The following conditional identities are applied:
c ? x : x -> x
false ? x : y -> y; true ? x : y -> x
c ? true : false -> c; c ? false : true -> !c
!c ? x : y -> c ? y : x
Lastly, for expression chains x, y in a conditional expression
c ? x : y,
we evaluate all conditionals in the expression chains with the
condition c, assuming c is true (for x), or false (for y).
The following unary identities are applied:
||x|| -> |x|
|-x| -> |x|
~(~x) -> x
f(g(x)) -> g(x), where f(), g() are floor() or ceil() functions.
-(-x) -> x
!!x -> x
!(x == y) -> x != y, !(x < y) -> x >= y, etc (for integers).
We largely ignore the target type when preprocessing, but still
dereference options.target_type in a couple of places. E.g. when setting
info.target_type. We could add more checks for options.preprocess_only
to account for that, but it seems more robust to make sure
options.target_type is never NULL.
Since commit eaebef4265 we may receive
vsir generated from HLSL sources, which typically contains SSA values.
We could previously receive vsir with SSA values as well, but HLSL
sources would go through d3dbc/tpf as an intermediate step, making the
resulting vsir much less likely to contain SSA values.
