private void EmitOpCode()
{
if (_currBlock == null)
{
return;
}
int opcIndex = _opcIndex;
if (opcIndex == 0)
{
MarkLabel(GetLabel(_currBlock.Position));
}
bool isLastOp = opcIndex == CurrBlock.OpCodes.Count - 1;
if (isLastOp && CurrBlock.Branch != null &&
(ulong)CurrBlock.Branch.Position <= (ulong)CurrBlock.Position)
{
EmitSynchronization();
}
//On AARCH32 mode, (almost) all instruction can be conditionally
//executed, and the required condition is encoded on the opcode.
//We handle that here, skipping the instruction if the condition
//is not met. We can just ignore it when the condition is "Always",
//because in this case the instruction is always going to be executed.
//Condition "Never" is also ignored because this is a special encoding
//used by some unconditional instructions.
ILLabel lblSkip = null;
if (CurrOp is OpCode32 op && op.Cond < Condition.Al)
{
lblSkip = new ILLabel();
EmitCondBranch(lblSkip, GetInverseCond(op.Cond));
}
CurrOp.Emitter(this);
if (lblSkip != null)
{
MarkLabel(lblSkip);
//If this is the last op on the block, and there's no "next" block
//after this one, then we have to return right now, with the address
//of the next instruction to be executed (in the case that the condition
//is false, and the branch was not taken, as all basic blocks should end with
//some kind of branch).
if (isLastOp && CurrBlock.Next == null)
{
EmitStoreState();
EmitLdc_I8(CurrOp.Position + CurrOp.OpCodeSizeInBytes);
Emit(OpCodes.Ret);
}
}
_ilBlock.Add(new ILBarrier());
}
public void EmitRor(int amount)
{
if (amount > 0)
{
Stloc(RorTmpIndex, VarType.Int);
Ldloc(RorTmpIndex, VarType.Int);
EmitLdc_I4(amount);
Emit(OpCodes.Shr_Un);
Ldloc(RorTmpIndex, VarType.Int);
EmitLdc_I4(CurrOp.GetBitsCount() - amount);
Emit(OpCodes.Shl);
Emit(OpCodes.Or);
}
}
