protected internal override void VisitLdLoc(LdLoc inst)
{
if (inst.Variable == thisVariable)
{
inst.ReplaceWith(target.Clone());
return;
}
base.VisitLdLoc(inst);
}
static void DoPropagate(ILVariable v, ILInstruction copiedExpr, Block block, ref int i, ILTransformContext context)
{
context.Step($"Copy propagate {v.Name}", copiedExpr);
// un-inline the arguments of the ldArg instruction
ILVariable[] uninlinedArgs = new ILVariable[copiedExpr.Children.Count];
for (int j = 0; j < uninlinedArgs.Length; j++)
{
var arg = copiedExpr.Children[j];
var type = context.TypeSystem.Compilation.FindType(arg.ResultType.ToKnownTypeCode());
uninlinedArgs[j] = new ILVariable(VariableKind.StackSlot, type, arg.ResultType, arg.ILRange.Start)
{
Name = "C_" + arg.ILRange.Start
};
block.Instructions.Insert(i++, new StLoc(uninlinedArgs[j], arg));
}
CollectionExtensions.AddRange(v.Function.Variables, uninlinedArgs);
// perform copy propagation:
foreach (var expr in v.LoadInstructions.ToArray())
{
var clone = copiedExpr.Clone();
for (int j = 0; j < uninlinedArgs.Length; j++)
{
clone.Children[j].ReplaceWith(new LdLoc(uninlinedArgs[j]));
}
expr.ReplaceWith(clone);
}
block.Instructions.RemoveAt(i);
int c = ILInlining.InlineInto(block, i, aggressive: false, context: context);
i -= c + 1;
}
public ILInstruction Instr()
{
if (Instruction is null)
{
return(null);
}
if (InstructionWasGivenOut)
{
return(Instruction.Clone());
}
else
{
InstructionWasGivenOut = true;
return(Instruction);
}
}