private void RenameVariables()
{
var derived_variables = new Dictionary <IVariable, Stack <DerivedVariable> >();
var indices = new Dictionary <IVariable, uint>();
foreach (var variable in method.Variables)
{
var derived = new DerivedVariable(variable, 0u);
var stack = new Stack <DerivedVariable>();
stack.Push(derived);
derived_variables.Add(variable, stack);
indices.Add(variable, 1u);
}
this.RenameParameters(derived_variables);
this.RenameVariables(cfg.Entry, derived_variables, indices);
}
private void RenameVariables(CFGNode node, IDictionary <IVariable, Stack <DerivedVariable> > derived_variables, Dictionary <IVariable, uint> indices)
{
foreach (var instruction in node.Instructions)
{
DerivedVariable result_derived = null;
if (instruction is DefinitionInstruction)
{
var definition = instruction as DefinitionInstruction;
//if (definition.HasResult && indices.ContainsKey(definition.Result))
if (definition.HasResult)
{
var result = definition.Result;
var index = indices[result];
result_derived = new DerivedVariable(result, index);
definition.Result = result_derived;
}
}
foreach (var variable in instruction.UsedVariables)
{
// When the instruction is a phi, its arguments (used variables)
// are already derived variables, so there is no entry in
// derived_variables dictionary for them.
if (!derived_variables.ContainsKey(variable))
{
continue;
}
var stack = derived_variables[variable];
var derived = stack.Peek();
instruction.Replace(variable, derived);
}
if (result_derived != null)
{
var result = result_derived.Original;
var index = result_derived.Index;
var result_stack = derived_variables[result];
result_stack.Push(result_derived);
indices[result] = index + 1;
}
}
foreach (var succ in node.Successors)
{
if (!phi_instructions.ContainsKey(succ))
{
continue;
}
var node_phi_instructions = phi_instructions[succ];
foreach (var entry in node_phi_instructions)
{
var variable = entry.Key;
var phi = entry.Value;
var stack = derived_variables[variable];
var derived = stack.Peek();
phi.Arguments.Add(derived);
}
}
foreach (var child in node.ImmediateDominated)
{
this.RenameVariables(child, derived_variables, indices);
}
foreach (var instruction in node.Instructions)
{
if (instruction is DefinitionInstruction)
{
var definition = instruction as DefinitionInstruction;
if (definition.HasResult)
{
var derived = definition.Result as DerivedVariable;
var result = derived.Original;
var stack = derived_variables[result];
stack.Pop();
}
}
}
}
