private static bool ValueMatches(int value, int comparisonValue, RequirementOperator comparisonType)
{
switch (comparisonType)
{
case RequirementOperator.None:
return(true);
case RequirementOperator.Equal:
return(value == comparisonValue);
case RequirementOperator.NotEqual:
return(value != comparisonValue);
case RequirementOperator.LessThan:
return(value < comparisonValue);
case RequirementOperator.LessThanOrEqual:
return(value <= comparisonValue);
case RequirementOperator.GreaterThan:
return(value > comparisonValue);
case RequirementOperator.GreaterThanOrEqual:
return(value >= comparisonValue);
default:
return(false);
}
}
public void TestToString(RequirementType requirementType, TestField left, RequirementOperator requirementOperator, TestField right, int hitCount, string expected)
{
var requirement = new Requirement
{
Type = requirementType,
Left = GetField(left),
Operator = requirementOperator,
Right = GetField(right),
HitCount = (uint)hitCount
};
Assert.That(requirement.ToString(), Is.EqualTo(expected));
}
/// <summary>
/// Gets the logically opposing operator.
/// </summary>
public static RequirementOperator GetOpposingOperator(RequirementOperator op)
{
switch (op)
{
case RequirementOperator.Equal: return(RequirementOperator.NotEqual);
case RequirementOperator.NotEqual: return(RequirementOperator.Equal);
case RequirementOperator.LessThan: return(RequirementOperator.GreaterThanOrEqual);
case RequirementOperator.LessThanOrEqual: return(RequirementOperator.GreaterThan);
case RequirementOperator.GreaterThan: return(RequirementOperator.LessThanOrEqual);
case RequirementOperator.GreaterThanOrEqual: return(RequirementOperator.LessThan);
default: return(RequirementOperator.None);
}
}
private static RequirementOperator GetReversedRequirementOperator(RequirementOperator op)
{
switch (op)
{
case RequirementOperator.Equal: return(RequirementOperator.Equal);
case RequirementOperator.NotEqual: return(RequirementOperator.NotEqual);
case RequirementOperator.LessThan: return(RequirementOperator.GreaterThan);
case RequirementOperator.LessThanOrEqual: return(RequirementOperator.GreaterThanOrEqual);
case RequirementOperator.GreaterThan: return(RequirementOperator.LessThan);
case RequirementOperator.GreaterThanOrEqual: return(RequirementOperator.LessThanOrEqual);
default: return(RequirementOperator.None);
}
}
private static ParseErrorExpression HandleAddAddressComparison(ExpressionBase comparison,
IList <Requirement> requirements, RequirementOperator op, Requirement extraRequirement)
{
// determine how long the AddAddress chain is
var rightIndex = requirements.Count;
while (requirements[rightIndex - 1].Type == RequirementType.AddAddress)
{
rightIndex--;
}
// attempt to match the AddAddress chain with the previous conditions
bool match = true;
var distance = requirements.Count - rightIndex;
var leftIndex = rightIndex - 1;
var leftStop = leftIndex - distance;
var requirement = requirements[leftIndex]; // last element of left side
while (leftIndex > leftStop)
{
// if the AddAddress portion doesn't match, skip over any remaining AddAddresses
// for the previous condition, and bail
if (requirements[leftIndex - 1] != requirements[leftIndex + distance])
{
while (leftIndex > 0 && requirements[leftIndex - 1].Type == RequirementType.AddAddress)
{
--leftIndex;
}
match = false;
break;
}
--leftIndex;
}
// if the AddAddress chains match, then merge the conditions
if (match)
{
while (requirements.Count > rightIndex)
{
requirements.RemoveAt(requirements.Count - 1);
}
requirement.Operator = op;
requirement.Right = extraRequirement.Left;
return(null);
}
// put the extra requirement back. we couldn't merge it with the left condition
requirements.Add(extraRequirement);
// AddAddress chains were not the same. Attempt to rearrange the logic using SubSource
// (if A cannot be moved) (if A can be moved)
// A == B ~> A - B + 0 == 0 ~> B - A == 0 ~> -A + B == 0
// A != B ~> A - B + 0 != 0 ~> B - A != 0 ~> -A + B != 0
// A > B ~> A - B + M > M ~> B - A < 0 ~> -A + B > M [leverage underflow]
// A >= B ~> A - B + M >= M ~> B - A <= 0 ~> -A - 1 + B >= M [leverage underflow]
// A < B ~> A - B + 0 > M ~> B - A + M > M ~> -A + B + M > M [avoid underflow]
// A <= B ~> A - B + 0 >= M ~> B - A + M >= M ~> -A + B + M >= M [avoid underflow]
// calculate M
uint maxValue = 0;
if (op != RequirementOperator.Equal && op != RequirementOperator.NotEqual)
{
maxValue = Math.Max(Field.GetMaxValue(requirement.Left.Size), Field.GetMaxValue(extraRequirement.Left.Size));
if (maxValue == 0xFFFFFFFF)
{
return(new ParseErrorExpression("Indirect memory addresses must match on both sides of a comparison for 32-bit values", comparison));
}
}
// if A is preceded by an AddSource or SubSource, we can't change it to a SubSource
Requirement prevReq = null;
bool cannotBeChanged = false;
if (leftIndex > 0)
{
prevReq = requirements[leftIndex - 1];
cannotBeChanged =
(prevReq.Type == RequirementType.AddSource || prevReq.Type == RequirementType.SubSource);
}
if (cannotBeChanged)
{
requirement.Type = RequirementType.AddSource;
extraRequirement.Type = RequirementType.SubSource;
uint leftValue = 0;
switch (op)
{
case RequirementOperator.GreaterThan:
case RequirementOperator.GreaterThanOrEqual:
leftValue = maxValue;
break;
case RequirementOperator.LessThan:
op = RequirementOperator.GreaterThan;
break;
case RequirementOperator.LessThanOrEqual:
op = RequirementOperator.GreaterThanOrEqual;
break;
}
// if preceeded by a constant, merge the constant into the final condition
if (prevReq.Left.Type == FieldType.Value)
{
if (prevReq.Type == RequirementType.AddSource)
{
leftValue += prevReq.Left.Value;
}
else if (prevReq.Left.Value < leftValue)
{
leftValue -= prevReq.Left.Value;
}
else
{
maxValue += prevReq.Left.Value;
}
requirements.RemoveAt(leftIndex - 1);
}
extraRequirement = new Requirement();
extraRequirement.Left = new Field {
Type = FieldType.Value, Value = leftValue
};
extraRequirement.Operator = op;
extraRequirement.Right = new Field {
Type = FieldType.Value, Value = maxValue
};
requirements.Add(extraRequirement);
return(null);
}
// if A can be changed, make it a SubSource
requirement.Type = RequirementType.SubSource;
switch (op)
{
case RequirementOperator.GreaterThanOrEqual: // -A - 1 + B >= M
// subtract 1 from (B-A) in case B==A, so the result will still be negative
requirements.Insert(rightIndex, new Requirement
{
Type = RequirementType.SubSource,
Left = new Field {
Type = FieldType.Value, Value = 1
}
});
goto case RequirementOperator.GreaterThan;
case RequirementOperator.Equal: // -A + B == 0
case RequirementOperator.NotEqual: // -A + B != 0
case RequirementOperator.GreaterThan: // -A + B > M
extraRequirement.Operator = op;
extraRequirement.Right = new Field {
Type = FieldType.Value, Value = maxValue
};
break;
case RequirementOperator.LessThan: // -A + B + M > M
case RequirementOperator.LessThanOrEqual: // -A + B + M >= M
extraRequirement.Type = RequirementType.AddSource;
extraRequirement = new Requirement();
extraRequirement.Left = extraRequirement.Right =
new Field {
Type = FieldType.Value, Value = maxValue
};
extraRequirement.Operator = (op == RequirementOperator.LessThan) ?
RequirementOperator.GreaterThan : RequirementOperator.GreaterThanOrEqual;
requirements.Add(extraRequirement);
break;
}
return(null);
}
public void TestAppendStringHex(RequirementType requirementType, TestField left, RequirementOperator requirementOperator, TestField right, int hitCount, string expected)
{
var requirement = new Requirement
{
Type = requirementType,
Left = GetField(left),
Operator = requirementOperator,
Right = GetField(right),
HitCount = (uint)hitCount
};
var builder = new StringBuilder();
requirement.AppendString(builder, NumberFormat.Hexadecimal);
Assert.That(builder.ToString(), Is.EqualTo(expected));
}
public bool Parse(out int number, out RequirementOperator comparison)
{
string expression = Text;
int index = 0;
if (String.IsNullOrEmpty(expression))
{
number = 0;
comparison = RequirementOperator.None;
return(true);
}
switch (expression[0])
{
case '<':
++index;
if (expression[index] == '=')
{
++index;
comparison = RequirementOperator.LessThanOrEqual;
}
else
{
comparison = RequirementOperator.LessThan;
}
break;
case '>':
++index;
if (expression[index] == '=')
{
++index;
comparison = RequirementOperator.GreaterThanOrEqual;
}
else
{
comparison = RequirementOperator.GreaterThan;
}
break;
case '!':
++index;
if (expression[index] == '=')
{
++index;
}
comparison = RequirementOperator.NotEqual;
break;
case '=':
++index;
if (expression[index] == '=')
{
++index;
}
comparison = RequirementOperator.Equal;
break;
default:
comparison = RequirementOperator.Equal;
break;
}
if (index > 0)
{
expression = expression.Substring(index);
}
return(Int32.TryParse(expression, out number));
}
protected ParseErrorExpression BuildTrigger(TriggerBuilderContext context, InterpreterScope scope, FunctionCallExpression functionCall, ExpressionBase address)
{
var requirement = new Requirement();
var integerConstant = address as IntegerConstantExpression;
if (integerConstant != null)
{
requirement.Left = new Field {
Size = this.Size, Type = FieldType.MemoryAddress, Value = (uint)integerConstant.Value
};
context.Trigger.Add(requirement);
return(null);
}
IntegerConstantExpression offsetConstant = null;
IntegerConstantExpression scalarConstant = null;
RequirementOperator scalarOperation = RequirementOperator.None;
var originalAddress = address;
var funcCall = address as FunctionCallExpression;
if (funcCall == null)
{
var mathematic = address as MathematicExpression;
if (mathematic != null &&
(mathematic.Operation == MathematicOperation.Add || mathematic.Operation == MathematicOperation.Subtract))
{
if (CountMathematicMemoryAccessors(mathematic, 2) >= 2)
{
return(new ParseErrorExpression("Cannot construct single address lookup from multiple memory references", address));
}
offsetConstant = mathematic.Right as IntegerConstantExpression;
if (offsetConstant != null)
{
address = mathematic.Left;
}
else
{
offsetConstant = mathematic.Left as IntegerConstantExpression;
if (offsetConstant != null)
{
address = mathematic.Right;
}
}
if (offsetConstant != null)
{
if (mathematic.Operation == MathematicOperation.Subtract)
{
offsetConstant = new IntegerConstantExpression(-offsetConstant.Value);
}
}
mathematic = address as MathematicExpression;
}
if (mathematic != null)
{
switch (mathematic.Operation)
{
case MathematicOperation.Multiply:
scalarConstant = mathematic.Right as IntegerConstantExpression;
if (scalarConstant != null)
{
address = mathematic.Left;
scalarOperation = RequirementOperator.Multiply;
}
else
{
scalarConstant = mathematic.Left as IntegerConstantExpression;
if (scalarConstant != null)
{
scalarOperation = RequirementOperator.Multiply;
address = mathematic.Right;
}
}
break;
case MathematicOperation.Divide:
scalarConstant = mathematic.Right as IntegerConstantExpression;
if (scalarConstant != null)
{
address = mathematic.Left;
scalarOperation = RequirementOperator.Divide;
}
break;
case MathematicOperation.BitwiseAnd:
scalarConstant = mathematic.Right as IntegerConstantExpression;
if (scalarConstant != null)
{
address = mathematic.Left;
scalarOperation = RequirementOperator.BitwiseAnd;
}
break;
}
}
funcCall = address as FunctionCallExpression;
}
if (funcCall != null)
{
var funcDef = scope.GetFunction(funcCall.FunctionName.Name) as TriggerBuilderContext.FunctionDefinition;
if (funcDef != null)
{
if (funcDef is MemoryAccessorFunction || funcDef is PrevPriorFunction)
{
var error = funcDef.BuildTrigger(context, scope, funcCall);
if (error != null)
{
return(error);
}
var lastRequirement = context.LastRequirement;
lastRequirement.Type = RequirementType.AddAddress;
if (scalarConstant != null && scalarConstant.Value != 1)
{
lastRequirement.Operator = scalarOperation;
lastRequirement.Right = new Field {
Size = FieldSize.DWord, Type = FieldType.Value, Value = (uint)scalarConstant.Value
};
}
// a memory reference without an offset has to be generated with a 0 offset.
uint offset = (offsetConstant != null) ? (uint)offsetConstant.Value : 0;
requirement.Left = new Field {
Size = this.Size, Type = FieldType.MemoryAddress, Value = offset
};
context.Trigger.Add(requirement);
return(null);
}
}
}
var builder = new StringBuilder();
builder.Append("Cannot convert to an address: ");
originalAddress.AppendString(builder);
return(new ParseErrorExpression(builder.ToString(), address));
}