pExpr, aCmd.Expr)));
cmdSeq.Add(assign);
} else {
aCmd.Expr = Expr.Imp(p, aCmd.Expr);
cmdSeq.Add(aCmd);
// cmdSeq.Add(new AssertCmd(aCmd.tok, Expr.Imp(p, aCmd.Expr)));
}
} else if (cmd is AssumeCmd) {
var aCmd = (AssumeCmd)cmd;
cmdSeq.Add(new AssumeCmd(Token.NoToken, Expr.Imp(p, aCmd.Expr)));
} else if (cmd is HavocCmd) {
var hCmd = (HavocCmd)cmd;
foreach (IdentifierExpr v in hCmd.Vars) {
Microsoft.Boogie.Type type = v.Decl.TypedIdent.Type;
Contract.Assert(type != null);
IdentifierExpr havocTempExpr;
if (havocVars.ContainsKey(type)) {
havocTempExpr = havocVars[type];
} else {
var havocVar = new LocalVariable(Token.NoToken,
new TypedIdent(Token.NoToken,
"_HAVOC_" + type.ToString(), type));
impl.LocVars.Add(havocVar);
havocVars[type] = havocTempExpr =
new IdentifierExpr(Token.NoToken, havocVar);
}
cmdSeq.Add(new HavocCmd(Token.NoToken,
new List<IdentifierExpr> { havocTempExpr }));
cmdSeq.Add(Cmd.SimpleAssign(Token.NoToken, v,
new NAryExpr(Token.NoToken,
new IfThenElse(Token.NoToken),
new List<Expr> { p, havocTempExpr, v })));
}
} else if (cmd is CallCmd) {
Debug.Assert(useProcedurePredicates);
var cCmd = (CallCmd)cmd;
cCmd.Ins.Insert(0, p);
cmdSeq.Add(cCmd);
}
else if (cmd is CommentCmd) {
// skip
}
else if (cmd is StateCmd) {
var sCmd = (StateCmd)cmd;
var newCmdSeq = new List<Cmd>();
foreach (Cmd c in sCmd.Cmds)
PredicateCmd(newCmdSeq, c);
sCmd.Cmds = newCmdSeq;
cmdSeq.Add(sCmd);
}
else {
Console.WriteLine("Unsupported cmd: " + cmd.GetType().ToString());
}
}
public void Add(Cmd cmd)
{
Contract.Requires(cmd != null);
if (simpleCmds == null) {
simpleCmds = new List<Cmd>();
}
simpleCmds.Add(cmd);
}
private bool IsCallCmdExitPoint(Cmd cmd, int yTypeCheckCurrentPhaseNum)
{
if (cmd is CallCmd)
{
CallCmd callee = cmd as CallCmd;
int phaseSpecCallee = moverTypeChecker.FindPhaseNumber(callee.Proc);
if (phaseSpecCallee >= yTypeCheckCurrentPhaseNum)
{
#if DEBUG && !DEBUG_DETAIL
Console.Write("\nCall Cmd Check is " + callCmd.Proc.Name + "\n");
#endif
return true;
}
}
return false;
}
/*
* Visitor functions of basic commands
*/
private string GetEdgeType(Cmd cmd)
{
if (cmd is YieldCmd)
{
return "Y";
}
else if (cmd is HavocCmd)
{
return "Q";
}
else if (cmd is AssumeCmd)
{
return "P";
}
else if (cmd is AssertCmd)
{
return "E";
}
else if (cmd is CallCmd)
{
CallCmd callCmd = cmd as CallCmd;
foreach (Ensures e in callCmd.Proc.Ensures)
{
if (QKeyValue.FindBoolAttribute(e.Attributes, "atomic"))
{
return "A";
}
else if (QKeyValue.FindBoolAttribute(e.Attributes, "right"))
{
return "R";
}
else if (QKeyValue.FindBoolAttribute(e.Attributes, "left"))
{
return "L";
}
else if (QKeyValue.FindBoolAttribute(e.Attributes, "both"))
{
return "B";
}
}
}
//rest can only be assigncmd
AssignCmd assgnCmd = cmd as AssignCmd;
return "Q";
}
void PredicateCmd(Expr p, Expr pDom, List<Cmd> cmdSeq, Cmd cmd) {
if (cmd is CallCmd) {
var cCmd = (CallCmd)cmd;
Debug.Assert(useProcedurePredicates(cCmd.Proc));
cCmd.Ins.Insert(0, p != null ? p : Expr.True);
cmdSeq.Add(cCmd);
} else if (p == null) {
new EnabledReplacementVisitor(Expr.True, pDom).Visit(cmd);
cmdSeq.Add(cmd);
} else if (cmd is AssignCmd) {
var aCmd = (AssignCmd)cmd;
cmdSeq.Add(new AssignCmd(Token.NoToken, aCmd.Lhss,
new List<Expr>(aCmd.Lhss.Zip(aCmd.Rhss, (lhs, rhs) =>
new NAryExpr(Token.NoToken,
new IfThenElse(Token.NoToken),
new List<Expr> { p, rhs, lhs.AsExpr })))));
} else if (cmd is AssertCmd) {
var aCmd = (AssertCmd)cmd;
Expr newExpr = new EnabledReplacementVisitor(p, pDom).VisitExpr(aCmd.Expr);
aCmd.Expr = QKeyValue.FindBoolAttribute(aCmd.Attributes, "do_not_predicate") ? newExpr : Expr.Imp(p, newExpr);
cmdSeq.Add(aCmd);
} else if (cmd is AssumeCmd) {
var aCmd = (AssumeCmd)cmd;
Expr newExpr = new EnabledReplacementVisitor(p, pDom).VisitExpr(aCmd.Expr);
aCmd.Expr = QKeyValue.FindBoolAttribute(aCmd.Attributes, "do_not_predicate") ? newExpr : Expr.Imp(p, newExpr);
cmdSeq.Add(aCmd);
} else if (cmd is HavocCmd) {
var hCmd = (HavocCmd)cmd;
foreach (IdentifierExpr v in hCmd.Vars) {
Microsoft.Boogie.Type type = v.Decl.TypedIdent.Type;
Contract.Assert(type != null);
IdentifierExpr havocTempExpr;
if (havocVars.ContainsKey(type)) {
havocTempExpr = havocVars[type];
} else {
var havocVar = new LocalVariable(Token.NoToken,
new TypedIdent(Token.NoToken,
"_HAVOC_" + type.ToString(), type));
impl.LocVars.Add(havocVar);
havocVars[type] = havocTempExpr =
new IdentifierExpr(Token.NoToken, havocVar);
}
cmdSeq.Add(new HavocCmd(Token.NoToken,
new List<IdentifierExpr> { havocTempExpr }));
cmdSeq.Add(Cmd.SimpleAssign(Token.NoToken, v,
new NAryExpr(Token.NoToken,
new IfThenElse(Token.NoToken),
new List<Expr> { p, havocTempExpr, v })));
}
} else if (cmd is CommentCmd) {
// skip
} else if (cmd is StateCmd) {
var sCmd = (StateCmd)cmd;
var newCmdSeq = new List<Cmd>();
foreach (Cmd c in sCmd.Cmds)
PredicateCmd(p, pDom, newCmdSeq, c);
sCmd.Cmds = newCmdSeq;
cmdSeq.Add(sCmd);
} else {
Console.WriteLine("Unsupported cmd: " + cmd.GetType().ToString());
}
}
/// <summary>
/// Computes the wlp for an assert or assume command "cmd".
/// </summary>
internal static VCExpr Cmd(Block b, Cmd cmd, VCExpr N, VCContext ctxt) {
Contract.Requires(cmd != null);
Contract.Requires(N != null);
Contract.Requires(ctxt != null);
Contract.Ensures(Contract.Result<VCExpr>() != null);
VCExpressionGenerator gen = ctxt.Ctxt.ExprGen;
Contract.Assert(gen != null);
if (cmd is AssertCmd) {
AssertCmd ac = (AssertCmd)cmd;
var isFullyVerified = false;
if (ac.VerifiedUnder != null)
{
var litExpr = ac.VerifiedUnder as LiteralExpr;
isFullyVerified = litExpr != null && litExpr.IsTrue;
}
if (!isFullyVerified)
{
ctxt.Ctxt.BoogieExprTranslator.isPositiveContext = !ctxt.Ctxt.BoogieExprTranslator.isPositiveContext;
}
VCExpr C = ctxt.Ctxt.BoogieExprTranslator.Translate(ac.Expr);
VCExpr VU = null;
if (!isFullyVerified)
{
if (ac.VerifiedUnder != null)
{
VU = ctxt.Ctxt.BoogieExprTranslator.Translate(ac.VerifiedUnder);
if (CommandLineOptions.Clo.RunDiagnosticsOnTimeout)
{
ctxt.Ctxt.TimeoutDiagnosticIDToAssertion[ctxt.Ctxt.TimoutDiagnosticsCount] = new Tuple<AssertCmd,TransferCmd>(ac, b.TransferCmd);
VU = gen.Or(VU, gen.Function(VCExpressionGenerator.TimeoutDiagnosticsOp, gen.Integer(BigNum.FromInt(ctxt.Ctxt.TimoutDiagnosticsCount++))));
}
}
else if (CommandLineOptions.Clo.RunDiagnosticsOnTimeout)
{
ctxt.Ctxt.TimeoutDiagnosticIDToAssertion[ctxt.Ctxt.TimoutDiagnosticsCount] = new Tuple<AssertCmd,TransferCmd>(ac, b.TransferCmd);
VU = gen.Function(VCExpressionGenerator.TimeoutDiagnosticsOp, gen.Integer(BigNum.FromInt(ctxt.Ctxt.TimoutDiagnosticsCount++)));
}
ctxt.Ctxt.BoogieExprTranslator.isPositiveContext = !ctxt.Ctxt.BoogieExprTranslator.isPositiveContext;
}
VCExpr R = null;
if (CommandLineOptions.Clo.vcVariety == CommandLineOptions.VCVariety.Doomed) {
R = gen.Implies(C, N);
} else {
var subsumption = Subsumption(ac);
if (subsumption == CommandLineOptions.SubsumptionOption.Always
|| (subsumption == CommandLineOptions.SubsumptionOption.NotForQuantifiers && !(C is VCExprQuantifier)))
{
N = gen.ImpliesSimp(C, N, false);
}
if (isFullyVerified)
{
return N;
}
else if (VU != null)
{
C = gen.OrSimp(VU, C);
}
int id = ac.UniqueId;
if (ctxt.Label2absy != null)
{
ctxt.Label2absy[id] = ac;
}
ctxt.AssertionCount++;
if (ctxt.ControlFlowVariableExpr == null) {
Contract.Assert(ctxt.Label2absy != null);
R = gen.AndSimp(gen.LabelNeg(cce.NonNull(id.ToString()), C), N);
} else {
VCExpr controlFlowFunctionAppl = gen.ControlFlowFunctionApplication(ctxt.ControlFlowVariableExpr, gen.Integer(BigNum.FromInt(b.UniqueId)));
Contract.Assert(controlFlowFunctionAppl != null);
VCExpr assertFailure = gen.Eq(controlFlowFunctionAppl, gen.Integer(BigNum.FromInt(-ac.UniqueId)));
if (ctxt.Label2absy == null) {
R = gen.AndSimp(gen.Implies(assertFailure, C), N);
} else {
R = gen.AndSimp(gen.LabelNeg(cce.NonNull(id.ToString()), gen.Implies(assertFailure, C)), N);
}
}
}
return R;
} else if (cmd is AssumeCmd) {
AssumeCmd ac = (AssumeCmd)cmd;
if (CommandLineOptions.Clo.StratifiedInlining > 0) {
// Label the assume if it is a procedure call
NAryExpr naryExpr = ac.Expr as NAryExpr;
if (naryExpr != null) {
if (naryExpr.Fun is FunctionCall) {
int id = ac.UniqueId;
ctxt.Label2absy[id] = ac;
return MaybeWrapWithOptimization(ctxt, gen, ac.Attributes, gen.ImpliesSimp(gen.LabelPos(cce.NonNull("si_fcall_" + id.ToString()), ctxt.Ctxt.BoogieExprTranslator.Translate(ac.Expr)), N));
}
}
}
var expr = ctxt.Ctxt.BoogieExprTranslator.Translate(ac.Expr);
var aid = QKeyValue.FindStringAttribute(ac.Attributes, "id");
if (aid != null)
{
var isTry = QKeyValue.FindBoolAttribute(ac.Attributes, "try");
var v = gen.Variable((isTry ? "try$$" : "assume$$") + aid, Microsoft.Boogie.Type.Bool);
expr = gen.Function(VCExpressionGenerator.NamedAssumeOp, v, gen.ImpliesSimp(v, expr));
}
var soft = QKeyValue.FindBoolAttribute(ac.Attributes, "soft");
var softWeight = QKeyValue.FindIntAttribute(ac.Attributes, "soft", 0);
if ((soft || 0 < softWeight) && aid != null)
{
var v = gen.Variable("soft$$" + aid, Microsoft.Boogie.Type.Bool);
expr = gen.Function(new VCExprSoftOp(Math.Max(softWeight, 1)), v, gen.ImpliesSimp(v, expr));
}
return MaybeWrapWithOptimization(ctxt, gen, ac.Attributes, gen.ImpliesSimp(expr, N));
} else {
Console.WriteLine(cmd.ToString());
Contract.Assert(false); throw new cce.UnreachableException(); // unexpected command
}
}
/// <summary>
/// Apply a substitution to a command replacing "old" expressions.
/// Outside "old" expressions, the substitution "always" is applied; any variable not in
/// domain(always) is not changed. Inside "old" expressions, apply map "forOld" to
/// variables in domain(forOld), apply map "always" to variables in
/// domain(always)-domain(forOld), and leave variable unchanged otherwise.
/// </summary>
public static Cmd ApplyReplacingOldExprs(Substitution always, Substitution forOld, Cmd cmd) {
Contract.Requires(always != null);
Contract.Requires(forOld != null);
Contract.Requires(cmd != null);
Contract.Ensures(Contract.Result<Cmd>() != null);
return (Cmd)new ReplacingOldSubstituter(always, forOld).Visit(cmd);
}
/// <summary>
/// Computes the wlp for an assert or assume command "cmd".
/// </summary>
public static VCExpr Cmd(Block b, Cmd cmd, VCExpr N, VCContext ctxt)
{
Contract.Requires(cmd != null);
Contract.Requires(N != null);
Contract.Requires(ctxt != null);
Contract.Ensures(Contract.Result<VCExpr>() != null);
VCExpressionGenerator gen = ctxt.Ctxt.ExprGen;
Contract.Assert(gen != null);
if (cmd is AssertCmd) {
AssertCmd ac = (AssertCmd)cmd;
var isFullyVerified = false;
if (ac.VerifiedUnder != null)
{
var litExpr = ac.VerifiedUnder as LiteralExpr;
isFullyVerified = litExpr != null && litExpr.IsTrue;
}
if (!isFullyVerified)
{
ctxt.Ctxt.BoogieExprTranslator.isPositiveContext = !ctxt.Ctxt.BoogieExprTranslator.isPositiveContext;
}
VCExpr C = ctxt.Ctxt.BoogieExprTranslator.Translate(ac.Expr);
VCExpr VU = null;
if (!isFullyVerified)
{
if (ac.VerifiedUnder != null)
{
VU = ctxt.Ctxt.BoogieExprTranslator.Translate(ac.VerifiedUnder);
if (CommandLineOptions.Clo.RunDiagnosticsOnTimeout)
{
ctxt.Ctxt.TimeoutDiagnosticIDToAssertion[ctxt.Ctxt.TimoutDiagnosticsCount] = new Tuple<AssertCmd,TransferCmd>(ac, b.TransferCmd);
VU = gen.Or(VU, gen.Function(VCExpressionGenerator.TimeoutDiagnosticsOp, gen.Integer(BigNum.FromInt(ctxt.Ctxt.TimoutDiagnosticsCount++))));
}
}
else if (CommandLineOptions.Clo.RunDiagnosticsOnTimeout)
{
ctxt.Ctxt.TimeoutDiagnosticIDToAssertion[ctxt.Ctxt.TimoutDiagnosticsCount] = new Tuple<AssertCmd,TransferCmd>(ac, b.TransferCmd);
VU = gen.Function(VCExpressionGenerator.TimeoutDiagnosticsOp, gen.Integer(BigNum.FromInt(ctxt.Ctxt.TimoutDiagnosticsCount++)));
}
ctxt.Ctxt.BoogieExprTranslator.isPositiveContext = !ctxt.Ctxt.BoogieExprTranslator.isPositiveContext;
}
VCExpr R = null;
if (CommandLineOptions.Clo.vcVariety == CommandLineOptions.VCVariety.Doomed) {
R = gen.Implies(C, N);
} else {
var subsumption = Subsumption(ac);
if (subsumption == CommandLineOptions.SubsumptionOption.Always
|| (subsumption == CommandLineOptions.SubsumptionOption.NotForQuantifiers && !(C is VCExprQuantifier)))
{
N = gen.ImpliesSimp(C, N, false);
}
if (isFullyVerified)
{
return N;
}
else if (VU != null)
{
C = gen.OrSimp(VU, C);
}
int id = ac.UniqueId;
if (ctxt.Label2absy != null)
{
ctxt.Label2absy[id] = ac;
}
ctxt.AssertionCount++;
if (ctxt.ControlFlowVariableExpr == null) {
Contract.Assert(ctxt.Label2absy != null);
R = gen.AndSimp(gen.LabelNeg(cce.NonNull(id.ToString()), C), N);
} else {
VCExpr controlFlowFunctionAppl = gen.ControlFlowFunctionApplication(ctxt.ControlFlowVariableExpr, gen.Integer(BigNum.FromInt(b.UniqueId)));
Contract.Assert(controlFlowFunctionAppl != null);
VCExpr assertFailure = gen.Eq(controlFlowFunctionAppl, gen.Integer(BigNum.FromInt(-ac.UniqueId)));
if (ctxt.Label2absy == null) {
R = gen.AndSimp(gen.Implies(assertFailure, C), N);
} else {
R = gen.AndSimp(gen.LabelNeg(cce.NonNull(id.ToString()), gen.Implies(assertFailure, C)), N);
}
}
}
return R;
} else if (cmd is AssumeCmd) {
AssumeCmd ac = (AssumeCmd)cmd;
if (CommandLineOptions.Clo.StratifiedInlining > 0) {
// Label the assume if it is a procedure call
NAryExpr naryExpr = ac.Expr as NAryExpr;
if (naryExpr != null) {
if (naryExpr.Fun is FunctionCall) {
int id = ac.UniqueId;
ctxt.Label2absy[id] = ac;
return gen.ImpliesSimp(gen.LabelPos(cce.NonNull("si_fcall_" + id.ToString()), ctxt.Ctxt.BoogieExprTranslator.Translate(ac.Expr)), N);
}
}
}
return gen.ImpliesSimp(ctxt.Ctxt.BoogieExprTranslator.Translate(ac.Expr), N);
} else {
Console.WriteLine(cmd.ToString());
Contract.Assert(false); throw new cce.UnreachableException(); // unexpected command
}
}
