public ItemUse(Text.Span p, VarLikeConstructUse /*!*/ array, Expression index, bool functionArrayDereferencing = false)
: base(p)
{
Debug.Assert(array != null);
this.array = array;
this.index = index;
this.functionArrayDereferencing = functionArrayDereferencing;
}
public ItemUse(Position p, VarLikeConstructUse/*!*/ array, Expression index, bool functionArrayDereferencing = false)
: base(p)
{
Debug.Assert(array != null);
this.array = array;
this.index = index;
this.functionArrayDereferencing = functionArrayDereferencing;
}
virtual public void VisitVarLikeConstructUse(VarLikeConstructUse x)
{
VisitElement(x.IsMemberOf);
}
/// <summary>
/// Emits IL instructions that ensure that the specified property of an object is
/// of the <see cref="PhpArray"/> type.
/// </summary>
/// <param name="varObject">Represents the instance whose property should be examined.</param>
/// <param name="fieldName">A <see cref="SimpleVarUse"/> that evaluates to the property name.</param>
/// <param name="ensureArray">Whether to ensure that static property is an array (or an object).</param>
/// <remarks>Nothing is expected on the evaluation stack. If the property is of <see cref="PhpArray"/> type
/// it is left on the evaluation stack. Otherwise the control is transfered to the end of chain.</remarks>
public PhpTypeCode EmitEnsureProperty(VarLikeConstructUse/*!*/ varObject, SimpleVarUse/*!*/ fieldName, bool ensureArray)
{
// Template: PhpArray EnsurePropertyIsArray(DObject,field,DTypeDesc)
Debug.Assert(varObject != null && fieldName != null);
Debug.Assert(fieldName is DirectVarUse || fieldName is IndirectVarUse);
LocationTypes location;
DProperty property = ResolveProperty(varObject, fieldName, out location);
ILEmitter il = codeGenerator.IL;
PhpField php_field = property as PhpField;
if (php_field != null) // we can emit code that manipulates the property directly
{
// HACK HACK
EmitEnsurePhpFieldDirect(php_field, fieldName, ensureArray);
}
else
{
switch (location)
{
case LocationTypes.GlobalCode:
{
// call EnsurePropertyIsArray
codeGenerator.EmitLoadSelf();
fieldName.EmitName(codeGenerator);
codeGenerator.EmitLoadClassContext();
if (ensureArray)
{
il.Emit(OpCodes.Call, Methods.Operators.EnsurePropertyIsArray);
}
else
{
codeGenerator.EmitLoadScriptContext();
il.Emit(OpCodes.Call, Methods.Operators.EnsurePropertyIsObject);
}
break;
}
case LocationTypes.MethodDecl:
{
if (ensureArray) this.Lengthen(); // for hop over ->
FunctionCall func = varObject as FunctionCall;
if (func == null)
{
varObject.Emit(codeGenerator);
}
else
{
this.LoadAddressOfFunctionReturnValue = true;
func.Emit(codeGenerator);
RecastValueReturnedByFunctionCall();
}
fieldName.EmitName(codeGenerator);
codeGenerator.EmitLoadClassContext();
if (ensureArray)
{
il.Emit(OpCodes.Call, Methods.Operators.EnsurePropertyIsArray);
}
else
{
codeGenerator.EmitLoadScriptContext();
il.Emit(OpCodes.Call, Methods.Operators.EnsurePropertyIsObject);
}
EmitErrorCheck(ensureArray);
break;
}
// if the location was FunctionDecl, appropriate code was already generated by GetDProperty
}
}
return (ensureArray ? PhpTypeCode.PhpArray : PhpTypeCode.DObject);
}
/// <summary>
/// Gets the <see cref="ObjectFieldLazyEmitInfo"/> object stored in collection.
/// </summary>
/// <param name="var_object"></param>
/// <param name="old_IsArrayItem"></param>
/// <param name="old_IsLastMember"></param>
/// <returns></returns>
/// <remarks>
/// This method should only be called from <see cref="ChainBuilder.GetObjectForLazyEmit"/> method.
/// </remarks>
public ObjectFieldLazyEmitInfo GetItem(VarLikeConstructUse var_object, bool old_IsArrayItem, bool old_IsLastMember)
{
if (stack.Count != 0)
{
ObjectFieldLazyEmitInfo info = (ObjectFieldLazyEmitInfo)stack.Pop();
Debug.Assert(info != null);
info.ObjectForLazyEmit = var_object;
info.Old_IsArrayItem = old_IsArrayItem;
info.Old_IsLastMember = old_IsLastMember;
}
return new ObjectFieldLazyEmitInfo(var_object, old_IsArrayItem, old_IsLastMember);
}
public void Reset()
{
objectForLazyEmit = null;
}
public ObjectFieldLazyEmitInfo(VarLikeConstructUse var_object, bool old_IsArrayItem, bool old_IsLastMember)
{
this.objectForLazyEmit = var_object;
this.Old_IsArrayItem = old_IsArrayItem;
this.Old_IsLastMember = old_IsLastMember;
}
/// <summary>
/// Tries to find an instance of <see cref="DProperty"/> that corresponds to an instance property given by
/// <paramref name="varObject"/> and <paramref name="fieldName"/>. Currently it is possible only if
/// <paramref name="varObject"/> represents <B>$this</B> and <paramref name="fieldName"/> is a compile time
/// known instance property, which is surely accessible from current location.
/// </summary>
/// <param name="varObject">Represents the left side of <B>-></B>.</param>
/// <param name="fieldName">Represents the right side of <B>-></B>.</param>
/// <param name="location">Current location, valid only if the return value is <B>null</B>. Used by the caller to
/// decide what kind of run time access should be emitted.</param>
/// <returns>A valid non-<B>null</B> <see cref="PhpField"/> if the field was found, <B>null</B> otherwise.</returns>
internal DProperty ResolveProperty(VarLikeConstructUse varObject, SimpleVarUse fieldName, out LocationTypes location)
{
DirectVarUse direct_var = varObject as DirectVarUse;
DirectVarUse direct_field_name;
if (direct_var != null && (direct_field_name = fieldName as DirectVarUse) != null &&
direct_var.IsMemberOf == null && direct_var.VarName.IsThisVariableName)
{
ILEmitter il = codeGenerator.IL;
location = codeGenerator.LocationStack.LocationType;
switch (location)
{
case LocationTypes.GlobalCode:
{
// load $this from one of Main's arguments and check for null
Label this_non_null = il.DefineLabel();
codeGenerator.EmitLoadSelf();
il.Emit(OpCodes.Brtrue_S, this_non_null);
codeGenerator.EmitPhpException(Methods.PhpException.ThisUsedOutOfObjectContext);
il.Emit(OpCodes.Br, TopChain.ErrorLabel);
il.MarkLabel(this_non_null, true);
return null;
}
case LocationTypes.FunctionDecl:
{
// always throws error
codeGenerator.EmitPhpException(Methods.PhpException.ThisUsedOutOfObjectContext);
il.Emit(OpCodes.Br, TopChain.ErrorLabel);
return null;
}
case LocationTypes.MethodDecl:
{
CompilerLocationStack.MethodDeclContext context = codeGenerator.LocationStack.PeekMethodDecl();
if (context.Method.IsStatic)
{
// always throws error
codeGenerator.EmitPhpException(Methods.PhpException.ThisUsedOutOfObjectContext);
il.Emit(OpCodes.Br, TopChain.ErrorLabel);
location = LocationTypes.FunctionDecl;
return null;
}
else
{
DProperty property;
if (context.Type.GetProperty(direct_field_name.VarName, context.Type, out property)
== GetMemberResult.OK && !property.IsStatic)
{
return property;
}
}
break;
}
}
}
location = LocationTypes.MethodDecl;
return null;
}
virtual public void VisitVarLikeConstructUse(VarLikeConstructUse x)
{
VisitElement(x.IsMemberOf);
}
