Beispiel #1
0
        internal override void GenerateMethodBody(TypeCompilationState compilationState, DiagnosticBag diagnostics)
        {
            ImmutableArray <LocalSymbol> declaredLocalsArray;
            var body        = _generateMethodBody(this, diagnostics, out declaredLocalsArray, out _lazyResultProperties);
            var compilation = compilationState.Compilation;

            _lazyReturnType = CalculateReturnType(compilation, body);

            // Can't do this until the return type has been computed.
            TypeParameterChecker.Check(this, _allTypeParameters);

            if (diagnostics.HasAnyErrors())
            {
                return;
            }

            DiagnosticsPass.IssueDiagnostics(compilation, body, diagnostics, this);
            if (diagnostics.HasAnyErrors())
            {
                return;
            }

            // Check for use-site diagnostics (e.g. missing types in the signature).
            DiagnosticInfo useSiteDiagnosticInfo = null;

            this.CalculateUseSiteDiagnostic(ref useSiteDiagnosticInfo);
            if (useSiteDiagnosticInfo != null && useSiteDiagnosticInfo.Severity == DiagnosticSeverity.Error)
            {
                diagnostics.Add(useSiteDiagnosticInfo, this.Locations[0]);
                return;
            }

            try
            {
                var declaredLocals = PooledHashSet <LocalSymbol> .GetInstance();

                try
                {
                    // Rewrite local declaration statement.
                    body = (BoundStatement)LocalDeclarationRewriter.Rewrite(
                        compilation,
                        _container,
                        declaredLocals,
                        body,
                        declaredLocalsArray,
                        diagnostics);

                    // Verify local declaration names.
                    foreach (var local in declaredLocals)
                    {
                        Debug.Assert(local.Locations.Length > 0);
                        var name = local.Name;
                        if (name.StartsWith("$", StringComparison.Ordinal))
                        {
                            diagnostics.Add(ErrorCode.ERR_UnexpectedCharacter, local.Locations[0], name[0]);
                            return;
                        }
                    }

                    // Rewrite references to placeholder "locals".
                    body = (BoundStatement)PlaceholderLocalRewriter.Rewrite(compilation, _container, declaredLocals, body, diagnostics);

                    if (diagnostics.HasAnyErrors())
                    {
                        return;
                    }
                }
                finally
                {
                    declaredLocals.Free();
                }

                var syntax            = body.Syntax;
                var statementsBuilder = ArrayBuilder <BoundStatement> .GetInstance();

                statementsBuilder.Add(body);
                // Insert an implicit return statement if necessary.
                if (body.Kind != BoundKind.ReturnStatement)
                {
                    statementsBuilder.Add(new BoundReturnStatement(syntax, RefKind.None, expressionOpt: null));
                }

                var localsSet = PooledHashSet <LocalSymbol> .GetInstance();

                try
                {
                    var localsBuilder = ArrayBuilder <LocalSymbol> .GetInstance();

                    foreach (var local in this.LocalsForBinding)
                    {
                        Debug.Assert(!localsSet.Contains(local));
                        localsBuilder.Add(local);
                        localsSet.Add(local);
                    }
                    foreach (var local in this.Locals)
                    {
                        if (localsSet.Add(local))
                        {
                            localsBuilder.Add(local);
                        }
                    }

                    body = new BoundBlock(syntax, localsBuilder.ToImmutableAndFree(), statementsBuilder.ToImmutableAndFree())
                    {
                        WasCompilerGenerated = true
                    };

                    Debug.Assert(!diagnostics.HasAnyErrors());
                    Debug.Assert(!body.HasErrors);

                    bool sawLambdas;
                    bool sawLocalFunctions;
                    bool sawAwaitInExceptionHandler;
                    ImmutableArray <SourceSpan> dynamicAnalysisSpans = ImmutableArray <SourceSpan> .Empty;
                    body = LocalRewriter.Rewrite(
                        compilation: this.DeclaringCompilation,
                        method: this,
                        methodOrdinal: _methodOrdinal,
                        containingType: _container,
                        statement: body,
                        compilationState: compilationState,
                        previousSubmissionFields: null,
                        allowOmissionOfConditionalCalls: false,
                        instrumentForDynamicAnalysis: false,
                        debugDocumentProvider: null,
                        dynamicAnalysisSpans: ref dynamicAnalysisSpans,
                        diagnostics: diagnostics,
                        sawLambdas: out sawLambdas,
                        sawLocalFunctions: out sawLocalFunctions,
                        sawAwaitInExceptionHandler: out sawAwaitInExceptionHandler,
                        conceptWitnessesToHoist: out var conceptWitnessesToHoist /* @MattWindsor91 (Concept-C# 2017) */);

                    Debug.Assert(!sawAwaitInExceptionHandler);
                    Debug.Assert(dynamicAnalysisSpans.Length == 0);

                    if (body.HasErrors)
                    {
                        return;
                    }

                    // @MattWindsor91 (Concept-C# 2017)
                    //
                    // Inject witness dictionary construction here, because the
                    // correct place for it is not yet obvious.
                    //
                    // Copied from MethodCompiler, might not work.  Mainly here
                    // to plug the gap til we can do this right.
                    //
                    // TODO: handle this properly.
                    if (conceptWitnessesToHoist != null)
                    {
                        body = MethodCompiler.HoistConceptWitnesses(conceptWitnessesToHoist, body);
                    }

                    // Variables may have been captured by lambdas in the original method
                    // or in the expression, and we need to preserve the existing values of
                    // those variables in the expression. This requires rewriting the variables
                    // in the expression based on the closure classes from both the original
                    // method and the expression, and generating a preamble that copies
                    // values into the expression closure classes.
                    //
                    // Consider the original method:
                    // static void M()
                    // {
                    //     int x, y, z;
                    //     ...
                    //     F(() => x + y);
                    // }
                    // and the expression in the EE: "F(() => x + z)".
                    //
                    // The expression is first rewritten using the closure class and local <1>
                    // from the original method: F(() => <1>.x + z)
                    // Then lambda rewriting introduces a new closure class that includes
                    // the locals <1> and z, and a corresponding local <2>: F(() => <2>.<1>.x + <2>.z)
                    // And a preamble is added to initialize the fields of <2>:
                    //     <2> = new <>c__DisplayClass0();
                    //     <2>.<1> = <1>;
                    //     <2>.z = z;

                    // Rewrite "this" and "base" references to parameter in this method.
                    // Rewrite variables within body to reference existing display classes.
                    body = (BoundStatement)CapturedVariableRewriter.Rewrite(
                        this.GenerateThisReference,
                        compilation.Conversions,
                        _displayClassVariables,
                        body,
                        diagnostics);

                    if (body.HasErrors)
                    {
                        Debug.Assert(false, "Please add a test case capturing whatever caused this assert.");
                        return;
                    }

                    if (diagnostics.HasAnyErrors())
                    {
                        return;
                    }

                    if (sawLambdas || sawLocalFunctions)
                    {
                        var closureDebugInfoBuilder = ArrayBuilder <ClosureDebugInfo> .GetInstance();

                        var lambdaDebugInfoBuilder = ArrayBuilder <LambdaDebugInfo> .GetInstance();

                        body = LambdaRewriter.Rewrite(
                            loweredBody: body,
                            thisType: this.SubstitutedSourceMethod.ContainingType,
                            thisParameter: _thisParameter,
                            method: this,
                            methodOrdinal: _methodOrdinal,
                            substitutedSourceMethod: this.SubstitutedSourceMethod.OriginalDefinition,
                            closureDebugInfoBuilder: closureDebugInfoBuilder,
                            lambdaDebugInfoBuilder: lambdaDebugInfoBuilder,
                            slotAllocatorOpt: null,
                            compilationState: compilationState,
                            diagnostics: diagnostics,
                            assignLocals: localsSet);

                        // we don't need this information:
                        closureDebugInfoBuilder.Free();
                        lambdaDebugInfoBuilder.Free();
                    }
                }
                finally
                {
                    localsSet.Free();
                }

                // Insert locals from the original method,
                // followed by any new locals.
                var block        = (BoundBlock)body;
                var localBuilder = ArrayBuilder <LocalSymbol> .GetInstance();

                foreach (var local in this.Locals)
                {
                    Debug.Assert(!(local is EELocalSymbol) || (((EELocalSymbol)local).Ordinal == localBuilder.Count));
                    localBuilder.Add(local);
                }
                foreach (var local in block.Locals)
                {
                    if (local is EELocalSymbol oldLocal)
                    {
                        Debug.Assert(localBuilder[oldLocal.Ordinal] == oldLocal);
                        continue;
                    }
                    localBuilder.Add(local);
                }

                body = block.Update(localBuilder.ToImmutableAndFree(), block.LocalFunctions, block.Statements);
                TypeParameterChecker.Check(body, _allTypeParameters);
                compilationState.AddSynthesizedMethod(this, body);
            }
            catch (BoundTreeVisitor.CancelledByStackGuardException ex)
            {
                ex.AddAnError(diagnostics);
            }
        }