/// <summary>
/// Try to get a field with given reference in this type.
/// The declaring type of the method reference is assumed to refer to this type.
/// </summary>
public bool TryGet(XFieldReference fieldRef, out XFieldDefinition field)
{
// Look in my own fields
field = Fields.FirstOrDefault(x => x.IsSameExceptDeclaringType(fieldRef));
if (field != null)
{
return(true);
}
// Look in base type
XTypeDefinition baseTypeDef;
if ((BaseType != null) && BaseType.TryResolve(out baseTypeDef))
{
return(baseTypeDef.TryGet(fieldRef, out field));
}
return(false);
}
/// <summary>
/// Try to get a field with given reference in this type.
/// The declaring type of the method reference is assumed to refer to this type.
/// </summary>
public bool TryGet(XFieldReference fieldRef, out XFieldDefinition field)
{
// Look in my own fields
field = Fields.FirstOrDefault(x => x.IsSameExceptDeclaringType(fieldRef));
if (field != null)
return true;
// Look in base type
XTypeDefinition baseTypeDef;
if ((BaseType != null) && BaseType.TryResolve(out baseTypeDef))
{
return baseTypeDef.TryGet(fieldRef, out field);
}
return false;
}
private static bool InterlockedUsingUpdater(AstExpression interlockedCall, string methodName, XFieldReference field,
XFieldDefinition updater, AstExpression targetExpr, AstExpression parentExpr,
AssemblyCompiler compiler)
{
bool isStatic = field.Resolve().IsStatic;
string replacementMethod = null;
if (methodName == "Increment")
replacementMethod = "IncrementAndGet";
else if (methodName == "Decrement")
replacementMethod = "DecrementAndGet";
else if (methodName == "Add")
replacementMethod = "AddAndGet";
else if (methodName == "Read")
replacementMethod = "Get";
else if (methodName.StartsWith("Exchange"))
replacementMethod = "GetAndSet";
else if (methodName.StartsWith("CompareAndSet"))
// this patches through to the original java method for performance purists.
replacementMethod = "CompareAndSet";
else if (methodName.StartsWith("CompareExchange"))
{
if (TransformCompareExchangeToCompareAndSet(parentExpr, compiler, ref interlockedCall))
replacementMethod = "CompareAndSet";
else
{
// The semantics here are slighlty different. Java returns a 'true' on
// success, while BCL returns the old value. We have crafted a replacement
// method with the BCL semantics though.
replacementMethod = "CompareExchange";
}
}
else
{
return false;
}
var updaterType = updater.FieldType.Resolve();
var methodRef = updaterType.Methods.FirstOrDefault(f => f.Name == replacementMethod);
if (methodRef == null && methodName=="CompareExchange")
methodRef = updaterType.Methods.FirstOrDefault(f => f.Name.StartsWith(replacementMethod));
if (methodRef == null)
return false;
interlockedCall.Operand = methodRef;
if (isStatic)
interlockedCall.Arguments[0] = new AstExpression(interlockedCall.SourceLocation, AstCode.Ldnull, null)
.SetType(field.DeclaringType);
else
interlockedCall.Arguments[0] = targetExpr.Arguments[0];
// add field updater instance argument.
var ldUpdater = new AstExpression(interlockedCall.SourceLocation, AstCode.Ldsfld, updater)
.SetType(updaterType);
interlockedCall.Arguments.Insert(0, ldUpdater);
return true;
}
public static XTypeReference GetFieldType(XFieldReference fieldReference)
{
return SubstituteTypeArgs(UnpackModifiers(fieldReference.FieldType), fieldReference);
}
private static void FailsafeInterlockedUsingLocking(XFieldReference field, AstExpression expr,
AstExpression targetExpr, AstBlock block, int idx,
AssemblyCompiler compiler, MethodSource currentMethod)
{
if (currentMethod.IsDotNet && !currentMethod.ILMethod.DeclaringType.HasSuppressMessageAttribute("InterlockedFallback"))
{
bool isStatic = field != null && field.Resolve().IsStatic;
DLog.Warning(DContext.CompilerCodeGenerator,
"Emulating Interlocked call using failsafe locking mechanism in {0}{1}. Consider using AtomicXXX classes instead. You can suppress this message with an [SuppressMessage(\"dot42\", \"InterlockedFallback\")] attribute on the class.",
currentMethod.Method.FullName, !isStatic ? "" : " because a static field is referenced");
}
// replace with:
// Monitor.Enter();
// try { <original expression> } finally { Monitor.Exit(); }
//
// note that the lock is larger than it has to be, since it also sourrounds
// the parameter evaluation.
// It must sourround the storing and loading of the reference parameters though.
var typeSystem = compiler.Module.TypeSystem;
var monitorType = compiler.GetDot42InternalType("System.Threading", "Monitor");
var enterMethod = monitorType.Resolve().Methods.Single(p => p.Name == "Enter");
var exitMethod = monitorType.Resolve().Methods.Single(p => p.Name == "Exit");
AstExpression loadLockTarget = null;
if (field != null)
{
if (field.Resolve().IsStatic)
{
// lock on the field's class typedef.
// but always the element type, not on a generic instance (until Dot42 implements proper generic static field handling)
loadLockTarget = new AstExpression(expr.SourceLocation, AstCode.LdClass, field.DeclaringType.GetElementType())
.SetType(typeSystem.Type);
}
else
{
// lock on the fields object
loadLockTarget = targetExpr.Arguments[0];
}
}
if (loadLockTarget == null)
{
// something went wrong. use a global lock.
DLog.Warning(DContext.CompilerCodeGenerator, "unable to infer target of Interlocked call. using global lock.");
var interlockedType = compiler.GetDot42InternalType("System.Threading", "Interlocked");
loadLockTarget = new AstExpression(expr.SourceLocation, AstCode.LdClass, interlockedType)
.SetType(typeSystem.Type);
}
var lockVar = new AstGeneratedVariable("lockTarget$", "") {Type = typeSystem.Object};
var storeLockVar = new AstExpression(expr.SourceLocation, AstCode.Stloc, lockVar, loadLockTarget);
var loadLockVar = new AstExpression(expr.SourceLocation, AstCode.Ldloc, lockVar);
var enterCall = new AstExpression(expr.SourceLocation, AstCode.Call, enterMethod, storeLockVar);
var replacementBlock = new AstBlock(expr.SourceLocation);
replacementBlock.Body.Add(enterCall);
var tryCatch = new AstTryCatchBlock(expr.SourceLocation)
{
TryBlock = new AstBlock(expr.SourceLocation, expr),
FinallyBlock = new AstBlock(expr.SourceLocation,
new AstExpression(block.SourceLocation, AstCode.Call, exitMethod, loadLockVar))
};
replacementBlock.Body.Add(tryCatch);
if (block.EntryGoto == expr)
block.EntryGoto = enterCall;
block.Body[idx] = replacementBlock;
}
/// <summary>
/// Is this reference equal to the given other reference?
/// </summary>
public virtual bool IsSameExceptDeclaringType(XFieldReference other)
{
return (Name == other.Name) && FieldType.IsSame(other.FieldType);
}
/// <summary>
/// Is this reference equal to the given other reference?
/// </summary>
public bool IsSame(XFieldReference other)
{
return DeclaringType.IsSame(other.DeclaringType) && IsSameExceptDeclaringType(other);
}
/// <summary>
/// Is this reference equal to the given other reference?
/// </summary>
public virtual bool IsSameExceptDeclaringType(XFieldReference other)
{
return((Name == other.Name) && FieldType.IsSame(other.FieldType));
}
/// <summary>
/// Is this reference equal to the given other reference?
/// </summary>
public bool IsSame(XFieldReference other)
{
return(DeclaringType.IsSame(other.DeclaringType) && IsSameExceptDeclaringType(other));
}
