[Mesa-dev] [PATCH] tgsi: document and fixup IF and BREAKC instrunctions

[Zack Rusin]

> ----- Original Message -----
> > ----- Original Message -----
> > > Ah.. This indeed rings a bell. I don't recall the details but I'm pretty
> > > sure
> > > I was against dual semantics. And the fact that this problem is again
> > > showing its ugly head is the proof of it.
> > > 
> > > We really should have two IF opcodes. And the state tracker should choose
> > > which one it wants.
> > 
> > What would be the difference between those two opcodes though?
> 
> > The current IF
> > does a bitwise comparison,
> 
> No, according to Marek, the current IF code has two possible behaviors:
> - a float comparison for drivers which do not support native integers (i915)
> - a bit comparison for drivers which support native integers (others)
> 
> This would be the different for both opcodes. We could call the former FIF or
> just IF, and the later UIF.

Yes, I understand what you're arguing for, I don't understand how you want to get there with those two opcodes. Do you want to change the current tgsi exec behavior of IF and introduce a new UIF opcode or do you want to introduce a new FIF opcode that does the float comparisons? Also, which one does the current glsl compiler depend on?