internal List <CodeInstruction> FinalizeILCodes(Emitter emitter, List <MethodInfo> transpilers, List <Label> endLabels, out bool hasReturnCode)
{
hasReturnCode = false;
if (generator == null)
{
return(null);
}
// pass1 - define labels and add them to instructions that are target of a jump
//
foreach (var ilInstruction in ilInstructions)
{
switch (ilInstruction.opcode.OperandType)
{
case OperandType.InlineSwitch:
{
var targets = ilInstruction.operand as ILInstruction[];
if (targets != null)
{
var labels = new List <Label>();
foreach (var target in targets)
{
var label = generator.DefineLabel();
target.labels.Add(label);
labels.Add(label);
}
ilInstruction.argument = labels.ToArray();
}
break;
}
case OperandType.ShortInlineBrTarget:
case OperandType.InlineBrTarget:
{
var target = ilInstruction.operand as ILInstruction;
if (target != null)
{
var label = generator.DefineLabel();
target.labels.Add(label);
ilInstruction.argument = label;
}
break;
}
}
}
// pass2 - filter through all processors
//
var codeTranspiler = new CodeTranspiler(ilInstructions, argumentShift);
transpilers.Do(transpiler => codeTranspiler.Add(transpiler));
var codeInstructions = codeTranspiler.GetResult(generator, method);
if (emitter == null)
{
return(codeInstructions);
}
emitter.LogComment("start original");
// pass3 - log out all new local variables
//
var savedLog = FileLog.GetBuffer(true);
emitter.LogAllLocalVariables();
FileLog.LogBuffered(savedLog);
// pass4 - check for any RET
//
hasReturnCode = codeInstructions.Any(code => code.opcode == OpCodes.Ret);
// pass5 - remove RET if it appears at the end
//
while (true)
{
var lastInstruction = codeInstructions.LastOrDefault();
if (lastInstruction == null || lastInstruction.opcode != OpCodes.Ret)
{
break;
}
// remember any existing labels
endLabels.AddRange(lastInstruction.labels);
codeInstructions.RemoveAt(codeInstructions.Count - 1);
}
// pass6 - mark labels and exceptions and emit codes
//
codeInstructions.Do(codeInstruction =>
{
// mark all labels
codeInstruction.labels.Do(label => emitter.MarkLabel(label));
// start all exception blocks
// TODO: we ignore the resulting label because we have no way to use it
//
codeInstruction.blocks.Do(block =>
{
emitter.MarkBlockBefore(block, out var label);
});
var code = codeInstruction.opcode;
var operand = codeInstruction.operand;
// replace RET with a jump to the end (outside this code)
if (code == OpCodes.Ret)
{
var endLabel = generator.DefineLabel();
code = OpCodes.Br;
operand = endLabel;
endLabels.Add(endLabel);
}
// replace short jumps with long ones (can be optimized but requires byte counting, not instruction counting)
if (shortJumps.TryGetValue(code, out var longJump))
{
code = longJump;
}
switch (code.OperandType)
{
case OperandType.InlineNone:
emitter.Emit(code);
break;
case OperandType.InlineSig:
var cecilGenerator = generator.GetProxiedShim <CecilILGenerator>();
if (cecilGenerator == null)
{
// Right now InlineSignatures can only be emitted using MonoMod.Common and its CecilILGenerator.
// That is because DynamicMethod's original ILGenerator is very restrictive about the calli opcode.
throw new NotSupportedException();
}
if (operand == null)
{
throw new Exception($"Wrong null argument: {codeInstruction}");
}
if ((operand is ICallSiteGenerator) == false)
{
throw new Exception($"Wrong Emit argument type {operand.GetType()} in {codeInstruction}");
}
emitter.AddInstruction(code, operand);
emitter.LogIL(code, operand);
cecilGenerator.Emit(code, (ICallSiteGenerator)operand);
break;
default:
if (operand == null)
{
throw new Exception($"Wrong null argument: {codeInstruction}");
}
emitter.AddInstruction(code, operand);
emitter.LogIL(code, operand);
_ = generator.DynEmit(code, operand);
break;
}
codeInstruction.blocks.Do(block => emitter.MarkBlockAfter(block));
});
emitter.LogComment("end original");
return(codeInstructions);
}