public virtual void BuildAxisClosureSequence(Expression source, AxisBuildState state, SequenceAccessor sqa, Block block, BlockScope scope) {
if (!this.IsLocal(source)) {
Expression loc = this.NewClosureLocal(source.Type, scope);
block.Statements.Add(new AssignmentStatement(loc, source));
source = loc;
}
foreach( Accessor acc in sqa.Accessors ) {
block.Statements.Add(this.BuildAxisClosureBlock(source, state, acc, scope));
}
}
public virtual void BuildAxisClosureUnion(Expression source, AxisBuildState state, SwitchAccessor swa, bool yieldResult, Block block, BlockScope scope) {
TypeUnion tu = source.Type as TypeUnion;
Debug.Assert(tu != null, "Switch accessor must have type union");
if (!this.IsLocal(source)) {
Expression loc = this.NewClosureLocal(source.Type, scope);
block.Statements.Add(new AssignmentStatement(loc, source));
source = loc;
}
// determine type union tag and value
Method mgetvalue = this.GetTypeView(tu).GetMethod(StandardIds.GetValue);
MethodCall mcgetvalue = new MethodCall(new MemberBinding(source, mgetvalue), null);
mcgetvalue.Type = mgetvalue.ReturnType;
Local locValue = new Local(SystemTypes.Object);
block.Statements.Add(new AssignmentStatement(locValue, mcgetvalue));
Method mgettag = this.GetTypeView(tu).GetMethod(StandardIds.GetTag);
MethodCall mcgettag = new MethodCall(new MemberBinding(source, mgettag), null);
mcgettag.Type = mgettag.ReturnType;
Local locTag = new Local(SystemTypes.UInt32);
block.Statements.Add(new AssignmentStatement(locTag, mcgettag));
// switch on type union tag
BlockList blocks = new BlockList(swa.Accessors.Count);
Block endBlock = new Block(null);
foreach( int id in swa.Accessors.Keys ) {
Accessor acc = (Accessor) swa.Accessors[id];
Block caseBlock = new Block(new StatementList(3));
blocks.Add(caseBlock);
block.Statements.Add(new Branch(new BinaryExpression(locTag, new Literal(id, SystemTypes.Int32), NodeType.Eq), caseBlock));
Expression locvar = this.NewClosureLocal(swa.Type.Types[id], scope);
caseBlock.Statements.Add(new AssignmentStatement(locvar, this.Unbox(locValue, locvar.Type)));
this.BuildAxisClosureExpression(locvar, state, acc, yieldResult, caseBlock, scope);
caseBlock.Statements.Add(new Branch(null, endBlock));
}
block.Statements.Add(new Branch(null, endBlock));
for( int i = 0, n = blocks.Count; i < n; i++ ) {
block.Statements.Add(blocks[i]);
}
block.Statements.Add(endBlock);
}
public virtual void BuildAxisClosureExpression(Expression source, AxisBuildState state, Accessor next, bool yieldResult, Block inner, BlockScope scope) {
Cardinality tcard = this.typeSystem.GetCardinality(state.YieldType, this.TypeViewer);
Cardinality scard = this.typeSystem.GetCardinality(source, this.TypeViewer);
// lift over collections
while (true) {
if (this.typeSystem.IsStructural(source.Type))
goto lift_done;
if (yieldResult && scard == tcard)
goto lift_done;
switch (scard) {
case Cardinality.ZeroOrOne:
Block b = new Block(new StatementList(3));
inner.Statements.Add(this.IfNotNull(source, b));
inner = b;
source = this.GetNonNull(source, inner, scope);
break;
case Cardinality.ZeroOrMore:
case Cardinality.OneOrMore:
TypeNode elementType = this.typeSystem.GetStreamElementType(source, this.TypeViewer);
Expression target = null;
Block newInner = null;
inner.Statements.Add(this.BuildClosureForEach(source, ref target, out newInner, scope));
inner = newInner;
source = target;
break;
default:
goto lift_done;
}
scard = this.typeSystem.GetCardinality(source, this.TypeViewer);
}
lift_done:
if (yieldResult) {
if (scard == Cardinality.None) {
Block b = new Block(new StatementList(1));
inner.Statements.Add(this.IfNotNull(source, b));
inner = b;
source = this.GetNonNull(source, inner, scope);
}
if (state.YieldTarget != null && state.YieldBlock != null) {
inner.Statements.Add(new AssignmentStatement(state.YieldTarget, this.typeSystem.ExplicitCoercion(source, state.YieldType, this.TypeViewer)));
inner.Statements.Add(new Branch(Literal.True, state.YieldBlock));
}
else {
inner.Statements.Add(new Yield(this.typeSystem.ExplicitCoercion(source, state.YieldType, this.TypeViewer)));
}
}
if (next != null) {
inner.Statements.Add(this.BuildAxisClosure(source, state, next, scope));
}
}
public virtual void BuildAxisClosureMember(Expression source, AxisBuildState state, MemberAccessor ma, Block block, BlockScope scope) {
Block inner = block;
bool isStatic = (source is Literal) && (source.Type == SystemTypes.Type);
if (!this.IsLocal(source)) {
Expression loc = this.NewClosureLocal(source.Type, scope);
inner.Statements.Add(new AssignmentStatement(loc, source));
source = loc;
}
// sanity check for member/type mismatch caused by aliases
if (!isStatic && source.Type != ma.Member.DeclaringType) {
Expression loc = this.NewClosureLocal(ma.Member.DeclaringType, scope);
inner.Statements.Add(new AssignmentStatement(loc, this.typeSystem.ExplicitCoercion(source, loc.Type, this.TypeViewer)));
source = loc;
}
Cardinality tcard = this.typeSystem.GetCardinality(state.YieldType, this.TypeViewer);
Cardinality scard = this.typeSystem.GetCardinality(source, this.TypeViewer);
if (scard != Cardinality.One) {
Block b = new Block(new StatementList(3));
inner.Statements.Add(this.IfNotNull(source, b));
inner = b;
source = this.GetNonNull(source, inner, scope);
}
TypeNode memberType = this.typeSystem.GetMemberType(ma.Member);
MemberBinding mb = null;
if (isStatic) {
mb = new MemberBinding(null, ma.Member);
}
else {
mb = new MemberBinding(source, ma.Member);
}
mb.Type = memberType;
this.BuildAxisClosureExpression(mb, state, ma.Next, ma.Yield, inner, scope);
}
public virtual Block BuildAxisClosureBlock(Expression source, AxisBuildState state, Accessor accessor, BlockScope scope) {
if (accessor == null || source == null || state == null || state.YieldType == null || scope == null)
return null;
MemberAccessor ma = accessor as MemberAccessor;
if (ma != null) {
Block block = new Block(new StatementList(3));
this.BuildAxisClosureMember(source, state, ma, block, scope);
return block;
}
SequenceAccessor sqa = accessor as SequenceAccessor;
if (sqa != null) {
Block block = new Block(new StatementList(sqa.Accessors.Count + 1));
this.BuildAxisClosureSequence(source, state, sqa, block, scope);
return block;
}
SwitchAccessor swa = accessor as SwitchAccessor;
if (swa != null) {
Block block = new Block(new StatementList());
this.BuildAxisClosureUnion(source, state, swa, false, block, scope);
return block;
}
// todo: add error message here
return null;
}
public virtual Block BuildAxisClosure(Expression source, AxisBuildState state, Accessor acc, BlockScope scope) {
if (state.TypeClosures != null) {
TypeNode tn = source.Type;
CurrentClosure cc = (CurrentClosure) state.TypeClosures[tn.UniqueKey];
if (cc == null) {
cc = this.BeginCurrentClosure(state.YieldType, "axis");
Parameter p = new Parameter(Identifier.For("source"), tn);
cc.Method.Parameters = new ParameterList(1);
cc.Method.Parameters.Add(p);
state.TypeClosures[tn.UniqueKey] = cc;
ParameterField pf = new ParameterField(cc.Method.Scope, null, FieldFlags.Public, p.Name, p.Type, null);
pf.Parameter = p;
cc.Method.Scope.Members.Add(pf);
MemberBinding mb = new MemberBinding(new ImplicitThis(), pf);
mb.Type = pf.Type;
cc.Method.Body.Statements.Add(this.BuildAxisClosureBlock(mb, state, acc, cc.Method.Body.Scope));
this.EndCurrentClosure(cc);
}
Block block = new Block(new StatementList(1));
ImplicitThis it = new ImplicitThis();
it.Type = cc.Method.DeclaringType;
MethodCall mc = new MethodCall(new MemberBinding(it, cc.Method), new ExpressionList(source));
mc.Type = cc.Method.ReturnType;
if (cc.Method.IsVirtual) mc.NodeType = NodeType.Callvirt;
Expression target = null;
Block inner = null;
block.Statements.Add(this.BuildClosureForEach(mc, ref target, out inner, scope));
inner.Statements.Add(new Yield(target));
return block;
}
return this.BuildAxisClosureBlock(source, state, acc, scope);
}
public override Node VisitQueryAxis(QueryAxis axis) {
if (axis.Type == null) return null; // error handling.
Cardinality tcard = this.typeSystem.GetCardinality(axis, this.TypeViewer);
switch( tcard ) {
case Cardinality.None:
case Cardinality.One:
case Cardinality.ZeroOrOne: {
BlockScope scope = this.currentMethod.Body.Scope;
Block block = new Block(new StatementList(4));
AxisBuildState state = new AxisBuildState(axis.Type);
state.YieldBlock = new Block();
state.YieldTarget = this.NewClosureLocal(axis.Type, scope);
if (tcard == Cardinality.ZeroOrOne) {
block.Statements.Add(new AssignmentStatement(state.YieldTarget, this.typeSystem.ImplicitCoercion(Literal.Null, state.YieldType, this.TypeViewer)));
}
block.Statements.Add(this.BuildAxisClosure(axis.Source, state, axis.AccessPlan, scope));
block.Statements.Add(state.YieldBlock);
block.Statements.Add(new ExpressionStatement(state.YieldTarget));
BlockExpression be = new BlockExpression(block, state.YieldType);
return this.VisitBlockExpression(be);
}
default:
case Cardinality.OneOrMore:
case Cardinality.ZeroOrMore: {
TypeNode targetType = this.typeSystem.GetStreamElementType(axis, this.TypeViewer);
Block body = null;
Node closure = this.StartQueryClosure(targetType, "axis", out body);
BlockScope scope = body.Scope;
AxisBuildState state = new AxisBuildState(targetType);
if (axis.IsCyclic) state.TypeClosures = new Hashtable();
Cardinality scard = this.typeSystem.GetCardinality(axis.Source, this.TypeViewer);
switch( scard ) {
case Cardinality.None:
case Cardinality.One:
case Cardinality.ZeroOrOne:
body.Statements.Add(this.BuildAxisClosure(axis.Source, state, axis.AccessPlan, scope));
break;
case Cardinality.OneOrMore:
case Cardinality.ZeroOrMore:
Expression feTarget = null;
Block inner = null;
body.Statements.Add(this.BuildClosureForEach(axis.Source, ref feTarget, out inner, scope));
inner.Statements.Add(this.BuildAxisClosure(feTarget, state, axis.AccessPlan, scope));
break;
}
return this.EndQueryClosure(closure, axis.Type);
}
}
}
