/// <summary>
/// Modify array index expressions which are copies of other variables.
/// </summary>
/// <param name="iaie"></param>
/// <returns></returns>
protected override IExpression ConvertArrayIndexer(IArrayIndexerExpression iaie)
{
// should not convert if on LHS
IExpression copyExpr = GetCopyExpr(iaie);
if (copyExpr != null)
{
return(copyExpr);
}
formalTypeStack.Push(typeof(int));
IList <IExpression> newIndices = ConvertCollection(iaie.Indices);
formalTypeStack.Pop();
Type arrayType;
if (iaie.Indices.Count == 1)
{
var elementType = FormalTypeStackApplies() ? formalTypeStack.Peek() : iaie.GetExpressionType();
// This must be IReadOnlyList not IList to allow covariance.
arrayType = typeof(IReadOnlyList <>).MakeGenericType(elementType);
}
else
{
arrayType = iaie.Target.GetExpressionType();
}
formalTypeStack.Push(arrayType);
IExpression newTarget = ConvertExpression(iaie.Target);
formalTypeStack.Pop();
if (ReferenceEquals(newTarget, iaie.Target) &&
ReferenceEquals(newIndices, iaie.Indices))
{
return(iaie);
}
IArrayIndexerExpression aie = Builder.ArrayIndxrExpr();
aie.Target = newTarget;
aie.Indices.AddRange(newIndices);
Context.InputAttributes.CopyObjectAttributesTo(iaie, context.OutputAttributes, aie);
// Since part of the expression has been replaced, check the whole again
return(ConvertArrayIndexer(aie));
}
protected override IExpression ConvertArrayIndexer(IArrayIndexerExpression iaie)
{
IExpression expr = base.ConvertArrayIndexer(iaie);
foreach (IStatement container in openContainers)
{
Dictionary <IExpression, LocalAnalysisTransform.LocalInfo> localInfoOfExpr = localInfoOfStmt[container];
LocalAnalysisTransform.LocalInfo info;
if (localInfoOfExpr.TryGetValue(iaie, out info))
{
int depth = Recognizer.GetIndexingDepth(iaie);
if (ShouldUseLocal(info, depth))
{
object decl = Recognizer.GetDeclaration(expr);
if (info.localVar == null)
{
// name must end with a fixed suffix, to avoid clashes
string name = VariableInformation.GenerateName(context, MessageTransform.GetName(iaie) + "_local");
info.localVar = Builder.VarDecl(name, iaie.GetExpressionType());
}
if (!isTransformingContainer)
{
IExpression localExpr = Builder.VarRefExpr(info.localVar);
if (info.convertedCount == 0)
{
// this is the first conversion, so output a declaration and initializer
var declExpr = Builder.VarDeclExpr(info.localVar);
IStatement declSt = Builder.ExprStatement(declExpr);
// an initializer is needed to suppress compiler errors about 'Use of unassigned local variable'
declSt = Builder.AssignStmt(declExpr, Builder.DefaultExpr(info.localVar.VariableType));
int ancIndex = GetMatchingAncestorIndex(context, info.containingStatements);
context.AddStatementBeforeAncestorIndex(ancIndex, declSt);
if (info.hasReadBeforeWrite || info.minWriteDepth > depth)
{
// initialize the local from the array element
IStatement init = Builder.AssignStmt(localExpr, expr);
int ancIndex2 = info.containers.GetMatchingAncestorIndex(context);
Containers missing = info.containers.GetContainersNotInContext(context, ancIndex2);
init = Containers.WrapWithContainers(init, TransformContainers(missing.outputs));
context.AddStatementBeforeAncestorIndex(ancIndex2, init);
}
}
info.convertedCount++;
if (info.convertedCount == info.count)
{
if (info.hasWrite)
{
// this is the last appearance of the local, so update the array element from the local
IStatement st = Builder.AssignStmt(expr, localExpr);
int ancIndex2 = info.containers.GetMatchingAncestorIndex(context);
Containers missing = info.containers.GetContainersNotInContext(context, ancIndex2);
// containers may contain locals, so they must be transformed.
st = Containers.WrapWithContainers(st, TransformContainers(missing.outputs));
context.AddStatementAfterAncestorIndex(ancIndex2, st);
}
info.convertedCount = 0; // reset in case this variable appears in another block
}
}
return(Builder.VarRefExpr(info.localVar));
}
}
}
return(expr);
}
/// <summary>
/// This method does all the work of converting literal indexing expressions.
/// </summary>
/// <param name="iaie"></param>
/// <returns></returns>
protected override IExpression ConvertArrayIndexer(IArrayIndexerExpression iaie)
{
IndexAnalysisTransform.IndexInfo info;
if (!analysis.indexInfoOf.TryGetValue(iaie, out info))
{
return(base.ConvertArrayIndexer(iaie));
}
// 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!
bool isDef = Recognizer.IsBeingMutated(context, iaie);
if (info.clone != null)
{
if (isDef)
{
// check that extra literal indices in the target are zero.
// for example, if iae is x[i][0] = (...) then it is safe to add x_uses[i] = Rep(x[i])
// if iae is x[i][1] = (...) then it is safe to add x_uses[i][1] = Rep(x[i][1])
// but not x_uses[i] = Rep(x[i]) since this will be a duplicate.
bool extraLiteralsAreZero = true;
int parentIndex = context.InputStack.Count - 2;
object parent = context.GetAncestor(parentIndex);
while (parent is IArrayIndexerExpression)
{
IArrayIndexerExpression parent_iaie = (IArrayIndexerExpression)parent;
foreach (IExpression index in parent_iaie.Indices)
{
if (index is ILiteralExpression)
{
int value = (int)((ILiteralExpression)index).Value;
if (value != 0)
{
extraLiteralsAreZero = false;
break;
}
}
}
parentIndex--;
parent = context.GetAncestor(parentIndex);
}
if (false && extraLiteralsAreZero)
{
// change:
// array[0] = f()
// into:
// array_item0 = f()
// array[0] = Copy(array_item0)
IExpression copy = Builder.StaticGenericMethod(new Func <PlaceHolder, PlaceHolder>(Clone.Copy <PlaceHolder>), new Type[] { iaie.GetExpressionType() },
info.clone);
IStatement copySt = Builder.AssignStmt(iaie, copy);
context.AddStatementAfterCurrent(copySt);
}
}
return(info.clone);
}
if (isDef)
{
// do not clone the lhs of an array create assignment.
IAssignExpression assignExpr = context.FindAncestor <IAssignExpression>();
if (assignExpr.Expression is IArrayCreateExpression)
{
return(iaie);
}
}
IVariableDeclaration originalBaseVar = Recognizer.GetVariableDeclaration(iaie);
// If the variable is not stochastic, return
if (!CodeRecognizer.IsStochastic(context, originalBaseVar))
{
return(iaie);
}
IExpression newExpr = null;
IVariableDeclaration baseVar = originalBaseVar;
IVariableDeclaration newvd = null;
IExpression rhsExpr = null;
Containers containers = info.containers;
Type tp = iaie.GetExpressionType();
if (tp == null)
{
Error("Could not determine type of expression: " + iaie);
return(iaie);
}
var stmts = Builder.StmtCollection();
var stmtsAfter = Builder.StmtCollection();
// does the expression have the form array[indices[k]][indices2[k]][indices3[k]]?
if (newvd == null && UseGetItems && iaie.Target is IArrayIndexerExpression &&
iaie.Indices.Count == 1 && iaie.Indices[0] is IArrayIndexerExpression)
{
IArrayIndexerExpression index3 = (IArrayIndexerExpression)iaie.Indices[0];
IArrayIndexerExpression iaie2 = (IArrayIndexerExpression)iaie.Target;
if (index3.Indices.Count == 1 && index3.Indices[0] is IVariableReferenceExpression &&
iaie2.Target is IArrayIndexerExpression &&
iaie2.Indices.Count == 1 && iaie2.Indices[0] is IArrayIndexerExpression)
{
IArrayIndexerExpression index2 = (IArrayIndexerExpression)iaie2.Indices[0];
IArrayIndexerExpression iaie3 = (IArrayIndexerExpression)iaie2.Target;
if (index2.Indices.Count == 1 && index2.Indices[0] is IVariableReferenceExpression &&
iaie3.Indices.Count == 1 && iaie3.Indices[0] is IArrayIndexerExpression)
{
IArrayIndexerExpression index = (IArrayIndexerExpression)iaie3.Indices[0];
IVariableReferenceExpression innerIndex = (IVariableReferenceExpression)index.Indices[0];
IForStatement innerLoop = Recognizer.GetLoopForVariable(context, innerIndex);
if (index.Indices.Count == 1 && index2.Indices[0].Equals(innerIndex) &&
index3.Indices[0].Equals(innerIndex) &&
innerLoop != null && AreLoopsDisjoint(innerLoop, iaie3.Target, index.Target))
{
// expression has the form array[indices[k]][indices2[k]][indices3[k]]
if (isDef)
{
Error("fancy indexing not allowed on left hand side");
return(iaie);
}
WarnIfLocal(index.Target, iaie3.Target, iaie);
WarnIfLocal(index2.Target, iaie3.Target, iaie);
WarnIfLocal(index3.Target, iaie3.Target, iaie);
containers = RemoveReferencesTo(containers, innerIndex);
IExpression loopSize = Recognizer.LoopSizeExpression(innerLoop);
var indices = Recognizer.GetIndices(iaie);
// Build name of replacement variable from index values
StringBuilder sb = new StringBuilder("_item");
AppendIndexString(sb, iaie3);
AppendIndexString(sb, iaie2);
AppendIndexString(sb, iaie);
string name = ToString(iaie3.Target) + sb.ToString();
VariableInformation varInfo = VariableInformation.GetVariableInformation(context, baseVar);
newvd = varInfo.DeriveArrayVariable(stmts, context, name, loopSize, Recognizer.GetVariableDeclaration(innerIndex), indices);
if (!context.InputAttributes.Has <DerivedVariable>(newvd))
{
context.InputAttributes.Set(newvd, new DerivedVariable());
}
IExpression getItems = Builder.StaticGenericMethod(new Func <IReadOnlyList <IReadOnlyList <IReadOnlyList <PlaceHolder> > >, IReadOnlyList <int>, IReadOnlyList <int>, IReadOnlyList <int>, PlaceHolder[]>(Collection.GetItemsFromDeepJagged),
new Type[] { tp }, iaie3.Target, index.Target, index2.Target, index3.Target);
context.InputAttributes.CopyObjectAttributesTo <Algorithm>(baseVar, context.OutputAttributes, getItems);
stmts.Add(Builder.AssignStmt(Builder.VarRefExpr(newvd), getItems));
newExpr = Builder.ArrayIndex(Builder.VarRefExpr(newvd), innerIndex);
rhsExpr = getItems;
}
}
}
}
// does the expression have the form array[indices[k]][indices2[k]]?
if (newvd == null && UseGetItems && iaie.Target is IArrayIndexerExpression &&
iaie.Indices.Count == 1 && iaie.Indices[0] is IArrayIndexerExpression)
{
IArrayIndexerExpression index2 = (IArrayIndexerExpression)iaie.Indices[0];
IArrayIndexerExpression target = (IArrayIndexerExpression)iaie.Target;
if (index2.Indices.Count == 1 && index2.Indices[0] is IVariableReferenceExpression &&
target.Indices.Count == 1 && target.Indices[0] is IArrayIndexerExpression)
{
IVariableReferenceExpression innerIndex = (IVariableReferenceExpression)index2.Indices[0];
IArrayIndexerExpression index = (IArrayIndexerExpression)target.Indices[0];
IForStatement innerLoop = Recognizer.GetLoopForVariable(context, innerIndex);
if (index.Indices.Count == 1 && index.Indices[0].Equals(innerIndex) &&
innerLoop != null && AreLoopsDisjoint(innerLoop, target.Target, index.Target))
{
// expression has the form array[indices[k]][indices2[k]]
if (isDef)
{
Error("fancy indexing not allowed on left hand side");
return(iaie);
}
var innerLoops = new List <IForStatement>();
innerLoops.Add(innerLoop);
var indexTarget = index.Target;
var index2Target = index2.Target;
// check if the index array is jagged, i.e. array[indices[k][j]]
while (indexTarget is IArrayIndexerExpression && index2Target is IArrayIndexerExpression)
{
IArrayIndexerExpression indexTargetExpr = (IArrayIndexerExpression)indexTarget;
IArrayIndexerExpression index2TargetExpr = (IArrayIndexerExpression)index2Target;
if (indexTargetExpr.Indices.Count == 1 && indexTargetExpr.Indices[0] is IVariableReferenceExpression &&
index2TargetExpr.Indices.Count == 1 && index2TargetExpr.Indices[0] is IVariableReferenceExpression)
{
IVariableReferenceExpression innerIndexTarget = (IVariableReferenceExpression)indexTargetExpr.Indices[0];
IVariableReferenceExpression innerIndex2Target = (IVariableReferenceExpression)index2TargetExpr.Indices[0];
IForStatement indexTargetLoop = Recognizer.GetLoopForVariable(context, innerIndexTarget);
if (indexTargetLoop != null && AreLoopsDisjoint(indexTargetLoop, target.Target, indexTargetExpr.Target) &&
innerIndexTarget.Equals(innerIndex2Target))
{
innerLoops.Add(indexTargetLoop);
indexTarget = indexTargetExpr.Target;
index2Target = index2TargetExpr.Target;
}
else
{
break;
}
}
else
{
break;
}
}
WarnIfLocal(indexTarget, target.Target, iaie);
WarnIfLocal(index2Target, target.Target, iaie);
innerLoops.Reverse();
var loopSizes = innerLoops.ListSelect(ifs => new[] { Recognizer.LoopSizeExpression(ifs) });
var newIndexVars = innerLoops.ListSelect(ifs => new[] { Recognizer.LoopVariable(ifs) });
// Build name of replacement variable from index values
StringBuilder sb = new StringBuilder("_item");
AppendIndexString(sb, target);
AppendIndexString(sb, iaie);
string name = ToString(target.Target) + sb.ToString();
VariableInformation varInfo = VariableInformation.GetVariableInformation(context, baseVar);
var indices = Recognizer.GetIndices(iaie);
newvd = varInfo.DeriveArrayVariable(stmts, context, name, loopSizes, newIndexVars, indices);
if (!context.InputAttributes.Has <DerivedVariable>(newvd))
{
context.InputAttributes.Set(newvd, new DerivedVariable());
}
IExpression getItems;
if (innerLoops.Count == 1)
{
getItems = Builder.StaticGenericMethod(new Func <IReadOnlyList <IReadOnlyList <PlaceHolder> >, IReadOnlyList <int>, IReadOnlyList <int>, PlaceHolder[]>(Collection.GetItemsFromJagged),
new Type[] { tp }, target.Target, indexTarget, index2Target);
}
else if (innerLoops.Count == 2)
{
getItems = Builder.StaticGenericMethod(new Func <IReadOnlyList <IReadOnlyList <PlaceHolder> >, IReadOnlyList <IReadOnlyList <int> >, IReadOnlyList <IReadOnlyList <int> >, PlaceHolder[][]>(Collection.GetJaggedItemsFromJagged),
new Type[] { tp }, target.Target, indexTarget, index2Target);
}
else
{
throw new NotImplementedException($"innerLoops.Count = {innerLoops.Count}");
}
context.InputAttributes.CopyObjectAttributesTo <Algorithm>(baseVar, context.OutputAttributes, getItems);
stmts.Add(Builder.AssignStmt(Builder.VarRefExpr(newvd), getItems));
var newIndices = newIndexVars.ListSelect(ivds => Util.ArrayInit(ivds.Length, i => Builder.VarRefExpr(ivds[i])));
newExpr = Builder.JaggedArrayIndex(Builder.VarRefExpr(newvd), newIndices);
rhsExpr = getItems;
}
else if (HasAnyCommonLoops(index, index2))
{
Warning($"This model will consume excess memory due to the indexing expression {iaie} since {index} and {index2} have larger depth than the compiler can handle.");
}
}
}
if (newvd == null)
{
IArrayIndexerExpression originalExpr = iaie;
if (UseGetItems)
{
iaie = (IArrayIndexerExpression)base.ConvertArrayIndexer(iaie);
}
if (!object.ReferenceEquals(iaie.Target, originalExpr.Target) && false)
{
// TODO: determine if this warning is useful or not
string warningText = "This model may consume excess memory due to the jagged indexing expression {0}";
Warning(string.Format(warningText, originalExpr));
}
// get the baseVar of the new expression.
baseVar = Recognizer.GetVariableDeclaration(iaie);
VariableInformation varInfo = VariableInformation.GetVariableInformation(context, baseVar);
var indices = Recognizer.GetIndices(iaie);
// Build name of replacement variable from index values
StringBuilder sb = new StringBuilder("_item");
AppendIndexString(sb, iaie);
string name = ToString(iaie.Target) + sb.ToString();
// does the expression have the form array[indices[k]]?
if (UseGetItems && iaie.Indices.Count == 1 && iaie.Indices[0] is IArrayIndexerExpression)
{
IArrayIndexerExpression index = (IArrayIndexerExpression)iaie.Indices[0];
if (index.Indices.Count == 1 && index.Indices[0] is IVariableReferenceExpression)
{
// expression has the form array[indices[k]]
IVariableReferenceExpression innerIndex = (IVariableReferenceExpression)index.Indices[0];
IForStatement innerLoop = Recognizer.GetLoopForVariable(context, innerIndex);
if (innerLoop != null && AreLoopsDisjoint(innerLoop, iaie.Target, index.Target))
{
if (isDef)
{
Error("fancy indexing not allowed on left hand side");
return(iaie);
}
var innerLoops = new List <IForStatement>();
innerLoops.Add(innerLoop);
var indexTarget = index.Target;
// check if the index array is jagged, i.e. array[indices[k][j]]
while (indexTarget is IArrayIndexerExpression)
{
IArrayIndexerExpression index2 = (IArrayIndexerExpression)indexTarget;
if (index2.Indices.Count == 1 && index2.Indices[0] is IVariableReferenceExpression)
{
IVariableReferenceExpression innerIndex2 = (IVariableReferenceExpression)index2.Indices[0];
IForStatement innerLoop2 = Recognizer.GetLoopForVariable(context, innerIndex2);
if (innerLoop2 != null && AreLoopsDisjoint(innerLoop2, iaie.Target, index2.Target))
{
innerLoops.Add(innerLoop2);
indexTarget = index2.Target;
// This limit must match the number of handled cases below.
if (innerLoops.Count == 3)
{
break;
}
}
else
{
break;
}
}
else
{
break;
}
}
WarnIfLocal(indexTarget, iaie.Target, originalExpr);
innerLoops.Reverse();
var loopSizes = innerLoops.ListSelect(ifs => new[] { Recognizer.LoopSizeExpression(ifs) });
var newIndexVars = innerLoops.ListSelect(ifs => new[] { Recognizer.LoopVariable(ifs) });
newvd = varInfo.DeriveArrayVariable(stmts, context, name, loopSizes, newIndexVars, indices);
if (!context.InputAttributes.Has <DerivedVariable>(newvd))
{
context.InputAttributes.Set(newvd, new DerivedVariable());
}
IExpression getItems;
if (innerLoops.Count == 1)
{
getItems = Builder.StaticGenericMethod(new Func <IReadOnlyList <PlaceHolder>, IReadOnlyList <int>, PlaceHolder[]>(Collection.GetItems),
new Type[] { tp }, iaie.Target, indexTarget);
}
else if (innerLoops.Count == 2)
{
getItems = Builder.StaticGenericMethod(new Func <IReadOnlyList <PlaceHolder>, IReadOnlyList <IReadOnlyList <int> >, PlaceHolder[][]>(Collection.GetJaggedItems),
new Type[] { tp }, iaie.Target, indexTarget);
}
else if (innerLoops.Count == 3)
{
getItems = Builder.StaticGenericMethod(new Func <IReadOnlyList <PlaceHolder>, IReadOnlyList <IReadOnlyList <IReadOnlyList <int> > >, PlaceHolder[][][]>(Collection.GetDeepJaggedItems),
new Type[] { tp }, iaie.Target, indexTarget);
}
else
{
throw new NotImplementedException($"innerLoops.Count = {innerLoops.Count}");
}
context.InputAttributes.CopyObjectAttributesTo <Algorithm>(baseVar, context.OutputAttributes, getItems);
stmts.Add(Builder.AssignStmt(Builder.VarRefExpr(newvd), getItems));
var newIndices = newIndexVars.ListSelect(ivds => Util.ArrayInit(ivds.Length, i => Builder.VarRefExpr(ivds[i])));
newExpr = Builder.JaggedArrayIndex(Builder.VarRefExpr(newvd), newIndices);
rhsExpr = getItems;
}
}
}
if (newvd == null)
{
if (UseGetItems && info.count < 2)
{
return(iaie);
}
try
{
newvd = varInfo.DeriveIndexedVariable(stmts, context, name, indices, copyInitializer: isDef);
}
catch (Exception ex)
{
Error(ex.Message, ex);
return(iaie);
}
context.OutputAttributes.Remove <DerivedVariable>(newvd);
newExpr = Builder.VarRefExpr(newvd);
rhsExpr = iaie;
if (isDef)
{
// change:
// array[0] = f()
// into:
// array_item0 = f()
// array[0] = Copy(array_item0)
IExpression copy = Builder.StaticGenericMethod(new Func <PlaceHolder, PlaceHolder>(Clone.Copy), new Type[] { tp }, newExpr);
IStatement copySt = Builder.AssignStmt(iaie, copy);
stmtsAfter.Add(copySt);
if (!context.InputAttributes.Has <DerivedVariable>(baseVar))
{
context.InputAttributes.Set(baseVar, new DerivedVariable());
}
}
else if (!info.IsAssignedTo)
{
// change:
// x = f(array[0])
// into:
// array_item0 = Copy(array[0])
// x = f(array_item0)
IExpression copy = Builder.StaticGenericMethod(new Func <PlaceHolder, PlaceHolder>(Clone.Copy), new Type[] { tp }, iaie);
IStatement copySt = Builder.AssignStmt(Builder.VarRefExpr(newvd), copy);
//if (attr != null) context.OutputAttributes.Set(copySt, attr);
stmts.Add(copySt);
context.InputAttributes.Set(newvd, new DerivedVariable());
}
}
}
// 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.RemoveUnusedLoops(containers, context, rhsExpr);
if (context.InputAttributes.Has <DoNotSendEvidence>(originalBaseVar))
{
containers = Containers.RemoveStochasticConditionals(containers, context);
}
if (true)
{
IStatement st = GetBindingSetContainer(FilterBindingSet(info.bindings,
binding => Containers.ContainsExpression(containers.inputs, context, binding.GetExpression())));
if (st != null)
{
containers.Add(st);
}
}
// 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);
stmtsAfter = Containers.WrapWithContainers(stmtsAfter, missing.outputs);
context.AddStatementsAfterAncestorIndex(ancIndex, stmtsAfter);
context.InputAttributes.Set(newvd, containers);
info.clone = newExpr;
return(newExpr);
}
/// <summary>
/// This method does all the work of converting literal indexing expressions.
/// </summary>
/// <param name="iaie"></param>
/// <returns></returns>
protected override IExpression ConvertArrayIndexer(IArrayIndexerExpression iaie)
{
IndexAnalysisTransform.IndexInfo info;
if (!analysis.indexInfoOf.TryGetValue(iaie, out info))
{
return(base.ConvertArrayIndexer(iaie));
}
// 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!
bool isDef = Recognizer.IsBeingMutated(context, iaie);
if (info.clone != null)
{
if (isDef)
{
// check that extra literal indices in the target are zero.
// for example, if iae is x[i][0] = (...) then it is safe to add x_uses[i] = Rep(x[i])
// if iae is x[i][1] = (...) then it is safe to add x_uses[i][1] = Rep(x[i][1])
// but not x_uses[i] = Rep(x[i]) since this will be a duplicate.
bool extraLiteralsAreZero = true;
int parentIndex = context.InputStack.Count - 2;
object parent = context.GetAncestor(parentIndex);
while (parent is IArrayIndexerExpression parent_iaie)
{
foreach (IExpression index in parent_iaie.Indices)
{
if (index is ILiteralExpression ile)
{
int value = (int)ile.Value;
if (value != 0)
{
extraLiteralsAreZero = false;
break;
}
}
}
parentIndex--;
parent = context.GetAncestor(parentIndex);
}
if (false && extraLiteralsAreZero)
{
// change:
// array[0] = f()
// into:
// array_item0 = f()
// array[0] = Copy(array_item0)
IExpression copy = Builder.StaticGenericMethod(new Func <PlaceHolder, PlaceHolder>(Clone.Copy <PlaceHolder>), new Type[] { iaie.GetExpressionType() },
info.clone);
IStatement copySt = Builder.AssignStmt(iaie, copy);
context.AddStatementAfterCurrent(copySt);
}
}
return(info.clone);
}
if (isDef)
{
// do not clone the lhs of an array create assignment.
IAssignExpression assignExpr = context.FindAncestor <IAssignExpression>();
if (assignExpr.Expression is IArrayCreateExpression)
{
return(iaie);
}
}
IVariableDeclaration originalBaseVar = Recognizer.GetVariableDeclaration(iaie);
// If the variable is not stochastic, return
if (!CodeRecognizer.IsStochastic(context, originalBaseVar))
{
return(iaie);
}
IExpression newExpr = null;
IVariableDeclaration baseVar = originalBaseVar;
IVariableDeclaration newvd = null;
IExpression rhsExpr = null;
Containers containers = info.containers;
Type tp = iaie.GetExpressionType();
if (tp == null)
{
Error("Could not determine type of expression: " + iaie);
return(iaie);
}
var stmts = Builder.StmtCollection();
var stmtsAfter = Builder.StmtCollection();
// does the expression have the form array[indices[k]][indices2[k]][indices3[k]]?
if (newvd == null && UseGetItems && iaie.Indices.Count == 1)
{
if (iaie.Target is IArrayIndexerExpression iaie2 &&
iaie.Indices[0] is IArrayIndexerExpression index3 &&
index3.Indices.Count == 1 &&
index3.Indices[0] is IVariableReferenceExpression innerIndex3 &&
iaie2.Target is IArrayIndexerExpression iaie3 &&
iaie2.Indices.Count == 1 &&
iaie2.Indices[0] is IArrayIndexerExpression index2 &&
index2.Indices.Count == 1 &&
index2.Indices[0] is IVariableReferenceExpression innerIndex2 &&
innerIndex2.Equals(innerIndex3) &&
iaie3.Indices.Count == 1 &&
iaie3.Indices[0] is IArrayIndexerExpression index &&
index.Indices.Count == 1 &&
index.Indices[0] is IVariableReferenceExpression innerIndex &&
innerIndex.Equals(innerIndex2))
{
IForStatement innerLoop = Recognizer.GetLoopForVariable(context, innerIndex);
if (innerLoop != null &&
AreLoopsDisjoint(innerLoop, iaie3.Target, index.Target))
{
// expression has the form array[indices[k]][indices2[k]][indices3[k]]
if (isDef)
{
Error("fancy indexing not allowed on left hand side");
return(iaie);
}
WarnIfLocal(index.Target, iaie3.Target, iaie);
WarnIfLocal(index2.Target, iaie3.Target, iaie);
WarnIfLocal(index3.Target, iaie3.Target, iaie);
containers = RemoveReferencesTo(containers, innerIndex);
IExpression loopSize = Recognizer.LoopSizeExpression(innerLoop);
var indices = Recognizer.GetIndices(iaie);
// Build name of replacement variable from index values
StringBuilder sb = new StringBuilder("_item");
AppendIndexString(sb, iaie3);
AppendIndexString(sb, iaie2);
AppendIndexString(sb, iaie);
string name = ToString(iaie3.Target) + sb.ToString();
VariableInformation varInfo = VariableInformation.GetVariableInformation(context, baseVar);
newvd = varInfo.DeriveArrayVariable(stmts, context, name, loopSize, Recognizer.GetVariableDeclaration(innerIndex), indices);
if (!context.InputAttributes.Has <DerivedVariable>(newvd))
{
context.InputAttributes.Set(newvd, new DerivedVariable());
}
IExpression getItems = Builder.StaticGenericMethod(new Func <IReadOnlyList <IReadOnlyList <IReadOnlyList <PlaceHolder> > >, IReadOnlyList <int>, IReadOnlyList <int>, IReadOnlyList <int>, PlaceHolder[]>(Collection.GetItemsFromDeepJagged),
new Type[] { tp }, iaie3.Target, index.Target, index2.Target, index3.Target);
context.InputAttributes.CopyObjectAttributesTo <Algorithm>(baseVar, context.OutputAttributes, getItems);
stmts.Add(Builder.AssignStmt(Builder.VarRefExpr(newvd), getItems));
newExpr = Builder.ArrayIndex(Builder.VarRefExpr(newvd), innerIndex);
rhsExpr = getItems;
}
}
}
// does the expression have the form array[indices[k]][indices2[k]]?
if (newvd == null && UseGetItems && iaie.Indices.Count == 1)
{
if (iaie.Target is IArrayIndexerExpression target &&
iaie.Indices[0] is IArrayIndexerExpression index2 &&
index2.Indices.Count == 1 &&
index2.Indices[0] is IVariableReferenceExpression innerIndex &&
target.Indices.Count == 1 &&
target.Indices[0] is IArrayIndexerExpression index)
{
IForStatement innerLoop = Recognizer.GetLoopForVariable(context, innerIndex);
if (index.Indices.Count == 1 &&
index.Indices[0].Equals(innerIndex) &&
innerLoop != null &&
AreLoopsDisjoint(innerLoop, target.Target, index.Target))
{
// expression has the form array[indices[k]][indices2[k]]
if (isDef)
{
Error("fancy indexing not allowed on left hand side");
return(iaie);
}
var innerLoops = new List <IForStatement>();
innerLoops.Add(innerLoop);
var indexTarget = index.Target;
var index2Target = index2.Target;
// check if the index array is jagged, i.e. array[indices[k][j]]
while (indexTarget is IArrayIndexerExpression indexTargetExpr &&
index2Target is IArrayIndexerExpression index2TargetExpr)
{
if (indexTargetExpr.Indices.Count == 1 &&
indexTargetExpr.Indices[0] is IVariableReferenceExpression innerIndexTarget &&
index2TargetExpr.Indices.Count == 1 &&
index2TargetExpr.Indices[0] is IVariableReferenceExpression innerIndex2Target)
{
IForStatement indexTargetLoop = Recognizer.GetLoopForVariable(context, innerIndexTarget);
if (indexTargetLoop != null &&
AreLoopsDisjoint(indexTargetLoop, target.Target, indexTargetExpr.Target) &&
innerIndexTarget.Equals(innerIndex2Target))
{
innerLoops.Add(indexTargetLoop);
indexTarget = indexTargetExpr.Target;
index2Target = index2TargetExpr.Target;
}
else
{
break;
}
}
else
{
break;
}
}
WarnIfLocal(indexTarget, target.Target, iaie);
WarnIfLocal(index2Target, target.Target, iaie);
innerLoops.Reverse();
var loopSizes = innerLoops.ListSelect(ifs => new[] { Recognizer.LoopSizeExpression(ifs) });
var newIndexVars = innerLoops.ListSelect(ifs => new[] { Recognizer.LoopVariable(ifs) });
// Build name of replacement variable from index values
StringBuilder sb = new StringBuilder("_item");
AppendIndexString(sb, target);
AppendIndexString(sb, iaie);
string name = ToString(target.Target) + sb.ToString();
VariableInformation varInfo = VariableInformation.GetVariableInformation(context, baseVar);
var indices = Recognizer.GetIndices(iaie);
newvd = varInfo.DeriveArrayVariable(stmts, context, name, loopSizes, newIndexVars, indices);
if (!context.InputAttributes.Has <DerivedVariable>(newvd))
{
context.InputAttributes.Set(newvd, new DerivedVariable());
}
IExpression getItems;
if (innerLoops.Count == 1)
{
getItems = Builder.StaticGenericMethod(new Func <IReadOnlyList <IReadOnlyList <PlaceHolder> >, IReadOnlyList <int>, IReadOnlyList <int>, PlaceHolder[]>(Collection.GetItemsFromJagged),
new Type[] { tp }, target.Target, indexTarget, index2Target);
}
else if (innerLoops.Count == 2)
{
getItems = Builder.StaticGenericMethod(new Func <IReadOnlyList <IReadOnlyList <PlaceHolder> >, IReadOnlyList <IReadOnlyList <int> >, IReadOnlyList <IReadOnlyList <int> >, PlaceHolder[][]>(Collection.GetJaggedItemsFromJagged),
new Type[] { tp }, target.Target, indexTarget, index2Target);
}
else
{
throw new NotImplementedException($"innerLoops.Count = {innerLoops.Count}");
}
context.InputAttributes.CopyObjectAttributesTo <Algorithm>(baseVar, context.OutputAttributes, getItems);
stmts.Add(Builder.AssignStmt(Builder.VarRefExpr(newvd), getItems));
var newIndices = newIndexVars.ListSelect(ivds => Util.ArrayInit(ivds.Length, i => Builder.VarRefExpr(ivds[i])));
newExpr = Builder.JaggedArrayIndex(Builder.VarRefExpr(newvd), newIndices);
rhsExpr = getItems;
}
else if (HasAnyCommonLoops(index, index2))
{
Warning($"This model will consume excess memory due to the indexing expression {iaie} since {index} and {index2} have larger depth than the compiler can handle.");
}
}
