Similarly to the modulus operator, d3dbc results with constant folding
are different from results when constant folding cannot be applied, and
different from tpf results.
Note that in d3dbc target profiles it gives different results when this
operation is constant folded compared to when it is not.
This suggests that whatever pass lowers the modulus operation to d3dbc
operations doesn't do it before constant folding.
Also note that when constant folded, d3dbc results differ from tpf
results for negative operands, because of the loss of precision that
happens when NEG is constant folded.
So the same integer modulus expression can have 3 different results
depending on the context.
This test is currently miscompiling on SM4 because
copy_propagation_invalidate_variable_from_deref_recurse() is not always
invalidating the right components.
Basically, separate lower_casts_to_int() into the lowering of the CAST
and the lowering of the TRUNC, so that TRUNCs that are not part of a
cast are lowered as well.
While fxc allows full expressions inside the angle brackets, we don't parse that
yet as it'd be quite a mess to properly do so with yacc, and I'm not aware of any
game doing so in their shaders.
