1269 lines
34 KiB
C#
1269 lines
34 KiB
C#
//
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// iterators.cs: Support for implementing iterators
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//
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// Author:
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// Miguel de Icaza (miguel@ximian.com)
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// Marek Safar (marek.safar@gmail.com)
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//
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// Dual licensed under the terms of the MIT X11 or GNU GPL
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// Copyright 2003 Ximian, Inc.
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// Copyright 2003-2008 Novell, Inc.
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// Copyright 2011 Xamarin Inc.
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//
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using System;
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using System.Collections.Generic;
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using Mono.CompilerServices.SymbolWriter;
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#if STATIC
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using IKVM.Reflection.Emit;
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#else
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using System.Reflection.Emit;
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#endif
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namespace Mono.CSharp
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{
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public abstract class YieldStatement<T> : ResumableStatement where T : StateMachineInitializer
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{
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protected Expression expr;
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protected bool unwind_protect;
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protected T machine_initializer;
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int resume_pc;
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ExceptionStatement inside_try_block;
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TryCatch inside_catch_block;
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protected YieldStatement (Expression expr, Location l)
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{
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this.expr = expr;
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loc = l;
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}
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public Expression Expr {
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get { return this.expr; }
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}
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protected override void CloneTo (CloneContext clonectx, Statement t)
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{
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var target = (YieldStatement<T>) t;
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target.expr = expr.Clone (clonectx);
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}
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protected override void DoEmit (EmitContext ec)
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{
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machine_initializer.InjectYield (ec, expr, resume_pc, unwind_protect, resume_point);
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}
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protected override bool DoFlowAnalysis (FlowAnalysisContext fc)
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{
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expr.FlowAnalysis (fc);
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RegisterResumePoint ();
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return false;
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}
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public override bool Resolve (BlockContext bc)
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{
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expr = expr.Resolve (bc);
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if (expr == null)
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return false;
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machine_initializer = bc.CurrentAnonymousMethod as T;
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inside_try_block = bc.CurrentTryBlock;
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inside_catch_block = bc.CurrentTryCatch;
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return true;
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}
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public void RegisterResumePoint ()
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{
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if (resume_pc != 0)
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return;
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if (inside_try_block == null) {
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resume_pc = machine_initializer.AddResumePoint (this);
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} else {
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resume_pc = inside_try_block.AddResumePoint (this, resume_pc, machine_initializer, inside_catch_block);
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unwind_protect = true;
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inside_try_block = null;
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}
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}
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}
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public class Yield : YieldStatement<Iterator>
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{
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public Yield (Expression expr, Location loc)
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: base (expr, loc)
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{
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}
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public static bool CheckContext (BlockContext bc, Location loc)
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{
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if (!bc.CurrentAnonymousMethod.IsIterator) {
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bc.Report.Error (1621, loc,
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"The yield statement cannot be used inside anonymous method blocks");
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return false;
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}
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if (bc.HasSet (ResolveContext.Options.FinallyScope)) {
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bc.Report.Error (1625, loc, "Cannot yield in the body of a finally clause");
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return false;
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}
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return true;
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}
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public override bool Resolve (BlockContext bc)
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{
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if (!CheckContext (bc, loc))
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return false;
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if (bc.HasAny (ResolveContext.Options.TryWithCatchScope)) {
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bc.Report.Error (1626, loc, "Cannot yield a value in the body of a try block with a catch clause");
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}
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if (bc.HasSet (ResolveContext.Options.CatchScope)) {
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bc.Report.Error (1631, loc, "Cannot yield a value in the body of a catch clause");
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}
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if (!base.Resolve (bc))
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return false;
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var otype = bc.CurrentIterator.OriginalIteratorType;
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if (expr.Type != otype) {
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expr = Convert.ImplicitConversionRequired (bc, expr, otype, loc);
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if (expr == null)
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return false;
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}
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return true;
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}
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public override object Accept (StructuralVisitor visitor)
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{
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return visitor.Visit (this);
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}
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}
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public class YieldBreak : ExitStatement
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{
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Iterator iterator;
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public YieldBreak (Location l)
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{
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loc = l;
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}
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protected override bool IsLocalExit {
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get {
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return false;
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}
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}
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protected override void CloneTo (CloneContext clonectx, Statement target)
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{
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}
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protected override bool DoResolve (BlockContext bc)
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{
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iterator = bc.CurrentIterator;
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return Yield.CheckContext (bc, loc);
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}
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protected override void DoEmit (EmitContext ec)
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{
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iterator.EmitYieldBreak (ec, unwind_protect);
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}
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protected override bool DoFlowAnalysis (FlowAnalysisContext fc)
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{
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return true;
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}
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public override Reachability MarkReachable (Reachability rc)
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{
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base.MarkReachable (rc);
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return Reachability.CreateUnreachable ();
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}
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public override object Accept (StructuralVisitor visitor)
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{
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return visitor.Visit (this);
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}
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}
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public abstract class StateMachine : AnonymousMethodStorey
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{
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public enum State
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{
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Running = -3, // Used only in CurrentPC, never stored into $PC
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Uninitialized = -2,
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After = -1,
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Start = 0
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}
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Field pc_field;
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StateMachineMethod method;
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protected StateMachine (ParametersBlock block, TypeDefinition parent, MemberBase host, TypeParameters tparams, string name, MemberKind kind)
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: base (block, parent, host, tparams, name, kind)
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{
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OriginalTypeParameters = tparams;
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}
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#region Properties
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public TypeParameters OriginalTypeParameters { get; private set; }
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public StateMachineMethod StateMachineMethod {
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get {
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return method;
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}
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}
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public Field PC {
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get {
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return pc_field;
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}
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}
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#endregion
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public void AddEntryMethod (StateMachineMethod method)
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{
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if (this.method != null)
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throw new InternalErrorException ();
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this.method = method;
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Members.Add (method);
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}
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protected override bool DoDefineMembers ()
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{
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pc_field = AddCompilerGeneratedField ("$PC", new TypeExpression (Compiler.BuiltinTypes.Int, Location));
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return base.DoDefineMembers ();
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}
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protected override string GetVariableMangledName (ResolveContext rc, LocalVariable local_info)
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{
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if (local_info.IsCompilerGenerated)
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return base.GetVariableMangledName (rc, local_info);
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//
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// Special format which encodes original variable name and
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// it's scope to support lifted variables debugging. This
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// is same what csc does and allows to correctly set fields
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// scope information (like ambiguity, out of scope, etc).
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//
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var id = rc.CurrentBlock.Explicit.GetDebugSymbolScopeIndex ();
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return "<" + local_info.Name + ">__" + id;
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}
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}
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class IteratorStorey : StateMachine
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{
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class GetEnumeratorMethod : StateMachineMethod
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{
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sealed class GetEnumeratorStatement : Statement
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{
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readonly IteratorStorey host;
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readonly StateMachineMethod host_method;
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Expression new_storey;
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public GetEnumeratorStatement (IteratorStorey host, StateMachineMethod host_method)
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{
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this.host = host;
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this.host_method = host_method;
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loc = host_method.Location;
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}
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protected override void CloneTo (CloneContext clonectx, Statement target)
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{
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throw new NotSupportedException ();
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}
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public override bool Resolve (BlockContext ec)
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{
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TypeExpression storey_type_expr = new TypeExpression (host.Definition, loc);
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List<Expression> init = null;
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if (host.hoisted_this != null) {
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init = new List<Expression> (host.hoisted_params == null ? 1 : host.HoistedParameters.Count + 1);
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HoistedThis ht = host.hoisted_this;
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FieldExpr from = new FieldExpr (ht.Field, loc);
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from.InstanceExpression = new CompilerGeneratedThis (ec.CurrentType, loc);
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init.Add (new ElementInitializer (ht.Field.Name, from, loc));
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}
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if (host.hoisted_params != null) {
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if (init == null)
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init = new List<Expression> (host.HoistedParameters.Count);
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for (int i = 0; i < host.hoisted_params.Count; ++i) {
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HoistedParameter hp = host.hoisted_params [i];
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HoistedParameter hp_cp = host.hoisted_params_copy [i] ?? hp;
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FieldExpr from = new FieldExpr (hp_cp.Field, loc);
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from.InstanceExpression = new CompilerGeneratedThis (ec.CurrentType, loc);
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init.Add (new ElementInitializer (hp.Field.Name, from, loc));
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}
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}
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if (init != null) {
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new_storey = new NewInitialize (storey_type_expr, null,
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new CollectionOrObjectInitializers (init, loc), loc);
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} else {
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new_storey = new New (storey_type_expr, null, loc);
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}
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new_storey = new_storey.Resolve (ec);
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if (new_storey != null)
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new_storey = Convert.ImplicitConversionRequired (ec, new_storey, host_method.MemberType, loc);
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return true;
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}
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protected override void DoEmit (EmitContext ec)
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{
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Label label_init = ec.DefineLabel ();
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ec.EmitThis ();
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ec.Emit (OpCodes.Ldflda, host.PC.Spec);
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ec.EmitInt ((int) State.Start);
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ec.EmitInt ((int) State.Uninitialized);
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var m = ec.Module.PredefinedMembers.InterlockedCompareExchange.Resolve (loc);
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if (m != null)
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ec.Emit (OpCodes.Call, m);
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ec.EmitInt ((int) State.Uninitialized);
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ec.Emit (OpCodes.Bne_Un_S, label_init);
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ec.EmitThis ();
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ec.Emit (OpCodes.Ret);
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ec.MarkLabel (label_init);
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new_storey.Emit (ec);
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ec.Emit (OpCodes.Ret);
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}
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protected override bool DoFlowAnalysis (FlowAnalysisContext fc)
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{
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throw new NotImplementedException ();
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}
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public override Reachability MarkReachable (Reachability rc)
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{
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base.MarkReachable (rc);
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return Reachability.CreateUnreachable ();
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}
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}
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GetEnumeratorMethod (IteratorStorey host, FullNamedExpression returnType, MemberName name)
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: base (host, null, returnType, Modifiers.DEBUGGER_HIDDEN, name, ToplevelBlock.Flags.CompilerGenerated | ToplevelBlock.Flags.NoFlowAnalysis)
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{
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}
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public static GetEnumeratorMethod Create (IteratorStorey host, FullNamedExpression returnType, MemberName name)
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{
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return Create (host, returnType, name, null);
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}
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public static GetEnumeratorMethod Create (IteratorStorey host, FullNamedExpression returnType, MemberName name, Statement statement)
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{
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var m = new GetEnumeratorMethod (host, returnType, name);
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var stmt = statement ?? new GetEnumeratorStatement (host, m);
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m.block.AddStatement (stmt);
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return m;
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}
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}
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class DisposeMethod : StateMachineMethod
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{
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sealed class DisposeMethodStatement : Statement
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{
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Iterator iterator;
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public DisposeMethodStatement (Iterator iterator)
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{
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this.iterator = iterator;
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this.loc = iterator.Location;
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}
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protected override void CloneTo (CloneContext clonectx, Statement target)
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{
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throw new NotSupportedException ();
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}
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public override bool Resolve (BlockContext ec)
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{
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return true;
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}
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protected override void DoEmit (EmitContext ec)
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{
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ec.CurrentAnonymousMethod = iterator;
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iterator.EmitDispose (ec);
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}
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protected override bool DoFlowAnalysis (FlowAnalysisContext fc)
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{
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throw new NotImplementedException ();
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}
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}
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public DisposeMethod (IteratorStorey host)
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: base (host, null, new TypeExpression (host.Compiler.BuiltinTypes.Void, host.Location), Modifiers.PUBLIC | Modifiers.DEBUGGER_HIDDEN,
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new MemberName ("Dispose", host.Location), ToplevelBlock.Flags.CompilerGenerated | ToplevelBlock.Flags.NoFlowAnalysis)
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{
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host.Members.Add (this);
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Block.AddStatement (new DisposeMethodStatement (host.Iterator));
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}
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}
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//
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// Uses Method as method info
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//
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class DynamicMethodGroupExpr : MethodGroupExpr
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{
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readonly Method method;
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public DynamicMethodGroupExpr (Method method, Location loc)
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: base ((IList<MemberSpec>) null, null, loc)
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{
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this.method = method;
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eclass = ExprClass.Unresolved;
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}
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protected override Expression DoResolve (ResolveContext ec)
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{
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Methods = new List<MemberSpec> (1) { method.Spec };
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type = method.Parent.Definition;
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InstanceExpression = new CompilerGeneratedThis (type, Location);
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return base.DoResolve (ec);
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}
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}
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class DynamicFieldExpr : FieldExpr
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{
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readonly Field field;
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public DynamicFieldExpr (Field field, Location loc)
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: base (loc)
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{
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this.field = field;
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}
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protected override Expression DoResolve (ResolveContext ec)
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{
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spec = field.Spec;
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type = spec.MemberType;
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InstanceExpression = new CompilerGeneratedThis (type, Location);
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return base.DoResolve (ec);
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}
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}
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public readonly Iterator Iterator;
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List<HoistedParameter> hoisted_params_copy;
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TypeExpr iterator_type_expr;
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Field current_field;
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Field disposing_field;
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TypeSpec generic_enumerator_type;
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TypeSpec generic_enumerable_type;
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public IteratorStorey (Iterator iterator)
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: base (iterator.Container.ParametersBlock, iterator.Host,
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iterator.OriginalMethod as MemberBase, iterator.OriginalMethod.CurrentTypeParameters, "Iterator", MemberKind.Class)
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{
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this.Iterator = iterator;
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}
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public Field CurrentField {
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get {
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return current_field;
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}
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}
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public Field DisposingField {
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get {
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return disposing_field;
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}
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}
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public IList<HoistedParameter> HoistedParameters {
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get { return hoisted_params; }
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}
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protected override Constructor DefineDefaultConstructor (bool is_static)
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{
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var ctor = base.DefineDefaultConstructor (is_static);
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ctor.ModFlags |= Modifiers.DEBUGGER_HIDDEN;
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return ctor;
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}
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protected override TypeSpec[] ResolveBaseTypes (out FullNamedExpression base_class)
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{
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var mtype = Iterator.OriginalIteratorType;
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if (Mutator != null)
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mtype = Mutator.Mutate (mtype);
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iterator_type_expr = new TypeExpression (mtype, Location);
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var ifaces = new List<TypeSpec> (5);
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if (Iterator.IsEnumerable) {
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ifaces.Add (Compiler.BuiltinTypes.IEnumerable);
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if (Module.PredefinedTypes.IEnumerableGeneric.Define ()) {
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generic_enumerable_type = Module.PredefinedTypes.IEnumerableGeneric.TypeSpec.MakeGenericType (Module, new[] { mtype });
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ifaces.Add (generic_enumerable_type);
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}
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}
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ifaces.Add (Compiler.BuiltinTypes.IEnumerator);
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ifaces.Add (Compiler.BuiltinTypes.IDisposable);
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var ienumerator_generic = Module.PredefinedTypes.IEnumeratorGeneric;
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if (ienumerator_generic.Define ()) {
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generic_enumerator_type = ienumerator_generic.TypeSpec.MakeGenericType (Module, new [] { mtype });
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ifaces.Add (generic_enumerator_type);
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}
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base_class = null;
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base_type = Compiler.BuiltinTypes.Object;
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return ifaces.ToArray ();
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}
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protected override bool DoDefineMembers ()
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{
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current_field = AddCompilerGeneratedField ("$current", iterator_type_expr);
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disposing_field = AddCompilerGeneratedField ("$disposing", new TypeExpression (Compiler.BuiltinTypes.Bool, Location));
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if (Iterator.IsEnumerable && hoisted_params != null) {
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//
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// Iterators are independent, each GetEnumerator call has to
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// create same enumerator therefore we have to keep original values
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// around for re-initialization
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//
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hoisted_params_copy = new List<HoistedParameter> (hoisted_params.Count);
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foreach (HoistedParameter hp in hoisted_params) {
|
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//
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// Don't create field copy for unmodified captured parameters
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//
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HoistedParameter hp_copy;
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if (hp.IsAssigned) {
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hp_copy = new HoistedParameter (hp, "<$>" + hp.Field.Name);
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} else {
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hp_copy = null;
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}
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hoisted_params_copy.Add (hp_copy);
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}
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}
|
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if (generic_enumerator_type != null)
|
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Define_Current (true);
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Define_Current (false);
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new DisposeMethod (this);
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Define_Reset ();
|
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|
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if (Iterator.IsEnumerable) {
|
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FullNamedExpression explicit_iface = new TypeExpression (Compiler.BuiltinTypes.IEnumerable, Location);
|
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var name = new MemberName ("GetEnumerator", null, explicit_iface, Location.Null);
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if (generic_enumerator_type != null) {
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explicit_iface = new TypeExpression (generic_enumerable_type, Location);
|
|
var gname = new MemberName ("GetEnumerator", null, explicit_iface, Location.Null);
|
|
Method gget_enumerator = GetEnumeratorMethod.Create (this, new TypeExpression (generic_enumerator_type, Location), gname);
|
|
|
|
//
|
|
// Just call generic GetEnumerator implementation
|
|
//
|
|
var stmt = new Return (new Invocation (new DynamicMethodGroupExpr (gget_enumerator, Location), null), Location);
|
|
Method get_enumerator = GetEnumeratorMethod.Create (this, new TypeExpression (Compiler.BuiltinTypes.IEnumerator, Location), name, stmt);
|
|
|
|
Members.Add (get_enumerator);
|
|
Members.Add (gget_enumerator);
|
|
} else {
|
|
Members.Add (GetEnumeratorMethod.Create (this, new TypeExpression (Compiler.BuiltinTypes.IEnumerator, Location), name));
|
|
}
|
|
}
|
|
|
|
return base.DoDefineMembers ();
|
|
}
|
|
|
|
void Define_Current (bool is_generic)
|
|
{
|
|
TypeExpr type;
|
|
FullNamedExpression explicit_iface;
|
|
|
|
if (is_generic) {
|
|
explicit_iface = new TypeExpression (generic_enumerator_type, Location);
|
|
type = iterator_type_expr;
|
|
} else {
|
|
explicit_iface = new TypeExpression (Module.Compiler.BuiltinTypes.IEnumerator, Location);
|
|
type = new TypeExpression (Compiler.BuiltinTypes.Object, Location);
|
|
}
|
|
|
|
var name = new MemberName ("Current", null, explicit_iface, Location);
|
|
|
|
ToplevelBlock get_block = new ToplevelBlock (Compiler, ParametersCompiled.EmptyReadOnlyParameters, Location,
|
|
Block.Flags.CompilerGenerated | Block.Flags.NoFlowAnalysis);
|
|
get_block.AddStatement (new Return (new DynamicFieldExpr (CurrentField, Location), Location));
|
|
|
|
Property current = new Property (this, type, Modifiers.DEBUGGER_HIDDEN | Modifiers.COMPILER_GENERATED, name, null);
|
|
current.Get = new Property.GetMethod (current, Modifiers.COMPILER_GENERATED, null, Location);
|
|
current.Get.Block = get_block;
|
|
|
|
Members.Add (current);
|
|
}
|
|
|
|
void Define_Reset ()
|
|
{
|
|
Method reset = new Method (
|
|
this, new TypeExpression (Compiler.BuiltinTypes.Void, Location),
|
|
Modifiers.PUBLIC | Modifiers.DEBUGGER_HIDDEN | Modifiers.COMPILER_GENERATED,
|
|
new MemberName ("Reset", Location),
|
|
ParametersCompiled.EmptyReadOnlyParameters, null);
|
|
Members.Add (reset);
|
|
|
|
reset.Block = new ToplevelBlock (Compiler, reset.ParameterInfo, Location,
|
|
Block.Flags.CompilerGenerated | Block.Flags.NoFlowAnalysis);
|
|
|
|
TypeSpec ex_type = Module.PredefinedTypes.NotSupportedException.Resolve ();
|
|
if (ex_type == null)
|
|
return;
|
|
|
|
reset.Block.AddStatement (new Throw (new New (new TypeExpression (ex_type, Location), null, Location), Location));
|
|
}
|
|
|
|
protected override void EmitHoistedParameters (EmitContext ec, List<HoistedParameter> hoisted)
|
|
{
|
|
base.EmitHoistedParameters (ec, hoisted);
|
|
if (hoisted_params_copy != null)
|
|
base.EmitHoistedParameters (ec, hoisted_params_copy);
|
|
}
|
|
}
|
|
|
|
public class StateMachineMethod : Method
|
|
{
|
|
readonly StateMachineInitializer expr;
|
|
|
|
public StateMachineMethod (StateMachine host, StateMachineInitializer expr, FullNamedExpression returnType,
|
|
Modifiers mod, MemberName name, ToplevelBlock.Flags blockFlags)
|
|
: base (host, returnType, mod | Modifiers.COMPILER_GENERATED,
|
|
name, ParametersCompiled.EmptyReadOnlyParameters, null)
|
|
{
|
|
this.expr = expr;
|
|
Block = new ToplevelBlock (host.Compiler, ParametersCompiled.EmptyReadOnlyParameters, Location.Null, blockFlags);
|
|
}
|
|
|
|
public override EmitContext CreateEmitContext (ILGenerator ig, SourceMethodBuilder sourceMethod)
|
|
{
|
|
EmitContext ec = new EmitContext (this, ig, MemberType, sourceMethod);
|
|
ec.CurrentAnonymousMethod = expr;
|
|
|
|
if (expr is AsyncInitializer)
|
|
ec.With (BuilderContext.Options.AsyncBody, true);
|
|
|
|
return ec;
|
|
}
|
|
}
|
|
|
|
public abstract class StateMachineInitializer : AnonymousExpression
|
|
{
|
|
sealed class MoveNextBodyStatement : Statement
|
|
{
|
|
readonly StateMachineInitializer state_machine;
|
|
|
|
public MoveNextBodyStatement (StateMachineInitializer stateMachine)
|
|
{
|
|
this.state_machine = stateMachine;
|
|
this.loc = stateMachine.Location;
|
|
}
|
|
|
|
protected override void CloneTo (CloneContext clonectx, Statement target)
|
|
{
|
|
throw new NotSupportedException ();
|
|
}
|
|
|
|
public override bool Resolve (BlockContext ec)
|
|
{
|
|
return true;
|
|
}
|
|
|
|
protected override void DoEmit (EmitContext ec)
|
|
{
|
|
state_machine.EmitMoveNext (ec);
|
|
}
|
|
|
|
public override void Emit (EmitContext ec)
|
|
{
|
|
// Don't create sequence point
|
|
DoEmit (ec);
|
|
}
|
|
|
|
protected override bool DoFlowAnalysis (FlowAnalysisContext fc)
|
|
{
|
|
return state_machine.ReturnType.Kind != MemberKind.Void;
|
|
}
|
|
|
|
public override Reachability MarkReachable (Reachability rc)
|
|
{
|
|
base.MarkReachable (rc);
|
|
|
|
if (state_machine.ReturnType.Kind != MemberKind.Void)
|
|
rc = Reachability.CreateUnreachable ();
|
|
|
|
return rc;
|
|
}
|
|
}
|
|
|
|
public readonly TypeDefinition Host;
|
|
protected StateMachine storey;
|
|
|
|
//
|
|
// The state as we generate the machine
|
|
//
|
|
protected Label move_next_ok;
|
|
protected Label move_next_error;
|
|
LocalBuilder skip_finally;
|
|
protected LocalBuilder current_pc;
|
|
protected List<ResumableStatement> resume_points;
|
|
|
|
protected StateMachineInitializer (ParametersBlock block, TypeDefinition host, TypeSpec returnType)
|
|
: base (block, returnType, block.StartLocation)
|
|
{
|
|
this.Host = host;
|
|
}
|
|
|
|
#region Properties
|
|
|
|
public Label BodyEnd { get; set; }
|
|
|
|
public LocalBuilder CurrentPC
|
|
{
|
|
get {
|
|
return current_pc;
|
|
}
|
|
}
|
|
|
|
public LocalBuilder SkipFinally {
|
|
get {
|
|
return skip_finally;
|
|
}
|
|
}
|
|
|
|
public override AnonymousMethodStorey Storey {
|
|
get {
|
|
return storey;
|
|
}
|
|
}
|
|
|
|
#endregion
|
|
|
|
public int AddResumePoint (ResumableStatement stmt)
|
|
{
|
|
if (resume_points == null)
|
|
resume_points = new List<ResumableStatement> ();
|
|
|
|
resume_points.Add (stmt);
|
|
return resume_points.Count;
|
|
}
|
|
|
|
public override Expression CreateExpressionTree (ResolveContext ec)
|
|
{
|
|
throw new NotSupportedException ("ET");
|
|
}
|
|
|
|
protected virtual BlockContext CreateBlockContext (BlockContext bc)
|
|
{
|
|
var ctx = new BlockContext (bc, block, bc.ReturnType);
|
|
ctx.CurrentAnonymousMethod = this;
|
|
|
|
ctx.AssignmentInfoOffset = bc.AssignmentInfoOffset;
|
|
ctx.EnclosingLoop = bc.EnclosingLoop;
|
|
ctx.EnclosingLoopOrSwitch = bc.EnclosingLoopOrSwitch;
|
|
ctx.Switch = bc.Switch;
|
|
|
|
return ctx;
|
|
}
|
|
|
|
protected override Expression DoResolve (ResolveContext rc)
|
|
{
|
|
var bc = (BlockContext) rc;
|
|
var ctx = CreateBlockContext (bc);
|
|
|
|
Block.Resolve (ctx);
|
|
|
|
if (!rc.IsInProbingMode) {
|
|
var move_next = new StateMachineMethod (storey, this, new TypeExpression (ReturnType, loc), Modifiers.PUBLIC, new MemberName ("MoveNext", loc), 0);
|
|
move_next.Block.AddStatement (new MoveNextBodyStatement (this));
|
|
storey.AddEntryMethod (move_next);
|
|
}
|
|
|
|
bc.AssignmentInfoOffset = ctx.AssignmentInfoOffset;
|
|
eclass = ExprClass.Value;
|
|
return this;
|
|
}
|
|
|
|
public override void Emit (EmitContext ec)
|
|
{
|
|
//
|
|
// Load state machine instance
|
|
//
|
|
storey.Instance.Emit (ec);
|
|
}
|
|
|
|
void EmitMoveNext_NoResumePoints (EmitContext ec)
|
|
{
|
|
ec.EmitThis ();
|
|
ec.Emit (OpCodes.Ldfld, storey.PC.Spec);
|
|
|
|
ec.EmitThis ();
|
|
ec.EmitInt ((int) IteratorStorey.State.After);
|
|
ec.Emit (OpCodes.Stfld, storey.PC.Spec);
|
|
|
|
// We only care if the PC is zero (start executing) or non-zero (don't do anything)
|
|
ec.Emit (OpCodes.Brtrue, move_next_error);
|
|
|
|
BodyEnd = ec.DefineLabel ();
|
|
|
|
var async_init = this as AsyncInitializer;
|
|
if (async_init != null)
|
|
ec.BeginExceptionBlock ();
|
|
|
|
block.EmitEmbedded (ec);
|
|
|
|
if (async_init != null)
|
|
async_init.EmitCatchBlock (ec);
|
|
|
|
ec.MarkLabel (BodyEnd);
|
|
|
|
EmitMoveNextEpilogue (ec);
|
|
|
|
ec.MarkLabel (move_next_error);
|
|
|
|
if (ReturnType.Kind != MemberKind.Void) {
|
|
ec.EmitInt (0);
|
|
ec.Emit (OpCodes.Ret);
|
|
}
|
|
|
|
ec.MarkLabel (move_next_ok);
|
|
}
|
|
|
|
void EmitMoveNext (EmitContext ec)
|
|
{
|
|
move_next_ok = ec.DefineLabel ();
|
|
move_next_error = ec.DefineLabel ();
|
|
|
|
if (resume_points == null) {
|
|
EmitMoveNext_NoResumePoints (ec);
|
|
return;
|
|
}
|
|
|
|
current_pc = ec.GetTemporaryLocal (ec.BuiltinTypes.UInt);
|
|
ec.EmitThis ();
|
|
ec.Emit (OpCodes.Ldfld, storey.PC.Spec);
|
|
ec.Emit (OpCodes.Stloc, current_pc);
|
|
|
|
// We're actually in state 'running', but this is as good a PC value as any if there's an abnormal exit
|
|
ec.EmitThis ();
|
|
ec.EmitInt ((int) IteratorStorey.State.After);
|
|
ec.Emit (OpCodes.Stfld, storey.PC.Spec);
|
|
|
|
Label[] labels = new Label[1 + resume_points.Count];
|
|
labels[0] = ec.DefineLabel ();
|
|
|
|
bool need_skip_finally = false;
|
|
for (int i = 0; i < resume_points.Count; ++i) {
|
|
ResumableStatement s = resume_points[i];
|
|
need_skip_finally |= s is ExceptionStatement;
|
|
labels[i + 1] = s.PrepareForEmit (ec);
|
|
}
|
|
|
|
if (need_skip_finally) {
|
|
skip_finally = ec.GetTemporaryLocal (ec.BuiltinTypes.Bool);
|
|
ec.EmitInt (0);
|
|
ec.Emit (OpCodes.Stloc, skip_finally);
|
|
}
|
|
|
|
var async_init = this as AsyncInitializer;
|
|
if (async_init != null)
|
|
ec.BeginExceptionBlock ();
|
|
|
|
ec.Emit (OpCodes.Ldloc, current_pc);
|
|
ec.Emit (OpCodes.Switch, labels);
|
|
|
|
ec.Emit (async_init != null ? OpCodes.Leave : OpCodes.Br, move_next_error);
|
|
|
|
ec.MarkLabel (labels[0]);
|
|
|
|
BodyEnd = ec.DefineLabel ();
|
|
|
|
block.EmitEmbedded (ec);
|
|
|
|
ec.MarkLabel (BodyEnd);
|
|
|
|
if (async_init != null) {
|
|
async_init.EmitCatchBlock (ec);
|
|
}
|
|
|
|
ec.Mark (Block.Original.EndLocation);
|
|
ec.EmitThis ();
|
|
ec.EmitInt ((int) IteratorStorey.State.After);
|
|
ec.Emit (OpCodes.Stfld, storey.PC.Spec);
|
|
|
|
EmitMoveNextEpilogue (ec);
|
|
|
|
ec.MarkLabel (move_next_error);
|
|
|
|
if (ReturnType.Kind != MemberKind.Void) {
|
|
ec.EmitInt (0);
|
|
ec.Emit (OpCodes.Ret);
|
|
}
|
|
|
|
ec.MarkLabel (move_next_ok);
|
|
|
|
if (ReturnType.Kind != MemberKind.Void) {
|
|
ec.EmitInt (1);
|
|
ec.Emit (OpCodes.Ret);
|
|
}
|
|
}
|
|
|
|
protected virtual void EmitMoveNextEpilogue (EmitContext ec)
|
|
{
|
|
}
|
|
|
|
public void EmitLeave (EmitContext ec, bool unwind_protect)
|
|
{
|
|
// Return ok
|
|
ec.Emit (unwind_protect ? OpCodes.Leave : OpCodes.Br, move_next_ok);
|
|
}
|
|
|
|
//
|
|
// Called back from YieldStatement
|
|
//
|
|
public virtual void InjectYield (EmitContext ec, Expression expr, int resume_pc, bool unwind_protect, Label resume_point)
|
|
{
|
|
//
|
|
// Guard against being disposed meantime
|
|
//
|
|
Label disposed = ec.DefineLabel ();
|
|
var iterator = storey as IteratorStorey;
|
|
if (iterator != null) {
|
|
ec.EmitThis ();
|
|
ec.Emit (OpCodes.Ldfld, iterator.DisposingField.Spec);
|
|
ec.Emit (OpCodes.Brtrue_S, disposed);
|
|
}
|
|
|
|
//
|
|
// store resume program-counter
|
|
//
|
|
ec.EmitThis ();
|
|
ec.EmitInt (resume_pc);
|
|
ec.Emit (OpCodes.Stfld, storey.PC.Spec);
|
|
|
|
if (iterator != null) {
|
|
ec.MarkLabel (disposed);
|
|
}
|
|
|
|
// mark finally blocks as disabled
|
|
if (unwind_protect && skip_finally != null) {
|
|
ec.EmitInt (1);
|
|
ec.Emit (OpCodes.Stloc, skip_finally);
|
|
}
|
|
}
|
|
|
|
public void SetStateMachine (StateMachine stateMachine)
|
|
{
|
|
this.storey = stateMachine;
|
|
}
|
|
}
|
|
|
|
//
|
|
// Iterators are implemented as state machine blocks
|
|
//
|
|
public class Iterator : StateMachineInitializer
|
|
{
|
|
sealed class TryFinallyBlockProxyStatement : Statement
|
|
{
|
|
TryFinallyBlock block;
|
|
Iterator iterator;
|
|
|
|
public TryFinallyBlockProxyStatement (Iterator iterator, TryFinallyBlock block)
|
|
{
|
|
this.iterator = iterator;
|
|
this.block = block;
|
|
}
|
|
|
|
protected override void CloneTo (CloneContext clonectx, Statement target)
|
|
{
|
|
throw new NotSupportedException ();
|
|
}
|
|
|
|
protected override bool DoFlowAnalysis (FlowAnalysisContext fc)
|
|
{
|
|
throw new NotSupportedException ();
|
|
}
|
|
|
|
protected override void DoEmit (EmitContext ec)
|
|
{
|
|
//
|
|
// Restore redirection for any captured variables
|
|
//
|
|
ec.CurrentAnonymousMethod = iterator;
|
|
|
|
using (ec.With (BuilderContext.Options.OmitDebugInfo, !ec.HasMethodSymbolBuilder)) {
|
|
block.EmitFinallyBody (ec);
|
|
}
|
|
}
|
|
}
|
|
|
|
public readonly IMethodData OriginalMethod;
|
|
public readonly bool IsEnumerable;
|
|
public readonly TypeSpec OriginalIteratorType;
|
|
int finally_hosts_counter;
|
|
|
|
public Iterator (ParametersBlock block, IMethodData method, TypeDefinition host, TypeSpec iterator_type, bool is_enumerable)
|
|
: base (block, host, host.Compiler.BuiltinTypes.Bool)
|
|
{
|
|
this.OriginalMethod = method;
|
|
this.OriginalIteratorType = iterator_type;
|
|
this.IsEnumerable = is_enumerable;
|
|
this.type = method.ReturnType;
|
|
}
|
|
|
|
#region Properties
|
|
|
|
public ToplevelBlock Container {
|
|
get { return OriginalMethod.Block; }
|
|
}
|
|
|
|
public override string ContainerType {
|
|
get { return "iterator"; }
|
|
}
|
|
|
|
public override bool IsIterator {
|
|
get { return true; }
|
|
}
|
|
|
|
#endregion
|
|
|
|
public Method CreateFinallyHost (TryFinallyBlock block)
|
|
{
|
|
var method = new Method (storey, new TypeExpression (storey.Compiler.BuiltinTypes.Void, loc),
|
|
Modifiers.COMPILER_GENERATED, new MemberName (CompilerGeneratedContainer.MakeName (null, null, "Finally", finally_hosts_counter++), loc),
|
|
ParametersCompiled.EmptyReadOnlyParameters, null);
|
|
|
|
method.Block = new ToplevelBlock (method.Compiler, method.ParameterInfo, loc,
|
|
ToplevelBlock.Flags.CompilerGenerated | ToplevelBlock.Flags.NoFlowAnalysis);
|
|
|
|
method.Block.AddStatement (new TryFinallyBlockProxyStatement (this, block));
|
|
|
|
// Cannot it add to storey because it'd be emitted before nested
|
|
// anonoymous methods which could capture shared variable
|
|
|
|
return method;
|
|
}
|
|
|
|
public void EmitYieldBreak (EmitContext ec, bool unwind_protect)
|
|
{
|
|
ec.Emit (unwind_protect ? OpCodes.Leave : OpCodes.Br, move_next_error);
|
|
}
|
|
|
|
public override string GetSignatureForError ()
|
|
{
|
|
return OriginalMethod.GetSignatureForError ();
|
|
}
|
|
|
|
public override void Emit (EmitContext ec)
|
|
{
|
|
//
|
|
// Load Iterator storey instance
|
|
//
|
|
storey.Instance.Emit (ec);
|
|
|
|
//
|
|
// Initialize iterator PC when it's unitialized
|
|
//
|
|
if (IsEnumerable) {
|
|
ec.Emit (OpCodes.Dup);
|
|
ec.EmitInt ((int)IteratorStorey.State.Uninitialized);
|
|
|
|
var field = storey.PC.Spec;
|
|
if (storey.MemberName.IsGeneric) {
|
|
field = MemberCache.GetMember (Storey.Instance.Type, field);
|
|
}
|
|
|
|
ec.Emit (OpCodes.Stfld, field);
|
|
}
|
|
}
|
|
|
|
public void EmitDispose (EmitContext ec)
|
|
{
|
|
if (resume_points == null)
|
|
return;
|
|
|
|
Label end = ec.DefineLabel ();
|
|
|
|
Label[] labels = null;
|
|
for (int i = 0; i < resume_points.Count; ++i) {
|
|
ResumableStatement s = resume_points[i];
|
|
Label ret = s.PrepareForDispose (ec, end);
|
|
if (ret.Equals (end) && labels == null)
|
|
continue;
|
|
if (labels == null) {
|
|
labels = new Label[resume_points.Count + 1];
|
|
for (int j = 0; j <= i; ++j)
|
|
labels[j] = end;
|
|
}
|
|
|
|
labels[i + 1] = ret;
|
|
}
|
|
|
|
if (labels != null) {
|
|
current_pc = ec.GetTemporaryLocal (ec.BuiltinTypes.UInt);
|
|
ec.EmitThis ();
|
|
ec.Emit (OpCodes.Ldfld, storey.PC.Spec);
|
|
ec.Emit (OpCodes.Stloc, current_pc);
|
|
}
|
|
|
|
ec.EmitThis ();
|
|
ec.EmitInt (1);
|
|
ec.Emit (OpCodes.Stfld, ((IteratorStorey) storey).DisposingField.Spec);
|
|
|
|
ec.EmitThis ();
|
|
ec.EmitInt ((int) IteratorStorey.State.After);
|
|
ec.Emit (OpCodes.Stfld, storey.PC.Spec);
|
|
|
|
if (labels != null) {
|
|
//SymbolWriter.StartIteratorDispatcher (ec.ig);
|
|
ec.Emit (OpCodes.Ldloc, current_pc);
|
|
ec.Emit (OpCodes.Switch, labels);
|
|
//SymbolWriter.EndIteratorDispatcher (ec.ig);
|
|
|
|
foreach (ResumableStatement s in resume_points)
|
|
s.EmitForDispose (ec, current_pc, end, true);
|
|
}
|
|
|
|
ec.MarkLabel (end);
|
|
}
|
|
|
|
public override void EmitStatement (EmitContext ec)
|
|
{
|
|
throw new NotImplementedException ();
|
|
}
|
|
|
|
public override void InjectYield (EmitContext ec, Expression expr, int resume_pc, bool unwind_protect, Label resume_point)
|
|
{
|
|
// Store the new value into current
|
|
var fe = new FieldExpr (((IteratorStorey) storey).CurrentField, loc);
|
|
fe.InstanceExpression = new CompilerGeneratedThis (storey.CurrentType, loc);
|
|
fe.EmitAssign (ec, expr, false, false);
|
|
|
|
base.InjectYield (ec, expr, resume_pc, unwind_protect, resume_point);
|
|
|
|
EmitLeave (ec, unwind_protect);
|
|
|
|
ec.MarkLabel (resume_point);
|
|
}
|
|
|
|
public static void CreateIterator (IMethodData method, TypeDefinition parent, Modifiers modifiers)
|
|
{
|
|
bool is_enumerable;
|
|
TypeSpec iterator_type;
|
|
|
|
TypeSpec ret = method.ReturnType;
|
|
if (ret == null)
|
|
return;
|
|
|
|
if (!CheckType (ret, parent, out iterator_type, out is_enumerable)) {
|
|
parent.Compiler.Report.Error (1624, method.Location,
|
|
"The body of `{0}' cannot be an iterator block " +
|
|
"because `{1}' is not an iterator interface type",
|
|
method.GetSignatureForError (),
|
|
ret.GetSignatureForError ());
|
|
return;
|
|
}
|
|
|
|
ParametersCompiled parameters = method.ParameterInfo;
|
|
for (int i = 0; i < parameters.Count; i++) {
|
|
Parameter p = parameters [i];
|
|
Parameter.Modifier mod = p.ModFlags;
|
|
if ((mod & Parameter.Modifier.RefOutMask) != 0) {
|
|
parent.Compiler.Report.Error (1623, p.Location,
|
|
"Iterators cannot have ref or out parameters");
|
|
return;
|
|
}
|
|
|
|
if (p is ArglistParameter) {
|
|
parent.Compiler.Report.Error (1636, method.Location,
|
|
"__arglist is not allowed in parameter list of iterators");
|
|
return;
|
|
}
|
|
|
|
if (parameters.Types [i].IsPointer) {
|
|
parent.Compiler.Report.Error (1637, p.Location,
|
|
"Iterators cannot have unsafe parameters or yield types");
|
|
return;
|
|
}
|
|
}
|
|
|
|
if ((modifiers & Modifiers.UNSAFE) != 0) {
|
|
Expression.UnsafeInsideIteratorError (parent.Compiler.Report, method.Location);
|
|
}
|
|
|
|
method.Block = method.Block.ConvertToIterator (method, parent, iterator_type, is_enumerable);
|
|
}
|
|
|
|
static bool CheckType (TypeSpec ret, TypeContainer parent, out TypeSpec original_iterator_type, out bool is_enumerable)
|
|
{
|
|
original_iterator_type = null;
|
|
is_enumerable = false;
|
|
|
|
if (ret.BuiltinType == BuiltinTypeSpec.Type.IEnumerable) {
|
|
original_iterator_type = parent.Compiler.BuiltinTypes.Object;
|
|
is_enumerable = true;
|
|
return true;
|
|
}
|
|
if (ret.BuiltinType == BuiltinTypeSpec.Type.IEnumerator) {
|
|
original_iterator_type = parent.Compiler.BuiltinTypes.Object;
|
|
is_enumerable = false;
|
|
return true;
|
|
}
|
|
|
|
InflatedTypeSpec inflated = ret as InflatedTypeSpec;
|
|
if (inflated == null)
|
|
return false;
|
|
|
|
var member_definition = inflated.MemberDefinition;
|
|
PredefinedType ptype = parent.Module.PredefinedTypes.IEnumerableGeneric;
|
|
|
|
if (ptype.Define () && ptype.TypeSpec.MemberDefinition == member_definition) {
|
|
original_iterator_type = inflated.TypeArguments[0];
|
|
is_enumerable = true;
|
|
return true;
|
|
}
|
|
|
|
ptype = parent.Module.PredefinedTypes.IEnumeratorGeneric;
|
|
if (ptype.Define () && ptype.TypeSpec.MemberDefinition == member_definition) {
|
|
original_iterator_type = inflated.TypeArguments[0];
|
|
is_enumerable = false;
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
}
|
|
}
|
|
|