private void CreateUsesChannel(VariableInformation vi, int useCount, VariableToChannelInformation vtci, IList <IStatement> stmts)
{
vtci.usageChannel = ChannelInfo.UseChannel(vi);
vtci.usageChannel.decl = vi.DeriveArrayVariable(stmts, context, vi.Name + "_uses", Builder.LiteralExpr(useCount), Builder.VarDecl("_ind", typeof(int)), useLiteralIndices: true);
context.InputAttributes.CopyObjectAttributesTo <InitialiseTo>(vi.declaration, context.OutputAttributes, vtci.usageChannel.decl);
context.OutputAttributes.Set(vtci.usageChannel.decl, vtci.usageChannel);
context.OutputAttributes.Set(vtci.usageChannel.decl, new DescriptionAttribute("uses of '" + vi.Name + "'"));
}
private void CreateUseChannel(IVariableDeclaration ivd, VariableInformation vi, IList <IStatement> stmts)
{
IVariableDeclaration useDecl = vi.DeriveIndexedVariable(stmts, context, ivd.Name + "_use");
useOfVariable[ivd] = useDecl;
ChannelInfo usageChannel = ChannelInfo.UseChannel(vi);
usageChannel.decl = useDecl;
context.InputAttributes.CopyObjectAttributesTo <InitialiseTo>(vi.declaration, context.OutputAttributes, useDecl);
context.InputAttributes.CopyObjectAttributesTo <DerivMessage>(vi.declaration, context.OutputAttributes, useDecl);
context.OutputAttributes.Set(useDecl, usageChannel);
context.OutputAttributes.Set(useDecl, new DescriptionAttribute("use of '" + ivd.Name + "'"));
context.OutputAttributes.Remove <InitialiseTo>(vi.declaration);
SetMarginalPrototype(useDecl);
}
private IVariableDeclaration CreateUseChannel(VariableInformation vi, IList <IStatement> stmts)
{
IVariableDeclaration useDecl = vi.DeriveIndexedVariable(stmts, context, vi.Name + "_use");
ChannelInfo usageChannel = ChannelInfo.UseChannel(vi);
usageChannel.decl = useDecl;
context.InputAttributes.CopyObjectAttributesTo <InitialiseTo>(vi.declaration, context.OutputAttributes, useDecl);
context.InputAttributes.CopyObjectAttributesTo <DerivMessage>(vi.declaration, context.OutputAttributes, useDecl);
context.OutputAttributes.Set(useDecl, usageChannel);
context.OutputAttributes.Set(useDecl, new DescriptionAttribute("use of '" + vi.Name + "'"));
context.OutputAttributes.Remove <InitialiseTo>(vi.declaration);
// The following lines are needed for AddMarginalStatements
VariableInformation useInformation = VariableInformation.GetVariableInformation(context, useDecl);
useInformation.IsStochastic = true;
return(useDecl);
}
private VariableToChannelInformation DeclareUsesArray(IList <IStatement> stmts, IVariableDeclaration ivd, VariableInformation vi, int useCount, int usageDepth)
{
// Create AnyIndex expressions up to usageDepth
List <IList <IExpression> > prefixSizes = new List <IList <IExpression> >();
List <IList <IExpression> > prefixVars = new List <IList <IExpression> >();
vi.DefineAllIndexVars(context);
for (int d = 0; d < usageDepth; d++)
{
IList <IExpression> sizeBracket = Builder.ExprCollection();
IList <IExpression> varBracket = Builder.ExprCollection();
for (int i = 0; i < vi.sizes[d].Length; i++)
{
sizeBracket.Add(Builder.StaticMethod(new Func <int>(GateAnalysisTransform.AnyIndex)));
varBracket.Add(Builder.VarRefExpr(vi.indexVars[d][i]));
}
prefixSizes.Add(sizeBracket);
prefixVars.Add(varBracket);
}
string prefix = vi.Name;
if (prefix.EndsWith("_use"))
{
prefix = prefix.Substring(0, prefix.Length - 4);
}
string arrayName = VariableInformation.GenerateName(context, prefix + "_uses");
IVariableDeclaration usesDecl = vi.DeriveArrayVariable(stmts, context, arrayName, Builder.LiteralExpr(useCount), Builder.VarDecl("_ind", typeof(int)),
prefixSizes, prefixVars, useLiteralIndices: true);
context.OutputAttributes.Remove <ChannelInfo>(usesDecl);
context.OutputAttributes.Add(usesDecl, new DescriptionAttribute($"uses of '{vi.Name}'"));
ChannelInfo ci = ChannelInfo.UseChannel(vi);
ci.decl = usesDecl;
context.OutputAttributes.Set(usesDecl, ci);
VariableToChannelInformation vtci = new VariableToChannelInformation();
vtci.usesDecl = usesDecl;
vtci.usageDepth = usageDepth;
usesOfVariable[ivd] = vtci;
return(vtci);
}
protected IExpression ConvertWithReplication(IExpression expr)
{
IVariableDeclaration baseVar = Recognizer.GetVariableDeclaration(expr);
// Check if this is an index local variable
if (baseVar == null) return expr;
// Check if the variable is stochastic
if (!CodeRecognizer.IsStochastic(context, baseVar)) return expr;
// Get the loop context for this variable
LoopContext lc = context.InputAttributes.Get<LoopContext>(baseVar);
if (lc == null)
{
Error("Loop context not found for '" + baseVar.Name + "'.");
return expr;
}
// Get the reference loop context for this expression
RefLoopContext rlc = lc.GetReferenceLoopContext(context);
// If the reference is in the same loop context as the declaration, do nothing.
if (rlc.loops.Count == 0) return expr;
// the set of loop variables that are constant wrt the expr
Set<IVariableDeclaration> constantLoopVars = new Set<IVariableDeclaration>();
constantLoopVars.AddRange(lc.loopVariables);
// collect set of all loop variable indices in the expression
Set<int> embeddedLoopIndices = new Set<int>();
List<IList<IExpression>> brackets = Recognizer.GetIndices(expr);
foreach (IList<IExpression> bracket in brackets)
{
foreach (IExpression index in bracket)
{
IExpression indExpr = index;
if (indExpr is IBinaryExpression ibe)
{
indExpr = ibe.Left;
}
IVariableDeclaration indVar = Recognizer.GetVariableDeclaration(indExpr);
if (indVar != null)
{
if (!constantLoopVars.Contains(indVar))
{
int loopIndex = rlc.loopVariables.IndexOf(indVar);
if (loopIndex != -1)
{
// indVar is a loop variable
constantLoopVars.Add(rlc.loopVariables[loopIndex]);
}
else
{
// indVar is not a loop variable
LoopContext lc2 = context.InputAttributes.Get<LoopContext>(indVar);
foreach (var ivd in lc2.loopVariables)
{
if (!constantLoopVars.Contains(ivd))
{
int loopIndex2 = rlc.loopVariables.IndexOf(ivd);
if (loopIndex2 != -1)
embeddedLoopIndices.Add(loopIndex2);
else
Error($"Index {ivd} is not in {rlc} for expression {expr}");
}
}
}
}
}
else
{
foreach(var ivd in Recognizer.GetVariables(indExpr))
{
if (!constantLoopVars.Contains(ivd))
{
// copied from above
LoopContext lc2 = context.InputAttributes.Get<LoopContext>(ivd);
foreach (var ivd2 in lc2.loopVariables)
{
if (!constantLoopVars.Contains(ivd2))
{
int loopIndex2 = rlc.loopVariables.IndexOf(ivd2);
if (loopIndex2 != -1)
embeddedLoopIndices.Add(loopIndex2);
else
Error($"Index {ivd2} is not in {rlc} for expression {expr}");
}
}
}
}
}
}
}
// Find loop variables that must be constant due to condition statements.
List<IStatement> ancestors = context.FindAncestors<IStatement>();
foreach (IStatement ancestor in ancestors)
{
if (!(ancestor is IConditionStatement ics))
continue;
ConditionBinding binding = new ConditionBinding(ics.Condition);
IVariableDeclaration ivd = Recognizer.GetVariableDeclaration(binding.lhs);
IVariableDeclaration ivd2 = Recognizer.GetVariableDeclaration(binding.rhs);
int index = rlc.loopVariables.IndexOf(ivd);
if (index >= 0 && IsConstantWrtLoops(ivd2, constantLoopVars))
{
constantLoopVars.Add(ivd);
continue;
}
int index2 = rlc.loopVariables.IndexOf(ivd2);
if (index2 >= 0 && IsConstantWrtLoops(ivd, constantLoopVars))
{
constantLoopVars.Add(ivd2);
continue;
}
}
// Determine if this expression is being defined (is on the LHS of an assignment)
bool isDef = Recognizer.IsBeingMutated(context, expr);
Containers containers = context.InputAttributes.Get<Containers>(baseVar);
IExpression originalExpr = expr;
for (int currentLoop = 0; currentLoop < rlc.loopVariables.Count; currentLoop++)
{
IVariableDeclaration loopVar = rlc.loopVariables[currentLoop];
if (constantLoopVars.Contains(loopVar))
continue;
IForStatement loop = rlc.loops[currentLoop];
// must replicate across this loop.
if (isDef)
{
Error("Cannot re-define a variable in a loop. Variables on the left hand side of an assignment must be indexed by all containing loops.");
continue;
}
if (embeddedLoopIndices.Contains(currentLoop))
{
string warningText = "This model will consume excess memory due to the indexing expression {0} inside of a loop over {1}. Try simplifying this expression in your model, perhaps by creating auxiliary index arrays.";
Warning(string.Format(warningText, originalExpr, loopVar.Name));
}
// split expr into a target and extra indices, where target will be replicated and extra indices will be added later
var extraIndices = new List<IEnumerable<IExpression>>();
AddUnreplicatedIndices(rlc.loops[currentLoop], expr, extraIndices, out IExpression exprToReplicate);
VariableInformation varInfo = VariableInformation.GetVariableInformation(context, baseVar);
IExpression loopSize = Recognizer.LoopSizeExpression(loop);
IList<IStatement> stmts = Builder.StmtCollection();
List<IList<IExpression>> inds = Recognizer.GetIndices(exprToReplicate);
IVariableDeclaration newIndexVar = loopVar;
// if loopVar is already an indexVar of varInfo, create a new variable
if (varInfo.HasIndexVar(loopVar))
{
newIndexVar = VariableInformation.GenerateLoopVar(context, "_a");
context.InputAttributes.CopyObjectAttributesTo(loopVar, context.OutputAttributes, newIndexVar);
}
IVariableDeclaration repVar = varInfo.DeriveArrayVariable(stmts, context, VariableInformation.GenerateName(context, varInfo.Name + "_rep"),
loopSize, newIndexVar, inds, useArrays: true);
if (!context.InputAttributes.Has<DerivedVariable>(repVar))
context.OutputAttributes.Set(repVar, new DerivedVariable());
if (context.InputAttributes.Has<ChannelInfo>(baseVar))
{
VariableInformation repVarInfo = VariableInformation.GetVariableInformation(context, repVar);
ChannelInfo ci = ChannelInfo.UseChannel(repVarInfo);
ci.decl = repVar;
context.OutputAttributes.Set(repVar, ci);
}
// Create replicate factor
Type returnType = Builder.ToType(repVar.VariableType);
IMethodInvokeExpression repMethod = Builder.StaticGenericMethod(
new Func<PlaceHolder, int, PlaceHolder[]>(Clone.Replicate),
new Type[] {returnType.GetElementType()}, exprToReplicate, loopSize);
IExpression assignExpression = Builder.AssignExpr(Builder.VarRefExpr(repVar), repMethod);
// Copy attributes across from variable to replication expression
context.InputAttributes.CopyObjectAttributesTo<Algorithm>(baseVar, context.OutputAttributes, repMethod);
context.InputAttributes.CopyObjectAttributesTo<DivideMessages>(baseVar, context.OutputAttributes, repMethod);
context.InputAttributes.CopyObjectAttributesTo<GivePriorityTo>(baseVar, context.OutputAttributes, repMethod);
stmts.Add(Builder.ExprStatement(assignExpression));
// add any containers missing from context.
containers = new Containers(context);
// RemoveUnusedLoops will also remove conditionals involving those loop variables.
// TODO: investigate whether removing these conditionals could cause a problem, e.g. when the condition is a conjunction of many terms.
containers = Containers.RemoveUnusedLoops(containers, context, repMethod);
if (context.InputAttributes.Has<DoNotSendEvidence>(baseVar)) containers = Containers.RemoveStochasticConditionals(containers, context);
//Containers shouldBeEmpty = containers.GetContainersNotInContext(context, context.InputStack.Count);
//if (shouldBeEmpty.inputs.Count > 0) { Error("Internal: Variable is out of scope"); return expr; }
if (containers.Contains(loop))
{
Error("Internal: invalid containers for replicating " + baseVar);
break;
}
int ancIndex = containers.GetMatchingAncestorIndex(context);
Containers missing = containers.GetContainersNotInContext(context, ancIndex);
stmts = Containers.WrapWithContainers(stmts, missing.inputs);
context.OutputAttributes.Set(repVar, containers);
List<IForStatement> loops = context.FindAncestors<IForStatement>(ancIndex);
foreach (IStatement container in missing.inputs)
{
if (container is IForStatement ifs) loops.Add(ifs);
}
context.OutputAttributes.Set(repVar, new LoopContext(loops));
// must convert the output since it may contain 'if' conditions
context.AddStatementsBeforeAncestorIndex(ancIndex, stmts, true);
baseVar = repVar;
expr = Builder.ArrayIndex(Builder.VarRefExpr(repVar), Builder.VarRefExpr(loopVar));
expr = Builder.JaggedArrayIndex(expr, extraIndices);
}
return expr;
}
protected void ProcessAssign(IExpression target, IExpression rhs, ref bool shouldDelete)
{
IVariableDeclaration ivd = Recognizer.GetVariableDeclaration(target);
if (ivd == null)
{
return;
}
if (rhs is IArrayCreateExpression)
{
IArrayCreateExpression iace = (IArrayCreateExpression)rhs;
bool zeroLength = iace.Dimensions.All(dimExpr =>
(dimExpr is ILiteralExpression) && ((ILiteralExpression)dimExpr).Value.Equals(0));
if (!zeroLength && iace.Initializer == null)
{
return; // variable will have assignments to elements
}
}
bool firstTime = !variablesAssigned.Contains(ivd);
variablesAssigned.Add(ivd);
bool isInferred = context.InputAttributes.Has <IsInferred>(ivd);
bool isStochastic = CodeRecognizer.IsStochastic(context, ivd);
if (!isStochastic)
{
return;
}
VariableInformation vi = VariableInformation.GetVariableInformation(context, ivd);
Containers defContainers = context.InputAttributes.Get <Containers>(ivd);
int ancIndex = defContainers.GetMatchingAncestorIndex(context);
Containers missing = defContainers.GetContainersNotInContext(context, ancIndex);
// definition of a stochastic variable
IExpression lhs = target;
if (lhs is IVariableDeclarationExpression)
{
lhs = Builder.VarRefExpr(ivd);
}
IExpression defExpr = lhs;
if (firstTime && isStochastic)
{
// Create a ChannelInfo attribute for use by later transforms, e.g. MessageTransform
ChannelInfo defChannel = ChannelInfo.DefChannel(vi);
defChannel.decl = ivd;
context.OutputAttributes.Set(ivd, defChannel);
}
bool isDerived = context.InputAttributes.Has <DerivedVariable>(ivd);
IAlgorithm algorithm = this.algorithmDefault;
Algorithm algAttr = context.InputAttributes.Get <Algorithm>(ivd);
if (algAttr != null)
{
algorithm = algAttr.algorithm;
}
if (algorithm is VariationalMessagePassing && ((VariationalMessagePassing)algorithm).UseDerivMessages && isDerived && firstTime)
{
vi.DefineAllIndexVars(context);
IList <IStatement> stmts = Builder.StmtCollection();
IVariableDeclaration derivDecl = vi.DeriveIndexedVariable(stmts, context, ivd.Name + "_deriv");
context.OutputAttributes.Set(ivd, new DerivMessage(derivDecl));
ChannelInfo derivChannel = ChannelInfo.DefChannel(vi);
derivChannel.decl = derivDecl;
context.OutputAttributes.Set(derivChannel.decl, derivChannel);
context.OutputAttributes.Set(derivChannel.decl, new DescriptionAttribute("deriv of '" + ivd.Name + "'"));
// Add the declarations
stmts = Containers.WrapWithContainers(stmts, missing.outputs);
context.AddStatementsBeforeAncestorIndex(ancIndex, stmts);
}
bool isPointEstimate = context.InputAttributes.Has <PointEstimate>(ivd);
if (this.analysis.variablesExcludingVariableFactor.Contains(ivd))
{
this.variablesLackingVariableFactor.Add(ivd);
// ivd will get a marginal channel in ConvertMethodInvoke
useOfVariable[ivd] = ivd;
return;
}
if (isDerived && !isInferred && !isPointEstimate)
{
return;
}
IExpression useExpr2 = null;
if (firstTime)
{
// create marginal and use channels
vi.DefineAllIndexVars(context);
IList <IStatement> stmts = Builder.StmtCollection();
CreateMarginalChannel(ivd, vi, stmts);
if (isStochastic)
{
CreateUseChannel(ivd, vi, stmts);
context.InputAttributes.Set(useOfVariable[ivd], defContainers);
}
// Add the declarations
stmts = Containers.WrapWithContainers(stmts, missing.outputs);
context.AddStatementsBeforeAncestorIndex(ancIndex, stmts);
}
if (isStochastic && !useOfVariable.ContainsKey(ivd))
{
Error("cannot find use channel of " + ivd);
return;
}
IExpression marginalExpr = Builder.ReplaceVariable(lhs, ivd, marginalOfVariable[ivd]);
IExpression useExpr = isStochastic ? Builder.ReplaceVariable(lhs, ivd, useOfVariable[ivd]) : marginalExpr;
InitialiseTo it = context.InputAttributes.Get <InitialiseTo>(ivd);
Type[] genArgs = new Type[] { defExpr.GetExpressionType() };
if (rhs is IMethodInvokeExpression)
{
IMethodInvokeExpression imie = (IMethodInvokeExpression)rhs;
if (Recognizer.IsStaticGenericMethod(imie, new Func <PlaceHolder, PlaceHolder>(Clone.Copy)) && ancIndex < context.InputStack.Count - 2)
{
IExpression arg = imie.Arguments[0];
IVariableDeclaration ivd2 = Recognizer.GetVariableDeclaration(arg);
if (ivd2 != null && context.InputAttributes.Get <MarginalPrototype>(ivd) == context.InputAttributes.Get <MarginalPrototype>(ivd2))
{
// if a variable is a copy, use the original expression since it will give more precise dependencies.
defExpr = arg;
shouldDelete = true;
bool makeClone = false;
if (makeClone)
{
VariableInformation vi2 = VariableInformation.GetVariableInformation(context, ivd2);
IList <IStatement> stmts = Builder.StmtCollection();
List <IList <IExpression> > indices = Recognizer.GetIndices(defExpr);
IVariableDeclaration useDecl2 = vi2.DeriveIndexedVariable(stmts, context, ivd2.Name + "_use", indices);
useExpr2 = Builder.VarRefExpr(useDecl2);
Containers defContainers2 = context.InputAttributes.Get <Containers>(ivd2);
int ancIndex2 = defContainers2.GetMatchingAncestorIndex(context);
Containers missing2 = defContainers2.GetContainersNotInContext(context, ancIndex2);
stmts = Containers.WrapWithContainers(stmts, missing2.outputs);
context.AddStatementsBeforeAncestorIndex(ancIndex2, stmts);
context.InputAttributes.Set(useDecl2, defContainers2);
// TODO: call CreateUseChannel
ChannelInfo usageChannel = ChannelInfo.UseChannel(vi2);
usageChannel.decl = useDecl2;
context.InputAttributes.CopyObjectAttributesTo <InitialiseTo>(vi.declaration, context.OutputAttributes, useDecl2);
context.InputAttributes.CopyObjectAttributesTo <DerivMessage>(vi.declaration, context.OutputAttributes, useDecl2);
context.OutputAttributes.Set(useDecl2, usageChannel);
//context.OutputAttributes.Set(useDecl2, new DescriptionAttribute("use of '" + ivd.Name + "'"));
context.OutputAttributes.Remove <InitialiseTo>(vi.declaration);
IExpression copyExpr = Builder.StaticGenericMethod(
new Func <PlaceHolder, PlaceHolder>(Clone.Copy), genArgs, useExpr2);
var copyStmt = Builder.AssignStmt(useExpr, copyExpr);
context.AddStatementAfterCurrent(copyStmt);
}
}
}
}
// Add the variable factor
IExpression variableFactorExpr;
bool isGateExitRandom = context.InputAttributes.Has <VariationalMessagePassing.GateExitRandomVariable>(ivd);
if (isGateExitRandom)
{
variableFactorExpr = Builder.StaticGenericMethod(
new Models.FuncOut <PlaceHolder, PlaceHolder, PlaceHolder>(Gate.ExitingVariable),
genArgs, defExpr, marginalExpr);
}
else
{
Delegate d = algorithm.GetVariableFactor(isDerived, it != null);
if (isPointEstimate)
{
d = new Models.FuncOut <PlaceHolder, PlaceHolder, PlaceHolder>(Clone.VariablePoint);
}
if (it == null)
{
variableFactorExpr = Builder.StaticGenericMethod(d, genArgs, defExpr, marginalExpr);
}
else
{
IExpression initExpr = Builder.ReplaceExpression(lhs, Builder.VarRefExpr(ivd), it.initialMessagesExpression);
variableFactorExpr = Builder.StaticGenericMethod(d, genArgs, defExpr, initExpr, marginalExpr);
}
}
context.InputAttributes.CopyObjectAttributesTo <GivePriorityTo>(ivd, context.OutputAttributes, variableFactorExpr);
context.InputAttributes.CopyObjectAttributesTo <Algorithm>(ivd, context.OutputAttributes, variableFactorExpr);
if (isStochastic)
{
context.OutputAttributes.Set(variableFactorExpr, new IsVariableFactor());
}
var assignStmt = Builder.AssignStmt(useExpr2 == null ? useExpr : useExpr2, variableFactorExpr);
context.AddStatementAfterCurrent(assignStmt);
}
/// <summary>
/// Converts a variable declaration by creating definition, marginal and uses channel variables.
/// </summary>
protected override IExpression ConvertVariableDeclExpr(IVariableDeclarationExpression ivde)
{
IVariableDeclaration ivd = ivde.Variable;
VariableInformation vi = VariableInformation.GetVariableInformation(context, ivd);
// If the variable is deterministic, return
if (!vi.IsStochastic)
{
ProcessConstant(ivd);
context.OutputAttributes.Set(ivd, new DescriptionAttribute("The constant '" + ivd.Name + "'"));
return(ivde);
}
bool suppressVariableFactor = context.InputAttributes.Has <SuppressVariableFactor>(ivd);
bool isDerived = context.InputAttributes.Has <DerivedVariable>(ivd);
bool isConstant = false;
bool isInferred = context.InputAttributes.Has <IsInferred>(ivd);
int useCount;
ChannelAnalysisTransform.UsageInfo info;
if (!analysis.usageInfo.TryGetValue(ivd, out info))
{
useCount = 0;
}
else
{
useCount = info.NumberOfUsesOld;
}
if (!(algorithm is Algorithms.GibbsSampling) && !isConstant && !suppressVariableFactor && (useCount == 1) && !isInferred && isDerived)
{
// this is optional
suppressVariableFactor = true;
context.InputAttributes.Set(ivd, new SuppressVariableFactor());
}
context.InputAttributes.Remove <LoopContext>(ivd);
context.InputAttributes.Set(ivd, new LoopContext(context));
// Create variable-to-channel information for the variable.
VariableToChannelInformation vtc = new VariableToChannelInformation();
vtc.shareAllUses = (useCount == 1);
Context.InputAttributes.Set(ivd, vtc);
// Ensure the marginal prototype is set.
MarginalPrototype mpa = Context.InputAttributes.Get <MarginalPrototype>(ivd);
try
{
vi.SetMarginalPrototypeFromAttribute(mpa);
}
catch (ArgumentException ex)
{
Error(ex.Message);
}
// Create the definition channel
vtc.defChannel = ChannelInfo.DefChannel(vi);
vtc.defChannel.decl = ivd;
// Always create a variable factor for a stochastic variable
if (!isConstant && !suppressVariableFactor)
{
vi.DefineAllIndexVars(context);
IList <IStatement> stmts = Builder.StmtCollection();
// Create marginal channel
vtc.marginalChannel = ChannelInfo.MarginalChannel(vi);
vtc.marginalChannel.decl = vi.DeriveIndexedVariable(stmts, context, vi.Name + "_marginal");
context.InputAttributes.CopyObjectAttributesTo <InitialiseTo>(vi.declaration, context.OutputAttributes, vtc.marginalChannel.decl);
context.OutputAttributes.Set(vtc.marginalChannel.decl, vtc.marginalChannel);
context.OutputAttributes.Set(vtc.marginalChannel.decl, new DescriptionAttribute("marginal of '" + ivd.Name + "'"));
SetMarginalPrototype(vtc.marginalChannel.decl);
if (algorithm is GibbsSampling && ((GibbsSampling)algorithm).UseSideChannels)
{
Type marginalType = MessageTransform.GetDistributionType(vi.varType, vi.InnermostElementType,
vi.marginalPrototypeExpression.GetExpressionType(), true);
Type domainType = ivd.VariableType.DotNetType;
vtc.samplesChannel = ChannelInfo.MarginalChannel(vi);
vtc.samplesChannel.decl = vi.DeriveIndexedVariable(stmts, context, vi.Name + "_samples");
context.OutputAttributes.Remove <InitialiseTo>(vtc.samplesChannel.decl);
context.OutputAttributes.Set(vtc.samplesChannel.decl, vtc.samplesChannel);
context.OutputAttributes.Set(vtc.samplesChannel.decl, new DescriptionAttribute("samples of '" + ivd.Name + "'"));
Type samplesType = typeof(List <>).MakeGenericType(domainType);
IExpression samples_mpe = Builder.NewObject(samplesType);
VariableInformation samples_vi = VariableInformation.GetVariableInformation(context, vtc.samplesChannel.decl);
samples_vi.marginalPrototypeExpression = samples_mpe;
vtc.conditionalsChannel = ChannelInfo.MarginalChannel(vi);
vtc.conditionalsChannel.decl = vi.DeriveIndexedVariable(stmts, context, vi.Name + "_conditionals");
context.OutputAttributes.Remove <InitialiseTo>(vtc.conditionalsChannel.decl);
context.OutputAttributes.Set(vtc.conditionalsChannel.decl, vtc.conditionalsChannel);
context.OutputAttributes.Set(vtc.conditionalsChannel.decl, new DescriptionAttribute("conditionals of '" + ivd.Name + "'"));
Type conditionalsType = typeof(List <>).MakeGenericType(marginalType);
IExpression conditionals_mpe = Builder.NewObject(conditionalsType);
VariableInformation conditionals_vi = VariableInformation.GetVariableInformation(context, vtc.conditionalsChannel.decl);
conditionals_vi.marginalPrototypeExpression = conditionals_mpe;
}
else
{
vtc.samplesChannel = vtc.marginalChannel;
vtc.conditionalsChannel = vtc.marginalChannel;
}
// Create uses channel
vtc.usageChannel = ChannelInfo.UseChannel(vi);
vtc.usageChannel.decl = vi.DeriveArrayVariable(stmts, context, vi.Name + "_uses", Builder.LiteralExpr(useCount), Builder.VarDecl("_ind", typeof(int)), useLiteralIndices: true);
context.InputAttributes.CopyObjectAttributesTo <InitialiseTo>(vi.declaration, context.OutputAttributes, vtc.usageChannel.decl);
context.OutputAttributes.Set(vtc.usageChannel.decl, vtc.usageChannel);
context.OutputAttributes.Set(vtc.usageChannel.decl, new DescriptionAttribute("uses of '" + ivd.Name + "'"));
SetMarginalPrototype(vtc.usageChannel.decl);
//setAllGroupRoots(context, ivd, false);
context.AddStatementsBeforeCurrent(stmts);
// Append usageDepth indices to def/marginal/use expressions
IExpression defExpr = Builder.VarRefExpr(ivd);
IExpression marginalExpr = Builder.VarRefExpr(vtc.marginalChannel.decl);
IExpression usageExpr = Builder.VarRefExpr(vtc.usageChannel.decl);
IExpression countExpr = Builder.LiteralExpr(useCount);
// Add clone factor tying together all of the channels
IMethodInvokeExpression usesEqualDefExpression;
Type[] genArgs = new Type[] { vi.varType };
if (algorithm is GibbsSampling && ((GibbsSampling)algorithm).UseSideChannels)
{
GibbsSampling gs = (GibbsSampling)algorithm;
IExpression burnInExpr = Builder.LiteralExpr(gs.BurnIn);
IExpression thinExpr = Builder.LiteralExpr(gs.Thin);
IExpression samplesExpr = Builder.VarRefExpr(vtc.samplesChannel.decl);
IExpression conditionalsExpr = Builder.VarRefExpr(vtc.conditionalsChannel.decl);
if (isDerived)
{
Delegate d = new FuncOut3 <PlaceHolder, int, int, int, PlaceHolder, PlaceHolder, PlaceHolder, PlaceHolder[]>(Factor.ReplicateWithMarginalGibbs);
usesEqualDefExpression = Builder.StaticGenericMethod(d, genArgs, defExpr, countExpr, burnInExpr, thinExpr, marginalExpr, samplesExpr, conditionalsExpr);
}
else
{
Delegate d = new FuncOut3 <PlaceHolder, int, int, int, PlaceHolder, PlaceHolder, PlaceHolder, PlaceHolder[]>(Factor.UsesEqualDefGibbs);
usesEqualDefExpression = Builder.StaticGenericMethod(d, genArgs, defExpr, countExpr, burnInExpr, thinExpr, marginalExpr, samplesExpr, conditionalsExpr);
}
}
else
{
Delegate d;
if (isDerived)
{
d = new FuncOut <PlaceHolder, int, PlaceHolder, PlaceHolder[]>(Factor.ReplicateWithMarginal <PlaceHolder>);
}
else
{
d = new FuncOut <PlaceHolder, int, PlaceHolder, PlaceHolder[]>(Factor.UsesEqualDef <PlaceHolder>);
}
usesEqualDefExpression = Builder.StaticGenericMethod(d, genArgs, defExpr, countExpr, marginalExpr);
}
if (isDerived)
{
context.OutputAttributes.Set(usesEqualDefExpression, new DerivedVariable()); // used by Gibbs
}
// Mark this as a pseudo-factor
context.OutputAttributes.Set(usesEqualDefExpression, new IsVariableFactor());
if (useCount == 1)
{
context.OutputAttributes.Set(usesEqualDefExpression, new DivideMessages(false));
}
else
{
context.InputAttributes.CopyObjectAttributesTo <DivideMessages>(ivd, context.OutputAttributes, usesEqualDefExpression);
}
context.InputAttributes.CopyObjectAttributesTo <GivePriorityTo>(ivd, context.OutputAttributes, usesEqualDefExpression);
IAssignExpression assignExpr = Builder.AssignExpr(usageExpr, usesEqualDefExpression);
// Copy attributes across from input to output
Context.InputAttributes.CopyObjectAttributesTo <Algorithm>(ivd, context.OutputAttributes, assignExpr);
context.OutputAttributes.Remove <InitialiseTo>(ivd);
if (vi.ArrayDepth == 0)
{
// Insert the UsesEqualDef statement after the declaration.
// Note the variable will not have been defined yet.
context.AddStatementAfterCurrent(Builder.ExprStatement(assignExpr));
}
else
{
// For an array, the UsesEqualDef statement should be inserted after the array is allocated.
// Store the statement for later use by ConvertArrayCreate.
context.InputAttributes.Remove <LoopContext>(ivd);
context.InputAttributes.Set(ivd, new LoopContext(context));
context.InputAttributes.Remove <Containers>(ivd);
context.InputAttributes.Set(ivd, new Containers(context));
vtc.usesEqualDefsStatements = Builder.StmtCollection();
vtc.usesEqualDefsStatements.Add(Builder.ExprStatement(assignExpr));
}
}
// These must be set after the above or they will be copied to the other channels
context.OutputAttributes.Set(ivd, vtc.defChannel);
context.OutputAttributes.Set(vtc.defChannel.decl, new DescriptionAttribute("definition of '" + ivd.Name + "'"));
return(ivde);
}
protected IExpression ConvertWithReplication(IExpression expr)
{
IVariableDeclaration baseVar = Recognizer.GetVariableDeclaration(expr);
// Check if this is an index local variable
if (baseVar == null)
{
return(expr);
}
// Check if the variable is stochastic
if (!CodeRecognizer.IsStochastic(context, baseVar))
{
return(expr);
}
if (cutVariables.Contains(baseVar))
{
return(expr);
}
// Get the repeat context for this variable
RepeatContext lc = context.InputAttributes.Get <RepeatContext>(baseVar);
if (lc == null)
{
Error("Repeat context not found for '" + baseVar.Name + "'.");
return(expr);
}
// Get the reference loop context for this expression
var rlc = lc.GetReferenceRepeatContext(context);
// If the reference is in the same loop context as the declaration, do nothing.
if (rlc.repeats.Count == 0)
{
return(expr);
}
// Determine if this expression is being defined (is on the LHS of an assignment)
bool isDef = Recognizer.IsBeingMutated(context, expr);
Containers containers = context.InputAttributes.Get <Containers>(baseVar);
for (int currentRepeat = 0; currentRepeat < rlc.repeatCounts.Count; currentRepeat++)
{
IExpression repeatCount = rlc.repeatCounts[currentRepeat];
IRepeatStatement repeat = rlc.repeats[currentRepeat];
// must replicate across this loop.
if (isDef)
{
Error("Cannot re-define a variable in a repeat block.");
continue;
}
// are we replicating the argument of Gate.Cases?
IMethodInvokeExpression imie = context.FindAncestor <IMethodInvokeExpression>();
if (imie != null)
{
if (Recognizer.IsStaticMethod(imie, typeof(Gate), "Cases"))
{
Error("'if(" + expr + ")' should be placed outside 'repeat(" + repeatCount + ")'");
}
if (Recognizer.IsStaticMethod(imie, typeof(Gate), "CasesInt"))
{
Error("'case(" + expr + ")' or 'switch(" + expr + ")' should be placed outside 'repeat(" + repeatCount + ")'");
}
}
VariableInformation varInfo = VariableInformation.GetVariableInformation(context, baseVar);
IList <IStatement> stmts = Builder.StmtCollection();
List <IList <IExpression> > inds = Recognizer.GetIndices(expr);
IVariableDeclaration repVar = varInfo.DeriveIndexedVariable(stmts, context, VariableInformation.GenerateName(context, varInfo.Name + "_rpt"), inds);
if (!context.InputAttributes.Has <DerivedVariable>(repVar))
{
context.OutputAttributes.Set(repVar, new DerivedVariable());
}
if (context.InputAttributes.Has <ChannelInfo>(baseVar))
{
VariableInformation repVarInfo = VariableInformation.GetVariableInformation(context, repVar);
ChannelInfo ci = ChannelInfo.UseChannel(repVarInfo);
ci.decl = repVar;
context.OutputAttributes.Set(repVar, ci);
}
// set the RepeatContext of repVar to include all repeats up to this one (so that it doesn't get Entered again)
List <IRepeatStatement> repeats = new List <IRepeatStatement>(lc.repeats);
for (int i = 0; i <= currentRepeat; i++)
{
repeats.Add(rlc.repeats[i]);
}
context.OutputAttributes.Remove <RepeatContext>(repVar);
context.OutputAttributes.Set(repVar, new RepeatContext(repeats));
// Create replicate factor
Type returnType = Builder.ToType(repVar.VariableType);
IMethodInvokeExpression powerPlateMethod = Builder.StaticGenericMethod(
new Func <PlaceHolder, double, PlaceHolder>(PowerPlate.Enter),
new Type[] { returnType }, expr, repeatCount);
IExpression assignExpression = Builder.AssignExpr(Builder.VarRefExpr(repVar), powerPlateMethod);
// Copy attributes across from variable to replication expression
context.InputAttributes.CopyObjectAttributesTo <Algorithm>(baseVar, context.OutputAttributes, powerPlateMethod);
context.InputAttributes.CopyObjectAttributesTo <DivideMessages>(baseVar, context.OutputAttributes, powerPlateMethod);
context.InputAttributes.CopyObjectAttributesTo <GivePriorityTo>(baseVar, context.OutputAttributes, powerPlateMethod);
stmts.Add(Builder.ExprStatement(assignExpression));
// add any containers missing from context.
containers = new Containers(context);
// remove inner repeats
for (int i = currentRepeat + 1; i < rlc.repeatCounts.Count; i++)
{
containers = containers.RemoveOneRepeat(rlc.repeats[i]);
}
context.OutputAttributes.Set(repVar, containers);
containers = containers.RemoveOneRepeat(repeat);
containers = Containers.RemoveUnusedLoops(containers, context, powerPlateMethod);
if (context.InputAttributes.Has <DoNotSendEvidence>(baseVar))
{
containers = Containers.RemoveStochasticConditionals(containers, context);
}
//Containers shouldBeEmpty = containers.GetContainersNotInContext(context, context.InputStack.Count);
//if (shouldBeEmpty.inputs.Count > 0) { Error("Internal: Variable is out of scope"); return expr; }
int ancIndex = containers.GetMatchingAncestorIndex(context);
Containers missing = containers.GetContainersNotInContext(context, ancIndex);
stmts = Containers.WrapWithContainers(stmts, missing.inputs);
// must convert the output since it may contain 'if' conditions
context.AddStatementsBeforeAncestorIndex(ancIndex, stmts, true);
baseVar = repVar;
expr = Builder.VarRefExpr(repVar);
}
return(expr);
}
private IExpression GetClone(IExpression expr)
{
// Determine if this is a definition i.e. the variable is on the left hand side of an assignment
// This must be done before base.ConvertArrayIndexer changes the expression!
if (Recognizer.IsBeingIndexed(context))
{
return(expr);
}
IVariableDeclaration baseVar = Recognizer.GetVariableDeclaration(expr);
// If not an indexed variable reference, skip it (e.g. an indexed argument reference)
if (baseVar == null)
{
return(expr);
}
DepthInfo depthInfo;
if (!analysis.depthInfos.TryGetValue(baseVar, out depthInfo))
{
return(expr);
}
if (depthInfo.useCount <= 1 || depthInfo.indexInfoOfDepth.Count == 1)
{
return(expr);
}
bool isEvidenceVar = context.InputAttributes.Has <DoNotSendEvidence>(baseVar);
if (isEvidenceVar && !cloneEvidenceVars)
{
return(expr);
}
int depth = Recognizer.GetIndexingDepth(expr);
IndexInfo info = depthInfo.indexInfoOfDepth[depth];
if (info.clone == null)
{
if (depth == depthInfo.definitionDepth)
{
return(expr);
}
VariableInformation varInfo = VariableInformation.GetVariableInformation(context, baseVar);
string name = baseVar.Name + "_depth" + depth;
IList <IStatement> stmts = Builder.StmtCollection();
// declare the clone
varInfo.DefineAllIndexVars(context);
IVariableDeclaration newvd = varInfo.DeriveIndexedVariable(stmts, context, name);
VariableInformation newVariableInformation = VariableInformation.GetVariableInformation(context, newvd);
newVariableInformation.LiteralIndexingDepth = info.literalIndexingDepth;
if (!context.InputAttributes.Has <DerivedVariable>(newvd))
{
context.InputAttributes.Set(newvd, new DerivedVariable());
}
if (context.InputAttributes.Has <ChannelInfo>(baseVar))
{
ChannelInfo ci = ChannelInfo.UseChannel(varInfo);
ci.decl = newvd;
context.OutputAttributes.Set(newvd, ci);
}
// define the clone
// if depth < definitionDepth, index by the definitionDepth
// else index by depth
// e.g.
// x[i] = definition
// x_depth0[i] = Copy(x[i])
// x_depth2[i][j] = Copy(x[i][j])
int indexingDepth = System.Math.Max(depth, depthInfo.definitionDepth);
IExpression lhs = Builder.VarRefExpr(newvd);
// TODO: clone the next lower depth, not always the baseVar
IExpression rhs = Builder.VarRefExpr(baseVar);
AddCopyStatements(stmts, newVariableInformation, indexingDepth, lhs, rhs);
// Reduce memory consumption by declaring the clone outside of unnecessary loops.
// This way, the item is cloned outside the loop and then replicated, instead of replicating the entire array and cloning the item.
Containers containers = info.containers;
containers = Containers.RemoveUnusedLoops(containers, context, Builder.VarRefExpr(baseVar));
if (context.InputAttributes.Has <DoNotSendEvidence>(baseVar))
{
containers = Containers.RemoveStochasticConditionals(containers, context);
}
// To put the declaration in the desired containers, we find an ancestor which includes as many of the containers as possible,
// then wrap the declaration with the remaining containers.
int ancIndex = containers.GetMatchingAncestorIndex(context);
Containers missing = containers.GetContainersNotInContext(context, ancIndex);
stmts = Containers.WrapWithContainers(stmts, missing.outputs);
context.AddStatementsBeforeAncestorIndex(ancIndex, stmts);
context.InputAttributes.Set(newvd, containers);
info.clone = Builder.VarRefExpr(newvd);
}
List <IList <IExpression> > indices = Recognizer.GetIndices(expr);
return(Builder.JaggedArrayIndex(info.clone, indices));
}
