copy_propagation_compute_replacement() is not doing very much for us, and
conceptually is a bit of an odd fit anyway, since it's meant to deal with
multi-component types.
Note that in the future we should call
validate_static_object_references() after DCE and pruning branches,
because shaders such as these compile (at least in more modern versions
of the native compiler):
Branch pruning:
```
static RWTexture2D<float> tex;
float4 main() : sv_target
{
if (0)
{
tex[int2(0, 0)] = 2;
}
return 0;
}
```
DCE:
```
static Texture2D tex;
uniform uint i;
float4 main() : sv_target
{
float4 unused = tex.Load(int3(0, 1, 2));
return 0;
}
```
These are "todo" tests in hlsl-static-initializer.shader_test
that depend on this.
Otherwise, for instance, the added test results in:
debug_hlsl_writemask: Assertion `!(writemask & ~VKD3DSP_WRITEMASK_ALL)' failed.
Which happens in allocate_variable_temp_register() when the variable's
type reg_size is <= 4 but its component count is larger, which may
happen if it contains objects.
This should silence warnings about some branches non returning any value
without requiring additional "return 0" statement or similar.
Also, in theory this might enable to compiler to optimize the program
a little bit more, though that's unlikely to have any measurable effect.
It is responsibility of the shader's programmer to ensure that
object references can be solved statically.
Resource arrays for ps_5_1 and vs_5_1 are an exception which is not
properly handled yet. They probably deserve a different object type.
Signed-off-by: Francisco Casas <fcasas@codeweavers.com>
