private static void EmitVirtualCallOrJump(ILEmitterCtx context, bool isJump)
{
if (context.Tier == TranslationTier.Tier0)
{
context.Emit(OpCodes.Dup);
context.EmitSttmp();
context.EmitLdarg(TranslatedSub.StateArgIdx);
context.EmitFieldLoad(typeof(CpuThreadState).GetField(nameof(CpuThreadState.CurrentTranslator),
BindingFlags.Instance |
BindingFlags.NonPublic));
context.EmitLdarg(TranslatedSub.StateArgIdx);
context.EmitLdtmp();
context.EmitPrivateCall(typeof(Translator), nameof(Translator.TranslateVirtualSubroutine));
context.Emit(OpCodes.Ret);
}
else
{
context.EmitSttmp();
context.EmitLdarg(TranslatedSub.StateArgIdx);
context.EmitFieldLoad(typeof(CpuThreadState).GetField(nameof(CpuThreadState.CurrentTranslator),
BindingFlags.Instance |
BindingFlags.NonPublic));
context.EmitLdarg(TranslatedSub.StateArgIdx);
context.EmitLdtmp();
context.EmitPrivateCall(typeof(Translator), nameof(Translator.GetOrTranslateVirtualSubroutine));
context.EmitLdarg(TranslatedSub.StateArgIdx);
context.EmitLdarg(TranslatedSub.MemoryArgIdx);
if (isJump)
{
//The tail prefix allows the JIT to jump to the next function,
//while releasing the stack space used by the current one.
//This is ideal for BR ARM instructions, which are
//basically indirect tail calls.
context.Emit(OpCodes.Tailcall);
}
MethodInfo mthdInfo = typeof(ArmSubroutine).GetMethod("Invoke");
context.EmitCall(mthdInfo, isVirtual: true);
if (!isJump)
{
EmitContinueOrReturnCheck(context);
}
else
{
context.Emit(OpCodes.Ret);
}
}
}
public static void EmitCall(ILEmitterCtx context, long imm)
{
if (context.Tier == TranslationTier.Tier0)
{
context.EmitStoreState();
context.TranslateAhead(imm);
context.EmitLdc_I8(imm);
context.Emit(OpCodes.Ret);
return;
}
if (!context.TryOptEmitSubroutineCall())
{
context.HasSlowCall = true;
context.EmitStoreState();
context.TranslateAhead(imm);
context.EmitLdarg(TranslatedSub.StateArgIdx);
context.EmitFieldLoad(typeof(CpuThreadState).GetField(nameof(CpuThreadState.CurrentTranslator),
BindingFlags.Instance |
BindingFlags.NonPublic));
context.EmitLdarg(TranslatedSub.StateArgIdx);
context.EmitLdc_I8(imm);
context.EmitLdc_I4((int)CallType.Call);
context.EmitPrivateCall(typeof(Translator), nameof(Translator.GetOrTranslateSubroutine));
context.EmitLdarg(TranslatedSub.StateArgIdx);
context.EmitLdarg(TranslatedSub.MemoryArgIdx);
context.EmitCall(typeof(TranslatedSub), nameof(TranslatedSub.Execute));
}
EmitContinueOrReturnCheck(context);
}