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using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Microsoft.Cci;
using Microsoft.Cci.MetadataReader;
using Microsoft.Cci.MutableCodeModel;
using Microsoft.Cci.Contracts;
using Microsoft.Cci.ILToCodeModel;
using Bpl = Microsoft.Boogie;
using System.Diagnostics.Contracts;
namespace BytecodeTranslator {
class WholeProgram : TraverserFactory {
/// <summary>
/// Table to be filled by the metadata traverser before visiting any assemblies.
///
/// The table lists the direct supertypes of all type definitions that it encounters during the
/// traversal. (But the table is organized so that subTypes[T] is the list of type definitions
/// that are direct subtypes of T.)
/// </summary>
readonly public Dictionary<ITypeReference, List<ITypeReference>> subTypes = new Dictionary<ITypeReference, List<ITypeReference>>();
public override MetadataTraverser MakeMetadataTraverser(Sink sink,
IDictionary<IUnit, IContractProvider> contractProviders, // TODO: remove this parameter?
IDictionary<IUnit, PdbReader> pdbReaders) {
return new WholeProgramMetadataSemantics(this, sink, pdbReaders);
}
public class WholeProgramMetadataSemantics : MetadataTraverser {
readonly WholeProgram parent;
readonly Sink sink;
readonly Dictionary<IUnit, bool> codeUnderAnalysis = new Dictionary<IUnit, bool>();
public WholeProgramMetadataSemantics(WholeProgram parent, Sink sink, IDictionary<IUnit, PdbReader> pdbReaders)
: base(sink, pdbReaders) {
this.parent = parent;
this.sink = sink;
}
public override void TranslateAssemblies(IEnumerable<IUnit> assemblies) {
#region traverse all of the units gathering type information
var typeRecorder = new RecordSubtypes(this.parent.subTypes);
foreach (var a in assemblies) {
this.codeUnderAnalysis.Add(a, true);
typeRecorder.Visit(a);
}
#endregion
base.TranslateAssemblies(assemblies);
}
class RecordSubtypes : BaseMetadataTraverser {
Dictionary<ITypeReference, List<ITypeReference>> subTypes;
public RecordSubtypes(Dictionary<ITypeReference, List<ITypeReference>> subTypes) {
this.subTypes = subTypes;
}
public override void Visit(ITypeDefinition typeDefinition) {
foreach (var baseClass in typeDefinition.BaseClasses) {
if (!this.subTypes.ContainsKey(baseClass)) {
this.subTypes[baseClass] = new List<ITypeReference>();
}
this.subTypes[baseClass].Add(typeDefinition);
}
base.Visit(typeDefinition);
}
}
}
public override ExpressionTraverser MakeExpressionTraverser(Sink sink, StatementTraverser/*?*/ statementTraverser, bool contractContext) {
return new WholeProgramExpressionSemantics(this, sink, statementTraverser, contractContext);
}
/// <summary>
/// implement virtual method calls to methods defined in the CUA (code under analysis, i.e.,
/// the set of assemblies being translated) by a "switch statement" that dispatches to the
/// most derived type's method. I.e., make explicit the dynamic dispatch mechanism.
/// </summary>
public class WholeProgramExpressionSemantics : CLRSemantics.CLRExpressionSemantics {
readonly WholeProgram parent;
readonly public Dictionary<ITypeReference, List<ITypeReference>> subTypes;
public WholeProgramExpressionSemantics(WholeProgram parent, Sink sink, StatementTraverser/*?*/ statementTraverser, bool contractContext)
: base(sink, statementTraverser, contractContext) {
this.parent = parent;
this.subTypes = parent.subTypes;
}
public override void Visit(IMethodCall methodCall) {
if (!methodCall.IsVirtualCall) {
base.Visit(methodCall);
return;
}
var containingType = methodCall.MethodToCall.ContainingType;
List<ITypeReference> subTypesOfContainingType;
if (!this.subTypes.TryGetValue(containingType, out subTypesOfContainingType)) {
base.Visit(methodCall);
return;
}
Contract.Assert(0 < subTypesOfContainingType.Count);
Contract.Assert(!methodCall.IsStaticCall);
var resolvedMethod = methodCall.MethodToCall.ResolvedMethod;
Contract.Assert(!resolvedMethod.IsConstructor);
var overrides = FindOverrides(containingType, resolvedMethod);
if (0 == overrides.Count) {
base.Visit(methodCall);
return;
}
Bpl.IToken token = methodCall.Token();
List<Bpl.Expr> inexpr;
List<Bpl.IdentifierExpr> outvars;
Bpl.IdentifierExpr thisExpr;
List<Bpl.Variable> locals;
List<IFieldDefinition> args;
Bpl.Expr arrayExpr;
Bpl.Expr indexExpr;
Dictionary<Bpl.IdentifierExpr, Bpl.IdentifierExpr> toBoxed;
var proc = TranslateArgumentsAndReturnProcedure(token, methodCall.MethodToCall, resolvedMethod, methodCall.IsStaticCall ? null : methodCall.ThisArgument, methodCall.Arguments, out inexpr, out outvars, out thisExpr, out locals, out args, out arrayExpr, out indexExpr, out toBoxed);
Bpl.QKeyValue attrib = null;
foreach (var a in resolvedMethod.Attributes) {
if (TypeHelper.GetTypeName(a.Type).EndsWith("AsyncAttribute")) {
attrib = new Bpl.QKeyValue(token, "async", new List<object>(), null);
break;
}
}
var elseBranch = new Bpl.StmtListBuilder();
var methodname = proc.Name;
Bpl.CallCmd call;
if (attrib != null)
call = new Bpl.CallCmd(token, methodname, inexpr, outvars, attrib);
else
call = new Bpl.CallCmd(token, methodname, inexpr, outvars);
elseBranch.Add(call);
Bpl.IfCmd ifcmd = null;
Contract.Assume(1 <= overrides.Count);
foreach (var typeMethodPair in overrides) {
var t = typeMethodPair.Item1;
var m = typeMethodPair.Item2;
var thenBranch = new Bpl.StmtListBuilder();
methodname = TranslationHelper.CreateUniqueMethodName(m); // REVIEW: Shouldn't this be call to FindOrCreateProcedure?
if (attrib != null)
call = new Bpl.CallCmd(token, methodname, inexpr, outvars, attrib);
else
call = new Bpl.CallCmd(token, methodname, inexpr, outvars);
thenBranch.Add(call);
ifcmd = new Bpl.IfCmd(token,
Bpl.Expr.Binary(Bpl.BinaryOperator.Opcode.Eq,
this.sink.Heap.DynamicType(inexpr[0]),
Bpl.Expr.Ident(this.sink.FindOrCreateType(t))
),
thenBranch.Collect(token),
null,
elseBranch.Collect(token)
);
elseBranch = new Bpl.StmtListBuilder();
elseBranch.Add(ifcmd);
}
this.StmtTraverser.StmtBuilder.Add(ifcmd);
return;
}
/// <summary>
/// Modifies <paramref name="overrides"/> as side-effect.
/// </summary>
private List<Tuple<ITypeReference, IMethodReference>> FindOverrides(ITypeReference type, IMethodDefinition resolvedMethod) {
Contract.Requires(type != null);
Contract.Requires(resolvedMethod != null);
var overrides = new List<Tuple<ITypeReference, IMethodReference>>();
foreach (var subType in this.subTypes[type]) {
var overriddenMethod = MemberHelper.GetImplicitlyOverridingDerivedClassMethod(resolvedMethod, subType.ResolvedType);
if (overriddenMethod != Dummy.Method) {
resolvedMethod = overriddenMethod;
}
overrides.Add(Tuple.Create<ITypeReference, IMethodReference>(subType, resolvedMethod));
if (this.subTypes.ContainsKey(subType)) {
overrides.AddRange(FindOverrides(subType, resolvedMethod));
}
}
return overrides;
}
}
}
}
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