Vertex shaders do not have CMP, so we use SLT and MAD.
For example, this vertex shader:
uniform float4 f;
void main(inout float4 pos : position, out float4 t1 : TEXCOORD1)
{
t1 = (int4)f;
}
results in:
vs_2_0
dcl_position v0
slt r0, c0, -c0
frc r1, c0
add r2, -r1, c0
slt r1, -r1, r1
mad oT1, r0, r1, r2
mov oPos, v0
while we have the lower_cmp() pass, each time it is applied many
instructions are generated, so this patch introduces a specialized
version of the cast-to-int lowering for efficiency.
Otherwise ubsan reports runtime errors such as:
libs/vkd3d-shader/ir.c:4731:5: runtime error: null pointer passed as argument 1, which is declared to never be null
Since we have -Wswitch, this forces the developer to update all relevant
switches when an enum case is added.
Places where the default is just a FIXME are left alone.
The previous names "not normalised" and "fully normalised" have meanings
which are likely to change with time. OTOH including a description of the
normalisation level in the enumerant seems excessive. Relating
normalisation levels to shader model versions might be a reasonable
compromise.
