if ((FalseStatement != null) &&
!FalseStatement.Resolve (ec))
- return false;
- }
+ return false;
+ }
return true;
}
if (!Statement.Resolve (ec))
ok = false;
- ec.CurrentBranching.Infinite = infinite;
- ec.EndFlowBranching ();
+ ec.CurrentBranching.Infinite = infinite;
+ ec.EndFlowBranching ();
return ok;
}
public override bool Resolve (EmitContext ec)
{
+ AnonymousContainer am = ec.CurrentAnonymousMethod;
+ if ((am != null) && am.IsIterator && ec.InIterator) {
+ Report.Error (1622, loc, "Cannot return a value from iterators. Use the yield return " +
+ "statement to return a value, or yield break to end the iteration");
+ return false;
+ }
+
if (ec.ReturnType == null){
- if (Expr != null){
+ if (Expr != null){
if (ec.CurrentAnonymousMethod != null){
Report.Error (1662, loc, String.Format (
"Anonymous method could not be converted to delegate " +
return false;
}
- if (ec.InIterator) {
- Report.Error (1622, loc, "Cannot return a value from iterators. Use the yield return " +
- "statement to return a value, or yield break to end the iteration");
- return false;
- }
-
Expr = Expr.Resolve (ec);
if (Expr == null)
return false;
}
}
- if (ec.InIterator){
- Error (-206, "Return statement not allowed inside iterators");
- return false;
- }
-
FlowBranching.UsageVector vector = ec.CurrentBranching.CurrentUsageVector;
if (ec.CurrentBranching.InTryOrCatch (true)) {
}
Type t = expr.Type;
-
+
if ((t != TypeManager.exception_type) &&
- !t.IsSubclassOf (TypeManager.exception_type) &&
- !(expr is NullLiteral)) {
+ !TypeManager.IsSubclassOf (t, TypeManager.exception_type) &&
+ !(expr is NullLiteral)) {
Error (155,
"The type caught or thrown must be derived " +
"from System.Exception");
} else if (ec.CurrentBranching.InTryOrCatch (false))
ec.CurrentBranching.AddFinallyVector (
ec.CurrentBranching.CurrentUsageVector);
- else if (ec.CurrentBranching.InLoop ())
+ else if (ec.CurrentBranching.InLoop () || ec.CurrentBranching.InSwitch ())
ec.CurrentBranching.AddBreakVector (
ec.CurrentBranching.CurrentUsageVector);
Pinned = 4,
IsThis = 8,
Captured = 16,
- AddressTaken = 32
+ AddressTaken = 32,
+ CompilerGenerated = 64
}
- Flags flags;
+ public enum ReadOnlyContext: byte {
+ Using,
+ Foreach,
+ Fixed
+ }
+ Flags flags;
+ ReadOnlyContext ro_context;
+
public LocalInfo (Expression type, string name, Block block, Location l)
{
Type = type;
}
}
+ public bool CompilerGenerated {
+ get {
+ return (flags & Flags.CompilerGenerated) != 0;
+ }
+
+ set {
+ flags |= Flags.CompilerGenerated;
+ }
+ }
+
public override string ToString ()
{
return String.Format ("LocalInfo ({0},{1},{2},{3})",
get {
return (flags & Flags.ReadOnly) != 0;
}
- set {
- flags = value ? (flags | Flags.ReadOnly) : (unchecked (flags & ~Flags.ReadOnly));
+ }
+
+ public void SetReadOnlyContext (ReadOnlyContext context)
+ {
+ flags |= Flags.ReadOnly;
+ ro_context = context;
+ }
+
+ public string GetReadOnlyContext ()
+ {
+ if (!ReadOnly)
+ throw new InternalErrorException ("Variable is not readonly");
+
+ switch (ro_context) {
+ case ReadOnlyContext.Fixed:
+ return "fixed variable";
+ case ReadOnlyContext.Foreach:
+ return "foreach iteration variable";
+ case ReadOnlyContext.Using:
+ return "using variable";
}
+ throw new NotImplementedException ();
}
//
// statements.
//
ArrayList children;
-
+
//
// Labels. (label, block) pairs.
//
//
// Keeps track of constants
Hashtable constants;
+
+ //
+ // Temporary variables.
+ //
+ ArrayList temporary_variables;
//
// If this is a switch section, the enclosing switch block.
int idx;
Parameter p = Toplevel.Parameters.GetParameterByName (name, out idx);
if (p != null) {
- Report.SymbolRelatedToPreviousError (Toplevel.Parameters.Location, name);
+ Report.SymbolRelatedToPreviousError (p.Location, name);
Report.Error (136, l, "'{0}' hides a method parameter", name);
return null;
}
return true;
}
+ static int next_temp_id = 0;
+
+ public LocalInfo AddTemporaryVariable (TypeExpr te, Location loc)
+ {
+ if (temporary_variables == null)
+ temporary_variables = new ArrayList ();
+
+ int id = ++next_temp_id;
+ string name = "$s_" + id.ToString ();
+
+ LocalInfo li = new LocalInfo (te, name, this, loc);
+ li.CompilerGenerated = true;
+ temporary_variables.Add (li);
+ return li;
+ }
+
public Hashtable Variables {
get {
return variables;
return e != null;
}
- //
- // Returns a `ParameterReference' for the given name, or null if there
- // is no such parameter
- //
- public ParameterReference GetParameterReference (string name, Location loc)
- {
- Parameter par;
- int idx;
-
- for (Block b = this; b != null; b = b.Toplevel.Parent) {
- Parameters pars = b.Toplevel.Parameters;
- par = pars.GetParameterByName (name, out idx);
- if (par != null)
- return new ParameterReference (pars, this, idx, name, loc);
- }
- return null;
- }
-
- //
- // Whether the parameter named `name' is local to this block,
- // or false, if the parameter belongs to an encompassing block.
- //
- public bool IsLocalParameter (string name)
- {
- return Toplevel.Parameters.GetParameterByName (name) != null;
- }
-
- //
- // Whether the `name' is a parameter reference
- //
- public bool IsParameterReference (string name)
- {
- Parameter par;
- int idx;
-
- for (Block b = this; b != null; b = b.Toplevel.Parent) {
- par = b.Toplevel.Parameters.GetParameterByName (name, out idx);
- if (par != null)
- return true;
- }
- return false;
- }
-
/// <returns>
/// A list of labels that were not used within this block
/// </returns>
continue;
}
-#if false
- if (remap_locals)
- vi.FieldBuilder = ec.MapVariable (name, vi.VariableType);
- else if (vi.Pinned)
- //
- // This is needed to compile on both .NET 1.x and .NET 2.x
- // the later introduced `DeclareLocal (Type t, bool pinned)'
- //
- vi.LocalBuilder = TypeManager.DeclareLocalPinned (ig, vi.VariableType);
- else if (!vi.IsThis)
- vi.LocalBuilder = ig.DeclareLocal (vi.VariableType);
-#endif
-
if (constants == null)
continue;
ec.CurrentBlock = this;
Expression e = cv.Resolve (ec);
- if (e == null)
- continue;
Constant ce = e as Constant;
if (ce == null){
Report.Error (133, vi.Location,
- "The expression being assigned to `" +
- name + "' must be constant (" + e + ")");
+ "The expression being assigned to '{0}' must be constant", name);
continue;
}
if (variables != null){
bool have_captured_vars = ec.HaveCapturedVariables ();
- bool remap_locals = ec.RemapToProxy;
foreach (DictionaryEntry de in variables){
LocalInfo vi = (LocalInfo) de.Value;
if (have_captured_vars && ec.IsCaptured (vi))
continue;
- if (remap_locals){
- vi.FieldBuilder = ec.MapVariable (vi.Name, vi.VariableType);
- } else {
- if (vi.Pinned)
- //
- // This is needed to compile on both .NET 1.x and .NET 2.x
- // the later introduced `DeclareLocal (Type t, bool pinned)'
- //
- vi.LocalBuilder = TypeManager.DeclareLocalPinned (ig, vi.VariableType);
- else if (!vi.IsThis)
- vi.LocalBuilder = ig.DeclareLocal (vi.VariableType);
- }
+ if (vi.Pinned)
+ //
+ // This is needed to compile on both .NET 1.x and .NET 2.x
+ // the later introduced `DeclareLocal (Type t, bool pinned)'
+ //
+ vi.LocalBuilder = TypeManager.DeclareLocalPinned (ig, vi.VariableType);
+ else if (!vi.IsThis)
+ vi.LocalBuilder = ig.DeclareLocal (vi.VariableType);
+ }
+ }
+
+ if (temporary_variables != null) {
+ AnonymousContainer am = ec.CurrentAnonymousMethod;
+ TypeBuilder scope = null;
+ if ((am != null) && am.IsIterator) {
+ scope = am.Scope.ScopeTypeBuilder;
+ if (scope == null)
+ throw new InternalErrorException ();
+ }
+ foreach (LocalInfo vi in temporary_variables) {
+ if (scope != null) {
+ if (vi.FieldBuilder == null)
+ vi.FieldBuilder = scope.DefineField (
+ vi.Name, vi.VariableType, FieldAttributes.Assembly);
+ } else
+ vi.LocalBuilder = ig.DeclareLocal (vi.VariableType);
}
}
}
bool unreachable_shown;
+ bool unreachable;
public override bool Resolve (EmitContext ec)
{
// from the beginning of the function. The outer Resolve() that detected the unreachability is
// responsible for handling the situation.
//
- bool unreachable = false;
-
int statement_count = statements.Count;
for (int ix = 0; ix < statement_count; ix++){
Statement s = (Statement) statements [ix];
-
- if (unreachable && !(s is LabeledStatement)) {
- if (s == EmptyStatement.Value)
- s.loc = EndLocation;
- if (!s.ResolveUnreachable (ec, !unreachable_shown))
- ok = false;
+ if (unreachable) {
+ if (s is Block)
+ ((Block) s).unreachable = true;
- if (s != EmptyStatement.Value)
+ if (!unreachable_shown && (RootContext.WarningLevel >= 2)) {
+ Report.Warning (
+ 162, loc, "Unreachable code detected");
unreachable_shown = true;
- else
- s.loc = Location.Null;
-
- if (ok && !(s is Block)) {
- statements [ix] = EmptyStatement.Value;
- continue;
}
}
- if (s.Resolve (ec) == false) {
- ok = false;
+ if (!s.Resolve (ec)) {
+ ok = false;
statements [ix] = EmptyStatement.Value;
continue;
}
- num_statements = ix + 1;
+ if (unreachable && !(s is LabeledStatement) && !(s is Block))
+ statements [ix] = EmptyStatement.Value;
+ num_statements = ix + 1;
if (s is LabeledStatement)
unreachable = false;
else
Report.Debug (4, "RESOLVE BLOCK DONE", StartLocation,
ec.CurrentBranching, statement_count, num_statements);
-
FlowBranching.UsageVector vector = ec.DoEndFlowBranching ();
ec.CurrentBlock = prev_block;
public override bool ResolveUnreachable (EmitContext ec, bool warn)
{
unreachable_shown = true;
+ unreachable = true;
if (warn && (RootContext.WarningLevel >= 2))
Report.Warning (162, loc, "Unreachable code detected");
- if (Implicit)
- return Resolve (ec);
-
ec.StartFlowBranching (FlowBranching.BranchingType.Block, loc);
bool ok = Resolve (ec);
ec.KillFlowBranching ();
// Pointer to the host of this anonymous method, or null
// if we are the topmost block
//
- public ToplevelBlock Container;
+ ToplevelBlock container;
CaptureContext capture_context;
FlowBranching top_level_branching;
Hashtable capture_contexts;
+ ArrayList children;
//
// The parameters for the block.
cc.AdjustScopes ();
}
}
-
+
public CaptureContext ToplevelBlockCaptureContext {
get {
return capture_context;
}
}
-
+
+ public ToplevelBlock Container {
+ get {
+ return container;
+ }
+ }
+
+ protected void AddChild (ToplevelBlock block)
+ {
+ if (children == null)
+ children = new ArrayList ();
+
+ children.Add (block);
+ }
+
//
// Parent is only used by anonymous blocks to link back to their
// parents
base (null, flags | Flags.IsToplevel, start, Location.Null)
{
Parameters = parameters == null ? Parameters.EmptyReadOnlyParameters : parameters;
- Container = container;
+ this.container = container;
+
+ if (container != null)
+ container.AddChild (this);
}
public ToplevelBlock (Location loc) : this (null, (Flags) 0, null, loc)
{
}
- public void SetHaveAnonymousMethods (Location loc, AnonymousMethod host)
+ public void SetHaveAnonymousMethods (Location loc, AnonymousContainer host)
{
if (capture_context == null)
capture_context = new CaptureContext (this, loc, host);
}
}
+ //
+ // This is used if anonymous methods are used inside an iterator
+ // (see 2test-22.cs for an example).
+ //
+ // The AnonymousMethod is created while parsing - at a time when we don't
+ // know yet that we're inside an iterator, so it's `Container' is initially
+ // null. Later on, when resolving the iterator, we need to move the
+ // anonymous method into that iterator.
+ //
+ public void ReParent (ToplevelBlock new_parent, AnonymousContainer new_host)
+ {
+ foreach (ToplevelBlock block in children) {
+ if (block.CaptureContext == null)
+ continue;
+
+ block.container = new_parent;
+ block.CaptureContext.ReParent (new_parent, new_host);
+ }
+ }
+
+ //
+ // Returns a `ParameterReference' for the given name, or null if there
+ // is no such parameter
+ //
+ public ParameterReference GetParameterReference (string name, Location loc)
+ {
+ Parameter par;
+ int idx;
+
+ for (ToplevelBlock t = this; t != null; t = t.Container) {
+ Parameters pars = t.Parameters;
+ par = pars.GetParameterByName (name, out idx);
+ if (par != null)
+ return new ParameterReference (pars, this, idx, name, loc);
+ }
+ return null;
+ }
+
+ //
+ // Whether the parameter named `name' is local to this block,
+ // or false, if the parameter belongs to an encompassing block.
+ //
+ public bool IsLocalParameter (string name)
+ {
+ return Parameters.GetParameterByName (name) != null;
+ }
+
+ //
+ // Whether the `name' is a parameter reference
+ //
+ public bool IsParameterReference (string name)
+ {
+ for (ToplevelBlock t = this; t != null; t = t.Container) {
+ if (t.IsLocalParameter (name))
+ return true;
+ }
+ return false;
+ }
+
public bool ResolveMeta (EmitContext ec, InternalParameters ip)
{
int errors = Report.Errors;
{
if (emit_finally)
ec.ig.BeginFinallyBlock ();
- else
+ else if (ec.InIterator)
ec.CurrentIterator.MarkFinally (ec, parent_vectors);
EmitFinally (ec);
}
CheckObsolete (expr_type);
- if (ec.RemapToProxy){
- Report.Error (-210, loc, "Fixed statement not allowed in iterators");
- return false;
- }
-
data = new Emitter [declarators.Count];
if (!expr_type.IsPointer){
Expression e = (Expression) p.Second;
vi.VariableInfo.SetAssigned (ec);
- vi.ReadOnly = true;
+ vi.SetReadOnlyContext (LocalInfo.ReadOnlyContext.Fixed);
//
// The rules for the possible declarators are pretty wise,
if (!Fini.Resolve (ec))
ok = false;
ec.InFinally = was_finally;
+
+ if (!ec.InIterator)
+ need_exc_block = true;
}
- ResolveFinally (branching);
- need_exc_block |= emit_finally;
+ if (ec.InIterator) {
+ ResolveFinally (branching);
+ need_exc_block |= emit_finally;
+ } else
+ emit_finally = Fini != null;
FlowBranching.Reachability reachability = ec.EndFlowBranching ();
public override void EmitFinally (EmitContext ec)
{
- if (Fini != null){
+ if (Fini != null)
Fini.Emit (ec);
- }
}
public bool HasCatch
/// <summary>
/// Implementation of the foreach C# statement
/// </summary>
- public class Foreach : ExceptionStatement {
+ public class Foreach : Statement {
Expression type;
Expression variable;
Expression expr;
Statement statement;
- ForeachHelperMethods hm;
- Expression empty, conv;
- Type array_type, element_type;
- Type var_type;
- VariableStorage enumerator;
ArrayForeach array;
+ CollectionForeach collection;
public Foreach (Expression type, LocalVariableReference var, Expression expr,
Statement stmt, Location l)
TypeExpr texpr = type.ResolveAsTypeTerminal (ec);
if (texpr == null)
return false;
-
- var_type = texpr.Type;
+
+ Type var_type = texpr.Type;
//
// We need an instance variable. Not sure this is the best
//
if (!(expr.eclass == ExprClass.Variable || expr.eclass == ExprClass.Value ||
expr.eclass == ExprClass.PropertyAccess || expr.eclass == ExprClass.IndexerAccess)){
- error1579 (expr.Type);
+ CollectionForeach.error1579 (expr.Type, loc);
return false;
}
if (expr.Type.IsArray) {
- array_type = expr.Type;
- element_type = TypeManager.GetElementType (array_type);
-
- empty = new EmptyExpression (element_type);
-
- array = new ArrayForeach (type, variable, expr, statement, loc);
+ array = new ArrayForeach (var_type, variable, expr, statement, loc);
return array.Resolve (ec);
} else {
- hm = ProbeCollectionType (ec, expr.Type);
- if (hm == null){
- error1579 (expr.Type);
- return false;
- }
-
- array_type = expr.Type;
- element_type = hm.element_type;
-
- empty = new EmptyExpression (hm.element_type);
+ collection = new CollectionForeach (
+ var_type, variable, expr, statement, loc);
+ return collection.Resolve (ec);
}
+ }
- bool ok = true;
+ protected override void DoEmit (EmitContext ec)
+ {
+ ILGenerator ig = ec.ig;
+
+ Label old_begin = ec.LoopBegin, old_end = ec.LoopEnd;
+ ec.LoopBegin = ig.DefineLabel ();
+ ec.LoopEnd = ig.DefineLabel ();
- ec.StartFlowBranching (FlowBranching.BranchingType.Loop, loc);
- ec.CurrentBranching.CreateSibling ();
+ if (collection != null)
+ collection.Emit (ec);
+ else
+ array.Emit (ec);
+
+ ec.LoopBegin = old_begin;
+ ec.LoopEnd = old_end;
+ }
- //
- //
- // FIXME: maybe we can apply the same trick we do in the
- // array handling to avoid creating empty and conv in some cases.
- //
- // Although it is not as important in this case, as the type
- // will not likely be object (what the enumerator will return).
- //
- conv = Convert.ExplicitConversion (ec, empty, var_type, loc);
- if (conv == null)
- ok = false;
+ protected class TemporaryVariable : Expression, IMemoryLocation
+ {
+ LocalInfo li;
- variable = variable.ResolveLValue (ec, empty);
- if (variable == null)
- ok = false;
+ public TemporaryVariable (Type type, Location loc)
+ {
+ this.type = type;
+ this.loc = loc;
+ eclass = ExprClass.Value;
+ }
- bool disposable = (hm != null) && hm.is_disposable;
- FlowBranchingException branching = null;
- if (disposable)
- branching = ec.StartFlowBranching (this);
+ public override Expression DoResolve (EmitContext ec)
+ {
+ if (li != null)
+ return this;
- if (!statement.Resolve (ec))
- ok = false;
+ TypeExpr te = new TypeExpression (type, loc);
+ li = ec.CurrentBlock.AddTemporaryVariable (te, loc);
+ if (!li.Resolve (ec))
+ return null;
- if (disposable) {
- ResolveFinally (branching);
- ec.EndFlowBranching ();
- } else
- emit_finally = true;
+ AnonymousContainer am = ec.CurrentAnonymousMethod;
+ if ((am != null) && am.IsIterator)
+ ec.CaptureVariable (li);
- ec.EndFlowBranching ();
+ return this;
+ }
- return ok;
- }
-
- //
- // Retrieves a `public bool MoveNext ()' method from the Type `t'
- //
- static MethodInfo FetchMethodMoveNext (Type t)
- {
- MemberList move_next_list;
-
- move_next_list = TypeContainer.FindMembers (
- t, MemberTypes.Method,
- BindingFlags.Public | BindingFlags.Instance,
- Type.FilterName, "MoveNext");
- if (move_next_list.Count == 0)
- return null;
+ public override void Emit (EmitContext ec)
+ {
+ ILGenerator ig = ec.ig;
- foreach (MemberInfo m in move_next_list){
- MethodInfo mi = (MethodInfo) m;
- Type [] args;
-
- args = TypeManager.GetArgumentTypes (mi);
- if (args != null && args.Length == 0){
- if (TypeManager.TypeToCoreType (mi.ReturnType) == TypeManager.bool_type)
- return mi;
+ if (li.FieldBuilder != null) {
+ ig.Emit (OpCodes.Ldarg_0);
+ ig.Emit (OpCodes.Ldfld, li.FieldBuilder);
+ } else {
+ ig.Emit (OpCodes.Ldloc, li.LocalBuilder);
}
}
- return null;
- }
-
- //
- // Retrieves a `public T get_Current ()' method from the Type `t'
- //
- static MethodInfo FetchMethodGetCurrent (Type t)
- {
- MemberList get_current_list;
-
- get_current_list = TypeContainer.FindMembers (
- t, MemberTypes.Method,
- BindingFlags.Public | BindingFlags.Instance,
- Type.FilterName, "get_Current");
- if (get_current_list.Count == 0)
- return null;
-
- foreach (MemberInfo m in get_current_list){
- MethodInfo mi = (MethodInfo) m;
- Type [] args;
-
- args = TypeManager.GetArgumentTypes (mi);
- if (args != null && args.Length == 0)
- return mi;
- }
- return null;
- }
-
- //
- // Retrieves a `public void Dispose ()' method from the Type `t'
- //
- static MethodInfo FetchMethodDispose (Type t)
- {
- MemberList dispose_list;
-
- dispose_list = TypeContainer.FindMembers (
- t, MemberTypes.Method,
- BindingFlags.Public | BindingFlags.Instance,
- Type.FilterName, "Dispose");
- if (dispose_list.Count == 0)
- return null;
-
- foreach (MemberInfo m in dispose_list){
- MethodInfo mi = (MethodInfo) m;
- Type [] args;
-
- args = TypeManager.GetArgumentTypes (mi);
- if (args != null && args.Length == 0){
- if (mi.ReturnType == TypeManager.void_type)
- return mi;
- }
- }
- return null;
- }
-
- //
- // This struct records the helper methods used by the Foreach construct
- //
- class ForeachHelperMethods {
- public EmitContext ec;
- public MethodInfo get_enumerator;
- public MethodInfo move_next;
- public MethodInfo get_current;
- public Type element_type;
- public Type enumerator_type;
- public bool is_disposable;
-
- public ForeachHelperMethods (EmitContext ec)
- {
- this.ec = ec;
- this.element_type = TypeManager.object_type;
- this.enumerator_type = TypeManager.ienumerator_type;
- this.is_disposable = true;
- }
- }
-
- static bool GetEnumeratorFilter (MemberInfo m, object criteria)
- {
- if (m == null)
- return false;
-
- if (!(m is MethodInfo))
- return false;
-
- if (m.Name != "GetEnumerator")
- return false;
-
- MethodInfo mi = (MethodInfo) m;
- Type [] args = TypeManager.GetArgumentTypes (mi);
- if (args != null){
- if (args.Length != 0)
- return false;
- }
- ForeachHelperMethods hm = (ForeachHelperMethods) criteria;
-
- // Check whether GetEnumerator is public
- if ((mi.Attributes & MethodAttributes.Public) != MethodAttributes.Public)
- return false;
-
- if ((mi.ReturnType == TypeManager.ienumerator_type) && (mi.DeclaringType == TypeManager.string_type))
- //
- // Apply the same optimization as MS: skip the GetEnumerator
- // returning an IEnumerator, and use the one returning a
- // CharEnumerator instead. This allows us to avoid the
- // try-finally block and the boxing.
- //
- return false;
-
- //
- // Ok, we can access it, now make sure that we can do something
- // with this `GetEnumerator'
- //
-
- Type return_type = mi.ReturnType;
- if (mi.ReturnType == TypeManager.ienumerator_type ||
- TypeManager.ienumerator_type.IsAssignableFrom (return_type) ||
- (!RootContext.StdLib && TypeManager.ImplementsInterface (return_type, TypeManager.ienumerator_type))) {
-
- //
- // If it is not an interface, lets try to find the methods ourselves.
- // For example, if we have:
- // public class Foo : IEnumerator { public bool MoveNext () {} public int Current { get {}}}
- // We can avoid the iface call. This is a runtime perf boost.
- // even bigger if we have a ValueType, because we avoid the cost
- // of boxing.
- //
- // We have to make sure that both methods exist for us to take
- // this path. If one of the methods does not exist, we will just
- // use the interface. Sadly, this complex if statement is the only
- // way I could do this without a goto
- //
-
- if (return_type.IsInterface ||
- (hm.move_next = FetchMethodMoveNext (return_type)) == null ||
- (hm.get_current = FetchMethodGetCurrent (return_type)) == null) {
-
- hm.move_next = TypeManager.bool_movenext_void;
- hm.get_current = TypeManager.object_getcurrent_void;
- return true;
- }
-
- } else {
-
- //
- // Ok, so they dont return an IEnumerable, we will have to
- // find if they support the GetEnumerator pattern.
- //
-
- hm.move_next = FetchMethodMoveNext (return_type);
- if (hm.move_next == null)
- return false;
-
- hm.get_current = FetchMethodGetCurrent (return_type);
- if (hm.get_current == null)
- return false;
- }
-
- hm.element_type = hm.get_current.ReturnType;
- hm.enumerator_type = return_type;
- hm.is_disposable = !hm.enumerator_type.IsSealed ||
- TypeManager.ImplementsInterface (
- hm.enumerator_type, TypeManager.idisposable_type);
-
- return true;
- }
-
- /// <summary>
- /// This filter is used to find the GetEnumerator method
- /// on which IEnumerator operates
- /// </summary>
- static MemberFilter FilterEnumerator;
-
- static Foreach ()
- {
- FilterEnumerator = new MemberFilter (GetEnumeratorFilter);
- }
-
- void error1579 (Type t)
- {
- Report.Error (1579, loc,
- "foreach statement cannot operate on variables of type `" +
- t.FullName + "' because that class does not provide a " +
- " GetEnumerator method or it is inaccessible");
- }
-
- static bool TryType (Type t, ForeachHelperMethods hm)
- {
- MemberList mi;
-
- mi = TypeContainer.FindMembers (t, MemberTypes.Method,
- BindingFlags.Public | BindingFlags.NonPublic |
- BindingFlags.Instance | BindingFlags.DeclaredOnly,
- FilterEnumerator, hm);
-
- if (mi.Count == 0)
- return false;
-
- hm.get_enumerator = (MethodInfo) mi [0];
- return true;
- }
-
- //
- // Looks for a usable GetEnumerator in the Type, and if found returns
- // the three methods that participate: GetEnumerator, MoveNext and get_Current
- //
- ForeachHelperMethods ProbeCollectionType (EmitContext ec, Type t)
- {
- ForeachHelperMethods hm = new ForeachHelperMethods (ec);
-
- for (Type tt = t; tt != null && tt != TypeManager.object_type;){
- if (TryType (tt, hm))
- return hm;
- tt = tt.BaseType;
- }
-
- //
- // Now try to find the method in the interfaces
- //
- while (t != null){
- Type [] ifaces = t.GetInterfaces ();
-
- foreach (Type i in ifaces){
- if (TryType (i, hm))
- return hm;
- }
-
- //
- // Since TypeBuilder.GetInterfaces only returns the interface
- // types for this type, we have to keep looping, but once
- // we hit a non-TypeBuilder (ie, a Type), then we know we are
- // done, because it returns all the types
- //
- if ((t is TypeBuilder))
- t = t.BaseType;
- else
- break;
- }
-
- return null;
- }
-
- //
- // FIXME: possible optimization.
- // We might be able to avoid creating `empty' if the type is the sam
- //
- bool EmitCollectionForeach (EmitContext ec)
- {
- ILGenerator ig = ec.ig;
-
- enumerator = new VariableStorage (ec, hm.enumerator_type);
- enumerator.EmitThis (ig);
- //
- // Instantiate the enumerator
- //
- if (expr.Type.IsValueType){
- IMemoryLocation ml = expr as IMemoryLocation;
- // Load the address of the value type.
- if (ml == null) {
- // This happens if, for example, you have a property
- // returning a struct which is IEnumerable
- LocalBuilder t = ec.GetTemporaryLocal (expr.Type);
- expr.Emit(ec);
- ig.Emit (OpCodes.Stloc, t);
- ig.Emit (OpCodes.Ldloca, t);
- ec.FreeTemporaryLocal (t, expr.Type);
- } else {
- ml.AddressOf (ec, AddressOp.Load);
- }
-
- // Emit the call.
- if (hm.get_enumerator.DeclaringType.IsValueType) {
- // the method is declared on the value type
- ig.Emit (OpCodes.Call, hm.get_enumerator);
- } else {
- // it is an interface method, so we must box
- ig.Emit (OpCodes.Box, expr.Type);
- ig.Emit (OpCodes.Callvirt, hm.get_enumerator);
- }
- } else {
- expr.Emit (ec);
- ig.Emit (OpCodes.Callvirt, hm.get_enumerator);
- }
- enumerator.EmitStore (ig);
-
- //
- // Protect the code in a try/finalize block, so that
- // if the beast implement IDisposable, we get rid of it
- //
- if (hm.is_disposable && emit_finally)
- ig.BeginExceptionBlock ();
-
- Label end_try = ig.DefineLabel ();
-
- ig.MarkLabel (ec.LoopBegin);
-
- enumerator.EmitCall (ig, hm.move_next);
-
- ig.Emit (OpCodes.Brfalse, end_try);
-
- if (ec.InIterator)
- ig.Emit (OpCodes.Ldarg_0);
-
- enumerator.EmitCall (ig, hm.get_current);
-
- if (ec.InIterator){
- conv.Emit (ec);
- ig.Emit (OpCodes.Stfld, ((LocalVariableReference) variable).local_info.FieldBuilder);
- } else
- ((IAssignMethod)variable).EmitAssign (ec, conv, false, false);
-
- statement.Emit (ec);
- ig.Emit (OpCodes.Br, ec.LoopBegin);
- ig.MarkLabel (end_try);
-
- // The runtime provides this for us.
- // ig.Emit (OpCodes.Leave, end);
-
- //
- // Now the finally block
- //
- if (hm.is_disposable) {
- DoEmitFinally (ec);
- if (emit_finally)
- ig.EndExceptionBlock ();
- }
-
- ig.MarkLabel (ec.LoopEnd);
- return false;
- }
-
- public override void EmitFinally (EmitContext ec)
- {
- ILGenerator ig = ec.ig;
-
- if (hm.enumerator_type.IsValueType) {
- enumerator.EmitThis (ig);
-
- MethodInfo mi = FetchMethodDispose (hm.enumerator_type);
- if (mi != null) {
- enumerator.EmitLoadAddress (ig);
- ig.Emit (OpCodes.Call, mi);
- } else {
- enumerator.EmitLoad (ig);
- ig.Emit (OpCodes.Box, hm.enumerator_type);
- ig.Emit (OpCodes.Callvirt, TypeManager.void_dispose_void);
- }
- } else {
- Label call_dispose = ig.DefineLabel ();
-
- enumerator.EmitThis (ig);
- enumerator.EmitLoad (ig);
- ig.Emit (OpCodes.Isinst, TypeManager.idisposable_type);
- ig.Emit (OpCodes.Dup);
- ig.Emit (OpCodes.Brtrue_S, call_dispose);
- ig.Emit (OpCodes.Pop);
-
- Label end_finally = ig.DefineLabel ();
- ig.Emit (OpCodes.Br, end_finally);
- ig.MarkLabel (call_dispose);
- ig.Emit (OpCodes.Callvirt, TypeManager.void_dispose_void);
- ig.MarkLabel (end_finally);
-
- if (emit_finally)
- ig.Emit (OpCodes.Endfinally);
- }
- }
-
- protected override void DoEmit (EmitContext ec)
- {
- ILGenerator ig = ec.ig;
-
- Label old_begin = ec.LoopBegin, old_end = ec.LoopEnd;
- ec.LoopBegin = ig.DefineLabel ();
- ec.LoopEnd = ig.DefineLabel ();
-
- if (hm != null)
- EmitCollectionForeach (ec);
- else
- array.Emit (ec);
-
- ec.LoopBegin = old_begin;
- ec.LoopEnd = old_end;
- }
-
- protected class TemporaryVariable : Expression
- {
- FieldBuilder fb;
- LocalBuilder local;
-
- public TemporaryVariable (Type type, Location loc)
- {
- this.type = type;
- this.loc = loc;
- eclass = ExprClass.Value;
- }
-
- static int count;
-
- public override Expression DoResolve (EmitContext ec)
- {
- if (ec.InIterator) {
- count++;
- fb = ec.CurrentIterator.MapVariable (
- "s_", count.ToString (), type);
- } else
- local = ec.ig.DeclareLocal (type);
-
- return this;
- }
-
- public override void Emit (EmitContext ec)
+ public void EmitLoadAddress (EmitContext ec)
{
ILGenerator ig = ec.ig;
- if (fb != null) {
+ if (li.FieldBuilder != null) {
ig.Emit (OpCodes.Ldarg_0);
- ig.Emit (OpCodes.Ldfld, fb);
+ ig.Emit (OpCodes.Ldflda, li.FieldBuilder);
} else {
- ig.Emit (OpCodes.Ldloc, local);
+ ig.Emit (OpCodes.Ldloca, li.LocalBuilder);
}
}
public void Store (EmitContext ec, Expression right_side)
{
- if (fb != null)
+ if (li.FieldBuilder != null)
ec.ig.Emit (OpCodes.Ldarg_0);
+
right_side.Emit (ec);
- if (fb == null)
- ec.ig.Emit (OpCodes.Stloc, local);
- else
- ec.ig.Emit (OpCodes.Stfld, fb);
+ if (li.FieldBuilder != null) {
+ ec.ig.Emit (OpCodes.Stfld, li.FieldBuilder);
+ } else {
+ ec.ig.Emit (OpCodes.Stloc, li.LocalBuilder);
+ }
}
- public void EmitThis (ILGenerator ig)
+ public void EmitThis (EmitContext ec)
{
- if (fb != null)
- ig.Emit (OpCodes.Ldarg_0);
+ if (li.FieldBuilder != null) {
+ ec.ig.Emit (OpCodes.Ldarg_0);
+ }
}
public void EmitStore (ILGenerator ig)
{
- if (fb == null)
- ig.Emit (OpCodes.Stloc, local);
+ if (li.FieldBuilder != null)
+ ig.Emit (OpCodes.Stfld, li.FieldBuilder);
else
- ig.Emit (OpCodes.Stfld, fb);
+ ig.Emit (OpCodes.Stloc, li.LocalBuilder);
+ }
+
+ public void AddressOf (EmitContext ec, AddressOp mode)
+ {
+ EmitLoadAddress (ec);
}
}
public void Initialize (EmitContext ec)
{
- EmitThis (ec.ig);
+ EmitThis (ec);
ec.ig.Emit (OpCodes.Ldc_I4_0);
EmitStore (ec.ig);
}
public void Increment (EmitContext ec)
{
- EmitThis (ec.ig);
+ EmitThis (ec);
Emit (ec);
ec.ig.Emit (OpCodes.Ldc_I4_1);
ec.ig.Emit (OpCodes.Add);
protected class ArrayForeach : Statement
{
- Expression type, variable, expr, conv;
+ Expression variable, expr, conv;
Statement statement;
- Type array_type, element_type;
+ Type array_type;
Type var_type;
TemporaryVariable[] lengths;
ArrayCounter[] counter;
TemporaryVariable copy;
Expression access;
- public ArrayForeach (Expression type, Expression var,
+ public ArrayForeach (Type var_type, Expression var,
Expression expr, Statement stmt, Location l)
{
- this.type = type;
+ this.var_type = var_type;
this.variable = var;
this.expr = expr;
statement = stmt;
}
public override bool Resolve (EmitContext ec)
- {
- TypeExpr texpr = type.ResolveAsTypeTerminal (ec);
- if (texpr == null)
- return false;
-
- var_type = texpr.Type;
-
+ {
array_type = expr.Type;
- element_type = TypeManager.GetElementType (array_type);
rank = array_type.GetArrayRank ();
copy = new TemporaryVariable (array_type, loc);
test [i] = ig.DefineLabel ();
loop [i] = ig.DefineLabel ();
- lengths [i].EmitThis (ig);
+ lengths [i].EmitThis (ec);
((ArrayAccess) access).EmitGetLength (ec, i);
lengths [i].EmitStore (ig);
}
ig.MarkLabel (ec.LoopEnd);
}
}
+
+ protected class CollectionForeach : ExceptionStatement
+ {
+ Expression variable, expr;
+ Statement statement;
+
+ TemporaryVariable enumerator;
+ Expression init;
+ Statement loop;
+
+ MethodGroupExpr get_enumerator;
+ PropertyExpr get_current;
+ MethodInfo move_next;
+ Type var_type, enumerator_type;
+ bool is_disposable;
+
+ public CollectionForeach (Type var_type, Expression var,
+ Expression expr, Statement stmt, Location l)
+ {
+ this.var_type = var_type;
+ this.variable = var;
+ this.expr = expr;
+ statement = stmt;
+ loc = l;
+ }
+
+ bool GetEnumeratorFilter (EmitContext ec, MethodInfo mi)
+ {
+ Type [] args = TypeManager.GetArgumentTypes (mi);
+ if (args != null){
+ if (args.Length != 0)
+ return false;
+ }
+
+ if (TypeManager.IsOverride (mi))
+ return false;
+
+ // Check whether GetEnumerator is public
+ if ((mi.Attributes & MethodAttributes.Public) != MethodAttributes.Public)
+ return false;
+
+ if ((mi.ReturnType == TypeManager.ienumerator_type) && (mi.DeclaringType == TypeManager.string_type))
+ //
+ // Apply the same optimization as MS: skip the GetEnumerator
+ // returning an IEnumerator, and use the one returning a
+ // CharEnumerator instead. This allows us to avoid the
+ // try-finally block and the boxing.
+ //
+ return false;
+
+ //
+ // Ok, we can access it, now make sure that we can do something
+ // with this `GetEnumerator'
+ //
+
+ Type return_type = mi.ReturnType;
+ if (mi.ReturnType == TypeManager.ienumerator_type ||
+ TypeManager.ienumerator_type.IsAssignableFrom (return_type) ||
+ (!RootContext.StdLib && TypeManager.ImplementsInterface (return_type, TypeManager.ienumerator_type))) {
+ //
+ // If it is not an interface, lets try to find the methods ourselves.
+ // For example, if we have:
+ // public class Foo : IEnumerator { public bool MoveNext () {} public int Current { get {}}}
+ // We can avoid the iface call. This is a runtime perf boost.
+ // even bigger if we have a ValueType, because we avoid the cost
+ // of boxing.
+ //
+ // We have to make sure that both methods exist for us to take
+ // this path. If one of the methods does not exist, we will just
+ // use the interface. Sadly, this complex if statement is the only
+ // way I could do this without a goto
+ //
+
+ if (return_type.IsInterface ||
+ !FetchMoveNext (ec, return_type) ||
+ !FetchGetCurrent (ec, return_type)) {
+ move_next = TypeManager.bool_movenext_void;
+ get_current = new PropertyExpr (
+ ec, TypeManager.ienumerator_getcurrent, loc);
+ return true;
+ }
+ } else {
+ //
+ // Ok, so they dont return an IEnumerable, we will have to
+ // find if they support the GetEnumerator pattern.
+ //
+
+ if (!FetchMoveNext (ec, return_type))
+ return false;
+
+ if (!FetchGetCurrent (ec, return_type))
+ return false;
+ }
+
+ enumerator_type = return_type;
+ is_disposable = !enumerator_type.IsSealed ||
+ TypeManager.ImplementsInterface (
+ enumerator_type, TypeManager.idisposable_type);
+
+ return true;
+ }
+
+ //
+ // Retrieves a `public bool MoveNext ()' method from the Type `t'
+ //
+ bool FetchMoveNext (EmitContext ec, Type t)
+ {
+ MemberList move_next_list;
+
+ move_next_list = TypeContainer.FindMembers (
+ t, MemberTypes.Method,
+ BindingFlags.Public | BindingFlags.Instance,
+ Type.FilterName, "MoveNext");
+ if (move_next_list.Count == 0)
+ return false;
+
+ foreach (MemberInfo m in move_next_list){
+ MethodInfo mi = (MethodInfo) m;
+ Type [] args;
+
+ args = TypeManager.GetArgumentTypes (mi);
+ if ((args != null) && (args.Length == 0) &&
+ TypeManager.TypeToCoreType (mi.ReturnType) == TypeManager.bool_type) {
+ move_next = mi;
+ return true;
+ }
+ }
+
+ return false;
+ }
+
+ //
+ // Retrieves a `public T get_Current ()' method from the Type `t'
+ //
+ bool FetchGetCurrent (EmitContext ec, Type t)
+ {
+ PropertyExpr pe = Expression.MemberLookup (
+ ec, t, "Current", MemberTypes.Property,
+ Expression.AllBindingFlags, loc) as PropertyExpr;
+ if (pe == null)
+ return false;
+
+ get_current = pe;
+ return true;
+ }
+
+ //
+ // Retrieves a `public void Dispose ()' method from the Type `t'
+ //
+ static MethodInfo FetchMethodDispose (Type t)
+ {
+ MemberList dispose_list;
+
+ dispose_list = TypeContainer.FindMembers (
+ t, MemberTypes.Method,
+ BindingFlags.Public | BindingFlags.Instance,
+ Type.FilterName, "Dispose");
+ if (dispose_list.Count == 0)
+ return null;
+
+ foreach (MemberInfo m in dispose_list){
+ MethodInfo mi = (MethodInfo) m;
+ Type [] args;
+
+ args = TypeManager.GetArgumentTypes (mi);
+ if (args != null && args.Length == 0){
+ if (mi.ReturnType == TypeManager.void_type)
+ return mi;
+ }
+ }
+ return null;
+ }
+
+ static public void error1579 (Type t, Location loc)
+ {
+ Report.Error (1579, loc, "foreach statement cannot operate on " +
+ "variables of type `{0}' because that class does " +
+ "not provide a GetEnumerator method or it is " +
+ "inaccessible", t.FullName);
+ }
+
+ bool TryType (EmitContext ec, Type t)
+ {
+ MethodGroupExpr mg = Expression.MemberLookup (
+ ec, t, "GetEnumerator", MemberTypes.Method,
+ Expression.AllBindingFlags, loc) as MethodGroupExpr;
+ if (mg == null)
+ return false;
+
+ foreach (MethodBase mb in mg.Methods) {
+ if (!GetEnumeratorFilter (ec, (MethodInfo) mb))
+ continue;
+
+ MethodInfo[] mi = new MethodInfo[] { (MethodInfo) mb };
+ get_enumerator = new MethodGroupExpr (mi, loc);
+
+ if (t != expr.Type) {
+ expr = Convert.ExplicitConversion (
+ ec, expr, t, loc);
+ if (expr == null)
+ throw new InternalErrorException ();
+ }
+
+ get_enumerator.InstanceExpression = expr;
+ get_enumerator.IsBase = t != expr.Type;
+
+ return true;
+ }
+
+ return false;
+ }
+
+ bool ProbeCollectionType (EmitContext ec, Type t)
+ {
+ for (Type tt = t; tt != null && tt != TypeManager.object_type;){
+ if (TryType (ec, tt))
+ return true;
+ tt = tt.BaseType;
+ }
+
+ //
+ // Now try to find the method in the interfaces
+ //
+ while (t != null){
+ Type [] ifaces = t.GetInterfaces ();
+
+ foreach (Type i in ifaces){
+ if (TryType (ec, i))
+ return true;
+ }
+
+ //
+ // Since TypeBuilder.GetInterfaces only returns the interface
+ // types for this type, we have to keep looping, but once
+ // we hit a non-TypeBuilder (ie, a Type), then we know we are
+ // done, because it returns all the types
+ //
+ if ((t is TypeBuilder))
+ t = t.BaseType;
+ else
+ break;
+ }
+
+ return false;
+ }
+
+ public override bool Resolve (EmitContext ec)
+ {
+ enumerator_type = TypeManager.ienumerator_type;
+ is_disposable = true;
+
+ if (!ProbeCollectionType (ec, expr.Type)) {
+ error1579 (expr.Type, loc);
+ return false;
+ }
+
+ enumerator = new TemporaryVariable (enumerator_type, loc);
+ enumerator.Resolve (ec);
+
+ init = new Invocation (get_enumerator, new ArrayList (), loc);
+ init = init.Resolve (ec);
+ if (init == null)
+ return false;
+
+ Expression move_next_expr;
+ {
+ MemberInfo[] mi = new MemberInfo[] { move_next };
+ MethodGroupExpr mg = new MethodGroupExpr (mi, loc);
+ mg.InstanceExpression = enumerator;
+
+ move_next_expr = new Invocation (mg, new ArrayList (), loc);
+ }
+
+ get_current.InstanceExpression = enumerator;
+
+ Statement block = new CollectionForeachStatement (
+ var_type, variable, get_current, statement, loc);
+
+ loop = new While (move_next_expr, block, loc);
+
+ bool ok = true;
+
+ ec.StartFlowBranching (FlowBranching.BranchingType.Loop, loc);
+ ec.CurrentBranching.CreateSibling ();
+
+ FlowBranchingException branching = null;
+ if (is_disposable)
+ branching = ec.StartFlowBranching (this);
+
+ if (!loop.Resolve (ec))
+ ok = false;
+
+ if (is_disposable) {
+ ResolveFinally (branching);
+ ec.EndFlowBranching ();
+ } else
+ emit_finally = true;
+
+ ec.EndFlowBranching ();
+
+ return ok;
+ }
+
+ protected override void DoEmit (EmitContext ec)
+ {
+ ILGenerator ig = ec.ig;
+
+ enumerator.Store (ec, init);
+
+ //
+ // Protect the code in a try/finalize block, so that
+ // if the beast implement IDisposable, we get rid of it
+ //
+ if (is_disposable && emit_finally)
+ ig.BeginExceptionBlock ();
+
+ loop.Emit (ec);
+
+ //
+ // Now the finally block
+ //
+ if (is_disposable) {
+ DoEmitFinally (ec);
+ if (emit_finally)
+ ig.EndExceptionBlock ();
+ }
+ }
+
+
+ public override void EmitFinally (EmitContext ec)
+ {
+ ILGenerator ig = ec.ig;
+
+ if (enumerator_type.IsValueType) {
+ enumerator.Emit (ec);
+
+ MethodInfo mi = FetchMethodDispose (enumerator_type);
+ if (mi != null) {
+ enumerator.EmitLoadAddress (ec);
+ ig.Emit (OpCodes.Call, mi);
+ } else {
+ enumerator.Emit (ec);
+ ig.Emit (OpCodes.Box, enumerator_type);
+ ig.Emit (OpCodes.Callvirt, TypeManager.void_dispose_void);
+ }
+ } else {
+ Label call_dispose = ig.DefineLabel ();
+
+ enumerator.Emit (ec);
+ ig.Emit (OpCodes.Isinst, TypeManager.idisposable_type);
+ ig.Emit (OpCodes.Dup);
+ ig.Emit (OpCodes.Brtrue_S, call_dispose);
+ ig.Emit (OpCodes.Pop);
+
+ Label end_finally = ig.DefineLabel ();
+ ig.Emit (OpCodes.Br, end_finally);
+
+ ig.MarkLabel (call_dispose);
+ ig.Emit (OpCodes.Callvirt, TypeManager.void_dispose_void);
+ ig.MarkLabel (end_finally);
+ }
+ }
+ }
+
+ protected class CollectionForeachStatement : Statement
+ {
+ Type type;
+ Expression variable, current, conv;
+ Statement statement;
+ Assign assign;
+
+ public CollectionForeachStatement (Type type, Expression variable,
+ Expression current, Statement statement,
+ Location loc)
+ {
+ this.type = type;
+ this.variable = variable;
+ this.current = current;
+ this.statement = statement;
+ this.loc = loc;
+ }
+
+ public override bool Resolve (EmitContext ec)
+ {
+ current = current.Resolve (ec);
+ if (current == null)
+ return false;
+
+ conv = Convert.ExplicitConversion (ec, current, type, loc);
+ if (conv == null)
+ return false;
+
+ assign = new Assign (variable, conv, loc);
+ if (assign.Resolve (ec) == null)
+ return false;
+
+ if (!statement.Resolve (ec))
+ return false;
+
+ return true;
+ }
+
+ protected override void DoEmit (EmitContext ec)
+ {
+ assign.EmitStatement (ec);
+ statement.Emit (ec);
+ }
+ }
}
}
projects / mono.git / blobdiff