/// <summary>
/// Update the variables used in the given node (and all children) using the given mapping function.
/// </summary>
private static void ReplaceVariables(AstNode node, Func <AstVariable, AstVariable> variableMapping)
{
var expr = node as AstExpression;
if (expr != null)
{
var v = expr.Operand as AstVariable;
if (v != null)
{
expr.Operand = variableMapping(v);
}
expr.Arguments.ForEach(x => ReplaceVariables(x, variableMapping));
}
else
{
var catchBlock = node as AstTryCatchBlock.CatchBlock;
if ((catchBlock != null) && (catchBlock.ExceptionVariable != null))
{
catchBlock.ExceptionVariable = variableMapping(catchBlock.ExceptionVariable);
}
foreach (var child in node.GetChildren())
{
ReplaceVariables(child, variableMapping);
}
}
}
void AnalyzeNode(AstNode node)
{
AstExpression expr = node as AstExpression;
if (expr != null) {
AstVariable locVar = expr.Operand as AstVariable;
if (locVar != null) {
if (expr.Code == AstCode.Stloc) {
numStloc[locVar] = numStloc.GetOrDefault(locVar) + 1;
} else if (expr.Code == AstCode.Ldloc) {
numLdloc[locVar] = numLdloc.GetOrDefault(locVar) + 1;
} else if (expr.Code == AstCode.Ldloca) {
numLdloca[locVar] = numLdloca.GetOrDefault(locVar) + 1;
} else {
throw new NotSupportedException(expr.Code.ToString());
}
}
foreach (AstExpression child in expr.Arguments)
AnalyzeNode(child);
} else {
var catchBlock = node as AstTryCatchBlock.CatchBlock;
if (catchBlock != null && catchBlock.ExceptionVariable != null) {
numStloc[catchBlock.ExceptionVariable] = numStloc.GetOrDefault(catchBlock.ExceptionVariable) + 1;
}
foreach (AstNode child in node.GetChildren())
AnalyzeNode(child);
}
}
private void VisitChilden(AstNode node)
{
foreach (var child in node.GetChildren())
{
child.Accept(this);
}
}
/// <summary>
/// Creates the "ExpressionToInfer" instances (=nodes in dependency graph)
/// </summary>
/// <remarks>
/// We are using a dependency graph to ensure that expressions are analyzed in the correct order.
/// </remarks>
private void CreateDependencyGraph(AstNode node)
{
var catchBlock = node as AstTryCatchBlock.CatchBlock;
if (catchBlock != null && catchBlock.ExceptionVariable != null && catchBlock.ExceptionType != null && catchBlock.ExceptionVariable.Type == null)
{
catchBlock.ExceptionVariable.Type = catchBlock.ExceptionType;
}
var expr = node as AstExpression;
if (expr != null)
{
var expressionToInfer = new ExpressionToInfer(expr);
allExpressions.Add(expressionToInfer);
FindNestedAssignments(expr, expressionToInfer);
if ((expr.Code == AstCode.Stloc) && ((AstVariable) expr.Operand).Type == null)
{
assignmentExpressions[(AstVariable)expr.Operand].Add(expressionToInfer);
}
return;
}
foreach (var child in node.GetChildren())
{
CreateDependencyGraph(child);
}
}
/// <summary>
/// Flattens all nested basic blocks, except the the top level 'node' argument
/// </summary>
private static void FlattenBasicBlocks(AstNode node)
{
var block = node as AstBlock;
if (block != null)
{
var flatBody = new List <AstNode>();
foreach (var child in block.GetChildren())
{
FlattenBasicBlocks(child);
var childAsBB = child as AstBasicBlock;
if (childAsBB != null)
{
if (!(childAsBB.Body.FirstOrDefault() is AstLabel))
{
throw new Exception("Basic block has to start with a label. \n" + childAsBB);
}
if (childAsBB.Body.LastOrDefault() is AstExpression &&
!childAsBB.Body.LastOrDefault().IsUnconditionalControlFlow())
{
// I got this error when using mapsforge, in createBitmap()
// https://raw.githubusercontent.com/mapsforge/mapsforge/master/mapsforge-map/src/main/java/org/mapsforge/map/rendertheme/XmlUtils.java
// Apparently it is related to the finally statement.
// I have no idea what it means to disable this check.
//throw new Exception("Basic block has to end with unconditional control flow. \n" + childAsBB);
}
flatBody.AddRange(childAsBB.GetChildren());
}
else
{
flatBody.Add(child);
}
}
block.EntryGoto = null;
block.Body = flatBody;
}
else if (node is AstExpression)
{
// Optimization - no need to check expressions
}
else if (node != null)
{
// Recursively find all ILBlocks
foreach (var child in node.GetChildren())
{
FlattenBasicBlocks(child);
}
}
}
void AnalyzeNode(AstNode node)
{
AstExpression expr = node as AstExpression;
if (expr != null)
{
AstVariable locVar = expr.Operand as AstVariable;
if (locVar != null)
{
if (expr.Code == AstCode.Stloc)
{
numStloc[locVar] = numStloc.GetOrDefault(locVar) + 1;
}
else if (expr.Code == AstCode.Ldloc)
{
numLdloc[locVar] = numLdloc.GetOrDefault(locVar) + 1;
}
else if (expr.Code == AstCode.Ldloca)
{
numLdloca[locVar] = numLdloca.GetOrDefault(locVar) + 1;
}
else
{
throw new NotSupportedException(expr.Code.ToString());
}
}
foreach (AstExpression child in expr.Arguments)
{
AnalyzeNode(child);
}
}
else
{
var catchBlock = node as AstTryCatchBlock.CatchBlock;
if (catchBlock != null && catchBlock.ExceptionVariable != null)
{
numStloc[catchBlock.ExceptionVariable] = numStloc.GetOrDefault(catchBlock.ExceptionVariable) + 1;
}
foreach (AstNode child in node.GetChildren())
{
AnalyzeNode(child);
}
}
}
/// <summary>
/// Flattens all nested basic blocks, except the the top level 'node' argument
/// </summary>
private static void FlattenBasicBlocks(AstNode node)
{
var block = node as AstBlock;
if (block != null)
{
var flatBody = new List <AstNode>();
foreach (var child in block.GetChildren())
{
FlattenBasicBlocks(child);
var childAsBB = child as AstBasicBlock;
if (childAsBB != null)
{
if (!(childAsBB.Body.FirstOrDefault() is AstLabel))
{
throw new Exception("Basic block has to start with a label. \n" + childAsBB);
}
if (childAsBB.Body.LastOrDefault() is AstExpression && !childAsBB.Body.LastOrDefault().IsUnconditionalControlFlow())
{
throw new Exception("Basic block has to end with unconditional control flow. \n" + childAsBB);
}
flatBody.AddRange(childAsBB.GetChildren());
}
else
{
flatBody.Add(child);
}
}
block.EntryGoto = null;
block.Body = flatBody;
}
else if (node is AstExpression)
{
// Optimization - no need to check expressions
}
else if (node != null)
{
// Recursively find all ILBlocks
foreach (var child in node.GetChildren())
{
FlattenBasicBlocks(child);
}
}
}